Abstract:

A mixture of crushed Ziziphus jujuba cv. Huizao fruits and water was homogenized and treated by microwave and ultrasonic to extract cyclic adenodsine monophosphate. The effects of homogenization speed and time, material/water ratio, ultrasonic treatment temperature and time, and microwave power and treatment time on yield of cyclic adenodsine monophosphate were investigated by single factor method. Subsequently, response surface methodology (RSM) based on a three-level, four-variable central composite rotatable design (CCRD) was employed for evaluating the interactive effects among other four variables except homogenization speed and time and ultrasonic treatment temperature, and a quadratic regression model was developed for predicting the yield of cyclic adenodsine monophosphate under various extraction conditions. The optimal extraction conditions were as follows: with a material/water ratio 0.07 g/ml, 97 s microwave treatment at 450 W followed by 28 min ultrasonic treatment at 60 ℃. Under these conditions, the yield of cyclic adenodsine monophosphate was 64.33 μg/g.

Key words: combined microwave and ultrasonic extraction, cyclic adenodsine monophosphate, response surface methodology