Abstract: Dense cultivation is the key to prepare concentrated bacterial powder for vegetable fermentation. The study of high cell density culture of lactobacillus No. NCU 0101 has shown that it is feasible to achieve the goal using buffer solution, chemical neutralization and feed batch culture. It is found that medium formula, culture conditions, and feed batch methods have great impacts on biomass growth. Suitable medium formulation is: 5% glucose, 1% peptone, 0.5% K2HPO4, 0.3% sodium acetate. Optimal culture conditions are pH 6.3～5.8, temperature 30 ℃, oscillation frequency 40 r/min, and culture time 20 h. Appropriate feeding culture method is that 2.5% carbon and nitrogen sources (C/N ratio is 5:1) is added respectively after 0, 4 and 8 h. With the optimal culture conditions, the number of the bacteria cells is up to 7.83×109CFU/ml.

Key words: Lactobacillus, vegetable fermentation, high dense cultivation