Study On Extraction And Purification Of Isoflavones In Trifolium Pratense

This paper take the Trifolium pratense as the research object.At first analysis active ingredients in Trifolium pratense in a preliminary; On this basis, the compara -tive study the four kinds of extracted method of isoflavones in Trifolium pratense process conditions and then using macroporous resin adsorption method to enrich and purify Trifolium pratense isoflavones; Use of supercritical CO₂ extraction technology to carry out a preliminary study on the extraction process of isoflavones in Trifolium pratense.Using Kjeldahl method to determine the content of protein in Trifolium pretense, the result is 11.32%.Using phenol-sulfate method to determine the content of polysaccharide in Trifolium pratense is 2.01%; Using supercritical CO₂ extraction method to measure the content of volatile oil in Trifolium pratense is 1.04%.By three-wavelength UV spectrophotometry to determine the content of isoflavones in Trifolium pratense is 0.283%.Take obturated microwave-assisted extraction (MAE) equipment first in extraction of isoflavones in Trifolium pratense. Effects of ethanol-water solvent, microwave power, raio of liquid to material, extraction time and extraction times on extraction rate of isflavones were investigated by single factor and orthogonal experiment.The optimum extraction conditions for isoflavones in Trifolium pratense were established as follows:70% ethanol(V/V) as solvent,ratio of liquid to material 15:1 (V/W),microwave power high fire (750w), extraction for 3 times and 1 min for each time. The extraction rate of isoflavones in Trifolium pratense was as high as 98.91%. And compare with ultrasonic extraction, refluence extraction and Soxhlet extraction in extraction process.As isoflavones to the objective product with five kinds of macroporous resin to adsorpt and separate. By static adsorption experiments result show that D101 resin is better adsorption materials to purify isoflavones in Trifolium pratense.Using D101 resin in dynamic adsorption experiments show that optimum process conditions: the test solution concentration 0.50mg/mL, pH 4-5, sample volume 2 BV, flow rate 1.0 mL/min , isoflavones desorption rate is 71.5%, the purity 26.7% when 5 BV 60% ethanol elution. Isoflavones desorption rate is 92.4%, the purity 13.2% when 5 BV 80% ethanol elution. And propose an enrichment and purification of isoflavones in Trifolium pratense new route. Take supercritical CO₂ extraction first in extraction of isflavones in Trifolium pratense. Effects on extraction rate of isflavones were investigated by single factor experiment. The optimum extraction conditions for isoflavones in Trifolium pratense were established as follows: the granule size material at 40 mu,absolute ethanol as modifier, ratio of modifier to material lmL/g,extraction temperature 40℃,extraction pressure 25Mpa,CO₂ flow rate of 1mL/min,static extraction time 60 min,dynamic extraction time 15 min, isoflavones extraction rate is 30%.Analyze isoflavones composition of SFE. Give a preparation of high purity isoflavones in Trifolium pratense new method.