三丫苦茎总提取物及分段样品抗菌活性研究

Antibacterial Properties of Total Extract and Ethanol Segments from Stem of Evodia lepta(Spreng. )Merr. against Common Pathogenic Bacteria in Vivo and in Vitro

目的考查三丫苦茎提取物体内外抗菌活性。方法体外实验采用肉汤连续二倍微孔稀释法测定三丫苦茎总提取物(SYK)对常见致病菌如金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌、肺炎克雷伯菌、粪肠球菌最小抑菌浓度(MIC);体内,采用对三丫苦茎总提取物敏感细菌尾静脉注射小鼠(亚致死剂量),复制细菌性脓毒症模型,考查三丫苦茎总提取物(SYK)及分段样品对细菌感染小鼠保护作用。结果在所检测细菌中,SYK对两株金黄色葡萄球菌ATCC29213、ATCC43300的MIC值均为12.5mg/m L(折算为206.3mg生药/m L),对其他细菌未检测出MIC值;与模型组比较,提前给予SYK(2g/kg,折算为33.0g生药/kg)明显增加脓毒症小鼠168h生存率,差异具有统计学差异(P<0.01);与模型组比较,SYK 20%、90%两个醇洗脱部位SYK20、SYK90明显提高脓毒症小鼠动物生存率(33.3%vs 16.7%,P<0.05;50%vs 16.7%,P<0.01)。SYK90对脓毒症小鼠保护率最高,但与SYK比较,其动物保护率稍有降低。结论体外,SYK对金黄色葡萄球菌具有明显抑制作用;体内,SYK及其分段样品SYK20、90对金黄色葡萄球菌感染小鼠具有明显保护作用。

Objective Antibacterial properties of total extract and ethanol segments from stem of Evodia lepta （Spreng. ） Merr. in vivo and in vitro. Methods In vitro, minimum inhibitory concentration （MIC） was determined by using the serial 2-fold broth dilution methods. In vivo, a sepsis mouse model challenged with sublethal Staphylococcus aureus was established to evaluate the anti-infective effect of there samples. Results Except the MICs of the total exact for two Staphylococcus aureus strains ATCC29213, ATCC43300 were both 12.5 mg/ml（206.3 mg crude drug/ml）, the total exact had no significant inhibition on other pathogenic bacteria such as Escherichia coli, Pseudomonas aeruginosa, Klebsiel a pneumoniae, and Enterococcus faecalis. In vivo, compared with the model group, the total extract of Evodia lepta（Spreng. ） Merr. significantly increased survival rate of the septic mice within 168 hours（P〈0.01）. The survival rates were markedly higher in the segments （SYK20, 90）-treated groups than that in the model group （P〈0.05; P〈0.01）. The survival rate was highest in the SYK90, but it was slightly lower than the total exact. Conclusion Taken together, in vitro, the total exact from Evodia lepta （Spreng. ） Merr. significantly inhibits the growth of Staphylococcus aureus. In vivo, the total exact total extract and ethanol segments（SYK20, 90） significantly protects the sepsis mice challenged with sublethal Staphylococcus aureus.