Extraction, Purify And Antioxidation Of Flavonoids In Citrus Fruit Peels

Citrus fruit is one of the biggest yield of fruit in the world,peel is their maily byproduct and it takes 20～40% output in the total citrus.The research use citrus fruit peel as test material and studied on extration and purification of flavonoids in citrus fruit peels.At the same time,Antioxidation activity was studied. UV spectrophotometer were used to measure the concentration of total flavonoid.The results was reported as following:The article sutdied on different extraction methods:water bath extraction, micro-wave extraction and supersonic extraction. Influencing factor:Ethanol concentration,extracting time, liquid-to-solid ratio, extracting temperature,micrwave power,supersonic power were studied. Through mono-factor anlysis with different extration methods,the results show that supersonic extraction has the optimal rate of extraction. Using central composite rotatable design and second order quadratic equation to determine the optimize process of flavonoids extraction by supersonic.By analyzing the response surface plots and their corresponding contour plots as well as solving the quadratic equation,the optimal processing for supersonic extraction were 62.08% ethanol,62.17min supersonic time,37.59 liquid-solid ratio.The predicted result for the rate of flavonoids extraction was 1.23%. Variance analysis is very significance in the Quadratic equation model.Four macroporous adsorption resin were used to purify flavonoids of citrus citrus peel. Through static adsorption and desorption experiment,using the rate of absorption and desorption as evaluating indicator,finally got AB-8 was the best in the four different resins and the resin got its adsorption equilibrium in five hours,the optimal dynamic adsorption processing parameter of AB-8 resin were flavonoids solution concentration is 1.22mg/mL,pH is 3.5. The optimal dynamic desorption processing parameter are flow rate is 1BV/h, ethanol concentration is 70%. Purity of total flavonoids was increased from 8.7% to 38.5%. AB-8 resin can be used to purify flavonoids of citrus peel.The antioxidation activity of citrus peel flavonoids before purifying and after purifying was studied, The results was reported as following:when flavonoids addition was 0.4mg,the effect of scavenging hydroxyl free radical and superoxide anion free radical were vitamin c>citric acid>purified flavonoids>rough flavonoids, the effect of scavenging DPPH free radical was vitamin c>purified flavonoids>citric acid>rough flavonoids. The effect of scavenging the three free radical was intensified while the addition of puried flavonoids increased,(flavonoids addition between 0.3～1.5mg);The different antioxidant activity was studied in lard oil.The effect of antioxidant was BHT > rough flavonoids > purified flavonoids>rutin>bland.The effect of antioxident in lard oil was intensified while the addition of puried flavonoids increased.