酶解豆清液制备生物活性多肽工艺优化及抗氧化能力研究

Optimization of enzymatic hydrolysis of soybean clear liquid for preparation of biologically active peptides and its antioxidant capacity

目的探究木瓜蛋白酶水解豆清液制备生物活性多肽的最佳工艺条件,评价该生物活性多肽的抗氧化能力。方法以三氯乙酸-双缩脲法测得的多肽产率为参考指标,在单因素实验结果基础上,通过响应面实验确定酶解豆清液的最优酶解条件,并通过测定2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐[2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate),ABTS]、 1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率,分析豆清多肽的抗氧化活性。结果最佳酶解条件为:木瓜蛋白酶添加量2.0%、酶解pH5.0、酶解温度53℃、酶解时间7h,在该条件下豆清液的多肽产率为115.50%,在预测值范围内。抗氧化实验测得VC(维生素C,vitamin C)与样品对ABTS自由基清除能力的半最大效应浓度(concentration for 50% of maximal effect,EC_(50))值分别为0.003、1.871 mg/mL,对DPPH自由基清除能力EC_(50)值分别为0.006、6.459mg/mL,说明样品具有一定的抗氧化能力。结论木瓜蛋白酶水解豆清液制备生物活性多肽不仅能降低豆清液排放,而且为提高豆清液附加值提供了技术支撑,同时也为豆清液生物活性多肽的多元化使用提供来源。

Objective To explore the best technological conditions for the preparation of biological active peptides by papain enzymatic hydrolysis of soybean clear liquid,and evaluate the antioxidant capacity of the biologically active peptides.Methods The peptides yield measured by the trichloroacetic acid-biuret method was the reference index.Based on the results of single-factor experiments,the optimal enzymatic conditions for enzymatic hydrolysis of soybean clear liquid were determined by response surface experiments.The antioxidant activity of soybean clear peptides was analyzed by measuring the free radical scavenging rate of 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate)(ABTS) and 1,1-diphenyl-2-picrylhydrazyl(DPPH).Results The best enzymolysis conditions:Papain addition amount 2.0%,enzymolysis pH 5.0,enzymolysis temperature 53 ℃,enzymolysis time 7 h.Under these conditions,the peptides yield of soybean clear liquid was 115.50% within the predicted value range.The antioxidation experiment measured that the concentration for 50% of maximal effect(EC_(50)) values of VC(vitamin C) and the sample for ABTS free radical scavenging ability were 0.003,1.871 mg/mL,and the EC_(50) values of DPPH free radical scavenging ability were 0.006,6.459 mg/mL,indicating that the sample had certain antioxidant capacity.Conclusion Papain enzymatically hydrolyze of soybean clear liquid to prepare biologically active peptides not only reduces the discharge of soybean liquid,but also provides technical support for increasing the added value of soybean clear liquid.At the same time,it provides source for the diversified use of soybean clear liquid biologically active peptides.