广西藤茶总黄酮与β-内酰胺类抗菌药物合用的体外抗菌活性研究

In Vitro Antibiotic Activities of Total Flavonoids from Guangxi Ampelopsis Grossedentata in Combination with β-lactam Antibiotics

目的研究广西藤茶总黄酮(TF)单用及与β-内酰胺类抗菌药物联用对金黄色葡萄球菌(SA)、耐甲氧西林金黄色葡萄球菌(MRSA)、肺炎克雷白杆菌、乙型副伤寒杆菌等临床常见细菌的抗菌活性。方法采用微量稀释法及棋盘法,分别测定TF对SA、MRSA、肺炎克雷白杆菌等临床常见细菌的最低抑菌浓度(MIC)及最低杀菌浓度(MBC)、TF与β-内酰胺类抗菌药物对SA和MRSA的联合抗菌指数(FIC)及生长曲线。结果单用TF对SA、MRSA的MIC均为77.50～155.00μg.mL-1;TF与β-内酰胺类抗菌药物合用,除与头孢唑林、头孢吡肟的0.5<部分抑菌浓度指数(FICI)≤1.0,为相加作用外,与苯唑西林、亚胺培南西司他丁钠、头孢西丁的FICI均≤0.5,表现为协同作用。结论 TF与β-内酰胺类抗菌药物合用对MRSA具有较强的体外抗菌活性。

Objective To investigate the activity of total flavonoids （TF） of Guangxi Ampelopsis grossedentata alone and in combination with β-lactam antibiotics against clinically important bacteria, including Staphylococcus aureus （SA）, Methi- cilli-resistant Staphylococcus aureus （MRSA）, Klebsiella pneumoniae and Beta paratyphoid bacilli. Methods The minimum inhibitory concentration （MIC） and minimum bactericidal concentration （MBC） of TF on these bacteria were tested by microdilu- tion. Fractional inhibitory concentration index （FICI） and growth curve of TF combined with β-lactam antibiotics against SA and MRSA were measured by checkerboard method. Results The MIC of TF alone on SA and MRSA was 77. 50- 155.00 μg. mL-1. The combination of TF and β-lactam antibiotics such as oxacillin, tienam, cefoxitin showed synergistic effects with FICI less than 0.5. However, the additive effect of the combination was absent from cefazolin or cefepime, where the FICI ranged from 0.5 to 1.0. Conclusion TF in combination with β-lactam antibiotics presents strong antibacterial effect a- gainst MRSA in vitro.