Microwave Assisted Extraction of Dioscorin from Gadung (Dioscorea Hispida Dennst) Tuber Flour

Gadung (Dioscorea hispida Dennst) tuber contains dioscorin, an alkaloid with high angiotensin converting enzyme-inhibitory capacity. In this research, dioscorin was extracted using microwave assisted extraction (MAE). The objectives of this research were to investigate the influence of ethanol concentration (75% to 96% w/w), solvent-material ratio (10: 1 to 20: 1) and microwave power (100 W to 400 W) on the extraction yield, and to develop a mathematic model to represent that process. The optimum condition for this process was extraction using 85% aqueous ethanol at solvent-material ratio of 12.5: 1, and microwave power of 100 W for 20 min. The mathematic model agreed well with the experimental data with average error of 2.96%.