纳豆芽孢杆菌js-1固体发酵低温豆粕的工艺条件优化

以低温豆粕为原料,采用纳豆芽孢杆菌js-1固体发酵,以Fe3+还原力评价粗提物的抗氧化活性为指标进行发酵提取条件优化。首先从装量、基质含水量、接种量、发酵温度和发酵时间等5个因子中运用部分因子试验设计筛选出影响固体发酵条件的重要因素;然后在此基础上运用Box-Behnken的中心组合设计原理,采用响应面分析,对固体发酵进行条件优化;最后在单因素试验基础上运用正交试验设计对提取条件进行优化。最终的优化发酵提取条件为:基质含水量73%,接种量19%,发酵时间94.5 h,乙醇体积分数50%,液固比10∶1,提取时间90 min,提取3次。

Optimization fermentation and extraction technology of solid-state fermented low -temperature soybean meal by bacillus subtilis natto js-1

Optimization of fermentation and extraction technology of solid-state fermented low-temperature soybean pulp is by adopting bacillus subtilis natto js-1 by reducing power analyzing,and using the Fe3+ reducing power to assess the antioxidation power of crude extract.Fermentation conditions including filled ratio of shake bottle,substrate moisture content,inoculation,temperature and time were investigated.Firstly,the fractional factorial design was applied to screen the relatively important factors,from the conditions mentioned above,which affected the reducing power of the solid-state fermentation broth.Secondly,these important factors were optimized by Box-Behnken central composite design and by Response Surface analysis.Then,based on the optimized fermentation conditions,the single-factor experiment and orthogonal test design were adopted to optimize the extraction condition.The final optimized conditions obtained for fermentation and extraction are:substrate moisture content 73%,inoculation 19%,fermentation time 94.5 h,aqueous ethanol concentration 50%,liquid-solid ratio 10∶ 1,extraction time 90 min,and extracted 3 times.