Abstract: Two Lactobacillus strains which had higher L-lactic acid yielding have been isolated and purified from the mixed cheese samples and fermented vegetable, and were identified by API bacterial identification system as Lactobacillus casei subsp. case and Lactobacillus casei subsp. rhamnosus. After fermentation in the culture consisted of following composition (g/L): glucose 85, lactose 45, yeastrel 5, peptone 10, NaCl 1.3, K2HPO4 1.5, MgSO4·7H2O 0.33, MnSO4 0.05 at 37 ℃ for 48 h, the yield of L-lactic acid are 56.50 g/L and 50.80 g/L, respectively.

Key words: L-lactic acid, Lactobacillus