The Anti-inflammatory Activity and Chemical Composition Identification of Different Extracted Parts of Polygonum multifllorum Leaves
Objective:To study the chemical constituents of Polygonum multiflorum leaves and lay a foundation for the research and development of functional food of P.multiflorum.Methods:Organic solvent fractions was performed on the alcohol extract of P.multiflorum leaves to obtain different fractions parts such as petroleum ether,dichloromethane,ethyl acetate,n-butanol,and water.Anti-inflammatory activities were carried out on different extraction parts.The fractions with strong anti-inflammatory activity were separated and purified by using silica gel and C18 column combined with semipreparative HPLC methods.Results:The ethyl acetate fraction had no cytotoxicity on RAW264.7 cells in the con-centration range of 0-100 μg/mL and showed dose-dependent inhibition of NO production.Petroleum ether and dichloromethane fractions displayed no cytotoxicity in the concentration range of 0-25 μg/mL,the inhibitory rate on NO of dichloromethane fraction(51.47%)was higher than the fraction of petroleum ether(43.91%).Eleven compounds were isolated from the fractions of ethyl acetate and dichloromethane.The chemical structures were identified as 2,3,4,6-te-trahy-droxyacetophenone-3-O-β-D-glucoside(1),myricitrin(2),quercitrin(3),afzelin(4),β-sitosterol(5),n-hex-acos-5,8,11-trienoic acid(6),hexacosane(7),α-linolenic acid(8),kaempferol-3-O-rutinoside(9),myristic acid(10)and quercetin(11).Conclusion:P.multiflorum leaves showed good anti-inflammatory activity,and compounds 2,4,6,7,8,9,10,11 were isolated and obtained from P.multiflorum for the first time.