Enhancement of activity of sol-gel immobilized lipase in organic media by pretreatment with substrate analogues

By performing pretreatment with substrate analogues, an activation of lipase immobilized into organic-inorganic hybrid silicate was attempted in esterification of menthol with butyric acid in organic media. With decreasing water content of immobilized lipase preparations, the activity of immobilized lipases by (-)-menthol pretreatment was enhanced, and the highest activity was obtained at water activity, a(W) = 0.11. However, the pretreatment of immobilized lipases with (-)-menthol could not improve the enantioselectivity. In addition, the activity of pretreated immobilized lipases increased with increasing the chain length of alcohol as a substrate analogue. Consequently, it was found that hydrophobic and bulky alcohol was an effective substrate analogue to activate immobilized lipases. (C) 2001 Elsevier Science BY. All rights reserved.