Enzymatic acylglycerol synthesis in a membrane bioreactor

Abstract

Lipases can catalyze the esterification reaction in a two‐phase system. TheCandida rugosa lipase‐catalyzed esterification of decanoic acid with glycerol is described in this work for an emulsion system and for a hydrophilic membrane bioreactor. The enzymatic activity is studied in relation to the interface area between the two phases, the enzyme load and the reactor volume. The initial rate per unit interface area, the interfacial activity, is roughly equal for both systems indicating that the cellulose membrane does not hinder the esterification. Because the interfacial activities are equal, the volumetric activity of a membrane system is only specific area related, so a hollow fiber membrane device is preferable. The activity is also a function of the enzyme load. The optimum load in a hydrophilic membrane reactor is one to three times the amount of a monolayer, while in an emulsion system several times this amount. This could indicate that in the emulsion system the adsorption is in a dynamic state while at the membrane surface the adsorption reached its equilibrium state.