Abstract: On the basis of one-factor-at-a-time eperiments and central composite rotary design (CCRD) experiments, the ultrasonic extraction of flavonoids from wolfberry bee pollen was optimized and a mathematical regression model was contructed. Eththanol concentration was the most significant parameter that influences extraction efficiency, followed by material-to-liquid ratio; extraction time had the weakest influence. The optimal extraction conditions were ethanol concentration of 75%, extraction time of 95 min and material-to-liquid ratio of 1:40 (g/mL). Under these extraction conditions, the average experimental extraction yield of flavonoids was 3.03% (n = 3), which was consistent with the predicted result.

Key words: ultrasonic extraction method, wolfberry bee pollen, flavonoids, extraction process