【摘要】 背景:五谷虫抗菌物质提纯方法存在争议,抗菌作用机制不清。目的:分离纯化五谷虫抗菌物质,并明确其抗菌机制。方法:应用超滤法对五谷虫粗提物进行纯化,用酶标浊度法及K-B纸片琼脂扩散法筛选出具有明显抗菌活性的滤出液;MTT法检测滤出液对金黄色葡萄球菌增殖的影响及测定最低抑菌浓度(MIC);应用电镜技术观察抗菌物质作用后金黄色葡萄球菌的形态变化。结果与结论:酶标浊度法及K-B纸片琼脂扩散法均显示与五谷虫粗提物及截留液相比较,滤出液(Mr<10000)的抗菌活性最强(P<0.05),能明显抑制金葡萄菌增殖,且对金黄色葡萄球菌的最低抑菌浓度(MIC)为1g/L。五谷虫滤出液抗菌物质能使金黄色葡萄球菌细胞膜的通透性增加,使细菌细胞膜破裂,细胞内容物渗出。五谷虫抗菌物质相对分子质量小于10000,其可能通过作用于金黄色葡萄球菌细胞膜而形成孔洞,增加细胞膜通透性,而发挥抗菌作用。更多还原

【Abstract】 BACKGROUND: The antibacterial substances purification from Wu Gu Chong is controversial, and the antibacterial mechanism is unclear. OBJECTIVE: To isolate and purify antibacterial substances from Wu Gu Chong and to identify its related antibacterial mechanism. METHODS: After ultra-filtration, the Turbidometric assay and Kirby-Bauer disk diffusion susceptibility test were used to examine the antibacterial activity of the fractions against Staphylococcus aureus. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to examine the effect of the extracts of maggot that was screened on the proliferation of Staphylococcus aureus and to determine the minimum inhibitory concentration. Electron microscopy was used to examine the ultra-structural changes ofStaphylococcus aureus induced by antimicrobial substances of the extracts. RESULTS AND CONCLUSION: The filtrate (M r < 10 000) had the best antibacterial activity against Staphylococcus aureus (P < 0.05), which significantly inhibited the proliferation of Staphylococcus aureus. The minimum inhibitory concentration was 1 g/L. The antibacterial substances of maggot increased the permeability and destroyed the cell membrane of Staphylococcus aureus. The anti-Staphylococcus aureus substances from Wu Gu Chong was less than 10 000, and its related mechanisms of anti-bacterial effect was a disruption of the outer and cytoplasmic membranes leading to lysis of the target cells.更多还原