发酵紫苏粕制备抗氧化肽的工艺优化及抗氧化性

Process Optimization and Activity of Antioxidant Peptides Prepared from Fermented Perilla Meal

以脱脂后的紫苏炼油副产物紫苏粕为原料,选取酵母菌为发酵菌种,通过单因素和响应面试验探究紫苏粕发酵工艺对饼粕中蛋白质含量的影响,得到的优化条件为发酵液pH3.4、液料比5.0∶1(mL/g)、接菌量为8.5%(质量分数)、发酵时间24 h,此条件下蛋白质含量为0.679 mg/g。以最优条件下发酵后的紫苏粕酶解制备抗氧化肽,研究酶种类与酶用量对发酵后紫苏粕抗氧化性的影响。结果表明,发酵后紫苏粕蛋白经碱性蛋白酶水解后,其抗氧化能力强于胰蛋白酶水解后的酶解液,且当碱性蛋白酶的用量在5.0%(800 U/g)时,酶解液对DPPH自由基、羟基自由基、ABTS+自由基、超氧阴离子自由基清除能力达到最佳。

The defatted perilla meal,the by-product of perilla oil refining,was fermented with yeast.Single factor tests and response surface methodology were employed to optimize the fermentation process.The protein content reached the maximum of 0.679 mg/g when the fermentation was carried out with the liquid-to-material ratio of 5.0∶1(mL/g)and the inoculum amount of 8.5%(weight per unit volume)at pH3.4 for 24 h.Antioxidant peptide was prepared by enzymatic hydrolysis with the perilla meal fermented under the optimal conditions.The effects of enzyme type and enzyme amount on the antioxidant activity of fermented perilla meal were determined.The fermented perilla meal protein hydrolyzed by alkaline protease showed stronger antioxidant capacity than that hydrolyzed by trypsin.When the amount of alkaline protease was 5.0%(800 U/g),the hydrolysate showed the highest DPPH,hydroxyl,ABTS+,and superoxide anion radical scavenging abilities.