植物乳杆菌KF1对奶牛乳房炎金黄色葡萄球菌的抑菌机制  

Antibacterial Mechanism of Lactobacillus plantarum KF1 on Staphylococcus aureus Isolated from Subclinical Mastitis Milk

作　　者：许女[1,2] 史改玲[2] 张浩[2] 杜立红[2] 王俊东[1] 

机构地区：[1]山西省生态畜牧与环境兽医学重点实验室山西农业大学,山西太谷030801 [2]山西农业大学食品科学与工程学院,山西太谷030801

出　　处：《中国食品学报》2016年第10期19-27,共9页Journal of Chinese Institute Of Food Science and Technology

基　　金："十二五"国家科技支撑计划项目(2012BAD12B06)

摘　　要：从开菲尔奶中筛选出一株具有强抑菌活性的乳酸菌KF1,经16S rDNA测序鉴定为植物乳杆菌。排除有机酸、过氧化氢的干扰试验,通过蛋白酶K和胰蛋白酶水解试验,证明该菌株产生的抑菌活性物质具有蛋白质性质,是一种细菌素。该细菌素在pH值2~4范围内抑菌效果稳定,当pH值达到8时,抑菌活性完全丧失;在121℃处理60 min后,仍保留约68%的活性,稳定性较好。抑菌谱试验表明,KF1细菌素对13株奶牛乳房炎病原菌都有不同程度的抑制作用,其中,对无乳链球菌、表皮葡萄球菌、溶血葡萄球菌等革兰氏阳性菌的抑菌作用最强,抑菌直径大于18 mm,抑制效果优于G―菌。通过研究KF1细菌素对菌体细胞壁、细胞膜通透性的影响,揭示其抑菌机制为膜孔道渗漏机制。另外,本文还发现KF1细菌素对多重耐药金黄色葡萄球菌生物被膜的形成―主要的毒力因子具有明显的抑制作用,显示其在奶牛乳房炎预防、治疗方面的应用前景。In this paper, the strain of KF1 with strong antimicrobial activity was screened from Chinese traditional kefir milk, and was identified as Lactobacillus plantarum by 16 S rDNA sequenced. After eliminating some interference factors such as organic acids, hydrogen peroxide, finally, the antibacterial substance in the culture supernatant was confirmed as proteinaceous―a kind of bacteriocin through the hydrolization test by proteinase K and trypsin. The bacteriocin showed high temperature stability up to 121 ℃ for 30 min with less loss in its activity, and had pH stability in the range of 2-4. When the pH value reaches 8, the antibacterial activity would have been completely lost. The results showed that KF1 bacteriocin had different degrees of antibacterial activity to 13 pathogens isolates from bovine mastitis cases. Compared to some gram-negative bacterias, gram-positive bacterias such as Streptococcus agalactiae, Staphylococcus epidermidis and Staphylococcus haemolyticus were more sensitive to the bacteriocin. The antibacterial mechanism was proved as membrane channel leakage through the determination of cell wall and cell membrane permeability parameters.Also, it was found that KF1 bacteriocin had obvious inhibitory effect on the biofilm formation（the main virulence factor）of antimicrobial resistant Staphylococcus aureus, and all of this proved its broad prospects in the prevention and treatment of dairy cow mastitis.

关 键 词：植物乳杆菌KF1 奶牛乳房炎 金黄色葡萄球菌 抑菌 

分 类 号：S858.23[农业科学—临床兽医学]