Effect of Derivatives of L-Cysteine on the Growth of Leuconostoc mesenteroides P-60.

1. Alliin and L-cystine disulfoxide stimulated the growth of Leuconostoc mesenteroides but to a lesser degree than L-cystine. 2. Substitution of the sulfur hydrogen of L-cysteine by alkyl and alkene radicals did not produce any observable response. The sulfoxide of S-ethyl-L-cysteine was also inactive; however, S-propyl-L-cysteine sulfoxide was found to have a very slight activity. 3. The activity of alliin may be due to both the presence of the sulfoxide group and the unsaturation in the allyl radical.