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Antioxidant, antiproliferative, and immunostimulatory effects of cell wall α-D-mannan fractions from Kluyveromyces marxianus
Abstract
This study evaluated the antioxidant, antiproliferative, and immunostimulatory properties of cell wall α-D-mannan fractions from yeast Kluyveromyces marxianus CCT7735. Filter centrifugation was used to obtain four fractions (KMM-1, KMM-2, KMM-3, and KMM-4) with molecular weight ranging from 7.6 to 75.1kDa. KMM-1 and KMM-2 comprised D-mannose with traces of D-glucose, whereas other fractions contained only D-mannose. Total sugar found in samples ranged from 85.9% to 96.1%, while protein and phenolic contents were 1.21% and 0.41%, respectively. Although only KMM-1 was able to scavenge superoxide radicals, all fractions presented total antioxidant capacity as well as reducing power, hydroxyl-radical scavenging, and copper- and iron-chelating activities. No fraction was cytotoxic to HeLa cells. However, all samples inhibited the proliferation of the tumor cell Hep-G2 and presented minor cytotoxicity against normal 3T3 cells. All fractions showed mitogenic activity in macrophages and all, except KMM-4, induced nitric oxide production in macrophages, suggestive of their immunostimulatory effects.
... Mannoproteins have good emulsifying properties and can be used as stabilizers in food emulsions, with encouraging results in a wide range of pH conditions. β-Glucans and mannans also have the effect of improving the intestinal environment Wang et al., 2019), stimulating immunity (Lee et al., 2021;Liu et al., 2022;Thomas et al., 2022), absorbing mycotoxins (Aazami et al., 2018;Kim et al., 2019;Luo et al., 2015), promoting wound healing (Grip et al., 2021;Zhou et al., 2023), antioxidant (Galinari et al., 2018;Tang et al., 2017;Zhao et al., 2022), and lowering blood glucose and lipids (Cao et al., 2016;Shituleni et al., 2016). In addition, chemical and physical modifications can improve the antioxidant capacity of yeast polysaccharides Yuan et al., 2022), and chemical and biological modifications can enhance the immunological activity of yeast polysaccharides (Faustino et al., 2021;Khan et al., 2016). ...
... Using 1% NaOH, the yield of mannans was 18%, and mannans have a good scavenging ability for superoxide anion and hydroxyl radical . When extracting polysaccharides, the reaction time is too long, alkaline environment can hydrolyze the mannans into polysaccharides with a smaller molecular weight , and the smaller molecular weight polysaccharides usually perform higher antioxidant activities such as scavenging of superoxide anion and DPPH radicals (Galinari et al., 2018;Zhao et al., 2022). Faustino et al. (2022) also found that the highest yield of yeast mannans (58.82%) was obtained with 0.25 M NaOH and that both 1.5 M and 0.25 M NaOH treatments resulted in the formation of mannans with a low molecular weight, this may be due to the hydrolysis of mannan in an alkaline environment. ...
... Phosphorylated polysaccharide derivatives show better bioactivity, and the addition of phosphate groups increases the production of hydroxyl groups and complexation with metal ions, which affects the antioxidant capacity of polysaccharides (Tang et al., 2017). Yeast mannans with molecular weights ranging from 7.6 to 75.1 kDa, namely, KMM 1-4 (Galinari et al., 2018). The antioxidant capacity of yeast mannans to initiate, replicate, and terminate the oxidation process was evaluated. ...
Yeast cell wall (YCW) polysaccharides, including β‐glucans, mannans, chitins, and glycogens, can be extracted from the waste of beer industry. They are environmentally friendly, abundant, inexpensive raw materials, and have shown broad biological activities and application potentials. The exploitation of yeast polysaccharides is of great importance for environmental protection and resource utilization. This paper reviews the structural features and preparation of YCW polysaccharides. The solubility and emulsification of yeast polysaccharides and the properties of binding metal ions are presented. In addition, biological activities such as blood glucose and lipid lowering, immune regulation, antioxidant, promotion of intestinal health, and promotion of wound healing are proposed, highlighting the beneficial effects of yeast polysaccharides on human health. Through modification, the physical and chemical properties of yeast polysaccharides are changed, which emphasizes the promotion of their biological activities and properties. In addition, the food applications of yeast polysaccharides, including the food packaging film, emulsifier, thickening agent, and fat alternatives, are focused and discussed.
... This yeast can be used to production of enzymes, such as β-galactosidase, β-glucosidase, inulinase, and polygalacturonase (Barnby et al. 1990;Pessoa Jr and Vitolo 1999); single-cell proteins (Schultz et al. 2006); aromatic compounds (Medeiros et al. 2001); and ethanol (Ballesteros et al. 2004;Banat et al. 1996). Other potential applications of the yeast K. marxianus include reduction of lactose content in food products (Martins et al. 2002); production of bioingredients from whey cheese (Belem et al. 1997); bioremediation (Aksu and Dönmez 2000), baker's yeast (Caballero et al. 1995); fatty acids (Bilal et al 2022), anticholesterolemic action (Yoshida et al. 2004); a host for heterologous protein production (Panuwatsuk and Silva 2002;van Ooyen et al. 2006); and antioxidant, antiproliferative, and immunostimulatory activities (Maccaferri et al. 2012;Galinari et al. 2017Galinari et al. , 2018. In addition, studies have shown that K. marxianus modulates the inflammatory process (Stefanova et al. 2010;Romanin et al. 2016). ...
... Galinari et al. (2017) reported mannan (KMM-5) from K. marxianus CCT7735 with Mw 203 kDa. Other mannans were reported (KMM-1, KMM-2, KMM-3, and KMM-4) with molecular weight ranging from 7.6 to 75.1 kDa from K. marxianus CCT7735 (Galinari et al. 2018). Lukondeh et al. (2003 reported polysaccharides from K. marxianus FII 510700 with Mws ranging from 66 to 97 kDa. ...
... The literature already reported the antioxidant, antiproliferative, and immunostimulatory activities of cell wall α-d-mannan from K. marxianus (Galinari et al. 2018). These results show that α-d-mannan from K. marxianus also produces antinociception possibly due to inhibition of inflammation. ...
The management of inflammatory states typically involves non-steroidal anti-inflammatory drugs (NSAIDs) and opiates. Understanding the mechanisms underlying the processing of nociceptive information from potential alternatives such as some polysaccharides may enable new and meaningful therapeutic approaches. In this study, α-d-mannan isolated from the Kluyveromyces marxianus cell wall produced antinociceptive effects in models of inflammatory pain (formalin and complete Freund’s adjuvant tests). Furthermore, α-d-mannan reduced paw edema and interleukin-6 (IL-6) production after carrageenan-induced inflammation. The polysaccharide α-d-mannan was characterized by gas chromatography–mass spectrometry, methylation analysis, and spectroscopic techniques. Moreover, the Doehlert experimental design was applied to find the optimal conditions for biomass production, with the best conditions being 10.8 g/L and 117 h for the glucose concentration and the fermentation time, respectively. These results indicate that α-d-mannan from K. marxianus exerts anti-inflammatory and antinociceptive effects in mice, possibly via a mechanism dependent on the inhibition of IL-6 production.
... The ability of the samples to chelate the iron ion was performed according to Galinari et al. [25] The mixture of 910 mL of each the sample, 30 mL of ferrous chloride (2 mM) and 60 mL of ferrozine (5 mM) was incubated for 10 minutes at 37 C. The absorbance was measured at 562 nm. ...
... The total antioxidant capacity (TAC) test aims to evaluate the ability of a compound to donate electrons to another molecule, which stabilizes it. [25] HA produced by S. zooepidemicus presented two-fold higher TAC than that of the commercial standard of HS (Table 3). The TAC was higher than that observed by Galinari et al. [25] for cell wall a-dmannan fractions from Kluyveromyces marxianus (1.27À8.91 mg ascorbic acid equivalent/g of sample). ...
... [25] HA produced by S. zooepidemicus presented two-fold higher TAC than that of the commercial standard of HS (Table 3). The TAC was higher than that observed by Galinari et al. [25] for cell wall a-dmannan fractions from Kluyveromyces marxianus (1.27À8.91 mg ascorbic acid equivalent/g of sample). ...
Hyaluronic acid (HA) is a biopolymer with applications in different areas such as medicine and cosmetics. HA is currently either isolated from animal sources or produced by microbial fermentation. Animal HA presents some disadvantages such as high cost and risk of viral cross-species or another infectious agent. In the present study, we evaluated the physicochemical characteristics and in vitro antioxidant capacity of HA produced by Streptococcus zooepidemicus CCT 7546. In addition, commercial sodium hyaluronate (SH) from an animal source was used as control. The microbial HA yield after purification was 69.8 mg/L. According to Fourier transform infrared spectroscopy, it was seen that bacterial and animal HA spectra are overlapped. The thermogravimetric analysis revealed that microbial HA was more stable than its equivalent from the animal source. However, scanning electron microscopy indicates that the purification method used in the animal product was more effective. Microbial HA showed activity in total antioxidant capacity (14.02 ± 0.38%), reducing power (18.18 ± 6.43%), DPPH radical-scavenging (5.57 ± 0.23 kmol TE/g), and hydroxyl radical-scavenging (28.39 ± 2.40%) tests. Therefore, in vitro antioxidant tests demonstrated that the antioxidant action mechanism occurs through scavenging reactive oxygen species (ROS) and donating electrons/hydrogen atoms.
... [65] However, this electron or hydrogen donating ability is not the main antioxidant mechanism for this α-d-mannan fraction. [66] The decrease in superoxide scavenging with increasing polysaccharide concentration is due to the formation of hydrogen bonds between polysaccharide molecules, resulting in fewer hydrogens available for interaction with ROS. [67] This is in line with the results of the study, that all samples showed higher inhibitory activity as the concentration of the samples increased due to more samples that can interact with free radicals. ...
... In this case, the smaller molecular weight and negatively charged structures exhibit the strongest antioxidant action, typically 75 kDa. [66] In conclusion, these results indicate that antioxidant activity cannot be inferred based on the category of yeast and mold, but rather based on the type of microorganism species used to produce mannoproteins in the order of Pichia sp, Rhizopus sp, Aspergillus sp, and Candida sp. ...
This study used tofu wastewater as medium to produce mannoprotein from Candida tropicalis (MCT), Pichia norvegensis (MPN), Aspergillus awamori (MAA), and Rhizopus oryzae (MRO). This study aimed to determine the optimum growth of yeast and mold in tofu wastewater as a medium for mannoprotein production. The purity was determined using FTIR and solid-state NMR spectroscopy. The structural differences were determined using scanning electron microscopy (SEM), and the antioxidant activity was measured using DPPH radical scavenging activity. The highest yield of extract was obtained upon the use of MPN (28.09 ± 6.4%, w/w), followed by MCT (18.73 ± 5.5%, w/w), MRO (2.75 ± 1.7%, w/w), and MAA (2.54 ± 1.7%, w/w). Moreover, FTIR spectroscopy confirmed that MCT, MPN, MAA, and MRO were typical mannoproteins with absorption band at 824, 824, 818, and 812 cm⁻¹, respectively. While the¹H NMR spectra revealed the presence of protons at 5.11–5.46 ppm which confirmed the presence of α-(1,2)-mannoprotein for MCT, α-(1,6)(1,2)-mannoprotein for MPN, and α-(1,6)-mannoprotein for MAA, and MRO. Mold-based mannoprotein has a smaller particle size than yeast-based mannoprotein, furthermore, at 4000 ppm, MCT had the greatest DPPH-free radical inhibition value of 49.89%, followed by MRO (44.34%), MAA (40.81%), and MPN (28.54%).
... The molecular weights of polysaccharides were determined with size-exclusion chromatography, as described earlier [37]. Ultrahydrogel columns 500 and 250 with 7.8 × 300 mm (Waters Corp., Massachusetts, USA) were connected in series to an Accela® HPLC (Thermo Scientific, Massachusetts, USA). ...
... Four tests (total antioxidant capacity, hydroxyl radical scavenging assay, ferrous chelating assay, and cupric chelating assay) were carried out as described by Presa et al. [38]. Reducing power, was carried out according to the method described by Galinari and co-workers [37]. The sixth method, H 2 O 2 radical scavenging assay, was determined based on Jesumani and co-workers [39]. ...
Antioxidants fucoidans from three seaweeds, Undaria pinnatifida (FUP), Macrocystis pyrifera (FMP) and Fucus vesiculosus (FFV) are sold commercially. However, it is unclear which fucoidan is the most potent antioxidant. Therefore, our objective was to compare the antioxidant activities of these fucoidans. For this purpose, six in vitro antioxidant tests were used, total antioxidant capacity, hydroxyl radical scavenging assay, ferrous and cupric chelating assay, reducing power and H2O2 scavenging assay. The data showed that the fucoidans had a low capacity to donate electrons, and a low capacity to chelate metals. The best activity obtained was in the scavenging of hydroxyl radical. When macrophages were exposed to H2O2 and fucoidans, MTT and live/dead assays showed that all fucoidans protected cells from oxidative damage. The survival rate of zebrafish embryos was significantly higher when exposed to H2O2 and fucoidans than H2O2 alone. In summary, the fucoidans evaluated were ranked according to their antioxidant activity as follows: FMP > FFV > FUP, and the results suggest that these fucoidans, mainly FMP, can be used in the formulation of medicines/foods.
... Among the common immunity pathways, TLRs and ILs are closely related to innate immunity. Mannan adjusts the immunity of the body through stimulates the immune response by binding to Dectin-2 receptors, promoting mitosis in macrophages, and inducing macrophages to produce nitric oxide, which in turn represented an inhibitory feedback [99][100][101]. Mannan binds to mannose receptor CD206 on the surface of macrophages and dendritic cells to enhance phagocytosis and binds to serum complement factor mannose-binding lectin to activate innate immunity [102][103][104]. TLRs and mannose binding lectin are pattern recognition receptors that participate in natural immunity with pathogen-related molecular patterns, and TLRs can initiate adaptive immune responses after activation [105]. ...
... In vitro studies, Galinari [100] extracted β-glucan and mannan from Kluyveromyces marxianus with 3% NaOH and 4 mol/L HCl, and fractionated polysaccharides with a centrifugal filter concentrator to obtain 5 different fractions of mannan KMM-1 (<10 kDa), KMM-2 (10 to <30 kDa), KMM-3 (30 to <50 kDa), KMM-4 (50 to <100 kDa), and KMM-5 (203 kDa). The antioxidant activity of the 5 fractions was evaluated by studying the initial (total antioxidant capacity and reducing capacity), propagation (copper and iron-chelating capacity), and termination (hydroxyl radical scavenging) aspects of the antioxidant process. ...
In order to solve the antibiotic resistance, the research on antibiotic substitutes has received an extensive attention. Many studies have shown that β-glucan and mannan from yeast cell wall have the potential to replace antibiotics for the prevention and treatment of animal diseases, thereby reducing the development and spread of antibiotic-resistant bacterial pathogens. β-Glucan and mannan had a variety of biological functions, including improving the intestinal environment, stimulating innate and acquired immunity, adsorbing mycotoxins, enhancing antioxidant capacity, and so on. The biological activities of β-glucan and mannan can be improved by chemically modifying its primary structure or reducing molecular weight. In this paper, the structure, preparation, modification, and biological activities of β-glucan and mannan were reviewed, which provided future perspectives of β-glucan and mannan.
... However, only a few studies have been conducted on protein production from Kluyveromyces sp. so far (Akanni et al., 2015;Galinari et al., 2018;Hajhosseini et al., 2020). Lukondeh et al. (2003) revealed that the emulsification properties of mannoprotein extracted from K. marxianus FII 510700 cell wall were like to those mannoprotein obtained from the cell walls of traditional source, S. cerevisiae. ...
... They observed that a mannan yield of 245.98 mg/100 mL could be obtained at the optimized conditions (pH: 4.99, glucose: 55.15 g/L, yeast extract: 9.35 g/L, and fermentation time: 168 h). Galinari et al. (2018) described that the cell wall polysaccharides such as α-D-mannan fractions from yeast K. marxianus CCT7735 showed hydroxyl-radical scavenging, superoxide radicals scavenging, copper-and iron-chelating activities, and reducing power as well as total antioxidant capacity. Thus, K. marxianus can be considered as an ideal source renewable and natural polysaccharides with pharmacological properties (antioxidant, antiproliferative, and immunostimulatory properties). ...
... The antiproliferative and anticancerous effect of polysaccharides varies with cell type. This observation may be attributed to the differences in the receptors present on different cell types that interact with different types of polysaccharides [59]. ...
One of the most unique non-conventional yeasts, Kluyveromyces marxianus, is rapidly gaining ground in biotechnology applications. K. marxianus possesses fast growth, thermotolerance, and a Crabtree-negative metabolism, features with a clear advantage over conventional yeasts like Saccharomyces cerevisiae. Additionally, it is diverse in carbon sources, utilizing lactate and xylose as well as lignocellulosic materials, which becomes critical in waste-utilizing and sustainable production industries. Besides the fact that K. marxianus has been useful in the production of valuable metabolites like β-galactosidase, ethanol, aroma compounds, and organic acids, its GRAS (Generally Recognized as Safe) designation makes K. marxianus a prime candidate for pharmaceutical and nutraceutical applications. This review summarizes a detailed description of K. marxianus’s biochemical and genetic features, its present applications, and future unexplored potentials such as probiotic development, vaccine production, bioremediation, and anticancer therapies. We also describe genetic tools that have been developed with improved metabolic pathways useful for new industry applications, making K. marxianus a resource in modern biotechnology. In sum, due to its unique features, K. marxianus appears to be a perfect alternative for areas such as biofuel production, biochemical synthesis, enzyme manufacturing, the dairy industry, and pharmaceuticals.
... Only mannan was obtained when phosphate was removed, while a KH 2 PO 4 excess produced phosphomannan [119]. Kluyveromyces marxianus CCT7735 cell wall α-D mannan fraction signified anti-proliferative and improved antioxidant activity, evidenced by the waning power potential, metal chelating, and hydroxyl radical scavenging activities [120]. ...
Mannan and outer structural yeast cell wall polysaccharides have recently garnered attention for their health defense and cosmetic applications. In addition, many studies have confirmed that yeast cell wall mannans exhibit various biological activities, such as antioxidant, immune regulation, reducing hyperlipidemia, and gut health promotion. This paper elucidates yeast cell wall mannan structural features, biological activities, underlying molecular mechanisms, and biosynthesis. Moreover, mannan-overproducing strategies through yeast strain engineering are emphasized and discussed. This review will provide a scientific basis for yeast cell wall mannan research and industrial applications.
... According to Abbas ( 2006 ) and Jaehrig et al. ( 2007 ), the high content of β-1,3-D-glucan and other β-glucans in the yeast cell wall explains its antioxidant activity, in addition to the presence of aforementioned enzymes (SOD, GPx, GR, Cta1, Ctt1). P articularl y for the case of K. marxianus species, Galinari et al. ( 2018 ) reported total antioxidant capacity as well as reducing po w er, elimination of hydr oxyl r adicals, and c helating activities of copper and iron in differ ent fr actions of α-d-mannan fr om the cell wall. Gil-Rodríguez et al. ( 2015 ) compared the antio xidant acti vity with reduction in DPPH (2,2-Diphenyl-1-picrylhydrazyl) activity of yeast strains with probiotic potential. ...
Non-Saccharomyces yeasts are unicellular eukaryotes that play important roles in diverse ecological niches. In recent decades, their physiological and morphological properties have been reevaluated and reassessed, demonstrating the enormous potential they possess in various fields of application. Non-Saccharomyces yeasts have gained relevance as probiotics, and in vitro and in vivo assays are very promising and offer a research niche with novel applications within the functional food and nutraceutical industry. Several beneficial effects have been described, such as antimicrobial and antioxidant activities and gastrointestinal modulation and regulation functions. In addition, several positive effects of bioactive compounds or production of specific enzymes have been reported on physical, mental and neurodegenerative diseases as well as on the organoleptic properties of the final product. Other points to highlight are the multiomics as a tool to enhance characteristics of interest within the industry; as well as microencapsulation offer a wide field of study that opens the niche of food matrices as carriers of probiotics; in turn, non-Saccharomyces yeasts offer an interesting alternative as microencapsulating cells of various compounds of interest.
... Studies have shown that cell wall a-D-mannan derived from Kluyveromyces can scavenge hydroxy radicals, and induced nitric oxide production in macrophages, suggestive of their immunostimulatory effects. (Galinari et al. 2018). ...
... The DPPH and ABTS free radical scavenging activities of yeast were demonstrated in an in vitro test with five strains of yeast isolated from traditional Korean fermented foods. The antioxidant activity of yeast is mainly due to the content of (1,3), (1,6)-β-D-glucan, and protein fractions located in the cell wall [49][50][51]. Glucans from different sources and molecular weights have different antioxidant activities [52]. The various specific scavenging activities of the yeast strains listed in Table 2 support these results. ...
Traditional yeast (Saccharomyces cerevisiae) has been used for its benefits in various fermentation processes; the benefits of non-Saccharomyces yeast as a material for food, feed, and pharmaceuticals have been studied recently. This study evaluated the anti-inflammatory activity and extracellular functional characteristics of wild-type yeasts isolated from traditional fermented foods (doenjang (common name: soybean paste) and nuruk) in Korea. The viability of the yeast and lipopolysaccharide (LPS)-stimulated RAWBlue™ cells was improved, similar to unstimulated RAWBlue™ cells, and the isolates demonstrated NF-κB inhibitory activity. Yeast suppressed the nitric oxide production in LPS-stimulated RAWBlue™ cells, which was attributed to the inhibition of iNOS or COX-2 mRNA expression depending on the strain. Although there were differences depending on the strain, the production of anti-inflammatory cytokines was reduced in the yeast and LPS-stimulated RAWBlue™ cells, some of which were demonstrated at the mRNA level. In addition, the isolates exhibited high antioxidant and antihypertensive activities (similar to the positive control), which varied depending on the strain. This suggests that yeast can be used for fermentation with enhanced antioxidant and antihypertensive activities. Furthermore, the isolates inhibited the growth of pathogenic Gram-negative bacteria, indicating that yeast can inhibit food spoilage and the growth of pathogenic bacteria during fermentation. Consequently, utilizing raw materials to cultivate yeast strains could be a promising avenue for developing functional foods to prevent and treat inflammatory reactions; such foods may exhibit antioxidant, antihypertensive, and antibacterial properties.
... Antioxidant peptides from K. marxianus have the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, 2,2 ′ -azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging and ferric reducing capacities, which has a function of cytoprotective properties against Caco2 cells under H 2 O 2 -modulated oxidative stress by activating the Kelch-like ECH-associated protein 1nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) signaling pathway and increasing the activity of antioxidants, such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX) [9]. The cell wall fractions of K. marxianus have antioxidant and immunostimulatory properties [10]. However, the effects of K. marxianus on KI and the related molecular mechanism remain unclear. ...
Objectives. The effects of Kluyveromyces marxianus on high-fat diet- (HFD-) induced kidney injury (KI) were explored. Methods. HFD-induced KI model was established using male C57BL/6 mice and treated with K. marxianus JLU-1016 and acid-resistant (AR) strain JLU-1016A. Glucose tolerance was evaluated via an oral glucose tolerance test (OGTT). KI was measured using Hematoxylin and Eosin (H&E) staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analysis. The chemical indexes were analyzed, including lipid profiles, inflammatory cytokines, and creatinine. The levels of Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) or phospho-NF-κB p65 (Ser536) and alpha inhibitor of NF-κB (IκBα) were measured using qPCR and Western blot. The gut microbiota was sequenced using high-throughput sequencing. Results. HFD induction increased OGTT value, KI severity, oxidative stress, inflammatory cytokines, oxidative stress, apoptotic rate, creatinine levels, and the expression of TLR4/NF-κB, phospho-NF-κB p65 (Ser536), and IκBα deteriorated lipid profiles (P
... The reduction may be due to the hydrolysis of mannans, as mentioned by Liu et al. [13], but also as a result of the loss of protein bound to mannans in these extracts. A study by Galinari et al. [61] reported that mannans extracted from fungus (Kluyveromyces marxianus) presented 5 different fractions with MW from 10-203 kDa. Although the extraction processes are different, they reveal the same two populations with a molecular weight ranging from 190-240 kDa populations. ...
Mannans are outstanding polysaccharides that have gained exponential interest over the years. These polysaccharides may be extracted from the cell wall of Saccharomyces cerevisiae, and recovered from the brewing or synthetic biology industries, among others. In this work, several extraction processes—physical, chemical and enzymatic—were studied, all aiming to obtain mannans from spent yeast S. cerevisiae. Their performance was evaluated in terms of yield, mannose content and cost. The resultant extracts were characterized in terms of their structure (FT-IR, PXRD and SEM), physicochemical properties (color, molecular weight distribution, sugars, protein, ash and water content) and thermal stability (DSC). The biological properties were assessed through the screening of prebiotic activity in Lactobacillus plantarum and Bifidobacterium animalis. The highest yield (58.82%) was achieved by using an alkaline thermal process, though the correspondent mannose content was low. The extract obtained by autolysis followed by a hydrothermal step resulted in the highest mannose content (59.19%). On the other hand, the extract obtained through the enzymatic hydrolysis displayed the highest prebiotic activity. This comparative study is expected to lay the scientific foundation for the obtention of well-characterized mannans from yeast, which will pave the way for their application in various fields.
... be 6.46 × 10 5 , 6.78 × 10 5 , and 6.98 × 10 5 Da, respectively.Fortin et al. (2017) reported the expression of mannoproteins in S. cerevisiae var. boulardii ATCC MYA-796, with Mw ranging from 10 2 to 10 4 Da.Galinari et al. (2018) isolated four yeast α-mannans from K. marxianus ...
This study investigated the interaction among Kluyveromyces marxianus G-Y4 (G-Y4), Lacticaseibacillus paracasei GL1 (GL1) and Lactobacillus helveticus SNA12 (SNA12) that isolated from Tibetan kefir grains. Additionally, the effects of G-Y4 on the growth and biofilm formation of GL1 and SNA12 were determined. The results indicated that G-Y4 promoted the growth of GL1 and SNA12 and improved their biofilm-forming ability. Furthermore, the dead cells of G-Y4 were found that could enhance bacterial biofilm formation, and the cell wall polysaccharide (CWPS) produced by G-Y4 was performed to be key substances that promote the formation of bacterial biofilms. Moreover, the structure of soluble cell wall polysaccharides (SCWP) and insoluble cell wall polysaccharide (NCWP) of G-Y4 were studied to determine their contribution to biofilm formation. Results showed that G-Y4-SCWP was α-mannan with the main chain of a →6)-α-d-Manp-(1→ unit and the branch structure of →2)-α-d-Manp-(1. At the same time, G-Y4-NCWP was a glucan rich in β-(1→3), β-(1→2), or β-(1→4) linkages.
... It is used for the production of endogenous enzymes such as β-xylosidase, β-glucosidase, and inulinase [51] as well as ingredients widely used in the food industry such as emulsifier mannoprotein [52] and baker's yeast [53]. Studies related to antioxidant activity have revealed that carbohydrates with low molecular weight show high antioxidant activity due to the degradation of saccharides by yeast [54]. A protein hydrolysate of K. marxianus shows cellular antioxidant activity [55]. ...
Oat (Avena sativa L.) is one of the most widely consumed cereal grains worldwide and is considered as an important cereal crop with high nutritional value and potential health benefits. With different bacterial strains, fermented oat extracts were examined for the antioxidant and antiaging effects on the skin after optimization of extraction conditions. Fermented oats contained high avenanthramides, and its function was investigated on matrix metalloproteinase-1 and collagen expression with human dermal fibroblast cells. After fractionation, butanol layers showed the highest avenanthramides contents. Therefore, the microbial fermentation of oats enhances the quality and content of functional ingredients of oats, which provide natural dietary supplements, antioxidants, and antiaging agents.
... be 6.46 × 10 5 , 6.78 × 10 5 , and 6.98 × 10 5 Da, respectively.Fortin et al. (2017) reported the expression of mannoproteins in S. cerevisiae var. boulardii ATCC MYA-796, with Mw ranging from 10 2 to 10 4 Da.Galinari et al. (2018) isolated four yeast α-mannans from K. marxianus ...
In this study, three yeast α-mannans (LZ-MPS, MC-MPS, and G-MPS) were extracted from different sources of Kluyveromyces marxianus. The total sugar content of the three α-mannans ranged from 91.13–97.10%, whereas no proteins were detected. A structural arrangement was proposed using ultraviolet spectroscopy, Fourier-transform infrared spectroscopy, and one-dimensional and two-dimensional nuclear magnetic resonance. The main chain of the three yeast α-mannans was formed by a →6)-α-D-Manp-(1→ unit, which was slightly different from the repeating unit of the branch structure. The prebiotic potential of LZ-MPS, MC-MPS, and G-MPS was assessed using in vitro fermentation with pure and faecal cultures. The three yeast α-mannans could be utilised as substrates for the growth of Lactobacillus and Lactococcus strains. In addition, the three yeast α-mannans markedly regulated the intestinal microbiota composition by increasing the relative abundances of Bacteroides, Parabacteroides, and Phascolarctobacterium and decreasing the abundance of pathogenic bacteria.
... Galinari et al. have shown the antioxidant and pro-apoptotic properties of the yeast Kluyveromyces marxianus, that presents a phylogenetic association with Saccharomyces cerevisiae. S. cerevisiae is generally employed in the classic nutrition industry [98]. In another study, the cytoprotective actions of β-glucan, originating from S. cerevisiae, played an important role in the prevention of genotoxicity [99]. ...
Background:
To date, most researchhas focused on the bacterial composition of the human microbiota. In this review, we synopsize recent data on the human mycobiome and cancer, highlighting specific cancer types based on current available evidence, presenting interesting perspectives and limitations of studies and laboratory methodologies.
Recent findings:
Head and neck cancer carcinoma (HNCC), colorectal carcinoma (CRC) and pancreatic ductal adenocarcinoma (PDA) have been associated with dissimilarities in the composition of mycobiota between cancer cases and non-cancer participants. Overall, fungal dysbiosis with decreased fungal richness and diversity was common in cancer patients; however, a specific mycobiotic signature in HNSCC or CRC has not emerged. Different strains of Candida albicans have been identified among cases with HNCC, whilst Lichtheimia corymbifera, a member of the Mucoraceae family, has been shown to predominate among patients with oral tongue cancer. Virulence factors of Candida spp. include the formation of biofilm and filamentation, and the secretion of toxins and metabolites. CRC patients present a dysregulated ratio of Basidiomycota/Ascomycota. Abundance of Malassezia has been linked to the occurrence and progression of CRC and PDA, particularly in animal models of PDA. Interestingly, Schizophyllum, a component of the oral mycobiome, may exhibit anti-cancer potential.
Conclusion:
The human mycobiome, per se, along with its interactions with the human bacteriome and the host, may be implicated in the promotion and progression of carcinogenesis. Fungi may be used as diagnostic and prognostic/predictive tools or treatment targets for cancer in the coming years. More large-scale, prospective, multicentric and longitudinal studies with an integrative multi-omics methodology are required to examine the precise contribution of the mycobiome in the etiopathogenesis of cancer, and to delineate whether changes that occur in the mycobiome are causal or consequent of cancer.
... All of them were carried out as described by Presa and co-workers [34]. The sixth method, reducing power, was carried out according to the method described by Galinari and co-workers [35]. ...
... These compounds delay or inhibit the formation of reactive species responsible for the chemical oxidization of other molecules. The formation of these reactive species happens in three stages: initiation, propagation, and termination [28]. Thus, the antioxidant properties of the film produced were analyzed through three methods, evaluating the initialization block (total antioxidant capacity), propagation (iron chelation), or termination (scavenging of the DPPH radical). ...
In this study, the potential of yellow mombin (Spondias mombin L.)–extracted pectin as a film-forming matrix for the elaboration of edible coatings was investigated. The films of chitosan, citric pectin, and carboxymethylcellulose (Sigma/USA) and natural pectin were prepared by casting. The film morphological characterization was performed by scanning electron microscopy (SME), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and atomic force microscopy (AFM). Additionally, total phenolic compounds (TPC), total antioxidant activity (TAC), DPPH scavenging capacity, and antimicrobial activity were assayed for the natural pectin–based films. The results showed that the film based on natural pectin presented a 46% degree of esterification that was higher than commercial (34%), showing its capacity of forming gels. The film formed by chitosan presented a very different behavior for loss of mass during TGA when compared to the other films, occurring a mass loss completely at 647.7 °C in 61 min. The value obtained from the concentration of total phenolics (mg GAE/100 g dried) found in the formulated film based on pectin was 3998.99 ± 42.64 and with solubility in water of almost 100%. Additionally, the scavenging of the DPPH radical with a value of 15.48 ± 1.48 μmol TE/g was found on the film based on natural pectin thus showing antioxidant capacity. Finally, this film showed less significant mechanical properties when compared to other films and a good pronounced antimicrobial effect against the gram-negative bacteria tested. Therefore, it could be potentially used for producing food-active packages.
... The band near 2897.08 cm −1 revealed the CH stretching vibration of CH 2 groups. In addition, the band at 1643.35 cm −1 was associated with the carbonyl group (C = O; Galinari, Almeida-Lima, Macedo, Mantovani, & Rocha, 2018). Protein residues were recorded in the region of 1,400 to 1,700 cm −1 (Piotrowska & Masek, 2015), whereas the band at 1039.63 cm −1 corresponded to the C-O stretching vibrations in alcohols (C. ...
This study was intended to investigate physico‐chemical, rheological, and emulsifying properties of oil‐in‐water emulsions prepared from the Kluyveromyces marxianus mannoprotein (KMM). Also, the stress‐response function of the KMM emulsions was compared with that of the whey protein concentrate (WPC) emulsions in terms of zeta potential, size, and rheology. The stress experiments were conducted at different pH (3 to 9), ionic composition (0 to 500 mM NaCl), and temperatures (30 to 90 °C). The extracted KMM with a molecular weight of 107.2 kDa had 28.8% proteins and 68.22% carbohydrates. With increasing the KMM concentration to 1.5% (w/w), the zeta potential, droplet size, and apparent viscosity of the emulsions reached −35 mV, ∼1 μ, and ∼9 mPa·s, respectively. After applying pH, ionic composition, and temperature, the KMM emulsions were more stable than the WPC emulsions. In conclusion, KMM can be used as a bioemulsifier and be more effective in stabilizing emulsions than WPC.
Practical Application
Yeasts are a rich source of natural materials. In this study, we extracted mannoproteins from the yeast cell wall and evaluated their functional properties to be used as an emulsifier in oil‐in‐water emulsions. The results of this study confirm that the yeast‐derived mannoproteins are good at stabilizing these emulsions either in the presence or absence of different environmental conditions.
... All of them were carried out as described by Presa and co-workers [34]. The sixth method, reducing power, was carried out according to the method described by Galinari and co-workers [35]. ...
A 12.4 kDa laminarin (LM) composed of β(1→3)-glucan with β(1→6)-branches was extracted from brown seaweed Lobophora variegata and modified via carboxylation using dielectric barrier discharge (LMC), conjugation with gallic acid (LMG), and sulfation (LMS). Analyses of the chemical composition of LMC, LMG, and LMS yielded 11.7% carboxyl groups, 1.5% gallic acid, and 1.4% sulfate content, respectively. Antioxidant activities of native and modified laminarins were assessed using six different in vitro methods. Sulfation stopped the antioxidant activities of LM. On the other hand, carboxylation improved cooper chelation (1.2 times). LMG was found to be a more efficient antioxidant agent than LM in terms of copper chelation (1.3 times), reducing power (1.3 times), and total antioxidant capacity (80 times). Gallic acid conjugation was further confirmed using Fourier transform infrared spectroscopy (FT-IR) and one- and two-dimensional NMR spectroscopy analyses. LMG also did not induce cell death or affect the cell cycle of Madin–Darby canine kidney (MDCK) cells. On the contrary, LMG protected MDCK cells from H2O2-induced oxidative damage. Taken together, these results show that LMG has the potent antioxidant capacity, and, therefore, potential applications in pharmacological and functional food products.
... Indeed, the NO is defined as an endogenous free radical produced by the macrophages during the inflammatory response due to the membrane receptors activation after contact with bacterial components poly and lipopolisacarides . These bacterial components interact with macrophages receptors promoting an intracellular signaling cascade that activates the NO synthase enzyme NOS and, thus, enables the production of NO from the L-arginine 30,31 . To this regard, the NO has an important role on the inflammation and infectious processes, once it induces lipid peroxidation, DNA damage and protein oxidation because of its reaction with other free radicals reactive oxygen species -ROS and/or hydrogen peroxide -H 2 O 2 during the host defense 32 . ...
Bullfrog oil (BFO) is a natural product from the adipose tissue of the amphibian Rana catesbeiana Shaw, a bio-product rich in polyunsaturated fatty acids, which claims anti-inflammatory activity. The objective of this work was to evaluate the cytotoxicity and the anti-inflammatory activity of BFO using in vivo and in vitro assays. Thus, the in vitro cytotoxicity was assessed by the MTT assay. Additionally, the in vivo anti-inflammatory activity was performed by the carrageenan-induced paw edema model in Wistar rats, followed by histological analysis. Moreover, the BFO effect on inflammatory pathways was investigated by in vitro evaluation of the nitric oxide (NO) synthesis, and type-6 interleukin (IL-6) and tumor-necrosisfactor (TNF) levels. In vivo experiments showed that BFO administered by intragastric route produced a significant anti-inflammatory effect, which was as substantial as indomethacin, the positive control. Histopathological analysis confirmed these results, showing the absence of the edema and minimal signs of inflammation in the paws of rats treated with BFO. The MTT results showed that BFO at all tested concentrations had no toxic effect against a macrophage cell line, not affecting the cell viability. In addition, after 48 hours of treatment, the BFO itself and its blend with Cetiol®-V (1:1v/v) at 200 µg.mL–1 were able to reduce the NO synthesis, and the IL-6 and TNF levels up to 35 ± 2%, 40 ± 6%, and 12 ± 3%, respectively. Therefore, these results provide unprecedented scientific evidence of the anti-inflammatory effect of BFO, suggesting its potential as a new candidate for the development of pharmaceutical products with antiinflammatory activity.
... K. lactis M3 reported in this study showed a high antioxidant capacity, especially ferric reducing power (FRAP assay) when it was compared with a purified strong antioxidant. The antioxidant capacity of K. lactis M3 must rely on its structural (cell wall) or soluble (antioxidant enzymes) compounds able to donate electrons or hydrogen atoms to another molecule [52,53], thereby stabilizing free radicals and blocking radical chain reactions to the chemical oxidation of other molecules. In a previous study, Ceugniez et al. [54] observed a high antioxidant capacity of K. marxianus S-02-5 that also justified its evaluation as a good probiotic. ...
The aim of this study was to analyze the probiotic potential, fatty acid composition and immunostimulant activities of Kluyveromyces lactis M3 isolated from a hypersaline sediment. For this purpose, K. lactis M3 resistance to different pH, salinities and bile, as well as its antioxidant capability were assayed. Furthermore, total fatty acid composition of the yeast was determined where the dominant fatty acids were palmitic, palmitoleic, oleic and linoleic acids. K. lactis M3 showed no cytotoxic effects on peripheral blood leukocytes. During an in vivo experiment in gilthead seabream (Sparus aurata), dietary K. lactis M3 supplemented at 0.55 or 1.1% of the basal diet enhanced bactericidal activity against Vibrio parahaemolyticus N16, V. harveyi Lg 16/00, and V. anguillarum CECT 43442 compared to fish fed commercial diet (control group). Finally, nitric oxide production, peroxidase activity and skin mucus lectin union levels strongly increased in fish fed K. lactis M3 with respect to the control group. The results suggested that the yeast K. lactis M3 had exhibited high antioxidant capability, and its dietary administration at 0.55 or 1% basal diet had immunostimulant activity for gilthead seabream. For all these reasons, it should be considered an appropriate probiotic candidate for the aquaculture fish industry.
... Several of these molecules have been shown to have biological/pharmacological properties, such as the antithrombotic fucans of the seaweed S. schröederi [24,26], which also have antimigratory activity [27] and antiangiogenic activity [17], the antitumor fucans of the seaweed Dictyopteris delicatula [28], the anti-nociceptive and anti-inflammatory fucoidans of the seaweed Dictyota menstrualis [29], and fucans extracted from Dictyopteris justii seaweed that are capable of decreasing the formation of calcium oxalate crystals [19]. In addition, fucans of Canistrocarpus cervicornis have antioxidant activity [30]. ...
Some antioxidant compounds decrease the amount of intracellular reactive oxygen species (ROS) and consequently reduce the deleterious effects of ROS in osteoblasts. Thus, these compounds fight against osteoporosis. Brown seaweeds are a rich source of antioxidant fucose-containing sulfated polysaccharides (fucans and fucoidans). We obtained six fucoidans (FRFs)—F0.3, F0.5, F0.7, F1.0, F1.5, and F2.1—from Dictyota mertensii by proteolytic digestion followed by sequential acetone precipitation. Except for F0.3, all FRFs showed antioxidant activity in different in vitro tests. In pre- osteoblast-like cells (MC3T3-L1) exposed to H2O2-oxidative stress, caspase-3 and caspase-9 were activated, resulting in apoptosis of the cells. We also observed a decrease in superoxide dismutase (SOD) and alkaline phosphatase (ALP) activity. The antioxidant FRFs protected the cells from the oxidative damage caused by H2O2, decreasing intracellular ROS and caspase activation, and increasing SOD activity. The most effective protection against damage was provided by F0.7, F1.5, and F2.1. At 0.5 mg/mL, these FRFs also suppressed the H2O2-mediated inhibition of ALP activity. The data indicated that FRFs F0.7, F1.5, and F2.1 from D. mertensii were antioxidants that protected bone tissue from oxidative stress and could represent possible adjuvants for the treatment of bone fragility through counteracting oxidative phenomena.
... Conversely, most of the studies have mainly focused on particular activities of postbiotics, and little attention has been paid to their multifunctional properties. For instance, combined properties such as antioxidant, immunomodulatory, anti-inflammatory, or antiproliferative activity have been reported for exopolysaccharides produced by Weissella confusa strains [16], and probiotic cell-free supernatants [17] and cell wall α-D-mannan fractions from the yeast Kluyveromyces marxianus [18]. Such multifunctionality may be preferred over a single activity because multifunctional postbiotics could target simultaneously multiple physiological pathways [1]. ...
In this study, a global metabolite profile using Raman spectroscopy analysis was obtained in order to predict, by an in silico prediction of activity spectra for substance approach, the bioactivities of the intracellular content (IC) and cell wall (CW) fractions obtained from Lactobacillus casei CRL 431 and Bacillus coagulans GBI-30 strains. Additionally, multifunctional in vitro bioactivity of IC and CW fractions was also assessed. The metabolite profile revealed a variety of compounds (fatty acids, amino acids, coenzyme, protein, amino sugars), with significant probable activities (Pa > 0.7) as immune-stimulant, anti-inflammatory, neuroprotective, antiproliferative, immunomodulator, and antineoplastic, among others. Moreover, in vitro assays exhibited that both IC and CW fractions presented angiotensin-converting enzyme–inhibitory (> 90%), chelating (> 79%), and antioxidant (ca. 22–57 cellular antioxidant activity units) activities. Our findings based on in silico and in vitro analyses suggest that L. casei CRL 431 and B. coagulans GBI-30 strains appear to be promising sources of postbiotics and may impart health benefits by their multifunctional properties.
The human microbiome, including bacteria, fungi, archaea, and viruses, is intimately linked to both health and disease. The relationship between bacteria and disease has received much attention and intensive investigation, while that of the fungal microbiome, also known as mycobiome, has lagged far behind bacteria. There is growing evidence showing mycobiome dysbiosis in cancer patients, and certain cancer-specific fungi may contribute to cancer progression by interacting with both host and bacteria. It was also demonstrated that the role of fungi-derived products in cancer should also not be underestimated. Therefore, investigating how fungal pathogenesis contributes to the onset and spread of cancer would yield crucial information for cancer diagnosis, prevention, and anti-cancer therapy.
Fungal dysbiosis is increasingly recognized as a key factor in cancer, influencing tumor initiation, progression, and treatment outcomes. This review explores the role of fungi in carcinogenesis, with a focus on mechanisms such as immunomodulation, inflammation induction, tumor microenvironment remodeling, and interkingdom interactions. Fungal metabolites are involved in oncogenesis, and antifungals can interact with anticancer drug, including eliciting potential adverse effects and influencing immune responses. Furthermore, mycobiota profiles have potential as diagnostic and prognostic biomarkers, emphasizing their clinical relevance. The interplay between fungi and cancer therapies can impact drug resistance, therapeutic efficacy, and risk of invasive fungal infections associated with targeted therapies. Finally, emerging strategies for modulating mycobiota in cancer care are promising approaches to improve patient outcomes.
Fermented camel milk, named shubat in Central Asia, is historically and culturally important because it is mainly consumed by Kazakh people who live not only in Kazakhstan but also in close neighboring countries. However, despite its cultural and dietetic significance for this local population, research on its composition and processing technology and the richness of its microflora is relatively scarce. The present review of this product, which is an important beverage in the Kazakh culture, provides up-to-date information regarding its main components and their variability according to different factors, surveys recent changes in the processing technologies for making it using modern techniques, and explores the biodiversity of its microflora. It was reported that the protein, vitamin C, and calcium contents in shubat vary between 1.19 and 5.63%, 28 and 417 mgL−1, and 1.03 and 1.88 gL−1. The lactose content totally disappears. Shubat contains a complex microbial consortium that contributes to its strong reputation for health benefits, but a scientific demonstration of these claims has only been partially achieved.
Non-conventional yeast species, or non-Saccharomyces yeasts, are increasingly recognized for their involvement in fermented foods. Many of them exhibit probiotic characteristics that are mainly due to direct contacts with other cell types through various molecular components of their cell wall. The biochemical composition and/or the molecular structure of the cell wall components are currently considered the primary determinant of their probiotic properties. Here we first present the techniques that are used to extract and analyze the cell wall components of food industry-related non-Saccharomyces yeasts. We then review the current understanding of the cell wall composition and structure of each polysaccharide from these yeasts. Finally, the data exploring the potential beneficial role of their cell wall components, which could be a source of innovative functional ingredients, are discussed. Such research would allow the development of high value-added products and provide the food industry with novel inputs beyond the well-established S. cerevisiae.
BACKGROUND
Fresh‐cut fruit are convenient ready‐to‐eat products increasingly demanded by consumers, but highly susceptible to oxidation. To increase the shelf life of these products, this industry is currently facing the challenge of finding sustainable natural preservatives capable of maintaining fresh‐cut fruit quality while meeting consumers’ expectations regarding health and environmental concerns.
RESULTS
In this work, fresh‐cut apple slices were treated with two antioxidant extracts derived from industrial by‐products: a phenolic‐rich extract produced from sugarcane straw (PE‐SCS) and applied at 15 g L⁻¹, and a mannan‐rich extract obtained from brewer's spent yeast (MN‐BSY) applied at two concentrations: 1 and 5 g L⁻¹. PE‐SCS, having a brown color, imparted a brownish hue to the fruit and increased the browning rate during storage, and not even the initial robust antioxidant response (high superoxide dismutase, catalase, ascorbate peroxidase and guaiacol peroxidase activities), prevented oxidation. Fruit treated with MN‐BSY extract at 5 g L⁻¹ showed lower color loss rate and higher polyphenol oxidase inhibition, while at 1 g L⁻¹ it showed lower firmness loss rate and lower lipid peroxidation after 6 days of storage.
CONCLUSION
The results showed that PE‐SCS triggers a potent antioxidant response in fresh‐cut fruit and, despite it imparting a brown color to the fruit at 15 g L⁻¹, it may have potential for application at lower concentrations. Regarding MN‐BSY, it generally decreased oxidative stress, but its effect on quality maintenance was dependent on the concentration and, thus, to confirm its potential as a fruit preservative more concentrations must be tested. © 2023 Society of Chemical Industry.
Hyaluronic acid (HA), an anionic, non-sulfated glycosaminoglycan, has several clinical applications. This study examines several downstream methods for purifying HA with maximum recovery and purity. Following the fermentation of Streptococcus zooepidemicus MTCC 3523 to produce HA, the broth was thoroughly purified to separate cell debris and insoluble impurities using a filtration procedure and a variety of adsorbents for soluble impurities. Nucleic acids, proteins with high molecular weight, were successfully removed from the broth using activated carbons and XAD-7 resins. In contrast, insoluble and low molecular weight impurities were removed using diafiltration, with HA recovery of 79.16% and purity close to 90%. Different analytical and characterization procedures such as Fourier transform-infrared spectroscopy, X-ray diffraction, nuclear magnetic resonance, and scanning electron microscopy validated the presence, purity, and structure of HA. Microbial HA showed activity in tests for 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical-scavenging (4.87 ± 0.45 kmol TE/g), total antioxidant capacity (13.32 ± 0.52%), hydroxyl radical-scavenging (32.03 ± 0.12%), and reducing power (24.85 ± 0.45%). The outcomes showed that the precipitation, adsorption, and diafiltration processes are suitable for extracting HA from a fermented broth under the chosen operating conditions. The HA produced was of pharmaceutical grade for non-injectable applications.
The microbiome may impact cancer development, progression and treatment responsiveness, but its fungal components remain insufficiently studied in this context. In this review, we highlight accumulating evidence suggesting a possible involvement of commensal and pathogenic fungi in modulation of cancer-related processes. We discuss the mechanisms by which fungi can influence tumour biology, locally by activity exerted within the tumour microenvironment, or remotely through secretion of bioactive metabolites, modulation of host immunity and communications with neighbouring bacterial commensals. We examine prospects of utilising fungi-related molecular signatures in cancer diagnosis, patient stratification and assessment of treatment responsiveness, while highlighting challenges and limitations faced in performing such research. In all, we demonstrate that fungi likely constitute important members of mucosal and tumour-residing microbiomes. Exploration of fungal inter-kingdom interactions with the bacterial microbiome and the host and decoding of their causal impacts on tumour biology may enable their harnessing into cancer diagnosis and treatment.
Over the last years, polysaccharides have been linked to antioxidant effects using both in vitro chemical and biological models. The reported structures, claimed to act as antioxidants, comprise chitosan, pectic polysaccharides, glucans, mannoproteins, alginates, fucoidans, and many others of all type of biological sources. The structural features linked to the antioxidant action include the polysaccharide charge, molecular weight, and the occurrence of non-carbohydrate substituents. The establishment of structure/function relationships can be, however, biased by secondary phenomena that tailor polysaccharides behavior in antioxidant systems. In this sense, this review confronts some basic concepts of polysaccharides chemistry with the current claim of carbohydrates as antioxidants. It critically discusses how the fine structure and properties of polysaccharides can define polysaccharides as antioxidants. Polysaccharides antioxidant action is highly dependent on their solubility, sugar ring structure, molecular weight, occurrence of positive or negatively charged groups, protein moieties and covalently linked phenolic compounds. However, the occurrence of phenolic compounds and protein as contaminants leads to misleading results in methodologies often used for screening and characterization purposes, as well as in vivo models. Despite falling in the concept of antioxidants, the role of polysaccharides must be well defined according with the matrices where they are involved.
Chemotherapy-induced peripheral neuropathic pain (CIPNP) is a progressive and disturbing peripheral neuropathy with currently no effective treatment. Aberrant production of reactive oxygen species (ROS) in macrophages near peripheral nerves plays a dominant role in CIPNP; however, traditional ROS scavengers have difficulty maintaining viability to target macrophages in vivo. Mannose-coated superparamagnetic iron oxide nanoparticles (mSPIONs) were synthesized to treat CIPNP. The anti-ROS and anti-inflammatory effects of mSPIONs were assessed in J774A.1 cells and sciatic nerves in a nociception mouse model induced with vincristine (VCR). We found that the mSPIONs significantly reduced ROS levels in vitro and in vivo. Furthermore, mSPIONs administration specifically reduced IL-6 and TNF-α levels in macrophages near the sciatic nerve and relieved VCR-induced peripheral neuropathic pain. Inhibition of the VCR-upregulated HIF1α/NF-κB signaling pathway may be involved in the alleviation of inflammation. These results provide a new approach for relieving CIPNP using a nanozyme.
Mannans are polysaccharides whose physicochemical and biological properties render them commercialization in several products. Since these properties are strongly dependent on production conditions, the present study aims to assess the impact of different drying technologies - freeze (FDM) and spray drying (SDM) - on the structural, physicochemical, and biological properties of mannans from Saccharomyces cerevisiae. Structural analysis was assessed by FT-IR, PXRD and SEM, whereas physicochemical properties were evaluated based on sugars, protein, ash and water contents, solubility, and molecular weight distribution. Thermal behaviour was analysed by DSC, and antioxidant activity by DPPH and ABTS assays. The parameters which revealed major differences, in terms of structural and physicochemical properties regarded morphology (SEM), physical appearance (colour), moisture (3.6 ± 0.1 % and 11.9 ± 0.6 % for FDM and SDM, respectively) and solubility (1 mg/mL for FDM and 25 mg/mL for SDM). Nevertheless, these differences were not translated into the antioxidant capacity.
Mannans has been attracted the interest in various sectors due to its promising applications. The low toxicity of mannans allows for their use in cosmetics, pharmaceutical, and biomedical industries. In this study, the α-D-mannan extraction conditions from Aureobasidium pullulans by alkaline extraction were optimized using a Box-Behnken design (BBD). The effect of temperature (°C), pH and extraction time (hours) on the yield of α-mannan was investigated. The conditions that produced the highest yield (26%) were a temperature of 92 °C, extraction time of 3 h and pH 13. In addition, the α-D-mannan structure was confirmed by methylation analysis, 1D and 2D NMR spectroscopic analysis, and GC-MS.
Microbe-based cancer immunotherapy has recently emerged as a hot topic for cancer treatment. However, serious limitations remain including infection associated side-effect and unsatisfactory outcomes in clinic trials. Here, we fabricate different sizes of nano-formulations derived from yeast cell wall (YCW NPs) by differential centrifugation. The induction of anticancer immunity of our formulations appears to inversely correlate with their size due to the ability to accumulate in tumor-draining lymph node (TDLN). Moreover, we use a percolation model to explain their distribution behavior toward TDLN. The abundance and functional orientation of each effector component are significantly improved not only in the microenvironment in tumor but also in the TDLN following small size YCW NPs treatment. In combination with programmed death-ligand 1 (PD-L1) blockade, we demonstrate anticancer efficiency in melanoma-challenged mice. We delineate potential strategy to target immunosuppressive microenvironment by microbe-based nanoparticles and highlight the role of size effect in microbe-based immune therapeutics.
Mannan oligosaccharide is one of the major components of the yeast cell wall. In the present study, the production, characterization, and bioactivity of yeast mannan were investigated. Four indigenous yeast isolates were obtained from various kinds of juice collected from local markets in Al-Ahsa, KSA, and analyzed using morphological and biochemical methods. Isolate RY1 showed the highest production of mannan. RY1 was identified as Saccharomyces cerevisiae based on morphological characteristics and sequencing of the 18S rRNA gene (GenBank accession number LC479088.1). Mannan-RY1 was further characterized by polymer analytical methods, ¹³C and ¹H nuclear magnetic resonance spectroscopy (NMR), and infrared spectroscopy (IR). Interestingly, the mannan extracted from RY1 showed a significant ability to scavenge hydroxyl radicals and superoxide anions. In addition, mannan was found to have pronounced anti-tumor activity against liver (HepG2) and breast cancer (MCF7) cell lines. The results presented in this study confirm the bio-therapeutic activity of S. cerevisiae mannan, which could be used as a potential drug for cancer treatment.
Background
Although bullfrog oil (BFO) exerts anti-inflammatory effects, it has undesirable properties limiting its use.
Methodology
BFO nanocapsules (BFONc) were produced through nanoprecipitation, and their physicochemical and morphological properties were characterized. To evaluate the biocompatibility of the formulation, a mitochondrial activity evaluation assay was conducted, and cell uptake was assessed. The in vitro anti-inflammatory activity was evaluated by measuring reactive oxygen species (ROS), nitric oxide (NO), type-6 interleukin (IL-6), and tumor necrosis factor (TNF) levels. The in vivo anti-inflammatory effect was assessed by quantifying myeloperoxidase (MPO) levels using the carrageenan-induced paw edema model.
Results
BFONc showed a particle size of 233 ± 22 nm, a polydispersity index of 0.17 ± 0.03, and a zeta potential of −34 ± 2.6mV. BFONc revealed remarkable biocompatibility and did not induce changes in cell morphology. Furthermore, BFONc decreased ROS levels by 81 ± 4%; however, NO level increased by 72 ± 18%. TNF and IL-6 levels were reduced by approximately 10% and 90%, respectively. Significant in vivo anti-inflammatory activity was observed compared to dexamethasone. MPO levels were reduced up to 2 MPOs/mg.
Conclusion
Taken together, the results pointed out the remarkable biocompatibility and anti-inflammatory effects of BFONc.
Yeast mannans from Saccharomyces cerevisiae (123.2 kDa, 40.5 kDa and 21.3 kDa) were prepared. The scavenging abilities of Fe2+, OH˙, and O2˙- and protective capacities against lipid peroxidation and oxidative DNA damage increased with the reduction of the molecular weights of yeast mannans. The highest scavenging abilities of Fe2+, OH˙ and O2˙- (25.32%, 70.8%, and 61.5%) were observed with YM-90, and it showed an anti-lipid peroxidation capacity of 65.82%, which was much stronger than that of vitamin C (VC), with a thiobarbituric acid-reactive substance (TBARS) inhibition rate of 80.41%. However, the highest DPPH scavenging rate (88.7%) was exhibited by YM-30. In addition, the growth-promoting effect of yeast mannans on Lactobacillus strains was further confirmed, and a 54.2% increment of Lactobacillus plantarum ZWR5 cell viability was achieved by YM-90. The results indicated the potential industrial applications of this yeast mannan technology in therapeutic and nutraceutical production.
Fungi are versatile living microbe that has a wide range of uses. Fungi comprised of moulds and yeasts. The yeasts have been recognized to play a significant role in beverage industries. Among the yeasts, Saccharomyces cerevisiae and Kluyveromyces marxianus are the most important representatives. Their utilization is largely determined by their reproductive characteristics, which can also be proved by mathematical relationships, such as generation time and maximum specific rate of growth. They are preferred for use in the food, feed, cosmetics and many other areas. Their advantages are mainly due to their metabolic processes and cell growth, which can be used to produce many well-known products such as single cell protein. In some cases, they can also cause deterioration. It is hoped that Saccharomyces cerevisiae and Kluyveromyces marxianus may be the focus of research interest by demonstrating the importance of the yeast species.
The human gut is mainly habited by a staggering amount and abundance of bacteria as well as fungi. Gut dysbiosis is believed as a pivotal factor in colorectal cancer (CRC) development. Lately increasing evidence from animal or clinical studies suggested that fungal disturbance also contributed to CRC development. This review summarized the current status of fungal dysbiosis in CRC and highlighted the potential tumorigenic mechanisms of fungi. Then the fungal markers and some therapeutic strategies for CRC were discussed. It would provide a better understanding of the correlation of mycobiota and CRC, and modulating fungal community would be a promising target against CRC.
Background
Natural products constitute more than half of all biomolecules lately being used in clinical settings. Mannoprotein derived from the yeast cell wall has found full biotechnological applications.
Objective
This study was intended to investigate antioxidant, anticancer, and toxicological properties of Kluyveromyces marxianus mannoprotein (KM).
Methods
The KM extract was obtained through a sequence of operations, including centrifugation for cell isolation, precipi-tation with potassium citrate/ sodium metabisulfite, and recovery and purification. Its antioxidant, growth inhibition, macro-phage mitogenic, and toxic activities were evaluated for its future use in the biomedical field.
Results
Significantly inhibitory effects of KM were obtained on reactive species. It showed antiproliferative activity against HeLa (human cervical adenocarcinoma) and MCF-7 (human breast cancer) cell lines with no toxic effects on HUVECs (human umbilical vein endothelial cells). The in vitro model of CHO-K1 (Chinese hamster ovary) cell lines did not show the cytotoxic and genotoxic of KM. Also, it enhanced macrophage activity in terms of nitric oxide (NO) production and viabil-ity. No sign of acute toxicity was found in BALB/c mice, and body weight remained unchanged in guinea pigs over three months.
Conclusion
Comprehensive biological evaluations in this study are expected to expand the potential of KM as a natural material.
Ethnopharmacological relevance
Commiphora leptophloeos (Mart.) J.B. Gillett (Burseraceae) is a medicinal plant native from the brazilian northeast caatinga biome, known popularly as “imburana” or “imburana-de-cambão”. The leaves of C. leptophloeos are widely used in folk medicine in the treatment of various inflammatory disorders. However, there is no scientific evidence to justify their popular use.
Aim of the study
This approach aimed to characterize the phytochemical profile of hydroethanolic leaf extract, as well as evaluate the anti-inflammatory and antioxidant potential activity and to investigate the acute toxicity with pre-clinical in vitro and in vivo methodologies.
Materials and methods
The phytochemical profile was characterized by UPLC-MS and FIA-ESI-IT-MS/MS. The in vitro anti-inflammatory potential the hydroethanolic extract of C. leptophloeos (1, 10, 100 and 200 μg/mL) was investigated by lipopolysaccharide (LPS) induced nitric oxide assay, in order to analyze the potential decrease of nitric oxide (NO) production. For carrageenan-induced paw edema and zymosan-induced air pouch models, the extract (100, 200 and 400 mg/kg) was administrated by intragastric gavage (i.g.) route and used for evaluating the anti-inflammatory effect in vivo. Related to the first animal model, the antiedematogenic activity and myeloperoxidase (MPO) levels could be investigated. In addition, the zymosan-induced air pouch model allowed the analyses of leukocytes migration, total MPO, malondialdehyde (MDA) and cytokines (TNF-α and IL-10) levels. The toxicity in vitro of the extract (1, 10, 100 and 200 μg/mL) was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and acute toxicity in vivo was tested using the extract at 2000 mg/kg by i. g. route.
Results
The phytochemical analyses of C. leptophloeos leaf extract pointed the presence of six glycosylated flavonoids, identified as orientin, isoorientin, vitexin and isovitexin, quercetrin and isoquercitrin. A decrease of NO in vitro was noticed by the use of the extract in the LPS-induced nitric oxide assay and an expressive reduction of the paw-edema followed by a decrease of myeloperoxidase activity at doses of 200 and 400 mg/kg. The zymosan-induced air pouch model indicated that the extract, in all doses, significantly reduced the leukocytes migration, total protein concentration, MPO and MDA levels. The levels of cytokines were verified by the administration of extract in this model, revealing a lower of TNF-α level and an increase of the IL-10 production. In the toxicity study, the MTT assay evidenced no cytotoxicity of the tested concentrations and acute toxicity in vivo test did not result in any sign of toxicity and mortality or significant changes on the biochemical parameters.
Conclusion
Based on these results, is possible suggest that the anti-inflammatory activity revealed in this approach can be related to the modulating the level of cytokine, decrease of TNF-α, increase of IL-10 in vivo and also the inhibition of the production of nitric oxide RAW 264.7 activated by LPS. These results demonstrate the potential anti-inflammatory effect C. leptophloeos leaf extrat in inflammatory in vivo models, supporting its use in folk medicine for treatment of inflammatory diseases. Finally, glycosylated flavonoids can be responsible, at least in part, for this effect.
The fractionation of agroindustrial and forest residues is a premise of the biorefinery concept. Thus, the present study focuses on pretreatments (hydrothermal and alkaline) and detoxification processes in order to transform green coconut fiber (GCF) into cellulose-rich material, dye biosorbent, bioactive phenolic compounds, lignin and arabinoxylan. The adsorption onto Amberlite XAD-7HP resin allowed the best recovery of phenolic compounds from hydrothermal pretreatment liquor, which presented potent antioxidant activities such as inhibition of hydroxyl and superoxide radicals of 77.05% and 76.88%, respectively. Acid precipitation was effective to recover 41.23% of the initial lignin content from alkaline pretreatment liquor. The detoxified hydrothermal pretreatment liquor was used as an additional source of glucose, increasing the final concentration of ethanol by 79.6% in simultaneous saccharification and fermentation of delignified GCF. Using delignified GCF as biosorbent, made it possible to obtain a static adsorption capacity of 200 mg of methylene blue dye per gram of biosorbent and good recyclability in dynamic experiments. Therefore, the proposed methodology guarantees a practical way of manufacturing value-added products from lignocellulosic materials.
Lipid peroxidation can be described generally as a process under which oxidants such as free radicals attack lipids containing carbon-carbon double bond(s), especially polyunsaturated fatty acids (PUFAs). Over the last four decades, an extensive body of literature regarding lipid peroxidation has shown its important role in cell biology and human health. Since the early 1970s, the total published research articles on the topic of lipid peroxidation was 98 (1970-1974) and has been increasing at almost 135-fold, by up to 13165 in last 4 years (2010-2013). New discoveries about the involvement in cellular physiology and pathology, as well as the control of lipid peroxidation, continue to emerge every day. Given the enormity of this field, this review focuses on biochemical concepts of lipid peroxidation, production, metabolism, and signaling mechanisms of two main omega-6 fatty acids lipid peroxidation products: malondialdehyde (MDA) and, in particular, 4-hydroxy-2-nonenal (4-HNE), summarizing not only its physiological and protective function as signaling molecule stimulating gene expression and cell survival, but also its cytotoxic role inhibiting gene expression and promoting cell death. Finally, overviews of in vivo mammalian model systems used to study the lipid peroxidation process, and common pathological processes linked to MDA and 4-HNE are shown.
The influence of medium composition and cultural conditions on simultaneous yield of mycelia, intracellular polysaccharide, adenosine, and mannitol by Cordyceps militaris CGMCC 2909 was investigated with desirability functions in this study. An optimization strategy based on the desirability function approach, together with response surface methodology (RSM) has been used to optimize medium composition, and the optimal medium was obtained via the desirability as follows: yeast extract 10.33 g/L, sucrose 27.24 g/L, KH2PO4 5.60 g/L and the optimal culture conditions are initial pH 6, 25°C, rotation speed 150 r/minute, inoculum size 4%(v/v), and medium capacity 40 mL/250 mL. Under these conditions, the yield of mycelia, intracellular polysaccharide, adenosine and mannitol reached 12.19 g/L, 0.6 g/L, 61.84 mg/L, and 1.38 g/L, respectively, and the D value was 0.77. Furthermore, the polysaccharides showed significant antitumor activities against HeLa and HepG2 in vitro in a dose-dependent manner in 72 hours. At a concentration of 1000 mg/mL, the inhibition rate of polysaccharides was 92.38% and 98.79%. The IC50 for HeLa and HepG2 were 70.91 μg/mL and 97.63 μg/mL, respectively.
It is well-known that deficiency or over exposure to various elements has noticeable effects on human health. The effect of an element is determined by several characteristics, including absorption, metabolism, and degree of interaction with physiological processes. Iron is an essential element for almost all living organisms as it participates in a wide variety of metabolic processes, including oxygen transport, deoxyribonucleic acid (DNA) synthesis, and electron transport. However, as iron can form free radicals, its concentration in body tissues must be tightly regulated because in excessive amounts, it can lead to tissue damage. Disorders of iron metabolism are among the most common diseases of humans and encompass a broad spectrum of diseases with diverse clinical manifestations, ranging from anemia to iron overload, and possibly to neurodegenerative diseases. In this review, we discuss the latest progress in studies of iron metabolism and bioavailability, and our current understanding of human iron requirement and consequences and causes of iron deficiency. Finally, we discuss strategies for prevention of iron deficiency.
Oxalate crystals and other types of crystals are the cause of urolithiasis, and these are related to oxidative stress. The search for new compounds with antioxidant qualities and inhibitors of these crystal formations is therefore necessary. In this study, we extracted four sulfated polysaccharides, a fucoglucoxyloglucuronan (DJ-0.3v), a heterofucan (DJ-0.4v), and two glucans (DJ-0.5v and DJ-1.2v), from the marine alga Dictyopteris justii. The presence of sulfated polysaccharides was confirmed by chemical analysis and FT-IR. All the sulfated polysaccharides presented antioxidant activity under different conditions in some of the in vitro tests and inhibited the formation of calcium oxalate crystals. Fucan DJ-0.4v was the polysaccharide that showed the best antioxidant activity and was one of the best inhibitors of the crystallization of calcium oxalate. Glucan DJ-0.5v was the second most potent inhibitor of the formation of oxalate crystals, as it stabilized dehydrated oxalate crystals (less aggressive form), preventing them from transforming into monohydrate crystals (more aggressive form). The obtained data lead us to propose that these sulfated polysaccharides are promising agents for use in the treatment of urolithiasis.
Many types of nanoparticles (NPs) are tested for use in medical products, particularly in imaging and gene and drug delivery. For these applications, cellular uptake is usually a prerequisite and is governed in addition to size by surface characteristics such as hydrophobicity and charge. Although positive charge appears to improve the efficacy of imaging, gene transfer, and drug delivery, a higher cytotoxicity of such constructs has been reported. This review summarizes findings on the role of surface charge on cytotoxicity in general, action on specific cellular targets, modes of toxic action, cellular uptake, and intracellular localization of NPs. Effects of serum and intercell type differences are addressed. Cationic NPs cause more pronounced disruption of plasma-membrane integrity, stronger mitochondrial and lysosomal damage, and a higher number of autophagosomes than anionic NPs. In general, nonphagocytic cells ingest cationic NPs to a higher extent, but charge density and hydrophobicity are equally important; phagocytic cells preferentially take up anionic NPs. Cells do not use different uptake routes for cationic and anionic NPs, but high uptake rates are usually linked to greater biological effects. The different uptake preferences of phagocytic and nonphagocytic cells for cationic and anionic NPs may influence the efficacy and selectivity of NPs for drug delivery and imaging.
J. Inst. Brew. 115(2), 151–158, 2009 Much research has been carried out over the years examining cell wall glucans from Saccharomyces cerevisiae and this study further examines aspects of the binding of (1→4)-α-D-glucan in the yeast cell wall, using a number of isolation techniques as well as monoclonal antibodies able to recognize a mixed (1→4)-α-D-glucan/(1→6)-β-D-glucan. Extraction of purified glucan, from S. cerevisiae cell wall, with 0.1N HCl, at 80°C for 6 h, released into the solution (1→4)-α-D-glucan and (1→6)-β-D-glucan as the major polysaccharides, along with an insoluble pellet highly enriched in (1→3)-β-D-glucan. The released (1→4)-α-D-glucan was composed of a high molecular size >100 kDa fraction (7.2% w/w) and a medium 5–50 kDa polysac-charide (10.2% w/w), with the (1→4)-α-D-glucan covalently bound to the (1→6)-β-D-glucan. The average molar ratio of the α:β glucan was 47: 53 in this mixed polysaccharide. The struc-ture of this polysaccharide was different from the structure of plant starch or animal glycogen as monoclonal antibodies spe-cific to yeast (1→4)-α-D-glucan/(1→6)-β-D-glucan did not recognize the plant starch or animal glycogen standards. Abbreviations: BSA – Bovine Serum Albumin; D 2 O – deute-rium oxide (heavy water), d.w. – dry weight; DI – deionised water; GEM – Glucan Enriched Material, HRP – Horse Radish Peroxidase.
Infant nutrition may influence eating behaviour and food preferences in later life. The present study explores whether exclusive breast-feeding duration and age at introduction of solid foods are associated with children's eating behaviour and fruit and vegetable intake at age 5 years. Data were derived from the Amsterdam Born Children and their Development study, a prospective birth cohort in the Netherlands, and included 3624 children. During infancy, data on infant nutrition were collected. Child eating behaviour (satiety responsiveness, enjoyment of food, slowness in eating and food responsiveness) was assessed with the Children's Eating Behaviour Questionnaire; and fruit and vegetable intake was calculated from a validated child FFQ. Both questionnaires were filled in by the mothers after their child turned 5 years. Exclusive breast-feeding duration was not associated with later eating behaviour, although longer exclusive breast-feeding was significantly associated with a higher vegetable intake at age 5 years. Compared with the introduction of solid foods at age 6 months, introduction before the age of 4 months was associated with less satiety responsiveness at age 5 years (β - 0·09; 95 % CI - 0·16, - 0·02). Introducing solid foods after 6 months was associated with less enjoyment of food (β - 0·07; 95 % CI - 0·12, - 0·01) and food responsiveness (β - 0·04; 95 % CI - 0·07, - 0·01). Introducing solid foods before the age of 4 months was associated with a higher fruit intake compared with introduction at 6 months. These findings suggest that prolonged breast-feeding and introduction of solid foods between 4 and 6 months may lead to healthier eating behaviour and food preferences at age 5 years.
Xylan is one of most abundant polymer after cellulose. However, its potential has yet to be completely recognized. Corn cobs contain a considerable reservoir of xylan. The aim of this work was to study some of the biological activities of xylan obtained from corn cobs after alkaline extraction enhanced by ultrasonication. Physical chemistry and infrared analyses showed 130 kDa heteroxylan containing mainly xylose:arabinose: galactose:glucose (5.0:1.5:2.0:1.2). Xylan obtained exhibited total antioxidant activity corresponding to 48.5 mg of ascorbic acid equivalent/g of xylan. Furthermore, xylan displayed high ferric chelating activity (70%) at 2 mg/mL. Xylan also showed anticoagulant activity in aPTT test. In antimicrobial assay, the polysaccharide significantly inhibited bacterial growth of Klebsiella pneumoniae. In a test with normal and tumor human cells, after 72 h, only HeLa tumor cell proliferation was inhibited (p < 0.05) in a dose-dependent manner by xylan, reaching saturation at around 2 mg/mL, whereas 3T3 normal cell proliferation was not affected. The results suggest that it has potential clinical applications as antioxidant, anticoagulant, antimicrobial and antiproliferative compounds.
Superparamagnetic iron oxide (SPIO, Ferumoxides, Feridex), an important MRI intravenous contrast reagent, is efficiently recognized and eliminated by macrophages in the liver, spleen, lymph nodes and atherosclerotic lesions. The receptors that recognize nanoparticles are poorly defined and understood. Since SPIO is coated with bacterial polysaccharide dextran, it is important to know whether carbohydrate recognition plays a role in nanoparticle uptake by macrophages. Lectin-like receptors CD206 (macrophage mannose receptor) and SIGNR1 were previously shown to mediate uptake of bacterial polysaccharides. We transiently expressed receptors MGL-1, SIGNR-1 and msDectin-1 in non-macrophage 293T cells using lipofection. The expression was confirmed by reverse transcription PCR. Following incubation with the nanoparticles, the uptake in receptor-expressing cells was not statistically different compared to control cells (GFP-transfected). At the same time, expression of scavenger receptor SR-A1 increased the uptake of nanoparticles three-fold compared to GFP-transfected and control vector-transfected cells. Blocking CD206 with anti-CD206 antibody or with the ligand mannan did not affect SPIO uptake by J774.A1 macrophages. Similarly, there was no inhibition of the uptake by anti-CD11b (Mac-1 integrin) antibody. Polyanionic scavenger receptor ligands heparin, polyinosinic acid, fucoidan and dextran sulfate decreased the uptake of SPIO by J774A.1 macrophages and Kupffer cells by 60-75%. These data unambiguously show that SPIO is taken up via interaction by scavenger receptors, but not via dextran recognition by carbohydrate receptors. Understanding of nanoparticle-receptor interaction can provide guidance for the design of long circulating, non-toxic nanomedicines.
Polysaccharides represent the major part of the yeast cell wall dry weight and build the skeletal carcass defining cell wall stability and cell morphology (beta-D-glucans) or constitute amorphous matrix and cell surface fibrous material (mannans and mannoproteins). It is known that yeast cell wall beta-D-glucans reveal immunomodulating properties, which allows for their application in anti-infective and antitumor therapy. Recent data also suggest that polysaccharides reveal antioxidant activity that can result in their protective function as antioxidants, antimutagens, and antigenotoxic agents. The paper provides a review of our continuing research involving water-soluble derivatives of beta-D-glucan isolated from the baker's yeast Saccharomyces serevisiae and of a glucomannan isolated from the industrial yeast Candida utilis. The results are confronted with the available literature data. The derivatives of beta-D-glucan demonstrated potent inhibitory effect on lipid peroxidation comparable to that of the known antioxidants and exerted DNA protection from oxidative damage. The free radical scavenging activity was confirmed by spin-trap electron paramagnetic resonance. Antimutagenic and antigenotoxic activity of the yeast polysaccharides was demonstrated using yeast, bacterial, and algal models. The derivatives of beta-D-glucan exerted potent enhancement of tumor necrosis factor alpha (TNF-alpha) released from murine macrophages and revealed synergistic effect with cyclophosphamide in the treatment of Lewis lung carcinoma and two types of lymphosarcoma in murine models. The results indicate significant protective antioxidant, antimutagenic, and antigenotoxic activities of the yeast polysaccharides and imply their potential application in anticancer prevention/therapy.
A spectrophotometric method has been developed for the quantitative determination of antioxidant capacity. The assay is based on the reduction of Mo(VI) to Mo(V) by the sample analyte and the subsequent formation of a green phosphate/Mo(V) complex at acidic pH. The method has been optimized and characterized with respect to linearity interval, repetitivity and reproducibility, and molar absorption coefficients for the quantitation of several antioxidants, including vitamin E. The phosphomolybdenum method, in combination with hexane monophasic extraction, has also been adapted for the specific determination of vitamin E in seeds. The results obtained with the proposed method were validated by comparison with a standard HPLC method. The phosphomolybdenum method is routinely applied in our laboratory to evaluate the total antioxidant capacity of plant extracts and to determine vitamin E in a variety of grains and seeds, including corn and soybean.
Copper (Cu) and its alloys are used extensively in domestic and industrial applications. Cu is also an essential element in mammalian nutrition. Since both copper deficiency and copper excess produce adverse health effects, the dose-response curve is U-shaped, although the precise form has not yet been well characterized. Many animal and human studies were conducted on copper to provide a rich database from which data suitable for modeling the dose-response relationship for copper may be extracted. Possible dose-response modeling strategies are considered in this review, including those based on the benchmark dose and categorical regression. The usefulness of biologically based dose-response modeling techniques in understanding copper toxicity was difficult to assess at this time since the mechanisms underlying copper-induced toxicity have yet to be fully elucidated. A dose-response modeling strategy for copper toxicity was proposed associated with both deficiency and excess. This modeling strategy was applied to multiple studies of copper-induced toxicity, standardized with respect to severity of adverse health outcomes and selected on the basis of criteria reflecting the quality and relevance of individual studies. The use of a comprehensive database on copper-induced toxicity is essential for dose-response modeling since there is insufficient information in any single study to adequately characterize copper dose-response relationships. The dose-response modeling strategy envisioned here is designed to determine whether the existing toxicity data for copper excess or deficiency may be effectively utilized in defining the limits of the homeostatic range in humans and other species. By considering alternative techniques for determining a point of departure and low-dose extrapolation (including categorical regression, the benchmark dose, and identification of observed no-effect levels) this strategy will identify which techniques are most suitable for this purpose. This analysis also serves to identify areas in which additional data are needed to better define the characteristics of dose-response relationships for copper-induced toxicity in relation to excess or deficiency.
Mushrooms are regarded as one of the well-known foods and biopharmaceutical materials with a great deal of interest. Polysaccharide beta-glucan is the major component of mushrooms that displays various biological activities such as antidiabetic, anticancer, and antihyperlipidemic effects. In this study, we compared the immunostimulatory potency of polysaccharide fractions, prepared from liquid culture of pinemushroom Tricholoma matsutake, with a potent immunogen lipopolysaccharide (LPS), and their molecular mechanisms on the functional activation of macrophages. We found that fraction II (TMF-II) was able to comparably upregulate or highly enhance the phenotypic functions of macrophages such NO production and cytokine (IL-1beta, IL-6, IL-12, and TNF-alpha) expression, to LPS. TMF-II triggered the phosphorylation of IkappaBalpha, a critical step for NF-kappaB activation and translocation. Of the upstream signaling enzymes tested, Src and Akt were thought to be the responsible upstream signaling components in induction of NO production, although TMF-II strongly upregulated the phosphorylation of all MAPK pathways. Therefore, our data suggest that T. matsutake-derived beta-glucan may exert its immunostimulating activities with similar potency to LPS via activation of multiple signaling pathways linked to NF-kappaB activation.
Strains belonging to the yeast species Kluyveromyces marxianus have been isolated from a great variety of habitats, which results in a high metabolic diversity and a substantial degree of intraspecific polymorphism. As a consequence, several different biotechnological applications have been investigated with this yeast: production of enzymes (beta-galactosidase, beta-glucosidase, inulinase, and polygalacturonases, among others), of single-cell protein, of aroma compounds, and of ethanol (including high-temperature and simultaneous saccharification-fermentation processes); reduction of lactose content in food products; production of bioingredients from cheese-whey; bioremediation; as an anticholesterolemic agent; and as a host for heterologous protein production. Compared to its congener and model organism, Kluyveromyces lactis, the accumulated knowledge on K. marxianus is much smaller and spread over a number of different strains. Although there is no publicly available genome sequence for this species, 20% of the CBS 712 strain genome was randomly sequenced (Llorente et al. in FEBS Lett 487:71-75, 2000). In spite of these facts, K. marxianus can envisage a great biotechnological future because of some of its qualities, such as a broad substrate spectrum, thermotolerance, high growth rates, and less tendency to ferment when exposed to sugar excess, when compared to K. lactis. To increase our knowledge on the biology of this species and to enable the potential applications to be converted into industrial practice, a more systematic approach, including the careful choice of (a) reference strain(s) by the scientific community, would certainly be of great value.
Cell wall polysaccharides from filamentous fungi and yeasts have been reported as antioxidant and antiproliferative polymers. Thus, we evaluated these activities from cell wall polysaccharides from Kluyveromyces marxianus CCT7735. By using a centrifugal filter, a 203 kDa α-D-mannan (KMM-5) was obtained. KMM-5 exhibited no effect on HeLa cells and a weak antiproliferative activity against Hep-G2 cells. In addition, at higher concentrations, it presented a cytotoxicity to the normal cell line, 3T3. However, KMM-5 showed copper- and iron-chelating abilities, the latter of which presented improved activity. By using 2D-NMR COSY, HSQC edited and HMBC experiments, a structure arrangement was proposed. The main chain was formed by 6)-α-D-Manp-(1 → 6) units substituted at the 2-O-position by non-reducing terminals α-D-Manp-(1 → 2) and by a branched tetrasaccharide. The latter was formed by an internal 2)-α-D-Manp-(1 → 2) unit with linked to it a 2,3)-α-D-Manp-(1 → 2) unit substituted at the 2-O-position by a non-reducing terminal α-D-Manp-(1 → 2), and at the 3-O-position by a non-reducing terminal α-D-Manp-(1 → 3). In conclusion, we considered K. marxianus CCT7735 a source of natural and renewable polysaccharides with pharmacological properties.
Two polysaccharides from Ganoderma lucidum (GLP1 from fermentation broth and GLP2 from fruiting body) were obtained and investigated for their in vitro antioxidant properties. The two polysaccharides showed strong antioxidant activities in a dose-dependent manner. At 5.0 mg/mL, the reducing power and the scavenging rate on DPPH radical and hydroxyl radical of GLP1 were 1.25, 50 and 80%, while that of GLP2 were 1.46, 85, and 78%, respectively. GLP1 and GLP2 also showed strong protective effects on yeast cells from UV and H2O2 damage. At 20 mg/mL, the protective effects on yeast cells from UV and H2O2 of GLP1 were 57 and 49%, and that of GLP2 were 84 and 79%, respectively. Thus, both GLP1 and GLP2 could be considered as antioxidants for food and pharmaceutical industries.
Polysaccharides (PSs) and sulfated polysaccharides (SPSs) were isolated from sodium sulfate-, and potassium sulfate-feeding mycelia of Antrodia cinnamomea and their chemical components and molecular weight distribution were studied. The highest value of SPS content in the SPSs was 1.22 mmol/g SPSs for sodium sulfate 1 mM feeding for 49 days. SPSs of A. cinnamomea contained five fractions. The area percentage of low-molecular-weight SPSs (<20 kDa) covered almost half of the SPSs mixture. Glucose was the major sugar in the SPS mixture. To study the effects of SPSs on anti-inflammation activity, an in vitro assay was performed on lipopolysaccharide (LPS)-stimulated inflammation in RAW264.7 macrophages. SPSs showed a stronger inhibitory effect on tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release compared to those of non-sulfated polysaccharide (PS), with both at values of 100% suppression. This fact suggests that the sulfation degree of SPS may play a role in anti-inflammatory activity.
This chapter focuses on Kluyveromyces genus and its member species. Asexual reproduction in this genus occurs through multilateral budding on a narrow base. The cells are ovoidal, ellipsoidal, cylindrical to elongate and pseudomycelium may be formed, although true hyphae are not produced. The ascospores are smooth, reniform, bacilliform, ellipsoidal, or spheroidal, which tend to agglutinate after liberation. Glucose is fermented vigorously and nitrate is not assimilated. The member species of this genus include Kluyveromyces aestuarii, Kluyveromyces africanus, Kluyveromyces bacillisporus, Kluyveromyces blattae, Kluyveromyces delphensis, and Kluyveromyces dobzhanskii. One to four spheroidal to ellipsoidal ascospores with central refringent globules are formed in Kluyveromyces aestuarii. Conjugation between cells of the same culture or between bud and parent-cell usually precedes ascus formation. In case of Kluyveromyces africanus, asci arise directly from diploid cells. One to 16 or more oblong or reniform ascospores are formed and the spores are liberated from the ascus soon after formation and tend to agglutinate. Asci are formed on YM or malt extract agar after 2–5 days at 17–25° C, but mature ascospores are rarely observed.
β-Glucans, homopolymers of glucose, are widespread in many microorganisms, mushrooms and plants. They have attracted attention because of their bioactive and medicinal functions. One important source of β-glucans is the cell wall of yeasts, especially that of baker’s yeast Saccharomyces cerevisiae. Several processes for the isolation of β-glucans, using alkali, acid or a combination of both, result in degradation of the polymeric chains. In this paper, we have an enzymatic process for the isolation of glucans from yeast cell walls. As a result, β-glucans were obtained in a yield of 18.0% of the original ratio in the yeast cell walls. Therefore, this isolation process gave a better yield and higher β-glucan content than did traditional isolation methods. Furthermore, results showed that each extraction step of β-glucan had a significant effects on its chemical properties.
The interest in the role of ferrous iron in diabetes pathophysiology has been revived by recent evidence of iron as an important determinant of pancreatic islet inflammation and as a biomarker of diabetes risk and mortality. The iron metabolism in the β-cell is complex. Excess free iron is toxic, but at the same time iron is required for normal β-cell function and thereby glucose homeostasis. In the pathogenesis of diabetes, iron generates reactive oxygen species (ROS) by participating in the Fenton chemistry, which can induce oxidative damage and apoptosis. The aim of this review is to present and discuss recent evidence suggesting that iron is a key pathogenic factor in both type 1 and type 2 diabetes with a focus on inflammatory pathways. Pro-inflammatory cytokine-induced β-cell death is not fully understood, but may include iron induced ROS formation resulting in de-differentiation by activation of transcription factors, activation of the mitochondrial apoptotic machinery or of other cell-death mechanisms. The pro-inflammatory cytokine IL-1β facilitates divalent metal transporter 1 (DMT1) induced β-cell iron-uptake and consequently ROS-formation and apoptosis, and we propose that this mechanism provides the relay between inflammation and oxidative β-cell damage. Iron chelation may be a potential therapeutic approach to reduce disease severity and mortality among diabetes patients. However, the therapeutic effect and safety of iron reduction needs to be tested in clinical trials before dietary interventions of the use of titrated iron chelation therapy to avoid anaemia. This article is protected by copyright. All rights reserved.
Genes in which germline mutations confer highly or moderately increased risks of cancer are called cancer predisposition genes. More than 100 of these genes have been identified, providing important scientific insights in many areas, particularly the mechanisms of cancer causation. Moreover, clinical utilization of cancer predisposition genes has had a substantial impact on diagnosis, optimized management and prevention of cancer. The recent transformative advances in DNA sequencing hold the promise of many more cancer predisposition gene discoveries, and greater and broader clinical applications. However, there is also considerable potential for incorrect inferences and inappropriate clinical applications. Realizing the promise of cancer predisposition genes for science and medicine will thus require careful navigation.
The transition metal iron is essential for life, yet potentially toxic iron-catalyzed reactive oxygen species (ROS) are unavoidable in an oxygen-rich environment. Iron and ROS are increasingly recognized as important initiators and mediators of cell death in a variety of organisms and pathological situations. Here, we review recent discoveries regarding the mechanism by which iron and ROS participate in cell death. We describe the different roles of iron in triggering cell death, targets of iron-dependent ROS that mediate cell death and a new form of iron-dependent cell death termed ferroptosis. Recent advances in understanding the role of iron and ROS in cell death offer unexpected surprises and suggest new therapeutic avenues to treat cancer, organ damage and degenerative disease.
Three water-soluble polysaccharide fractions (IOP40, IOP60 and IOP80) were isolated by using different concentrations of alcohol precipitation from Inonotus obliquus sclerotia. Their physicochemical properties, including total sugar content, protein content, monosaccharide composition and percentage were analyzed. And their in vitro antioxidant capacities were investigated in terms of reducing power assay and scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, hydroxyl radicals, superoxide anion radicals and hydrogen peroxide (H2O2). In general, three polysaccharide fractions exhibited increasing antioxidant activity with increasing concentration at the ranges of tested dosage. The orders of reducing power, DPPH-scavenging capacity, H2O2-scavenging capacity, and hydroxyl-scavenging activity were all IOP60>IOP40>IOP80. These findings demonstrated that three polysaccharide fractions extracted from I. obliquus, especially IOP60, could be employed as natural ingredients in functional food and pharmaceutical industry to alleviate the oxidative stress.
Microbial and plant polysaccharides in nature are frequently exposed to oxidative burst. They may act as antioxidants buffering the radical attack. This paper presents antioxidant properties of prepared yeast mannans, commercial β-glucans as well as the chemically prepared carboxymethylated β-glucan (CM-glucan). The hydroxyl radical antioxidant assay and the DPPH radical-scavenging assay were used. Yeast mannans and β-glucans (1.6mg.mL(-1)) showed antioxidant capacities against OH up to 14.1%, while CM-glucan was significantly higher antioxidant (65.4%). In the DPPH assay, the antioxidant capacities of yeast mannans and β-glucans (1.0mg.mL(-1)) were lower and reached up to ∼ 6.5%. All polysaccharides tested were effectively degraded by OH and the presence of salicylate considerably inhibited their degradation. Measure of Fe (2+) chelation revealed less than 13.1% effectivity for all polysaccharides. In all antioxidant and degradation experiments the yeast mannans showed very similar results to commercial β-glucans. The antioxidant capacities of polysaccharides may be assessed by simple HPLC monitoring.
Most real-world networks from various fields share a universal topological property as community structure. In this paper, we propose a node-similarity based mechanism to explore the formation of modular networks by applying the concept of hidden metric spaces of complex networks. It is demonstrated that network community structure could be formed according to node similarity in the underlying hidden metric space. To clarify this, we generate a set of observed networks using a typical kind of hidden metric space model. By detecting and analyzing corresponding communities both in the observed network and the hidden space, we show that the values of the fitness are rather close, and the assignments of nodes for these two kinds of community structures detected based on the fitness parameter are extremely matching ones. Furthermore, our research also shows that networks with strong clustering tend to display prominent community structures with large values of network modularity and fitness. A unique mechanism based on the hidden metric spaces to explore the origin of network community structure. Hidden edge-clustering coefficient reflecting the similarity of the corresponding two nodes. Detecting hidden communities of nodes in the hidden metric space. Great homologies of modularity in hidden metric spaces and networks suggest a nice explanation for the formation of communities.
Yeasts have a long tradition of application in biotechnology and a more recent history of use as research models for biochemistry, metabolism, genetics and cell biology. Without doubt, Saccharomyces cerevisiae has been the dominant representative in all these aspects. There is tremendous diversity among yeasts, however, and the application of modern microbiological and molecular approaches has resulted in renewed focus on the biology and industrial potential of other yeasts. The dairy yeast Kluyveromyces marxianus is of particular interest in this regard because of traits that render it especially suitable for industrial application. These include the fastest growth rate of any eukaryotic microbe, thermotolerance, the capacity to assimilate a wide range of sugars, secretion of lytic enzymes, and the production of ethanol by fermentation. Despite the importance of these traits, and significant exploitation by the biotechnology sector, fundamental research with K. marxianus is just emerging from the shadow of its sister species, Kluyveromyces lactis. The availability of new molecular tools and resources for K. marxianus, its interesting metabolic and cellular traits, and the potential to become the leading yeast for many biotechnological processes, argue strongly for increased research into this particular species.
An extracellular polysaccharide (PN) composed of mannose:3-O-methyl-galactose:galactose:glucose (44.9:16.3:19.8:19) was obtained from Pleurotus sajor-caju. This polymer showed specific antioxidant activities such as total antioxidant capacity, superoxide radical scavenging, reducing power and ferric chelating, but it did not possess anticoagulant or antiproliferative activities. Through chemical modification of PN, the hydroxyl radical scavenging and reducing power activities of PN increased. A derived sulfated polysaccharide of PN, with a DS of 0.17 and named PS, was obtained using a sulfuric acid/n-propanol method. The sulfation was confirmed by electrophoresis, NMR and FT-IR. In addition, PS prolonged the time of coagulation in a concentration-dependent manner in aPTT test. The antiproliferative effect against HeLa cells was time dependent; after 72h, the inhibition rate of PS (1.0mg/mL) was approximately 60%. PS demonstrated promising antioxidant, antiproliferative and anticoagulant properties and has been selected for further studies.
In order to investigate the effect of lactose concentration and oxygen level on the growth and metabolism of Kluyveromyces marxianus UFV-3 in cheese whey permeate, batch cultures were conducted under aerobic, hypoxic, and anoxic conditions, with lactose at initial concentration ranging from 1 to 240 g L−1. The increase in lactose concentration increased ethanol yield and ethanol volumetric productivity, and has reduced cell yield. When lactose concentration was equal or above 50 g L−1 and the oxygen levels were low, the ethanol yield was close to its theoretical value. Maximum ethanol concentrations attained in this study were 76 and 80 g L−1 in hipoxia and anoxia, respectively. The lactose consumption rate in anoxia was greater than in aerobiosis and hipoxia. However, under anoxia, the lactose consumption rate of K. marxianus followed a saturation kinetics, which was not observed in hypoxia and aerobiosis. All oxygen levels investigated, showed a tendency for saturation of the ethanol production rate above 65 g L−1 lactose. Ethanol production rate was also higher on anoxia.
The production, preliminary characterization and antitumor activity in vitro of mycelial polysaccharides from Pholiota dinghuensis Bi (PDP) were investigated in the present study. Firstly, crude PDP was prepared from the mycelia of P. dinghuensis Bi by submerged culture. Then, the crude PDP was purified by chromatography of DEAE-52 cellulose and Sephadex G-100, resulting three purified fractions of PDP-1, PDP-2 and PDP-3. We found that the monosaccharide composition of PDP-3 was greatly different from that of PDP-1 or PDP-2. In addition, it contained the highest contents of protein, sulfate and uronic acid among the polysaccharides tested. Furthermore, PDP-3 exhibited higher antiproliferative activity against human gastric cancer BGC-823 cells in vitro than crude PDP, PDP-1 or PDP-2. At a concentration of 400 mg/L and an exposure time of 72 h, the inhibition rates for crude PDP, PDP-2 and PDP-3 were 69.36%, 73.65% and 85.78%, respectively.
A new heteropolysaccharide, named as SIP, was isolated from the ink of cuttlefish, Sepiella maindroni, by enzymolysis, anion-exchange and gel-permeation chromatography and tested for its antimutagenic activity. It was homogeneous with a molecular weight of 1.13×10(4)Da by HPSEC-MALLS analysis. SIP contained glucuronic acid, mannose, N-acetylgalactosamine, and fucose in a molar ratio of 1:1:2:2. Its structural characteristics were investigated and elucidated by methylation analysis, GLC-MS, and NMR ((1)H, (13)C, H-H COSY, HMQC, HMBC, TOCSY and NOESY). The hexasaccharide repeating unit of SIP was found to be a backbone composed of fucose, N-acetylgalactosamine and mannose in a molar ratio of 2:2:1, and with a single branch of glucuronic acid at the C-3 position of mannose. According to the micronucleus test, SIP could significantly reduce the frequency of micronucleated cells in polychromatic erythrocytes and reticulocytes induced by cyclophosphamide in tumor-bearing mice, which revealed that SIP presented strong antimutagenic activity.
Copyright © 2008 Elsevier Ltd. All rights reserved.
Eleven edible leafy vegetables of India have been analysed for their free radical-scavenging activity in different systems of assay, e.g. DPPH radical-scavenging activity, superoxide radical-scavenging activity in riboflavin/light/NBT system, hydroxyl radical-scavenging activity, and inhibition of lipid peroxidation induced by FeSO4 in egg yolk. Total antioxidant activity was measured, based on the reduction of Mo(VI) to Mo(V) by the extract and subsequent formation of green phosphate/Mo(V) complex at acid pH. The extracts were found to have different levels of antioxidant properties in the systems tested. Considering all the activities, it can be said that Ipomoea reptans has good activity amongst the eleven plant materials screened for their antioxidant properties. Lowest activity was found in Nyctanthes arbortristis. Many flavonoids and related polyphenols contribute significantly to the total antioxidant activity of many fruits and vegetables. However, there was no correlation between antioxidant activity and total phenol/flavonoid content.
The antioxidant properties of two wild edible mushroom species from the northeast of Portugal, Lactarius deliciosus (L.) Gray and Tricholoma portentosum (Fr.) Quél., were evaluated. Methanolic extracts from the entire mushroom, the cap and the stipe, separately, were screened for their reducing power and free radical scavenging capacity by chemical assays. The total phenolic content was determined, in order to assess its effect on the extract’s antioxidant activity. Both two species showed antioxidant potential; but L. deliciosus proved to be more active. The portion of the mushroom used had an influence on the results obtained, with the cap methanolic extracts exhibiting the greatest antioxidant effect.
Simple sugars, oligosaccharides, polysaccharides, and their derivatives, including the methyl ethers with free or potentially free reducing groups, give an orange-yellow color when treated with phenol and concentrated sulfuric acid. The reaction is sensitive and the color is stable. By use of this phenol-sulfuric acid reaction, a method has been developed to determine submicro amounts of sugars and related substances. In conjunction with paper partition chromatography the method is useful for the determination of the composition of polysaccharides and their methyl derivatives.
The cardiomyopathies are heart muscle diseases of primary or secondary origin. Primary cardiomyopathies are often of unknown cause, hence their treatment is limited to general heart failure management. In secondary cardiomyopathies, in contrast, the identification of the underlying cause allows for a more specific, hence effective, approach that, when applied early, may prevent the development of heart failure.
The term iron overload cardiomyopathy (IOC) recently has been introduced to describe a secondary form of cardiomyopathy resulting from the accumulation of iron in the myocardium mainly because of genetically determined disorders of iron metabolism or multiple transfusions.1,2 This condition, although previously overlooked, has lately attracted the attention of investigators because iron overload is, on one hand, a frequently encountered condition, especially in association with certain hematologic conditions, and on the other hand, its accurate identification and effective management have now become possible.
IOC has been recently described as a dilated cardiomyopathy, characterized by left ventricular (LV) remodeling with chamber dilatation and reduced LV ejection fraction (LVEF).1 However, primary hemochromatosis, a genetically determined condition leading to iron overload, is classically categorized as an infiltrative cause of restrictive cardiomyopathy.3 Moreover, secondary hemochromatosis may lead to severe diastolic LV dysfunction in the early stages of the disease, before LVEF is affected.4,5 In the present review, we describe the forms, pathophysiology, and phenotypic expression of IOC, focusing on ventricular geometry and function and describing the early diastolic abnormalities that lead ultimately to heart muscle dysfunction and heart failure. The clinical implications of the condition are also discussed.
Iron overload is the accumulation of excess body iron in different organs as a result of increased intestinal absorption, parenteral administration, or increased dietary intake.6 Besides being a crucial component of hemoglobin with a key role in erythropoiesis, oxygen …
The activation of macrophages for antimicrobial responses is a multistage event involving numerous intracellular signalling cascades that makes possible target cell destruction by these effector cells. This study examined the effects of different potassium channel inhibitors and activators on the NO production of murine macrophage-like cell lines P388D.1 and B10-4(S). We found that the potassium channel inhibitors tetraethylammonium, 4-aminopyridine, and quinine caused dose-dependent reductions in the NO production of macrophages, and that the potassium channel activator, minoxidol, caused a dose-dependent enhancement of NO production. The inhibition of NO production was due to involvement of potassium channels in the priming stage of macrophage activation, since pretreatment with the priming agent interferon-gamma partially restored the NO response of the macrophages. The results of this study demonstrate a link between potassium channel activity and the activation of anitimicrobial functions of murine macrophages.
the multifunctional potential of neferine derived from the embryo of Nelumbo nucifera seeds for the age-related neurodegenerative disorders, in vivo anti-amnesic activities and in vitro cholinesterases (ChEs)- and β-site APP cleaving enzyme 1 (BACE1)-inhibitory activities, as well as anti-inflammatory and antioxidant activities were investigated.
in vivo anti-amnesic activities were performed via the passive avoidance, Y-maze, and Morris water maze tasks in a scopolamine-induced amnesia model. The cell-free antioxidant capacities were evaluated by in vitro scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radicals, and peroxynitrite (ONOO(-)), as well as inhibitory activities against nitric oxide (NO), superoxide anion (O(2)(-)), lipid peroxidation, and ONOO(-)-mediated tyrosine nitration. The intracellular antioxidant capacities were also determined via inhibitory activities of lipopolysaccharide (LPS)-induced NO generation and NF-κB activation in RAW 264.7 cells.
neferine showed significant improvement in cognitive impairment in scopolamine-induced amnesia animal models and moderate inhibitory activities in ChEs and BACE1 assays. In addition, it exhibited notable scavenging activities against DPPH, ABTS, NO, and O(2)(-) radicals, as well as ONOO(-). Neferine also demonstrated remarkable inhibitory activity against lipid peroxidation and protein nitration in cell-free antioxidant assays and moderate inhibitory activity of NO generation with exceptional suppression of NF-κB activation in cell-based assays.
the results demonstrate that the anti-amnesic effect of neferine may be mediated via antioxidant and anti-inflammatory capacities, as well as inhibition of ChEs and BACE1.
Two low-molecular-weight polysaccharides, GLP(L)1 and GLP(L)2, purified from a crude Ganoderma lucidum polysaccharide preparation GLPP were investigated for their physicochemical properties, structure characterization and antioxidant activities. The results indicated that GLP(L)1 was a glucan with an average molecular weight of 5.2kDa, while GLP(L)2 was composed of glucose, galactose and mannose in a ratio of 29:1.8:1.0 with the average molecular weight of 15.4kDa. GLP(L)1 and GLP(L)2 had similar structure characteristic which contained linkages such as -->3)-Glcp-(1-->, -->4)-Glcp-(1-->, -->6)-Glcp-(1-->, -->3,6)-Glcp-(1-->, and -->4,6)-Glcp-(1--> in the percentage ratio of 21.9:20.3:23.7:24.0:3.7 and 23.0:34.6:7.0:14.1:3.0 in the backbone or branches, respectively. Antioxidant results showed that both GLP(L)1 and GLP(L)2 exhibited antioxidant activities while GLP(L)1 was more effective in free radicals scavenging and Fe(2+) chelating. Low-molecular-weight polysaccharide seems to play an important role in the exploration of natural antioxidants in food industry and pharmaceuticals.
Sulfated polysaccharides from 11 species of tropical marine algae (one edible specie of Rhodophyta, six species of Phaeophyta and four species of Chlorophyta) collected from Natal city coast (Northeast of Brazil) were evaluated for their anticoagulant, antioxidant and antiproliverative in vitro activities. In the activated partial thromboplastin time (APTT) test, which evaluates the intrinsic coagulation pathway, seven seaweeds presented anticoagulant activity. Dictyota cervicornis showed the highest activity, prolonging the coagulation time to double the baseline value in the APTT with only 0.01 mg/100 microl of plasma, 1.4-fold lesser than Clexane, a low molecular weight heparin. In the protrombin time (PT) test, which evaluates the extrinsic coagulation pathway, only Caulerpa cupresoides showed anticoagulant activity. All species collected showed antioxidant activities. This screening emphasized the great antioxidant potential (total capacity antioxidant, power reducing and ferrous chelating) of four species: C. sertularioide; Dictyota cervicornis; Sargassum filipendula and Dictyopteris delicatula. After 72 h incubation, HeLa cell proliferation was inhibited (p<0.05) between 33.0 and 67.5% by S. filipendula; 31.4 and 65.7% by D. delicatula; 36.3 and 58.4% by Caulerpa prolifera and 40.2 and 61.0% by Dictyota menstrualis at 0.01-2mg/mL algal polysaccharides. The antiproliferative efficacy of these algal polysaccharides were positively correlated with the sulfate content (r=0.934). Several polysaccharides demonstrated promising antioxidant, antiproliferative an/or anticoagulant potential and have been selected for further studies on bioguided fractionation, isolation and characterization of pure polysaccharides from these species as well as in vivo experiments are needed and are already in progress.
Leukocytes respond to lipopolysaccharide (LPS) at nanogram per milliliter concentrations with secretion of cytokines such as tumor necrosis factor-alpha (TNF-alpha). Excess secretion of TNF-alpha causes endotoxic shock, an often fatal complication of infection. LPS in the bloodstream rapidly binds to the serum protein, lipopolysaccharide binding protein (LBP), and cellular responses to physiological levels of LPS are dependent on LBP. CD14, a differentiation antigen of monocytes, was found to bind complexes of LPS and LBP, and blockade of CD14 with monoclonal antibodies prevented synthesis of TNF-alpha by whole blood incubated with LPS. Thus, LPS may induce responses by interacting with a soluble binding protein in serum that then binds the cell surface protein CD14.
Nitro blue tetrazolium has been used to intercept O2− generated enzymically or photochemically. The reduction of NBT by O2− has been utilized as the basis of assays for superoxide dismutase, which exposes its presence by inhibiting the reduction of NBT. Superoxide dismutase could thus be assayed either in crude extracts or in purified protein fractions. The assays described are sensitive to ng/ml levels of super-oxide dismutase and were applicable in free solution or on polyacrylamide gels. The staining procedure for localizing superoxide dismutase on polyacrylamide electrophoretograms has been applied to extracts obtained from a variety of sources. E. coli has been found to contain two superoxide dismutases whereas bovine heart, brain, lung, and erthrocytes contain only one.
A tetrazolium salt has been used to develop a quantitative colorimetric assay for mammalian cell survival and proliferation. The assay detects living, but not dead cells and the signal generated is dependent on the degree of activation of the cells. This method can therefore be used to measure cytotoxicity, proliferation or activation. The results can be read on a multiwell scanning spectrophotometer (ELISA reader) and show a high degree of precision. No washing steps are used in the assay. The main advantages of the colorimetric assay are its rapidity and precision, and the lack of any radioisotope. We have used the assay to measure proliferative lymphokines, mitogen stimulations and complement-mediated lysis.
Bacterial lipopolysaccharide (LPS) has been recognized as one of the most potent activating signals for mouse peritoneal macrophages. In macrophages primed by interferon-gamma (IFN-gamma) or trehalose dimycolate (TDM), LPS induces NO synthase and the events associated with a high nitric oxide output: antitumor and antiparasitic activities. In the present report, it is shown that drugs (calcium ionophores or thapsigargin) which elevate the concentration of cytosolic calcium, [Ca2+]i, induce NO synthase and antitumor activities in primed macrophages, mimicking LPS action. Calcium ionophores and thapsigargin trigger NO synthase activity in macrophages primed in vivo by TDM, in thioglycollate-elicited macrophages primed in vitro by IFN-gamma, and in IFN-gamma-treated EMT6 adenocarcinoma cells. However, activation of TDM-primed macrophages by LPS does not seem to involve calcium fluxes: (i) no change in [Ca2+]i was detectable in TDM-primed macrophages loaded with Fura-2 and exposed to LPS, and (ii) activation of TDM-primed macrophages by LPS can be obtained in the presence of 4 mM EGTA. NO synthase expression is thus controlled in primed macrophages by two different pathways; calcium ionophores can replace LPS but do not act through the same intracellular cascade.
Cell walls, representing 26%-32% of the cell dry weight, were prepared from several strains of the yeasts Kloeckera apiculata, Debaryomyces hansenii, Zygosaccharomyces bailii, Kluyveromyces marxianus and Saccharomyces cerevisiae. Extraction of the walls with potassium hydroxide at 4 degrees C, followed by saturation of the alkali-soluble extract with ammonium sulphate gave fractions of mannoprotein, alkali-soluble glucan and alkali-insoluble glucan. Chitin was associated with the alkali-insoluble glucan. The proportions of the different fractions within the walls varied with the species and strain. Mannoprotein comprised between 25% and 34% of the walls, the content of alkali-insoluble glucan ranged from 15% to 48%, and the content of alkali-soluble glucan ranged from 10% to 48%. There was significant variation in the physical appearance of the alkali-soluble glucans and the relative viscosity of suspensions of these glucans. The yeasts could represent novel sources of polysaccharides with industrial and medical applications.
On many occasions, baker’s yeast (Saccharomyces cerevisiae) has been referred to as the Escherichia coli of the eukaryotic world. Yeast has been extensively characterized genetically and a complete physical map is now available.
Much of the comparison to E. coli is based on the observations that culturing yeast is simple, economical, and rapid, with a doubling time in rich medium of
approx 90 min. Cells divide mitotically by forming a bud, which is subsequently pinched off to form a daughter cell. Yeast
can also be grown on a completely defined medium, which has allowed the isolation of numerous nutritional auxotrophs. This
type of analysis has provided manly mutations useful for genetic analysis and as selectable markers for plasmid manipulation.
The carbohydrate polymers known as beta-1,3-d-glucans exert potent effects on the immune system - stimulating antitumour and antimicrobial activity, for example - by binding to receptors on macrophages and other white blood cells and activating them. Although beta-glucans are known to bind to receptors, such as complement receptor 3 (ref. 1), there is evidence that another beta-glucan receptor is present on macrophages. Here we identify this unknown receptor as dectin-1 (ref. 2), a finding that provides new insights into the innate immune recognition of beta-glucans.
Mannoprotein with emulsification properties was extracted from the cell walls of Kluyveromyces marxianus grown on a lactose-based medium by autoclaving cells in a citrate buffer at pH 7. The purified product was evaluated for chemical and physical stability to establish its potential use as a natural emulsifier in processed foods. The yield of purified bioemulsifier from this strain of K. marxianus was 4-7% of the original dry cell weight. The purified product, at a concentration of 12 g l(-1), formed emulsions that were stable for 3 months when subjected to a range of pH (3-11) and NaCl concentrations (2-50 g l(-1)). The composition of this mannoprotein was 90% carbohydrate (mannan) and 4-6% protein. These values are similar to mannoprotein extracted from cells of Saccharomyces cerevisiae, which is the traditional source. Consequently K. marxianus cultivated on a low-cost lactose-based medium such as whey, a lactose-rich clean waste of the dairy industry, could be developed as a source of bioemulsifier for use in the food industry.
The antioxidant potency of different molecular weight (DMW) chitosan and sulfated chitosan derivatives was investigated employing various established in vitro systems, such as superoxide (O(2)(.-))/hydroxyl ((-.)OH) radicals scavenging, reducing power, iron ion chelating. As expected, we obtained several satisfying results, as follows: firstly, low molecular weight chitosan had stronger scavenging effect on O(2)(.-) and (-.)OH than high molecular weight chitosan. For example the O(2)(.-) scavenging activity of low molecular weight chitosan (9 kDa) and high molecular weight chitosan (760 kDa) were 85.86% and 35.50% at 1.6 mg/mL, respectively. Secondly, comparing with DMW chitosan, DMW sulfated chitosans had the stronger inhibition effect on O(2)(.-). At 0.05 mg/mL, the scavenging activity on O(2)(.-) reached 86.26% for low molecular weight chitosan sulfate (9 kDa), but that of low molecular weight chitosan (9 kDa) was 85.86% at 1.6 mg/mL. As concerning chitosan and sulfated chitosan of the same molecular weight, scavenging activities of sulfated chitosan on superoxide and hydroxyl radicals were more pronounced than that of chitosan. Thirdly, low molecular weight chitosan sulfate had more effective scavenging activity on O(2)(.-) and (-.)OH than that of high molecular weight chitosan sulfate. Fourthly, DMW chitosans and sulfated chitosans were efficient in the reducing power, especially LCTS. Their orders were found to be LCTS>CTS4>HCTS>CTS3>CTS2>CTS1>CTS. Fifthly, CTS4 showed more considerable ferrous ion-chelating potency than others. Finally, the scavenging rate and reducing power of DMW chitosan and sulfated derivatives increased with their increasing concentration. Moreover, change of DMW sulfated chitosans was the most pronounced within the experimental concentration. However, chelating effect of DMW chitosans were not concentration dependent except for CTS4 and CTS1.
The treatment of Wilson's disease has changed considerably in recent times, from the use of penicillamine (Cuprimine, Merck) for all stages and types of disease, to the use of three other anticopper drugs at appropriate times for appropriate patients. Each type and stage of the disease can be considered as a therapeutic target, for which specialised therapy is appropriate. This paper systematically reviews the various types and stages of Wilson's disease presentation, and provides opinion on the appropriate therapy for each. For patients presenting with neurological disease, the use of tetrathiomolybdate is optimum; for patients presenting with mild-to-moderate hepatic failure, a combination of trientine (Syprine, Merck) and zinc is recommended, whereas liver transplantation is necessary for those with severe failure; zinc therapy alone or trientine alone as second choice is recommended for patients presenting with hepatitis or cirrhosis without liver failure, for maintenance therapy, for treatment of presymptomatic patients and for treatment of paediatric and pregnant patients.
Hepcidin is a peptide hormone secreted by the liver that plays a central role in the regulation of iron homeostasis. Increased hepcidin levels result in anemia while decreased expression is the causative feature in most primary iron overload diseases. Mutations in hemochromatosis type 2 (HFE2), which encodes the protein hemojuvelin (HJV), result in the absence of hepcidin and an early-onset form of iron overload disease. HJV is a bone morphogenetic protein (BMP) coreceptor and HJV mutants have impaired BMP signaling. In this issue of the JCI, Babitt and colleagues show that BMPs are autocrine hormones that induce hepcidin expression (see the related article beginning on page 1933). Administration of a recombinant, soluble form of HJV decreased hepcidin expression and increased serum iron levels by mobilizing iron from splenic stores. These results demonstrate that recombinant HJV may be a useful therapeutic agent for treatment of the anemia of chronic disease, a disorder resulting from high levels of hepcidin expression.