摘要
以模式菌大肠杆菌为供试菌,研究淫羊藿生物碱的抑菌作用。采用二倍稀释法测定淫羊藿生物碱对大肠杆菌的最小抑菌浓度,采用牛津杯法测量抑菌圈直径。通过分析淫羊藿生物碱对大肠杆菌生长曲线、胞外和胞内可溶性蛋白量、胞外核酸量、金属离子量、菌体培养液电导率以及菌体超微结构的影响,探讨淫羊藿生物碱的抑菌机理。结果表明,淫羊藿生物碱对大肠杆菌具有较强的抑制作用,主要抑制大肠杆菌对数期的生长,最小抑菌浓度为60 mg/mL。淫羊藿生物碱处理后,大肠杆菌的胞外、胞内可溶性蛋白量显著增加,胞外K^+、Mg^(2+)离子和核酸相对量也显著升高,菌体培养液的电导率显著改变。扫描电子显微镜观察发现,淫羊藿生物碱能使大肠杆菌菌体之间相互粘连、聚团,菌体表面出现孔洞和凹陷,细胞表面严重破损。淫羊藿生物碱对大肠杆菌的抑制作用很可能与其对细胞结构的破坏有关。
The antibacterial activity of alkaloids from Epimedium was studied using Escherichia coli as a model microorganism.The minimum inhibitory concentration of Epimedium alkaloids against E.coli was determined by a broth dilution method.And the inhibition zone diameter was measured by an Oxford cup method.In order to identify antibacterial mechanism of Epimedium alkaloids,effects of alkaloids on soluble protein,nucleic acid, metallic ions,electrical conductivity and cell ultrastructure were investigated systematically.Epimedium alkaloids exhibited relatively high inhibitory activity against E.coli mainly during exponential growth phase,and the minimum inhibitory concentration of alkaloids was determined to be 60mg/mL.After E.coli was treated with Epimedium alkaloids,the contents of extracellular and intracellular soluble protein were found to increase remarkably.Relative contents of K＋,Mg（2＋）and nucleic acid outside cells of E.coli also increased significantly.And electrical conductivity of E.coli broth changed markedly.Some cavities and hollows took place on cell surface,whichindicated that cell surface was seriously destroyed.In summary,antibacterial activity of Epimedium alkaloids against E.coli was most probably related to destructive effects on cell structures.
出处
《陕西师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第6期74-79,共6页
Journal of Shaanxi Normal University：Natural Science Edition
基金
陕西省自然科学基础研究计划(2015JM3101)
陕西省科技合作计划项目(2014SJ-01)
中央高校基本科研业务费专项资金(GK201503002,2016CSZ008)
大学生创新创业训练计划(cx16124)
关键词
淫羊藿
生物碱
大肠杆菌
抑菌机理
Epimedium
alkaloid
Escherichia coli
antibacterial mechanism
