7种中药提取物体外抑制金黄色葡萄球菌的效果及机制研究

The effect and mechanism of seven traditional Chinese medicine extracts on in vitro inhibition of Staphylococcus aureus

本研究旨在探究黄芩苷、小檗碱、杜鹃花、虎儿草、唐古特青蓝、诃子、沙棘果7种中药对金黄色葡萄球菌的体外抑菌效果以及其作用机制。通过微量肉汤稀释法测定7种不同中药材水或醇提取物对金黄色葡萄球菌的最小抑菌浓度,并测定不同药物提取物浓度下金黄色葡萄球菌的生长曲线,研究中药对金黄色葡萄球菌的体外抑菌效果;然后测定中药材对金黄色葡萄球菌生物被膜生成的影响、生物被膜通透性的影响和胞内三磷酸腺苷(ATP)含量的影响来研究其抑菌机制。结果表明,所有中草药提取物对金黄色葡萄球菌均有抑制作用,其中小檗碱和黄芩苷2种中药抑菌作用优于其他中药提取物。中药处理组的金黄色葡萄球菌生长缓慢,小檗碱对金黄色葡萄球菌的生长抑制作用最强。小檗碱、黄芩苷、唐古特青蓝、杜鹃花、沙棘果、虎儿草水提取物以及唐古特青蓝、杜鹃花、诃子、沙棘果、虎儿草的醇提取物能明显抑制金黄色葡萄球菌生物膜的形成。经过黄芩苷和小檗碱处理后,金黄色葡萄球菌胞外总蛋白和核酸含量与药物提取物浓度呈正相关增加。经过小檗碱作用后的金黄色葡萄球菌胞内的ATP含量显著下降。综上,7种中药对金黄色葡萄球菌有体外抑菌效果,能够抑制细菌的生长,其机制与影响金黄色葡萄球菌的生物被膜通透性以及细胞能量代谢相关。

The aim of this study was to investigate the in vitro antibacterial effects of seven Chinese herbal medicines,namely,baicalin,berberine,Rhododendron,Saxifraga stolonifera Meerb,Dracocephalum tanguticum Maxin,Terminalia chebula Retz.,and Hippophae rham⁃noides on Staphylococcus aureus and to explore their potential antibacterial mechanisms.The minimum inhibitory concentrations of the different herbal medicines against Staphylococcus aureus were determined using the micro-broth dilution method,and the in vitro inhibitory effects of these herbal medicines on Staphylococcus aureus were studied by measuring the growth curves of Staphylococcus aureus.Then,the effect of the herbal medicines on the biofilm production,biofilm permeability and intracellular adenosine triphosphate(ATP)content of Staphylococcus aureus were determined to reveal the potential antibacterial mechanisms.The results showed that all the herbal extracts had in⁃hibitory effects on Staphylococcus aureus,among which berberine and baicalin presented better inhibitory effects than other herbal extracts.The growth of Staphylococcus aureus in the herbal treatment group was slow,and berberine exhibited the strongest growth inhibition effect.The aqueous extracts of berberine,baicalin,Tangut Cyanine Blue,Azadirachta indica,Sea-buckthorn fruit,and Tiger grass,and the alco⁃holic extracts of Tangut Cyanine Blue,Azadirachta indica,Chebul,Sea-buckthorn fruit,and Tiger grass,significantly inhibited the formation of Staphylococcus aureus biofilm.After treatment with baicalin and berberine,the total extracellular protein and nucleic acid con⁃tents of Staphylococcus aureus increased in positive correlation with the concentration of drug extracts.The intracellular ATP content of Staph⁃ylococcus aureus treated with berberine decreased significantly.Taken together,the seven herbal medicines had in vitro antibacterial effects on Staphylococcus aureus and were able to inhibit bacterial growth by the mechanisms of affecting biofilm permeability and cellular energy metab⁃olism of Staphylococcus aureus.