초록
High level production of an extracellular cellulase-poor alkali stable xylanase has been conceded from newly isolated Bacillus pumilus SV-85S under solid state fermentation using wheat bran as a substrate. Optimization of the fermentation conditions enhanced the enzyme production to 73,000+/-1000IU/g dry substrate, which was 13.8-fold higher than unoptimized conditions (5300IU/g). The enzyme titre was highest after 48h of incubation at 30<SUP>o</SUP>C with 1:3 ratios of substrate to moistening agent using wheat bran as a carbon source. The enzyme could be produced in significant levels by using either tap water or distilled water alone as a moistening agent. An elevated production of xylanase by B. pumilus SV-85S in the presence of wheat bran, a cheap and easily available agro-residue, in shorter duration would apparently reduce the enzyme cost substantially. The enzyme was completely stable over a broad pH (5-11) range and retained 52% of its activity at a temperature of 70<SUP>o</SUP>C for 30min. The desired characteristics of this enzyme together with economic production would be important for its application in paper and pulp industry.