香叶醇体外抗MRSA活性研究

目的 通过体外抑菌实验，评价香叶醇单独使用以及与3种β-内酰胺类抗生素(阿莫西林、头孢氨苄及头孢吡肟)联合使用对耐甲氧西林金黄色葡萄球菌(methicillin resistant Staphylococcus aureus, MRSA)的抑制效果。方法 采用微量稀释法测定香叶醇与3种β-内酰胺类抗生素的最低抑菌浓度(minimum inhibitory concentration, MIC)及最低杀菌浓度(minimum bactericidal concentration, MBC)；微量棋盘法测定香叶醇与3种β-内酰胺类抗生素的分级抑菌浓度指数(fractional inhibitory concentration, FIC)。结果与结论 香叶醇具有明显的体外抗MRSA活性，MIC和MBC分别为0.34~0.69mg/mL和0.69~10.76mg/mL。联合药敏试验发现香叶醇与3种β-内酰胺类抗生素联合使用FIC指数集中分布在≤0.5和0.5~1；能够增强β-内酰胺类抗生素的活性，降低其用量，使其MIC50和MIC90降低为单独用药的1/8~1/4和1/4~1/2。

In vitro antibacterial activity of geraniol against methicillin-resistant Staphylococcus aureus

Objective To explore the in vitro antibacterial activity of geraniol against methicillin-resistant Staphylococcus aureus (MRSA) and evaluate the inhibitory effect of geraniol combined with three β-lactam antibiotics against MRSA. Methods The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of geraniol were determined by 96-well plate dilution method. The microfluidic method was used to determine the fractional inhibitory concentration (FIC) index of three kinds of β-lactam antibiotics (amoxicillin, cefalexin and cefepime) combined with geraniol. Results and Conclusions Geraniol showed obvious in vitro anti-MRSA activity, MIC and MBC were 0.34~0.69mg/mL and 0.69~10.76mg/mL, respectively. Combined drug susceptibility test showed that FIC index of geraniol combined with three β-lactam antibiotics mainly distributed in 0.5~1 and 0.5; Compared to the β-lactam antibiotic alone group, geraniol enhanced β-lactam antibiotics activity, reduced the MIC50 and MIC90 of three antibiotics to 1/8~1/4 and 1/4~1/2, respectively. Geraniol exhibited obvious anti-MRSA activity and synergistic antibacterial activity with β-lactam antibiotics, which showed some potential applications effect on the development of natural anti-MRSA