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Xylanase produced by solid-state fermentation with Aspergillus niger ATCC 16404 as the raw material to the Yuba using DNS determination of enzyme activity , research the best enzyme production medium ratio , optimizing the optimum conditions for enzyme production . Single factor test results show that the the optimum medium : ammonium sulfate as a nitrogen source , mineral elements add magnesium sulfate , the add both 2 % ( w / w the Yuba dry weight ) , Yuba particle size of 25 ~ 50 mesh, an external carbon source , without surfactant . Select the solid-liquid ratio , initial pH, incubation time , then weight-optimized conditions for enzyme production by orthogonal test and verification test to get the best conditions for enzyme production : initial pH5.5 liquid ratio 1.00:1 (v / w) , incubation time 3 D , the concentration of 1.0 × 107/ml spore suspension was inoculated 0.3 mL/10 g, the enzyme activity in this condition for 366.29U / g . Yuba extracted dietary fiber as raw material , the study of alkali concentration , liquid to solid ratio , extraction temperature , extraction time hemicellulose extraction rate . Hemicellulose extraction conditions optimized by single factor experiment and response surface design to determine the best : liquid ratio 16.42:1 , extraction time 7.65 h , lye concentration of 4.28% , extraction temperature 45 ° C. Under these conditions of semi- the cellulose extraction rate of 4.55% . Yuba extracted hemicellulose xylan enzymatic hydrolyzate as raw materials , the use of activated carbon bleaching investigated decolorization time , pH , and activated carbon added amount and bleaching temperature the impact on the the decolorizing rate and sugar retention rate . Selected on the basis of single - factor test pH, activated carbon addition and the bleaching temperature as independent variables , using software the Design-expert7.1.2 response surface design and analysis , and on the decolorization time 50 min , rotation speed 150r/min foundation , the best sugar retention conditions were as follows : pH 3.85 , activated carbon was 1% , bleaching temperature of 30 ° C , the decoloration rate on this basis , and sugar retention of 96.91% and 96.52% , respectively . Oligosaccharides liquid activated carbon decolorization ultrafiltration treatment , and then study the static of desalination and dynamic desalination and resin regeneration cation resin 001 × 7 anion resin 201 × 7 in series of oligosaccharides solution desalination by ion chromatography poly sugar oligosaccharide content of 88.35% .
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