The Isolation And Identification Of Cellulase Production Strain And It’s Primary Application In The Enzymatic Deinking

Cellulose is the most abundant, and the most widely used macromolecularorganic substances on the earth, it is also an important renewable resources andenergy sources. The present state of cellulose in the nature is very special, whichdirectly led that such a difficult thing to the rational utilization of the valuableresources. A large number of studies have indicated that the biodegradation whichcompare to other cellulolytic method has a large advantage. To make the cellulosebroken down into small molecules or other nutrients, screening and isolating theexcellent bacteria which can rapid degradation or convert cellulose is very importantnow.In this study, Guangdong Shaoguan Zhuji Paper mill’s19soil and water samples,Guangdong Kaiping4hot spring water samples and3soil samples around the spas asthe screening sample, named the strain according to the time and place, screeningbased on the ratio of transparent hydrolytic ring diameter and the size of the colonydiameter which expressed by the Congo red method and plate culture stained, select9strains which have bigger ratio to the following screening step,7of them showedCMC-Na activity, we discuss the enzyme optimum reaction pH and reactiontemperature produced by these7strains, most of the enzymes in the range of pH6-7showed a relatively high cellulase activity, and we also found that related to otherstrains, C-SZ4-9produced the highest cellulase activity at60℃, while cellulaseproduced by CPC11has it’s maximum relative activity at70℃. Reaction conditionsof the cellulase produced by CRJB1is similar to the cellulase produced by C-SZ4-9,but their enzyme activity is different. Therefore, we select them to the follwingexperiments.CRJB1, C-SZ4-9, CPC11three bacteria is identified combined by the morphological,physiological and biochemical identification and molecular biological identificationmethod, finally species:1) C-SZ4-9at2) CPC113) CRJB1was classificated asBacillus tequilensis,Bacillus methylotrophicus and the Bacillus sp respectively. At thesame time, the growth curves of these three strains and enzyme activity-time curve was measured, The results showed that both of these three strains achieve it’s optimalenzyme activity within20h, and then, set the optimal reaction pH of each enzymeand the optimum reaction temperature as the intersection, the alkali resistance andheat resistance of the enzyme was measured. We found that, to a certain extent,enzymes under alkaline conditions is condutive to the resistance of the enzyme, whileto the enzyme, lower Enzymes activity and higher optimum reaction temperature hada better heat resistance.Finally, the cellulase produced by C-SZ4-9at CPC11, CRJB1three strains wasused as Enzymatic Deinking which add amount is0.5U/g dry pulp, the brightness ofthe result improved4.2%ISO,2.9%ISO,0.8%ISO respectively, the best:C-SZ4-9was picked to explore the added amount of enzyme in its enzymatic deinking, foundthat the amount of0.5U/g dry pulp Add can get the optimal brightness, This datacontrast with lipase ARL、 xylanase cs7and chemical deinking optimum deinkingeffect, the results show that the cellulase has a better brightness and lower ERIC.Compare with the chemical deinking, it comes out that with a little difference.