Phenolics from Mikania micrantha and Their Antioxidant Activity

2018-11-23 本站

题目:Phenolics from Mikania micrantha and Their Antioxidant Activity


作者:Li-Mei Dong 1,†, Xu-Chao Jia 2,†, Qing-Wen Luo 3, Qiang Zhang 3,Bi Luo 3,Wen-Bin Liu 3,Xu Zhang 1,Qiao-Lin Xu 4,*, Jian-Wen Tan 1,3*,

单位:1. State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (L.-M.D.); (X.Z.);2. Key Laboratory of Functional Foods, Ministry of Agriculture/Guangdong Key Laboratory of Agricultural Products Processing/Sericultural & Agri-food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, China;;3 .Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; (Q.-W.L.); (Q.Z.); (B.L.); (W.-B.L.);4 .Guangdong Provincial Key Laboratory of Bio-control for the Forest Disease and Pest, Guangdong Academy of Forestry, Guangzhou 510520, China*. Correspondence: (Q.-L.X.); (J.-W.T.);Tel.: +86-208-702-9780 (Q.-L.X.); +86-208-528-0256 (J.-W.T.)† .These authors contributed equally to this work.

摘要:  A phytochemical study on the aerial parts of Mikania micrantha led to the isolation of

two new phenolic compounds, benzyl 5-O-β-D-glucopyranosyl-2,5-dihydroxybenzoate (1) and

(7S,8R)-threo-dihydroxydehydrodiconiferyl alcohol 9-acetate (2), together with twelve known compounds, benzyl 2-O-β-D-glucopyranosyl-2,6-dihydroxybenzoate (3), 4-allyl-2,6-dimethoxyphenol glucoside (4), (+)-isolariciresinol (5), icariol A2 (6), 9,10-dihydroxythymol (7), 8,9,10-trihydroxythymol(8), caffeic acid (9), p-coumaric acid (10), ethyl protocatechuate (11), procatechuic aldehyde (12),4-hydroxybenzoic acid (13), and hydroquinone (14). Their structures were elucidated on the basis of extensive spectroscopic analysis. Except 8 and 9, all the other compounds were isolated from this plant species for the first time. The antioxidant activity of those isolated compounds were evaluated using three different assays. Compounds 1, 2, 3, 9, 10, 13, and 14 demonstrated significant 2,20-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) free radical cation scavenging activity ranging from SC50 0.31 to 4.86 µM, which were more potent than L-ascorbic acid (SC50 = 10.48 µM).Compounds 5, 9, 11, and 12 exhibited more potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (SC50 = 16.24–21.67 µM) than L-ascorbic acid (39.48 µM). Moreover, the ferric reducing antioxidant power (FRAP) of compounds 2, 5, 9, and 11 were discovered to be also comparable to or even more potent than L-ascorbic acid.

关键词:Mikania micrantha,phenolic compounds,antioxidant activity