Enhanced production of xylanase by Fusarium sp. BVKT R2 and evaluation of its biomass saccharification efficiency.

Abstract

Growth of Fusarium sp. BVKT R2, a potential isolate of forest soils of Eastern Ghats on birchwood xylan in mineral salts medium (MSM) under un-optimized conditions of 30°C, pH of 5.0, 150rpm and inoculum size of 5 agar plugs for 7days, yielded titer of 1290U/mL of xylanase (EC 3.2.1.8). The effect of various operating parameters such as different substrates and their concentration, additional carbon and nitrogen sources, incubation temperature, initial pH, agitation and inoculum size on the production of xylanase by Fusarium sp. BVKT R2 was studied in shake flask culture by one factor at a time approach. The same culture exhibited higher production of xylanase (4200U/mL) when grown on birch wood xylan in MSM under optimized conditions with an additional carbon source-sorbitol (1.5%) nitrogen source-yeast extract (1.5%) temperature of 30°C, pH of 5.0, agitation of 200rpm and inoculum of 6 agar plugs for only 5days. There was enhancement in xylanase production under optimized conditions by 3.2 folds over yields under un-optimized conditions. Growth of BVKT R2 culture on locally available lignocelluloses-sawdust, rice straw and cotton stalk-in MSM for 5days released soluble sugars to the maximum extent of 52.76% with respect to sawdust indicating its greater importance in saccharification essential for biotechnological applications.