Abstract: Based on the preliminary experiments, a three-variable, three-level Box-Behnken design was performed to study microwave-assisted extraction of genistein from the roots of pigeon pea. The optimum parameters were as follows: extraction temperature 68 ℃, liquid/solid ratio 32∶1 mL·g^-1, ethanol concentration 78%, extraction power 700 W and extraction time 15 min. Under the optimal conditions, the average extraction yield of genistein was 0.465±0.032 mg·g^-1. This study is significant for the application of microwave extraction technology and utilization of the pigeon pea root.

Key words: pigeon pea roots, genistein, microwave-assisted extraction, Box-Behnken design