Effect of Glycine on the Growth of Leuconostoc mesenteroides and Lactobacillus plantarum in Kimchi Fermentation

This study was aimed to investigate the effect of glycine supplementation on the growth of Leuconostoc mesenteroides and Lactobacillus plantarum during kimchi fermentation. As preliminary experiment, the effect of supplementation of glycine (0-2.0%, w/v) to MRS medium on the growth of Leuc. mesenteroides and L. plantarum was evaluated. At 2.0% glycine in the MRS medium, cell growth rate was inhibited by 79% for L. plantarum and 27% for Leuc. mesenteroides. Subsequently, different concentrations of glycine (0, 0.5, and 2.0%, w/v) were applied for kimchi fermentation for 21 days, at 5oC. At day 14, the pH and titratable acidity (TA) of kimchi supplemented with 2.0% glycine were 4.83 and 0.38%, respectively, whilst the control kimchi had a pH of 4.49 and TA of 0.44%, respectively. The ratio of Leuconostoc/Lactobacillus in kimchi increased as the concentration of glycine increased. The results show that the presence of glycine affected the growth of the 2 lactic acid bacteria, particularly of L. plantarum.