Effects Of Selenium-enriched On Secondary Metabolites Of Salvia Miltiorrhiza And Extraction Of Polysaccharides

Plant is an important source of selenium for human body.Application of Selenium to crops can increase the selenium content in the food chain,improve the quality of crops,improve crop yield and enhance crop resistance.Salvia miltiorrhiza（SM）is a traditional Chinese medicine and has many important physiological functions.Its pharmacological action is similar to bioinorganic chemical properties of selenium.If SM is rich in selenium,the selenium compounds and effective components in SM may make a synergistic antioxidant effect in the human body,improving the quality of the efficacy of SM.The absorption of selenium and the effect of selenium on the plant composition is the important content of selenium-enrich experiment.The effects of different parts on the absorption and accumulation of inorganic selenium in different valence states and the effect of selenium-enrich on the secondary metabolites of SM.The extraction process,decolorization condition and the primary structure of polysaccharide in the roots of SM were studied and the effect of selenium enrichment on the quality of SM was obtained.The Se contents in the three different tissues（stem,leaf and root）and the soilweredetermined by hydride generation atomic fluorescence spectrometry（HG-AFS）.The results show that Se content in SM plants increaseswith the increase of selenium fertilizer concentration but there is no significant linearity.The Se content in stem of SM plant is the highest,followed by leavf and root.Partial selenium ismoved and exchanged to soil by plant and the Se content of soil increases with the increase of dosage of Se fertilize.The content of Se in root of SM sprayed with selenate and its corresponding soil arehigher compared with SM sprayed with selenite.In contrast to the root,Se content in stem and leaf of plants spraying with selenite ishigher.It seems that selenate hasa better mobility in SM than selenite.The Se content of SM plants can be effectively increased with spraying both kind of inorganic selenium aqueous solution.The selection of selenium reagent for Se supplement still depends on the results of speciation analysis of selenium.In order to understand the effect of selenium-enrich on the content of secondary metabolites in SM,the content of total tanshinone was determined by ultraviolet spectrophotometry,the content of total flavonoids was determined by NaNO₂-Al（NO₃）₃ colorimetric method and the total phenolic acid content was determined by Prussian blue method on condition that those effective conponents had been extracted by ethanol solution assisted by ultrasound.The results of variance analysis showed that the effect of selenium cultivation on the content of total tanshinone,total flavonoids and total phenolic acids in roots and leaves of SM was not enough to be manifested or exhibited or the trend is not significant due to the uncontrollable natural stress factors.In this field experiment,selenium application could not significantly increase the content of secondary metabolites in roots,stems and leaves of SM.Se-containing polysaccharide has higher physiological activity than polysaccharide,and Se-containing polysaccharide is the main binding forms of selenium.Therefore,the methods and conditions of extraction,isolation and purification of selenium polysaccharide are studied in this paper.The optimum extraction conditions were as follows: the ratio of material to liquid was 1: 32.42,the extraction time was 40.96 min,the ultrasonic power was 82.72% by single factor experiment and Box-Behnken center combination design experiment.At that condition,the extraction yield of polysaccharide was 14.09%.The polysaccharide of SM was isolated and purified by DEAE-52 cellulose column.The control group、Se（Ⅳ）and Se（Ⅵ）high dose group of SM were subjected to gradient elution with distilled water and different concentrations of NaCl solution.The polysaccharides of six different polarities were obtained by IR.The control group does not contain selenium,and leaf sprayed with sodium selenite and sodium selenate aqueous solution of selenium-rich SM,the selenium and polysaccharides were connected by（?）,the selenium did not change the main structure of polysaccharides,but only in the polysaccharide side chain in the form of glycosides and sugar esters connected.