论文部分内容阅读
【目的】采用不同实验方法测定常用有机溶剂二甲基亚砜(DMSO)、丙酮和乙醇对细菌活性的影响,以指导抗菌类药物体外抑菌实验所用溶剂的选择和添加限量。【方法】采用常规体外抑菌实验方法(纸片扩散法、肉汤稀释法),并参照生长曲线法检测有机溶剂DMSO、丙酮和乙醇对大肠杆菌(Escherichia coli)及金黄色葡萄球菌(Staphylococcus aureus)的抑菌作用,采用扫描电子显微镜(SEM)观察溶剂作用后的细菌形态变化。【结果】3种溶剂对E.coli和S.aureus抑菌率达到20%时,在肉汤稀释法下,DMSO、丙酮、乙醇的浓度(体积比)分别为1.00%、0.25%、2.00%和1.00%、1.00%、0.50%;在生长曲线法下,溶剂浓度(体积比)分别为0.50%、1.00%、0.50%和1.00%、0.50%、0.50%;而在纸片扩散法下,32%(体积比)DMSO和32%(体积比)乙醇对E.coli产生明显抑菌圈,但3种溶剂对S.aureus均无抑菌圈出现。3种方法比较后得出:当3种溶剂的抑菌率达到20%时,溶剂浓度(体积比)均低于0.5%,对细菌整体生长活性影响较小。SEM结果表明控制溶剂使用限量可有效减少其对E.coli生长过程的影响。【结论】相对于DMSO和丙酮,乙醇对微生物生长繁殖能力的影响更加明显;采用相同浓度有机溶剂时,液态条件下(肉汤稀释法和生长曲线法)微生物受到有机溶剂的影响较大。
【Objective】 Different experimental methods were used to determine the effect of common organic solvents such as dimethyl sulfoxide (DMSO), acetone and ethanol on the activity of bacteria in order to guide the choice of antimicrobial agents for antibacterial experiments in vitro and the limits of addition. 【Method】 The antibacterial activity against Escherichia coli and Staphylococcus aureus was determined by routine antibacterial test in vitro (disk diffusion method and broth dilution method), and the growth curve method was used to detect the inhibitory effects of DMSO, acetone and ethanol on Escherichia coli and Staphylococcus aureus ) Antibacterial activity, the use of scanning electron microscopy (SEM) to observe the role of bacteria after bacterial morphological changes. 【Result】 The results showed that the concentrations of DMSO, acetone and ethanol were 1.00%, 0.25% and 2.00% when the antibacterial rate of E.coli and S. aureus reached 20% And 1.00%, 1.00% and 0.50% respectively. Under the growth curve method, the solvent concentration (volume ratio) was 0.50%, 1.00%, 0.50% and 1.00%, 0.50% and 0.50% 32% (volume ratio) of DMSO and 32% (volume ratio) of ethanol produced significant inhibition zone of E. coli, but no solvent inhibition of S. aureus appeared in all three solvents. The comparison of the three methods shows that when the antibacterial rate of the three solvents reaches 20%, the solvent concentration (volume ratio) is less than 0.5%, which has little effect on the overall growth activity of bacteria. SEM results show that the use of controlled solvent can effectively reduce the impact on the growth of E. coli. 【Conclusion】 The effect of ethanol on growth and reproduction of microorganisms is more obvious than that of DMSO and acetone. Under the same concentration of organic solvent, the microorganism under the influence of organic solvent is more affected by the broth dilution method and growth curve method.