Optimization of ultrasonic- assisted extraction process of chlorophyll from Pueraria lobata using response surface methodology

In order to optimize the ultrasound extract of Pueraria lobata leaves chlorophyll process conditions, four factors were selected which had effect on extraction rate of chlorophyll, that was ratio of liquid to material, ultrasonic extraction temperature, ultrasonic extraction time, extraction solvent species.In the basis of single factor experiments, these four factors were optimized using response surface analysis based on a four- variable, threelevel Box- Behnken design. The results showed that the optimum preparation technology for ultrasound extract of Pueraria lobata leaves chlorophyll were: ratio of liquid to material was 106 ∶ 1 ( m L·g- 1) , ultrasonic extraction temperature was 54℃, ultrasonic extraction time was 31 min, extraction solvent species ethanol ∶ acetone ( 1.9 ∶ 1) .Under the optimal extraction condition, the chlorophyll productivity was 0.691%.