| Eucommia ulmoides is one unique economic species and valuable herbal medicine in China.In China,E.ulmoides has a wealth of resources.E.ulmoides bark is a traditional medicine,however the resources of E.ulmoides bark are scarce,high production costs,which caused the death of E.ulmoides because of excessive logging.Modern research has been confirmed that the medicinal functions of E.ulmoides leaves and barks performe roughly same,owing to the fact that the active ingredients in the extracts of them are also basically similar.E.ulmoides leaves are rich resourses for bioactive compounds.Due to the larger yields of E.ulmoides leaves,timely and proper harvesting,and harmless for the growth of the tree.E.ulmoides leaves mostly developed for nutritional supplements,feed additives in domestic and foreign markets recent years.E.ulmoides leaves as raw material in make Chinese medicines is also less,so that researches on E.ulmoides leaves have drawn much attention in production and application,since the E.ulmoides leaves were formally contained in the "Chinese Pharmacopoeia" in 2005.In this paper,the main goal of this project is that using the E.ulmoides leaves as the material basis aims to obtain the target components of asperuloside,geniposidic acid and chlorogenic acid compositions,focusing on the national forestry economy and social development of the major needs.The target components of E.ulmoides leaves were extracted by helical extrusion pretreatment-ultrasound-assisted method,and the response surface was used to optimize the extraction process.Macroporous resins were used to enrich asperuloside,geniposidic acid and chlorogenic acid from the extracts.The main contents of this project are as follows:1.A method for the simultaneous determination of geniposidic acid,asperuloside and chlorogenic acid by HPLC was established.The chromatographic conditions were:column:Agilent 5 TC-C18(5 μm,4.6 mm × 250 mm);column temperature:25 ℃;detection wavelength:237 nm;injection volume 10 μL;flow rate 1 mL/min;mobile phase composition and elution ratio:0.5%phosphoric acid(A):methanol(B);gradient elution:0-40 min,5%-32%(B);40-41 min,32%-60%(B);41-51 min,60%(B);51-52 min,60%-5%(B);52-60 min,5%(B).2.Response surface optimization is used in extraction conditions for the best extraction of asperuloside,geniposidic acid and chlorogenic acid form E.ulmoides leaves.The optimal extraction conditions were as follows:70%(v/v)ethanol aqueous solution,liquid-solid ratio of 20 mL/mg,ultrasonic frequency of 80 kHz,ultrasonic irradiation power of 200 W,40 min,temperature of 50 ℃.The yield of asperuloside,geniposidic acid and chlorogenic acid and were 266.78±13.34 μg/g,892.37±46.96 μg/g and 2418.05±53.68 lg/g,respectively.The purity3.of asperuloside,geniposide and chlorogenic acid were 1.66%,1.74%and 7.79%,respectively.4.The macroporous resins were used to optimize the enrichment parameters of asperuloside,geniposidic acid,and chlorogenic acid after screw extrusion pretreatment followed with ultrasonic-assisted extraction.Eight kinds of macroporous including HPD-600,AB-8,X-5,HPD-400,ADS-17,HPD-80,HPD-450A,and D-4020 were studied and compared by using the asperuloside,geniposidic acid and chlorogenic acid absorbed and desorbed capabilities as criterion.And as a conculsion,HPD-600 was selected as the best resin for the enrichment of asperuloside,geniposidic acid and chlorogenic acid.5.The optimum adsorption parameters for macroporous resin HPD-600 were as follows:adsorption temperature of 25 ’C,sampling volume of 50.4 mL,sampling flow rate of 2 BV/h,loading pH of 4 and mass concentration of added sodium chloride 2%.and the maximum adsorption amount of asperuloside was 0.55 mg/g,and the maximum adsorption amount of the resin to geniposide was 1.18 mg/g,and the saturation adsorption of chlorogenic acid was 4.40 mg/g.Optimum desorption parameters for HPD-600 macroporous resin:50%ethanol elutes at 2 BV/h.The resolution of asperuloside was 81.01%,geniposide was 90.16%and the resolution of chlorogenic acid was 95.72%.The purity of asperuloside,geniposide,and chlorogenic acid enriched by macroporous resin were 7.34%,8.01%,and 39.31%,respectively.Screw extrusion pretreatment was completely breaking down the plant cell wall,so that the target products were extracted from cells during the following to ultrasonic extraction,and then purified by using macroporous resin.We concluded that screw extrusion pretreatment is a new,fast,green,effective,and low-cost method. |
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