INEXPENSIVE, RAPID PROCEDURE FOR BULK PURIFICATION OF CELLULASE-FREE BETA-1,4-D-XYLANASE OF HIGH SPECIFIC ACTIVITY

A process has been developed for the bulk purification of cellulase-free beta -1,4-D-xylanase from the fungus Trichoderma harzianum E58. The process involved the primary step of ultrafiltering the culture filtrate via a 10,000-molecular-weight cut-off membrane to separate the cellulase (retentate) and xylanase (permeate) fractions. The xylanase was concentrated and solvent exchanged by adsorption to a cationic exchanger, SP-ZetaPrep 250, followed by elution with a pH change in the buffer to give a purified and concentrated xylanase complex dissolved in a low-salt buffer. The process scheme was designed to facilitate scale-up to an industrial level of production.