基于单纯形-重心设计的菜籽粕生物改良菌株的复配研究

摘要

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 fac-tors in rapeseed meal. The mixed strains and inoculation ratio were optimized by prescreening, the sec-ond 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 sim-plex-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.%硫甙和中性洗涤纤维是限制菜籽粕饲用的两个重要抗营养因子。发酵法是降低菜籽粕抗营养因子的重要手段。通过初筛、复筛和混料设计，优选了混合菌发酵菌株和接种比例。在初筛中采用菜籽粕鉴定培养基，在复筛中对硫甙降解率、中性洗涤纤维降解率、生长曲线和蛋白酶酶活进行综合评价，在复筛的基础上采用单纯形-重心设计进行菌株配比的优化，拟合出因素与响应值之间的回归方程，得到优化的菌株接种比例为枯草芽孢杆菌B346%、纳豆芽孢杆菌N130%、酿酒酵母R124%，在此条件下进行发酵试验，硫甙、中性洗涤纤维的降解率分别为94．63%、24．17%。