DOI: https://doi.org/10.55373/mjchem.v25i4.21

Keywords: Polygonum multiflorum; total phenolic content; total flavonoid content; radical scavenging activity, Response Surface Methodology

Abstract

Response surface methodology (RSM) was used to optimize the extraction conditions for the determination of total phenolic content (TPC), total flavonoid content (TFC) and Antioxidant Activity (DPPH) in the roots of Polygonum multiflorum Thunb. using Microwave-Assisted Extraction (MAE). The process variables were extraction temperature (40 - 60 oC), extraction time (30 - 60 min), ethanol concentration (30 - 70 %) and microwave power (300 - 500 W). The results showed that temperature, time, ethanol concentration and microwave power had significant impacts on TPC, TFC and DPPH. The optimum extraction conditions obtained with RSM were: extraction temperature of 53 oC, extraction time of 49 min, ethanol concentration of 48 % and microwave power level of 420 W. The experimental values obtained for TPC, TFC and DPPH radical scavenging activity were 34.15 ± 0.2 mg GAE/g, 6.52 ± 0.15 mg QE/g and 93.82 ± 0.3 %, respectively.