Enzymatic synthesis of AHA derivatives for cosmetic application

An immobilized lipase from Candida antarctica (Novozym 435) was used to catalyze synthesis of alpha-butylglucoside lactate by transesterification between alpha-butylglucoside and butyllactate in a solvent free medium. The influence of the reaction pressure on yield was investigated. The elimination of butanol co-product under reduced pressure resulted in the shift of the reaction equilibrium position in favor of synthesis. More than 95% of 0.5 M alpha-butylglucoside was converted in only 30 h. Consequently, very high alpha-butylglucoside lactate concentration (170 g/l) was obtained in a single batch reaction. Moreover, one purification step was enough to obtain alpha-butylglucoside lactate with a purity above 95% (w/w). Properties of alpha-butylglucoside lactate have been evaluated. This derivative is far less harmful than free lactic acid: a 0.55 M aqueous preparation is far less irritant than a lactic acid solution of a similar concentration. (C) 1998 Elsevier Science B.V. All rights reserved.