Extraction And Purification Of Polysaccharides From Mulberry Leaves And Its Hypoglycemic Activity

The polysaccharides from mulberry leaves can cure diabetes significantly.Therefore,extraction and purification of the polysaccharides from Mulberry Leaves and study of its pharmacological activities are echnically significant and practically valuable to develop a new drug curing,diabete.First,we have used hot water to extract mulberry leaves,at a different extraction time,extraction temperature,extraction pH,solid to liquid ratio(mulberry mass g:water volume mL)and extraction times for the single factor,to study the factors on the yield of polysaccharide,and then the water extraction process of polysaccharides was optimized by orthogonal experimental,bringing the total polysaccharides rate of 2.89%;in the ethanol precipitation process,the effects of ethanol concentration on the alcohol precipitation conditions were inspected,the best conditions of alcohol precipitation conditions were dentified,the polysaccharide content of ethanol sediments was 18.44%.In addition to process of wiping off protein,the effects of trichloroacetic acid and hydrochloric acid on content of polysaccharides and retention rates were nvestigated,we adjusted the polysaccharide solution to pH5 with trichloroacetic acid,and then adjusted the pH to 3 with hydrochloric acid,the polysaccharide content and retention rate reached to the highest,32.59%and 85.42%separately.Secondly,single factor experiment of macroporous resin for optimizating purification of mulberry leaves polysaccharide was carried out,The optimum process conditions were obtained,retention rate of of polysaccharide was 81.54%and polysaccharide content was 35.14%.In addition,the polysaccharide purified by chitosan flocculant was examined,single factor experiments and response surface experiment were used to obtain the best flocculation process of polysaccharide.In this process,the retention rate of polysaccharide was 90%or more,and content rate was up to 61.59%.By means of components determination of polysaccharide samples flocculation by chitosan,we found the levels of inorganic molecules were very high,reaching to 23.88%,followed by protein content(7.83%).Finally,through the establishment of alloxan diabetic mice model of pharmacological activity tests,we found that mulberry leaves polysaccharide(purity quotient 59.22%)can be very effective in lowering blood glucose levels in diabetic mice,the blood glucose inhibition rate reached 81.14%,it can effectively reduce serum and liver MDA content,be better than metformin,with significant hypoglycemic and antioxidant synergy.This research gives the necessary basic data and reference for the separation and purification of the polysaccharide from mulberry leaves.For the hypoglycemic activity of mulberry leaves polysaccharide,we provided an experimental basis.