目的对一株小单孢菌属放线菌Micromonospora sp.(No.69)的抗耐甲氧西林金黄色葡萄球菌(MRSA)活性成分进行研究。方法采用活性追踪分离的方法,通过硅胶开放柱色谱、Sephadex LH 20柱色谱、ODS开放柱色谱、反相高效液相色谱等手段对Micromonospora sp.(No.69)发酵液的甲醇提取物进行分离和纯化,利用ESI-MS、~1H-NMR、~(13)C-NMR等波谱技术对单体化合物进行结构鉴定。结果从Micromonosporasp.(No.69)发酵液的甲醇提取物中分离得到8个化合物,分别鉴定为:环(L-缬-L-脯)二肽(1)、环(L-异亮-L-脯)二肽(2)、环(L-亮-L-脯)二肽(3)、环(甘-L-脯)二肽(4)、环(苏-L-脯)二肽(5)、环(L-丙-L-脯)二肽(6)、环(L-酪-L-脯)二肽(7)、环(L-苯丙-L-脯)二肽(8)。抗MRSA活性测试结果表明化合物1和2对MRSA具有抑制作用,IC_(50)分别为3.2 mmol·L~(-1)和6.5 mmol·L~(-1)。结论以上化合物均为首次从该属菌株中分离得到,其中化合物1和2显示出抗MRSA活性。 Objective To study the antimicrobial activity of MRSA against Micromonospora sp. (No.69). Methods The methanol extract of Micromonospora sp. (No.69) fermentation broth was separated by silica gel column chromatography, Sephadex LH 20 column chromatography, ODS open column chromatography and reverse phase high performance liquid chromatography (RP-HPLC) The structures of the compounds were identified by ESI-MS, ~ 1H-NMR and ~ (13) C-NMR. Results Eight compounds were isolated from the methanol extract of the fermentation broth of Micromonospora sp. (No.69) and identified as the dipeptide (1), (L-isole-L (2), cyclic dipeptide (3), cyclic dipeptide (4), cyclic (threo-L-) dipeptide Dipeptide (7), cyclic (L-phenylpropionamide) dipeptide (8) ). The results of anti-MRSA activity test showed that compounds 1 and 2 have inhibitory effect on MRSA with IC 50 of 3.2 mmol·L -1 and 6.5 mmol·L -1, respectively. Conclusion The above compounds were isolated from this genus for the first time, among which compounds 1 and 2 showed anti-MRSA activity.