earticle

영어

Lactic acid production was investigated using Lactobacillus paracasei KCTC 13169, L-lactic acid producer, for the feedstock of biopolymer. In batch cultures, glucose and yeast extract (YE) concentrations were varied in the range of 50-250 g/L and 5-15 g/L, respectively, in order
to determine maximum concentration and productivity of lactic acid as well as the optical purity of lactic acid during fermentation. Higher YE concentrations gave better cell growth affecting on the growthassociated lactic acid production so that the productivity of lactic acid increased up to more than 4 g/L.hr under 15 g/L of yeast extract. The maximum lactic acid concentration of more than 180 g/L was obtained when 250 g/L of glucose was fed while a high concentration of
glucose inhibited cell growth rate. Several kinds of fed-batch strategy including constant feeding, intermittent feeding, and pH-stat feeding were applied in order to increase the productivity and lactic acid concentration.