Garlic compounds

Figure 6 Typical garlic compounds. Transformation into different compounds depends on the chemical nature of the solvent.

There are only a few reports on the absorption, metabolism, and excretion of garlic s sulfur compounds available. Further, until now it is not known what metabolic form of allicin actually reaches the target cells, and it is still unknown how garlic compounds might function in the body. 

Recently, Germain et al. (90) studied the in vivo metabolism of diallyl disulfide (DADS), a garlic compound claimed to have anticarcinogenic effects. After oral administration of a single dose of 200mg/kg, metabolites were measured in the stomach, liver, plasma, and urine by GC coupled with MS over 15 days. DADS was detected in almost all analyzed tissues within the first hours. In addition, the metabolites allylmercaptan (AM) and allyl methyl sulfide (AMS) were detected. The Cmav of the metabolites were higher than that of DADS (1.46 pg/mL). The %ax for DADS was estimated to be less than one hour, whereas this time increased to 24 hours for AM and AMS (90). 

Garlic oil and S-allyl-cysteine sulfoxide (Alliin), a garlic compound, exhibited similar antioxidant properties. Aged garlic extract prevents ischemia and reperfusion injuries to the heart and brain. 

In onions, things start much the same way but the initial amino acid is not quite the same. The skeleton is the same as that of the garlic compound but the double bond is conjugated with the sulfoxide. Elimination and dimerization of the sulfenic acid produce an isomeric thiosulfinate. 

Lau BHS, Yamasaki T, Gridley DS. Garlic compounds modulate macrophage and T-lymphocyte functions. Mol Biother 1991 3 103-107. 

Nagae S, Ushijima M, Hatono S, et al. Pharmacokinetics of the garlic compound S-allylcysteine. PlantaMed 1994 60 214-217. 

Based on the predictions of the ETSA some new garlic compounds have been synthesized. This work will be reported in due course. 

Chung JG, Chen GW, Wu LT, Chang HE, Ein JG, Yeh CC, Wang TF. Effects of garlic compounds diallyl sulfide and diallyl disulfide on arylamine N-acetyltransferase activity in strains of Helicobacter pylori from peptic ulcer patients. Am J Chin Med 1998 26 353-364. 

Welch C, Wuarin L, Sidell N. Antiproliferative effect of the garlic compound Sallyl cysteine on human neuroblastoma cells in vitro. Cancer Lett 1992 63 211-219. 

Peng, Q., Buz Zard, A.R., and Lau, B.H., Neuroprotective effect of garlic compounds in amyloidbeta peptide-induced apoptosis in vitro, Med. Set Monit., 8, BR328, 2002. 

Lau BH (2006) Suppression of LDL oxidation by garlic compounds is a possible mechanism of cardiovascular health benefit. J Nutr 136(3 Suppl) 765S-768S... 

Lawson LD, Wang ZJ (2005) Allicin and allicin-derived garlic compounds increase breath acetone through allyl methyl sulfide use in measuring allicin bioavailability. J Agric Food Chem 53(6) 1974-1983. doi 10.1021/jf048323s... 

Pushpendran CK, Devasagayam TP, Chintalwar GJ, Banerji A, Eapen J (1980) The metabolic fate of [35S]-diallyl disulphide in mice. Experientia 36(8) 1000-1001 Nagae S, Ushijima M, Hatono S, Imai J, Kasuga S, Matsuura H, Itakura Y, Higashi Y (1994) Pharmacokinetics of the garlic compound S-allylcysteine. Planta Med 60(3) 214-217. 

Lawson, L.D. and Wang, Z.J. 2005. Allicin and aflicin-derived garlic compounds increase breath... 

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