Research On Foshou Yam Active Ingredients And Its Nutrient Instant Rice Development

The many-years creeping herb Dioscorea opposite’s root which people commonlyknown as yam is not only the essential ingredient of Chinese traditional medicine whichhas excellent medical health efficacy, but also vegetables which has the flavor quality ofwaxy delicious. This study taked Foshou yam which comes from Hubei Wu Xue as rawmaterial, and carried on the research of its main active ingredients，firstly.Yam crude polysaccharide extraction conditions were optimized by single factor andorthogonal experiments, the best yam crude polysaccharide extraction conditions in thelaboratory were determined. Yam-water ratio is1:20, temperature is60℃, time is3h,extractive times is2, after merger the extracted enrichment liquid, add anhydrous ethanoltill the ethanol concentration reach to80%and precipitate10h, the yield to yam crudepolysaccharide is5.81%.Through deproteinization and decolorization，yam crude polysaccharide turned intoyam polysaccharide.Using DEAE-Cellulose52column chromatography，two kinds of yampolysaccharide were separated， which are the neutral and acidic polysaccharidecomponents, named YPn and YPa respectively. The neutral polysaccharide was usedSephadex G-100gel column chromatography to isolate two neutral polysaccharidecomponents: YPn-I and YPn-II, the acidic polysaccharide was used Sephadex G-100gelcolumn chromatography proved to be a pure polysaccharide YPa of uniform molecularweight. Ultraviolet spectrum analysis shows that three types of polysaccharide are notcontains proteins, nucleic acids and polypeptides, and infrared spectrum scanning provesthat three kinds of polysaccharide have the characteristic absorption peak ofpolysaccharide. TLC analysis of the monosaccharide composition of three kinds ofpolysaccharide shows that the neutral polysaccharide YPn-I’s monosaccharide compositionis arabinose, fructose and glucose. The neutral polysaccharide YPn-II’s monosaccharidecomposition is fructose, mannose and glucose, the acidic polysaccharide YPa’smonosaccharide composition is xylose, galactose and glucose. With multi-angle laser lightscattering detector and refractive index detector, gel permeation chromatography determined molecular weight of yam polysaccharide, the yam neutral polysaccharidecomponents of YPn-I, YPn-II average molecular weights are65086and20982respectively.The yam acidic polysaccharide component YPa average molecular weight is34780.Secondly, other pharmacological active ingredients content in the Foshou yam weredetermined. Use the reversed phase high performance liquid chromatography (RP-HPLC)determination the allantoin content in Foshou yam and spectrophotometry at544nm,765nm and510nm wavelength determination of saponins, total polyphenols and flavonoidscontents, respectively.Results showed that content of allantoin is0.483±0.021(%); contentof dioscin is0.099±0.004(%); content of polyphenol is1.040±0.069(mg/g); content offlavone is10.843±0.099(mg/g).Finally, the compatibility of Foshou yam, medlar, tuckahoe and the japonica ricepowder by twin-screw extruding nutrient instant rice was studied. Tested the physical andchemical indicators, starch viscosity, rehydration, degree of gelatinization and activepolysaccharide content. By hot-water soaking and stewing, two way to get the rice cooked,steamed rice has bigger hardness, viscosity and balance degree, and the soaked rice hashigher elasticity. Extruded nutrient instant rice after absorbing water is more sticky thanconventional rice, its average recovery time is8.2min, the average recovery rate is166%,the gelatinization degree is88.267±0.347(%), the polysaccharide content is4.324±0.021(mg/g).