Utilization of corncob xylan as a sole carbon source for the biosynthesis of endo-1,4-β xylanase from Aspergillus niger KIBGE-IB36

Abstract

Background: Xylan is a hemicellulose polysaccharide which is composed of β-1,4-linked d-xylosyl residues. Endo-1,4-β xylanase has the ability to cleave xylan back bone chains to release xylose residues. They are produced by a number of prokaryotic and eukaryotic organisms. Among them, filamentous fungi are attracting great attention due to high secretion of xylanolytic enzymes. Endo-1,4-β xylanase has wide industrial applications such as in animal feed, bread making, food and beverages, textile, bleaching of wood pulp, and biofuel production. Results: In this study, different Aspergillus species were screened for the production of endo-1,4-β xylanase, and Aspergillus niger KIBGE-IB36 was selected for optimum production of enzyme in submerged fermentation technique. Influence of various fermentation conditions was investigated to produce high titer of endo-1,4-β xylanase. The results indicated that A. niger KIBGE-IB36 showed optimum production of endo-1,4-β xylanase at 30 °C, pH 8 after 6 days of incubation. Different macro- and micronutrients were also amalgamated in the fermentation medium to increase the enzyme production. The parametric optimization of endo-1,4-β xylanase resulted in tenfold increase after hydrolysis of 20 g L−1 corncob xylan. Conclusions: The use of low-cost substrate approach for high production of endo-1,4-β xylanase has been developed successfully that can be consumed in different industrial applications especially in paper and pulp industry.[Figure not available: see fulltext.].