Bioassay-guided Separation and Identification of Pharmacodynamic Constituents with Nitrite-scavenging Effect in Aquilaria sinensis Leaves

摘要

To explore the pharmacodynamic constituents with nitrite-scavenging effect in Aquilaria sinensis leaves, a new food raw material, applying bioassay-guided method by using UV spectrophotometry, scavenging rates of crude extracts of wild and cultivated A. leaves with different solvents, each polar fraction of the crude extracts and each cut fractions from the n-butanol fraction were tested. It is disclosed that scavenging effect of the crude extract from wild A. leaves was better than that from cultivated. n-Butanol fraction of the crude extract from wild A. with 70% acetone displayed the best scavenging effect among all the counterparts. Mangiferin (1) and 2-O-α-L-rhamnopyranosyl-4, 6, 4'-trihydroxybenzophenone (2) were identified as the two most active compounds with scavenging rate up to 29.4±0.7% and 24.6±0.8%, at the conditions of pH 3.0, 37℃ and 30 min treatment, respectively.