Optimal pH for the secreted endoglucanase activities. The culture supernatants from fungi grown on microcrystalline cellulose were brought to the pH indicated and the endoglucanase activity was measured. Activities are given as percent of the maximal measured endoglucanase activity. The experiment was repeated three times. The activities were determined as described in “Methods”. Error bars indicate standard deviations. See Table 1 for abbreviations of fungal names. Stars next to bars indicates that the activity at this pH was significantly lower than the highest activity (P < 0.05, Student’s T-test).