| The contents of three main officinal components(naringin, hesperidin and synephrine) and their changes were determined by high performance liquid chromatography (HPLC) in ten samples of fruits of medicinal hesperidium with different origins and different harvest periods such as lvyi zhishi[Poncirus trifoliate (L.) Raf.], eyan zhishi [Poncirus trifoliate (L.) Raf.], pumello [C. grandis (L.)Osbeck], daidai [C. aurantium L. cv. 'DaiDai' ], honghe chengzhike in Shanxi Province [Citrus hongheensis Y.L.D.L.], lvyi zhike in Fujian Province [Poncirus trifoliate (L.) Raf.], zhike in Jiangxi Province [C. aurantium L. ], zhike in Hunan Province [C. aurantium L.], zhike in Shanxi Province [C. wilsonii Tan.], zhike in Sichuan Province [C. aurantium L.], and the inhibition of their extracts to tyrosinase and their mechanisms were probed; the medicinal hesperidium with different origins were preliminarily identified by randomly amplified polymorphic DNA (RAPD); which will provide scientific bases for rationally exploiting, utilizing and identifying the resources of medicinal hesperidium. The main results were as follows.1.The difference in the contents of naringin, hesperidin and synephrine was obvious in zhishi with different origins.The flavoid (the sum of naringin and hesperidin) and alkaloid (synephrine)are the main officinal substances in the four samples of fruits of zhishi such as lvyi, eyan, pummelo, and daidai,, the contents of the flavoid was higher than that of the alkaloid, taking up 58.04%—92.32% in total contents, the content of synephrine in eyan zhishi was higher than that in the other three samples of fruits reaching to 291.28mg/g, which was 5.3 times, 23.9 times and 25.2 times as that in lvyi,daidai and pummelo, respectively.Naringin was dominant taking up 97.50%~99.99% in alkaloid (sum of naringin and hesperidin) in the four samples of fruits of zhishi, its contents in pummelo was highest reaching to 138.72 mg/g, which was 3.6 times,3.1 times and 2.1 times as that in lvyi, eyan and daidai, respectively.However, the contents of hesperidin was very low in the four samples of fruits of zhishi , varying from 0.189 ~0.997 mg/g; the contents in Iiyi zhishi was the highest, reaching to 0.997 mg/g ; second eyan zhishi, daidai, 0.563 mg/g and 0.797mg/g , respectively; and pummelo lowest, only 0.189 mg/g, which was one fifth as that in lvyi zhishi.The sum of naringin ,hesperidin, synephrine was 337.18mg/g,150.45mg/g, 94.95mg/g,79.97mg/g in eyan zhishi,pummelo, lvyi zhishi and daidai, respectively, in the four samples of zhishi.2. The difference in the contents of naringin, hesperidin and synephrine was obvious in zhike with different origins.The rate of the flavoid (sum of naringin and hesperidin) was dominant among the three main officinal components determined in tested six samples such as honghe chengzhike in Shanxi Promince, lvyi zhishi in Fujian Province,zhike in Jiangxi Province, zhike in Hunan Province, zhike in Shanxi Promince, zhike in Sichuan Province, except for honghe chengzhike in Shanxi Promince, varying from 80.08% ~ 99.33 %, but only occupy 24.89% in honghe chengzhike in Shanxi Promince.The contents of naringin was far higher than hesperidin taking up 83.72%~97.69% in the flavoid (sum of naringin and hesperidin) in tested six samples of fruits, the highest in honghe chengzhike; but the absolute contents of the flavoid in zhike in Jiangxi Province was highest reaching to 59.80mg/g, the lowest in honghe chengzhike only 12.05mg/g, the former was 4.96 times as the latter, that in the other four samples ranked in zhike in Hunan Province 59.39 mg/g, zhike in Shanxi Provine 46.70 mg/g, lvyi zhishi in Fuian Provine 28.27 mg/g, and zhike in Sichuan Province 26.52 mg/g. but the contents of hesperidin in all samples were low varying from 0.29-11.63mg/g, highest in zhike in Jiangxi Province 11.63mg/g, lowest in honghe chengzhike only 0.29mg/g, the former was 40.1 times as the latter, that in the other four samples ranked in lvyi zhike in Fujian Province 2.50 mg/g, zhike in Shanxi Province 1.63mg/g, zhike in Hunan Province 1.62mg/g, zhike in Sichuan Province 1.28mg/g.The contents of naringin was 83.72%~97.69% higher than that of hesperidin in the flavoid (sum of naringin and hesperidin) in tested six samples of fruits. The contents of naringin in honghe cheng zhike was the highest among the samples.The contents of hesperidin in honghe cheng zhike was 37.21 mg/ghigher than the other five samples of fruits occupying 75.11 % in sum of three officinal components among the six samples of fruits. The contents of hesperidin ranked in zhike in Jiangxi Province (16.91 mg/g), zhike in Hunan Province (12.72 mg/g), zhike in Shanxi Province (12.02 mg/g), zhike in Sichuan Province (6.44 mg/g), lvyi zhishi in Fujian Province (0.21 mg/g).The sum of contents of naringin , hesperidin, and synephrine ranked in zhike in Jiangxi Province (88.34 mg/g) , zhike in Hunan Province (73.72 mg/g ), zhike in Shanxi Province (60.35 mg/g ), honghe cheng zhike in Shanxi Province (49.55 mg/g), zhike in Sichuan Province (34.23 mg/g) and lvyi zhishi in Fujian Province (30.97 mg/g) among the six samples of fruits.3. The contents of naringin, hesperidin, and synephrine were related to the harvest periods in zhi in Fujian Province.Medicinal Hesperidium such as eyan zhishi, liyi zhishi, and lvyizhike were derived from zhi [Poncirus trifoliate (L.) Raf.] in Fujian Province, Their contents of three main officinal components (naringin, hesperidin and synephrine) were related to the sizes and harvest periods of the fruits, the earlier harvested the fruit, the higher the contents of naringin and synephrine, the contents of hesperidin was on the contrary, the contents of naringin and synephrine ranked in eyan zhishi (45.34mg/g, 291.28mg/g), lvyi zhishi (38.85mg/g, 55.1 lmg/g), lvyi zhike (28.27mg/g, 0.21mg/g). but the contents of hesperidin ranked in lvyi zhike (2.50mg/g), lvyi zhishi (O.lOmg/g), eyan zhishi (0.56mg/g).The results above showed that the differences in the contents of naringin,hesperidin and synephrine were obvious in the tested samples of fruits of medicinal Hesperidiums from different kinds of plants and different sites of production (zhishi and zhike as Chinese herds), which was thought as one of the bases for rational utilization , deep processing (isolation and purification of the flavoid and biobases), classification and identification of the medicinal herds;in the meantime, the rational harvest periods of the fruits were decided to obtained Chinese herds with best qualities according to the different usages of the medicinal Hesperidiums.4.The inhibiting effects and their mechanism to tyrosinase of the extracts from the fruits of the medicinal Hesperidiums were defined.Tyrosinase (EC. 1.14.18.1) is a kind of multi-subunit copper-binding oxy-reductases with complicate structure, which is a key enzyme in biosynthesis of melanin forming splash. The extracts from ten tested medicinal Hesperidiums all remarkably inhibited the activity of tyrosinase. The activity of the tyrosinase declined at index with the increasing of concentrations of extracts of fruits in eight medicinal Hesperidiums except for daidai and lvyi zhike; But the inhibiting effect of the extracts to tyrosinase in daidai decreased when the amount of the extracts reached one concentration fixed. The concentrations of the extracts of fruits which decreased the activity to 50% (IC50) ranked in zhike in Sichuan Province (0.4 1 mg/ mL), zhike in Hunan Province (0.44 mg/ mL), daidai (0.49 mg/ mL), pummello (0.53 mg/ mL), eyan zhishi (0.63 mg/ mL), lvyi zhishi (0.67 mg/ mL), zhike in Jiangxi Province (0.70 mg/ mL), lvyi zhike (0.92 mg/ mL), zhike in Shanxi Province... |
PDF Full Text Request