Effect of agitation rate on the growth and production of xylanase free of cellulase by Thermomyces lanuginosus MH4 in bioreactor

Cellulase-free xylanase production by T. lanuginosus MH4 was investigated i n a 3-litre stirred tank bioreactor under different agitation rates and an aeration rate of 1 v/v/m. The cultivation time in the bioreactor was reduce d significantly over that in shake culture conditions. A xylanase productiv ity of 0.1 mkat l(-1) h(-1) was achieved on xylan in the bioreactor. This w as nearly double to that obtained in shake culture. The agitation rates inf luenced both growth and enzyme secretion in the bioreactor. The highest lev el of biomass concentration and activities of both xylanase and beta-xylosi dase were obtained at 150 rev min(-1).