ArticleLiterature Review

Konjac Glucomannan, a Promising Polysaccharide of Amorphophallus konjac K. Koch in Health Care:

Authors:
  • Centre for Food Biology & Environment Studies
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

In recent year, konjac glucomannan (KGM) has attracted more attention due to its non-harmful and non-toxic properties, good biocompatibility, biodegradability and hydrophilic ability. Moreover, KGM and their derivatives have several importances in the multidirectional research areas such as nutritional, biotechnological and fine chemical fields. In the previous article, we have reviewed the nutritional aspects of KGM covering the various aspects of functional foods, food additives and their derivatives. This review aims at highlighting the diverse biomedical research conducted on KGM in the past ten years, covering therapies for anti-obesity, regulation in lipid metabolism, laxative effect, anti-diabetic, anti-inflammatory, prebiotic to wound dressing applications. Moreover, this review deals with global health aspects of KGM and the disparate health related factors associated with diseases and their control measures.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Konjac glucomannan (KGM) is a rich source of soluble fiber that contains almost no calories [1]. Because KGM has good biocompatibility and biodegradability, it is widely used globally as a medicinal supplement, and is also used as a traditional food in Japan in the form of konjac jelly, noodles, and tofu [1][2][3][4][5][6][7]. KGM has a significant role in the treatment and prevention of various diseases because of its pleiotropic effects, including anti-diabetic, anti-obesity, anti-inflammatory, prebiotic, antibiotic, immune regulatory, and laxative activities. ...
... KGM has a significant role in the treatment and prevention of various diseases because of its pleiotropic effects, including anti-diabetic, anti-obesity, anti-inflammatory, prebiotic, antibiotic, immune regulatory, and laxative activities. Previous studies have shown that KGM offers major health benefits-such as lowering blood glucose, cholesterol, triglyceride (TG), lowering blood pressure levels, and reducing body weight by promoting intestinal activity and boosting immune function in humans [1][2][3][4][5][6][7]. In these investigations, participants habitually ingested KGM every day for 8 weeks [1][2][3][4][5][6][7]. ...
... Previous studies have shown that KGM offers major health benefits-such as lowering blood glucose, cholesterol, triglyceride (TG), lowering blood pressure levels, and reducing body weight by promoting intestinal activity and boosting immune function in humans [1][2][3][4][5][6][7]. In these investigations, participants habitually ingested KGM every day for 8 weeks [1][2][3][4][5][6][7]. KGM absorbs digested body waste in the stomach and intestines by entrapping it within a gelatinous mass, which is eliminated from the body without being absorbed. ...
Article
Full-text available
In a recent study, we showed that konjac glucomannan (KGM) inhibits rice gruel-induced postprandial increases in plasma glucose and insulin levels. To extend this research, we investigated the effects of KGM addition to rice gruel on pre- and postprandial concentrations of circulating lipoprotein lipase (LPL), glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), hepatic triglyceride lipase (HTGL), free fatty acids (FFA), and triglycerides (TG). A total of 13 Japanese men, without diabetes, dyslipidemia, or gastrointestinal diseases, interchangeably ingested rice gruel containing no KGM (0%G), rice gruel supplemented with 0.4% KGM (0.4%G), and rice gruel supplemented with 0.8% KGM (0.8%G), every Sunday for 3 weeks. Blood samples were obtained at baseline and at 30, 60, and 120 min after ingestion to measure the abovementioned lipid parameters. Lipid parameters showed small, but significant, changes. Significant reductions were found in circulating FFA levels among all participants. Circulating TG levels significantly declined at 30 min and then remained nearly constant in the 0.8%G group but exhibited no significant difference in the 0%G and 0.4%G groups. Although circulating levels of LPL and GPIHBP1 significantly decreased in the 0%G and 0.4%G groups, they increased at 120 min in the 0.8%G group. Participants in the 0%G and 0.4%G groups showed significant decreases in circulating HTGL levels, which was not observed in the 0.8%G group. Our results demonstrate the novel pleiotropic effects of KGM. Supplementation of rice gruel with KGM powder led to TG reduction accompanied by LPL and GPIHBP1 elevation and HTGL stabilization, thereby attenuating TG metabolism.
... Tra i meccanismi d'azione riconosciuti efficaci relativi all'assunzione di fibre solubili si riconoscono il prolungamento del tempo di svuotamento gastrico, un aumento del senso di sazietà e un aumento dell'escrezione fecale di colesterolo e sali biliari 107 . Le prove disponibili dimostrano costantemente un effetto di riduzione del colesterolo totale e del colesterolo LDL del β-glucano, una fibra viscosa di avena e orzo. ...
... L'assunzione di psillio, inoltre, ha effetti positivi su metabolismo del glucosio ed insulino-resistenza 111 ; -glucomannano: contrariamente ad altre fibre, il glucomannano non si lega agli acidi biliari, ma sembra ridurre l'assorbimento di colesterolo a livello del digiuno e l'assorbimento degli acidi biliari nell'ileo, portando al miglioramento dei livelli circolanti di apolipoproteina B e colesterolo LDL. Aumenta anche l'attività della 7-α-idrossilasi, un enzima che converte il colesterolo in acidi biliari 107 . Una recente metanalisi comprendente 14 trial clinici randomizzati che hanno arruolato 531 pazienti ha concluso che l'uso del glucomannano riduce significativamente colesterolemia LDL e trigliceridemia (rispettivamente in media di 16 e 12 mg/dl) 112 . ...
... Tra i meccanismi d'azione riconosciuti efficaci relativi all'assunzione di fibre solubili si riconoscono il prolungamento del tempo di svuotamento gastrico, un aumento del senso di sazietà e un aumento dell'escrezione fecale di colesterolo e sali biliari 107 . Le prove disponibili dimostrano costantemente un effetto di riduzione del colesterolo totale e del colesterolo LDL del β-glucano, una fibra viscosa di avena e orzo. ...
... L'assunzione di psillio, inoltre, ha effetti positivi su metabolismo del glucosio ed insulino-resistenza 111 ; -glucomannano: contrariamente ad altre fibre, il glucomannano non si lega agli acidi biliari, ma sembra ridurre l'assorbimento di colesterolo a livello del digiuno e l'assorbimento degli acidi biliari nell'ileo, portando al miglioramento dei livelli circolanti di apolipoproteina B e colesterolo LDL. Aumenta anche l'attività della 7-α-idrossilasi, un enzima che converte il colesterolo in acidi biliari 107 . Una recente metanalisi comprendente 14 trial clinici randomizzati che hanno arruolato 531 pazienti ha concluso che l'uso del glucomannano riduce significativamente colesterolemia LDL e trigliceridemia (rispettivamente in media di 16 e 12 mg/dl) 112 . ...
Article
Full-text available
Cardiovascular prevention represents one of the most important strategies of public health, since cardiovascular diseases are the first cause of morbidity and mortality worldwide. Measures to promote a healthy lifestyle and an adequate control of risk factors need be highlighted also during the COVID-19 outbreak, which has dramatically changed the priorities and the use of available resources by the National Health Systems. Indeed, the COVID-19 pandemic and the consequent lockdown measures imposed in several countries have caused a widespread diffusion of behaviors with detrimental effects on the cardiovascular system, including inappropriate dietary habits, sedentary lifestyle and smoking. Moreover, as a consequence of the COVID-19 outbreak, a relevant number of programmed follow-up visits and screening procedures have been cancelled, and hospital admissions for severe acute pathologies, such as myocardial infarction, have been significantly reduced, with a parallel increase in fatality and complication rates. This represents a serious social issue, whose impact will last for many years, and which deserves priority attention by the scientific and healthcare communities. In such a context, cardiovascular prevention may play a key role in interrupting this vicious circle. The aim of this update of the 2018 SIPREC consensus document is to analyze and highlight the available evidence produced by medical research over the last 3 years, providing with the synergistic contribution of many scientific societies an integrated tool to support clinical practice. Indeed, important new recommendations have been introduced in the management of hypertension, dyslipidemias and type 2 diabetes, consisting in the identification of lower therapeutic targets, the promotion of combination strategies and the introduction in routine clinical practice of new effective pharmacological classes, such as sodium-glucose cotransporter-2 inhibitors for the treatment of diabetes and heart failure and proprotein convertase subtilisin/kexin type 9 inhibitors for hypercholesterolemia. Moreover, new evidence has become available for the management of antiplatelet therapy, both in primary and secondary prevention. Finally, much attention has been devoted to telemedicine, which has shown great promise to support cardiovascular prevention and care not only during the COVID-19 pandemic but also as part of routine care in the future.
... Glucomannan is a soluble fiber derived from Amorphophallus konjac (konjac root) [25]. Unlike other fibers, glucomannan does not act by binding bile acids, but it seems to reduce the absorption of cholesterol in the jejunum and the absorption of bile acids in the ileum. ...
... Unlike other fibers, glucomannan does not act by binding bile acids, but it seems to reduce the absorption of cholesterol in the jejunum and the absorption of bile acids in the ileum. Moreover, it increases the activity of 7-α-hydroxylase converting cholesterol into bile acids [25]. ...
Article
Full-text available
Purpose of Review The aim of this review is to summarize the available clinical efficacy and safety data related to the most studied and used lipid-lowering nutraceuticals. Recent Findings A growing number of meta-analyses of randomized clinical trials supports the effectiveness and tolerability of some lipid-lowering nutraceuticals such as red yeast rice, plant sterols and stanols, soluble fibers, berberine, artichoke extracts, bergamot polyphenol fraction, garlic, green tea, and spiruline. No significant safety concern has been raised for the use of such products. Association of more lipid-lowering nutraceuticals and of some nutraceuticals with lipid-lowering drugs has been tested as well. Summary Current evidence suggests that some clinically tested lipid-lowering nutraceuticals could be safely used to improve plasma lipid levels in subjects affected by mild-to-moderate dyslipidaemia with low cardiovascular risk.
... As expected, the percentage of mannose was higher than that of glucose, without significant differences between the original polymer and the processed samples. The molar ratio determined for the commercial KGM was 1.6, the same as described by several authors (Behera and Ray, 2016;Tang et al., 2018). However, the hydrolysis of the polymer slightly increased the relative amount of mannose measured as a small shift of the molar ratio from 1.6 to 1.7. ...
... KGM has a swelling capacity in water (Behera and Ray, 2016), thus, a degree of swelling was expected upon contact with aqueous fluids. Unloaded KGM microparticles were incubated in PBS and SLF and the evolution of their size and shape was compared with the dry powder. ...
Article
Few medically-approved excipients are available for formulation strategies to endow microcarriers with improved performance in lung drug targeting. Konjac glucomannan (KGM) is a novel, biocompatible material, comprising mannose units potentially inducing macrophage uptake for the treatment of macrophage-mediated diseases. This work investigated spray-dried KGM microparticles as inhalable carriers of model antitubercular drugs, isoniazid (INH) and rifabutin (RFB). The polymer was characterised and different polymer/drug ratios tested in the production of microparticles for which respirability was assessed in vitro. The swelling of KGM microparticles and release of drugs in simulated lung fluid were characterised and the biodegradability in presence of β-mannosidase, a lung hydrolase, determined. KGM microparticles were drug loaded with 66% - 91% association efficiency and had aerodynamic diameter around 3 µm, which enables deep lung penetration. The microparticles swelled upon liquid contact by 40% - 50% but underwent size reduction (> 62% in 90 min) in presence of β-mannosidase, indicating biodegradability. Finally, drug release was tested showing slower release of RFB compared with INH but complete release of both within 24 h. This work identifies KGM as a biodegradable polymer of natural origin that can be engineered to encapsulate and release drugs in respirable microparticles with physical and chemical macrophage-targeting properties.
... In the native KGM, acetyl groups prevent their gelation; however, its de-esterification results in the thermally stable gels Time required to achieve full hydration and viscosity is decreased with increase in the temperature and degree of shear KGM form gels at a pH range of 9-10, and these are stable at a temperature of 200°C and above Exhibit synergistic properties with K-carageenan, XG, LBG, starch and modified starches Meat, surimi, burger, soy analogs, noodles, gels Prebiotic, laxative, anti-inflammatory, anti-obesity, anti-diabetic properties, regulates lipid metabolism, detoxification, phelgum liquefaction, tumor-suppression and blood stasis alleviation [21] (Continued) [23] (Continued) Bakery products, confectionary products, pastries, whipped toppings, reduced fat ice-creams, yoghurts and infant formulas Rich in essential amino acids, anti-catabolic, antioxidant, antidiabetic, antihypertensive, antitumor. [24,25] Xanthan gum (XG) INS number: 415 CAS number:11,138-66-2 Soluble in both hot and cold water Requires intensive agitation when exposed to an aqueous medium to avoid the formation of lumps ...
... Being soluble, plant gums can act as prebiotics, help in the regulation of lipid metabolism, cholesterol reduction and possess laxative, anti-inflammatory, antiobesity and anti-diabetic properties. [21] ...
Article
Stabilizers are used to enhance the textural properties and shelf-life of the foods without altering their nutritional properties. The availability of a wide array of stabilizers makes the selection of suitable stabilizers a tedious job. The purpose of this review is to provide a comprehensive picture of the extraction/production, chemistry, techno-functional properties, stability, safety and food and therapeutic applications of natural, microbial and modified stabilizers. The cost and safety aspects have also been discussed. This review also appraises and provides insights on the potential suitability of different stabilizers in diverse food sectors viz., bakery, dairy, meat and fruit and vegetables.
... Acidity of colonic environment influences for manipulating microbial composition selectively by lowering pH of colonic content in the human colon resulted in suppression of harmful bacteria i.e., pathogens which affect to human health (Scott et al., 2012). The health properties of glucomannan have been investigated as having prebiotic potential, with applications in health foods and pharmaceuticals (Behera & Ray, 2016) by inhibiting pathogens, stimulating immunity, reducing blood lipid levels, reducing insulin resistance, influencing brain function, providing energy and mineral bioavailability (Gibson et al., 2017). SCFA production to provide energy for epithelial cells and improve the colon health (Donohoe et al., 2011). ...
Article
Full-text available
Abstract Porang glucomannan is a polysaccharide extracted from Amorphophallus oncophylus and its degradation product is porang oligo-glucomannan (POG). It contains glucomannan, which has been used as an emulsifier, thickener, or as a nutritional supplement to counter many diseases. While it is believed to have health benefits, there are only limited studies exploring this aspect of porang glucomannnan (PGM). It was hydrolyzed using β-mannanase to obtain POG under optimal conditions: reaction temperature of 37 °C, reaction time of 4 h, pH 5.5 and E/S of 1:1,000 (w/w). The study aimed to evaluate the fermented POG, which might also generate short-chain fatty acids (SCFA) and to estimate the prebiotic activity score of POG fermented in vitro. The results show that SCFA profiles of POG fermentation gave a high acetic acid concentration (32.64 mM) and butyric acid (6.68 mM) at 12 h, having butyrogenic effects after a rapid fermentation. Mostly the beneficial bacteria grew faster on POG and KOG (konjac oligo-glucomannan) than on PGM or control at the beginning of incubation. Among the substrates screened, POG showed a highly positive prebiotic index of 10.29, increasing bifidobacteria and lactobacilli but reducing bacteroides population. So, POG is a candidate prebiotic since it has bifidogenic, butyrogenicity, and fermentability.
... Cultivated Amorphophallus spp. are crucial economic crops for the food, chemical and pharmaceutical industries that can accumulate large amounts of glucomannan (KGM) [1]. However, many diseases have negative effects on Amorphophallus spp. ...
Article
Amorphophallus spp. are important industrial crops in Southwest China. Unfortunately, bacterial disease is one of the factors limiting the development of the Amorphophallus spp. industry. Soft rot can be caused by the pathogen Pectobacterium carotovorum subsp. carotovorum (Pcc) and leads to large-scale losses in Amorphophallus spp. quality and production. However, the mechanisms underlying the response of Amorphophallus spp. to Pcc remain largely unknown. This study compared two species of Amorphophallus, A. muelleri and A. konjac, to explore Pcc resistance by combined physiological and transcriptome analysis. On the basis of phenotype analysis, A. muelleri exhibited higher resistance to Pcc than A. konjac. Moreover, the transcriptomes of A. muelleri and A. konjac were assembled, and differentially expressed genes (DEGs) were annotated. Significant categories including the plant hormone transduction pathway, phenylpropanoid biosynthesis pathway and plant pathogen interaction pathway were identified. Among these pathways, small auxin upregulated RNA (SAUR), ethylene responsive transcription factor 1 (ERF1), 4-coumarate-CoA ligase (4CL), peroxidase (POD), WRKY transcription factor, Ca2+ sensor-related and mitogen-activated protein kinase (MAPK) genes were upregulated in A. muelleri, which may be involved in the regulation of energy, oxidative stress and signal transduction upon exposure to Pcc infection. The transcription levels of four selected genes were further verified by quantitative real-time PCR. Overall, this study identifies several critical genes involved in resistance to soft rot disease in Amorphophallus spp. and provides a theoretical foundation for identifying potential targets for metabolic engineering for disease control.
... Konjac mannan oligosaccharides (KMOS) are important functional oligosaccharides, which are the hydrolytic products of konjac glucomannan, isolated from tubers of Amorphophallus konjac K. Koch (14). Konjac mannan oligosaccharide (KMOS) is a hydrolysis product of konjac glucomannan, consisting of b-Dmannose and b-D-glucose residues linked together by b-(1!4) glycosidic bonds. ...
Article
Full-text available
As the first line of defense against intestinal bacteria and toxins, intestinal epithelial cells are always exposed to bacteria or lipopolysaccharide (LPS), whereas pathogenic bacteria or LPS can cause intestinal epithelial cell damage. Previous studies have shown that konjac mannan oligosaccharides (KMOS) have a positive effect on maintaining intestinal integrity, and Bacillus subtilis (BS) can promote the barrier effect of the intestine. However, it is still unknown whether KMOS and BS have a synergistic protective effect on the intestines. In this study, we used the LPS-induced Caco-2 cell injury model and mouse intestinal injury model to study the synergistic effects of KMOS and BS. Compared with KMOS or BS alone, co-treatment with KMOS and BS significantly enhanced the activity and antioxidant capacity of Caco-2 cell, protected mouse liver and ileum from LPS-induced oxidative damage, and repaired tight junction and mucus barrier damage by up-regulating the expression of Claudin-1, ZO-1 and MUC-2. Our results demonstrate that the combination of KMOS and BS has a synergistic repair effect on inflammatory and oxidative damage of Caco-2 cells and aIIeviates LPS-induced acute intestinal injury in mice.
... Among them, Amorphophallus konjac has been cultivated and used as a food source and medicinal herb in China as early as 206 BCE in Shen Nong's Herbal Classic. 4 It was promptly introduced by monks to Korea in 550 and then to Japan and rapidly became a commodity in the planting program in 19th century. 5 A. konjac and Amorphophallus albus are commonly planted and consumed varieties for commercial KGM sources, which dominate the konjac market. ...
... Konjac (A. konjac), a perennial plant belonging to the family Araceae, is widely grown as a cash crop in tropical and subtropical Asian countries such as China, India, and Japan. The konjac glucomannan (KGM), extracted from the corm, is a water-soluble polysaccharide (dietary fiber) with diverse applications in food science and nutrition, biotechnology, pharmacology and fine chemicals (Behera and Ray, 2016;Zhu, 2018). However, bacterial sot rot is becoming a major threat to konjac production in China (Wu et al., 2015). ...
Article
Full-text available
Bacterial soft rot is a devastating disease for a wide range of crops, vegetables, and ornamental plants including konjac (Amorphophallus konjac). However, the pangenome and genomic plasticity of the konjac soft rot pathogens is little explored. In this study, we reported the complete genome sequences of 11 bacterial isolates that can cause typical soft rot symptoms in konjac by in vitro and in vivo pathogenicity tests. Based on in silico DNA–DNA hybridization, average nucleotide identity and phylogenomic analysis, all 11 isolates were determined to be Pectobacterium aroidearum. In addition, synteny analysis of these genomes revealed considerable chromosomal inversions, one of which is triggered by homologous recombination of ribose operon. Pangenome analysis and COG enrichment analysis showed that the pangenome of P. aroidearum is open and that accessory genes are enriched in replication, recombination, and repair. Variations in type IV secretion system and type VI secretion system were found, while plant cell wall degrading enzymes were conserved. Furthermore, sequence analyses also provided evidence for the presence of a type V secretion system in Pectobacterium. These findings advance our understanding of the pathogenicity determinants, genomic plasticity, and evolution of P. aroidearum.
... In seeds of fenugreek and guar, the endosperm is nonliving and the cells are almost totally filled with galactomannans [21], and in the seeds of Ceratonia siliqua, galactomannans are observed as thickenings in the walls of living endosperm [22]. Among mannans, glucomannans are of particular importance, and many reviews have covered the properties, applications and health benefits of various glucomannans from different sources [23][24][25][26]. Xyloglucans are found in the primary cell walls and the cotyledons of some dicotyledonous seeds, where they function as storage polysaccharides. ...
Article
Full-text available
Carbohydrates are the major storage reserves in seeds, and they are produced and accumulated in specific tissues during the growth and development of a plant. The storage products are hydrolyzed into a mobile form, and they are then translocated to the developing tissue following seed germination, thereby ensuring new plant formation and seedling vigor. The utilization of seed reserves is an important characteristic of seed quality. This review focuses on the seed storage reserve composition, source–sink relations and partitioning of the major transported carbohydrate form, i.e., sucrose, into different reserves through sucrolytic processes, biosynthetic pathways, interchanging levels during mobilization and crosstalk based on vital biochemical pathways that interlink the carbon and nitrogen cycles. Seed storage reserves are important due to their nutritional value; therefore, novel approaches to augmenting the targeted storage reserve are also discussed.
... Sebagian besar penyandang obesitas mengonsumsi lebih banyak makanan selingan jika dibandingkan dengan orang yang memiliki status gizi normal. Selain jumlah porsi yang kandungan asam lemak rantai pendek di saluran pencernaan; d) meningkatkan ekologi kolon pada orang dewasa yang sehat (9,10). Glukomanan dikonsumsi bukan dalam bentuk tepung, tetapi merupakan komposisi suatu produk. ...
Article
Full-text available
Effect of jelly containing of porang (Amorphophalus oncophyllus) glucomannan and inulin as a snack to the body weight, BMI, body fat, total cholesterol, and triglyceride levels in obese adult Background: Obesity is a major risk factor for noncommunicable diseases, especially cardiovascular disease. Porang glucomannan and inulin are water-soluble fibers that have been widely studied for their health benefits. Jelly products that contain both types of fiber are expected to have the ability to support the diet program in adults with obese nutritional status. Objective: To determine the effect of giving jelly containing a combination of glucomannan porang and inulin on body weight, BMI, body fat, total cholesterol, and triglyceride levels in obese adults. Methods: This research is a randomized controlled trial using a pre and post-test design. A total of 55 subjects who live in the Special Region of Yogyakarta, participated in the study until the end of 8 weeks. Subjects were divided into 3 groups; 18 people in the group who were given jelly containing glucomannan porang and inulin (porang-inulin jelly group), 17 people in the group who were given placebo jelly (placebo jelly group), and 20 people in the negative control group who did not get jelly (negative control group). All subjects received a low-calorie diet intervention of 1,500 kcal in the first month and 1,200 kcal in the second month. Results: There was a significant reduction in body weight and BMI (p0.05). Clinically, there was a significant decrease in body fat percentage in the porang-inulin jelly group, in subjects with the category of an excess fat percent (-0.90 ± 0.49%) and obesity (-1.48 ± 0.83%). A significant decrease in fat percentage also occurred in the porang-inulin jelly group, both in male subjects (-1.42 ± 0.50%) and female (-1.15 ± 0.82%), while in the placebo jelly group and negative control, the decrease did not occur in all categories and genders. There was an increase in total cholesterol levels in the negative control group (p
... At the same time, the three carbohydrate components (trehalose, mannan and glucomannan) belong to complex sugars. Glucomannan is composed of glucose and mannose, whereas mannan is composed of 2 mannose molecules[8]. Trehalose is a disaccharide consisting of 2 glucose molecules[4]. In Arabidopsis, xylose, arabinose, glucose, galactose, mannose and other sugars were constituent components of hemicellulose, a mixture of polysaccharides in which the biomass was the most abundant after cellulose[23]. ...
... Konjac powder processed from the konjac tuber has been offered as a water-soluble dietary fiber supplement (Devaraj et al. 2019). It is considered one of the "top ten healthy foods" by the World Health Organization (Behera and Ray 2016). Owing to its water absorptivity, emulsifying, and thickening properties, konjac powder is also widely used as thickener and stabilizer to improve food quality. ...
Article
Full-text available
Partially hydrolyzed konjac powder (PHKP) can be used to increase the daily intake of dietary fibers of consumers. To produce PHKP by enzymatic hydrolysis, a novel β-mannanase gene (McMan5B) from Malbranchea cinnamomea was expressed in Pichia pastoris. It showed a low identity of less than 52% with other GH family 5 β-mannanases. Through high cell density fermentation, the highest β-mannanase activity of 42200 U mL⁻¹ was obtained. McMan5B showed the maximal activity at pH 7.5 and 75 °C, respectively. It exhibited excellent pH stability and thermostability. Due to the different residues (Phe214, Pro253, and His328) in catalytic groove and the change of β2-α2 loop, McMan5B showed unique hydrolysis property as compared to other β-mannanases. The enzyme was employed to hydrolyze konjac powder for controllable production of PHKP with a weight-average molecular weight of 22000 Da (average degree of polymerization 136). Furthermore, the influence of PHKP (1.0%−4.0%) on the qualities of steamed bread was evaluated. The steamed bread adding 3.0% PHKP had the maximum specific volume and the minimum hardness, which showed 11.0% increment and 25.4% decrement as compared to the control, respectively. Thus, a suitable β-mannanase for PHKP controllable production and a fiber supplement for steamed bread preparation were provided in this study. Key points • A novel β-mannanase gene (McMan5B) was cloned from Malbranchea cinnamomea and expressed in Pichia pastoris at high level. • McMan5B hydrolyzed konjac powder to yield partially hydrolyzed konjac powder (PHKP) instead of manno-oligosaccharides. • PHKP showed more positive effect on the quality of steamed bread than many other dietary fibers including konjac powder.
... Freeze drying is a low-temperature dehydration process that the gelled sol is frozen and then dried through the sublimation process under a high vacuum. Konjac glucomannan (KGM) is a neutral heteropolysaccharide, its main chain composed of d-glucose (G) and d-mannoses (M) in a molar ratio of 1:1.6 linked by β-(1,4)-glycosidic bond (Behera & Ray 2016). Starch ) is a polymeric carbohydrate consisting of glucose, which can be classified into two kinds depending on the structure, i.e., amylose and amylopectin. ...
Article
Full-text available
Biomass-based aerogel is a new promising environmentally friendly filter material to remove fine particle matter and minimize air pollution. This study aims to investigate the air filtration properties of biomass-based aerogels via tests in a transparent chamber and verification in a real room with a burning smudge stick as a the particle source. The biomass-based aerogel used in this study is made of polysaccharides, protein and waste agricultural by-product (wheat straw). The addition of wheat straw contributes to the increase of surface area and complexity of the biomass-based aerogel pore structure. Compared with other commonly used commercial filtration materials including high-efficiency particulate air (HEPA) filter, surgical mask, regular cloth and silica aerogel, biomass-based aerogel K0.9G1.8S3.6WS1.8 shows excellent performance to remove PM 2.5 (99.50%) and PM 10 (99.40%) from the environment. When using the biomass-based aerogel, the filter core sample has a smaller volume and simpler structure than HEPA to achieve the similar filtration performance. The filtration performance of the biomass-based aerogels has been verified with a real room test. The current work demonstrates the high potential of biomass-based aerogels for infiltration application in different fields and provides an avenue to reuse agricultural by-products.
... In this study, we embarked on a quest to efficiently produce tailor-made HM polysaccharides in yeast, by exploring how swapping the domains from two CSLA enzymes from konjac (a monocot) and Arabidopsis (a dicot) modulate its yield and composition. In the developing konjac corm [25], AkCSLA3 produces glucomannan that already has promising health care applications, including for the treatment of life style diseases [36]. While AtCSLA2 is most important for seed mucilage biosynthesis in Arabidopsis [9,19], novel links between seed HM structure and salt tolerance provide an indication that fine-tuning HM structure could also be relevant for engineering stress-resistant crops [37]. ...
Article
Full-text available
Background The carbohydrate polymers that encapsulate plants cells have benefited humans for centuries and have valuable biotechnological uses. In the past 5 years, exciting possibilities have emerged in the engineering of polysaccharide-based biomaterials. Despite impressive advances on bacterial cellulose-based hydrogels, comparatively little is known about how plant hemicelluloses can be reconstituted and modulated in cells suitable for biotechnological purposes. Results Here, we assembled cellulose synthase-like A (CSLA) enzymes using an optimized Pichia pastoris platform to produce tunable heteromannan (HM) polysaccharides in yeast. By swapping the domains of plant mannan and glucomannan synthases, we engineered chimeric CSLA proteins that made β-1,4-linked mannan in quantities surpassing those of the native enzymes while minimizing the burden on yeast growth. Prolonged expression of a glucomannan synthase from Amorphophallus konjac was toxic to yeast cells: reducing biomass accumulation and ultimately leading to compromised cell viability. However, an engineered glucomannan synthase as well as CSLA pure mannan synthases and a CSLC glucan synthase did not inhibit growth. Interestingly, Pichia cell size could be increased or decreased depending on the composition of the CSLA protein sequence. HM yield and glucose incorporation could be further increased by co-expressing chimeric CSLA proteins with a MANNAN-SYNTHESIS-RELATED (MSR) co-factor from Arabidopsis thaliana . Conclusion The results provide novel routes for the engineering of polysaccharide-based biomaterials that are needed for a sustainable bioeconomy. The characterization of chimeric cellulose synthase-like enzymes in yeast offers an exciting avenue to produce plant polysaccharides in a tunable manner. Furthermore, cells modified with non-toxic plant polysaccharides such as β-mannan offer a modular chassis to produce and encapsulate sensitive cargo such as therapeutic proteins. Graphic abstract
... KGM has high molecular weight (200-2000 KDa) and is an insoluble dietary fiber with high water levels absorbing up to 60-80 times its own weight [9]. However, the attribute 2 of 14 of high water absorption also makes KGM difficult to disperse in aqueous solutions [10]. ...
Article
Full-text available
This present work investigated the influence of konjac glucomannan (KGM) enzymatic hydrolysates on the textural properties, microstructure, and water distribution of surimi gel from grass carp (Ctenopharyngodon idellus). The molecular weight (Mw) of KGM enzymatic hydrolyzed by β-dextranase degraded from 149.03 kDa to 36.84 kDa with increasing enzymatic time. In the microstructure of surimi gels, KGM enzymatic hydrolysates with higher Mw showed entangled rigid-chains, while KGM enzymatic hydrolysates with lower Mw (36.84 kDa) exhibited swelled fragments. The hardness of surimi gel with a decline in KGM Mw exhibited first increasing then decreasing trends, while the whiteness of surimi gel increased. When KGM Mw decreased, the immobile water percentage of total signals decreased from 96.7% to 93.6%, and mobile water increased from 3.03% to 6.37%. In particular, the surimi gel with the addition of K2 showed better gel strength and water distributions. KGM enzymatic hydrolysates are expected to be used as a low-calorie healthy gel enhancer in surimi processing.
... Glucomannan is a neutral hetero-polysaccharide composed of D-glucose and D-mannose linked by -1,4 glycosidic bonds [39]. The primary source of glucomannan abroad is the konjac tuber and similar tubers that are widely grown in the plains of East Asia, such as China and Japan [40]- [42]. In addition, glucomannan can be obtained from schlep tubers [43] and porang tubers [44]- [46]. ...
... Glucomannan has been investigated for its effects on many obesity-related conditions [126]. The FDA has reviewed data on konjac glucomannan and its effect on blood lipids for determining a beneficial physiological effect and thus its ability to be labeled as a fiber [111]. ...
Article
Full-text available
Dietary supplements for weight management include myriad ingredients with thermogenic, lipotropic, satiety, and other metabolic effects. Recently, the safety of this product category has been questioned. In this review, we summarize the safety evidence as well as relevant clinical findings on weight management and metabolic effects of six representative dietary supplement ingredients: caffeine, green tea extract (GTE), green coffee bean extract (GCBE), choline, glucomannan, and capsaicinoids and capsinoids. Of these, caffeine, GTE (specifically epigallocatechin gallate [EGCG]), and choline have recommended intake limits, which appear not to be exceeded when used according to manufacturers’ instructions. Serious adverse events from supplements with these ingredients are rare and typically involve unusually high intakes. As with any dietary component, the potential for gastrointestinal intolerance, as well as possible interactions with concomitant medications/supplements exist, and the health status of the consumer should be considered when consuming these components. Most of the ingredients reviewed also improved markers of metabolic health, such as glucose, lipids, and blood pressure, although the data are limited for some. In summary, weight management supplements containing caffeine, GTE, GCBE, choline, glucomannan, and capsaicinoids and capsinoids are generally safe when taken as directed and demonstrate metabolic health benefits for overweight and obese people.
... Acetylation occurs randomly at the C-6 position of sugar unit with degree of acetylation from 1 per 9-20 sugar units. (Behera & Ray, 2016;Chua et al., 2010). Short side branches occur at the C-3 position of M residues or C-3 positions on both G and M in the main chain. ...
Article
A safe and cost effective approach to reduce obesity and accompanying chronic disease would be through controlling appetite and energy balance. Konjac glucomannan (KGM), a soluble dietary fiber (DF) that hydrates gradually and develops high viscosity in solution, has been demonstrated in some preclinical and clinical studies to reduce appetite and obesity. KGM has the highest hydrated volume at the lowest concentration of any DF. Therefore, oral KGM can instill a filling of fullness at a lower dose than other fiber supplements. Appetite reduction may be through increasing gastric retention and delaying gastric emptying by the “mass effect” of a gel-like viscous mass forming in the stomach that triggers afferent vagal signals of fullness. Absorption of nutrients in the lumen is slowed and beneficially increases the levels of appetite related hormones. The intake of KGM either as a supplement or in foods has been shown to have a weight loss effect. However, the results of randomized clinical trials have not been consistent. Besides differences in dose, study duration, and participant selection, the molecular structure and hydration properties of KGM are not described. This may be part of the explanation for the inconsistent results. The current review collected published information related to the role of KGM supplementation in regulation of appetite and obesity, focused on the association between micro and macro physicochemical structures of KGMs with their functions as appetite regulator. Collective clinical data of KGM on long-term metabolic energy surplus and weight loss were also provided.
... The smaller the amylose content or, the higher the amylopectin content, the material is stickier [19]. These were supported by the opinion of Behera and Ray [24], that the starch in tubers can be used for various types of food that require an elastic and sticky texture. ...
Article
Full-text available
To be consumed as healthy food, it is necessary to improve the process to reduce the calorie value of the wet noodles. For this reason, this study used taro flour to substitute wheat flour in the processing of wet noodles. However, the use of taro flour as raw material for making noodles will reduce the quality of the product, especially from the noodles’ elasticity and texture. For this purpose, konjac flour containing glucomannan was added. Therefore, it is necessary to study the processing of wet noodles with various proportions of taro and wheat flour, and konjac flour concentration on the quality of wet noodles. This research used two factors treatment namely: the ratio of taro and wheat flour with three levels (30%:70%, 40%:60%, and 50%:50%) and konjac flour concentration with three levels (1.5%, 3.0%, and 4.5%) based on total flour weight. The parameters observed in this study were the content of water, ash, protein, fat, carbohydrate, calorie value, and the organoleptic test, which included taste, colour, aroma, and texture. Based on the analysis of variants, there was no interaction between factors. Still, the factor of the proportion of taro and konjac flour indicated the significant difference between levels for all chemical parameters except fat. Besides, the Friedman test indicates the significant difference for all organoleptic parameters. The results showed that the best treatment was the proportion of taro to wheat flour 30:70, and a concentration of 4.5% konjac flour with a total expected value of 7.86.
... In this study, we embarked on a quest to efficiently produce tailor-made HM polysaccharides in yeast, by exploring how swapping the domains from two CSLA enzymes from konjac (a monocot) and Arabidopsis (a dicot) modulate its yield and composition. In the developing konjac corm (Gille et al., 2011), AkCSLA3 produces glucomannan that already has promising health care applications such as in the treatment of life style diseases (Behera and Ray, 2016). While AtCSLA2 is most important for seed mucilage biosynthesis in Arabidopsis (Yu et al., 2014;Voiniciuc et al., 2015), novel links between seed HM structure and salt tolerance provide an indication that fine-tuning HM structure could also be relevant for engineering stress-resistant crops (Yang et al., 2020). ...
Preprint
Full-text available
Background The carbohydrate polymers that encapsulate plants cells have benefited humans for centuries and have valuable biotechnological uses. In the past five years, exciting possibilities have emerged in the engineering of polysaccharide-based biomaterials. Despite impressive advances on bacterial cellulose-based hydrogels, comparatively little is known about how plant hemicelluloses can be reconstituted and modulated in cells suitable for biotechnological purposes. Results Here, we assembled cellulose synthase-like A (CSLA) enzymes using an optimized Pichia pastoris platform to produce tunable heteromannan (HM) polysaccharides in yeast. By swapping the domains of plant mannan and glucomannan synthases, we engineered chimeric CSLA proteins that made β-1,4-linked mannan in quantities surpassing those of the native enzymes while minimizing the burden on yeast growth. Prolonged expression of a glucomannan synthase from Amorphophallus konjac was toxic to yeast cells: reducing biomass accumulation and ultimately leading to compromised cell viability. However, an engineered glucomannan synthase as well as CSLA pure mannan synthases and a CSLC glucan synthase did not inhibit growth. Interestingly, Pichia cell size could be increased or decreased depending on the composition of the CSLA protein sequence. HM yield and glucose incorporation could be further increased by co-expressing chimeric CSLA proteins with a MANNAN-SYNTHESIS-RELATED (MSR) co-factor from Arabidopsis thaliana . Conclusion The results provide novel routes for the engineering of polysaccharide-based biomaterials that are needed for a sustainable bioeconomy. The characterization of chimeric cellulose synthase-like enzymes in yeast offers an exciting avenue to produce plant polysaccharides in a tunable manner. Furthermore, cells modified with non-toxic plant polysaccharides such as β-mannan offer a modular chassis to produce and encapsulate sensitive cargo such as therapeutic proteins.
... 101 It is confirmed that KGM has some health advantages such as improving immune function, decreasing cholesterol, normalizing triglyceride (TG) levels in the blood, boosting intestinal activity, and improving blood sugar levels, therefore it can be utilized properly as a nutritional supplement. 102 Furthermore, KGM has been utilized popularly in the food industry as a thickening and gelling agent because of its capability in creating viscous solutions and thermal-stable gelling property. 76 Xu et al 103 (Table 2). ...
Article
The application of petroleum polymers and plastics in food packaging is exhibiting an increasing trend, due to low price and desirable characteristics. Nevertheless, these polymers are non-biodegradable, nonrenewable, and require landfills. Edible polymers are suitable alternative for synthetic polymers, which can be consumed by animals or human beings without health risk. Edible packaging can protect the foodstuff from microbial and chemical deterioration during storage and distribution, which can lead to extend the quality and safety of packaged food. The plant gums as natural polymers are able to form films and coatings with good barrier properties against the transfer of gases such as oxygen, carbon dioxide, and moisture. This review summarized the production and characteristics of novel edible films and coatings based on plant gums such as tree exudate, seed, and tubers.
Chapter
Polysaccharides are abundant natural polymeric compounds found in plants, animals, and microorganisms with properties and essential human health. Polysaccharides are well known for positive effects on the immune, metabolic, digestive, gut microbiota, host epigenetics, brain function, and detoxification system. This chapter focuses on the various valuable properties of polysaccharides, particularly in biomedical applications.
Article
The objective of this research was to identify the structural and physicochemical factors of konjac glucomannan (KGM). Seven purified konjac flours that varied in hydration behavior and ultimate viscosity were selected and their compositional, molecular structural, and morphological properties were compared. The results suggested that the hydration rate and the development of solution viscosity were related to particle size and surface morphology of KGM particles rather than molecular structure. The particle size distribution value, D95, varied from 452.70 μm to 132.30 μm and the hydration time decreased from 90 mins to 8 mins, respectively. The ultimate viscosity of fully hydrated KGM solutions was not always associated with higher Mw. Our results show that lower main chain mannose to glucose (M/G) ratios led to lower viscosity and higher acetyl content exhibited higher viscosity compared to low-acetyl KGM of same Mw. The ultimate viscosity was found to be related to a greater degree of intermolecular interaction at concentrations above c*, indicated by higher n2 values, which is the slope of double logarithmic plots of ‘zero-shear’ specific viscosity versus degree of space occupancy (c[η]). Small angle x-ray scattering (SAXS) results suggested that molecular conformation was the key factor that affected n2, the larger hydrodynamic volume and greater intermolecular interactions that contributed to the larger n2. The results of this research identify physicochemical factors that are necessary for rational KGM structural design as a satiating ingredient in appetite regulation and body weight management.
Article
The properties of microencapsulated fish oil, prepared with spray drying and freeze-drying processes using emulsions of konjac glucomannan (KGM) and soybean protein isolate (SPI) was investigated. Comparative analysis of microcapsules showed the encapsulation efficiency of spray drying and freeze-drying were 90.10% and 83.52% respectively. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) results exhibited that microcapsules prepared with spray drying were spherical particles with a compact structure, while microcapsules prepared with freeze-drying were irregular particles with a pore-like structure. Release kinetics test further indicated retention rate of core materials for microcapsules prepared with spray drying were better than with freeze-drying. In addition, a human epithelial microfold cell (M-cell) transcytotic assay demonstrated that the M-cells had greater transport activity for the exogenous microcapsules.
Chapter
Over the years, there has been unprecedented progress in developing biopolymer-based systems and their applications in pharmaceutical and biomedical fields. The versatile applications of biopolymers are attributed to their biocompatibility, biodegradability, and low immunogenicity. Currently, several biopolymers extracted from animal or plant sources also exhibit therapeutic activities. Biopolymers are often suitably tailored to improve their physicochemical and biological properties. Eventually, their drug delivery applications are vastly improved and extended. Herein, an overview of the sources, chemical compositions, physicochemical properties, therapeutic potentials, and chemical modification approaches of various biopolymers is presented. An array of pharmaceutical excipients based on various biopolymers and their tailor-made forms are also reviewed.
Article
Scope: Konjac glucomannan oligosaccharides (KMOS) are prebiotics and may improve intestinal immunity through modulation of macrophage function. However, the underlying molecular mechanisms are still not clear. Methods and Results: Using a mouse model of dextran sulfated sodium (DSS)-induced acute colitis, we demonstrate here that KMOS (400 mg/kg/d) can ameliorate intestinal inflammation in a macrophage dependent manner. Oral exposure to KMOS prevented DSS-induced intestinal pathology, improved epithelium integrity, and decreased accumulation of colonic inflammatory leukocytes and cytokines. The therapeutic effects of KMOS are dependent on the function of macrophages, as depletion of macrophages abolished the effects. In colonic lamina propria of DSS-treated mice, as well as in vitro culture of bone marrow derived macrophages (BMDMs), KMOS skewed reprogramming of classically activated macrophages (CAM/M1) into alternatively activated macrophages (AAM/M2). We further determine that the activation of SIGNR1/phospho-c-Raf (S338)/phospho-p65 (S276)/acetyl-p65 (K310) pathway is responsible for KMOS-induced AAM/M2 polarization. Blockage of SIGNR1 abolished KMOS-induced AAM/M2 polarization of activated macrophages, expression of phospho-p65 (S276) in colonic macrophages, and alleviation of DSS-induced colitis in mice, suggesting that SIGNR1 is critical for macrophage responses to KMOS. Conclusions: This study reveals a SIGNR1-mediated macrophage-dependent pathway that supports regulatory function of KMOS in host immunity and intestinal homeostasis. This article is protected by copyright. All rights reserved
Article
Three asymmetric dicationic ionic liquids; 1-(2-(1-dodecyl-2-methyl-1H-imidazol-3-ium-3-yl)ethyl)-4-methylpyridin-1-ium bromide, 1-(6-(1-dodecyl-2-methyl-1H-imidazol-3-ium-3-yl)hexyl)-4-methylpyridin-1-ium bromide and 1-(10-(1-dodecyl-2-methyl-1H-imidazol-3-ium-3-yl) decyl)-4-methylpyridin-1-ium bromide (Ia, Ib &Ic respectively) were synthesized and characterized via Elemental analysis, FT-IR, ¹H-NMR, and Thermo-gravimetric analysis (TGA). Their surface activities were studied. The performance of the synthesized ionic liquids as oil spill dispersants were evaluated at different temperatures (10, 30 & 50 oC) and concentrations (750, 1500, 2000, 3000 ppm). Data reveals that the efficiency is ranked as follows: Ib > Ia > Ic with concentration of 1500 ppm.
Article
Amorphophallus is the only economic crop that can produce a large amount of glucomannan (KGM). However, heat stress can induce a variety of morphological and physiological changes in Amorphophallus, which also affects its growth, development, nutrition, and economic value. Heat shock transcription factors (Hsfs), as central regulators of the heat stress response, play a key role in protecting plants against heat stress and in regulating plant development. In this study, the AaHsfA1 gene was obtained from Amorphophallus albus, and sequence analysis confirmed that it was a typical class A Hsf. The qRT-PCR results demonstrated that AaHsfA1 was significantly upregulated in different tissues of Amorphophallus albus after heat stress. Meanwhile, allogenic transformation showed that AaHsfA1 could significantly improve the heat resistance of Arabidopsis under heat stress. Subcellular localization analysis revealed that AaHsfA1 localized to the nucleus and cytoplasm. Protein-protein interaction studies identified a direct interaction between AaHsfA1 and AaHsfA2a, AaHsfA1 and AaHsp70, but AaHsfA1 did not interact with AaHsfB1. In conclusion, this study provides theoretical and genetic references for analyzing the mechanism of Amorphophallus heat resistance formation and crop resistance breeding.
Article
Konjac glucomannan-based (KGM-based) films are new promising alternative materials for solving white pollutions and food safety concerns induced by traditional petroleum-based packaging materials. This paper reviews the current situation, the bottlenecks and the trend of future research of KGM-based films. Natural KGM-based films including biopolymer composite films, bio-nanocomposite films, emulsion films and physically or chemically modified films are summarized. Fabrication methods including solvent casting, microfluidic spinning and electrospinning are introduced. Functions of films including active packaging, intelligent packaging and edible packaging are summarized. Finally, the film formation mechanisms and promising trend of research are comprehensively analyzed and discussed. The upsurge of films research based on KGM is coming. Based on the comparison and analysis for published literatures, the key points for research primarily cover the following aspects: actual preservation effect and activity mechanisms of KGM-based films should be emphasized; new strategies need to be explored to improve the antibacterial activity of KGM-based films; various novel methods should be found to deal with the issue that KGM-based films have strong water solubility.
Article
This research presents the physicochemical property of the mixtures induced by blending konjac glucomannan (KGM) and welan gum (WL). The effects of the ratio and concentration on the rheological properties of the KGM and WL mixtures, such as shear rate and strain (large-amplitude oscillatory shear, frequency, temperature, time, stress relaxation, and creep), were studied. The combination analysis of Fourier transform infrared spectroscopy, scanning electron microscopy, thermodynamic differential scanning calorimetry, water mobility, and distribution property analyses through low-field nuclear magnetic resonance spectroscopy were used to determine the authenticity of gels. Finally, a model of the interaction force was constructed to elucidate the interaction mechanism when heating. The result showed that the mixtures of KGM and WL were pseudogel. The synergy effect was positively correlated with concentration, which was the strongest when the KGM (g/kg): WL (g/kg) ratio was 2:8. Abnormal temperature sensitivity (sudden drop of modulus around 30 °C) was observed at the ratio, and the mixture owned good temperature reversibility in 3 cycles. This work expanded the application scope of KGM and WL and provides a method for the determination of gels.
Article
The Amorphophallus bulbifer (A. bulbifer) as a newly developed superior konjac variety has the advantages of short growth cycle, high reproductive coefficient, disease resistance and adaptation to humid or hot environments. Because of its good growth characteristics and high konjac glucomannan (KGM) content, A. bulbifer has great potential to be used as KGM resources in food industry. However, KGM from the A. bulbifer flour has very high viscosity even in low concentration, and the gels formed by KGM are easily browning during the alkali-induced process. These shortcomings are key factors that limit its application in the food industry. In order to solve this problem, KGM was modified by citric-acid treatment (CAT), and the effect of CAT on the physicochemical and gel properties of KGM was investigated in this study. The results indicated that the apparent viscosity and ΔE value of the KGM treated with 1.2 M CAT for 2 h were 948.66 Pa·s and 14.55, respectively, which were significantly lower than native KGM in the same variety. Moreover, the CAT did not significantly affect the texture properties of KGM gels. Hence, it will be extremely valuable for developing innovative low-calorie foods favored by consumers and industrial production based on KGM.
Article
This work is dealt with how structural changes induced by konjac glucomannan (KGM) interacting with wheat protein contribute to dough properties upon the heating stage. It comparatively investigated the effects of KGM on gluten thermal-polymerization process from molecular weight, free sulfhydryl content, secondary structure and thermal stability, and then analyzed KGM-induced changes of structural and rheological properties of wheat dough with heating temperature increased. Results showed that KGM increased the average molecular weight, the β-sheet/β-turn ratio and denaturation temperature of gluten protein while decreased the content of free sulfhydryl groups. It was likely that KGM promoted the formation and stability of gluten networks upon heating by interfering sulfydryl interchange reactions and thermal denaturation. Dough structure was thus strengthened to a compact network and presented the increased elasticity and the raised resilience, springiness, cohesiveness and chewiness of textural properties by heating treatment.
Article
An anti-fouling aerogel with superior separation performance for separation of oil/water emulsion is of great significance to industrial development due to continuously increasing oily industrial wastewater. Herein, a superhydrophilic/underwater superoleophobic porous biobased aerogel with a three-dimensional network structure was prepared by the agricultural waste corn stalk (CS) incorporated with konjac glucomannan (KGM) through simple sol-gel and freeze-drying methods. The oil/water separation mechanisms and the effect of aerogel structural changes on the separation performance of CS/KGM aerogel for oil-in-water emulsions are discussed in detail. Using toluene as an oil phase, CS3.50K1.25 exhibited outstanding separation performance with an excellent separation efficiency above 96.26% and a high permeate flux above 2,381 L m−2 h−1 for oil-in-water emulsions. As expected, the separation efficiency and permeation flux can be wholly recovered after washing, indicating the aerogel possesses good sustainability. Moreover, CS/KGM aerogel has the advantages of low cost, simple preparation, eco-friendly and anti-fouling, revealing a promising candidate for the treatment of oily wastewater pollution.
Article
In this paper, the effect of konjac glucomannan (KGM) on the physical stability, rheological properties, and microstructure of Pickering emulsions stabilized by gliadin/sodium caseinate nanoparticles (Gli/CAS NPs) with different concentration was investigated. When the Gli/CAS NPs concentration was constant, the increase of KGM content significantly improved the storage stability of the emulsion. For emulsion samples with 20% oil content, with the increase of KGM concentration from 0.1 to 0.6%, the D32 value decreased from 7.57±0.24 μm to 4.47±0.10 μm. The CLSM and cryo-SEM observations showed that the particles adsorbed on the oil-water interface and formed a network structure. The structure was conducive to the stability of the emulsion. Irregular bulges on the surface of emulsion with higher KGM content could be observed. When the Gli/CAS NPs concentration was 4 wt%, the viscoelasticity of emulsion was improved and the G' and G" value of the emulsion increases with the increase of KGM content. The study showed that KGM has the potential to regulate the stability and rheological properties of emulsions, which might provide an interesting perspective for various industrial applications of functional emulsions.
Article
Abstract In today’s society, the incidence of diabetes is getting higher. It can cause a variety of complications and endanger human health. How to safely and effectively reduce blood sugar has become a hotspot of concern. Konjac dietary fibre is one of the most excellent soluble dietary fibres found so far. Its health benefits include weight loss, lowering blood fat and blood sugar, and it has a laxative effect. This article mainly reviews the clinical observations, related mechanisms of action, appropriate dosages and toxic side effects, providing a basis for the clinical application of konjac dietary fibre and proposing a new mechanism for its hypoglycaemic effect. It provides new ideas for the research and development of konjac in the prevention and treatment of diabetes.
Article
Composite hydrogels are known for their potential applications in drug delivery fields. Pure κ-carrageenan (KC) hydrogels have a drug burst release behavior, which greatly limit their applications. In this study, konjac glucomannan (KGM) was used to further improve the properties of soy protein isolate (SPI)/KC composite hydrogels. The results showed that the viscoelasticity of the composite hydrogels increased at KC/KGM ratio 9:1 due to the increase of hydrogen bond interaction. Excessive addition of KGM in composite hydrogels led to the increase in frequency dependence and gel network cavity as well as the decrease in gel cohesiveness. In vitro study on glucose release behavior of composite hydrogels showed that the glucose slow release behavior was enhanced by a small amount of KGM incorporation and had highly positive correlation with the gel viscoelasticity. These results suggested that KGM had the potential to enhance the properties and drug release characteristics of composite hydrogels.
Article
Background: In the context of the increasing prevalence of overweight and obesity worldwide, satiety-enhancing foods may help people control their energy intake and weight. In this study, an advanced near-real human gastric simulator equipped with a dynamic in vitro human stomach-IV (DIVHS-IV) system was used to determine the gastric digestion and gastric retention ratio of konjac flour (KF)/sodium caseinate (SC) mixtures with different ratios. Results: The apparent viscosity, viscoelastic properties, confocal laser scanning microscopy (CLSM) of the digested products were collected and analyzed to further study the effect of SC on the physical properties of KF during digestion. The results showed that the addition of SC could enhance the effect of KF on delaying gastric emptying in vitro. Besides, the addition of SC was shown to weaken the effect of gastric juice on the dilution of gastric contents by forming SC gel blocks in the acid environment. In particular, the synergistic gastric emptying delaying effect was the strongest in the KF/SC mixture containing 1% KF and 8% SC, and obvious massive aggregates were observed. Conclusion: The combination of 1% KF and 8% SC was shown to synergistically delay gastric emptying and potentially enhance the sense of fullness. © 2022 Society of Chemical Industry.
Article
Natural bio‐based materials used in wound dressings have been continuously developed in recent years, and have certain advantages in water retention, biocompatibility, and therapeutic properties. Konjac glucomannan (KGM) is a kind of plant polysaccharide with good cell compatibility and gel properties. Various gels obtained by modification of KGM through physical and chemical methods have great application potential in wound excipients. In the past few years, various KGM‐based wound barrier materials such as hydrogels, xerogel, microspheres, films, and fibers have been continuously researched and developed. The combination of KGM and other polymers can improve the problem of poor mechanical properties and give it new functional properties, which is beneficial to the moisturizing of the wound surface and the release of drugs to promote wound healing. This article reviews the physicochemical properties of KGM and the latest developments in KGM‐based composite gels, reveals the relationship between molecules in KGM‐based composite gels, and looks forward to the research and development prospects of KGM‐based composites in wound dressings.
Article
Background Dietary fibers, as mainly complex carbohydrates, offer various health benefits via modulating gut microbiota composition and promoting short chain fatty acids (SCFAs) production. However, the modern dietary habits are altered by reducing dietary fiber consumption and increasing intake of fat, sugar, and animal protein, thus adversely affecting our gut microbiota. This deficiency of dietary fibers is usually associated with an increasing risk of chronic diseases such as type 2 diabetes, cardiovascular diseases, and colorectal cancer. Scope and approach In this review, firstly we elaborately classified dietary fibers based on the definition by the European Food Safety Authority (EFSA), revealed the structure-activity relationship of dietary fibers, and up-dated carbohydrate active enzyme families (CAZyme). Furthermore, this review summarizes the available literature on the interaction between different types of dietary fiber, gut microbiota composition, and SCFA production, both in vivo and in vitro. Key findings and conclusions Dietary fiber-rich and WG-based diets offer a desirable nutritional intervention strategy by manipulating the composition and quality of microbiota to improve intestinal environment so as to promote host health.
Article
Blend of starch and polysaccharide is a secure and feasible modifying method for starch. Effects of konjac glucomannan (KGM) on pasting, retrogradation, rheological and structural properties of low-amylose rice starch were evaluated. KGM addition reduced the pasting temperature, breakdown and setback values, but raised the peak viscosity. When KGM concentration increased, the storage and loss moduli showed an upward trend. Fourier transform infrared spectroscopy (FTIR) showed redshifts at 3450 and 1640 cm−1 and suggested the formation of intermolecular hydrogen bond between KGM and starch molecules. X-ray diffraction (XRD) indicated that KGM decreased the relative crystallinity from 11.88 to 3.10%. Scanning electron microscopy (SEM) of KGM induced samples showed looser network structures, and confocal laser scanning microscopy (CLSM) detected less cloud-like blurry pastes surrounding around the starch ghosts. KGM addition suppressed the starch retrogradation. These results could be used to broaden the application of KGM in the food industry.
Article
Background: Konjac glucomannan (KGM) has been widely applied in food industry as thickening and gelation agent due to its unique colloidal properties of viscosity enhancement and gelling ability. The current study was aimed to prepare and characterize KGM and deacetylated KGM (Da-KGM) samples obtained by sonication in neutral and alkali ethanol-water solutions. Results: The results showed that the deacetylation degree (DD) of Da-KGM increased exponentially with alkali concentration. Fourier transform infrared spectra (FTIR) spectra further confirmed deacetylation reaction through the dramatic decrease in the acetyl group band at 1740 cm-1 . Besides, the high similarity among the tested groups in terms of X-ray diffraction (XRD) spectra implied a similar crystalline structure, while differential scanning calorimetry (DSC) curves revealed that the water binding capacity and decomposition temperature of KGM changed slightly with alkali and sonication treatment. The rheological profiles indicated that apparent viscosity (η0 ) of sonicated KGM samples was unchanged except for the T60 group (60 min sonication treatment). Particularly, ultrasonic treatment at high alkaline conditions (0.10 mol/L NaOH) was noted to promote deacetylation reaction, and the obtained samples showed decreased apparent viscosity and weakened the gelation process in aqueous solution. Partial correction analysis indicated that alkali rather than ultrasonic treatment resulted in the change of DD and η0 in Da-KGM. Moreover, sonication contributed to off-white color by reducing the browning caused by alkali in Da-KGM products. Conclusion: Ultrasound-mediated heterogeneous deacetylation reaction is a feasible way to prepare Da-KGM samples with lightened browning and controllable DD. This article is protected by copyright. All rights reserved.
Article
Compared with injection, oral drug delivery is a better mode of administration because of its security, low pain and simplicity. Insulin is the first choice for clinical treatment of type 1 diabetes, but, because insulin inability to resist gastrointestinal (GI) digestion results in poor oral bioavailability of insulin. Herein, we developed a targeted oral delivery system for diabetes. ConA-INS-KGM nanoparticles were prepared, loaded with insulin, fabricated from konjac glucomannan (KGM) and concanavalin A (ConA) through a crosslinking method, as an insulin oral delivery system in response to different blood glucose levels. The size of nanoparticles was characterized by TEM, which showed that these nanoparticles were formed spherical particles with a diameter of about 500 nm. In vitro release of insulin from these nanoparticles was studied, which indicated that insulin release is reversible at different glucose concentrations. In vivo tests demonstrated that they are safe and have high biocompatibility. Using the nanoparticles to treat diabetic mice, we found that they can control blood sugar levels for 6 h, retaining their glucose-sensitive properties during this time. Therefore, these nanoparticles have significant potential as glucose-responsive systems for diabetes and show great applications in biomedical fields.
Article
Full-text available
As a primary source of glucomannan, porang ( Amorphophallus oncophyllus Prain) has a decisive role in the food and non-food industry development. However, the naturally high calcium oxalate content in the corm is one obstacle why it is not safe as a food material. This paper describes and discusses the optimizing process to reduce the level of calcium oxalate content and improve the quality of the flour of porang locally grown in Lombok. Porang samples were obtained from the center of growing area in North Lombok. Series of trials were carried out, including treatment using a salt solution, blanching, and fermentation technology. The parameters observed in this study were the calcium oxalate content, moisture content, and the color of porang flour. The results from these trials indicated that soaking in salt solution and blanching technology significantly reduced the calcium oxalate concentration in the flour. However, the oxalate levels in the flour were slightly higher than the quality standard requirement. In contrast, fermentation treatment was not effective in reducing the oxalate level. In general, all treatments significantly reduced the flour-moisture content. Further research is required in order to produce quality local porang flour that meets quality standards.
Chapter
Tissue engineering involves the replacement and renewal of desired cells, tissues, and organs to restore the normal biological functions of specific cells or tissue types. Recently, the field is growing actively at both the laboratory and clinical levels contributing to research and medicines. The increase in population, changes in lifestyle, and better life expectancy have increased the chances of disease and trauma causing tissue damage which in turn leads to the need for advancement in the field of tissue engineering. The regeneration of the damaged tissues requires a supporting material known as a scaffold. The scaffolds are used for cell adhesion, proliferation, and differentiation for proper tissue regeneration and also help in vitro and in vivo drug and gene delivery to the biological system. The fabrication of the scaffolds is achieved by combining some biologically active materials known as biomaterials with some specific cell types that are needed for the desired tissue repair process. The natural polymers used as the biomaterials in the fabrication of scaffolds are especially gums that show excellent biological response and mimic the nature of the native extracellular matrix. This chapter briefly explains the gums used in tissue engineering, from where they can be derived, their classifications, properties, and applications.
Article
Full-text available
The objectives of the study are first, farmers in P4S Karya Tani can obtain superior porang seeds by regenerating porang in vitro culture through organic plus liquitermy fertilizer . Second, analyzing the media for growing tissue and the concentration of each porang plant media in P4S. Third, analysis of the supply chain structure of porang in P4S. This study uses quantitative and qualitative approaches with simple randomized design methods and SCOR methods. Based on the experiment, vitro culture of porang in P4S using liquitermy fertilizer , there were nineteen out of thirty porang plant accessions which had the potential as new clones for seedlings with an average tuber of 6.00 - 99.88% larger than the parent. The porang supply chain in P4S needs to be developed by involving wider stakeholders. This study shows that the seed production rate is better with liquitermy fertilizer in the porang in vitro culture. However, further evaluation is needed in analyzing genetic traits and glucomannan levels
Article
Carboxymethyl konjac glucomannan (CMKGM) is an anionic derivative of konjac glucomannan (KGM). Its coacervation with ovalbumin (OVA) was investigated through turbidity and coacervate yield measurements and the resultant CMKGM-OVA coacervates were characterized as a function of phase separation pH. The results indicated that CMKGM could coacervate with OVA in pHs ranging from 2.0 to 4.5. OVA to CMKGM mass ratios higher than 1:1 led to insoluble coacervates, while lower ratios conferred soluble complexes. NaCl suppressed the interaction between CMKGM and OVA and could resuspend their precipitated coacervates. The interaction between the two polyelectrolytes was not affected in temperatures ranging from 25 °C to 55 °C, but was weakened in higher temperatures. The coacervation increased the thermal stability and induced structural changes in both the polyelectrolytes. Atomic force microscope observation revealed that the CMKGM-OVA coacervates separated in mass ratio 1:1 was not susceptible to aggregation, and quartz crystal microbalance with dissipation analysis demonstrated that OVA exhibited the strongest absorption towards CMKGM in pH 3.0 in multilayer mode. Hence, CMKGM is a promising polyelectrolyte for coacervation with proteins and could be used in the construction of targeted delivery systems through the electrostatic interaction with oppositely charged biopolymers.
Chapter
Full-text available
This chapter focuses on nutritional and anti-nutritional factors, traditional processes for the removal of anti-nutrients, processing for flour, starch and discusses resistant starch from Elephant Foot Yams (EFY). Also, industrial utilization of Amorphophallus konjac into konjac flour and gum, glucomannan (KGM) and its applications as a food and pharmaceutical supplements are reviewed. The procedure for starch extraction from EFY is described by Amani et al. The EFY has many medicinal properties. In India, it is used in Ayurvedic drugs in the treatment of inflammatory conditions, hemorrhoids, rheumatism and gastrointestinal disorders. This flour produces a high viscosity and forms a gel by alkaline coagulant such as calcium hydroxide or by combining with secondary gum or co-gelated gum such as K-carrageenan and xanthan gum. In recent decades, methods for the extraction and purification of konjac glucomannan (KGM) have been studied and developed.
Conference Paper
Full-text available
Mammalian cells including cancer cells, stem cells and cell lines are important in the application of cells for therapies and research activities. They require the cells to be transported from the laboratory or surgery theater to the bedside, making it a challenge to be exposed at outside, shear stress condition and differences especially in the tropical climate countries. In this research, Konjac Glucomannan (KGM) and D-mannose were examined for their potential use in the delivery of cells when subjected to differences in and outside incubator conditions. The objective of this work was to examine the risk and effects of different type of sugar supplementation in the transportation of cells. In this study, we used mammalian cells; stem cells from human extracted deciduous tooth (SHED), human keratinocyte cell lines (HaCaT) and human breast cancer (MCF-7). We hypothesized that the supplementations of KGM and D-mannose in the culture medium will act as protective agents to the cells due to their unique biological properties interacting via carbohydrate-protein interactions. Experiments were conducted in laboratory conditions to compare the effect of these sugars on the viability of different type of cells when placed at inside and outside incubator condition for 24, 48 and 72 hours. Evaluation of cellular viability and proliferation showed that co-supplementation of KGM and D-mannose inhibited the viability of MCF-7 at both inside and outside incubator conditions while supplementation of these sugars to other cells cultured at outside incubator condition did improve cellular viability and morphology compared to the cells cultured at inside the incubator, elucidating the potential benefit of sugar glycobiology in cellular transportation.
Article
Full-text available
Amorphophallus konjac (konjac) is one among the major vegetable (tuber) crops grown in Asian countries. In China and Japan, it has been used as food and food additives for more than 1000 years. Over the last few decades, the purified konjac flour, commonly known as konjac glucomannan (KGM), a dietary fiber hydrocolloidal polysaccharide, has been introduced as a food additives as well as dietary supplement in many Asian and European countries. The present article reviews the literature (up to January 2015) covering the development of various functional foods, food additives from KGMs and their derivatives, Also, this review deals with global nutritional aspects and value added products of konjac corm.The bioprocessing techniques such as preparation, purification, extraction of KGM from konjac flour and methods to improve quality of KGM are discussed.
Article
Full-text available
In first part ofthis paper an overview is given about gfucomannans sources, characterisation and use for healing of human diseases. In the secondpart an experimental study is presented The study isfocused on assessing the contribution of the in vivo antioxidant properties of Candida utillis cell-wall glucomannan (GM) on its anti-arthritic effect. For this purpose not only biochemical methods were used but also chemiluminiscence measurements were performed in whole blood and in selected tissues, as spleen and hindpaw taken fiom arthritic rats treated with GM in two doses (7.5 mg/kgandof 15 mg/kg body weight) daily per os during 28 experimental days. Additionally, theJunctionality of neutrophils was evaluated byflow cytometry. An original approach was the determination ofCoQlevels in mitochondria of skeletal muscles inAA treated by GM. The anti-arthritic effect of GM in adjuvant arthritis was evidenced using evaluation with clinical parameters - hind paw volume and body weight of experimental Lewis rats. GM in vivo antioxidant activity has a large impact on this effect, both in the whole system and locally. The local effect ofGM was primarily exerted in the hindpaw tissue and mitochondria of skeletal muscles. As to the intensity of GM effects observed far the tested doses of 7.5 arul 15 mg/kg b. w., no significant difference was manifested; however the lower dose was more effective concerning the number of parameters affected The results suggest that Candida utilis cell-wall GM is a potential immunomodulative agent in treating exaggerated neutrophilic inflammation accompanying arthritis and thus GM seems to be beneficial for rheumatoid arthritis therapy.
Article
Full-text available
The uses of herbal medicines worldwide provide an excellent opportunity for India to look into the therapeutic compounds from ancient system of therapy, Ayurveda. Since ancient time, Amorphophallus campanulatus has been considered as medicinal plant with multiple protective activities. So, the present study was aimed to identify the various phytochemical constituents in the ethanolic and aqueous extracts of Amorphophallus campanulatus tuber by GC-MS analysis. The ethanolic and aqueous extracts of Amorphophallus campanulatus were dissolved in absolute ethanol (1 mg/ml). 10μl of this sample was then injected for gas chromatography- mass spectrometric (GC-MS) analysis. The results for the first time revealed the presence of several bioactive components both in the ethanolic as well as in the aqueous extracts. However, the ethanolic extract showed quantitatively higher amount of these components than the aqueous extract as is clearly indicated by higher % peak area of the compounds in the ethanolic extract. Some components of biological importance include Hexadecanoic acid and its methyl and ethyl esters, Heptadecanoic acid, Linoleic acid and its ester, Oleic acid, Stigmasterol, 1, 3, 5, benzenetriol, 4H-Pyran-4-one, 2, 3-dihydro-3, 5 -dihydroxy-6-methyl-, Squalene and Vitamin E. Thus the results of the present study is an evidence to support the traditional usage of A. campanulatus which possess several known and unknown bioactive components. By identifying and isolating these components, new drugs can be formulated to treat various diseases.
Article
Full-text available
The amelioration of aflatoxicosis in broiler chickens was examined by feeding two concentrations of yeast component (esterified glucomannan; EG). EG, incorporated into the diet at 0.5 and 1 g/kg, was evalu- ated for its ability to reduce the detrimental effects of 2 mg total aflatoxin (AF; 82.72% AFB 1, 5.50% AFB2, 10.20% AFG1 and 1.58% AFG 2) in diet on growing broiler chicks from 1 to 21 d of age. A total of 240 male broiler chicks (Ross-308) were divided into 6 treatment groups (control, AF, EG (0.5 g/kg), AF plus EG (0.5 g/kg), EG (1 g/kg), and AF plus EG (1 g/kg)). Compared to the control, AF treatment significantly decreased body weight gain from week 2 onwards. AF treatment also caused significant decreases in serum total protein, albumin, total cholesterol, triglyceride, glucose, inorganic phosphorus, creatinine levels and alanine-aminotransferase (ALAT) activity but increased the aspartate-aminotransferase (ASAT) activity. Red blood cell, haematocrit, haemoglobin, thrombocyte, and lymphocyte counts and tibial crude ash levels were significantly reduced by AF treatment, while significant increases were seen in heterophil counts. The addition of EG (1 g/kg) to an AF-containing diet significantly improved the adverse effects of AF on haematological parameters, total protein, albumin values and ASAT activ- ity. EG (1 g/kg) also partially improved body weight gains (59%) and the other biochemical parameters influenced by AF treatment. The addition of EG (both 0.5 and 1 g/kg) to the AF-free diet did not cause any considerable changes in the investigated values. These results clearly indicated that EG (1 g/kg) addition effectively diminished the adverse effects of AF on the investigated values. Also, the higher dietary concentration of EG (1 g/kg) was found more effective than the lower concentration (0.5 g/kg) against the adverse effects of AF on the variables investigated in this study.
Article
Full-text available
Glucomannan (GNN), a water-soluble dietary fibre derived from the plant Amorphophallus konjac, is marketed for weight reduction. The exact mechanisms by which GNN might exert its actions are unclear. However, it has been shown that GNN slows gastric emptying by forming a viscous gel of large volume, which increases the feeling of satiety. Current evidence on the effectiveness of GNN for weight reduction is sparse, and well-designed trials performed in children are needed to assess the efficacy of this modality. We aim to systematically evaluate the efficacy of GNN consumption for the management of children who are overweight or obese. Children aged 6-17 years who are overweight or obese (based on the WHO growth criteria) will be randomly assigned to receive GNN or placebo (maltodextrin) (both at a dose of 3 g/day) for 3 months and will be followed-up for 3 months. Before the intervention, all children will receive dietetic advice, and they will be encouraged to engage in physical activity. The primary outcome measure will be the body mass index-for-age z-score difference between the groups at the end of the intervention. The study was approved by the Bioethics Committee of the Medical University of Warsaw. The findings of this trial will be submitted to a peer-reviewed journal (paediatric, nutrition or gastroenterology). Abstracts will be submitted to relevant national and international conferences. NCT02280772. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Article
Full-text available
Background: Amorphophallus companulatus (Araceae) is a tuberous medicinal plant commonly used in Ayuvedic medicines as well as tribal medicines of India. Aim: Aim of the present study was to investigate the protective effect of A. companulatus tuber extracts against H 2 O 2 induced oxidative damage in human erythrocytes and leucocytes. Setting and Design : The experiment was set and design as per available method in the literatures. Three measurements were performed under each set of extracts. Materials and Methods: The extracts of tuber of A. companulatus such as methanol, ethanol, acetone (70%) and hydro-alcohol (1:1) used to assess catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione (GSH) and lipid peroxidation (LPO) levels of human erythrocytes and leucocytes. Statistical Analysis : All experimental data were statistically analysed and expressed as means ± SD by using the one-way analysis of variance. Results: Results of present studies revealed that, increased in the CAT, SOD, GPx and reduction of GSH and LPO levels in H 2 O 2 group compared with control group. The extracts of tuber of A. companulatus treated groups showed effective reduction of CAT, SOD, GPx and increased the GSH and LPO levels as compared with H 2 O 2 group on human erythrocytes and leucocytes. The methanol extract was found more effective than others. Conclusion: The present findings suggest that, the extracts of tuber of A. companulatus possess protective effect against H 2 O 2 induced oxidative damage. Furthermore, these tuber extracts may appeared to be beneficial in preventing H 2 O 2 oxidative human red blood cell (RBC) damage in human and can improve RBC membrane permanence. The tubers of A. companulatus are the potential source of natural antioxidants for the treatment and prevention of disease in which LPO takes place.
Article
Full-text available
The aim of this study was to analyze the effects of a 4-week-long consumption of glucomannan-enriched, aronia juice-based supplement on anthropometric parameters, membrane fatty acid profile, and status of antioxidant enzymes in erythrocytes obtained from postmenopausal women with abdominal obesity. Twenty women aged 45-65 with a mean body mass index (BMI) of 36.1 ± 4.4 kg/m(2) and waist circumference of 104.8 ± 10.1 cm were enrolled. Participants were instructed to consume 100 mL of supplement per day as part of their regular diet. A significant increase in the content of n-3 (P < 0.05) polyunsaturated fatty acids in membrane phospholipids was observed, with a marked increase in the level of docosahexaenoic fatty acid (P < 0.05). Accordingly, a decrease in the n-6 and n-3 fatty acids ratio was observed (P < 0.05). The observed effects were accompanied with an increase in glutathione peroxidase activity (P < 0.05). Values for BMI (P < 0.001), waist circumference (P < 0.001), and systolic blood pressure (P < 0.05) were significantly lower after the intervention. The obtained results indicate a positive impact of tested supplement on cellular oxidative damage, blood pressure, and anthropometric indices of obesity.
Article
Full-text available
This research studied the hypoglycemic effect of water soluble polysaccharide (WSP) extracted from yam (Dioscorea hispida) tuber by three different methods: aqueous extraction, papain assisted extraction, and tempeh inoculums assisted extraction. The two later extraction methods were aimed to remove WSP binding protein to have more pure WSP. The hypoglycemic activities were evaluated by means in vivo test on alloxan induced hyperglycemic rats, glucose response test (GRT), in situ glucose absorption test using everted sac, and short chain fatty acids (SCFAs) analysis. All yam WSP extracts exhibited ability to decrease blood glucose level in hyperglycemia condition as well as inhibited glucose absorption and SCFA formation. The order of hypoglycemic activity was tempeh inoculums assisted- >papain assisted- >aqueous WSP extracts. GRT and in situ glucose absorption test showed that order of inhibition was papain assisted- >tempeh inoculums assisted- >aqueous WSP extracts. Digesta of caecum of yam WSP extracts oral fed rats had more SCFA than control. Tempeh inoculums assisted WSP extract exhibited the most significant hypoglycemic activity.
Article
Full-text available
Purpose: Pulverized konjac glucomannan (PKGM) is a natural biologically active compound extracted from konjac, a Japanese traditional food. In the present study, we investigated the role of PKGM in intestinal immunity in a mouse model of oxazolone (OXA)-induced colitis. Methods: C57BL/6(B6) mice were fed PKGM or control food from 2 weeks before the induction of OXA colitis. Body weight change, colon length, and histological change in the colon were examined. The mononuclear cells were purified from colon and stimulated with PMA/ionomycin. The levels of TNF-α, interferon (IFN)-γ, interleukin (IL)-4, and IL-13 from the supernatant were measured by ELISA. Results: Oral administration of PKGM prevented the body weight loss and shortening of colon length associated with OXA-induced colitis. Histological analysis revealed that the colonic inflammation was improved by the administration of PKGM. The levels of IL-4 and IL-13, the critical inflammatory cytokines in OXA colitis, derived from mononuclear cells from the lamina propria of the colon were significantly suppressed by PKGM administration. PKGM-fed mice showed a significantly lower IL-4/IFN-γ ratio in the colonic lamina propria compared with that in control-fed mice. Fluorescence-activated cell sorting analysis revealed that natural killer (NK) 1.1(+) T cells in the liver were significantly decreased in PKGM-fed mice. Finally, the preventive role of PKGM in OXA-induced colitis was not observed in invariant natural killer T cell-deficient mice. Conclusions: PKGM ameliorated OXA-induced colitis in mice. This effect is associated with a decreased population of NK1.1(+) T cells and induction of Th1-polarized immune responses.
Article
Full-text available
Polysaccharides interact with cells in ways that can be conducive to wound healing. We have recently reported that konjac glucomannan (KGM) which is comprised of D-mannose and D-glucose linked by β-1,4 glycosidic chains, stimulates fibroblast proliferation. The aim of this study was to produce a range of crosslinked KGMs and bicomponent KGM containing hydrogels and to examine their potential for wound healing. Two types of KGM hydrogel were synthesized, biodegradable from crosslinked KGM and non-biodegradable by forming semi-IPNs and graft-conetworks with a second synthetic component, poly(N-vinyl pyrrolidinone-co-poly(ethyleneglycol)diacrylate) (P(NVP-co-PEGDA)), which was produced by UV initiated radical polymerization. Crosslinked KGM was formed by bimolecular termination of macro-radicals formed by oxidation with Ce(IV). Semi-IPNs were formed by copolymerization of NVP and PEGDA in the presence of KGM and in the graft-conetworks the KGM was also crosslinked using the Ce(IV) procedure. The hydrogels had different swelling properties and differences could be observed in their chemical structure using 13C solid state NMR, DSC and FTIR. Both forms were cytocompatible but only the graft-conetworks had the ability to stimulate fibroblast metabolic activity and to stimulate the migration of both fibroblasts and keratinocytes. In conclusion a form of KGM hydrogel has been produced that could benefit wound healing.
Article
Full-text available
Reaction of phenol with hydrogen peroxide over H-MFI, Fe-MFI, H-BEA, Fe-BEA and TS-1 zeolite catalysts was investigated. Over H-BEA, biphenyl product was observed. It is suggested, that the larger pore size of H-BEA facilitates coupling of two phenol molecules. Two distinct reaction mechanisms are proposed for acid and redox catalysts. Graphical Abstract
Article
The close relationship between bowel cancer and other non-infective diseases of the bowel, such as benign tumor, divert ocular disease, and appendicitis, indicates that these conditions may have a common or related etiology. Their close association with the refined diet characteristic of economic development suggests that the removal of dietary fiber may be a causative factor. These diseases are all rare in every community examined which exists on a high residue diet, and common in every country where a low residue diet has been adopted. Dietary fiber has been shown to regulate the speed of transit, bulk, and consistency of stools, and together with other dietary factors is probably also responsible for the changes which have been demonstrated in the bacterial flora of feces. It seems likely that carcinogens produced by the action of an abnormal bacterial flora when held for a prolonged period in a concentrated form in contact with the bowel mucosa may account for the high incidence of these diseases in economically developed countries.
Article
A primary function of the gastrointestinal tract is to provide the body with water, electrolytes and nutrients. It accomplishes this by ingestion, mechanical shearing, mixing and movement of the food through the gastrointestinal tract (motor events), secretion of digestive juices (≈ 6 liters per day) for degradation of complex nutrients into simple nutrients (e.g. complex carbohydrate into simple sugars), absorption of simple nutrients, water and electrolytes, and bacterial degradation of residue in the large bowel / elimination of waste. The small bowel is ≈ 7 meters long with a mucosa that is studded with millions of villi (each with microvilli), giving the small bowel a surface area approximately the size of a tennis court. Most digestion/absorption normally occurs early in the proximal small bowel. Non-digested/absorbed chyme arrives as a liquid in the cecum, and, under normal conditions, is gradually dehydrated as it slowly passes through the large bowel until it is eliminated as formed stool. Different types of dietary fiber can exert specific mechanical effects on each of these gastrointestinal functions, which can lead to local benefits (e.g. relief of constipation) as well as systemic benefits (e.g. cholesterol lowering, improved glycemic contro l ). Three characteristics of fiber (solubility, viscosity and fermentation) are predictive of the health benefits of different fiber types. Based on these three characteristics, dietary fiber can be divided into four clinically meaningful designations that support recommendations to address the specific healthcare needs of each patient. This review will describe the four clinically meaningful designations for dietary fiber, and provide a summary of the clinical studies that support the health benefits for each.
Article
Methanolic extracts of the tuber of Amorphophallus paeoniifolius were investigated for its antihelmintic activity against Pheretima posthuma and Tubifex tubifex. The extract with the concentrations of 25, 50 and 100 mg/ml were tested in the bioassay, which involved determination of time of paralysis and time of death of the worms. The extract exhibited significant antihelmintic activity at highest concentration of 100 mg/ml. Piperazine citrate (10 mg/ml) was included as standard reference and distilled water as control. The extracts were found not only to paralyze (Vermifuge) but also to kill the earthworms (Vermicidal).
Article
Amorphophallus paeoniifolius commonly known as "Jimikand", "Elephant foot yam" is one of the underutilized aroid of araceae family. It is one of the widely used tuberous, stout indigenous herbs used in ayurvedic medicine system for treating various human ailments. In recent years the popularity of complementary medicine has increased. The present review compiles the existing literature related to botanical description propagation, nutrient composition, phyto-chemical constituents, traditional uses, pharmacological actions and production of value added products of Amorphophallus paeoniifolius.
Article
Objective: The objective of the present study was to evaluate the antihyperglycemic and antinociceptive potential of methanol extract of Amorphophallus campanulatus corms in Swiss albino mice. Methods: Antihyperglycemic acivity was determined through oral glucose tolerance tests in glucose-loaded mice. Antinociceptive activity was determined through intraperitoneally administered acetic acid induced pain model in mice. Results: The extract, when administered to mice at doses of 50, 100, 200 and 400 mg per kg body weight, dose-dependently reduced blood glucose levels in glucose-loaded mice, respectively, by 28.8, 29.1, 35.3, and 37.4%. A standard antihyperglycemic drug, glibenclamide, when administered at a dose of 10 mg per kg body weight reduced blood glucose level by 40.7%. Thus the extract, at the highest dose tested, showed a near equivalent antihyperglycemic potency to that of glibenclamide. At the afore-mentioned four doses, the extract reduced the number of abdominal constrictions induced by intraperitoneal administration of acetic acid in mice by 30.4, 33.3, 42.4, and 45.5%, respectively. By comparison, a standard antinociceptive drug, aspirin, when administered to mice at doses of 200 and 400 mg per kg body weight, reduced the number of abdominal constrictions by 27.3 and 36.4%, respectively, demonstrating that the extract, even at the lowest dose, was more potent than the lower dose of aspirin. Conclusion: The results suggest that corms of the plant possess constituents with antihyperglycemic and antinociceptive activities, and which merits further isolation and identification.
Article
Konjac glucomannan ( KGM ) is a main component of natural materials konjac with broad biological function. This review summarizes the immuomodulatory effect of KGM on immune organ development, monocyte macrophage, natural killer cell, humoral immunity, cellular immunity, cytokines, and mucosal immunity.
Article
An environmentally-friendly wood adhesive was developed by blending konjac glucomannan (KGM), chitosan (CH), and polyvinyl alcohol (PVA) together. The viscosity of the KGM-CH-PVA (KCP) blend adhesive was determined, and the morphology of the film was observed using scanning electron microscopy (SEM). The KCP blend adhesive was applied to plywood during the manufacturing process, and the effects of the KGM, CH, and PVA contents on the bond strength was investigated. Results showed that KGM greatly increased the viscosity of the KCP blend adhesive, whereas the addition of PVA decreased the viscosity in the test range. The SEM observations showed that the KCP blend adhesive was homogeneous. The bond strength of the plywood that was treated with KCP blend adhesive increased with increasing KGM and CH concentrations, and desirable performance could be obtained with a total solids content of 4.6%. The KCP blend adhesive with 2.0% KGM, 2.0% CH, and 0.6% PVA exhibited a comparable bond strength with phenol formaldehyde. Findings suggest that the KCP blend adhesive can be used as a wood adhesive with all raw materials, having the advantage of being environmentally friendly.
Article
Major starch-producing aroids include Alocasia macrorrhiza (giant taro), Amorphophallus campanulatus (elephant foot yam), Colocasia esculenta (taro), Cyrtosperma merkusii (giant swamp taro), and Xanthosoma sagittifolium (cocoyam). Starch, as the major component of corms and cormels of these species, can amount over 80% of the dry weight. Lack of systematic information on these starches greatly limits the further development of aroids as cash crops. This review summarizes the current knowledge on the isolation, composition, granular and molecular structures, physicochemical properties, modifications, and uses of aroid starches. Future research directions on aroid starches are suggested.
Article
Dietary fiber consists of the structural and storage polysaccharides and lignin in plants that are not digested in the human stomach and small intestine. A wealth of information supports the American Dietetic Association position that the public should consume adequate amounts of dietary fiber from a variety of plant foods. Recommended intakes, 20-35 g/day for healthy adults and age plus 5 g/day for children, are not being met, because intakes of good sources of dietary fiber, fruits, vegetables, whole and high-fiber grain products, and legumes are low. Consumption of dietary fibers that are viscous lowers blood cholesterol levels and helps to normalize blood glucose and insulin levels, making these kinds of fibers part of the dietary plans to treat cardiovascular disease and type 2 diabetes. Fibers that are incompletely or slowly fermented by microflora in the large intestine promote normal laxation and are integral components of diet plans to treat constipation and prevent the development of diverticulosis and diverticulitis. A diet adequate in fiber-containing foods is also usually rich in micronutrients and nonnutritive ingredients that have additional health benefits. It is unclear why several recently published clinical trials with dietary fiber intervention failed to show a reduction in colon polyps. Nonetheless, a fiber-rich diet is associated with a lower risk of colon cancer. A fiber-rich meal is processed more slowly, which promotes earlier satiety, and is frequently less calorically dense and lower in fat and added sugars. All of these characteristics are features of a dietary pattern to treat and prevent obesity. Appropriate kinds and amounts of dietary fiber for the critically ill and the very old have not been clearly delineated; both may need nonfood sources of fiber. Many factors confound observations of gastrointestinal function in the critically ill, and the kinds of fiber that would promote normal small and large intestinal function are usually not in a form suitable for the critically ill. Maintenance of body weight in the inactive older adult is accomplished in part by decreasing food intake. Even with a fiber-rich diet, a supplement may be needed to bring fiber intakes into a range adequate to prevent constipation. By increasing variety in the daily food pattern, the dietetics professional can help most healthy children and adults achieve adequate dietary fiber intakes.
Article
The water binding properties of konjac glucomannan (KGM) and carboxymethyl konjac glucomannan (CMKGM) are important for their application in food, pharmaceutical, and chemical engineering fields. The equilibrium moisture content of CMKGM was lower than that of KGM at the relative humidity in the range 30-95% at 25°C. The water absorption and solubility of CMKGM in water solution were lower than that of KGM at 25°C. Carboxymethyl modification of KGM reduces the water adsorption, absorption, and solubility. Both carboxymethylation and deacetylation could confer hydrophobicity for CMKGM. These data provide the basis for expanding CMKGM application. Copyright © 2015 Elsevier Ltd. All rights reserved.
Article
The objective of this work was to determine the effects of ingested depolymerised glucomannans on wound healing. Mice were divided into four groups of twenty each: control - drinking water; control - drinking water containing 5% (w/v) glucomannan hydrolysate (GMH); test - drinking water with punched ear and; test - drinking water containing 5% (w/v) GMH with punched ear. Healing scores were recorded over eight days while body weight was taken four times over the trial period. There was faster healing for the group drinking water containing GMH. The consumption of hydrolysed glucomannan may encourage wound healing due to a number of immunosupportive effects.
Article
Konjac glucomannan, a reserve polysaccharide from Amorphophallus koniac tubers was isolated in a homogeneous state and is known to contain D-mannose and D-glucose in a molar ratio of 1.6:1. Survival of some monosaccharides after the periodata oxidation and subsequent reduction of knojac glucomannan suggested that it was composed mainly of β-1, 4 linkages, however, there was some branching in the polysaccharide. By analysis of the hydrolyzate of the permethylated sample by GC-MS, the branching structure through C3 of both D-mannose and D-glucose residues was confirmed. Yields of O-methyl mugars were also determined. The results indicate a branched structure for a native and non-denatured specimen of konjac glucomannan.
Article
Application of micrometre-scale konjac gel as fat analogue in mayonnaise was studied. Three concentrations of konjac glucomannan (KGM) were applied to prepare micronized konjac gel. The best combination of fat analogue used in mayonnaise was 4.0 wt% konjac glucomannan and 0.36 wt% sodium carbonate. Then fat was partially substituted by micrometre-scale konjac gel at levels of 10, 20, 30, 40, 50, and 60% which were referred to as R10, R20, R30, R40, R50, or R60 formulations, respectively while the full fat (R0) mayonnaise without konjac gel substitution was used as a control experiment. The effects of substitution ratio was determined by rheology measurements, colour measurements, optical microscope observation and caloric values analysis which indicated that fat in mayonnaises substituted with konjac gel of not more than 30% was acceptable. At the meanwhile, the product has good storage stability in a certain storage period. This study shows good potential for spent micronized konjac gel to be used as a fat analogue in mayonnaise.
Article
Glucomannan (GM), a soluble fiber derived from the plant Amorphophallus konjac, is marketed as being helpful in reducing body weight. However, the data supporting this claim are scarce. We aimed to systematically evaluate the effects of GM on body weight (BW) and body mass index (BMI) in otherwise healthy obese or overweight children and adults.Methods The MEDLINE, EMBASE, CENTRAL, and Google Scholar databases were systematically searched up to June 2014 for randomized controlled trials (RCTs) assessing the effectiveness of GM compared with placebo. The primary outcome measures were BW and BMI.ResultsSix eligible RCTs, only one performed in children, were included. In adults, three RCTs reported a significant reduction in BW in the GM group compared with the control group at the following different time points during the intervention: at week 2 (mean difference [MD] 0.21 kg, 95% confidence interval [CI] [0.13 to 0.29]); at week 4 (MD 2.04, 95% CI [0.52 to 3.56]); at week 5 (MD 1.3, 95%CI [0.89 to 1.71]); and at week 8 (MD 3.17, 95% CI [1.29 to 5.05]). Only one RCT reported the beneficial effect at more than one time point. None of the RCTs reported a favorable effect of GM on BMI.Conclusion In otherwise healthy overweight or obese adults, there is some evidence that in the short term GM may help to reduce BW, but not BMI. Data in children are too limited to draw any conclusions.Key wordsbody mass indexweightobesityoverweightglucomannanAbbreviationsACA, available case analysisBW, body weightGM, GlucomannanITT, intention-to-treatPP, per protocol