模拟胃肠道消化对玉米低聚肽抗氧化作用的影响

Effect of Simulated Gastrointestinal Digestion on Antioxidant Activity of Corn Oligopeptides

摘要:

以胃蛋白酶和胰蛋白酶在体外模拟胃肠环境，测定模拟消化前后玉米低聚肽的相对分子质量分布、DPPH自由基清除能力、·OH清除能力、ABTS自由基清除能力、ORAC值和ROS清除能力，旨在探索模拟胃肠道消化对玉米低聚肽抗氧化活性的影响。结果表明：玉米低聚肽中大部分肽段相对分子质量低于1 000。分别模拟胃、肠环境消化后，重均相对分子质量有所下降，下降率分别为1.47%、0.05%，ABTS自由基清除能力有一定程度的升高，分别为25.47%、1.39%。模拟胃环境消化前后，DPPH自由基清除能力IC50值分别约为1.41、1.50 mg/mL，·OH清除能力IC50值分别约为10.3、12.3 mg/mL；模拟肠环境消化前后，DPPH自由基清除能力IC₅₀值分别约为1.39、1.48 mg/mL，·OH清除能力IC₅₀值分别约为8.1、9.5 mg/mL。模拟胃环境消化后，ORAC值有所降低，降幅为10.4%，100、400 μg/mL玉米低聚肽对ROS清除能力分别提高了1.42%、16.78%；模拟肠环境消化后，ORAC值提高了1.4%，100 μg/mL玉米低聚肽对ROS清除能力降低1.71%，而400 μg/mL玉米低聚肽对ROS清除能力提高2.61%。

Abstract:

The molecular weight distribution, DPPH radical scavenging ability, ·OH scavenging ability, ABTS radical scavenging ability, ORAC value and ROS scavenging ability of corn oligopeptides (COPs) before and after simulated digestion by pepsin and trypsin in vitro were measured, in order to explore the effect of simulated gastrointestinal digestion on the antioxidant activity of COPs. The results showed that the relative molecular weight of most peptides in COPs was less than 1000 u. After simulated gastric and intestinal digestion, the weight average molecular weight decreased by 1.47% and 0.05%, respectively, and the free radical scavenging capacity of ABTS increased to a certain extent, 25.47% and 1.39%, respectively. Before and after digestion in simulated gastric environment, the IC50 values of DPPH free radical scavenging capacity were about 1.41 and 1.50 mg/mL, and the IC50 values of ·OH scavenging capacity were about 10.3 and 12.3 mg/mL, respectively. Before and after digestion in simulated intestinal environment, the IC₅₀ values of DPPH free radical scavenging capacity were about 1.39 and 1.48 mg/mL respectively, and the IC₅₀ values of ·OH scavenging capacity were about 8.1 and 9.5 mg/mL, respectively. After simulated gastric digestion, ORAC value decreased by 10.4%, and ROS scavenging ability of 100 μg/mL and 400 μg/mL COPs increased by 1.42% and 16.78%, respectively. After simulated intestinal digestion, ORAC value increased by 1.4%, ROS scavenging activity of 100 μg/mL COPs decreased by 1.71%, and ROS scavenging activity of 400 μg/mL COPs increased by 2.61%.