The Research On Extraction, Purification And Liver-protective Function Of Active Ingredient From Kiwifruit Roots

Kiwifruit, which belongs to Actinidia chinensis genera, deciduous wood liana, is widely distributed in China. The root from kiwifruit, which is rich in polysaccharide, terpene, tannide, steroid and flavone, has effects on strengthening stomach, clearing heat, removing toxicity, removing dampness by duresis and expelling wind. So it will be very meaningful to study on extracting active ingredient from kiwifruit root and to study on liver-protective function of kiwifruit extract.The wild kiwifruit root and planted "Miliang-Ⅰ" kiwifruit root from western Hunan were used as raw materials. The technology of extraction, isolation and purification of kiwifruit root polysaccharide and ursolic acid were studied and liver protective activity of kiwifruit root extract were evaluated in this paper. The main results were shown as follows:1. The optimal microwave extraction process of polysaccharide in wild kiwifruit was determined by response surface method. That is the ratio of kiwifruit root to water(g:mL) 1.8:30, extraction temperature 61.5℃, extraction time 33.5 min. Under these conditions, the yield rate of polysaccharide was 12.34%, and its actual yield rate was 12.34±0.01%, RSD value was 1.28%(n=5).2. After elementary purification of the crude extracts from wild kiwifruit root, the raw polysaccharide was purified by DEAE-cellulose, the best eluants was the solution of NaCl. Through DEAE- cellulose the raw polysaccharide was purified to three ingredient PK1,PK2,PK3, their yield rate was 62.87%,8.24%,15.39% respectively.3. The optimal microwave extraction process of ursolic acid from wild kiwifruit was determined by response surface method (RSM). That is the optimum extract condition were alcohol concentration 72.8%, the ratio of kiwifruit root to alcohol (g:mL) 4.2:25, extract time 18.9 min, extract temperature 90.0℃. Predict theoretical yield rate of kiwifruit root ursolic acid was 5.68%, and its actual yield rate was 5.66±0.01%, RSD =1.43%(n=5).4 Through TLC experimental study, ursolic acid after ethyl acetate extraction can be achieved initial purification. Through the study on eluting solvent ratio of silica gel column chromatography on and the size of silica gel particle,it is found that when the ratio of chloroform to methanol is 18:1, the particle size of 100～200 mesh, can make ursolic acid purity highest concentration, reaching more than 85% and the yield rate is over 65%.5 The wild kiwifruit root and "Miliang-Ⅰ"kiwifruit root from western Hunan were used as raw materials. The crude polysaccharide and crude tri-terpenoid extracted from wild kiwifruit root and water extracts were used to evaluate the liver-protective function by testing AST,ATL,MDA,SOD in serum of mice. The results were as follows: compared with the model group, each group had dissimilar degree of protecting liver function, which tri-terpenoid was better than the other ingredients, water extracts was better than raw polysaccharide. Tri-terpenoid from wild kiwifruit roots were closer to normal than "Miliang-Ⅰ" kiwifruit roots did, which reveal that the liver protective function between different species is different----the tri-terpenoid from wild kiwifruit roots was better than "Miliang-Ⅰ" kiwifruit roots. There is significant difference among different dose. High dose of tri-terpenoid from both wild kiwifruit roots can improve SOD and decrease MDA,AST,ALT significantly. Meanwhile, High dose of tri-terpenoid from both wild kiwifruit roots and "Miliang-Ⅰ"kiwifruit were the best dose to protect liver from CCl4 liver injury, middle dose and low dose were followed by it.