豆粕源抗氧化肽的制备、鉴定与活性表征

Preparation,Identification and Activity Characterization of Antioxidant Peptides from Soybean Meal

豆粕作为豆油加工的主要副产物,含有大豆中几乎全部蛋白质,具有广阔的应用前景。本研究中以大豆粕为原料,利用超声辅助酶解制备豆粕抗氧化肽,通过单因素和响应面实验,确定出最佳工艺参数为:酶解pH 8.0、底物质量分数9%、加酶量6665.39 U/g、酶解温度50℃、酶解时间4.0 h、超声时间9 min、超声功率300 W。经超滤处理获得相对分子质量<1000的组分,并将该组分通过液相色谱串联二级质谱(LC-MS/MS)鉴定,获得豆粕源抗氧化五肽,氨基酸序列为Ile-Trp-Asn-Leu-Asn(IWNLN),其ABTS自由基清除能力的IC50值为(0.060±0.003)mg/mL,ORAC值为(7.614±0.138)mg TE/mg,羟自由基清除能力的IC50值为(0.008±0.001)mg/mL。本研究为豆粕抗氧化肽生产工艺优化和功能因子序列确证提供了实验基础,为豆粕蛋白肽功能产品开发提供新的思路。

Soybean meal,the main by-product of soybean oil processing,contains almost all the proteins in soybeans and has broad application prospects.In this study,soybean meal antioxidant peptides were prepared from ultrasonic-assisted enzymatic hydrolysis.Through single factor and response surface tests,the optimum technological parameters were determined as follows:substrate concentration of 9%(mass fraction),enzyme amount of 6665.39 U/g,enzyme hydrolysis at pH 8.0 under 50℃for 4.0 h and ultrasound for 9 min under 300 W.The components with molecular weight less than 1000 were obtained through ultrafiltration membrane and identified by LC-MS/MS.An antioxidant pentapeptide from soybean meal was obtained.Its amino acid sequence was Ile-Trp-Asn-Leu-Asn(IWNLN),and the IC50 value of ABTS radical scavenging ability was(0.06±0.003)mg/mL.At a concentration of 0.01 mg/mL,the ORAC value was(7.614±0.138)mg TE/mg,and the IC50 value of hydroxyl radical scavenging ability was(0.008±0.001)mg/mL.This study provides an experimental basis for the optimization of production process and the confirmation of functional factor sequence of soybean meal antioxidant peptide,and provides a new idea for the development of soybean meal protein peptide functional products.