STUDY ON THE PRODUCTION OF A XYLANOLYTIC COMPLEX FROM PENICILLIUM-CANESCENS 10-10C

We screened about a hundred microorganisms (including unidentified yea sts, fungi, and bacteria) for their ability to produce xylanolytic enz ymes. About 40 of them were hemicellulolytic; among these, we selected Penicillium canescens 10-10c for detailed study because of its abilit y to produce an interesting enzymatic complex in quantity. The xylanas e complex was cellulase-free, and had an optimal activity at pH 4.6-5. 0 and 55-60 degrees C on birchwood xylan. The best production was on s oya meal and wheat straw; expression of the xylanase was repressed by glucose, xylose, and lactose. The optimization of culture medium and m ode (fed-batch) enabled us to improve the production three to four tim es. The importance of the mixing conditions on the biomass and xylanas e production is also reported.