Screening Of Xylanase Producing Bacteria Strains From Bovine Rumen And Research Of Theenzyme Properties

Xylan is an abundant renewable resource in the world.The effective utilization of xylan can reduce stress for global resources.The procedure of xylan degrading is catalyzed by xylanase which is produced by microorganism.Bovine ruman could degrade xylan efficiently.Its interior contains a lot of xylan degeadation bacterium.In this study I made birchwood xylan as the solo carbon source to screen bacteria for xylanase production and got four stains of bacteria.The activity of xylanases were determined.Study the strain BF which has the highest enzyme activity in these four stains.The research content is as follows:(1) I screened 4 strains which could degrede xylan. Then the strain with the highest activity of xylanase was identificated through 16 Sr DNA, physiological and biochemical identification.The strain was confirmed as paenibacillus and named BF.(2) To optimize the fermentation conditions of paenibacillus BF, it was culture on basic fermentation culture medium at constant temperature shaker with different nitrogen source, carbon source and content of inorganic salts.Found the optimum medium are: birchwood xylan 0.6%,Na2HPO4 0.4%,(NH4) 2SO4 0.02%,CO(NH2) 2 0.05%,Mg SO4.?7H2O 0.05%,Ca Cl2 0.05%.(3) Determination enzymatic properties of xylanase: the optimal p H of xylanase was 6.0 and optimal temperature was 60℃. It could retained 65% relative activity after incubating 180 min at 60℃.