摘要
为探究沙棘叶醇提物对鸡源大肠杆菌(Escherichia coli)的抑菌活性及其抑菌机制和抑菌稳定性,通过选择10种常见的抗生素对5株鸡源大肠杆菌菌株进行菌株药敏试验,确定其耐药特性;使用75%乙醇浸提沙棘叶干粉得到醇提物,设置1.00、1.50、2.00 g/mL、阳性对照(多黏菌素B)、空白对照(无菌生理盐水)5个组别,采用牛津杯法测定沙棘叶醇提物对筛出的5株鸡源大肠杆菌分离株的抑菌圈;微量肉汤稀释法测定最低抑菌浓度(MIC);微量酶标法检测菌液上清中核酸、蛋白质、碱性磷酸酶(AKP)和细菌中乳酸脱氢酶的含量(LDH);考马斯亮蓝染色检测细菌中可溶性蛋白质含量变化;扫描电子显微镜(SEM)观察菌体形态变化。结果表明,5株菌株对林可霉素、四环素、万古霉素耐药,对阿莫西林、大观霉素、氨苄西林、红霉素、链霉素部分耐药,而对庆大霉素、多黏菌素B全部敏感。1.00、1.50、2.00 g/mL沙棘叶醇提取物对鸡源大肠杆菌的抑菌圈直径分别为(11.23±0.44)mm、(12.77±0.53) mm、(13.59±0.52) mm;沙棘叶醇提物对鸡源大肠杆菌的MIC为125.00 mg/mL。与空白对照相比,沙棘叶醇提物处理后大肠杆菌菌液上清液中核酸、蛋白质和AKP含量显著上升(P<0.05),菌体细胞中LDH和可溶性蛋白质含量显著减少(P<0.05),菌体表面呈现凹陷、皱缩和破裂。综上,沙棘叶醇提物对鸡源大肠杆菌具有良好的体外抑菌活性,其潜在机制是通过破坏细胞壁完整性、改变菌种形态结构及抑制细菌内LDH活性和可溶性蛋白合成而发挥作用。
In order to explore the antibacterial activity,antibacterial mechanism and antibacterial stability of the ethanol extract of sea buckthorn leaves on chicken-originated Escherichia coli,the drug sensitivity test of 5strains of E.coli from chicken was carried out by selecting 10 common antibiotics to determine their drug resistance characteristics.The ethanol extract was obtained by extracting the dry powder of sea buckthorn leaves with 75%ethanol.Five groups were set up:1.00,1.50,2.00 g/mL,positive control(polymyxin B)and blank control(sterile normal saline).The Oxford cup method was used to determine the inhibition zone of the ethanol extract of sea buckthorn leaves on the five isolated strains of E.coli from chickens.The minimum inhibitory concentration(MIC)was determined by broth microdilution method.The contents of nucleic acid,protein,alkaline phosphatase(AKP)and lactate dehydrogenase(LDH)in the supernatant of bacterial liquid were detected by micro-enzyme labeling method.Coomassie brilliant blue staining was used to detect the change of soluble protein content in bacteria.The morphological changes of the bacteria were observed by scanning electron microscopy(SEM).The results showed that the five strains were resistant to lincomycin,tetracycline and vancomycin,par tially resistant to amoxicillin,spectinomycin,ampicillin,erythromycin and streptomycin,and all sensitive to gentamicin and polymyxin B.The inhibition zone diameters of 1.00,1.50,2.00 g/mL ethanol extract of sea buckthorn leaves on chicken Escherichia coli were(11.23±0.44)mm,(12.77±0.53)mm and(13.59±0.52)mm,respectively.The MIC of ethanol extract of seabuckthorn leaves against chicken E.coli was 125.00 mg/mL.Compared with the blank control,the contents of nucleic acid,protein and AKP in the supernatant of E.coli bacterial liquid increased significantly(P<0.O5),the contents of LDH and soluble protein in the bacterial cells decreased significantly(P<0.O5),and the surface of the bacteria showed depression,shrinkage and rupture.In summary,the ethanol extract of seabuckthorn leaves has good in vitro antibacterial activity against chicken-derived E.coli,and its potential mechanism is to destroy the integrity of cell wall,change the morphological structure of bacteria,and inhibit LDH activity and soluble protein synthesis in bacteria.
作者
王利敏
马玉龙
何莹
朱琳
辛子惠
赵航
卫丁一
刘连荣
戴小华
韩俊成
WANG Li-min;MA Yu-long;HE Ying;ZHU Lin;XIN Zi-hui;ZHAO Hang;WEI Ding-yi;LIU Lian-rong;DAI Xiao-hua;HAN Jun-cheng(College of Veterinary Medicine,Xinjiang Agricultural University,Urumqi 830052,China;Xinjiang Key Laboratory of New Drug Research and Development for Herbivorous,Urumqi 830052,China;Xinjiang Huachuang Agriculture and Forestry Ecological Technology Co.,Ltd,Hami 839000,China)
出处
《新疆农业大学学报》
2025年第4期296-303,共8页
Journal of Xinjiang Agricultural University
基金
新疆维吾尔自治区“三区”人才支持计划科技人员专项计划项目(2025年度)
哈密市科学研究与技术开发计划项目(HM-2024-kj017)
国家级大学生创业训练计划项目(202410758002X)
国家级大学生创新训练计划项目(20241075801)。
关键词
沙棘叶
提取物
鸡源大肠杆菌
体外抑菌
抑菌机制
sea buckthorn leaves
extracts
chicken-derived Escherichia coli
in vitro antibacterial activity
antibacterial mechanism
