Studies On Extraction Of The Hesperidin From Orange Peel And The Limonin In Citrus Seeds

The orange peel and citrus seeds are the main by-products in citrus further processing, and hesperidin and limonin are the most important effective components. the methods of ethanol extraction, alkali extraction and acid precipitation of hesperidin in the orange peel, and ultrasonic extraction with acetone, ethanol extraction of limonin in citrus seeds were studied in this paper, the main research contents and results were as follows.1 The optimization extraction conditions of the hesperidin from theorange peelHesperidin in orange peel by the methods of ethanol extraction, alkali extraction and acid precipitation were studied. By using the principle of the aluminium nitrate-hesperidin complexes formed in water-methanol systems, hesperidin was determinated by spectropHotograpHy. The optimum process conditions obtained by response surface analysis （RSM,Response surface methodology） were as follows: the regression model of the hesperidin extraction with 95% ethanol was accurate and effective, 70℃, 4.0h and liquid-to-solid ratio 25ml/g, the extraction rate of hesperidin was 20mg/g under the optimum condition. The experiment study and the return equation analysis showed that the marked degree were: liquid-to-solid ratio > extraction temperature > extraction time.2 The optimization extraction condition of the Limonin in Citrus Seeds by the acetone extraction and the ultrasound-assisted extraction ofacetoneThe extraction and separation processes, detection condition of the limonin in citrus seeds were studied. Degrease the materials by petroleum ether, extraction condition by acetone and ultrasonic extraction using selected orthogonal design L₉ （3⁴） were optimized, and the optimum condition were as follows: （1） The optimization extraction condition of acetone extraction: temperature 65℃, time 7h and liquid-to-solid ratio 80ml/g, the average yield of limonin was 362.34mg/kg. （2） The optimization extraction condition by ultrasound-assisted extraction of acetone: temperature 40℃, time 60min and liquid-to-solid ratio 90ml/g, ultrasonic power 60W, the average yield of limonin was 355.72mg/kg. The reasonsfor of lower extraction rate of ultrasound-assisted extraction maybe due to the less ultrasonic time.3 The optimization extraction conditions of the Limonin from CitrusSeeds by ethanol extractionExtraction from the limonin from citrus seeds by the methods of ethanol extraction was studied, and the extraction conditon was optimized by the Box-Behnken mode of response surface analysis （RSM, Response surface methodology）. The optimum extraction condition were: ratio of liquid to solid 20ml/g, extracting time 90 minutes, extracting temperature 70℃, and the ethanol concentration 90%, the practical extraction rate was 4. 7052 mg/g. The ethanol concentration, ratio of liquid to solid and extraction time were the significant impact factors of the limonin extraction by ethanol solution. The return equation analysis showed that the marked degree were: liquid-to-solid ratio> ethanol concentration > extraction time>extraction temperature. At the same time, the extraction of limonin was verified by High Performance Liquid ChromatograpHy （HPLC）.