| Glucosinolates and neutral detergent fiber are two important anti-nutritional factors that limit the feeding value of rapeseed meal. Fermentation is a good method to decrease the anti-nutritional factors in rapeseed meal. The mixed strains and inoculation ratio were optimized by prescreening, the second screening and mixing design. Identification medium of rapeseed meal was used in prescreening, then the degradation rates of glucosinolates and neutral detergent fiber, the growth curve and protease activity were comprehensively evaluated during the second screening. The inoculation ratio was optimized by simplex-centroid mixture design on the basis of the second screening, then the regression equation between factor and response value was fitted. The result showed that the optimal inoculation ratio was obtained as follows:Bacillus subtilis B3 46%, Bacillus natto N1 30% and Saccharomyces cerevisiae R1 24%. Under the optimal condition, the degradation rates of glucosinolates and neutral detergent fiber were 94.63% and 24.17% respectively. |
