Wang Ruixue, Han Zhihao, Ji Rimutu, Xiao Yuchen, Si Rendalai, Guo Fucheng, He Jing, Hai Le, Ming Liang, Yi Li
Key Laboratory of Dairy Biotechnology and Bioengineering, Ministry of Education, College of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, Inner Mongolia, China.
Camel Research Institute of Inner Mongolia, Alxa 737300, Inner Mongolia, China.
Animals (Basel). 2020 Feb 20;10(2):337. doi: 10.3390/ani10020337.
Antibacterial peptides were isolated and purified from whey proteins of camel milk (CaW) and cow milk (CoW) and their antimicrobial activities were studied. The whey proteins were hydrolyzed using trypsin, and the degree of hydrolysis was identified by gel electrophoresis. The whey hydrolysate (WH) was purified using ultrafiltration and Dextran gel chromatography to obtain small peptides with antibacterial activity. The effect of the antimicrobial peptides on the morphology of bacterial strains was investigated using transmission electron microscopy. Their amino acid composition and antimicrobial activities were then determined. Polypeptides CaWH-III (<3 kDa) and CoWH-III (<3 kDa) had the strongest antibacterial activity. Both Fr.A2 (CaWH-Ⅲ's fraction 2) and Fr.B1 (CoWH-Ⅲ's fraction 1) had antibacterial effects toward and , with minimum antimicrobial mass concentrations of 65 mg/mL and 130 mg/mL for Fr.A2, and 130 mg/mL and 130 mg/mL for Fr.B1, respectively. The highly active antimicrobial peptides had high amounts of alkaline amino acids (28.13% in camel milk Fr.A2 and 25.07% in the cow milk Fr.B1) and hydrophobic amino acids. (51.29% in camel milk Fr.A2 and 57.69% in the cow milk Fr.B1). This results showed that hydrolysis of CaW and CoW using trypsin produced a variety of effective antimicrobial peptides against selected pathogens, and the antibacterial activity of camel milk whey was slightly higher than that of cow milk whey.
从骆驼奶（CaW）和牛奶（CoW）的乳清蛋白中分离纯化抗菌肽，并研究其抗菌活性。用胰蛋白酶水解乳清蛋白，通过凝胶电泳鉴定水解程度。利用超滤和葡聚糖凝胶色谱法纯化乳清水解物（WH），以获得具有抗菌活性的小肽。使用透射电子显微镜研究抗菌肽对细菌菌株形态的影响。然后测定它们的氨基酸组成和抗菌活性。多肽CaWH-III（<3 kDa）和CoWH-III（<3 kDa）具有最强的抗菌活性。Fr.A2（CaWH-Ⅲ的第2部分）和Fr.B1（CoWH-Ⅲ的第1部分）对[具体细菌1]和[具体细菌2]均有抗菌作用，Fr.A2的最低抗菌质量浓度分别为65 mg/mL和130 mg/mL，Fr.B1的最低抗菌质量浓度分别为130 mg/mL和130 mg/mL。高活性抗菌肽含有大量碱性氨基酸（骆驼奶Fr.A2中为28.13%，牛奶Fr.B1中为25.07%）和疏水氨基酸（骆驼奶Fr.A2中为51.29%，牛奶Fr.B1中为57.69%）。结果表明，用胰蛋白酶水解CaW和CoW可产生多种针对所选病原体的有效抗菌肽，且骆驼奶乳清的抗菌活性略高于牛奶乳清。
