ABSTRACT
Response surface analysis (uniform precision of central composite design, SAS 9.1.3 software) was applied to optimize the four major factors (ratio of soybean meal to water, enzyme quantity, fermentation time and inoculation quantity) for soybean meal solid fermentation. According to the change of the hydrolyzation degree of soybean protein, the equation of polynomial regression was established between those factors and the response. The result showed that the optimum condition included as follows: ratio of soybean meal to water 1∶1.00,enzyme quantity 2.55%, fermentation time 65h and inoculation quantity 1.00%. Under the optimum level, the degree of hydrolyzation reached 13.3%, which increased 56% over pre-optimization.
ABSTRACT
ObjectiveTo investigate the inhibitory effect of polysaccharides from Sargassum fusiforme on the HepG 2 cells. Methods Six kinds of polysaccharides were prepared by hot water extracting, ethanol and CaCl 2 precipitating and acid hydrolyzing. Inhibition rate of these polysaccharides on the HepG 2 cells were determined by MTT bioassay. Results Inhibition rate of two kinds of polysaccharides increased at lower concentration. Inhibition ratie of other polysaccharides increased with the increment of concentration. At the dose less than 2000mg?L -1,inhibition rate was not more than 40%. Conclusion All polysaccharide specimens obtained from Sargassum fusiforme have some inhibitory effects on human liver cancer cells HepG 2.