Screening of a thermostable neutral cellulase-secreting bacteria and optimization of fermentation conditions

The strain D-9 of bacteria producing cellulase was isolated from soil samples,and its cellulase had high stability activity.The production technology of cellulose by liquid fermentation was studied with D-9 as experimental materials.After incubation for 72h,the cellulase of shaking culture of D-9 was 24.23IU/mL with a most proper temperature of 70℃ and a most proper pH of 6.0.This enzymatic properties were rather applicable to the textile industry.Based on the analysis of morphology and some biochemical and physiological characteristics,strain D-9 was identified as Paenibacillus elgii.In addition,the experiment carried on a one-way analysis of the carbon source,nitrogen source and pH of fermentation medium.