LE PHAM TAN QUOC1,2; NGUYEN VAN MUOI1
1 Can Tho University, College of Agriculture and Applied Biology, Department of Food Technology, Campus II 3/2 Str., Ninh Kieu, Can Tho, Vietnam
2 Industrial University of Ho Chi Minh City, Institute of Biotechnology and Food Technology, 12 Nguyen Van Bao, Go Vap, Ho Chi Minh, Vietnam
Quoc, Le P. T. and N. V. Muoi, 2018. Ultrasound-assisted extraction of phenolic compounds from Polygonum multiflorum Thunb. roots. Bulg. J. Agric. Sci., 24 (2): 229–235
The goal of this study is to examine the influence of type of solvent (acetone, ethanol, methanol, and water), raw solvent/material ratio (20/1–60/1, v/w), solvent concentration (30–80%, v/v), temperature (30–70°C), time of extraction (10-30 mins) and power consumption of 550 W on the extraction yield of total phenolic compounds (TPC) and antioxidant activity (AC) from Polygonum multiflorum Thunb. roots. TPC and AC were determined by the Folin–Ciocalteu assay and DPPH assay. The optimal conditions for extraction process were 60% acetone-water mixture as solvent, solvent/material ratio of 30/1, extraction temperature of 60°C and extraction time of 15 mins. TPC and AC obtained were approximate 43.28±0.54 mg GAE/g DW (Dry weight) and 343.88±3.06 µmol TE/g DW, respectively. The effect of ultrasound-assisted extraction (UAE) on structure of materials of Polygonum multiflorum Thunb. root was observed by scanning electron microscopy (SEM). HPLC method was employed to determinate some main phenolic compounds including catechin, gallic acid, and resveratrol.