Ultrasound-Assisted Extraction of Pristimerin from Celastrus orbiculatus Using Response Surface Methodology

This paper describes the ultrasound-assisted extraction (UAE) of pristimerin from Celastrus orbiculatus. Methanol was the most effective for pristimerin extraction, followed by ethanol, ethyl acetate, n-butanol, and water. To optimize the conditions, the Box–Behnken design, a widely used form of response surface methodology, was used to investigate the effects of parameters on UAE. Several variables, such as extraction time, ultrasonic power, extraction temperature, and solvent-to-solid (S/S) ratio were investigated. The highest extraction yield of 1.843 mg/g was obtained using methanol under optimal conditions with an extraction time of 40 min, ultrasonic power of 105 W, an S/S ratio of 40 mL/g, and an extraction temperature of 52°C. The experimental values under optimal conditions agreed well with the predicted values, suggesting that UAE has good potential as an extraction method for pristimerin from C. orbiculatus.