Study On The Characteristics Of Microorganisms Producing Cellulase Derived From Rumen

A cellulase-producing strain T15 isolated from the rumen content flora of goats was studied.In this experiment,strain T15 was identified from three aspects:physiology,biochemistry,morphology and molecular biology.The enzymatic properties of strain T15 and cellulase were also studied.T15 was identified as Bacillus amyloliquefaciens by strain identification.Cellulase activity was determined by DNS method.And optimizing the composition of strain T15medium,it was found that the optimum carbon and nitrogen sources were 6 g/L of glucose and 5 g/L of beef extract.Adding a certain amount of Ca²⁺and Mg²⁺to the medium could promote the production of cellulase.When adding 0.03 mol/L Ca²⁺to the medium,the activity of strain T15 enzymes increased significantly and reached 21.06 U/mL.Based on the results of single factor optimization of strain T15 culture conditions,four factors and three levels orthogonal experiment of temperature,time,initial pH and inoculation quantity design were carried out to optimize the culture conditions.The optimal results were as follows:initial pH of culture medium was 7,culture temperature was 35?,inoculation quantity was 9%,culture time was 40 h,and enzyme activity reached 26.96 U/mL.The results of variance showed that the effects of culture time,inoculation amount,culture temperature and initial pH of culture medium on cellulase production increased in turn.Through the study of cellulase properties produced by strain T15,it was concluded that strain T15 was most suitable for cellulase enzymatic reaction of strain T15 with pH of 7 and temperature of 45?.Adding certain concentration of Ca²⁺,Mg²⁺in the reaction system could promote cellulase enzymatic reaction of strain T15.