Studies On The Flavonoids In Hunan Pomelo

Taken Hunan pomelo fruit drops as raw material, the ultrasonic extraction of flavonoid, one of the major bioactive ingredients, and the purification method were researched. The flavonoids in the pomelo were discussed qualitatively and quantitatively. This thesis aims to provide a theoretical basis and technical support of pomelo byproduct utilization. The main results are as follows:1. Dual-wavelength spectropHotometry was established to the flavonoid of Hunan pomelo. The detection method showed good linearity, the regression equation: y=0.0071x+0.0081 correlation coefficient R2=0.9995.2. By comparing the impact of four different extractant to the flavonoid extraction amount of the pomelo, alcohol was selected as the extractant, total extracted flavonoid was 0.99%.3. Using orthogonal experiment design, the single-factor experiment was performed for the factors that affected flavonoid extraction amount. The optimum process condition of extracting was determined. The best solution were as follows: alcohol concentration was 80%, ratio of raw material powder to extracting solution was 1:10, extracting time was 60 minutes, extracting temperature was 70℃. Extraction rate of flavonoids in Hunan pomelo of optimal test combination was 4.52%.The order that each factor affected the yield of flavonoid compound was: A>D>C>B, extracting temperature had the greatest impact, next factors were ratio of raw material powder to extracting solution and extracting solution concentration, extracting time was the last one.4.The adsorption and resolution ratio that four kinds of macroporous resin(AB-8,NKA-9,D110,ADS-17) affected flavonoid compound were compared under certain conditions. The results showed that AB-8 had a good sorption, the sorption rate was 0.70mg/mL, the recovery rate was 82.3%, so the purification of flavonoids is feasible. 5. Through dynamic adsorption and dynamic elution test, The optimal conditions for separating and purifying flavonoid were as follows:diameter height ratio(AB-8) was 1:10; adsorption velocity was 1.5BV/h; leacheate pH was 4.0; using 4BV alcohol(70%) as eluant, resolution velocity was 2BV/h; The macroporous resin must be regenerated after using 3 times.6. The quantitative operations for purified flavonoids in samples were performed. Naringin,Hesperidi,Neohesperidin Nobiletin and Tangeretin were selected as the standard samples. Through testing flavonoid chromatograpHic condition, the detection wavelength was determined. Naringin and Neohesperidin were separated in 10 minutes. The retention time of Naringin was 3.34 minute and the content was 34.87mg/g. The retention time of Neohesperidin was 3.58 minute and the content was 9.39mg/g. This method was stable and reliable after passing recovery and precision test.7. The purified flavonoids in samples were qualitatively tested by LC/MS apparatu.6 peaks were separated in 30 minutes. After preliminary identification,4 of them were flavonoid, including Narirutin,Naringin,Hesperidin and Neohesperidin. This method was stable and reliable after passing recovery and precision test.