Response surface methodological study of esterification of lactic acid with palmitic acid catalyzed by immobilized lipases from Mucor miehei and porcine pancreas

<p align="justify">Response surface methodology was employed
to analyze the effects of important process parameters
such as lactic acid/palmitic acid (LA/PA) concentrations
(Xs), enzyme/substrate (E/S) ratios (Xe) and incubation time (Xt) on the preparation of palmitoyl lactic acid using Mucor miehei lipase (MML) and porcine pancreas lipase (PPL). Experimental ester yields were found to be in good agreement with predictions. In the case of MML, the ester yield was found to increase with Xe and Xt and a maximum yield of 27 mM was obtained at Xe = 128 activity units(AU)/mM of substrate, Xs = 64±74 mM and Xt = 72 h. In the case of PPL, the ester yield was found to increase with increases in Xe and Xs. Optimum conditions for PPL were Xe = 45 AU/mM,Xs = 85±90 mM and Xt = 72 h, at which the maximum
ester yield of 15 mM was obtained.</p>