Characterization and Antioxidant Activity of Flash-Assisted Extracted Dihydroquercetin from Wood Sawdust of Larix gmelinii Using a Response Surface Methodology

摘要

We investigate a flash-assisted extraction of dihydroquercetin (DHQ) from wood sawdust of Larix gmelinii by response surface methodology. Box-Behnken design optimized the extraction conditions, and the highest DHQ yield (6.15%) was obtained under optimal extraction conditions: FAE time (3min), extraction time (3 h), solid-to-liquid (g/mL) ratio (1:15), and ethanol concentration (75 %). After purification, the DHQ purity was 96% as determined by HPLC and was further characterized by FTIR. Purified DHQ’s antioxidant activities were confirmed in vitro by determining DPPH and ABTS radical scavenging activities and reducing Fe3+ power. In the DPPH and ABTS radical scavenging activity assays, DHQ displayed prominent antioxidant activities with low IC50 values (11.568 and 12.475 μg/mL, respectively). In reducing Fe3+ power assay, high DHQ absorbance values showed that DHQ had higher reducing power than butylated hydroxyl toluene and had nearly the same consistent power as ascorbic acid at the same doses.