Riyadh A.S. Thabit¹, Xiang-Rong Cheng¹, Nabil AL-hajj¹, Hua-Wei Shi¹, Xue Tang¹, Guo-Wei Le^1,

This study aims to determine the best extraction conditions and find out the effects of solvent type (ethanol, aceton, and ionic liquid (1-butyl-3-methylimidazolium bromide) [BMIM] Br), time (20–60 min), and microwave power (200–600 w) on antioxidant activity and total tannins (TT) of Geum japonicum. The three parameters, type solvents, extraction time and microwave power, were optimized using the Boxe Behnken design (BBD) with a quadratic regression model built by using response surface methodology (RSM). The experiments were carried out according to 17 runs with 3 variables and 3 levels for the optimization. The extracts were analyzed by spectrophotometeric methods for the antioxidant and (TT). The optimal extraction conditions were determined as follows: [BMIM]Br), microwave power 437.07 w, extraction time 36.89 min for the best antioxidant 92.24% and TT 2.44 mg GAE/g in these conditions. While the experimental maximum antioxidant was 91.5 ± 2.12 and TT was 2.72 ± 2.34 mg GAE/g of the G. japonicum extract, which matched with the predicted values. Results showed that [BMIM] [Br] solvent are more efficient in the extraction of antioxidant and TT compare with ethanol and aceton solvents. This study confirmed that the [BMIM] [Br], time 36.89 min and power 437.07 w were the most efficient for extraction of antioxidant and TT.

response surface methodology, microwave, [BMIM] [Br], Geum japonicum, antioxidant, total tannins