| In order to provide a theoretical basis for industrial production, Eucommia ulmoides leaves from Hanzhong area were chosen as raw materials, which were used to study the accumulation rules and extraction methods of lignans, chlorogenic acid, flavonoids and iridoids.(1)In order to scientific, rational and efficient development and utilization of Eucommia ulmoides leaves, the contents of four major active components in Eucommia ulmoides leaves in different growth periods were detected by UV spectroscopy. The results show that the contents of the four major components were more obvious change with the seasons, and the total change trend was first increased and then decreased, the annual peak of lignin and chlorogenic acid appeared in the middle of June, the peak of iridoids appeared in late May to early June and the flavonoids peak appeared in the mid-late of September. Through the comprehensive change rule suggested: when the chlorogenic acid and the flavonoids were taken as main source, the suitable harvesting time was range from May to October. In contrast, the suitable harvesting period was range from May to August when lignans was the main source, and in the meantime when the flavonoids was taken as main source, the suitable harvesting period was range from April to July. Considering the total contents of four active components the suitable harvesting period was range from May to July.(2)Response surface analysis was used to study the effect of ultrasonic wave on the assisted extraction of lignans, chlorogenic acid, flavonoids, iridoids. The optimal extraction process parameters were:(1)Lignans: ethanol concentration 50%, the ultrasonic power 600 W, extraction temperature 75℃, solid-liquid ratio 1:20, the ultrasonic time 25 min, the yield rate of lignans was 0.917%(2)Chlorogenic acid: ethanol concentration 60%, the ultrasonic power 500 W, extraction temperature 55℃, solid-liquid ratio1:20, the ultrasonic time 25 min, the yield rate of chlorogenic acid was 2.63%(3)Flavonoids: ethanol concentration 65%, the ultrasonic power 550 W, extraction temperature 75℃, solid-liquid ratio1:20, the ultrasonic time 25 min, the yield rate of flavonoids was 2.387%(4)Iridoids: ethanol concentration 75%, the ultrasonic power 500 W, extraction temperature 65℃, solid-liquid ratio1:20, the ultrasonic time 25 min, the yield rate of iridoids was 0.322%According to the above four groups of process parameters, the comprehensive extraction process parameters were obtained: ethanol concentration 60%, the ultrasonic power 540 W, extraction temperature 70℃,solid-liquid ratio 1:20, extraction time was 25 minuts, two times. The results showed that the contents of effective components in the extracts were: lignans3.47%, chlorogenic acid 12.48%, flavonoids 12.63%, iridoids1.34%. Animal experiments showed that the effect of the comprehensive group extract were better than the other four groups.Ultrasonic assisted extraction not only improves the yield of the components, but also greatly shortens the extraction time. At the same time the ethanol concentration and extraction temperature were also reduced.(3)The extract of the each group was fed to the nutritional obese mice by filling the stomach for 30 d. The results show: Compared with high fat group, the comprehensive group had significant influence(**P<0.01) on body weight, Lee’s index, fat wet weight, fat index, TC, TG. The chlorogenic acid group had significant influence(**P<0.01) on body weight, Lee’s index, fat wet weight, TC; while it had significant influence(*P<0.05) on fat index and TG. The flavonoids group had significant influence(**P<0.01) on body weight and TC; while it had a significant influence(*P<0.05) on Lee’s index, fat wet weight, fat index and TG. The lignans group and the iridoids group also had a little effect on each index, but not significant.In conclusion, the comprehensive group, the chlorogenic acid group and the flavonoids group all had the function of reducing weight and blood fat, and the comprehensive group was the most significant. It was speculated that there may be some synergistic effect in reducing weight and fat. |
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