Allicin

The esters of thiosulfinic acid R -SO,-S-R are used as fungicides and antibacterial prepai ations. These compounds have similar stiaicture fragments to allicin - natural insecticide from garlic with following structure (CH =CH-CH ),[SO-S] (http //www.ALLICIN.com). For deter-mination of ethyl S-ester of 4-aminobenzenthiosulfinic acid (esulan) in the ointment RP-HPLC was proposed [1] with acetonitrile water=30 70 as eluent. For seai ching bioactive compounds the synthesis of new esters of thiosulfinic acid is perspective that was confirmed by results of recent studies as instance [2]. Therefore requirements ai e existed for investigation HPLC sepai ations of these substances. 

Allicin is responsible for the distinctive taste and odor of garlic Its simple formula is C6H10O2S. How many grams of sulfur can be obtained from 25.0 g of allicin ... 

Allicin 1. 3-Acetyl-6- methoxybenz- aldehyde 1. Ethylene 1. Decomposition products of amygdalin... 

Enteric-coated tablets or capsules of garlic are better absorbed since an active ingredient, allicin, is acid labile. The tablets or capsules bypass the stomach and release their contents in the alkaline medium of the small intestine [4],... 

Scheme 10 The formation of allicin from alliin by alliinase action...

Garlic supplements - powder tablets or capsules, steam-distilled oil, vegetable oil macerate extract, or extract aged in dilute alcohol - are widely available and are taken by millions. Since the active principle, allicin, is not present in garlic bulb, the supplements rely on the presence of precursor alliin and enzyme alliinase. In tests on 24 commercial brands of enteric-coated tablets, all except one gave low dissolution allicin release 83% of the brands released less than 15% of their potential allicin.78,79 Relevant factors were impaired enzyme activity caused by excipients and slow tablet disintegration. Caveat emptor ... 

Ajoene (Spanish, ajo, garlic), 4,5,9-trithiadodeca-l,6,ll-triene-9-oxide 35 (Scheme 12), an antithrombotic compound with other well-defined physiological properties, is formed from allicin.84 Like allicin, ajoene is a sulfoxide but has two further sulfur atoms in a disulfide linkage. E and Z isomeric forms are possible involving the C=C bond at positions 6 and 7. Ajoene is somewhat more stable than allicin. The formation of ajoene probably involves condensation of 2 molecules of allicin forming a sulfonium salt 33, with elimination of propenesulfenic acid. Elimination of a second molecule of propenesulfenic acid... 

Constituents that have some known pharmacological activity that contributes to some extent to the efficacy of the product have been identified. These are known as active markers. An example of this category is alliin, which is converted to allicin in presence of allinase enzyme, and is present in garlic. These active markers may or may not have clinically proven efficacy in their own right. A minimum content or range for active markers is usually specified in pharmacopeial articles. A quantitative determination of active marker(s) during... 

Allin is converted to allicin by an enzyme known as allinase when garlic is mashed (as recommended by many Italian cooks) rather than just cut ... 

Note that we have something new here a sulfur-sulfur bond. Allicin is a disulfide. Finally, allicin is converted to a molecule largely responsible for garlic breath — dipropenyl disulhde ... 

Ajoene is formed from three molecules of allicin and is responsible in part for the... 

Garlic clearly has antithrombotic properties. Ajoene (an allicin metabolite) and methyl allyl trisulfide inhibit platelet aggregation. Garlic may promote vasodilation by relaxing smooth muscle, and it may reduce low-density lipoprotein (LDL) oxidation. 

Garlic can cause heartburn, nausea, and loose stools at high doses, especially in those unaccustomed to it. Its most characteristic and troublesome side effect, however, is persisting breath odor, which no amount of tooth brushing will eradicate. Allicin and its odoriferous metabolic products are actually released into the lung alveoli and exhaled. 

Formula, Natrol) used in the garlic-saquinavir study described above (41). In the study by Gurley et al. (39) garlic oil 500 mg did not result in appreciable differences in the 1-hydroxymidazolam/midazolam phenotypic ratio for CYP3A4, the enzyme that mediates the metabolism of saquinavir. Both studies administered the garlic preparations for at least three weeks, and therefore it is unlikely that the duration of therapy would account for the difference between studies. On the other hand, if allicin content is a critical issue, it may be that one of the reasons for the conflicting results between the two studies is potential variability in this active constituent in the two garlic preparations used. 

GarlicPure Maximum Allicin Formula, twice daily for 20 days Healthy volunteers Saquinavir, 1200 mg three times daily None Reduced AUC, Cmaxj and Cjjiin of saquinavir Possible induction of CYP3A4... 

Finally, even if all garlic preparations were standardized to allicin content, currently the standardization practices and therefore the standardized content can vary significantly from one manufacturer to another, while product inconsistency has not been demonstrated for garlic preparations, there is literature data on the disparity of constituent content among different echinacea products (20) and ginseng products (21) (refer to Chapter 2 for further details). As such, the choice of a specific botanical product or preparation may make a difference in the presence and magnitude of a botanical product rug interaction. 

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