Production of Sporotrichum thermophile xylanase by solid state fermentation utilizing deoiled Jatropha curcas seed cake and its application in xylooligosachharide synthesis

• Utilization of deoiled Jatropha seed cake for Sporotrichum thermophile xylanase.
• Production of S. thermophile xylanase in high titre (1025 U/g dry seed cake).
• S. thermophile endoxylanase is effective for xylooligosachharide (XOS) production.
• Xylotetraose rich XOS produced are desirable in prebiotic applications.

De-oiled Jatropha curcas seed cake, a plentiful by-product of biodiesel industry was used as substrate for the production of a useful xylanase from Sporotrichum thermophile in solid state fermentation. Under the optimized conditions, 1025 U xylanase/g (deoiled seed cake) was produced. The xylanase exhibited half life of 4 h at 45 °C and 71.44 min at 50 °C respectively. It was stable in a broad pH range of 7.0–11.0. Km and Vmax were 12.54 mg/ml and 454.5 U/ml/min respectively. S. thermophile xylanase is an endoxylanase free of exoxylanase activity, hence advantageous for xylan hydrolysis to produce xylooligosachharides. Hydrolysis of oat spelt xylan by S. thermophile xylanase yielded 73% xylotetraose, 15.4% xylotriose and 10% xylobiose. The S. thermophile endoxylanase thus seem potentially useful in the food industries.