Abstract: In this study, the one-factor-at-a-time method was employed to determine that the optimum carbon source for
liquid-core microcapsules of Lactobacillus brevis M3-3 as a dominant strain isolated from Xinjiang traditional fermented
camel milk was sucrose at 15 g/L, the optimum nitrogen source was typtone at 10 g/L, the optimum growth promoting
factor was corn steep liquor at 15% and the optimum pH buffering agent was CaCO3 at 5 g/L. The interaction among the
four factors was studied using response surface methodology to determine their optimum levels. The optimum medium
formulation for high-density cultivation of the strain was found to be composed of 60 g/L whey powder, 18 g/L sucrose,
13.02 g/L typtone, 130 mL/L corn steep liquor, and 3.29 g/L CaCO3.

Key words: traditional fermented camel milk, Lactobacillus brevis, high-density cultivation, response surface methodology