Aspergillus fumigatus produced more protein (114 mg/ml vs 51 mg/ml) and a higher specific activity of the
endoglucanase (9158 vs 6294) in the culture filtrates from solid state fermentation (SSF) than that from
submerged fermentation (SmF) when grown on wheat straw. The activation energy (Ea) of substrate
hydrolysis was less (33 kJ mol1) for the endoglucanase produced under the SSF (SSF-EG) than the
enzyme produced under the SmF (SmF-EG), which was 51 kJ mol1. The SSF-EG was more thermostable
as compared to the SmF-EG, evidenced by the larger enthalpy of activation of denaturation, DHD,
152 kJ mol1 vs 112 kJ mol1 at 50 8C (similar results at higher temperatures). It was further evidenced
by a steeper decline in the half lives (T1/2) of the SmF-EG than the SSF-EG. The free energy changes of
activation of denaturation of the enzymes, DGD, were 107 kJ mol1 and 106 kJ mol1 for the SSF-EG and
the SmF-EG, respectively, at 50 8C (similar results at higher temperatures). The entropies of activation of
denaturation, DSD, were positive for both of the enzymes. The melting temperature (Tm) of the enzyme
was 5 8C more for the SSF-EG than the SmF-EG. 2009