Optimization of extraction process conditions of oleoresin from Zanthoxylum bungeanum by response surface methodology

Zanthoxylum bungeanum as the research object, with the oleoresin extraction rate as a measure indicator. Three extraction parameters including liquid-solid ratio, ethanol concentration and output power were optimized using central composite design and response surface methodology based on single factor investigations for achieving maximum the oleoresin extraction rate. The interaction of the respective variables and their influence on the extraction rate were studied by using Box-Benhnken central composite design and response surface analysis theory, the simulated quadratic polynomial regression equation of prediction model was set up. Under the condition of extraction temperature 80℃ and extraction time of 5min, the liquid-solid ratio 12 ∶1, ethanol concentration 56% , ultrasonic output power of 210W. Under these conditions, the average oleoresin extraction rate was 33.60%, compared to the theoretical value, the relative error was 1.73%. Optimized by response surface regression equation derived some practical significance.