为实现青稞酒糟的高值化利用，该研究在提取青稞酒糟蛋白基础上，以DPPH自由基清除率和还原力为指标优化了青稞酒糟蛋白酶解液的制备工艺，并对该酶解液的体外抗氧化活性和细胞保护作用进行了探究。结果表明：青稞水酒糟和青稞白酒糟均含有丰富的蛋白质，含量分别为31.46 g/100 g和18.47 g/100 g；超声纤维素酶法辅助碱提酸沉法对青稞水酒糟的蛋白提取率高达76.10%（m/m），白酒糟的为29.88%；碱性蛋白酶最适合用于青稞水酒糟蛋白的酶解，其最佳酶解条件为：料液比1:60（m/V），超声时间15 min，酶添加3.7%（m/m）及酶解时间3.5 h，此条件下制得的青稞水酒糟蛋白酶解液的DPPH自由基清除率高达95.02%；不同浓度的青稞水酒糟蛋白酶解液对HepG2细胞活力没有负面影响；随着青稞水酒糟蛋白酶解液浓度的升高，对经H2O2 诱导的细胞内ROS逐渐降低，酶解液浓度为5.0 mg/mL（m/V）时可使受损细胞内的ROS比损伤组低约50%。该研究成果可为青稞水酒糟蛋白酶解液的制备及其在保健食品、化妆品中的高值化利用提供参考。

To illustrate the high-value utilization of highland barley brewer’s spent grains, the process used to prepare its protease hydrolysate was optimized based on protein extraction from highland barley brewer’s spent grains using the DPPH free radical scavenging rate and reducing power as indicators. Thereafter, the in vitro antioxidant activity and cytoprotective effects of the hydrolysates were examined. The soluble and white highland barley brewer’s spent grains were found to be rich in protein, with protein contents of 31.46 g/100 g and 18.47 g/100 g, respectively. Using the ultrasound/cellulase-assisted alkali extraction and acid precipitation method, the protein extraction rates from the soluble and white highland barley brewer’s spent grains were 76.10% (m/m) and 29.88%, respectively. Alkaline protease was found to be most suitable for enzymatic hydrolysis of the proteins of soluble highland barley brewer’s grains. The optimal enzymatic hydrolysis conditions were as follows: solid to liquid ratio, 1:60 (m/V); ultrasonic treatment time, 15 min; enzyme dosage, 3.7% (m/m); and enzymatic hydrolysis time, 3.5 h. Under these conditions, the DPPH free radical scavenging rate of the protease hydrolysate of soluble highland barley brewer’s spent grains reached 95.02%. Different concentrations of the protease hydrolysate of soluble highland barley brewer’s spent grains did not exhibit negative effects on HepG2 cell viability. In addition, as the concentration of the protease hydrolysate of soluble highland barley brewer’s spent grains increased, ROS in cells damaged by H2O2 gradually decreased. In fact, 5.0 mg/mL (m/V) of the protease hydrolysate reduced ROS in damaged cells by approximately 50%. In addition to serving as a reference, this study provides a theoretical basis for preparing the protease hydrolysate of soluble highland barley brewer’s spent grains and illustrates its high-value utilization in healthy food and cosmetics.

上海市崇明区科委农业科技攻关项目（CK2022-52）；广州市名师工作室（2022MSGZS015）；广州市大学生创新创业训练计划项 目（2022CXCYJH013）