主要研究了枯草芽孢杆菌1398发酵制备大豆肽的工艺条件。以大豆肽含量和平均肽链长度为指标,通过对蔗糖添加量、水分添加量、接种量、发酵温度、发酵时间的单因素实验和正交实验,确定了发酵法制备大豆肽的最优工艺条件:蔗糖添加量0.5%,水分添加量70%,接种量2.0%,32℃条件下发酵32 h。此条件下测得短肽含量为252.95 mg/g。初步提纯后,粗肽的DPPH.,O2-.和.OH清除能力较市售肽分别提高了119.53%,26.02%,65.56%。实验结果表明,发酵工艺能够显著提高产物的大豆肽含量及抗氧化能力。

An optimization of parameters in fermentation process of soybean protein by Bacillus subtitles 1398 and antioxidant activity of fermented peptides were studied.With the soybean peptides content and average peptide chain length as index,through single-factor and orthogonally experiment of additive amount of sucrose and water,inoculum dose,fermentation temperature and time,the optimal fermentation methods were obtained under the conditions of 0.5% of sucrose,2.0% of inoculum dose,60% of water,32℃ of fermentation temperature,and 32h of fermentation time.Under the optimized fermentation conditions,peptides content reached 252.95 mg/g.After preliminary purification,The inhibition rate to DPPH·,O2-· and ·OH of fermented peptides increased 119.53%,26.02% and 65.56% to merchant peptides,respectively.The result indicated that fermentation process was helpful for improving peptides content and antioxidant activity of hydrolyzed protein.