Onion organosulfur compounds

SPARNINS V L, BARANY G, WATTENBERG Lw. (1988) Effects of organosulfur compounds from garlic and onions on benzo[a]pyrene-induced neoplasia and glutathione S-transferase activity in the mouse. Carcinogenesis. 9 131-4. 

Organosulfur compounds present inAllium vegetables, which are either lipid or water soluble, are considered responsible for the beneficial effects of these herbs. Garlic derivatives generally have a thioallyl moiety, whereas onion extracts contain a thiopropyl group with somewhat different chemical properties [14]. 

Many organosulfur compounds undergo biological oxidation at the sulfur atom to yield products which have pronounced physiological activity or serve as intermediates in generating bioactive compounds. Three examples are the lachrymating agent in onions ( ) (1), the oxo intermediate ( ) in metabolic desulfuration of phosphorothionate insecticides to form potent cholinesterase inhibitors (2), and the sulfoxides QJ produced on metabolism of thiocarbamate herbicides (3). 

Takada N, Matsuda T, Otoshi T, et. al. Enhancement by organosulfur compounds from garlic and onions of diethylnitroasamine-induced glutathione S-transferase positive foci in the rat liver. Cancer Res 1994 54 2895-9. 

A similar study employing onion juice showed SFE to be ca. 69% as efficient as conventional organic solvents for extracting the major organosulfur compounds (28). The diminished efficiency of SFE for onion compared with garlic may be due to... 

Munday R, Munday CM. Relative activities of organosulfur compounds derived from onions and garlic in increasing tissue activities of quinone reductase and glutathione transferase in rat tissues. Nutr Cancer 2001 40 205-210. 

Fukushima, S. Takada, N. Hori, T. Wanibuchi, H., Cancer prevention by organosulfur compounds from garlic and onion. Journal of Cellular Biochemistry (1997) 100—105. 

Fig. 1.3 Major thiosulfinate compounds found in AUiaceae family (a) organosulfur compounds in intact plants, (b) compounds Produced from allyal cystein sulfoxide (in garlic) and (c) 1-propenyl cystein sulfoxide (in onion) by aUinase...

Benkeblia N (2004) Antimicrobial activity of essential oil extracts of various onions (Allium cepa) and garhc (Allium sativum). LWT- Food Sci Technol 37 263-268 Benkeblia N, Lanzotti V (2007) Allium thiosulfinates chemistry, biological properties and their potential utihzation in food preservation. Food 1(2) 193-201 Bianchini F, Vainio H (2001) Allium vegetables and organosulfur compounds do they help prevent cancer. Environ Health Perspect 109(9) 893-902 Block E (1985) The chemistry of garhc and onion. Sci Am 252 114-119... 

These are respectively the 5-oxides and 5-dioxides of thiocarbonyl compounds. The lachrymatory factor of onions was shown to be (Z)-propanethial 5-oxide (R1 = Et, R2 = H), and a good deal of the chemistry of sulfines was carried out in connection with the study of the organosulfur chemistry of alliaceous plants [186]. 

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