Xylanases (E.C.3.2.1.8) are key enzymes, which play an important role in the breakdown of xylan. Wheat bran and corn cob are a rich source of xylan (28%) and xylose (23%). Therefore these are attractive substrates for production of xylanase & ßxylosidase enzyme. Xylan, a major component of hemicelluloses, is a heterogeneous polysaccharides consisting of ß-1, 4 linked to D-xylosyl residues on th...

BACKGROUND The filamentous fungus Trichoderma reesei is widely utilized in industry for cellulase production, but its xylanase activity must be improved to enhance the accessibility of lignocellulose to cellulases. Several transcription factors play important roles in this progress; however, nearly all the reported transcription factors typically target both cellulase and hemi-cellulase genes. ...

The Bacillus subtilis xylanase A was subjected to site-directed mutagenesis, aimed at changing the interaction with Triticum aestivum xylanase inhibitor, the only wheat endogenous proteinaceous xylanase inhibitor interacting with this xylanase. The published structure of Bacillus circulans XynA was used to target amino acids surrounding the active site cleft of B.subtilis XynA for mutation. Twe...

A new fungus Cladosporium oxysporum GQ-3 producing extracellular xylanase was isolated from decaying agricultural waste and identified based on the morphology and comparison of internal transcribed spacer (ITS) rDNA gene sequence. C. oxysporum produced maximum xylanase activity of 55.92 U/mL with wheat bran as a substrate and NH4Cl as a nitrogen source. Mg(2+) improved C. oxysporum xylanase pro...

Although several xylanases have been studied, only few xylanases from marine micro-organisms have been reported. We report here a novel halotolerant xylanase from marine bacterium Bacillus subtilis cho40 isolated from Chorao island of mandovi estuary Goa, India. Extracellular xylanase was produced by using agricultural residue such as wheat bran as carbon source under solid-state fermentation (...

Background The transition to a more environmentally friendly economy has prompted studies of modern biorefineries, including the utilization of low-value lignocellulose. The major challenge facing the widespread application of biorefineries is the high cost of enzymes that can efficiently hydrolyze recalcitrant cellulose to sugars. Penicillium oxalicum produces large amounts of plant-cell-wall-...

The most important building block of hemicelluloses is xylan. It is broken down into xylose oligomer residues by Xylanase an enzyme, produced by most organisms, to utilize xylose as primary source of carbon. The Xylanase produced are classified into families, viz 5, 8, 10, 11 and 43 of Glycoside Hydrolases (GH). Xylanase from family GH 11 are monospecific, they consist solely of Xylanase activi...

The xylanase gene from the ruminal bacterium Bacteroides ruminicola 23 is highly expressed in colonic Bacteroides species when carried on plasmid pVAL-RX. In order to stabilize xylanase expression in the absence of antibiotic selection, the xylanase gene was introduced into the chromosome of Bacteroides thetaiotaomicron 5482 by using suicide vector pVAL-7. Xylanase activity in the resulting str...

Xylanase treatment can be an environmentally friendly way to improve the formability and drainability of chemi-mechanical pulp (CMP). Improvements in xylanase treatment efficiency are possible with application of an ultrasonic wave via the cavitation effect. Results showed that the specific surface area (SSA) of the combined treated pulp increased by 14.6% at an ultrasonic treatment of 30 min a...