Studies On Extraction,Purification And Identification Of Flavonoids From Rough-peel Mandarin Peel

In this paper, the technological conditions of extraction and purification of flavonoids from rough-peel mandarin peel was studied. Then flavonoids were identified to be Neohesperidin, Naringin and Hesperidin by colour reaction and HPLC. The main experimental results were as follows:Firstly, we have found a pratical way of determining the content of flavonoids using spectrophotometry, which was depended on forming its complexes with certain metals. Determining the content of flavonoids in rough-peel mandarin peel during different times, results indicated rough-peel mandarin in September had the highest content, and using the rough-peel mandarin in October was more reasonable for extraction.Secondly, using two ways of extracting flavonoids from rough-peel mandarin peel by single factor and variance experiments. The optimum technique conditions by alcohol soaking cycle extraction were determined as follows: the material size was 20 mu, the concentration of alcohol was 40%, the ratio of material and alcohol was 1:30, the temperature was 70℃, the time of extraction was 60 minutes, the extracted ratio was 1.54% under the technology parameters. The optimum technique conditions by ultrasonic ware extraction were determined as follows: the material size was 20 mu, the concentration of alcohol was 50%, the ratio of material and alcohol was 1:50, the temperature was 50℃, the time of extraction was 20 minutes, extracted twice under the technology parameters, then the extracted ratio was 1.52%.Thirdly, the purification of flavonoids was studied after extracting flavonoids from rough-peel mandarin, the optimum conditions were as follows: using Polyamide (60-100mu), the current velocity was 2mL/min, the time of static absorption was 30 minutes, the eluting solvent was 40% alcohol, the flow rate of eluting solvent was 1mL/min, the volume of alcohol was 2BV.At last, colour reaction and HPLC were used for identifying the composition of flavonoids in rough-peel mandarin peel. Results indicated that those flavonoids were mainly Neohesperidin, Naringin and Hesperidin, and Neohesperidin with the highest content, whose content was 85%, Naringin was the second, whose content was 12.3%, then was the Hesperidin.