Bioguided Fractionation of Polygonum alpinum. and Isolation and Structure Elucidation of Active Compounds

Abstract

Bioguided fractionation of the methanol extract of aerial parts from Polygonum alpinum. L. (Polygonaceae) was investigated using the exudation phase of inflammation in aseptic arthritis model, which is produced by carrageenan and radical-scavenging properties. Flavonoid-containing fractions showed anti-inflammatory and radical-scavenging activities. Therefore, isolation and structure elucidation of flavonoids were carried out. The eight flavonol glycosides, which were quercetin 3-O.-arabinofuranoside (= avicularin) (1), quercetin 3-O.-β.-glucuronopyranoside (2), quercetin 3-O.-α.-rhamnopyranosyl (1 → 6)-β.-glucopyranoside (3), quercetin 3-O.-β.-galacturonopyranoside (4), quercetin 3-O.-β.-glucopyranoside (5), kaempferol 3-O.-β.-galactopyranoside (6), quercetin 3-O.-β.-galactopyranoside (= hyperoside) (7), and myricetin 3-O.-β.-galactopyranoside (8), were isolated from the methanol herb extract of Polygonum alpinum.. The structures were established by spectroscopic methods.

Keywords:

• Anti-inflammatory activity
• flavonol glycosides
• Polygonaceae
• Polygonum alpinum
• radical scavenging effect