Technology optimization for extracting total flavonoids from citrus peel by enzyme-assisted technique

In order to make full use of agricultural waste materials-citrus peel and increase the extraction efficiency of total flavonoids from citrus peel, the influences of extraction time, extraction temperature, pH value and the mass ratio of cellulase to material on the yield of total flavonoids from citrus peel with the enzyme-assisted extraction technique were studied according to the central composite experimental design based on the single factor experiments. One mathematical model established and analyzed by response surface methodology(RSM) was adequate to describe the relationships between the studied factors and the response of total flavonoids extraction yield. Based on the canonical analysis, the optimum extraction conditions were obtained as follows: the added ratio of cellulose 0.55%, the extraction time 123 minutes, pH value 4.4 and the temperature 48℃. Under the optimized extraction conditions, it can be included that the flavonoids yield is (3.51±0.13)% (n=3), which is close to the estimated value 3.62% attained by using regression model. This model can be used to predict the experiment results well.