Rathnapala Ethige Chathura Nishshanka, Ahn Dong Uk, Abeyrathne Edirisingha Dewage Nalaka Sandun
Department of Animal Science, Uva Wellassa University, Badulla 90000, Sri Lanka.
Department of Animal Science, Iowa State University, Ames IA 50011, USA.
Food Sci Anim Resour. 2021 Jul;41(4):608-622. doi: 10.5851/kosfa.2021.e19. Epub 2021 Jul 1.
Bioactive peptides have great potentials as nutraceutical and pharmaceutical agents that can improve human health. The objectives of this research were to produce functional peptides from ovotransferrin, a major egg white protein, using single enzyme treatments, and to analyze the properties of the hydrolysates produced. Lyophilized ovotransferrin was dissolved in distilled water at 20 mg/mL, treated with protease, elastase, papain, trypsin, or α-chymotrypsin at 1% (w/v) level of substrate, and incubated for 0-24 h at the optimal temperature of each enzyme (protease 55°C, papain 37°C, elastase 25°C, trypsin 37°C, α-chymotrypsin 37°C). The hydrolysates were tested for antioxidant, metal-chelating, and antimicrobial activities. Protease, papain, trypsin, and α-chymotrypsin hydrolyzed ovotransferrin relatively well after 3 h of incubation, but it took 24 h with elastase to reach a similar degree of hydrolysis. The hydrolysates obtained after 3 h of incubation with protease, papain, trypsin, α-chymotrypsin, and after 24 h with elastase were selected as the best products to analyze their functional properties. None of the hydrolysates exhibited antioxidant properties in the oil emulsion nor antimicrobial property at 20 mg/mL concentration. However, ovotransferrin with α-chymotrypsin and with elastase had higher Fe-chelating activities (1.06±0.88%, 1.25±0.24%) than the native ovotransferrin (0.46±0.60%). Overall, the results indicated that the single-enzyme treatments of ovotransferrin were not effective to produce peptides with antioxidant, antimicrobial, or Fe-chelating activity. Further research on the effects of enzyme combinations may be needed.
生物活性肽作为营养保健品和药物制剂具有巨大潜力，可改善人类健康。本研究的目的是使用单一酶处理从卵转铁蛋白（一种主要的蛋清蛋白）中制备功能性肽，并分析所产生水解产物的特性。将冻干的卵转铁蛋白以20mg/mL的浓度溶解于蒸馏水中，以1%（w/v）的底物水平用蛋白酶、弹性蛋白酶、木瓜蛋白酶、胰蛋白酶或α-胰凝乳蛋白酶处理，并在每种酶的最佳温度（蛋白酶55°C、木瓜蛋白酶37°C、弹性蛋白酶25°C、胰蛋白酶37°C、α-胰凝乳蛋白酶37°C）下孵育0-24小时。对水解产物进行抗氧化、金属螯合和抗菌活性测试。孵育3小时后，蛋白酶、木瓜蛋白酶、胰蛋白酶和α-胰凝乳蛋白酶对卵转铁蛋白的水解效果相对较好，但弹性蛋白酶需要24小时才能达到类似的水解程度。将与蛋白酶、木瓜蛋白酶、胰蛋白酶、α-胰凝乳蛋白酶孵育3小时后以及与弹性蛋白酶孵育24小时后获得的水解产物选为最佳产物，以分析其功能特性。在20mg/mL浓度下，所有水解产物在油乳液中均未表现出抗氧化性能，也没有抗菌性能。然而，用α-胰凝乳蛋白酶和弹性蛋白酶处理的卵转铁蛋白比天然卵转铁蛋白具有更高的铁螯合活性（1.06±0.88%，1.25±0.24%）（天然卵转铁蛋白为0.46±0.60%）。总体而言，结果表明卵转铁蛋白的单一酶处理对于产生具有抗氧化、抗菌或铁螯合活性的肽并不有效。可能需要进一步研究酶组合的效果。
