Antimicrobial activity of the thiosulfinates isolated from oil-macerated garlic extract

Three thilosulfinates were isolated from oil-macerated garlic extract, and their structures were identified as 2-propene-1-sulfinothioic acid S-(Z,E)- 1-propenyl ester [Alls(O)sPm-(Z,E)], 2-propenesulfinothioic acid S-methyl e ster [AllIS(O)SMe], and methanesulfinothioic acid S-(Z,E)-1-propenyl ester [MeS(O)SPn-(Z,E)]. This is the first report elf isolating these thiosulfina tes from oil-macerated garlic extract. Antimicrobial activities of AllS(O)S Pn(Z,E) and AllS(O)SMe against Gram-positive and negative bacteria and yeas ts were compared with Z-propene-1-sulfinothioic acid S-2-propenyl ester [Al lS(O)SAll, allicin] which is well-known as the major thiosulfinate in garli c. Antimicrobial activity of AllS(O)SMe and AllS(O)SPn-(Z,E) were comparabl e and inferior to that of allicin, respectively. This result suggested that the antimicrobial activity of 2-propene sulfinothioic acid S-alk(en)yl est ers were affected by alk(en)yl groups. The order for antimicrobial activity was: allyl greater than or equal to methyl > propenyl.