Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology & Business Univ. (BTBU), Beijing, 100048, China.
Department of Biological Sciences, National University of Medical Sciences, The Mall, Rawalpindi, 46000, Pakistan.
J Food Sci. 2020 Apr;85(4):1045-1059. doi: 10.1111/1750-3841.15063. Epub 2020 Feb 28.
Highland barley brewer's spent grain (BSG), being China's brewing industry's major by-product is the focus of current research. The aim of the present study was to scrutinize the effects of ultrasound and heat pretreatments on enzymatic hydrolysis of highland barley BSG protein hydrolysates (HBSGPH) and evaluate the effect of enzymatic hydrolysis time on the antioxidant activity of hydrolysates by Alcalase. Different ultrasonic waves (40 and 50 kHz) and heat pretreatment temperatures (50 and 100 °C) were chosen and the pretreatment time was 15, 30, and 60 min. The obtained results revealed that the ultrasound pretreatment of highland barley BSG protein at 40 and 50 kHz has significantly (P < 0.05) enhanced about 57 and 67% of oxygen radical absorption capacity of obtained hydrolysate over the untreated substrate. The 1,1-diphenyl-2-picrylhdrazl (DPPH) radical scavenging activity (DRSA) 28%, metal chelating activity (MCA) 54%, superoxide radical scavenging activity (SRSA) 18%, and hydroxyl radical scavenging activity (HRSA) 25% of HBSGPH at 50 kHz were also improved (P < 0.05) significantly. HBSGPH from heat treatment at 100 °C showed no SRSA and HRSA scavenging activities but improved significantly (P < 0.05) about 27% ferric reducing antioxidant power (FRAP) assay values. In the present work, the resultant HBSGPH had stronger antioxidant properties with ultrasound pretreatment at 50 kHz and the enzymatic hydrolysis after 4 hr was facilitating the enzymatic release of antioxidant peptides from HBSGPH. PRACTICAL APPLICATION: Highland barley BSG is attracting toward natural food products due to its potent natural antioxidants to overcome the risk of diseases and are beneficial for human health.
青稞酒糟粕（BSG）是中国酿造业的主要副产物，是当前研究的重点。本研究旨在研究超声和热预处理对青稞 BSG 蛋白水解物（HBSGPH）酶解的影响，并通过 Alcalase 评价酶解时间对水解物抗氧化活性的影响。选择了不同的超声波（40 和 50 kHz）和热预处理温度（50 和 100°C），预处理时间为 15、30 和 60 min。结果表明，在 40 和 50 kHz 下超声预处理青稞 BSG 蛋白，与未处理的底物相比，所得水解物的氧自由基吸收能力显著提高了约 57%和 67%。1,1-二苯基-2-苦基肼（DPPH）自由基清除活性（DRSA）28%、金属螯合活性（MCA）54%、超氧自由基清除活性（SRSA）18%和羟基自由基清除活性（HRSA）25%的 HBSGPH 也显著提高（P < 0.05）。在 100°C 下热处理的 HBSGPH 没有 SRSA 和 HRSA 清除活性，但铁还原抗氧化能力（FRAP）测定值显著提高（P < 0.05）约 27%。在本工作中，用 50 kHz 超声预处理得到的 HBSGPH 具有更强的抗氧化性能，酶解 4 小时后有利于从 HBSGPH 中释放出抗氧化肽。实用程序：青稞 BSG 因其具有强大的天然抗氧化剂而受到天然食品的青睐，可克服疾病风险，有益于人类健康。
