青蒿琥酯对耐甲氧西林金黄色葡萄球菌体外抗菌活性研究

In vitro antimicrobial activity of artesunate to Methicillin-resistant Staphylococcus aureus

目的探讨青蒿琥酯对耐甲氧西林金黄色葡萄球菌(Methicillin-resistant Staphylococcus aureus,MRSA)的体外抗菌活性。方法 MRSA标准菌株(标准组)和临床MRSA菌株20株(临床组),2组菌株培养皿中分别加入1 600、800、400、0mg/L青蒿琥酯溶液50μL,采用琼脂扩散法检测抑菌圈直径,采用液基稀释法检测青蒿琥酯的最低抑菌浓度(minimum inhibitory concentration,MIC)。观察2组青蒿琥酯联合头孢西丁、万古霉素、利奈唑胺、替考拉宁抗菌药物的MIC结果。结果标准组1 600、800mg/L青蒿琥酯溶液的抑菌圈直径[(20.4±2.4)、(18.6±1.1)mm]均大于临床组[(18.5±0.9)、(17.4±0.9)mm](P<0.05);青蒿琥酯单独使用时对MRSA的MIC>6 000mg/L,对MRSA几乎无抗菌作用;标准组和临床组800mg/L青蒿琥酯联合头孢西丁对MRSA的MIC分别为20、28mg/L,1 600mg/L青蒿琥酯联合头孢西丁对MRSA的MIC分别为16、22mg/L,均明显低于头孢西丁单独使用时(32、32mg/L)(P<0.05);2组青蒿琥酯联合万古霉素、利奈唑胺、替考拉宁对MRSA的MIC与单独使用青蒿琥酯时差异无统计学意义(P>0.05)。结论青蒿琥酯为一种对MRSA无明显抗菌活性,不可单独用于治疗由MRSA感染引起的多种疾病。

Objective To study in vitro antimicrobial activity of artesunate to Methieillin-resistant Staphylococcus aureus （MRSA）. Methods The petri dishes of standard MRSA strain （standard group） and 20 clinical MRSA strains （clinical group） were added 1600, 800, 400 and 0 mg/L artesunate solution 50μL. The agar diffusion method was used to detect the diameter of inhibition zone. The minimum inhibitory concentration （MIC） of artesunate was detected by liquid-based dilution method. The MICs of artesunate combined with antibiotics antimicrobial agents as cefoxitin, vancomycin, linezolid or teieoplanin were compared between two groups. Results The diameters of inhibition zone in 1 600 and 800 mg/L artesunate solution were longer in standard group （（20.4±2. 4）, （18. 6±1. 1） mm） than those in control group （（18.5±0.9）, （17. 4±0. 9） mm） （P〈0.05）. MIC of single use of 〉6 000 mg/L artesunnate showed no antibacterial activity to MRSA. MICs of 800 mg/L （20, 28 mg/L）, 1 600 mg/L （16, 22 mg/L） artesunate combined with cefoxitin were lower in standard group and control group than those of single use of cefoxitin （32, 32 mg/L）. MICs of combined use of artesunate with vancomycin, linezolid or teicoplanin showed no significant differences from that of single use of artesunate. Conclusion Since artesunate has no obvious antimicrobial activity, it could not be used individually to treat various diseases caused by MRSA infection.