Exptl. data on the temp. relationship of lipases from Rhizopus oryzae 3562 and Enterobacter aerogenes activity published by Kumari et al. (2008), were used to calc. the optimum temp., activation energies and deactivation energies of the p-nitrophenyl palmitate hydrolysis according a resp. math. model of the reaction. The calcd. values were 298.02 +/- 3.02 K, 32.86 +/- 14.86 kJ/mol and 59.74 +/- 8.72 kJ/mol for lipase from R. oryzae 3562 and 295.00 +/- 2.74 K, 45.37 +/- 16.28 kJ/mol and 59.28 +/- 14.07 kJ/mol for lipase from E. aerogenes.