Production and partial characterization of endoxylanase by Bacillus pumilus using agro industrial residues

Abstract

Agro industrial residues, cheap sources of energy have high potential in the area of fermentation for the production of lignocellulases. Different agro industrial waste products were evaluated as substrates in submerged and solid-state fermentation for xylanolytic enzyme production by Bacillus pumilus and the enzyme titers were compared. Higher titer of endoxylanase was obtained with solid state than with liquid fermentation with feeble amount of cellulase. High proteolytic activity was observed in submerged fermentation where as in solid state the proteolytic activity was lower in all cases except in media supplemented with soy meal due to its high protein content. The endoxylanase produced by solid-state fermentation was stable over a wide range of pH and temperatures. The highest enzyme activity was obtained at pH 6.5-7 and at 50 degrees C. The enzyme could retain 30% of its activity even after 1 h at 60 degrees C. Considering the conditions under which Kraft pulps are bleached during the manufacture of paper, xylanase from B. pumilus exhibit favorable potential for application in the paper processing industries.