Production, Partial Purification and Characterization of Extracelluar Xylanase from Chaetomium globosum

Culture conditions for efficient production of extracellular xylanase by fungus, Chaetomium globosum isolate Cg2, have been standardized. Further, xylanase has been partially purified and characterized. Xylanase activity was maximum after 9 days of incubation when amended in medium with 1.5 % xylan as carbon source and 0.6% NH₄H₂PO₄ as nitrogen source. Partial purification of the xylanase was accomplished by ammonium sulphate precipitation, followed by further purification by anion exchange chromatography on DEAE-Sephadex A-50 column. The partially purified enzyme was electrophoresed on SDS-PAGE and a single band produced corresponded to molecular weight, 32 kD. The optimum temperature and pH for maximum activity of purified xylanase were 30°C and 5.5, respectively. Both the purified xylanase and culture filtrate have shown the antifungal activity against Bipolaris sorokiniana, a causal organism of spot blotch of wheat. Purified xylanase at 100 μg ml^?1 concentration caused 100 per cent inhibition of conidia germination of B. sorokiniana, whereas the culture filtrate was able to inhibit germination up to 67.5 per cent.