Protein Chemistry and Bioactive Peptides Laboratory, Department of Food Science, Purdue University, 745 Agriculture Mall Dr., West Lafayette, IN, 47907, USA.
Food Safety Laboratory, Department of Food Science, Purdue University, 745 Agriculture Mall Dr., West Lafayette, IN, 47907, USA.
Probiotics Antimicrob Proteins. 2020 Dec;12(4):1571-1581. doi: 10.1007/s12602-020-09653-8.
Bioactive peptides derived from chia (Salvia hispanica) seed with antioxidant, antihypertensive, and anti-inflammatory activities have been well documented; however, few studies describe the antimicrobial properties of these peptides, which is of great interest not only in the prevention of food-borne diseases but also food spoilage. The aim of this study was to generate chia seed peptides using microwave-assisted hydrolysis with sequential (alcalase + flavourzyme) enzymes (AF-MW), fractionate them into 3-10 and < 3 kDa fractions, and evaluate their potential antimicrobial activity towards Escherichia coli, Salmonella enterica, and Listeria monocytogenes. Overall, the peptide fraction < 3 kDa showed higher antimicrobial activity than both chia seed hydrolysate and peptide fraction 3-10 kDa. Furthermore, the < 3 kDa fraction showed remarkable increase in membrane permeability of E. coli (71.49% crystal violet uptake) and L. monocytogenes (80.10% crystal violet uptake). These peptides caused a significant extension in the lag phase, decreases in the maximum growth, and growth rate in the bacteria and promoted multiple indentations (transmembrane tunnels), membrane wrinkling, and pronounced deformations in the integrity of the bacterial cell membranes. Finally, a select group of peptides in the AF-MW < 3 kDa fraction contained 16 sequences with cationic and hydrophobic character, with seven of them sharing the exact same sequence (GDVIAIR) and eight of them having the amino acid K as either N- or C-terminal or both. In conclusion, our results indicate that bioactive peptides obtained from chia seed proteins by microwave and enzymatic hydrolysis could be employed as antimicrobial agents in foods and therapeutic applications.
从奇亚（Salvia hispanica）种子中衍生出的具有抗氧化、降血压和抗炎活性的生物活性肽已有大量文献记载；然而，很少有研究描述这些肽的抗菌特性，这不仅在预防食源性疾病方面而且在防止食物变质方面都非常有趣。本研究旨在使用微波辅助水解与顺序（碱性蛋白酶+风味蛋白酶）酶（AF-MW）生成奇亚种子肽，将其分为 3-10 和 <3 kDa 级分，并评估它们对大肠杆菌、肠炎沙门氏菌和单核细胞增生李斯特菌的潜在抗菌活性。总体而言，<3 kDa 的肽级分显示出比奇亚种子水解产物和 3-10 kDa 肽级分更高的抗菌活性。此外，<3 kDa 级分对大肠杆菌（71.49%结晶紫摄取）和单核细胞增生李斯特菌（80.10%结晶紫摄取）的膜通透性有显著提高。这些肽导致大肠杆菌（71.49%结晶紫摄取）和单核细胞增生李斯特菌（80.10%结晶紫摄取）的滞后期显著延长，最大生长和生长速率降低，并促进了多个凹痕（跨膜隧道）、膜起皱和细菌细胞膜完整性的明显变形。最后，AF-MW <3 kDa 级分中的一组选定肽含有 16 个具有阳离子和疏水性特征的序列，其中 7 个具有相同的序列（GDVIAIR），8 个具有 K 作为 N-或 C-末端或两者。总之，我们的结果表明，通过微波和酶水解从奇亚种子蛋白获得的生物活性肽可用作食品和治疗应用中的抗菌剂。
