蛙源抗菌肽Magainin Ⅱ对畜禽常见病原菌抑菌活性与体外稳定性测定  

Investigation of antibacterial activity and vitro stability of Magainin Ⅱ to common pathogenic bacteria in livestock and poultry

作　　者：徐欣欣 施平伟 张海文 Xu Xinxin;Shi Pingwei;Zhang Haiwen

机构地区：[1]海南大学热带农林学院,海南海口570228 [2]海南大学热带动物繁育与营养学实验室,海南海口570228

出　　处：《饲料工业》2018年第20期34-39,共6页Feed Industry

基　　金：海南省科协青年科技英才学术创新计划项目[QCXM201804]

摘　　要：抗菌肽MagaininⅡ是来源于非洲爪蟾体内的一种具有抗菌活性的小肽类物质。试验采用微量肉汤稀释法测定蛙源抗菌肽MagaininⅡ对几种常见畜禽致病菌的抑菌活性;在此基础上将抗菌肽MagaininⅡ在不同温度、pH值及人工胃蛋白酶与胰蛋白酶进行处理,进而评价其稳定性。试验结果表明,抗菌肽MagaininⅡ对革兰氏阳性菌不具有抑菌作用,但对几种革兰氏阴性菌表现出一定的抗菌活性,MIC值处于64~256μg/ml;由时间杀菌曲线可知,MagaininⅡ不能有效抑制金黄色葡萄球菌ATCC 25923菌落的形成,但能够在90 min内对大肠杆菌ATCC 25922发挥抑制作用;MagaininⅡ的稳定性测试结果表明,分别经不同温度、pH值以及人工胃蛋白酶与胰蛋白酶处理后的MagaininⅡ对金黄色葡萄球菌ATCC 29523和表皮葡萄球菌ATCC 12228始终没有发挥抑菌活性,在经50~70℃处理后能够对大肠杆菌K12和肠炎沙门氏菌CMCC 50041稳定发挥抗菌效果,MIC值始终为64μg/ml;经两种人工酶处理后的MagaininⅡ对两种试验革兰氏阴性菌不再具有抑菌作用;经pH值为2处理后,MagaininⅡ对大肠杆菌K12和肠炎沙门氏菌CMCC 50041的MIC均为256μg/ml,比未处理时明显增大,经pH值为8处理后,MagaininⅡ不能抑制大肠杆菌K12,对肠炎沙门氏菌CMCC50041的MIC为128μg/ml。基于试验结果可推断:MagaininⅡ对革兰氏阳性菌抗菌效果不明显,对革兰氏阴性菌具有一定的抗菌效果,经人工酶处理后性质不稳定,该研究为MagaininⅡ在畜禽生产上的应用提供参考。Antibacterial peptide （Antimicrobial Peptides, AMPs） Magainin Ⅱ, a kind of small peptides which derives from Xenopus laevis, and has antibacterial activity. Nowadays, with the increasingly serious situation of antibiotic abuse, antimicrobial peptides have attracted more and more attention because of their broad-spectrum antimicrobial activity and they are not easy to produce bacterial resistance. In this study, micro-broth dilution method was used to investigate the antibacterial activity of Magainin Ⅱ against several common pathogenic bacteria of livestock and poultry. On this basis, anti-microbial peptides Magainin Ⅱ were processed at different temperatures, pH and artificial pepsin and trypsin, and then the stability of Magain- in Ⅱ was evaluated. The results showed that antibacterial peptide Magainin Ⅱ had no antibacterial effect on Gram-positive bacteria, but showed certain antibacterial activity to several Gramnegative bacteria, and the value of MIC was 64-256 μg/ml. According to the time-kill curve, Magain- in Ⅱ could not effectively inhibit the formation of Staphylococcus aureus ATCC 25923 colony, but could inhibit Escherichia eoli ATCC 25922 in 90 minutes. The stability test results of Magainin 11 showed that Magainin Ⅱ had no antibacterial activity on Staphylococcus aureus ATCC 29523 and Staphylococcus epidermidis ATCC 12228 after treatment at different temperatures, pH, and artificial pepsin and trypsin. It can maintain stable antibacterial effect on Escherichia coli K 12 and Salmonella enteritidis CMCC 50041 after treatment at 50-70℃, the MIC was always 64 μg/ml. Magainin Ⅱ treated by trypsin and pepsin was no longer antibacterial to two Gram-negative bacteria. After pH=2 treatment, the MIC of Magainin Ⅱ against Escherichia eoli K12 and Salmonella enteritis CMCC 50041 was 256 μg/ml, which was significantly higher than the MIC of untreated Magainin Ⅱ, after pH=8 treatment, Magainin Ⅱ did not inhibit Escherichia coli K12, and MIC of Salmonella enteritis CMCC 50041 was 128

关 键 词：MAGAININ Ⅱ 抑菌活性 稳定性 畜禽 病原菌 

分 类 号：S816.7[农业科学—饲料科学]