Studies On The Content Changes Of Main Flavones,Their Acid Hydrolysis And Extraction Of PMFs In Hu You Fruits

Changshan Huyou(Citrus Paradisi cv.Changshan Huyou)originated in Hujia village of Qingshi township in Changshan county,Zhejiang province.Changshan Huyou is known as the " The No.1 hybrid orange in China",because of its fine qualities such as resistance to dry,cold and tolerant to storage.Huyou fruits has many effects,such as clearing away heat and toxic materials,preventing phlegm from forming and stopping coughing,stabling blood sugar,dispelling the effects of alcohol and restoring consciousness,detoxifying and beautifying,prolonging life and so on.A recent studies showed shown that flavonoids in Huyou fruits was the main active ingredient.However,there are few studies on content analysis of flavonoids during the growth of Huyou fruits and their hydrolysis.This work monitored the content of flavonoids during the growth of Huyou fruits from fifteen village of Changshan County,extracted successively according to the polarity of flavonoids of which the optimum conditions of acid hydrolysis for the highly polar flavonoid glycoside for water extraction were investigated,and the antioxidant abilities of hydrolysate were determined,and low polar polymethoxylated flavones was extracted optimally by orthogonal experiment and puried preliminarily with petroleum ether.This work could provide a reference for the development of health care products rich in flavonoids of Huyou fruits.The contents of four flavonoids of narirutin,naringin,hesperidin and neohesperidin were monitored during the growth(6-10 month)of Huyou fruits from fifteen village of Changshan County.The results showed that the order of total content of four flavonoids in Huyou fruits from fifteen villages of Changshan County was:hongqi village>tonggongshan>xinpinzhong>taigongshan>xiaobaishi village>dongan>dingjiawu>taigongshan(zhao)>wuli>daqiao>jianglianqu village>qingshi>laowu>gedi>longrao.The sequence of total content of four flavonoids in Huyou fruits during 6-10 month was:early June>late June>early July>September>late July>early August>late August>October.Naringin(54.51mg/g)and neohesperidin(39.61mg/g)hold the main part in flavonoids,and narirutin(8.97mg/g)and hesperidin(7.90mg/g)hold minor.High polar flavonoids in Huyou fruits was hydrolyzed by hydrochloric acid solution,by the single-factor research and orthogonal design,the influencing sequence of various factors for hydrolysis rate of naringenin was:hydrochloric acid concentration>hydrolysis temperature>solid-liquid ratio>hydrolysis time;the influencing sequence of various factors for hydrolysis rate of hesperitin was:hydrolysis temperature>solid-liquid ratio>hydrochloric acid concentration>hydrolysis time;the optimum acid hydrolysis conditions were obtained as follows:the hydrochloric acid concentration 1.0mol/L,hydrolysis tempera-ture 70 ?,hydrolysis time 60 min,solid-liquid ratio 1:30,under these conditions,the hydrolysis rate of naringenin is 19.02%and the hydrolysis rate of hesperetin is 18.11%.Comparative study the antioxidant activity of flavonoids in Huyou fruits and its hydrolysate by the method of DPPH(1,1-Diphenyl-2-picrylhydrazyl2,2-Diphenyl-l-(2,4,6-trinitro-phenyl)hydrazyl)and ABTS(2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulpho-nate).The results indicated that flavonoids in Huyou fruits and its hydrolysate possessed strong antioxidant activities against DPPH and ABTS free radicals,the IC50 on DPPH radical of flavonoids and its hydrolysate were 10.174mg/mLand 4.411 mg/mL,the IC50 on ABTS radical of flavonoids and its hydrolysate were 7.389mg/mL and 2.069mg/mL,the ability of flavonoids hydrolysate to scavenge DPPH and ABTS free radicals is significantly stronger than flavonoids at the same concentration.Low polar polymethoxy flavonoids in Huyou fruits was extracted by utrasonic-assisted method,according to the orthogonal test design based on the single factor experiments,the effecting order of various factors on extraction rate of nobiletin and tangeretin was:ethanol concentration>solid-liquid ratio>extraction time>extraction temperature;the optimum extraction conditions were obtained as follows:60%ethanol,extraction temperature 70 ?,extraction time 90 min,solid-liquid ratio 1:40,and with the best conditions,the extraction rate of nobiletin is 0.278mg/g and the extraction rate of hesperetin is 0.144mg/g.The preliminary purification of PMFs crude extracts by organic solvent extraction was studied.Extracted the PMFs with petroleum ether and the contents was obtained by HPLC analysis.After preliminary purification,the total yield of PMFs was 1.12mg/g,the purity of nobiletin(24.98%)and hesperetin(13.15%)were higher than the crude extract's purity.