Preliminary Study On The Antimicrobial Activity Of Extracts From Ligularia

In this paper, the ground part of ligularia virgaurea as raw materials, is divided into flowers and leaf parts. Six different extracts were obtained after ultrasonic extraction by Anhydrous ethanol, chloroform, ethyl acetate. The antibacterial activity of Ligularia virgaurea extracts were tested with Escherichia coli, Salmonella and Staphylococcus aureus.The results were as follows:1. The extraction rate of different solvents were obviously different. The extraction yield of anhydrous ethanol at 2.16% which were better than acetic ether and chloroform.Cauline leaf contains active substances were significantly higher than flowers.antibacterial activity of Ligularia virgaurea extracts was assayed by oxford cup method. The results showed that bacteriostasis effect of anhydrous ethanol extract cauline leaf part of Ligularia virgaurea were the best. The Antimicrobial bacteriostatic circle diameter of Escherichia coli, Salmonella and Staphylococcus aureus were 13.8 mm,18.1 mm and 13.1 mm, respectively.2. The minimal bacterialcidal concentration(MIC) and minimum bactericidal concentration(MBC) was calculated using tube dilution method. The results showed that the MIC of anhydrous ethanol extracts to Escherichia coli, Salmonella and Staphylococcus was 50mg/mL、50mg/L、25mg/mL and the MBC was 50mg/mL、 100mg/mL、50mg/mL, respectively.3. The condition of low temperature and acid had little effection to antibacterial activity for extracts. In more than 60℃ and alkaline environment antibacterial activity decreased significantly and ultraviolet light had no effect on its antibacterial activity.4. The results of qualitative analysis showed that anhydrous ethanol extracts of cauline leaf contain phenols, alkaloids, organic acids and volatile oil. A total of seven components were isolated by column chromatography on silica gel. Three of the seven components had good antibacterial activity to staphylococcus aureus, and the antibacterial activity of material chemical composition were mainly phenolic and alkaloids. But the exact active substance need farther isolation, purification and identification.Conclusion:The chemical composition of ligularia virgaurea was very rich. Antimicrobial active substances been extracted effectively by anhydrous ethanol ultrasonic assisted extraction. The antibacterial substance had good antibacterial effect to common bacteria, which can be used as the development of new antibiotics and detergent raw materials.