Solvent‐free enzymatic synthesis of fatty alkanolamides

An environmentally benign and volume efficient process for enzymatic production of alkanolamides is described. Immobilized Candida antarctica lipase B, Novozym®435, was used to catalyze the condensation of lauric acid with monoethanolamine. The reaction temperature of 90°C was required to keep the reactants in a liquid state. Stepwise addition of the amine minimized problems caused by the formation of a highly viscous amine/fatty acid ion‐pair. The enzyme was both very active and stable under the reaction conditions, with about half of the activity remaining after 2 weeks. The maximum amide yield obtained when using equimolar amounts of the reactants was 75%, which could be increased to 95% upon water removal. Special precautions to avoid co‐distillation of the amine were required. Two different strategies to avoid the amine loss are presented. Biotechnol. Bioeng. 2007;97: 447–453. © 2006 Wiley Periodicals, Inc.