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Washing cellulase imbalance has the characteristics of the of high Cx activity , low FPA activity , used in textile finishing , cotton knitted fabric surface can partially hydrolyzed . Treatment appropriate after finishing knitted fabric can fine look and feel of the fabric is smooth and soft , wear comfortable clothing , natural, and has the advantage of less pollution . China 's washing cellulase there are still enzyme production and enzyme activity , and optimization of fermentation conditions is not clear , it is difficult to achieve large-scale production , a repeat of the washing effect and poor . Therefore, the breeding of high-yield strains , to explore the fermentation conditions , cellulase production characteristics of the study and master , has a very important significance . In this paper, a high Cx / FPA enzyme producing bacteria strains M , a high-yield strains of M - 18 through a variety of mutagenesis breeding , Cx enzyme activity increased by 2.56 times, up to 398.00U/ml , and its FPA enzyme activity increased much. Fermentation to optimize test to determine the suitable carbon and nitrogen sources and fermentation conditions : as the carbon source , sweet sorghum residue of 2% to 0.2% NaNO 3 as the nitrogen source , the remaining 0.3% peptone , yeast extract 0.05 % , the K 2 < / sub > in HPO 4 0.4% , the CaCl 2 < / sub > 0.03 % , the MgSO 4 < / sub > 0.03 % CMC-Na 1%, 50 ml / bottled liquid , 30 ° C , to 180r/min shake flask cultures 5d . After optimization Cx specific activity than before to improve 90.55U/ml . Intermittent feeding fed-batch experiments show that : in the fermentation process mid-stream of the M-18 and nitrogen source ( peptone 1 % , 1.0 ml / bottle veal infusion cream 1 % , 0.6 ml / bottle ) ; , KH2PO4 1 % , 1.0 ml / bottle ; CMC the - Na0.5 % , 1.0 ml / bottle can further improve the level of enzyme production of the M-18 , the Cx enzyme activity increased 78.95U/ml . Study M - 18 Cx action of the enzyme conditions , the results showed that the optimum conditions for enzymatic reactions : a temperature of 50 ° C , pH 4.6 . When the substrate concentration is much greater than the concentration of enzyme , the enzymatic reaction rate is proportional to the concentration of substrate and enzyme concentration should be chosen to different performance requirements . Denim finishing , processing time more than 30min . Add a small amount of enzymatic reaction the Zn 2 < / sup > , the Fe 2 , Cu 2 promoted . Cx enzymes were isolated and purified , pure Cx enzyme , molecular weight of 56.85 KD . M-18 strain fermentation broth processing denim, allows the soft, cloth-like smooth surface. The strains in textile finishing , there will be a certain application prospects .
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