3.5. Influence of moisture content on phytase production by Penicillium purpurogenum GE1 The results in Fig. 4 showed that maximum enzyme productivity (69 ± 12.7 U/g ds) was observed at 66% moisture content. Linearity between moisture content and enzyme production was observed up to 66%, and thereafter, an increase in moisture level in the fermentation medium led to reduction in enzyme productivity. Gautam et al. 2002 reported that the lowest and the highest water contents, led to reduction in the decomposition rate of the total organic matter. 3.6. Influence of pH on phytase production by Penicillium purpurogenum GE1 Results showed that the shift of pH toward the alkaline side resulted in an increase in enzyme productivity. The maximum phytase production of 75 ± 2.8 U/g ds was achieved at pH 8.0, after that there was a gradual decrease in enzyme production (Fig. 5). Although phytase production in acidic medium from