Polak-Berecka Magdalena, Michalak-Tomczyk Magdalena, Skrzypczak Katarzyna, Michalak Katarzyna, Rachwał Kamila, Waśko Adam
Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, Skromna 8, 20-704 Lublin, Poland.
Department of Animal Physiology and Toxicology, Faculty of Science and Health, The John Paul II Catholic University of Lublin, Konstantynów 1H, 20-708 Lublin, Poland.
Foods. 2021 Nov 21;10(11):2877. doi: 10.3390/foods10112877.
This study is a brief report on the proteolytic activity of curly kale leaf extract against casein. Casein degradation products and an in silico analysis of the biological activity of the peptides obtained was performed. The efficiency of casein hydrolysis by curly kale extract was determined using SDS-PAGE and by peptide concentration determination. The pattern of the enzymatic activity was determined by MALDI-TOF MS analysis. The results showed that α- and β-casein were more resistant to curly kale extract hydrolysis, whereas κ-casein was absent in the protein profile after 8 h of proteolysis, and all casein fractions were completely hydrolyzed after 24 h of incubation. Based on sequence analysis, seven peptides were identified, with molecular mass in the range of 1151-3024 Da. All the peptides were products of β-casein hydrolysis. The identified amino acid sequences were analyzed in BIOPEP, MBPDB, and FeptideDB databases in order to detect the potential activities of the peptides. In silico analysis suggests that the β-casein-derived peptides possess sequences of peptides with ACE inhibitory, antioxidant, dipeptidyl peptidase IV inhibitory, antithrombotic, immunomodulatory, and antiamnesic bioactivity. Our study was first to evaluate the possibility of applying curly kale leaf extract to generate biopeptides through β-casein hydrolysis.
本研究是关于皱叶甘蓝叶提取物对酪蛋白的蛋白水解活性的简要报告。对酪蛋白降解产物以及所获得肽段的生物活性进行了计算机模拟分析。使用SDS-PAGE和肽浓度测定法确定了皱叶甘蓝提取物对酪蛋白的水解效率。通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）分析确定了酶活性模式。结果表明，α-酪蛋白和β-酪蛋白对皱叶甘蓝提取物的水解更具抗性，而在蛋白水解8小时后，κ-酪蛋白在蛋白质谱中消失，孵育24小时后所有酪蛋白组分均被完全水解。基于序列分析，鉴定出7种肽段，分子量在1151 - 3024 Da范围内。所有肽段均为β-酪蛋白水解产物。为了检测这些肽段的潜在活性，在BIOPEP、MBPDB和FeptideDB数据库中对鉴定出的氨基酸序列进行了分析。计算机模拟分析表明，源自β-酪蛋白的肽段具有具有血管紧张素转换酶（ACE）抑制、抗氧化、二肽基肽酶IV抑制、抗血栓形成、免疫调节和抗记忆缺失生物活性的肽段序列。我们的研究首次评估了应用皱叶甘蓝叶提取物通过β-酪蛋白水解生成生物活性肽的可能性。
