garlic
Antioxidant and radical scavenging effects of aged garlic extract and its constituents.

Imai J, Ide N, Nagae S, Moriguchi T, Matsuura H, Itakura Y.

Institute for OTC Research, Wakunaga Pharmaceutical Co. Ltd., Hiroshima, Japan.

The antioxidant properties of three garlic preparations and organosulfur compounds in garlic have been determined. Aged garlic extract inhibited the emission of low level chemiluminescence and the early formation of thiobarbituric acid-reactive substances (TBA-RS) in liver microsomal fraction initiated by t-butyl hydroperoxide. However, the water extracts of raw and heat-treated garlic enhanced the emission of low level chemiluminescence. Among the variety of organosulfur compounds, S-allylcysteine (SAC) and S-allylmercaptocysteine (SAMC), the major organosulfur compounds found in aged garlic extract, showed radical scavenging activity in both chemiluminescence and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, indicating that these compounds may play an important role in the antioxidative activity of aged garlic extract.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7997468&dopt=Abstract garlic



garlic
Staphylococcal growth and enterotoxins (A-D) and thermonuclease synthesis in the presence of dehydrated garlic.

Gonzalez-Fandos E, Garcia-Lopez ML, Sierra ML, Otero A.

Department of Food Hygiene and Food Technology, Veterinary Faculty, University of Leon, Spain.

The inhibition of Staphylococcus aureus growth and enterotoxin and thermonuclease production by various concentrations of garlic (Allium sativum) was studied in BHI broth. The growth of Staph. aureus was inhibited by dehydrated garlic at levels of 1.5% (w/v) and over. Enterotoxins A, B and C1 were only detectable in broth containing < 1% of garlic while enterotoxin D was produced at a level of 2%. Garlic also inhibited thermonuclease (TNAse) production, complete inhibition being observed at levels > or = 1.5%. TNAse was not always detected when enterotoxin was present.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8002479&dopt=Abstract garlic



garlic
Effectiveness of garlic on the radical activity in radical generating systems.

Torok B, Belagyi J, Rietz B, Jacob R.

Central Research Laboratory, University Medical School, Pecs, Hungary.

The radical scavenging capacity of garlic (allium sativum) has been investigated in vitro in radical generating systems by electron paramagnetic resonance (EPR) and low-level chemiluminescence measurements. Garlic (both the homogenate of 10% in physiological saline solution and its supernatant) was able to reduce the radicals generated by the Fenton reaction and trapped by phenyl-butyl-nitron for EPR measurements. Also radicals present in cigarette smoke could be reduced by garlic as judged from chemiluminescence in the presence of tert.-butyl-hydroperoxide. According to the in vitro measurements garlic contains substances which have significant radical scavenging capacity.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8024631&dopt=Abstract garlic



garlic
Effects of dietary garlic supplementation in a rat model of atherosclerosis.

Heinle H, Betz E.

Institute of Physiology I, University of Tubingen, Fed. Rep. of Germany.

In the present study possible antiatherogenic effects of dietary garlic were investigated in an experimental model which consists in the deendothelialisation by ballooning of the a. carotis communis of rats. 3 experimental groups were established: group I received a standard diet; the diet of group II was supplemented with 2% cholesterol and group III received 2% cholesterol and 5% dried garlic powder. Four weeks after ballooning plasma cholesterol, the average thickness of the neointima as well as the DNA content and the expression of collagens type I, III and IV in the ballooned arterial segment were determined. Furthermore, the specific activities of the enzymes glutathione peroxidase, glutathione disulfide reductase, glutathione-S-transferase and glucose 6 phosphate dehydrogenase were measured in homogenates of liver, heart and aorta. Hypercholesterolemia induced by cholesterol-feeding (group II 92 +/- 18 mg/100 ml) was significantly reduced by garlic (group III 53 +/- 19 mg/100 ml). Only little effects of garlic were seen in inhibiting neointima after ballooning. However, significant effects were found in protecting the enzymes of the glutathione dependent peroxide detoxification system, which is strongly impaired under hypercholesterolemia. Generally a normalisation, in some cases even an improvement beyond that, of the enzyme activities occurred in the garlic treated group. This indicates that in the model of atherosclerosis used here garlic is effective in lowering plasma cholesterol and in improving peroxide detoxification, however, it has only little influence on the wound healing reaction and does not significantly inhibit the development of intimal thickenings after ballooning.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8024633&dopt=Abstract garlic



garlic
The effect of garlic extract on human metabolism of acetaminophen.

Gwilt PR, Lear CL, Tempero MA, Birt DD, Grandjean AC, Ruddon RW, Nagel DL.

College of Pharmacy, Eppley Institute, University of Nebraska Medical Center, Omaha 68131.

Several studies suggest that the constituents of garlic may inhibit experimentally induced carcinogenesis. To evaluate the chemopreventive properties of garlic in humans, the effects of chronic administration of an aged garlic extract on the disposition of acetaminophen and metabolites were studied. This commonly used drug was chosen because it forms a reactive electrophilic metabolite after oxidative metabolism. Sixteen subjects ingested daily doses of garlic extract (approximately equivalent to six to seven cloves of garlic) for 3 months. Before the course of garlic, at the end of each month and 1 month after termination of garlic administration, a 1-g oral dose of acetaminophen was given to each subject. Plasma and urine were measured for acetaminophen and the glucuronide, sulfate, cysteinyl, mercapturate, and methylthio metabolites. It was found that garlic treatment had no discernible effect on oxidative metabolism but was associated with a slight increase in sulfate conjugation of drug. These findings suggest that garlic extract has limited potential as a chemopreventive agent.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8049637&dopt=Abstract garlic