36种中药材体外抗菌活性筛选研究

该文研究36种常用中药材80%乙醇提取物在体外抗临床常见致病菌的抗菌活性。采用药敏纸片法测耐药菌的耐药谱,中药粗粉用80%乙醇浸泡提取,提取液减压浓缩得浸膏,通过琼脂打孔法测定提取物抑菌圈,再通过微量倍比稀释法测定最低抑菌浓度(MIC)和最低杀菌浓度(MBC)。结果表明:36种中药材醇提物中,有15种具有广谱抗菌活性,对实验中各标准菌表现出不同程度的抑制作用,对MRSA抗菌活性也较强。其中,岩陀、卷柏、首乌藤、苏木、乌药、夏枯草6种药材的抗菌活性比较突出,抑菌圈均大于11 mm,细菌对其表现为中高度敏感;它们对7株标准菌的MIC/MBC值除个别为12.5 mg·m L~(-1)以外,均小于1.563 mg·m L~(-1),对16株MRSA的MIC/MBC值均小于1.563 mg·m L~(-1),它们的萃取层活性均小于1 mg·m L~(-1)。所筛选出的15种抗菌活性较强的中药材,可为后续研究其活性单体化合物和作用机制,研发有效的抗多重耐药菌的中药制剂以及解决细菌耐药性问题提供一定的参考。

Screening of antimicrobial activities of 36 Chinese herbal medicines in vitro

To determine the in vitro antimicrobial activities of 80% ethanol extracts from 36 common Chinese herbal medicines against common clinical pathogenic bacteria. The spectrum of multidrug-resistant clinical stains isolated from the sputum samples was determined by the Kirby-Bauer(K-B)method. The dried powder of the collected 36 Chinese herbal medicine samples were extracted with 80% ethanol and the solvent was evaporated under reduced pressure to get the ethanol extracts. The antimicrobial activities of each extract against bacteria or fungi were studied by screening inhibition zone diameters(IZDs)with agar-diffusion methods, and minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)were determined by serial microdilution method. The results showed that ethanol extracts of fifteen species among 36 species selected had wide spectrum of antimicrobial activities, including the activity against MRSA. Six kinds of Chinese herbal medicines had obvions antibacterial activities, i.e. Bergenia purpurascens, Selaginella tamariscina, Polygonum multiflorum, Caesalpinia sappan, Lindera aggregata and Prunella vulgaris. Their IZDs were greater than 11 mm and the bacteria showed moderately and highly sensitivity. The MIC/MBCs against seven standard strains were mostly less than 1.563 mg·mL^-1, in addition to 12.5 mg·mL^-1 individually. The MIC/MBCs against sixteen strains of MRSA were also less than 1.563 mg·mL^-1, and their sub-extracts were less than 1 mg·mL^-1. The fifteen species screened out among commonly used Chinese herbal medicines with good antibacterial activities could provide a basis for the subsequent activity tracking of isolated components, for the study on antibacterial mechanism and exploring effective Chinese medicine preparations against multiple resistant bacteria, and for solving the problem of bacterial resistance.