青刺果粕抗氧化肽的酶法制备工艺优化及体外抗氧化活性分析

Optimization of Enzymatic Preparation Process of Antioxidant Peptides from Prinsepia utilis Royle and Analysis of Their in Vitro Antioxidant Activities

摘要:

青刺果为食药同源的云南特色木本油料作物，其榨油后的副产物存在蛋白质利用率低的问题。实验以青刺果粕为原料获得具有抗氧化活性的蛋白酶解物，对酶质量分数、酶解时间、料液比三个因素进行单因素实验和响应面优化分析，确定碱性蛋白酶水解制备青刺粕蛋白酶解物的工艺条件。结果表明，最佳酶解工艺条件为：酶质量分数4.6%、酶解时间4.6 h、料液比1:31（g/mL），在此最优条件下酶解制备的抗氧化肽质量浓度为0.9 mg/mL时，对DPPH自由基、ABTS+自由基和羟基自由基的清除能力最高分别为76.46%、94.22%、73.02%。此外，青刺果抗氧化肽对细胞毒性实验结果表明，该肽对HepG 2细胞的生长无毒性作用。综上，该工艺条件下制备的青刺果抗氧化肽具有较好的抗氧化活性，研究可为青刺果蛋白资源的开发利用提供参考依据。

Abstract:

Prinsepia utilis Royle is a food and medicine homologous woody oil crop with Yunnan characteristics. The by-products after oil extraction have the problem of low protein utilization. In this experiment, Prinsepia utilis Royle meal was used as the raw material to produce protein hydrolysate with antioxidant activity. The single factor experiments and response surface optimization analysis were carried out on three factors, enzyme mass fraction, enzymatic hydrolysis time and solid-liquid ratio, to determine the enzymatic hydrolysis process conditions for the preparation of protease hydrolysate from Prinsepia utilis Royle meal by alkaline protease. The results showed that the optimal enzymatic hydrolysis conditions were: enzyme mass fraction, 4.6%; enzymatic hydrolysis time, 4.6 h; solid-liquid ratio, 1:31 g/mL. Under the optimal conditions, when the mass concentration of antioxidant peptide prepared by enzymatic hydrolysis was 0.9 mg/mL, the scavenging capacities for DPPH free radical, ABTS+ free radical and hydroxyl free radical were 76.46%, 94.22% and 73.02%, respectively. In addition, the results of cytotoxicity experiments showed that the peptide had no toxic effect on the growth of HepG 2 cells. Taken together, the antioxidant peptide prepared through this process had good antioxidant activity. This study can provide a reference for the development and utilization of Prinsepia utilis Royle protein resource.