金莲花黄酮类成分抗菌及抗氧化活性研究

Study on antibacterial and antioxidant activities of flavonoids from Trollius chinensis Bge

目的比较研究金莲花总黄酮及其黄酮主成分荭草苷和牡荆苷的体外抗菌活性及抗氧化活性。方法体外抗菌活性试验采用管碟法对9个菌株(大肠杆菌、沙门氏菌、金黄色葡萄球菌、枯草芽孢杆菌、变异链球菌、链霉菌、红酵母、黑曲霉、白色念珠菌)进行体外抑菌圈测定;采用连续稀释法和活菌计数法测定最低抑菌浓度(MIC)和最低杀菌浓度(MBC);分别采用邻苯三酚法-超氧阴离子清除能力测定试验、水杨酸法-羟基自由基清除能力测定试验和DPPH清除能力试验评价3种样品的抗氧化活性差异。结果在体外抗菌活性试验中,金莲花总黄酮、荭草苷、牡荆苷对革兰阳性菌的抑菌效果明显,对革兰阴性菌和真菌无明显抑菌作用;3种药物对金黄色葡萄球菌表现出较好的抑菌活性,其抑菌作用强弱为荭草苷=总黄酮>牡荆苷,其中荭草苷和总黄酮的最低抑菌浓度和最低杀菌浓度分别为0.15625 mg·mL^(-1)和0.625 mg·mL^(-1);3种药物对变异链球菌也表现出较好的抑菌活性,其抑菌作用强弱为荭草苷>总黄酮>牡荆苷,其中荭草苷的最低抑菌浓度和最低杀菌浓度分别为0.15625 mg·mL^(-1)和0.625 mg·mL^(-1)。在抗氧化活性测定中,金莲花总黄酮对3种自由基均表现出较强的清除能力。结论金莲花总黄酮、荭草苷和牡荆苷对革兰阳性菌表现出明显的抑制作用,也表现出较好的抗氧化活性。荭草苷的杀菌效力及抗氧化活性整体上优于牡荆苷,可能是其清热解毒的主要成分。

Objective To compare the antibacterial and antioxidant activities of total flavonoids of Trollius chinensis and its main components orientoside and vitexin in vitro.Methods For in vitro antibacterial activity test,in vitro inhibition zone determination of nine strains(Escherichia coli,Salmonella,Staphylococcus aureus,Bacillus subtilis,Streptococcus mutans,Streptomyces,Rhodotorula,Aspergillus niger,Candida albicans)was carried out by the tube dish method;Minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)were determined by serial dilution and viable count methods;The difference in antioxidant activities of the three samples was evaluated by pyrogallol method superoxide anion scavenging capacity test,salicylic acid method hydroxyl radical scavenging capacity test and DPPH scavenging capacity test.Results In the in vitro antibacterial activity test,the total flavonoids of Trollius chinensis,orientoside and vitexin had obvious antibacterial effect on Gram-positive bacteria,but no obvious antibacterial effect on Gram-negative bacteria and fungi;For Staphylococcus aureus,the antibacterial ability of orientin and total flavonoids was stronger than that of vitexin.The MIC and MBC of orientin and total flavonoids were 0.15625 mg·mL^(-1)and 0.625 mg·mL^(-1),respectively;For Streptococcus mutans,the antibacterial ability of orientin was stronger than that of total flavone and vitexin.The MIC and MBC of orientin were 0.15625mg·mL^(-1)and 0.625 mg·mL^(-1),respectively.In the determination of antioxidant activity,the total flavonoids of Trollius chinensis showed a strong scavenging ability to three kinds of free radicals.Conclusion The total flavones of Trollius chinensis,orientoside and vitexin showed obvious inhibitory effects on Gram-positive bacteria,and also showed good antioxidant activity.The bactericidal efficacy and antioxidant activity of orientin,which may be the main component of its heat clearing and detoxification,were generally better than vitexin.