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Glucan is dehydration from glucose , polysaccharides, widely used in medicine, food and petroleum industries . Industrial dextran production is sucrose as substrate, Leuconostoc mesenteroides bacteria transformed bacteria biological biosynthesis . This study the intestinal membrane Leuconostoc 20074,21724 and 21725 of the culture conditions , the experimental results show that Leuconostoc mesenteroides bacteria growth of 21724 and 21725 in the same medium , considerable , both much better than the Leuconostoc mesenteroides bacteria 20074 . Leuconostoc mesenteroides bacteria 21724 best growing conditions for the initial sucrose concentration of 130g / L, initial pH 7.2 , culture temperature is 25 ℃, shaking speed 150r/min ; intestinal membrane Leuconostoc 21725 the best growth medium an initial pH of 7.0, and other conditions of the intestinal membrane Leuconostoc 21724 same . The three strains during fermentation studies show that Leuconostoc mesenteroides bacteria 21725 dextran highest yield obtained for transforming bacteria . In selected fermentation conditions , i.e. strains Enlarged culture 18h after access to the sucrose content of 15% inoculation amount of 10% of the fermentation medium, the medium initial PH value of 7.0, 25 ° C thermostat shaker 150r The / min cultured 24h, the the dextran yield of 88 % . The sucrose concentration in the liquid chromatography analysis of the fermentation broth test conditions : 80% acetonitrile as the mobile phase , mobile phase flow rate 1.0ml · min -1 , the injection volume was 20 μL , the column temperature was 30.0 ° C , the temperature of the detector 40.0 ℃. Intestinal membrane Leuconostoc bacteria 21725 for transforming bacteria , dextran fermentation process dynamics , cell growth kinetics equation is obtained , the product formation kinetic equation for CXCX
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