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Quantitative Determination of Allicin in Garlic: Supercritical Fluid Extraction and Standard Addition of Alliin
Abstract
A quantitative method is described for the determination of allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester) in garlic, using standard additions of alliin (l-(+)-S-allylcysteine sulfoxide) in conjunction with supercritical fluid extraction (SFE) and high performance liquid chromatography analysis with UV-vis absorbance detection. Optimum CO(2)-SFE conditions provided 96% recovery for allicin with precision of 3% (RSD) for repeat samples. The incorporation of an internal standard (allyl phenyl sulfone) in the SFE step resulted in a modest improvement in recovery (99%) and precision (2% RSD). Standard additions of alliin were converted to allicin in situ by endogenous alliinase (l-(+)-S-alk(en)ylcysteine sulfoxide lyase, EC 4.4.1.4). Complete conversion of the spiked alliin to allicin was achieved by making additions after homogenization-induced conversion of the naturally occurring cysteine sulfoxides to thiosulfinates had taken place, thus eliminating the likelihood of competing reactions. Concentration values for allicin determined in samples of fresh garlic (Allium sativum L. and Allium ampeloprasum) and commercially available garlic powders (Allium sativum L.) by standard addition of alliin were found in all cases to be in statistical agreement (95% confidence interval) with values determined using a secondary allicin standard (concentration determined using published extinction coefficients). This method provides a convenient alternative for assessing the amount of allicin present in fresh and powdered garlic, as alliin is a far more stable and commercially prevalent compound than allicin and is thus more amenable for use as a standard for routine analysis.
... Garlic began to garner interest once again when Cavallito and Bailey (1944) identified the main compound responsible for the antimicrobial properties of garlic as allicin, a thiosulfinate that comprises more than 70% (w/w) of thiosulfinates extracted from fresh garlic (Rybak et al. 2004;Salehi et al. 2019). Since then, garlic along with its chief bioactive component allicin has been associated with a wide range of antimicrobial properties as well as beneficial effects towards the cardiovascular and immune system (Harris et al. 2001;Oosthuizen et al. 2018). ...
... Allicin is the most abundant thiosulfinate found in garlic (Cai et al. 2008). It is reported that approximately 3.4 to 4.6 mg of allicin can be extracted from every gram of fresh garlic (Rybak et al. 2004). However, the concentrations of alliin and alliinase vary with different garlic species (Wu et al. 2014). ...
... Due to its reactive nature and depending on the environmental and/or processing conditions (Harris et al. 2001;Majewski 2014), allicin will react with thiol groups from other proteins or from itself to form bioactive compounds such as ajoenes, vinyldithiins and sulphides (Jacob and Anwar 2008) identified as DAS, DADS and DATS. It is noteworthy to remember that ajoenes and vinyldithiins are produced as a result of the decomposition of allicin in the presence of solvents that are less polar than water (Rybak et al. 2004). On the other hand, the preparation of allicin at − 70°C in dilute aqueous solutions has been observed to be stable over a 2-year period and has been speculated to remain stable beyond 2 years (Koch and Lawson 1996;Borlinghaus et al. 2014). ...
Garlic (Allium sativum L.) is a well-known spice widely utilised for its medicinal properties. There is an extensive record of the many beneficial health effects of garlic which can be traced back to as early as the ancient Egyptian era. One of the most studied properties of garlic is its ability to cure certain ailments caused by infections. In the 1940s, the antimicrobial activities exhibited by garlic were first reported to be due to allicin, a volatile compound extracted from raw garlic. Since then, allicin has been widely investigated for its putative inhibitory activities against a wide range of microorganisms. Allicin has demonstrated a preference for targeting the thiol-containing proteins and/or enzymes in microorganisms. It has also demonstrated the ability to regulate several genes essential for the virulence of microorganisms. Recently, it was reported that allicin may function better in combination with other antimicrobials compared to when used alone. When used in combination with antibiotics or antifungals, allicin enhanced the antimicrobial activities of these substances and improved the antimicrobial efficacy. Hence, it is likely that combination therapy of allicin with additional antimicrobial drug(s) could serve as a viable alternative for combating rising antimicrobial resistance. This review focuses on the antimicrobial activities exhibited by allicin alone as well as in combination with other substances. The mechanisms of action of allicin elucidated by some of the studies are also highlighted in the present review in order to provide a comprehensive overview of this versatile bioactive compound and the mechanistic evidence supporting its potential use in antimicrobial therapy.
... Considerable evident shows that allicin is the chief vigorous constituent of garlic, containing of up to 70% of total thiosulfates [8]. Garlic has been established to have antioxidant properties and immunomodulation and antimicrobial activities in poultry [9,10]. Garlic also minimizes the problem of emerging circulatory sicknesses and its influences, heavy weight, insulin resistance and tumors [11]. ...
... The addition of two to ten percent of partially dried garlic to the egg laying hens had no significant effect on productivity, heaviness or quantity of egg [9]. Modern researchers revealed that adding garlic powder of five or 10 g/kg increased number of days the hen lays egg n and a significantly increased weight of egg [19]. ...
... It is an essential step as this releases alliinase enzyme and helps in its interaction with alliin and in turn the production of allicin. The grinding can be done with any grinding equipment with maximum crushing strength to ensure enzymatic yield (Michael et al., 2004). The crushed garlic is then transferred to a beaker filled with cold water and capped followed by vigorous shaking for a few seconds and the step was repeated with addition of more cold water. ...
... The calibration is essential for maximum yield of allicin. Sulfones are used as an internal standard for comparison due to its similarity in its characteristics to thiosulfinates (Michael et al., 2004). The cell wall and the external structure of garlic is completely dissolved and fractured in microwave extraction (Sankhadip et al.,2014).Lower temperature is used to avoid allicin degradation in Pressurized Liquid Extraction. ...
... Commercial garlic preparations may be standardized to a fixed alliin and allicin content. [34] Garlic inhibits platelet aggregation in vivo in a dose-dependent fashion. [35] The effect of one of its constituents, ajoene, appears to be irreversible and may potentiate the effect of other platelet inhibitors such as prostacyclin, forskolin, indomethacin, and dipyridamole 36. ...
... Although in one clinical study garlic oil selectively inhibited CYP2E1 activity, it is still difficult to predict drug interactions with garlic. [33][34][35][36][37][38][39][40][41][42][43][44][45] Clove Anticoagulants and antiplatelets: Clove has been associated with inhibiting platelet aggregation (increasing INR, and report of disseminated intravascular coagulation. ...
ABSTARCT Hemostasis is the process of formation of clots within the walls of damaged blood vessels. To prevent abnormal bleeding and to maintain intravascular blood in a fluid state, in this study we aimed to evaluate the possible anticoagulant effect of aqueous extracts of Ginger, Garlic, Green tea and Clove. The aqueous extracts of Ginger, Garlic, Green tea and Clove were tested for in vitro prothrombin time (PT) test. The in vitro anticoagulant effects examined by using plasma, collected from blood samples of normal individuals by measuring PT. Ethylenediaminetetraacetic acid (EDTA) and saline in distilled water were used as a negative and positive control, respectively. The extract plasma was subjected to anticoagulation activity and was compared with EDTA-plasma and saline plasma. The observed prolonged prothrombin activity could be due to the presence of certain phytochemical constituents in the crude extract. The crude extracts and further, the active principles could be isolated and evaluated for clinical or physiological purposes. In vitro, anticoagulant activity studies results demonstrated that the all four aqueous extracts possess pharmacologically active anticoagulant components which could be helpful in preventing blood clot.
... Here we assume that these two peaks may represent allicin and alliin which are naturally occurring organic compounds found abundant in garlic and other plants of the genus Allium such as shallots and onions. Both organic compounds have been reported by several researchers in garlic via HPLC analysis with more or less the same retention times in their chromatograms (between 3 and 15min -depending upon the methodology and equipment) [38][39][40][41]. ...
Nitric Oxide (NO) regulates important physiological functions. Garlic (Allium sativum) is an important food component consumed fresh and processed for thousands of years. It has high L-arginine, which contributes to the NO system in the body. Both garlic and NO impact important physiological processes. Here we produced brown garlic, with significantly higher nutritional and therapeutic value compared to fresh and black garlic. Lower exhaled NO was recorded in asthmatic mice fed with brown garlic but with higher blood SNOs and no change in eNOS and iNOS expression. Lung biopsy showed reduced eosinophil accumulation in asthmatic mice fed with brown garlic. Real-time PCR and Western blot analyses indicated high expression of antioxidant genes but reduced interleukin genes, IL-4, IL-5, IL-6, IL-13, IL1β, and TNF-α brown garlic-fed asthmatic mice as compared to that in fresh and black garlic-fed asthmatic mice. This study provides the first comprehensive and conclusive insight into the nutritional benefits of brown garlic and its therapeutic value for the treatment of asthma in animals.
... For comparison, external standard curves were also prepared using silymarin compounds dissolved in the initial UHPLC mobile phase. The method of standard addition has been used for the chemical standardization of other botanical extracts including extracts of licorice, 23 garlic, 24 and botanical mixtures. 25 Here, we report the development and standardization of a quantitative assay for six milk thistle flavonolignans plus taxifolin in milk thistle extract using electrospray UHPLC-MS/MS that is fast, sensitive, and accurate. ...
Extracts prepared from the seeds of the medicinal plant milk thistle [Silybum marianum (L.) Gaertn. (Asteraceae)] are widely used as dietary supplements due to anti-inflammatory, antitumor, and hepatoprotective effects. Called silymarin, the main components of lipophilic extracts of milk thistle seeds are flavonoids and flavonolignans including silybin A, silybin B, isosilybin A, isosilybin B, silydianin, silychristin, taxifolin, and 2,3-dehydrosilybins. The aim of this study was to develop a method based on UHPLC-MS/MS for the chemical authentication and standardization of milk thistle silymarin. Validation included the method of standard addition to account for the lack of a blank matrix. Potential matrix effects were investigated by analyzing silymarin standards dissolved only in the initial UHPLC mobile phase. Measurements of six flavonolignans and taxifolin in the milk thistle extract using UHPLC-MS/MS with standard addition or external standard calibration produced similar results for all analytes except silydianin and 2,3-dehydrosilybin B, which showed significant peak enhancement during negative ion electrospray due to botanical matrix effects. The UHPLC-MS/MS-based method of standard addition requires <10 min per injection and is suitable for the standardization of silymarin from milk thistle in support of preclinical and clinical studies of safety and efficacy.
... Nonetheless, it is described as one of the most degraded compounds due to prolonged storage [62]. Allicin, one the most important biologically active compounds found in crushed or homogenized garlic, is extremely unstable due to the presence of a thiol group [72,73], and its half-life varies depending on the concentration and temperature of the storage solvent [74]. S-allyl-L-cysteine is a very stable compound [75], its content increasing during storage [62], as a result of the hydrolysis of γ-glutamyl-Sallyl-L-cysteine (GSAC) by the γ-glutamyl transferase enzyme (γ-GTP, EC 2.3.2.2) [75], and unaffected during fermentation and packing steps, similarly to other organosulfur compounds [62]. ...
The Italian garlic ecotype “Vessalico” possesses distinct characteristics compared to its French parent cultivars Messidor and Messidrôme, used for sowing, as well as other ecotypes in neighboring regions. However, due to the lack of a standardized seed supply method and cultivation protocol among farmers in the Vessalico area, a need to identify garlic products that align with the Vessalico ecotype arises. In this study, an NMR-based approach followed by multivariate analysis to analyze the chemical composition of Vessalico garlic sourced from 17 different farms, along with its two French parent cultivars, was employed. Self-organizing maps allowed to identify a homogeneous subset of representative samples of the Vessalico ecotype. Through the OPLS-DA model, the most discriminant metabolites based on values of VIP (Variable Influence on Projections) were selected. Among them, S-allylcysteine emerged as a potential marker for distinguishing the Vessalico garlic from the French parent cultivars by NMR screening. Additionally, to promote sustainable agricultural practices, the potential of Vessalico garlic extracts and its main components as agrochemicals against Xanthomonas campestris pv. campestris, responsible for black rot disease, was explored. The crude extract exhibited a MIC of 125 μg/mL, and allicin demonstrated the highest activity among the tested compounds (MIC value of 31.25 μg/mL).
... . Garlic also has a powerful antimicrobial effect (Onibi et al., 2009). Allicin, which generally comprises more than two thirds of the total thiosulfinates, is the principal sulphur comprising ingredients in garlic (Rybak et al., 2004). It has been stated that allicin and its derivatives are considered a larvicide and bacteriostatic, which act effectively against gram-positive or gram-negative organisms, as well as fungi such as Candida albicans and influenza virus (Chang & Cheong, 2008). ...
Background
Alternatives to antibiotics have been suggested by banning their use in the poultry industry. Garlic and mushroom are two important phytobiotic compounds in poultry nutrition.
Objectives
This study was conducted to evaluate the effects of supplementing diets with garlic and mushroom powder (MP) on growth performance, humoural and cellular immunity, and white blood cell counts of broiler chickens.
Methods
Five hundred and seventy‐six 1‐day‐old male broiler chickens (Ross 308) were assigned to 8 treatments with 6 replications (12 birds per replication) based on a completely randomized design in a factorial arrangement of 4 × 2 with 4 levels of garlic powder (GP; 0.00%, 0.50%, 1.00%, and 1.50%) and two levels of MP (0.00% and 1.00%).
Results
No significant effects of GP and MP on the growth performance and cutaneous basophil hypersensitivity were observed (p > 0.05). According to the regression equation, with increasing levels of GP in the diets, the relative weight of the bursa of Fabricius and thymus increased (p < 0.05). The effect of increasing levels of GP on the Newcastle disease virus (NDV) titre was greater in the absence of MP (p < 0.05). With increasing levels of GP in the diets, the percentages of lymphocytes and heterophils to lymphocytes ratio increased and reduced, respectively (p < 0.05).
Conclusions
This experiment has revealed that increasing the level of GP improved the immune response of broilers without affecting performance. The effect of increasing the level of GP on the NDV titre was more significant in the absence of MP.
... However, it is difficult to directly determine it due to its high reactivity and unstable nature. The range of the amount of allicin in garlic samples is reported by several scientists from 3.37 to 8.99 mg/g Ribak et al., 2004;Silva et al., 2010). The quantity of alliin indicates the quality of garlic. ...
The rhizosphere is the thin region of soil directly influenced by root secretions and microbes, known as the root microbiome. The rhizosphere associated with the roots of a plant contains numerous beneficial bacteria, fungi, and other microorganisms. Microbial constitution plays a vital role in a plant's growth cycle by stimulating its morphology, physiology, and development. Several species in the soil rhizosphere are supportive of plant growth, development, and productivity. The beneficial plant-microbe relationship within the rhizosphere is the key determinant of soil health and plant growth. Plant growth-promoting rhizobacteria support the colonization of AM fungi within plant roots. In the current study, garlic plants were treated with six different biological strains treatment, a combination of specific PGPR (Azotobacter and Azospirillum), PSB, KSB, Bacillus, and AM fungal inoculums. The output from these treatments was considered in different parameters determining the quality and productivity of garlic crops. These microbes help the plants directly or indirectly through the acquisition of nutrients, overall improvement in growth by production of phytohormones, protection from pathogens and other abiotic stressors. Results showed a significant increase in several factors such as nutrient translocation, bulb size, bulb diameter, biological biomass, marketable yield, and AM fungi colonization in root systems in contrast with standard treatment (Control (100% RRF and 50% RRF). Treatment T7 Absolute consortium PGPR + AM fungi (Azotobacter, Azospirillum, Pseudomonas, Frateuria, Bacillus, and AM fungi) performed better than control and other combinations of biological ingredient's utilization in different treatments and combinations. After harvest, garlic bulbs treated with Absolute consortium PGPR + AM fungi increased the Alliin content as well as the primary element responsible for garlic's medicinal properties and its distinctive native taste. Maximum yield (137.15±1.45q ha-1) was recorded in treatment T7, along with maximum values of dry matter (34.45±0.24), TSS (13.354%), starch (5.65%), reducing sugar (1.98%) and Alliin content (0.11 µg) as compared with control and other biological treatments. The best treatment in respect of projected yield was Absolute consortium PGPR + AM fungi) followed by control (50% RRF).
... The rupture of garlic bulbs leads to the formation of thiosulfinates, in which the precursor compound alliin is transformed into allicin (diallyl thiosulfinate) by enzymatic action; allicin is the most important bioactive compound in garlic due to its broad functional activity and high concentrations (Lawson & Hughes, 1992). However, alliinase, which catalyzes the conversion of alliin to allicin, is thermolabile, as is allicin; the latter decomposes within a few hours to form more stable sulfur compounds that have reduced activity (Rybak, Calvey, & Harnly, 2004). ...
... En outre, des travaux dans ce domaine ont également porté sur la valorisation des résidus de certains processus comme le résidu de raisin et de certains déchets végétaux [129]. Un nombre important de produits à base de plantes et espèces comestibles ont fait l'objet de la technologie de l'extraction par fluide supercritique, notamment l'abricot (Prunus armeniaca L.) [130][131][132][133], la carotte (Daucus carota L.) [134][135][136], la noix de cajou (Anacardium occidentale L.) [137][138][139], le cacao (Theobroma cacao) [24,140], l'ail (Allium sativum) [141][142][143][144], le gingembre (Zingiber officinale) [145][146][147][148][149], laurier (Laurus nobilis L.) [150][151][152][153], l'orange (Citrus sinensis L.) [154][155][156][157], l'origan (Origanum virens L.) [158][159][160][161][162] et le soja [163][164][165][166][167]. ...
Cette étude porte sur l’analyse fondamentale et expérimentale du processus d’extraction des huiles végétales par CO2 supercritique. Dans une première partie on s’est focalisé sur l'extraction de l'huile de noyaux de dattes où une étude paramétrique des trois facteurs pression (150-250 bar), température (40-60°C), et diamètre des particules (0.3-0.9mm) a été réalisée dans le but d'optimiser le procédé à l'aide de la méthodologie de surfaces de réponse. Un rendement optimal de 14.26% a été obtenu à 250 bar, 60°C et un diamètre de 0.3 mm. La technique de la Détente Instantanée Contrôlé DIC a été appliquée sur la poudre des noyaux de dattes avant d’en extraire les huiles végétales. Ce traitement a permis d’accéder à une expansion et de parvenir à une intensification de processus de l’extraction de point de vue rendement (15% d'augmentation relative), et durée d'extraction (amélioration d’environ 30%). La deuxième partie de cette étude est consacré à l'extraction de l'huile de sésame dans laquelle une exploration de l'effet des conditions opératoires (température, pression et masse initiale) sur le rendement en huile de graines de sésame a été réalisée un rendement optimal de 51.03% a été obtenu pour une pression de 250 bar, une température de 40°C et une masse initiale de 50g. En outre, un couplage de la technique du pressage à froid avec l'extraction par CO2 supercritique a été réalisé, et les résultats obtenus ont été comparés avec ceux obtenus par couplage avec l'extraction par hexane (technique de Randall). Le model phénoménologique de
Shrinking Core a été adopté pour la modélisation et la simulation du procédé d’extraction supercritique des deux substances étudiées, et les résultats montrent la fiabilité et la validité de ce modèle
... The effect of fresh garlic (Allium sativum L) extract against Candida has been presented in vitro and has been ascribed to the action of allicin [20], a sulfur-containing compound that is formed at levels of approximately 3-5 mg/g of freshly crushed or sliced garlic cloves [21], which was exhibited by previous investigators to impede the proliferation of bacteria and fungi [3,22]. Allicin has the capability to shield against the overgrowth of C. albicans and diminish the risk of candida attaching itself to the cells lining the oral cavity [23]. ...
Introduction:
The oral cavity is considered to be one of the most intricate environments in the human body. It is known to harbor commensal microorganisms that do not cause diseases, such as Candida albicans, a yeast fungus that has a carriage rate that tends to increase with age. It is worth noting that C. albicans can be readily identified within the flora of the gastrointestinal tract in 80% of healthy patients. Traditional medicine has alternatively been shown to play a key role in various health amenities with a wide spectrum anti-microbial effect against various yeast molds.
Objectives:
To evaluate the antifungal efficacy of pure garlic, onion, and lemon juice extracts against C. albicans. Materials and methods: C. albicans (ATCC 10231) were sub-cultured in brain agar followed by anaerobic incubation for 48 hours at 37°C. Ten plates were used for each of the materials studied to evaluate their antifungal efficacy against C. albicans. The efficiency of commercially available fresh garlic, onion, and lemon was tested in isolation against C. albicans. One-way ANOVA and chi-square were used for comparison between the different materials. The inhibition zone was measured, and the level of statistical significance was set at ≤0.05.
Results:
The diameter of inhibition zones has been measured along the vertical and horizontal axis. No inhibition zones were observed for the onion and lemon extracts used in this study whereas the garlic extract exhibited inhibition zones with altered sizes (4.89 ± 0.275). A highly significant difference was observed between groups (P = 0.000) and between garlic and the other materials (P = 0.000).
Conclusions:
Pure garlic showed a highly significant antifungal efficacy when compared to the onion and lemon juice extracts against C. albicans. Further studies are needed using different concentrations of onion, lemon, and lemon peel juice to confirm their antifungal efficacy in addition to their actual antimicrobial benefits.
... In addition, in vivo studies proved the powerful antimicrobial activity of allicin against Staphylococcus epidermidis, Leishmania promastigotes, H. pylori, and C. albicans [57]. Allicin is an unstable compound synthesized by an allinase-based enzymatic reaction [168]. Until recently, the mechanism of action of allicin has been unknown, and it is supposed that allicin is involved in the oxidation of cysteine in glutathione and proteins. ...
Ever since ancient times, Allium species have played a significant role in the human diet, in traditional medicine for the treatment of many ailments, and in officinal medicine as a supplemental ingredient. The major metabolites of alliums, as well as their antioxidant and antimicrobial properties, with an emphasis on the species most represented in the Balkan region, are discussed in this review. Due to its richness in endemic species, the Balkan region is considered the genocenter of alliums. There are 56 recorded Allium species in the Balkans, and 17 of them are endemic. The most common and well-studied Allium species in the Balkans are A. cepa (onion), A. sativum (garlic), A. ampeloprasum (leek), A. schoenoprasum (chives), A. fistulosum (Welsh onion), and A. ursinum (wild garlic or bear's garlic), which are known for their pungent taste and smell, especially noticeable in garlic and onion, and attributed to various organosulfur compounds. These plants are valued for their macronutrients and are used as desirable vegetables and spices. Additionally, phytochemicals such as organosulfur compounds, phenolics, fatty acids, and saponins are associated with the antioxidant and antimicrobial properties of these species, among many other bioactivities. All parts of the plant including the bulb, peel, clove, leaf, pseudostem, root, flower, and seed exhibit antioxidant properties in different in vitro assays. The characteristic phytocompounds that contribute to the antimicrobial activity of alliums include allicin, ajoene, allyl alcohol, and some diallyl sulfides. Nanoparticles synthesized using Allium species are also recognized for their notable antimicrobial properties.
... It is a colourless oil with low water solubility (Marchese et al. 2016). Rybak et al. (2004) observed that allicin is the greatest predominant thiosulfinate in garlic cloves representing nearly 0.4% of the overall thiosulfinates in a garlic bulb. A bulb of harvested garlic contains approximately 4-5 mg of allicin and its inimitable smell makes it measurable (Horev-Azaria et al. 2009). ...
Garlic (Allium sativum), one of the several phytogenics with its functionally bioactive compounds (allicin, allyl-methyl thiosulphonate, gamma-L-glutamyl-S-alkyl-L-cysteine and 1-propenyl allyl thiosulphonate) offers many advances for enhancement in production when supplemented in the diets of birds. A number of in vitro studies have established its potency in minimum inhibitory concentration and minimum bactericidal concentration through microdilution techniques. There is enough indication that garlic and its secondary metabolites could replicate the enormous benefits of synthetic feed additive due to its ability to inhibit gram-negative and gram-positive pathogenic bacteria thereby proliferating useful microbes in the gastrointestinal tract of chickens. Therefore, this review establishes the antibacterial activities of garlic in various processed forms/products in broiler chickens and laying hens production.
... Allicin blocks bacterial enzymes belonging to thiol groups, consequently impeding bacterial growth. This is in accordance with the statement of Boboye et al. that the mechanism of garlic inhibits bacterial growth by comprehensively inhibiting RNA, DNA, and protein synthesis of bacteria [43,44]. ...
Beef is a perishable food product susceptible to deterioration due to microbial growth. Therefore, this study aimed to ascertain how active and intelligent packaging performs by tracking the change in the quality of fresh beef stored at low temperatures. The intelligent packaging method employed indicators with solutions of Bromo Phenol Blue (BPB) and Phenol Red (PR) to monitor the change in beef quality. Additionally, active packaging used garlic extract with various concentrations at 0%, 15%, and 20% to maintain the quality of beef packaged at 10 °C temperatures. The findings illustrated that a packaging indicator label can be implemented to monitor the change in the quality of fresh beef stored at 10 °C temperatures. This was signified by a change in the indicator color from dark yellow to orange and red, fading to purple. Meanwhile, observations on active packaging demonstrated that 15% and 20% of garlic extract were the most effective approaches for preserving beef quality. The correlation level of indicator label color analysis and the effectiveness of active packaging with all beef spoilage metrics demonstrated a positive correlation in preserving quality and identifying the degree of beef damage. Therefore, these active and intelligent packaging indicators can be applied to monitor and retain the quality of packaged beef.
... On the other hand, significantly higher AC content was determined in fresh white garlic (3.37-4.60 mg/g sample), elephant garlic (0.73 mg/g) and garlic powder extracts (2.26-3.05 mg/g) also isolated with SCCO 2 [38], suggesting that AC could differ to a great extent even when same extraction techniques are utilized. ...
Citation: Krstić, M.; Teslić, N.; Bošković, P.; Obradović, D.; Zeković, Z.; Milić, A.; Pavlić, B. Isolation of Garlic Bioactives by Pressurized Liquid and Subcritical Water Extraction. Molecules 2023, 28, 369. Abstract: Garlic (Allium sativum L.) is widely used in various food products and traditional medicine. Besides unique taste and flavour, it is well known for its chemical profile and bioactive potential. The aim of this study was to apply subcritical water extraction (SWE) and pressurized liquid extraction (PLE) for the extraction of bioactive compounds from the Ranco genotype of garlic. Moreover, PLE process was optimized using response surface methodology (RSM) in order to determine effects and optimize ethanol concentration (45-75%), number of cycles (1-3), extraction time (1-3 min) and temperature (70-110 • C) for maximized total phenols content (TP) and antioxidant activity evaluated by various in vitro assays. Furthermore, temperature effect in SWE process on all responses was evaluated, while allicin content (AC), as a major organosulphur compound, was determined in all samples. Results indicated that PLE provided tremendous advantage over SWE in terms of improved yield and antioxidant activity of garlic extracts. Therefore, high-pressure processes could be used as clean and green procedures for the isolation of garlic bioactives.
... The main bioactive compound present in garlic is allicin (chemically allicin is allyl 2-propene thiosulfinate or diallylthiosulfinate). Alliin (present in fresh raw garlic) is converted to allicin by allinase enzyme which gets activated by chopping, slicing or crushing (Rybak et al. 2004). The frequency of research and experimentation on garlic is quite high for obvious reasons-its easy availability, low cost and effective anti-microbial property therefore, it is readily used as growth promoter in poultry. ...
To study the effect of garlic supplementation on gut bacterial load, histopathology and immunity of coloursynthetic broilers, 100 day old colour synthetic broiler chicks were randomly distributed into five dietary treatments.The dietary treatments for this experiment were: T1: Basal diet, T2: Basal diet + Probiotic, T3: Basal diet + Garlicpowder (0.5% of Basal diet), T4: Basal diet + Garlic powder (0.75% of Basal diet) and T5: Basal diet + Garlicpowder (1% of Basal diet). Cellular immunity, weight of lymphoid organs and histopathology were performed at35th day of experimental feeding period. The faecal bacterial load was performed at 14th and 28th day of experimentand intestinal bacterial load at 35th day. The weight of lymphoid organs, CBH response of different treated groupsdid not differ significantly. The total plate count (log10 cfu/ml) in the faeces of birds at 14th day of experiment ofgroup T1 was found to be significantly higher than that of garlic and probiotic fed groups. The total plate count andE. coli count in faeces at 28th day and intestine (35th day) of birds in garlic supplemented groups were found to besignificantly lower than the control group. The total plate count and E. coli count in the faces (28th day) andintestine (35th day) of the birds of 0.75 and 1.0% levels of garlic feeding had no significant difference between thetreated groups. From this experiment, it may be concluded that supplementation of garlic at 0.75% in coloursynthetic broiler ration reduced the gut microbial load.
... Zalepugin et al. reported an SFE for EO extraction of garlic and separating them into their individual components (Zalepugin et al. 2010). Twenty-five g of homogenized garlic homogenate initially was allowed to ferment in the air for 10 min to completely convert alliin into allicin (Rybak et al. 2004), and then it was placed into a high-pressure cell and thermo stated to the required temperatures of 40 °C (in regime 1) or 90 °C (in regime 2, for more thermostable components) and pressure of 250 bar; then, liquid CO 2 was pumped into this cell at the flow rate of 2 ml/min for 2 hours. The thermally unstable diallyl thiosulfinate or allicin was isolated from the extract at 40 °C (regime 1), and 0.25 g of allicin was produced from 25 g of homogenized garlic. ...
... Zalepugin et al. reported an SFE for EO extraction of garlic and separating them into their individual components (Zalepugin et al. 2010). Twenty-five g of homogenized garlic homogenate initially was allowed to ferment in the air for 10 min to completely convert alliin into allicin (Rybak et al. 2004), and then it was placed into a high-pressure cell and thermo stated to the required temperatures of 40 °C (in regime 1) or 90 °C (in regime 2, for more thermostable components) and pressure of 250 bar; then, liquid CO 2 was pumped into this cell at the flow rate of 2 ml/min for 2 hours. The thermally unstable diallyl thiosulfinate or allicin was isolated from the extract at 40 °C (regime 1), and 0.25 g of allicin was produced from 25 g of homogenized garlic. ...
Green chemistry was called to protect the environment and human beings from the used or wasted chemicals and solvents that represent hazards in the research laboratories. This chapter summarizes the fundamentals and applications of supercritical fluid extraction (SFE) as an alternate green and safe approach for the extraction of essential oils from different plants. At first, we explained essential oils and enumerated their sources and medicinal uses. Then, we discussed old technology for their extraction then presented the SFE approach as a green environmentally benign approach for essential oils extraction. The advantages of using SFE for essential oil extraction over traditional classical techniques were emphasized. SFE could reduce the use of petroleum solvents as well as decrease the extraction time compared to traditional extraction methods. The supercritical fluids (SFs) were characterized with a solubility like liquid and diffusivity like gas, which could dissolve different types of essential oils. Next, the effect of extraction parameter optimization on the SFE of essential oil was discussed. Finally, the taxonomy of different plant sources for essential oils and their SFE method of extraction were summarized and emphasized with many examples from the literature.KeywordsEssential oilsTaxonomyExtractionGreen solventsSupercritical fluid extractionMedicinal uses
... A study to determine the effects of fresh garlic extract (FGE) against Candida albicans ATCC 14053 demonstrated a suppression of the hyphae production and reduced expression of the gene, SIR2 (Low et al., 2008). Allicin (diallyl thiosulfinate) is a sulfur-containing organic compound that makes up a large portion (~70% w/w) of thiosulfinates found in garlic (Rybak et al., 2004;Salehi et al., 2019). Previous studies have indicated that allicin is a promising alterna Biome Journals biomescientia.com ...
Candida-associated nosocomial infections are a persistent problem which has been steadily increasing over the years. The emergence of antimicrobial resistant strains has narrowed the spectrum of effective drugs that can be utilised and indicated the need for alternative therapeutics. Garlic is a spice often studied for its unique characteristics. Most of its antimicrobial properties have been attributed to the presence of allicin, which makes up more than 70% of thiosulfinates extracted from garlic. The present study aimed to determine the effects of fresh garlic extract (FGE) towards the expression of two major biofilm genes, Flo-8 and Ndt80 produced by C. albicans that enable the morphogenesis of yeast from planktonic cells to biofilm. Minimum concentration required for FGE to inhibit C. albicans was determined through agar well and disc diffusion assay. Effect of FGE towards preformed C. albicans biofilms was evaluated at ¼× and ½× inhibitory concentrations of FGE and Amphotericin B, respectively by XTT assay. RNA from FGE-treated C. albicans was extracted, reverse transcribed and analysed by Real-Time Polymerase Chain Reaction (RT-PCR) to determine FGE effects towards the expression of Flo-8 and Ndt80. Inhibitory concentration of FGE was determined to be 100 mg/mL. Both genes appeared to be upregulated in the presence of FGE with a higher upregulation noted with Flo-8 (67.34 and 30.20-folds) when compared against Ndt80 (5.55 and 1.79-folds) at 5 mg/mL and 10 mg/mL, respectively. It is surmised that C. albicans upregulated these genes as a survival mechanism in the presence of FGE. The findings from this study indicate that FGE could inhibit C. albicans growth and biofilms. Further research is required to determine the minimum inhibitory concentration (MIC) through broth microdilution and to understand the mechanism behind this phenomenon before it can be utilised as a potential therapeutic to combat Candida-associated nosocomial infections.
... The natural-derived molecules have been produced over the last few years, increasing research on natural extracts based on herbal plants, food processing technology, or agri-food waste (Cruz et al., 2007;Moure et al., 2001). Allium sativum L. (ASL) has been utilized as an important seasoning resource from ancient times for both cuisine and health-giving purposes (Rybak et al., 2004). The ASL is a source of organosulfur compounds to prevent inflammation and chronic disorders such as cancer, obesity, and neural dysfunction (Dewi et al., 2017;Ruhee et al., 2020). ...
During garlic harvest, much husk has been generated, nearly all husk is discarded as unnecessary by‐products. However, in Korean folk remedies, Allium sativum L. husk (ASLH) extracts have been used as a reliever against type 2 diabetes mellitus (T2DM). Currently, its significant mechanisms against T2DM remain unclear. Thus, the aim of this study is to investigate the characteristics of its key signaling pathways, targets, and compounds. The compounds in ASLH were analyzed by gas chromatography–mass spectrum (GC–MS) and confirmed drug‐like compounds (DLCs) in silico. Then, protein–protein interaction (PPI) networks and signaling pathways, targets, compounds are constructed, visualized by using RStudio. Finally, we performed a molecular docking test (MDT) to identify the key mechanism(s), target(s), and compound(s) of ASLH on T2DM. A total of 23 compounds in ASLH were identified by GC–MS, and all compounds were accepted by Lipinski’s rule. The 23 compounds were associated with 521 targets and retrieved 4,736 T2DM‐related targets by Online Mendelian Inheritance in Man (OMIM) and DisGeNET. The final overlapping 87 targets were obtained between compounds–targets and T2DM‐related targets. The number of 13 signaling pathways, 33 targets, and 19 compounds of ASLH were associated with T2DM. In parallel, MDT revealed four potential compounds: (1) 9‐hexacosene, (2) 2‐(([2‐ethylhexyl]oxy)carbonyl)benzoic acid, (3) clionasterol, (4) 4‐methyl‐2‐phenylpyrimidine on PPAR signaling pathway. Overall, the four compounds from ASLH might show an anti‐T2DM synergistic effect by activating the PPAR signaling pathway or inactivating the phospholipase D signaling pathway. In this study, we suggest that ASLH might be considered a health‐promising resource from both nutraceutical and pharmaceutical perspectives.
Practical applications
Allium sativum L. husk (ASLH) has been regarded as wastes that come from garlic (Allium sativum L.). During the harvesting period of garlic, a considerable amount of ASLH is a severe problem in farm communities. Particularly, garlic bioactive compounds are well documented including organosulfur compounds. Conversely, at present, no information is available on chemical compounds of ASLH to use in health industries. Taking this matter into consideration, our analysis approach was to select drug‐like compounds (DLCs) from ASLH via GC–MS, thereby we can explore the compounds with high cell permeability. The screened compounds can be used as nutraceutical or medicinal or even cosmetical resources.
In this study, we described the significant compounds via the network pharmacology concept to uncover the pharmaceutical mechanism(s) of ASLH against T2DM. Eventually, this work provides nutraceutical or medicinal value of ASLH and suggests that ASLH might be used as an upcycling resource to relieve T2DM.
... Garlic (Allium sativum L.) and its derived products have been widely used for culinary and medicinal purposes in many cultures and civilizations [17]. Garlic extract has protective effects in PAH, but its molecular mechanism is unknown [18]. ...
Pulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling. Recent evidence supports that inflammation plays a key role in triggering and maintaining pulmonary vascular remodeling. Recent studies have shown that garlic extract has protective effects in PAH, but the precise role of allicin, a compound derived from garlic, is unknown. Thus, we used allicin to evaluate its effects on inflammation and fibrosis in PAH. Male Wistar rats were divided into three groups: control (CON), monocrotaline (60 mg/kg) (MCT), and MCT plus allicin (16 mg/kg/oral gavage) (MCT + A). Right ventricle (RV) hypertrophy and pulmonary arterial medial wall thickness were determined. IL-1β, IL-6, TNF-α, NFкB p65, Iкβ, TGF-β, and α-SMA were determined by Western blot analysis. In addition, TNF-α and TGF-β were determined by immunohistochemistry, and miR-21-5p and mRNA expressions of Cd68, Bmpr2, and Smad5 were determined by RT-qPCR. Results: Allicin prevented increases in vessel wall thickness due to TNF-α, IL-6, IL-1β, and Cd68 in the lung. In addition, TGF-β, α-SMA, and fibrosis were lower in the MCT + A group compared with the MCT group. In the RV, allicin prevented increases in TNF-α, IL-6, and TGF-b. These observations suggest that, through the modulation of proinflammatory and profibrotic markers in the lung and heart, allicin delays the progression of PAH.
... In one fresh crushed garlic clove there is aproximately 4-5 mg of allicin. Allicin is an unstable compound and it is rapidly degraded under the influence of temperature and pH (43,44). Acidic solutions (e.g. ...
H. pylori is a widespread pathogen, being the main culprit behind gastric and peptic ulcers with possible implications in the development of gastric cancers. In vitro studies have shown that ellagic acid and derivatives present in significant amounts in fruits and leaves have moderate bactericidal effects on H. pylori, while resveratrol was noted to inhibit urease enzyme as high as 90% in different strains of H. pylori. Quercetin seems to inhibit pathogen’s VacA enzyme and kaempferol may prevent translocation of CagA, both phytochemicals being found in significant amounts in berries. In one clinical study, allicin was found to act synergically with standard antibiotic regimens. Although in vitro results seem promising, in vivo studies did not underline significant clinical benefits of phytochemicals compared to standard therapy. Therefore, further studies are needed to accurately estimate any clinical benefit of dietary phytochemicals in H. pylori infection.
... The SAM calibration curves of the recovered standard enable the determination of the intersection of a straight line with the x-axis, which is the value used for calculation of the targeted analyte concentration. Additionally, the influence of interferences on the results is eliminated by applying chromatography as a separation method [41][42][43][44]. ...
About 70 million people suffer from epilepsy—a chronic neurodegenerative disease. In most cases, the cause of the disease is unknown, but epilepsy can also develop as the result of a stroke, trauma to the brain, or the use of psychotropic substances. The treatment of epilepsy is mainly based on the administration of anticonvulsants, which the patient must most often use throughout their life. Despite significant progress in research on antiepileptic drugs, about 30% of patients still have drug-resistant epilepsy, which is insensitive to pharmacotherapy used so far. In our recent studies, we have shown that 4-alkyl-5-aryl-1,2,4-triazole-3-thiones act on the voltage-gated sodium channels and exhibit anticonvulsant activity in an MES (maximal electroshock-induced seizure) and 6Hz test in mice. Previous studies have shown their beneficial toxic and pharmacological profile, but their effect on a living organism during chronic use is still unknown. In the presented study, on the basis of the previously conducted tests and the PAMPA (parallel artificial membrane permeability assay) BBB (blood–brain barrier) test, we selected one 1,2,4-triazole-3-thione derivative—TP-315—for further studies aimed at assessing the impact of its chronic use on a living organism. After long-term administration of TP-315 to Albino Swiss mice, its effect on the functional parameters of internal organs was assessed by performing biochemical, morphological, and histopathological examinations. It was also determined whether the tested compound inhibits selected isoforms of the CYP450 enzyme system. On the basis of the conducted tests, it was found that TP-315 does not show nephrotoxic nor hepatotoxic effects and does not cause changes in hematological parameters. In vitro tests showed that TP-315 did not inhibit CYP2B6, CYP2D6, CYP3A4, or CYP3A5 enzymes at the concentration found in the serum of mice subjected to long-term exposure to this compound.
... most abundant thiosulfinate (70% w/w) found in fresh garlic is an unstable volatile molecule produced by allinase based enzymatic reaction from its precursor amino acid Rybak et al., 2004). Ajoene, on the other hand, an organosulfur compound found in garlic, is a molecule that is significantly stable and biologically active and is documented for its deep antimicrobial activity which specifically inhibits quorum sensing in pathogenic bacteria such as Pseudomonas aeruginosa (Jakobsen et al., 2012;Silva et al., 2018). ...
Recent development in the synthesis of nanoparticles relies on the use of green chemistry with safe, biocompatible materials to manufacture composites, structures, and formulations based on nano for specific applications. The basic goal of green nanoparticle synthesis is to make use of the element's specific physicochemical and biological properties by linking bioactive from prokaryotes and eukaryotes for applications in various basic and applied science fields. Biogenic methods have the potential to provide advanced strategies for surface/material modification in the increasing carbonaceous materials market. Garlic is an extensively studied herb known for possessing a wide variety of bioactive. The major proportion of garlic bioactive is organosulfur or thiol based organic compounds that have numerous biological and therapeutic activities and thus target biogenic nanocomponents and formulations for synthesis. There is, however, very scant literature on its use in the agriculture sector. The present review focuses on the synthesis of garlic related nanoparticles and their applications across various scientific fields, and their potential environmental implications when used in agriculture.
... Both of which marks the concentration of garlic between 60 -80 % of thiosulphonates present in garlic. 15,16 Study done by Yan Liang et al. 17 and Michael E. Ryback et al. 18 high performance liquid chromatography was determined as best method of allicin determination along with its presence between 70 -80 % of thiosulphonates in garlic. Lawson et al. 19 and Harris et al. 20 in their respective studies depicted the importance of allicin as antimicrobial, antiinflammatory, anticancer and antioxidant. ...
... The processing of garlic bulb could rise several chemical modifications to the formation of thiosulfinates, in which the precursor compound alliin is transformed into allicin (diallyl thiosulfinate) by enzymatic action. Allicin is the most important bioactive compound in garlic due to its broad functional activity and high concentrations, however, allicin along with alliinase, which catalyses the conversion of alliin to allicin, are thermolabile (Ratti, Araya-Farias, Mendez-Lagunas, & Makhlouf, 2007); thus the latter decomposes within a few hours to form more stable sulfur compounds that have reduced activity (Lawson & Hughes, 1992;Rybak, Calvey, & Harnly, 2004). ...
Rabbit burgers were evaluated for fatty acids profile, oxidative status, antioxidant potential and sensory during storage time of seven days at 4 °C. The aim of the research study was to evaluate if a common culinary spice as garlic could overcome the controversy effects of salt (mostly related to a pro-oxidant effect). Therefore, four formulations were made: only meat (control, C) meat added with garlic powder at 0.25% (G), meat added with salt at 1.00% (S) and meat added with garlic powder (0.25%) and salt (1.00%) (GS). As results, it was highlighted that garlic powder was not capable to reduce significantly the negative effect related to the salt addition. Salt induced different modifications to burgers leading to a more liked product due to its properties to enhance sensory characteristics, on the other hand, induced different oxidation processes that could decrease the nutritional value. Further studies are needed to better elucidate if different garlic products/concentrations could apport higher beneficial effects.
... The highly expressed gene in clove was alliinase having about 12-fold higher expression than in leaf tissue. Alliinase is implicated in the conversion of alliin to allicin, which is an organosulfur metabolite [50][51][52][53]. Other highly expressed genes in clove that are the candidates for the organosulfur metabolism include plant cysteine oxidase 2-like, cysteine protease XCP1, serine carboxypeptidase-like 45, flavonol sulfotransferase-like, caffeoyl-CoA O-methyltransferase-like, glutathione S-transferase T1 and glutathione gamma-glutamylcysteinyltransferase 1-like isoform X1. ...
Snow Mountain Garlic grows in the high altitudes of the Himalayas under low temperature conditions. It contains various bioactive compounds whose metabolic pathways have not been worked out at genomic level. The present work is the first report on the transcriptome sequencing of this plant. >43 million paired-end reads (301 × 2) were generated using Illumina Miseq sequencing technology. Assembling of the sequencing data resulted in 326,785 transcripts. Differentially expressed genes between the clove and leaf tissues were identified and characterized. Besides, greater emphasis was laid on the genes, which were highly expressed in clove since the latter is assumed to contain high content of the bioactive compounds. Further analysis led to the identification of the genes plausibly involved in the organosulfur metabolism. We also identified several simple sequence repeats and single nucleotide polymorphism. These constitute valuable genetic resource for research and further genetic improvement of the plant.
... It is thought to be one of the main bioactive organosulfur compounds synthesized in Allium species, and responsible for its typical pungent smell and taste. In fact, allicin is the most abundant thiosulfinate in fresh garlic, typically accounting for 70% (w/w) of the total thiosulfinates (approximately 0.4% by fresh mass) (Rybak, Calvey, & Harnly, 2004). About 4-5 mg of allicin are found in one clove of fresh garlic and its presence is easily detectable due to its unique odor (Horev-Azaria et al., 2009). ...
Background: Allicin is an organosulfur and defensive compound found in garlic (Allium sativum L.) and other Allium species. Its unique odor is easily detectable, and its effects on human health have been studied since ancient times. Scope and approach: In this compressive review we report the presence of allicin in different Allium species, their biosynthesis, pharmacokinetics, absorption, and safety profile. Among the main allicin applications highlight its antimicrobial and antiparasitic properties, reviewed in the present work from in vitro evidence and in vivo studies. Finally, special attention was also given to the allicin state of the art in human health, including in vitro and in vivo assays, and clinical trials, on antioxidant, anticancer, antidiabetic and immunomodulatory effects, besides to its contribution as a cardioprotective agent. Key findings and conclusions: The promising capacity of allicin to interact with thiol groups seems to be directly related to its antimicrobial potential, showing both antibacterial and antifungal activities. Allicin also displayed an interesting potential in the prevention and treatment of several diseases including diabetes mellitus, cardiovascular disease, and cancer. Indeed, its antioxidant and immunomodulatory effects are some of the mechanisms that may explain their biological activities. Future applications should be directed to allicin pharmaceutical formulation, its delivery and its compatibility with food matrices and other drugs due to allicin biosynthesis, instability, reactivity, and volatility.
... Another reason for the significant loss in allicin was the self-decomposition of allicin under high temperature. Allicin is an unstable and thermolabile compound that easily decomposed to more stable substance including sulfur-containing compounds (Jansen, Müller, & Knobloch, 1989;Rybak, Calvey, & Harnly, 2004). Allicin even broke down into diallyl disulfides and sulfur dioxides during 20 hr at the room temperature (Rivlin, Budof, & Amagase, 2006). ...
Blanching is a feasible and effective method widely applied to prevent greening in garlic puree. However, this processing may cause the physical and chemical changes in garlic puree. Therefore, an investigation was carried out to systematically explore the effects of hot water blanching on enzyme inactivation (alliinase and γ‐glutamyl transpeptidase, GGT), discoloration, allicin degradation, and antioxidant capacity of garlic puree. The results showed that the inactivation of alliinase and GGT was strongly dependent on blanching temperature and time. Garlic puree turned into white when blanched at 80°C for 5 min or at 90°C for 4 min, with a* value of −3.24 ± 0.11, −2.80 ± 0.43, respectively. The inactivation kinetics of alliinase and GGT followed a first‐order reaction, as well as the kinetic of green discoloration. However, allicin content was dropped by 71, 80, and 85% after blanching for 5 min at 70, 80, and 90°C, respectively. A decline in the antioxidant capacity of garlic treated by blanching was also observed. The current findings indicated that blanching could contribute to inhabit garlic greening but had negative effects on the nutritional ingredients of garlic puree.
Practical applications
Garlic is prone to greening when processed into garlic puree, garlic juice and other products. The occurrence of greening seriously hindered the further processing of garlic. Blanching is an effective and feasible method to prevent greening in garlic puree. In this study, the effects of blanching on enzyme inactivation, color changes, allicin degradation and antioxidant capacity of garlic puree were studied. This study provides a theoretical basis for the deep processing of garlic.
... In case of the diclofenac sodium salt (Fig. 5.7c), only a single characteristic ion peak is observed, which is identified as the ammoniated monomer of the active ingredient As expected, the direct analysis of a freshly peeled garlic clove (Fig. 5.8b) immediately reveals the presence of allicin, the predominant organosulfur compound in garlic (3.2-4.8 mg g −1 , < 30 µmol). [317] After tissue damage occurs, the enzyme alliinase converts the alliin to allicin. [318] The tion schemes, such as the PADI source, additional fragmentation processes of the target molecule allicin are not observed. ...
Eine der bedeutendsten technischen Errungenschaften des letzten Jahrhunderts beinhaltet zweifelsfrei die Erfindung des Lasers. Bereits wenige Jahrzehnte nach seiner ersten technischen Umsetzung ist er heute aus so unterschiedlichen Anwendungsbereichen wie der Mess- und Regeltechnik, der Unterhaltungselektronik, sowie der industriellen Fertigung und Materialbearbeitung nicht mehr wegzudenken. Die analytische Chemie bildet hier keine Ausnahme. Die Möglichkeit mittels Laserstrahlung sowohl räumlich als auch zeitlich definiert einen maßgeschneiderten Energieeintrag in Materialsysteme vorzunehmen, wird heute umfangreich in diversen Analyseverfahren eingesetzt. Ein Meilenstein auf dem Gebiet der Laserentwicklung stellt die Einführung diodengepumpter Festkörperlaser (DPSS) dar. Diese neuartige Lasergeneration vereint die Vorteile einer begünstigten Energiebilanz durch resonante Anregung im Lasermedium mit einer erhöhten Flexibilität der zeitlichen Modulation der Laserausgangsleistung. Während DPSS Laser auf dem Gebiet der Materialbearbeitung bereits die Hälfte des Marktanteils ausmachen, finden sie bislang in den analytischen Wissenschaften nur wenig Verbreitung. Auch hier könnten die inhärenten Vorteile von DPSS Lasern bezüglich Konversionseffizienz, Stabilität, Flexibilität und Strahlprofil maßgeblich zu einer Optimierung relevanter Teilschritte beitragen. Die vorliegende Arbeit schließt diese Lücke, indem sie die Anwendbarkeit eines modernen DPSS Lasers für solch unterschiedliche Aufgaben wie der Laserablation, der Raman-Spektroskopie, der atomaren und molekularen Emissionsspektroskopie, bis hin zur Erzeugung eines neuartigen quasi-kontinuierlichen, luftgetragenen Plasmas für die Atmosphärendruck-Ionisation untersucht. In allen Studien konnten die Verbesserungen der jeweiligen analytischen Verfahren auf die Eigenschaften des verwendeten Lasers zurückgeführt werden.
In spite of significant advancements in diagnosis and treatment, cancer remains one of the major threats to human health due to its ability to cause disease with high morbidity and mortality. A multifactorial and multitargeted approach is required towards intervention of the multitude of signaling pathways associated with carcinogenesis inclusive of angiogenesis and metastasis. In this context, plants provide an immense source of phytotherapeutics that show great promise as anticancer drugs. There is increasing epidemiological data indicating that diets rich in vegetables and fruits could decrease the risks of certain cancers. Several studies have proved that natural plant polyphenols, such as flavonoids, lignans, phenolic acids, alkaloids, phenylpropanoids, isoprenoids, terpenes, and stilbenes, could be used in anticancer prophylaxis and therapeutics by recruitment of mechanisms inclusive of antioxidant and anti-inflammatory activities and modulation of several molecular events associated with carcinogenesis. The current review discusses the anticancer activities of principal phytochemicals with focus on signaling circuits towards targeted cancer prophylaxis and therapy. Also addressed are plant-derived anti-cancer vaccines, nanoparticles, monoclonal antibodies, and immunotherapies. This review article brings to light the importance of plants and plant-based platforms as invaluable, low-cost sources of anti-cancer molecules of particular applicability in resource-poor developing countries.
Bentham Briefs in Biomedicine and Pharmacotherapy showcases the latest developments and techniques in the fields of pharmacology and healthcare, presenting them in distinctive volumes. Each volume offers a concise, focused overview of subjects, authored by experts in the field. The book series serves as an anthology for graduate students and researchers in pharmacology and life sciences, as well as medical professionals seeking specialization for research-related projects.
The second volume, Botanicals and Natural Bioactives: Prevention and Treatment of Diseases, discusses the medicinal applications of natural bioactives in the treatment of a variety of physiological disorders, including cardiovascular diseases, neurological dysfunctions, infectious diseases, age-related diseases, and cancer. The volume has eight chapters on disease treatment and preventative measures, with contributions from more than twenty experts. Readers will comprehend the niche utilization of botanicals and natural bioactives as medicinal agents for a variety of ailments. Overall, the chapters dwell on the chemosensory features of nutritious foods to avoid non-communicable diseases and the role of immunomodulating natural products and botanicals in the prevention and treatment of skin diseases, aging, inflammation, cancer, parasitic infections in the bloodstream, neurodegenerative diseases, osteoporosis, coronary heart disease, and autoimmune disorders. The variety of topics covered in this book makes it an excellent resource for a wide audience interested in phytomedicine.
Synthetic insecticides, which are commonly applied on crops nowadays, often contain compounds that have toxic effects on humans, which can result in poisoning or death. To find potential alternatives to synthetic insecticides that are safer to humans and effective against pests, this study investigates the toxic effects of allicin on insects as a potential alternative to synthetic insecticides. Allicin solutions of different concentrations are obtained from fresh garlic cloves, and mealworms and crickets are made to come into contact with allicin solution through the skin. In doing so, this study determines the relationship between the concentration of allicin solution and the toxic effects of allicin solution on insects. The toxic effects of allicin solutions of different concentrations on insects are also compared with the toxic effects of synthetic insecticides on insects. Through analysis of the results, this study confirms that allicin has toxic effects on insects. By using trend lines, it can be estimated that increasing the concentration of allicin solution further to greater than about 6.250 g dm−3 no longer results in a significant increase in the toxic effects of allicin solution on insects. It is also noted that when the concentration of allicin solution is about 7.500 g dm−3, the toxic effects of allicin solution on insects are comparable to the toxic effects of synthetic insecticides on insects. Hence, this study confirms the potential of allicin to be used as a potential alternative to synthetic insecticides that is safer to humans and effective against pests.
Antibiotics and zinc oxide restrictions encourage the search for alternatives to combat intestinal pathogens, including enterotoxigenic Escherichia coli (ETEC), a major cause of postweaning diarrhea (PWD) in pigs. PWD causes important economic losses for conventional and organic farming. This study investigated the effect of dietary supplementation with garlic and apple pomace or blackcurrant on infection indicators and the fecal microbiota of organic-raised piglets challenged with ETEC-F18. For 21 days, 32 piglets (7-weeks-old) were randomly assigned to one of four groups: non-challenge (NC); ETEC-challenged (PC); ETEC-challenged receiving garlic and apple pomace (3 + 3%; GA); ETEC-challenged receiving garlic and blackcurrant (3 + 3%; GB). ETEC-F18 was administered (8 mL; 10⁹ CFU/ml) on days 1 and 2 postweaning. The 1st week, PC had lower average daily gain than those in the NC, GA, and GB groups (P < 0.05). NC pigs showed neither ETEC-F18 shedding nor signs of diarrhea. The PC group had higher diarrhea incidence and lower fecal dry matter than NC (≈5–10 days; 95% sEBCI). The GA and GB groups showed reduced ETEC-F18 and fedA gene shedding, higher fecal dry matter, and lower diarrhea incidence than the PC (≈5–9 days; 95% sEBCI). The NC, GA, and GB had normal hematology values during most of the study, whereas the PC had increased (P < 0.05) red blood cells, hemoglobin, and hematocrit on day 7. Haptoglobin and pig-MAP increased in all groups, peaking on day 7, but PC showed the greatest increase (P < 0.05). The fecal microbiota of PC pigs had reduced α-diversity (day 7; P < 0.05) and higher volatility (days 3–14; P < 0.05). Escherichia, Campylobacter, and Erysipelothrix were more abundant in the PC than in the NC, GB, and GA groups (log2FC > 2; P < 0.05), whereas Catenibacterium, Dialister, and Mitsoukella were more abundant in the NC, GB, and GA than in the PC group (log2FC > 2; P < 0.05). Prevotella and Lactobacillus were more abundant in the GB group (log2FC > 2, P < 0.05). In conclusion, dietary supplementation of GA and GB limited ETEC proliferation, reduced PWD, and beneficially impacted the fecal microbiota's diversity, composition, and stability.
Diabetes mellitus (DM), caused by either insulin resistance or abnormal insulin secretion, or both, continues to be one of the most prevalent endocrine disorders in the world. In fact, DM is the third most common cause of mortality and morbidity, next only to cancer and cardiovascular disorders. About 463 million people were said to have suffered from DM around the world in 2019. This number is soon to reach 548 million by the end of 2020 and is projected to be 700 million by 2045. Several studies have indicated that DM is found to be more prevalent in high-income countries and urban areas than in the rest. Typically characterized by multiple etiologies and a persistent state of hyperglycemia, DM is prone to cause multiple disorders, affecting several organs of the body. Its treatment, thus, proves to be quite tricky, requiring a multimodal approach. For instance, in order to manage the glucose levels of a DM patient, it is crucial to identify a whole host of individual factors that contribute toward the defective glycemic index. Of the many ways of effectively controlling and managing DM, several plant species and plant-based compounds play a pivotal role. It is against this backdrop that a review was conducted to ascertain the performance and characteristics of several plant-based bioactive compounds in the treatment of DM. It was found that the plant-based bioactive compounds exhibit a higher level of antidiabetic activity than that of non-plant-based hypoglycemic drugs. A compendious account of the review is provided here. It may be noted that though the review indicates the high level of antidiabetic activity of plant-based drugs such as polyphenols, alkaloids, flavonoids, coumarins, and terpenoids, attributing their derivatives to the corresponding plant structures, it does not include any discussion on structure-related activity.
Nature offers us spices, which are a significant part of healthy and nutritious foods. The presence of abundant bioactive compounds in these spices makes them interesting from a scientific and health perspective. Extracts obtained from spice materials possess many health benefits and are rich sources of antioxidants, which suppress reactive oxygen species.
Spice Bioactive Compounds: Properties, Applications, and Health Benefits collects such information together in one book, presenting all necessary features related to spices and their properties. Exploring the most recent research related to the extraction, isolation, encapsulation, identification, and characterization of bioactive compounds present in spices, this book also covers the health element of spices and its utilization as a treatment for various disorders.
Key Features:
Discusses about 14 different spices and their salient features
Presents the novel technologies used in the extraction, isolation, and identification of bioactive compounds from spices
Explores the utilization of spices for culinary use in food
Industries such as the food and pharmaceutical industries have great interest in the use of bioactive compounds for the production of drugs and functional foods. Written by experts in their field, this book will be useful to anyone in either industry, as well as those who have an interest in the use of such bioactive compounds for the production of drugs and functional foods.
This researchpaper includes the incorporation of Alliin at various energy levels and angles With Metformin using Gaussian 09 and Gaussian view 06. Two computers were used in this work. Samples were generated to draw, integrate, simulate and measure the value of the potential energy surface by means of which the lowest energy value was (-1227.408au). The best correlation compound was achieved between Alliin and Metformin through the low energy values where the best place for metformin to bind was through (CH2-). This is considered to be very useful for the industrial application of drugs. This level of calculation was used for physical and quantum properties such as total energy, HOMO and LUMO orbitals energies, and power gap. Besides, the calculation of FT-IR spectra in the range 400-4000 cm-1 was calculated in addition to the essential vibrational frequencies and the intensity of the vibrational bands. Moreover, the chemical displacement of the 1H and 13C NMR of the compound in the ground state was studied.
The interaction of allicin with bovine serum albumin (BSA) and the effect of allicin binding on the structure of protein were investigated. The BSA fluorescence displayed decreased fluorescence strength after binding with allicin, which quenched BSA fluorescence in a concentration-dependent manner. The number of binding sites and binding constants were measured by fluorescent quenching method. The result of reverse phase HPLC showed that the peak of BSA shifted to higher retention time, which indicated that allicin had bound to BSA. 88.4% of total free thiol groups of BSA have bound to allicin at the allicin/BSA molar ratio of 0.1. Allicin could destabilize the secondary and tertiary structure of BSA. At the allicin/BSA ratio of 0.1, the BSA's circular dichroism spectrum showed that allicin caused a decrease of α-helix content and a significant increase of the β-sheet content (p < 0.05). Changes in surface hydrophobicity indicated that more hydrophobic groups were exposed due to the action of allicin. These results provide important insight into the study of prevailing role of protein in drug pharmacokinetics and pharmacodynamics.
In this paper, new oral beads were developed for poultry applications using garlic nanoparticles (NPs). The NPs were synthesized using water in oil micro-emulsion method and it was confirmed using energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The biocompatibility was evaluated by using the chicken blood, chicken intestinal cell line and the results indicated that the particles are highly safe. The oral beads were formulated using hydroxyl propyl methyl cellulose phthalate as polymer protective layer and specifically dissolved in pH 6.5 and released the NPs at the intestine. To study their impacts, the chickens were fed with beads starting day 3 after hatching, and their weight was recorded. To study the anti-parasitic effect, the chickens were challenged with Eimeria species. The active treatments with oral beads effectively cure the intestinal damages triggered by the Eimeria species and improved the chicken weight. The prophylactic treatment 100% protects chicken against Eimeria infection and increased the body weight.
There is an enormous demand in the food industry to shift toward natural flavors. However, most flavor molecules are significantly unstable outside their original sources. Moreover, limited studies are focused on the flavor formation mechanisms, regeneration methods, and stability, which could help facilitate this replacement by establishing a link between food processing conditions and flavor generation.
This scoping review summarizes major findings related to the identification of garlic, onion, and chili pepper flavors and their precursor molecules, formation mechanisms, generation of flavors and precursors, characterization methods, and precursor stability under thermal food processing conditions. The findings confirmed that the allium flavors could be generated by alliin and isoalliin precursors through thermal processing. Also, the literature lacks detailed knowledge about chili pepper flavor’s precursors, and only capsaicinoids have been reported as a thermally stable chili pepper flavor.
Although numerous studies have focused on this area, there is still a lack of detailed applicable knowledge. Future investigations can be framed into (1) Development of efficient methods to generate flavors during food processing; (2) Improvement of flavors’ stability; (3) Understanding the interactions of flavors and their precursors with other food ingredients and additives; and (4) Characterization of the organoleptic properties of flavors.
Garlic or Allium sativum have a lot of health benefits, especially on reducing blood pressure, fighting against the common cold and improve cholesterol in which lower the risk of heart attack problem. It is considered as one of the best disease preventive foods as it exhibits high biological activity when the fresh garlic is cut or crushed that attributed to sulfur compounds and thiosulphates. One of the active compounds in thiosulphates group namely allicin. Generally, allicin is not presence in garlic and to produce the allicin, enzyme alliinase is needed to activate with the presence of water. The common technique to extract allicin is using solvent extraction, UAE, PLE and SCCO2. The drawbacks of using these techniques including the use of organic solvent, long extraction time, and required two type of processes which is enzymatic process and extraction process. SWE is introduced to enhance the conventional process with high purity of product, water poses a mimic the properties of organic solvent and the enzymatic and extraction process undergo in one system. Therefore, this mini review aims to discuss the allicin in garlic, the literature on allicin extraction, the principle of SWE, and the application of SWE on allicin extraction.
Cancer is one of the main causes of death globally and considered as a major challenge for the public health system. The high toxicity and the lack of selectivity of conventional anticancer therapies make the search for alternative treatments a priority. In this review, we describe the main plant-derived natural products used as anticancer agents. Natural sources, extraction methods, anticancer mechanisms, clinical studies, and pharmaceutical formulation are discussed in this review. Studies covered by this review should provide a solid foundation for researchers and physicians to enhance basic and clinical research on developing alternative anticancer therapies.
Effects of different levels of choline and garlic powder on performance, liver health and immune response
in broiler chickens were evaluated in this study. A factorial experiment with 2 dietary choline levels (the
recommended level in Ross 308 broiler guidelines and 25 % less than the recommendation) and 3 dietary
garlic powder levels (0, 5 or 10 g/kg diet) was conducted using Ross 308 broiler chickens. Four hundred
eighty 1-d-old Ross 308 broiler chickens were randomly divided into 6 dietary treatments, each containing
4 replicate pens, with 20 birds each. During the finisher phase (d 25 to 42), dietary supplementation with 5
and 10 g/kg of garlic powder increased feed intake. At finisher phase and the whole experimental period,
dietary supplementation with 10 g/kg of garlic powder improved the daily weight gain. During the finisher
phase and the whole experimental period, the daily weight gain of birds fed low choline diets was less than
that of birds fed recommended choline level. During the finisher phase and the whole experimental period,
dietary choline deficiency increased feed conversion ratio. Choline deficiency decreased serum IgM level,
and IgM concentration was higher in chicks fed diet with 5 g/kg garlic powder. However, dietary garlic
powder at 10 g/kg level increased the total white blood cells and reduced the heterophyles numbers. Diets
deficient in choline and also 10 g/kg dietary garlic powder increased the liver fat deposits. The liver Creatine phosphokinase (CPK) enzyme levels in the serum of chicks fed the choline-deficient diets were higher
compared to birds fed the diets with recommended choline level. Consumption of garlic powder at 10 g/kg
level, lowered serum CPK enzyme levels compared with the diets containing zero or 5 g/kg garlic powder.
Choline deficiency and also dietary garlic regardless of its dosage were reduced the levels of serum triglycerides and very low density lipoproteins (VLDL). However, serum HDL were decreased in chickens fed 5
g/kg garlic powder compared with those fed garlic free diets. The findings of this study suggest that the
effect of garlic powder in addressing the adverse effects caused by deficiency of choline are not through
lipid metabolism improvement and more likely are due to the beneficial effects of garlic on increased feed
intake , which increased choline intake and improved immune system function.
Ajoene is a sulfur-containing compound in garlic, which accounts for pharmaceutical quality. The aim of this study was to investigate the influence of sulfur supply on the ajoene content of garlic and to evaluate the significance for crop quality. Garlic plants were grown hydroponically in a growth chamber under artificial lighting for two months at air temperature of 25/21°C (light/dark), relative humidity of 75/90% (light/dark), a photosynthetic photon flux density of 450 μmol m-2 s-1, and a photoperiod of 12 h d-1. Sulfur was supplied as K2SO4 at 2.1, 4.1 and 8.2 mg L-1. No K2SO4 was added to the control treatment. The fresh and dry biomass, as well as ajoene content was determined after harvest. The significantly lowest ajoene content was observed in the control treatment as compared to sulfur treatments. The present study showed that sulfur fertilization could be useful to improve phytomedicinal components in garlic plants.
A photochemical decomposition of organosulfur compounds (OSCs), such as allyl methyl sulfide (AMS), dimethyl disulfide (DMDS) and diallyl sulfide (DAS), was performed by oxalate-containing photo-Fenton reaction. The residual concentration ratio of the OSCs was in a descending order: AMS < DMDS ≅ DAS. The AMS of 1.45 μg L⁻¹ was approximately 90 % degraded by a photo-Fenton reaction in 120 min with a hydrogen peroxide concentration of 50 mmol L⁻¹, a sodium oxalate concentration of 3 mmol L⁻¹ and a ferric chloride concentration of 0.7 mmol L⁻¹ under ultraviolet light irradiation. In this reaction, the OSCs in the gas phase are considered to be dissolved in the liquid phase and decomposed by •OH from a photo-Fenton reaction at the water interface, whose reactivity would depend on the solubility in water and the chemical structure. This method could be useful for the decomposition of potent odorants of OSCs in a real environment.
Allicin (diallylthiosulfinate) is the main biologically active component of freshly crushed garlic cloves. It is produced upon the interaction of the nonprotein amino acid alliin with the enzyme alliinase (alliin lyase, EC 4.4.1.4). A simple and rapid spectrophotometric procedure for determination of allicin and alliinase activity, based on the reaction between 2-nitro-5-thiobenzoate (NTB) and allicin, is described. NTB reacts with the activated disulfide bond --S(O)-S--; of allicin, forming the mixed-disulfide allylmercapto-NTB, as characterized by NMR. The method can be used for determination of allicin and total thiosulfinates in garlic preparations and garlic-derived products. The method was applied for determination of pure alliinase activity and for the activity of the enzyme in crude garlic extracts.
Various components of garlic and aged garlic extract, including allicin, S-allylcysteine (SAC) and volatile metabolites of allicin were determined in breath, plasma and simulated gastric fluids by HPLC, gas chromatography (GC) or HPLC- and GC-mass spectrometry (MS). Data indicate that allicin decomposes in stomach acid to release allyl sulfides, disulfides and other volatiles that are postulated to be metabolized by glutathione and/or S-adenosylmethionine to form allyl methyl sulfide. SAC can be absorbed by the body and can be determined in plasma by HPLC or HPLC-MS using atmospheric pressure chemical ionization (APCI)-MS.
Although garlic has been used for its medicinal properties for thousands of years, investigations into its mode of action are relatively recent. Garlic has a wide spectrum of actions; not only is it antibacterial, antiviral, antifungal and antiprotozoal, but it also has beneficial effects on the cardiovascular and immune systems. Resurgence in the use of natural herbal alternatives has brought the use of medicinal plants to the forefront of pharmacological investigations, and many new drugs are being discovered. This review aims to address the historical use of garlic and its sulfur chemistry, and to provide a basis for further research into its antimicrobial properties.
Allicin (diallylthiosulfinate) is the best known active compound of garlic. It is generated upon the interaction of the nonprotein amino acid alliin with the enzyme alliinase (alliin lyase, EC 4.4.1.4). Previously, we described a simple spectrophotometric assay for the determination of allicin and alliinase activity, based on the reaction between 2-nitro-5-thiobenzoate (NTB) and allicin. This reagent is not commercially available and must be synthesized. In this paper we describe the quantitative analysis of alliin and allicin, as well as of alliinase activity with 4-mercaptopyridine (4-MP), a commercially available chromogenic thiol. The assay is based on the reaction of 4-MP (lambda(max)=324nm) with the activated disulfide bond of thiosulfinates -S(O)-S-, forming the mixed disulfide, 4-allylmercaptothiopyridine, which has no absorbance at this region. The structure of 4-allylmercaptothiopyridine was confirmed by mass spectrometry. The method was used for the determination of alliin and allicin concentrations in their pure form as well as of alliin and total thiosulfinates concentrations in crude garlic preparations and garlic-derived products, at micromolar concentrations. The 4-MP assay is an easy, sensitive, fast, noncostly, and highly efficient throughput assay of allicin, alliin, and alliinase in garlic preparations.
Alliin and allicin in garlic and their products are determined simultaneously by ion-pair reversed-phase liquid chromatography (LC) with diode array UV detection. Alliin is extracted from fresh garlic, purified by ion-exchange chromatography, and applied as external standard. Allicin is generated enzymatically from alliin, confirmed by LC, and applied as external standard. Compounds are extracted from samples with water and chromatographed on an octadecylsilane column with gradient elution from 0.01M phosphate buffer (pH 2.5) with 5 mM heptanesulfonic acid (A) to 0.01M phosphate buffer (pH 2.5)-acetonitrile (1 + 1; B). The method can be used to analyze fresh garlic, spices, garlic preparations, and health foods.
Supercritical fluid technologies are viable alternatives for the extraction and analysis of natural products because of the heightened awareness of the cost and safety hazards associated with the use and disposal of conventional organic solvents. Supercritical CO2 (SC-CO2) is of particular interest to the food industry. Because of its low critical temperature, SC-CO2 extraction can provide an accurate representation of the taste, color and odor of naturally occurring materials found in spices, flavors and foods. The application of supercritical fluid extraction technology to the analysis and/or production of spice and flavor extracts is discussed. The use of the technology in the extraction of organosulfur compounds found in Allium species is emphasized.
Numerous clinical trials with garlic cloves and standardized garlic powder tablets leave little doubt that modest amounts of garlic have significant cardiovascular effects by reducing serum cholesterol, blood pressure, and platelet aggregation. Epidemiological and animal studies strongly indicate significant anticancer effects, particularly for the intestinal tract. Furthermore, its intestinal and topical antimicrobial activities have been its longest recognized effects. Identification of the compounds essential to the activity of garlic, mostly ascribed to its high content of sulfur compounds, has only been partially resolved. So far, the thiosulfinates, of which allicin is 70-80%, are the only compounds with reasonably proven activity at levels representing normal amounts of garlic consumption. They are clearly responsible for the antimicrobial effects. Several evidences also indicate that they are essential to most of the hypolipidemic, antithrombotic, antioxidant, and hypoglycemic effects of garlic, and for some of its anticancer effects. However, because the thiosulfinates are rapidly metabolized and since their active metabolites have not yet been identified, little is known about their mechanism of action. The compounds responsible for the hypotensive effects and much of the anticancer and immune effects of garlic remain unknown. Until they are known, it is best to consume garlic in whole form, fresh or dried.
Numerous clinical trials with garlic cloves and standardized garlic powder tablets leave little doubt that modest amounts of garlic have significant cardiovascular effects by reducing serum cholesterol, blood pressure, and platelet aggregation. Epidemiological and animal studies strongly indicate significant anticancer effects, particularly for the intestinal tract. Furthermore, its intestinal and topical antimicrobial activities have been its longest recognized effects. Identification of the compounds essential to the activity of garlic, mostly ascribed to its high content of sulfur compounds, has only been partially resolved. So far, the thiosulfinates, of which allicin is 70-80%, are the only compounds with reasonably proven activity at levels representing normal amounts of garlic consumption. They are clearly responsible for the antimicrobial effects. Several evidences also indicate that they are essential to most of the hypolipidemic, antithrombotic, antioxidant, and hypoglycemic effects of garlic, and for some of its anticancer effects. However, because the thiosulfinates are rapidly metabolized and since their active metabolites have not yet been identified, little is known about their mechanism of action. The compounds responsible for the hypotensive effects and much of the anticancer and immune effects of garlic remain unknown. Until they are known, it is best to consume garlic in whole form, fresh or dried.
Historical IntroductionSearch for the Active PrincipleOutline of Method of Isolation of AlliinProperties of AlliinComposition and Constitution of AlliinSynthesis of Alliin and Its Three IsomersAlliinaseQuestions Regarding the Therapeutic Use of Alliin
Supercritical fluid (SF) extracts of homogenized ramp (Allium tricoccum Ait.) were separated and characterized with liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometric identification. The profiles of SF extracts of aqueous homogenates of ramp bulbs from three different seasons and growing regions revealed that the thiosulfinates were major components. In addition, some of the cepaenes (α-sulfinyldisulfides) found in extracts of onion juice, as well as allyl containing cepaenes (2-propenyl 1-(2-propenylsulfinyl)propyl disulfide), are present in the ramp extracts. The amount of allicin in ramp bulb homogenates ranged from approximately 10% to 50% of that found in extracts of aqueous garlic homogenates. The greater amount of the methyl 1-propenyl thiosulfinates in the ramp extracts relative to that found in the garlic extracts correlates with the flavor characteristics of ramp bulbs.
Summary Volatile sulfur compounds produced enzymatically fromAllium species have been identified by combined gas chromatography-mass spectrometry (GC-MS) and the results obtained have been
compared with those from HPLC-UV analysis (with a diode-array detection, DAD). Analysis of the same onion sample by successive
SPME-GC-MS or by solvent extraction then GC-MS enabled us to identify the true onion volatiles including lachrymatory factor
and thiosulfinates. Conversely, for garlic samples HPLC analysis is more suitable because of the substantial degradation of
allicin (the main thiosulfinate in garlic) during GC. An El mass spectrum of allicin obtained by GC-MS is reported for the
first time.
Supercritical fluid (SF) extracts of homogenized garlic (Allium sativum L.), ramp (A. tricoccum Ait.), and onion (A. cepa) were characterized with liquid chromatography (LC) and atmospheric pressure chemical ionization mass spectrometric identification. The major thiosulfinates from garlic and ramp were readily characterized by this technique. Small quantities of ajoene, a potent antithrombotic agent, were also found in SF extracts of garlic homogenates. The profiles of onion juice extracts revealed the usual thiosulfinates, zwiebelanes, and bissulfine reported in prior studies, as well as cepaenes previously identified in extracts of onion juice through extensive isolation steps and spectroscopic methods. The presence of trace quantities of allyl compounds in onion juice and propyl compounds in garlic and ramp homogenates has been verified by LC−mass spectrometry (MS). The presence of these compounds was not readily evident in previous analyses using gas chromatography−MS with cold-on-column injection and reversed-phase or normal phase LC with UV detection. Keywords: Supercritical fluid extraction; liquid chromatography; mass spectrometry; LC−MS; onion, Allium cepa; garlic, Allium sativum L.; ramp, Allium tricoccum Ait.; thiosulfinates
Supercritical fluid (SF) extracts of fresh garlic (Allium sativum) and fresh onion (Allium cepa) were analyzed by liquid chromatography, gas chromatography (GC), and mass spectrometry (MS). Allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester), the major thiosulfinate found in fresh garlic, was readily extracted by using Supercritical CO2 (SC-CO2). Under SF extraction conditions using a solvent trap, the yield of allicin from a water homogenate of fresh garlic was 98.2%; however, when a solid-phase trap (i.e., condensation on glass beads) was used, the yield of allicin was 124.6% relative to yields obtained with methylene chloride extraction. An increase in the quantity of thermal decomposition products with respect to allicin was evident when the garlic was extracted at temperatures greater than 36 degrees C. The identity of allicin in the garlic SF extracts was confirmed by thermospray MS. The SF extraction of yellow onion was ca. 69% as efficient as the extraction with diethyl ether, as determined by GC-MS.
Using the method of standard additions, two different methods of estimating the standard deviation and associated confidence interval for the concentration of an analyte are quoted in commonly used textbooks. It is shown, numerically and algebraically, that a method using the law of propagation of errors invariably gives lower values for the standard deviation than a second technique, which uses extrapolation. On examining the statistical reasoning used in the law of propagation of errors method, it is found that certain covariance terms are assumed to be negligible. Only when combining variables that are truly independent is this assumption valid, which is not the case in standard additions analysis. Consequently the equation used in the extrapolation method is recommended in estimating the standard deviation and confidence interval. Keywords (Audience): Second-Year Undergraduate
This communication is a warning to potential users of allicin, which is adsorbed on silicate carriers, to be used either as an analytical standard or as a source of allicin for biological experiments. Preparations of this type are invalid as calibrators, since they do not liberate their allicin content quantitatively and unchanged.
An analytical method for the determination of allicin (diallyl thiosulfinate) in garlic (Allium sativum L.) samples using reversed-phase HPLC with both UV and electrochemical detection (ED) and on-line post-column photochemical reaction is reported. Standard allicin was synthesised and its behaviour at the chosen analytical conditions was tested. The post-column irradiation at 254 nm on the one hand decreased the response of allicin to UV detector, and on the other hand, allowed the determination of this compound, which is otherwise electrochemically inactive, using the electrochemical detector. Detection limits of 0.1 and of 0.01 mg/l using UV and ED detectors, respectively, and linearity of response in the range 1–8 mg/l were obtained. Samples of garlic extracts, obtained following two different extraction procedures, were analysed and the results obtained using both UV and electrochemical detectors were compared.
Supercritical fluid chromatography—mass spectrometry has been used successfully to identify allicin (2-propene-1-sulfinothioic
acid S-2-propenyl ester), the predominant thiosulfinate in freshly cut garlic (Allium sativum). A low oven temperature (50°C) and low restrictor tip temperature (115°) were needed in order to obtain a chemical ionization
(CI) mass spectrum of allicin with the protonated molecular ion, m/z 163, as the major ion. The effects of tip temperature on the CI mass spectrum of allicin are presented.
Garlic has been claimed to be effective against diseases, in the pathophysiology of which oxygen free radicals (OFRs) have been implicated. Effectiveness of garlic could be due to its ability to scavenge OFRs. However, its antioxidant activity is not known. We investigated the ability of allicin (active ingredient of garlic) contained in the commercial preparation Garlicin to scavenge hydroxyl radicals (.OH) using high pressure liquid chromatographic (HPLC) method. .OH was generated by photolysis of H2O2 (1.25-10 mumoles/ml) with ultraviolet light and was trapped with salicylic acid which is hydroxylated to produce .OH adduct products 2,3- and 2,5-dihydroxybenzoic acid (DHBA). H2O2 produced a concentration-dependent .OH as estimated by .OH adduct products 2,3-DHBA and 2,5-DHBA. Allicin equivalent in Garlicin (1.8, 3.6, 7.2, 14.4, 21.6, 28.8 and 36 micrograms) produced concentration-dependent decreases in the formation of 2,3-DHBA and 2,5-DHBA. The inhibition of formation of 2,3-DHBA and 2,5-DHBA with 1.8 micrograms/ml was 32.36% and 43.2% respectively while with 36.0 micrograms/ml the inhibition was approximately 94.0% and 90.0% respectively. The decrease in .OH adduct products was due to scavenging of .OH and not by scavenging of formed .OH adduct products. Allicin prevented the lipid peroxidation of liver homogenate in a concentration-dependent manner. These results suggest that allicin scavenges .OH and Garlicin has antioxidant activity.
Supercritical fluid (SF) extracts of homogenized ramp (Allium tricoccum Ait.) were separated and characterized with liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometric identification. The profiles of SF extracts of aqueous homogenates of ramp bulbs from three different seasons and growing regions revealed that the thiosulfinates were major components. In addition, some of the cepaenes (alpha-sulfinyldisulfides) found in extracts of onion juice, as well as allyl containing cepaenes (2-propenyl l-(2-propenylsulfinyl)propyl disulfide), are present in the ramp extracts. The amount of allicin in ramp bulb homogenates ranged from approximately 10% to 50% of that found in extracts of aqueous garlic homogenates. The greater amount of the methyl 1-propenyl thiosulfinates in the ramp extracts relative to that found in the garlic extracts correlates with the flavor characteristics of ramp bulbs.
The objective of this review is to examine briefly the medical uses of garlic throughout the ages and the role that it was considered to play in prevention and treatment of disease. Interest in the potential benefits of garlic has origins in antiquity and is one of the earliest documented examples of plants employed for treatment of disease and maintenance of health. Garlic was in use at the beginning of recorded history and was found in Egyptian pyramids and ancient Greek temples. There are Biblical references to garlic. Ancient medical texts from Egypt, Greece, Rome, China and India each prescribed medical applications for garlic. In many cultures, garlic was administered to provide strength and increase work capacity for laborers. Hippocrates, the revered physician, prescribed garlic for a variety of conditions. Garlic was given to the original Olympic athletes in Greece, as perhaps one of the earliest "performance enhancing" agents. It is of interest that cultures that developed without contact with one another came to similar conclusions about the efficacy of garlic. Modern science is tending to confirm many of the beliefs of ancient cultures regarding garlic, defining mechanisms of action and exploring garlic's potential for disease prevention and treatment.
Most garlic supplements are standardized on allicin potential and are enteric-coated to prevent gastric acid inactivation of the allicin-producing enzyme, alliinase. To determine whether these products release the claimed amount of allicin under simulated gastrointestinal conditions, USP dissolution method 724A for drug release was applied to all 24 known brands of enteric-coated tablets. It was found that nearly all brands employed effective coatings and that they met their claims for allicin potential when crushed and suspended in water. However, all brands except one gave low dissolution allicin release, with 83% of the brands releasing less than 15% of their potential. The low allicin release was found to be due to both impaired alliinase activity, mostly caused by tablet excipients, and to slow tablet disintegration, which also impairs alliinase activity. Only when tablets had high alliinase activity and disintegrated rapidly did they show high allicin release. The ability of USP 724A to estimate allicin release in vivo was validated by monitoring breath levels of the allicin metabolite, allyl methyl sulfide. In conclusion, garlic powder supplements should no longer be standardized on allicin potential, but rather on dissolution allicin release.
The diverse health benefit effects of garlic include its anticancer activity. However, very little is known about such activity of isolated garlic compounds, among which allicin (the major ingredient of crushed garlic) has been the least studied. The aim of this work was to determine whether pure allicin exhibits the antiproliferative effect reported for garlic in in vitro models. Allicin, but not its precursor alliin, inhibited proliferation of human mammary (MCF-7), endometrial (Ishikawa), and colon (HT-29) cancer cells (50% inhibitory concentration = 10-25 microM). Two of three tested primary lines of human fibroblasts displayed a similar response to allicin (50% inhibitory concentration = 16-40 microM), whereas the third line was almost unaffected by this compound. The pure allicin and water extract of garlic powder with equivalent allicin concentrations displayed a similar potency, suggesting that allicin is responsible for the antiproliferative effect of the extract. The growth inhibition was accompanied by accumulation of cells in the G0/G1 and G2/M phases of the cell cycle (MCF-7 cells) and not by a significant increase in cell death. Allicin caused a transient drop in the intracellular glutathione (GSH) level, the magnitude and kinetics of which significantly varied depending on cell type. The extent of the decrease in GSH levels correlated well (r = 0.75) with the growth inhibitory activity of allicin. On the basis of these findings, we suggest that allicin plays a major role in the antiproliferative effect of water-soluble garlic preparations and that this effect may be attributed to the ability of allicin to transiently deplete the intracellular GSH level.
The procedure for allicin synthesis could be improved. The time for HPLC analysis of allicin was shortened by the application of different isocratic elution systems. Calibration was performed by use of an allicin/silica gel adsorbate as external standard and its allicin content could be confirmed by different methods. L-(+)-Alliin was synthesized and applied as external standard for the quantitative determination of alliin by HPLC. Diastereoisomers had been separated by repeated recrystallization. Fresh ALLIUM SATIVUM bulbs from different origins were analyzed with respect to allicin content after complete enzymatic conversion of alliin; allicin contents found were in the range of 0.4%. The corresponding alliin contents were in the range of 0.9%. For a comparative evaluation of the alliin- and the allicin-HPLC determination methods, commercially available garlic preparations were analyzed, demonstrating that both methods are appropriate. However, the application of the HPLC system for allicin determination, in addition to providing information on the alliin-dependent allicin-generating capacity, enables the simultaneous quantification of allicin transformation products, such as ajoenes, dithiins, and alkyl sulfides. It was found that, for quantitative GLC analysis of allicin, allicin has to be used as an external standard.
Constituents of crushed garlic bulbs ( ALLIUM SATIVUM L.), such as allicin, ( E/Z)-ajoene, and the vinyldithiins, were synthesized and purified by an LC method. Purity was proved by TLC, HPLC, and GC systems. Identity was confirmed by comparison with spectral data from the literature. In order to establish external standards, silica gel adsorbates of the respective substances were prepared. For quantitative determination of allicin and its transformation products, an isocratic HPLC method was developed. Calibration was performed by the use of these external standards, and by comparison to an internal standard. The influence of different media on allicin transformation, including the ( E/Z)-ratio of the ajoenes, has been elaborated.
The effects of pH, neutralization after acidification, time, and temperature on the yield of dialkyl thiosulfinates released from garlic powder and garlic cloves were determined. All dipropenyl thiosulfinates (allicin, 1-propenyl allyl, and allyl 1-propenyl) were formed at an optimum pH of 4.5-5.0. The methyl propenyl thiosulfinates (allyl methyl + methyl allyl and 1-propenyl methyl + methyl 1-propenyl) and dimethyl thiosulfinate were optimally formed at pH 6.5-7.0 and pH 5.5, respectively. Below pH 3.6 no thiosulfinates were formed. Neutralization of the pH failed to restore thiosulfinate generation from garlic previously incubated at pH 3 or below. Thus, alliinase is completely and irreversibly inhibited by the acidic conditions found in the stomach. The dipropenyl thiosulfinates were completely formed in 0.3 min at 37 degrees C, while the methyl thiosulfinates were not completely formed until 3.5 min. Allyl 1-propenyl thiosulfinate was the most rapidly formed, and the most unstable, thiosulfinate. The stability of the dipropenyl thiosulfinates was improved at pH 4.5 or lower. Drying garlic at 60 degrees C had no effect on alliin or the rate of formation of the dipropenyl thiosulfinates, but decreased trans-1-propenylcysteine sulfoxide (isoalliin) and the rate of formation of the methyl thiosulfinates. The results demonstrate that there are two alliinase activities in garlic, that a stomach acid-resistant coating on garlic powder tablets is necessary for thiosulfinate release, and that carefully prepared garlic powder can release similar amounts of total thiosulfinates to whole garlic cloves.
Reversed-phase high Performance liquid chromatography (C18-HPLC) was used to separate and quantitate all the detectable alkyl and alkenyl thiosulfinates, including configurational isomers, of garlic homogenates. Pure thiosulfinates were synthesized or isolated and identified by (1)H-NMR, and their extinction coefficients determined. Some configurational isomers required Separation by silica-HPLC. Five previously unreported thiosulfinates have been found, four of which contain the TRANS-1-propenyl group and increase several-fold to over half the content of allicin upon storage of garlic bulbs at 4 degrees C with a concomitant decrease in a gamma-glutamyl peptide. The variation in thiosulfinate yield between different countries, stores, bulbs, cloves, and storage times was investigated. A method for standardizing the quantitation of allicin yield from garlic is proposed and compared to other methods of allicin analysis.
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- L D Lawson
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Chemical investigations on alliin, the specific principle of garlic
- A Stoll
- E Seebeck
Stoll, A.; Seebeck, E. Chemical investigations on alliin, the
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