Optimization of Microwave-Assisted Extraction to Obtain Optimum Antioxidant Activity and Anthocyanin Concentration from Myrmecodia pendens Tubers Using Response Surface Methodology

Background: One of the major antioxidants in Myrmecodia pendens (sarang semut) tubers is anthocyanin. Objective: To obtain antioxidant activity and anthocyanin concentration from sarang semut optimally through an appropriate method. Materials and Methods: Microwave-assisted extraction (MAE) was chosen because of its brief extraction time (ET), saving solvents, and being inexpensive compared to conventional extraction methods. Experiment design was prepared using response surface methodology. 1,1-diphenyl-1-2-picrylhydrazyl and reducing power method were used for the determination of the antioxidant activity, while the Association of Analytical Communities official method 2005.02 was used for the anthocyanin concentration calculation. Results: It was found that the optimum antioxidant activity was obtained at 80% ethanol, sample-to-solvent ratio (S/S ratio) 1:12, ET 10 min, and MAE power 50%. Meanwhile, the optimum anthocyanin extraction was obtained at 80% ethanol, S/S ratio 1:8, ET 3 min, and MAE 10%. Conclusion: The optimum condition of antioxidant activity and anthocyanin concentration was the same at the solvent used, yet different at the S/S ratio, ET, and power level which open further research to support this study.