Cellulase Free Xylanase Production by Bacterial Isolate from Different Agro Residues

Abstract

newline Xylanases are now becoming one of the major industrial enzymes with vast application in the paper and pulp industries. The presnt study was made to isolate a potential xylanase producing microorganism and to explore a xylan rich residue for the production of xylanase and to make the process economically viable. newlineXylan, the major component of hemicellulose, requires the synergistic action of several hemicellulase enzymes for complete hydrolysis to monomer sugars. The principle enzyme in this process is endo-1,4-and#946;-xylanase, which cleaves the glycosidic bonds between xylosides, generating short xylooligosaccharides. The isolation of a suitable microorganism was carried out using standard plate assay, containing xylan as sole carbon source. Eighteen microorganisms were screened on the basis of growth and zone of hydrolysis. On further screening of the cultures screened, X3 was found to produce maximum xylanase with widest zone of lysis. Various xylan rich agro residues such as corn cob, rice husk, rice bran, sugarcane bagasse and wheat bran were tested for the enzyme production. Low cost wheat bran was selected as substrate under both submerged fermentation (SmF) and solid state fermentation (SSF). The isolated strain produced the maximum enzyme under SmF (12.5U/ml) in comparison to SSF(11.8U/g). It was identified as a novel strain of Bacillus licheniformis KJ842626 belonging to family Bacilllaceae. The bacterium isolated from the soil, produced cellulase free xylanase. Conventional fermentation methods were carried out and process parameters were optimized for the maximum enzyme production. newline newline