Optimization of ultrasonic- assisted extraction of polyphenol from Carambola by response surface methodology

The response surface methodology was used to optimize ultrasound- assisted extraction of total polyphenols from Carambola.With Carambola as raw material,the extraction rate of total polyphenols for evaluation index,then based on single factor experiment,an ultrasonic procedure for the extraction of total polyphenols from carambola was established.A three- level- four- factor test was employed in this study to optimize the factorial parameters( ultrasonic time,ethanol concentration,ratio of solvents to raw material and ultrasonic temperature) by employing Box- Behnken design of response surface methodology and Design Expert 8.05 b software was used to analyze test data.The result showed that the best ultrasonic extraction technology conditions were as follows:ultrasonic time 31 min,alcohol concentration 59%,ratio of solvents to raw material 53 ∶ 1 m L / g,ultrasonic temperature 60 ℃,the carambola total polyphenols obtained rate was 28.5 mg / g.The experimental vaule was basically agreed with the predictive value of response surface analysis.