Improving lipase activity in solvent-free media by interfacial activation-based molecular bioimprinting

Nine lipases of mammalian, fungal and bacterial origin and two different model reactions, direct esterification and transesterification (alcoholysis), have been used to probe the potential in solvent-free media of the recently reported strategy of interfacial activation-based molecular (bio)imprinting (IAMI) [Mingarro et al., Proc. Natl. Acad. Sci. USA, 92 (1995) 3308]. The results demonstrate that the imprinting treatment permits nonaqueous rate accelerations which are lipase-dependent and span in some cases up to higher than two orders of magnitude. For several lipases, the method allows conversion yields after short reaction times (in either of the model reactions assayed) which are remarkably higher than those obtained with either the corresponding powdered commercial sample, the pH-optimized control lipase or even the lipase 'protected' by conventional means such as the use of lyoprotectants (sugars, polyols) or inorganic salts. Therefore, IAMI is proposed as a straightforward, convenient approach to improve lipase performance in more practical solvent-free-based applications.