Optimization of Extraction of Phenolic Content from Conyza bonariensis.

This study aims to find out the effects of solvent type (ethanol, water, and ionic liquid (1-butyl-3-methylimidazolium bromide)[BMIM]Br), time (30-90min), and microwave power (200- 600w) on extraction rate, antioxidant activity, and total phenolic content (TPC) of Conyza bonariensis. The functional components from C. bonariensis were extracted using high efficient microwave-assisted extraction technology. The experiments were carried out according to 17 runs with 3 variables and three levels for the optimization in response surface methodology (RSM) system. The extracts were analyzed by spectrophotometeric methods for the antioxidant and TPC. The optimal conditions for extraction rate, antioxidant and TPC were determined by RSM. The Box-Behnken design (BBD) showed the polynomial. The optimal conditions, including [BMIM]Br as the solvent with 45.47 min and 300.60 w power, lead to the best extraction rate (25.94%), maximum DPPH radical scavenging (95.90%) and maximum TPC (174.18 mg GAE/g). Under these conditions, the experimental extraction rate was 25.13±0.85 %, DPPH radical scavenging was 93.8±1.67% and TPC was 171.5±1.06mg GAE/g of the C. bonariensis extract, which matched with the predicted values. [ABSTRACT FROM AUTHOR]