Showing papers on "Allicin published in 2000"

Activities of Garlic Oil, Garlic Powder, and Their Diallyl Constituents against Helicobacter pylori

Abstract: Chronic Helicobacter pylori disease is reduced with Allium vegetable intake. This study was designed to assess the in vivo anti- H. pylori potential of a variety of garlic substances. The garlic materials all showed substantial but widely differing anti- H. pylori effects against all strains and isolates tested. The MICs (range, 8 to 32 μg/ml) and minimum bactericidal concentrations (MBCs) (range, 16 to 32 μg/ml) of undiluted garlic oil (GO) were smaller than those of garlic powder (GP) (MIC range, 250 to 500 μg/ml; MBC range, 250 to 500 μg/ml) but greater than the MIC of allicin (4.0 μg/ml) (Table 2) present in GP. Allicin (MIC, 6 μg/ml; MBC, 6 μg/ml) was more potent than diallyl disulfide (MIC range, 100 to 200 μg/ml; MBC range, 100 to 200 μg/ml), its corresponding sulfide, but of a strength similar to that of diallyl tetrasulfide (MIC range, 3 to 6 μg/ml; MBC range, 3 to 6 μg/ml). Antimicrobial activity of the diallyl sulfides increased with the number of sulfur atoms. Time course viability studies and microscopy showed dose-dependent anti- H. pylori effects with undiluted GO, GP, allicin, and diallyl trisulfide after a lag phase of ca. 1 to 2 h. Substantial in vitro anti- H. pylori effects of pure GO and GP and their diallyl sulfur components exist, suggesting their potential for in vivo clinical use against H. pylori infections.

Effect of purified allicin, the major ingredient of freshly crushed garlic, on cancer cell proliferation

Abstract: 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.

Effect of allicin from garlic powder on serum lipids and blood pressure in rats fed with a high cholesterol diet

Abstract: The use of fresh aqueous garlic extract is known to be effective in reducing thromboxane formation by platelets in both in vivo and in vitro animal models of thrombosis. In the present study, we studied the effect of Lichtwer garlic powder (containing 1.3% alliin equivalent to 0.6% allicin) on the serum cholesterol, triglyceride, glucose, protein, and systolic blood pressure in rats fed with a high cholesterol diet. Experimental rats were fed a 2% high cholesterol diet with and without garlic powder for 6 weeks. Control rats were fed a normal diet. The aqueous garlic powder extract was given orally to rats on a daily basis. It was observed that cholesterol-fed animals had a significant increase in serum cholesterol compared to the control group of rats fed on a normal diet. However, when the rats were fed with a high cholesterol diet mixed with garlic powder, there was a significant reduction in their serum cholesterol levels compared with the group which were on a diet containing high cholesterol without garlic powder. Serum triglyceride levels were also significantly lowered by garlic powder when compared to control and high cholesterol diet group rats. The blood pressure of the high cholesterol diet animals was significantly higher compared to the animals receiving the control diet. The blood pressure of the animals receiving garlic powder and high cholesterol diet was significantly lower as compared to the high cholesterol and control diet group. No significant changes were observed in the serum glucose and protein in all of the rats. These results show that garlic is beneficial in reducing blood cholesterol, triglycerides levels and systolic blood pressure in hypercholesterolemic rats. Our experimental results show that garlic may beneficially affect two risk factors for atherosclerosis--hyperlipidemia and hypertension.

Differential inhibition of human platelet aggregation by selected Allium thiosulfinates.

Abstract: Thiosulfinates (TSs) have been implicated as a principle source of the antiplatelet property of raw onion and garlic juice. The in vitro responses of human platelets to dosages of four TSs were measured using whole blood aggregometry and compared by regression analysis. Of the compounds evaluated, methyl methane-TS (MMTS), propyl propane-TS (PPTS), and 2-propenyl 2-propene-TS (allicin) are present in freshly cut Allium vegetables, whereas ethyl ethane-TS (EETS) has not been detected. All TSs were synthesized using a model reaction system. PPTS and allicin had the strongest antiplatelet activity at 0.4 mM, inhibiting aggregation by 90 and 89%, respectively. At the same concentration, EETS and MMTS were significantly weaker, inhibiting 74 and 26%, respectively. Combinations of TSs were not additive in their inhibition of aggregation, indicating that the antiplatelet potential of Allium extracts cannot be easily predicted by quantifying organosulfur components. EETS, PPTS, and allicin were significantly more potent platelet inhibitors than aspirin at nearly equivalent concentrations.

The mode of action of allicin: Its ready permeability through phospholipid membranes may contribute to its biological activity. Biochimica et Biophysica Acta, 1463, 20-30

Abstract: Allicin (diallyl thiosulfinate) is the main biologically active component of the freshly crushed garlic extracts. In the present work the ability of allicin to cross through membranes (artificial and biological) was studied. Partition coefficients of allicin in water/octanol, water/hexadecane and water/phospholipids mixtures were determined. Using phospholipid vesicles loaded with hydrophilic thiols (reduced glutathione or 2-nitro-5-thiobenzoate), we observed that allicin freely permeates through phospholipid bilayers and interacts with the SH groups. The reaction rate of allicin with SH containing molecules after crossing the membrane was the same as in solution. Fast diffusion and permeation of allicin across human red blood cell membranes was also demonstrated. Allicin does not induce leakage, fusion or aggregation of membrane. The high permeability of allicin through membranes may greatly enhance the intracellular interaction with thiols.

Analysis of responses of garlic derivatives in the pulmonary vascular bed of the rat.

Abstract: Allicin, an extract from garlic, has been shown to be a systemic and pulmonary arterial vasodilator that acts by an unknown mechanism. In the present experiments, pulmonary vascular responses to al...

Effects of wild versus cultivated garlic on blood pressure and other parameters in hypertensive rats.

Abstract: Two separate studies were performed on hypertensive rats to assess the effects of wild, uncultivated garlic on elevated systolic blood pressure (SBP) and other cardiovascular parameters. Also, effects of wild garlic and cultivated garlic preparations were compared and the mechanisms behind pressure-lowering abilities of different garlic preparations were examined. The initial study determined that wild garlic lowers blood pressure. In the second study, cardiovascular effects of three different concentrations of wild garlic and two different cultivated garlics, i.e., a preparation low in allicin and one high in allicin, were compared. All three garlic preparations decreased SBP significantly. Wild garlic produced the greatest pressure-lowering effects, and the least pressure-lowering effects were seen with low-allicin garlic. Compared with control rats, circulating angiotensin II levels were significantly lower in all garlic-eating rats. Losartan decreased blood pressure significantly less and Nw-nitro-L arginine-methyl ester hydrochloride (LNAME) increased blood pressure significantly more in garlic-eating rats than in control rats, suggesting that the renin-angiotensin system (RAS) was less active and the nitric oxide system more active in garlic-consuming hypertensive rats. Accordingly, different garlic preparations, especially wild garlic, favorably influenced high SBP in hypertensive rats. These results suggest that both the RAS and the nitric oxide system are involved in the antihypertensive effects of garlic in hypertensive rats.

Toxicity to the snail Limnaea acuminata of plant-derived molluscicides in combination with synergists

Abstract: The effects of combinations of plant-derived molluscicides with piperonyl butoxide (PB) or ENT 8184 (MGK-264) were studied on different enzyme activities and biogenic amine levels in the nervous tissue of Limnaea acuminata. 24-h in vivo exposure of the nervous tissue of L acuminata to 40% and 80% of the 24-h LC 50 of the plant-derived molluscicides Azadirachta indica oil, Allium sativum powder and oleoresin of Zingiber officinale rhizome and their active molluscicidal components azadirachtin, allicin and [6]-gingerol, alone or in combination (1+5) with PB or ENT 8184, caused a significant reduction in the activity of acetylcholinesterase, lactic dehydrogenase, acid and alkaline phosphatases and sodium-potassium ATPase. There was a significant increase in the activity of succinic dehydrogenase. In vivo exposure for 24h to sub-lethal concentrations of azadirachtin, allicin and [6]-gingerol, singly and with PB or ENT 8184, significantly altered the dopamine and 5-hydroxytryptamine levels in the nervous tissue of L acuminata. It is concluded that these active moieties singly or with PB or ENT 8184 adversely affect all known neurotransmission mechanisms in the snail, either separately or through a complex interaction between the different neurotransmitters.

The determination of metabolites of garlic preparations in breath and human plasma

Abstract: Gas Chromatography–Mass Spectrometry (GC- MS) was the major technique used to determine various metabolites after consumption of dehydrated granular garlic and an enteric-coated garlic preparation, in breath, plasma, and simulated gastric fluids A special short-path thermal desorption device [1] was used as an introduction technique for the gas chromatograph for the determination of volatiles These garlic preparations release allicin, which decomposes in stomach acid or with time in the intestine to release allyl sulfides, disulfides and other volatiles, some of which are postulated to be metabolized by glutathione and/or S-adenosylmethionine to form allyl methyl sulfide, the main sulfur containing volatile metabolite S-Allylcysteine, a non-volatile bioactive component of aged garlic preparations, was determined in human plasma and urine by HPLC-MS using the negative ion atmospheric pressure chemical ionization mode (APcI)- MS The technique of selected ion monitoring was used for quantitation A synthetic internal standard of deuterated S-allylcysteine was added to the plasma or urine to ensure recovery and to obtain reliable quantitative data

Thermochemical transformation of sulfur compounds in Japanese domestic Allium, Allium victorialis L.

Abstract: Sulfur compounds contributed to the health promotion in Allium species are produced via enzymic and thermal reactions. Potent antithrombotic agents which have been identified as allyl trisulfides, dithiins, and ajoene in garlic (A. sativum) and caucas (A. victorialis) are thermochemically transformed from allicin (allyl 2-propenethiosulfinate). The leaves and stems of Japanese domestic Allium plant, A. victorialis L. which is widely distributed in the northern part of Japan, under the name "Gyoja-ninniku" is a nutritious vegetable. The significant flavor compounds of caucas are methyl allyl disulfide (Chinese chive odor), diallyl disulfide (garlic-like odor), and dimethyl disulfide and methyl allyl trisulfide (pickles-like odor) among more than 85 peaks on the gas chromatogram. 2-Vinyl-4H-1,3-dithiin and 3,4-dihydro-3-vinyl-1,2-dithiin as platelet aggregation inhibitors were found eliminated in dichloromethane extract of caucas. The significant health promoting factors, allyl trisulfides and dithiins were relatively increased when caucas was cooked on a frying pan.

Repellent effect of garlic against stored product pests.

Abstract: Intact garlic clove, grated garlic and its volatile extract applied on brown rice showed a repellent effect but no insecticidal activity against two stored product pests, i.e. the maize weevil and the red flour beetle. Neither repellency nor insecticidal activity was observed with garlic or its extract against two agricultural pests, diamondback moth larvae and green peach aphids. In comparative tests, hot pepper and wasabi mustard demonstrated only weak repellency, if any, although volatile components of wasabi mustard showed insecticidal activity against these insects. Volatile components of garlic were trapped and subjected to GC-MS analysis. Four major peaks resolved were sulfide compounds produced by the rapid degradation of allicin and a cyclic compound produced by dehydration. It remains to be determined whether allicin itself, the degradation products, or the mixture of these are responsible for the repellent effect.

A comparative study on hypocholesterolaemic effect of allicin, whole germinated seeds of bengal gram and guggulipid of gum gugglu.

Abstract: The daily use of allicin and whole germinated bengal gram seeds for 8 weeks led to a significant decrease in serum cholesterol levels in normal volunteers with no side effects. The standard reference, guggulipid therapy, significantly (p < 0.001) reduced the mean serum cholesterol level to 142.88 +/- 24.14 mg/100 mL from an initial status of 211.91 +/- 6.23 mg/100mL (32.36% +/- 12.48% fall). Allicin treatment significantly reduced the mean serum cholesterol level to 129.99 +/- 2.79 mg/100 mL from a pre-treatment value of 148.10 +/- 8. 81 mg/100mL, a fall of 13.36% +/- 4.64%. The serum cholesterol value was reduced to 135.62+/- 22.85 mg/100 mL from a pre-treatment value of 157.29 +/- 4.94 mg/100mL (17.15% +/- 9.94% fall) due to daily use of whole germinated bengal gram seeds. Hence the hypocholesterolaemic effects of allicin and whole germinated bengal gram seeds are comparable to the established standard reference, guggulipid. These two materials are herbal in origin and it is supposed to have a lesser risk-benefit ratio compared with other available synthetic drugs. The inclusion of these herbal products in the normal diet may be an alternative effective measure for hypercholesterolaemia.

Ligustrazine, allicin and shear-induced platelet aggregation.

Abstract: the efficacy of ligustrazini and allicin on SIPA of New Zealand rabbits. The results show that the 50% inhibition concentration (IC50) of ligustrazine on SIPA was 0.52 mM. The IC50 of allicin was 1.27 mM. We further studied the mechanism by using monoclonal antibody of GP Ib and Fluo-3/AM with laser confocal microscope. We found that both compounds inhibited calcium channel in the platelet membrane without involvement in activating GP Ib. Ligustrazini of 0.22‐0.88 mmol/l and allicin of 0.42‐1.68 mmol/l significantly inhibited SIPA ( P< 0.001) and calcium inflow ( P< 0.01). Moreover, we conducted a pilot trial of 10 cardiovascular patients to determine ligustrazini’s effect on human SIPA, SIPA induced by stenosis level of stress was markedly inhibited by single dripping of ligustrazini of 80 mg, indicated by a decrease in SIPA of 12.0 6.95% ( P< 0.001). Susceptibility to atherosclerosis and stenosis of arteries in the elderly leads to the abnormally high wall shear stress of blood flow. SIPA is likely to happen in the cerebrovascular domain due to its high flow volume and velocity. Our research is at the junction of bio-mechanism, geriatrics, antithrombosis,

Use of allicin for control of weight in mammals

Abstract: Allicin is used for control of weight in mammals, in particular for reduction of weight and/or prevention of weight gain, more particularly for prevention of weight gain in an individual who has previously undergone a diet for reducing weight.

Use of garlic extract as both preventive and therapeutic agents for human prostate and bladder cancers

Abstract: This invention is concerned with the clinical investigation of the therapeutic effects of garlic extracts containing allicin, diallyl disulfide, and diallyl trisulfide. The intake of garlic or therapeutically active substances such as allicin from garlic, induces immunostimulation and these active substances possess strong antitumor effects including the apoptosis of tumors, including the programmed cell death of human prostatic and bladder tumor cells. This invention claims that garlic and/or garlic extracts possess very effective therapeutic substances useful not only to treat human prostate and bladder cancers to extend life span of patients, but also to suppress or prevent bladder and prostate gland cancers.

Skin whitening soap and skin care product containing alliin-vitamin b1 component from garlic

Abstract: PURPOSE: A skin care product is provided to promote the skin whitening effect by adding the physically and chemically changed allicin contained in the garlic to a skin care product or a skin whitening soap. CONSTITUTION: A skin cosmetic is made up of the steps: obtaining the garlic juice by thermal processing of the raw garlic at 60-80°C after peeling and washing, adding the citron juice or the herb and grinding; and maturing by putting the garlic juice into a container and maturing at 25-30°C for 20-30 days, adding alcohol to the garlic juice and maturing at 25-30°C for 10-15 days, or sequentially performing the both maturing processes.