小叶锦鸡儿花和根中黄酮及多酚类的抑菌活性

目的]分离小叶锦鸡儿花和根中不同极性的黄酮类和多酚类物质,并研究其体外抑菌活性。方法]将小叶锦鸡儿花和根经超声波辅助提取后进行液-液萃取分离,用琼脂扩散法测定粗提物和不同极性组分的体外抑菌效果,并研究其与黄酮类和多酚类含量的相关性。结果]小叶锦鸡儿花和根的不同极性组分对枯草芽孢杆菌和镰刀菌有抑制作用,但对金黄色葡萄球菌和大肠杆菌的抑制作用不明显。花的二氯甲烷层对枯草芽孢杆菌和镰刀菌的抑制活性最高,效价分别为176.78和243.97 IU/mg。相关性分析表明,黄酮类和多酚类是小叶锦鸡儿抑制枯草芽孢杆菌和镰刀菌的活性成分。结论]小叶锦鸡儿花和根中的黄酮类和多酚类物质在开发植物源抗菌食品添加剂、水果保鲜剂和抗菌药物方面具有应用价值和开发前景。

Preparation of Flavonoids and Polyphenols with Different Polarity from Caragana microphylla Lam.and Their Antimicrobial Activity

Objective] To prepare flavonoids and polyphenols with different polarity from roots and flowers of Caragana microphylla Lam.,and to test their antimicrobial activities in vitro.Method] Roots and flowers were subjected to crude extraction and liquid-liquid partitioning after ultrasound-assisted crude extraction.The antimicrobial activity of resultant extracts and fractions were determined,and the correlations between their antimicrobial activity and total flavonoid and total polyphenol contents were analyzed.Result] The fractions and crude extract showed inhibitory effect on Bacillus subtilis and Fusarium spp.,but did not showed substantial inhibitory effect against Staphylococcu saureus and Escheichia coli.Dichloromethane fraction of flower crude extract exhibited the highest inhibitory activity against B.subtilis and Fusarium spp.,with titers of 176.78 IU/mg and 243.97 IU/mg,respectively.Correlation analyses suggested that flavonoids and polyphenols were compounds responsible for inhibitory effect of C.microphylla on B.subtilis and Fusarium spp..Conclusion] Flavonoids and polyphenols from flowers and roots of C.microphylla may have various applications and great potential in development of plant-derived antimicrobial food additives,fresh fruit preservatives and medicines.