| Polysaccharides from Lentinus edodes for highly active anti-tumor and immune adjustment efficacy,is one of the most full research polysaccharides.The United States and Japan is in a leading position of its research work..Extraction is the basic,which has the direct impact on subsequent rasearch work. This study used Lentinus edodes for raw material and established a pretreatment method by using dynamic high-pressure microfluidization technology with control group. Take the extraction parameters and mechanism of control group are the key points. The yield of polysacchardes, physical and chemical properties, polysaccharide primary structure and oxidation resistance were also studied. Provides reference for this technology in the application of effective component extraction.The main research contents and the conclusions are listed as follows:1.On the basis of single factor experiment, selectd water to raw material, pretreatment pressure, extraction temperature as the three factors, which factor choose three levels,useing the response surface analysis to optimize the best extraction conditon of the test group.The water to raw material and pretreatment pressure as well as extraction temperature played extremely significant and significant role on the linear effect of response surface rsults respectively. Pretreatment pressure, water to raw material and extraction temperature played extremely significant and significant role on the surfac effect of response surface rsults respectively. The interaction between each factors are not significant. The optimum conditions were as follows: pretreatment pressure147.4 Mpa,l/65 ratio of water to raw material,82.5℃extraction temperature. Under these conditions the yield of polysaccharides was theoretical maximum of 7.234%,which was consistent with five validation experiments results. The content of polysaccharide was measured by phenol-sulfuric acid method.Under the same extraction time,extraction temperature and water to raw material, the dynamic high-pressure microfluidization(DHPM) extraction won the high rate of polysaccharides and better extract parameters.2.0n the basis of Hagen-Poiseuille law and Fick's first law of diffusion and combined with SEM images, mechanism of dynamic high-pressure microfluidization pretreatment were analyzed. Results showed that, the material subject to a series force in chamber such as instant pressure variation and strong shear force accelerated the solute infiltration and diffusion process, and damaged cell structure, reduced the mass transfer resistance, further enhanced permeability and diffusion effect. Therefore, as compared with control group, DHPM extraction is more likely to gain higher yield of polysaccharide.3.The effects of DHPM extraction on the physical and chemical properties of polysaccharides are as follows:DHPM extraction does not add new polysaccharide components, but caused polysaccharide particle size distribution uneven, apparent viscosity reduced, molecular weight drops, polysaccharide degradation into smaller molecules chain; UV spectral analysis showed that DHPM extraction polysaccharide is non-protein binding polysaccharide, Infrared, X-ray diffraction,1H NMR spcetra, and Congo red experiments showed that the DHPM extraction without damaging polysaccharide structure and polysaccharide solution conformation.4.The effects of DHPM extraction on the oxidation resistance of polysaccharides are as follows:compared with control group, because of DHPM extaction reduced the molecular weight of polysaccharide, getting better antioxidant capacity than the control group, and the effect of clearing hydroxyl radicals, superoxide radical, DPPH free radicals and NO2- in vitro, increased with the concentrate of polysaccharides increasing. |
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