Abstract:

The lactobacillus extracted from homemade Sauerkraut juice was firstly biochemically identified for its bacterial species,, and then EPS extracted from the lactobacillus was determined by phenol-sulfuric acid method for its polysaccharide content. Based on single factor test, effects of temperature, pH value, glucose content, and experimental time on LAB EPS yield were studied by the orthogonal test with four factors at three different levels. The optimum conditions for high yield of extracellular polysaccharide in lactobacillus are as follows: 35 ℃, 1.5% mass fraction for glucose, pH 6.5, and 10 h fermentation.

Key words: lactobacillus, isolation and identification, optimization, extracellular polysaccharide