Partial purification and properties of cellulase-free alkaline xylanase produced by Rhizopus stolonifer in solid-state fermentation

rhizopus stolonifer was cultivated in wheat bran to produce a cellulase-free alkaline xylanase. the purified enzyme obtained after molecular exclusion chromatography in sephacryl s-200 hr showed optimum temperature as 45o c and hydrolysis phs optima as ph 6.0 and 9.0. xylanase presented higher vmax at ph 9.0 (0.87 μmol/mg protein) than at ph 6.0 and minor km at ph 6.0 (7.42 mg/ml) than at ph 9.0.