山楂活性组分与β-内酰胺类抗生素的联合抑菌作用

Antibacterial activity of active component of Crataegus pinnatifida combined with β-Lactam antibiotics against methicillin-resistant Staphylococcus aureus in vitro

目的研究山楂提取物与β-内酰胺类抗生素对耐甲氧西林金黄色葡萄球菌(methicillin-resistant staphylococcus aureus,MRSA)的体外联合抗菌作用。方法干燥山楂去核切片75%乙醇提取,依次经乙酸乙酯、正丁醇萃取,取正丁醇层经D-101大孔树脂、硅胶柱色谱分离得到组分CP,体外药敏试验验证其联合4种β-内酰胺类抗生素(苯唑西林、舒氨西林、氨苄西林、头孢唑啉)抑制MRSA的作用。结果单独应用苯唑西林、舒氨西林、氨苄西林、头孢唑啉及组分CP对实验株MRSA的最低抑菌浓度(MIC)分别为256、512、512、128、1024μg/ml;联合用药时,亚MIC浓度的组分CP(128μg/ml)使苯唑西林、舒氨西林、氨苄西林、头孢唑啉MIC分别降低至2、32、16、2μg/ml,部分抑菌指数(FIC)分别为0.13、0.16、0.19、0.14,均小于0.5。结论山楂活性组分CP与β-内酰胺类抗生素具有显著的体外协同抑制MRSA的作用。

Objective To study the in vitro antibacterial activities of the Crataegus pinnatifida （C. p） extracts in combination with 4 kinds of β-lactams antibiotics against methicillin-resistant Staphylococcus aureus （MRSA）. Methods The dried fruits of C. p were extracted with 75% EtOH followed by being extracted successively with EtOAc and n-BuOH, then the obtained n-BuOH layer was subjected to macroporous D-101 and then to silica gel column chromatography. Finally we obtained the active component of C. p （CP）, and validate the in vitro antibacterial activities of the component CP in combination with 4 kinds of β-lactams antibiotics against MRSA. Results The minimal inhibitory concentration （MIC） of Oxacillin, Ampicillin sodiumsulbactam sodium, Ampicillin, Cephazolin and CP component were 256, 512, 512, 128 and 1 024 μg/ml, However, when combined with the C. p component at its sub-MlC （128 μg/ml） , the MIC of the above 4 kinds of β-lactams antibiotics was as lower as 2, 32, 16 and 2 μg/ml respectively. The fractional inhibitory concentration （FIC） of them were 0.13, 0.19, 0.16 and 0.14, respectively. Conclusion C. p component has synergistic antibacterial effect on MRSA when combined with β-lactams antibiotics.