Study On Chemical Components And Antioxidation In Leaves Of Ligularia Fischeri

Ligularia fischeri (Ledeb) Turcz. which belongs to compositae has been used widely for a long history in various regions of China. Its unique scientific value deserves to be explored. The topics in our paper mainly focused on chemical composition and its antioxidant activity of the entire plants which collected from Tumen city of Yanbian.Methanol extract and Petr.ether, CH2Cl2, n-BuOH and H2O fractions of Ligularia fischeri showed potential antioxidant activities against DPPH radical. They were investigated the antioxidant activities using the bioassay-linked fractionation method. MeOH extract and n-BuOH fraction from Ligularia fischeri appeared potent antioxidant effects against the DPPH radical, showing the IC50 values of 13.24 and 3.70μg/mL, respectively.With chloroform as solvent, the liposoluble constituents in Ligularia fischeri were extracted by ultrasonic extraction. The extracted substances were isolated and identified by GC-MS. The relative content of each constituent in liposoluble components was ascertained by peak area normalization of chromatogram.19 components were identified, which took up 71.58%of the total amount.By using different methods such as silica gel column, Sephadex LH-20 gel column chromatography as well as thin-layer, Ligularia fischeri were extracted and 6 compounds were isolated. Through the use of ESI-MS,'H-NMR,13C-NMR and 2D-NMR detection methods for structural identification, they were identified as hyperoside,2"-acetylhyperoside, 3-oxo-8α-methoxy-10αH-eremophila-1,7(11)-dien-12,8β-olide, liguhodgsonal,β-sitosterol and daucosterol, respectively. And hyperoside,2"-acetylhyperoside were isolated from Ligularia genus for the first time. 3-oxo-8α-methoxy-10αH-eremophila-1,7(11)-dien-12,8β-olide was isolated from Ligularia fischeri for the first time.The contents of hyperoside and 2"-acetylhyperoside in the Ligularia fischeri were determined to be 0.387 and 0.526 mg/g respectively with modern analysis measurement tools based on the 2005 edition of Chinese Pharmacopoeia combined. The results show that the method is sensitive, accurate, reproducible and reliable.Study on antioxidant activity of Ligularia fischeri was carried out through conventional antioxidant activity evaluation methods in vitro, such as determination of total antioxidant capacity, measured hydroxyl radical, DPPH radical scavenging experiment, etc. Ligularia fischeri on methaol extrcat, the fractions and the purified compounds were tested respectively. The results of three methods were consistent which show methaol extrcat, n-butanol and water fractions, and hyperoside and 2"-acetylhyperoside have strong antioxidant activity.It is a very important and practical task to carry out the research of traditional medicine Ligularia fischeri. On the one hand, we can make up for the shortage of the research of Ligularia fischeri in and abroad; on the other hand, we can promote the development and utilization of medicinal plant resources in minority areas.