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CDP - choline is an important precursor of the metabolism of phospholipids , are widely used in the treatment of various cerebrovascular diseases . Breeding strains of Candida utilis yeast Candida utilis, the biotransformation CDP -choline , fermentation conditions and fermentation medium , discover the optimal conditions for the enzyme reaction system . The cycloheximide and TTC as a screening pressure injection application of UV and N Candida utilisYL Mutagenesis . The results showed that the mutant Candida utilis, YL - 2 - 24 of CDP -choline increased by 2.01 times compared with strains of Candida utilis, YL . Candida utilis YL-2-24 fermentation process has been optimized . Through the medium of single factor experiment and orthogonal experiment , and ultimately determine the optimum fermentation medium of sucrose 4% , peptone 1.0 % , the Nano 3 < / sub > 2.0 % , the K 2 HPO 4 0.5%, MgSO 4 · 7H 2 O 0.5%, KH 2 PO 4 < / sub > 0.1 % ; shake flask fermentation conditions were initial pH 5.5 , inoculum 10 % the liquid volume 25ml/250ml , temperature 32 ° C , culture time 24h , speed 230 r / min , biotransformation generated 18.63mg/gCDP- choline . candida utilis YL-2-24 cell transformation enzymatic reaction conditions CMP10mM phosphate concentration 300mm , choline 50 mM phosphate , Portuguese sugar 1000mm , 34 ° C , pH 7.4 , plus wet cell 600mg/ml reaction 10h, biotransformation generate CDP - choline was 28.63% , the conversion rate of 84.4% .
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