Studies On Extraction And Purification Of Hesperidins From Bingtang Navel Orange Peels And Fermented Bingtang Navel Orange Juice

Using peels of Bingtang navel oranges as raw material, system studies about extraction, isolation and purification of hesperidin have been conducted with methods of cellulase, microwave and cellulase-microwave. Then a lactobacillus fermented beverage from Bingtang navel orange juice were developed. The main results were summaried as follows.(1) In order to optimize extraction process of hesperidin, methods of single factor experiment and orthogonal design were adopted. Extraction processes were discussed, using cellulase and microwave to extract hesperidin, first separately, then combined. The optimum parameters of cellulase and microwave extraction were obtained. For the cellulase-microwave extraction, hesperidin yield was 6.41% and RSD was 0.39%(n=3), with parameters as follows. The ratio of cellulase/orange peel was 3%(g/g); pH value was 5.5; cellulase treatment time was 90 min; cellulase treatment temperature was 45℃; microwave output power was 560 W; microwave treatment time was 25 s; ratio of solid/liquid was 1:50; and ethanol concentration was 80%. It showed that the cellulase-microwave extraction technology was an effective way to extract hesperidin. Under the optimum condition, the content of hesperidin in total solids was 16.18%.(2) The purification of hesperidin from peels of Bingtang navel oranges with seven kinds of macroporous resins was studied (models, respectively:AB-8, D-151, S-8, HP-20, HPD-500, HPD-600, H-103). Results showed that the AB-8 macroporous resin was the best purification resin. Then the dynamic adsorption characteristics of AB-8 resin were studied. Results showed that the maximum adsorption capacity was 12.02 mg/g. Using single factor experiment method, appropriate purification parameters were obtained as follows. The sample solution pH value was 4.5; the sample flow rate was 60 mL/h; the sample concentration was 9 mg/mL; the elution flow rate was 60 mL/h; the elution volume was 3 BV; and the elution concentration was 80%. Under the optimum conditions, the purity of hesperidin in sample was increased from 16.18% to 33.33%; the relative standard deviation was 3.775%(n=5); and the refined multiples was 2.06.(3) The product purity was determined further by high performance liquid chromatography (HPLC) method. HPLC standard curve equation for hesperidin was as follows:y=22.599x+5.534, R2=0.9985. It displayed a good linear relationship in the range of 0.832～4.160μg. According to the standard curve equation, the hesperidin purity reached more than 30%.(4) Lactobacillus fermented beverage from Bingtang navel orange was developed and studied. The fermention formula, fermentation conditions and the optimal technological parameters of fermented beverage formula were gained through orthogonal experiment L9(34). The better fermention formula was milk 4% and glucose 2%. The optimal fermentation conditions were as follows. Inoculation mass was 4%; fermentation temperature was 42℃; and fermentation time was 36 h. The optimum formulae of the fermented beverage were as follows (additive amount, g/mL). Sucrose was 4%; citric acid was 0.04%; and CMC-Na was 0.2%. The finished products were homogenous and stable with better flavor and taste. By optimization, the content of lactic acid in beverage was 0.75%; and the lactic acid bacteria number was 1.8×106/mL.