In contrast to the results reported by Hendy et al.(1984) for fed-batch cultivation,in the present work no proportionality was observed between the amount of substrate delivered to the system and the maximum enzyme concentration obtained. In the earlier work, a proportional increase in FPase activity was observed with increased addition of Solka Floc Maximum FPase activities of 10,20 and 30 FPU mL were obtained for 50,100 and 150 gL of cellulose respectively