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Yukihiro Kodera - One of the best experts on this subject based on the ideXlab platform.
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antimicrobial properties of hydrophobic compounds in garlic allicin vinyldithiin ajoene and diallyl polysulfides review
Experimental and Therapeutic Medicine, 2019Co-Authors: Masato Nakamoto, Kayo Kunimura, Jun Ichiro Suzuki, Yukihiro KoderaAbstract:Allium plants, such as garlic, onion and leek have long been known to be effective in the therapy of infectious diseases. In particular, garlic has a greater antimicrobial activity than other Allium plants as it contains several hydrophobic antimicrobial compounds, such as allicin, vinyldithiins, ajoenes and diallyl polysulfides. Allicin is a characteristic sulfur-containing compound found in raw garlic produced from alliin and exhibits antimicrobial activity against both Gram-positive and Gram-negative bacteria. In addition, allicin has been reported to inhibit the biofilm formation of bacteria, which is a major cause of bacterial resistance to the antibiotic treatment of infections, by regulating quorum sensing in microorganisms. Other hydrophobic compounds also have similar inhibitory effects on bacteria as allicin. These biological properties of garlic-derived hydrophobic compounds can be used to enhance the effects of existing drugs and may thus be used in the treatment of infections, such as by preventing drug resistance through the inhibition of biofilm formation. In this review, we summarize the effects of hydrophobic compounds of garlic on bacteria.
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Pharmacokinetic study of Allixin, a phytoalexin produced by garlic.
Chemical & pharmaceutical bulletin, 2002Co-Authors: Yukihiro Kodera, Makoto Ichikawa, Jiro Yoshida, Naoki Kashimoto, Naoto Uda, Isao Sumioka, Nagatoshi Ide, Kazuhisa OnoAbstract:The pharmacokinetic behavior of Allixin (3-hydroxy-5-methoxy-6-methyl-2-penthyl-4H-pyran-4-one) was investigated in an experimental animal, mice. Allixin was administered using an inclusion compound because the solubility of Allixin in aqueous solution is very low. The Allixin content in serum and in the organs of administered animals was analyzed by liquid chromatography (LC)-MS. Most of the administered Allixin disappeared within 2 h, and the bioavailability of Allixin was estimated to be 31% by obtained area under the blood concentration-time curve (AUC). The metabolites of Allixin were studied using the metabolic enzyme fraction of liver and liver homogenate. Several new peaks corresponding to Allixin metabolites were observed in the HPLC chromatoprofile. The chemical structure of the metabolites was investigated using LC-MS and NMR. Three of them were identified as Allixin metabolites having a hydroxylated pentyl group.
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Allixin accumulation with long-term storage of garlic.
Chemical & pharmaceutical bulletin, 2002Co-Authors: Yukihiro Kodera, Masanori Ayabe, Kozue Ogasawara, Susumu Yoshida, Norihiro Hayashi, Kazuhisa OnoAbstract:Extremely high accumulation of Allixin, a phytoalexin derived from garlic, was observed in necrotic tissue areas after long-term storage. The Allixin produced recrystallized on the surface of the garlic clove. The amount of Allixin produced in raw garlic with necrotic tissue areas was 1400 ng/mg wet garlic, which exceeds the minimum exhibitory concentration of Allixin. After approximately 2 years of storage, amount of Allixin accumulated reached slightly less than 1% of the dry weight of garlic cloves.
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Allixin induction and accumulation by light irradiation.
Chemical & pharmaceutical bulletin, 2001Co-Authors: Yukihiro Kodera, Masanori Ayabe, Kozue Ogasawara, Kazuhisa OnoAbstract:Allixin, a phytoalexin isolated from garlic, was induced by irradiating fresh garlic cloves with sunlight or UV light. Induced Allixin was analyzed by HPLC, and the accumulated amounts of Allixin were 3.1—6.3 μg/g under experimental conditions.
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garlic chemistry stability of s 2 propenyl 2 propene 1 sulfinothioate allicin in blood solvents and simulated physiological fluids
Journal of Agricultural and Food Chemistry, 1995Co-Authors: Fillmore Freeman, Yukihiro KoderaAbstract:S-(2-Propenyl) 2-propene-1-sulfinothioate (allicin), which is one of the constituents of freshly crushed garlic (garlic homogenate), was synthesized, and its stability in blood, ethyl acetate, methanol, simulated gastric fluid (SGF, pH 1.2), simulated intestinal fluid (SIF, pH 7.5), and water (pH 1.2 and 7.5) and under simulated digestive conditions (sequential combination of SGF and SIF) was investigated by HPLC. Although neat allicin decomposes rapidly at 37 °C, it is more stable in protic polar methanol than in aprotic polar ethyl acetate. Approximately 90% of the allicin remained after incubation at 37 °C for 5 h in water at pH 1.2 and 7.5. Only traces of allicin could be detected after it was incubated in blood for 5 min. The allicin content and allicin-producing potential of commercial garlic preparations were also analyzed. The allicin contents in these garlic preparations were less than 1 ppm, and the allicin-producing potential was severely suppressed under simulated digestive conditions (sequential combination of SGF and SIF). The transformation products of allicin [(E)-ajoene, 2-ethenyl-4H-1,3-dithiin, diallyl disulfide] were identified.
Alan J Slusarenko - One of the best experts on this subject based on the ideXlab platform.
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Diallylthiosulfinate (Allicin), a Volatile Antimicrobial from Garlic (Allium sativum), Kills Human Lung Pathogenic Bacteria, Including MDR Strains, as a Vapor
MDPI AG, 2017Co-Authors: Jana Reiter, Martin C H Gruhlke, Natalja Levina, Mark Van Der Linden, Christian Martin, Alan J SlusarenkoAbstract:Garlic (Allium sativum) has potent antimicrobial activity due to allicin (diallylthiosulfinate) synthesized by enzyme catalysis in damaged garlic tissues. Allicin gives crushed garlic its characteristic odor and its volatility makes it potentially useful for combating lung infections. Allicin was synthesized (>98% pure) by oxidation of diallyl disulfide by H2O2 using formic acid as a catalyst and the growth inhibitory effect of allicin vapor and allicin in solution to clinical isolates of lung pathogenic bacteria from the genera Pseudomonas, Streptococcus, and Staphylococcus, including multi-drug resistant (MDR) strains, was demonstrated. Minimal inhibitory (MIC) and minimal bactericidal concentrations (MBC) were determined and compared to clinical antibiotics using standard European Committee on Antimicrobial Susceptibility Testing (EUCAST) procedures. The cytotoxicity of allicin to human lung and colon epithelial and murine fibroblast cells was tested in vitro and shown to be ameliorated by glutathione (GSH). Similarly, the sensitivity of rat precision-cut lung slices (PCLS) to allicin was decreased by raising the [GSH] to the approximate blood plasma level of 1 mM. Because allicin inhibited bacterial growth as a vapor, it could be used to combat bacterial lung infections via direct inhalation. Since there are no volatile antibiotics available to treat pulmonary infections, allicin, particularly at sublethal doses in combination with oral antibiotics, could make a valuable addition to currently available treatments
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The Effects of Allicin, a Reactive Sulfur Species from Garlic, on a Selection of Mammalian Cell Lines
MDPI AG, 2016Co-Authors: Martin C H Gruhlke, Carole Nicco, Frederic Batteux, Alan J SlusarenkoAbstract:Garlic (Allium sativum L.) has been used as a spice and medicinal plant since ancient times. Garlic produces the thiol-reactive defence substance, allicin, upon wounding. The effects of allicin on human lung epithelium carcinoma (A549), mouse fibroblast (3T3), human umbilical vein endothelial cell (HUVEC), human colon carcinoma (HT29) and human breast cancer (MCF7) cell lines were tested. To estimate toxic effects of allicin, we used a standard MTT-test (methylthiazoltetrazolium) for cell viability and 3H-thymidine incorporation for cell proliferation. The glutathione pool was measured using monobromobimane and the formation of reactive species was identified using 2′,7′-dichlorofluoresceine-diacetate. The YO-PRO-1 iodide staining procedure was used to estimate apoptosis. Allicin reduced cell viability and cell proliferation in a concentration dependent manner. In the bimane test, it was observed that cells treated with allicin showed reduced fluorescence, suggesting glutathione oxidation. The cell lines tested differed in sensitivity to allicin in regard to viability, cell proliferation and glutathione oxidation. The 3T3 and MCF-7 cells showed a higher proportion of apoptosis compared to the other cell types. These data show that mammalian cell lines differ in their sensitivity and responses to allicin
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the defense substance allicin from garlic permeabilizes membranes of beta vulgaris rhoeo discolor chara corallina and artificial lipid bilayers
Biochimica et Biophysica Acta, 2015Co-Authors: Martin C H Gruhlke, Ulrike Noll, Birgit Hemmis, Richard Wagner, Hinrich Luhring, Alan J SlusarenkoAbstract:Abstract Background Allicin (diallylthiosulfinate) is the major volatile- and antimicrobial substance produced by garlic cells upon wounding. We tested the hypothesis that allicin affects membrane function and investigated 1) betanine pigment leakage from beetroot ( Beta vulgaris ) tissue, 2) the semipermeability of the vacuolar membrane of Rhoeo discolor cells, 3) the electrophysiology of plasmalemma and tonoplast of Chara corallina and 4) electrical conductivity of artificial lipid bilayers. Methods Garlic juice and chemically synthesized allicin were used and betanine loss into the medium was monitored spectrophotometrically. Rhoeo cells were studied microscopically and Chara- and artificial membranes were patch clamped. Results Beet cell membranes were approximately 200-fold more sensitive to allicin on a mol-for-mol basis than to dimethyl sulfoxide (DMSO) and approximately 400-fold more sensitive to allicin than to ethanol. Allicin-treated Rhoeo discolor cells lost the ability to plasmolyse in an osmoticum, confirming that their membranes had lost semipermeability after allicin treatment. Furthermore, allicin and garlic juice diluted in artificial pond water caused an immediate strong depolarization, and a decrease in membrane resistance at the plasmalemma of Chara , and caused pore formation in the tonoplast and artificial lipid bilayers. Conclusions Allicin increases the permeability of membranes. General significance Since garlic is a common foodstuff the physiological effects of its constituents are important. Allicin's ability to permeabilize cell membranes may contribute to its antimicrobial activity independently of its activity as a thiol reagent.
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Allicin: Chemistry and Biological Properties
MDPI AG, 2014Co-Authors: Jan Borlinghaus, Martin C H Gruhlke, Frank Albrecht, Ifeanyi D. Nwachukwu, Alan J SlusarenkoAbstract:Allicin (diallylthiosulfinate) is a defence molecule from garlic (Allium sativum L.) with a broad range of biological activities. Allicin is produced upon tissue damage from the non-proteinogenic amino acid alliin (S-allylcysteine sulfoxide) in a reaction that is catalyzed by the enzyme alliinase. Current understanding of the allicin biosynthetic pathway will be presented in this review. Being a thiosulfinate, allicin is a reactive sulfur species (RSS) and undergoes a redox-reaction with thiol groups in glutathione and proteins that is thought to be essential for its biological activity. Allicin is physiologically active in microbial, plant and mammalian cells. In a dose-dependent manner allicin can inhibit the proliferation of both bacteria and fungi or kill cells outright, including antibiotic-resistant strains like methicillin-resistant Staphylococcus aureus (MRSA). Furthermore, in mammalian cell lines, including cancer cells, allicin induces cell-death and inhibits cell proliferation. In plants allicin inhibits seed germination and attenuates root-development. The majority of allicin’s effects are believed to be mediated via redox-dependent mechanisms. In sub-lethal concentrations, allicin has a variety of health-promoting properties, for example cholesterol- and blood pressure-lowering effects that are advantageous for the cardio-vascular system. Clearly, allicin has wide-ranging and interesting applications in medicine and (green) agriculture, hence the detailed discussion of its enormous potential in this review. Taken together, allicin is a fascinating biologically active compound whose properties are a direct consequence of the molecule’s chemistry
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allicin disrupts the cell s electrochemical potential and induces apoptosis in yeast
Free Radical Biology and Medicine, 2010Co-Authors: Martin C H Gruhlke, Daniela Portz, Michael Stitz, Nikolaus Ludwig Schlaich, Awais Anwar, Claus Jacob, Alan J SlusarenkoAbstract:Abstract The volatile substance allicin gives crushed garlic (Allium sativum) its characteristic odor and is a pro-oxidant that undergoes thiol–disulfide exchange reactions with –SH groups in proteins and glutathione. The antimicrobial activity of allicin is suspected to be due to the oxidative inactivation of essential thiol-containing enzymes. We investigated the hypothesis that at threshold inhibitory levels allicin can shunt yeast cells into apoptosis by altering their overall redox status. Yeast cells were treated either with chemically synthesized, pure allicin or with allicin in garlic juice. Allicin-dependent cell oxidation was demonstrated with a redox-sensitive GFP construct and the shift in cellular electrochemical potential (Ehc) from less than − 215 to − 181 mV was calculated using the Nernst equation after the glutathione/glutathione disulfide couple (2GSH/GSSG) in the cell was quantified. Caspase activation occurred after allicin treatment, and yeast expressing a human antiapoptotic Bcl-XL construct was rendered more resistant to allicin. Also, a yeast apoptosis-inducing factor deletion mutant was more resistant to allicin than wild-type cells. We conclude that allicin in garlic juice can activate apoptosis in yeast cells through its oxidizing properties and that this presents an alternative cell-killing mechanism to the previously proposed specific oxidative inactivation of essential enzymes.
H.d. Rabinowitch - One of the best experts on this subject based on the ideXlab platform.
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Diversity in fertility potential and organo-sulphur compounds among garlics from Central Asia
Biodiversity & Conservation, 2005Co-Authors: R. Kamenetsky, I. London Shafir, F. Khassanov, A.w. Van Heusden, M. Vrielink-van Ginkel, K. Burger-meijer, J. Auger, I. Arnault, H.d. RabinowitchAbstract:Extending the collection of garlic ( Allium sativum L.) accessions is an important means that is available for broadening the genetic variability of this cultivated plant, with regard to yield, quality, and tolerance to biotic and abiotic traits; it is also an important means for restoring fertility and flowering. In the framework of the EU project ‘Garlic and Health’, 120 garlic accessions were collected in Central Asia – the main centre of garlic diversity. Plants were documented and thereafter maintained in field collections in both Israel and The Netherlands. The collection was evaluated for biological and economic traits. Garlic clones vary in most vegetative characteristics (leaf number, bulb size and structure), as well as in floral scape elongation and inflorescence development. A clear distinction was made between incomplete bolting and bolting populations; most of the accessions in the latter populations produced flowers with fertile pollen and receptive stigma. Wide variations were recorded with regard to differentiation of topsets, their size, number and rapidity of development. Furthermore, significant variation in organo-sulphur compounds (alliin, isoalliin, allicin and related dipeptides) was found within garlic collections and between plants grown under differing environmental conditions. Genetic fingerprinting by means of AFLP markers revealed three distinct groups within this collection, differing also in flowering ability and organo-S content.
Kuniyoshi Shimizu - One of the best experts on this subject based on the ideXlab platform.
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An LC-MS/MS-SRM Method for Simultaneous Quantification of Four Representative Organosulfur Compounds in Garlic Products
Food Analytical Methods, 2016Co-Authors: Kenichi Kakino, Chika Nogami, Koichiro Ohnuki, Kuniyoshi ShimizuAbstract:The quantitative analysis of organosulfur compounds is important for the quality control of various garlic products along with studying their molecular functionality and nutraceutical properties. In this study, a liquid chromatography-tandem mass spectrometry-selected reaction monitoring (LC-MS/MS-SRM) method with electrospray ionization detection was developed and validated for the rapid, simultaneous quantification of four representative organosulfur compounds in garlic: alliin, S-allyl-L-cysteine, γ-glutamyl-S-allyl-L-cysteine, and allicin. Stable SRM transitions were achieved for these compounds under optimized conditions, and the linear range extended from 1 to 2000 ng/mL. The limits of detection and quantification ranged from 0.003 to 0.058 ng/mL and from 0.01 to 0.19 ng/mL, respectively. Excellent recovery and reproducibility at different spiking levels were achieved. The method was successfully applied to the simultaneous quantification of organosulfur compounds in fresh garlic samples. This highly selective and sensitive LC-MS/MS-SRM method is expected to be a useful tool for studying molecular functionality and the quality control of garlic products.
Nobuyoshi Nishiyama - One of the best experts on this subject based on the ideXlab platform.
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Allixin, a phytoalexin produced by garlic, and its analogues as novel exogenous substances with neurotrophic activity
Life sciences, 1997Co-Authors: Toru Moriguchi, Hiromichi Matsuura, Yoichi Itakura, Hiroshi Katsuki, Hiroshi Saito, Nobuyoshi NishiyamaAbstract:Effects of Allixin, a phytoalexin of garlic, and its analogues were studied on the survival and morphology of primary cultured neurons from fetal rat brain. Addition of Allixin (1–100 ngml) to medium significantly promoted the survival of neurons derived from various regions of brain and increased the number of branching points per axon in hippocampal neurons. Allixin, however, was cytotoxic at higher concentrations (> 1 μgml). Among the analogues of Allixin, 2,6-dimethyl-3-hydroxy-4H-pyran-4-one (DHP) possessed potent neurotrophic activity at concentrations over 10 ngml without any obvious cytotoxicity up to 10 μgml. DHP also retained the activity to promote axonal branching. These results indicate that DHP is a novel exogenous low molecular weight neurotrophic substance without apparent cytotoxicity. This compound may be a useful prototype leading chemical for developing therapeutic and/or prophylactic drugs for neurodegenerative disorders.