Lipase-catalyzed synthesis of 4-methoxy cinnamoyl glycerol

Cinnamoyl esters are used as organic ultraviolet (UV) filters in sunscreens and cosmetic formulations. To avoid any possible harmful effects from chemically synthesized product, the enzymatic synthesis appears to be an excellent way to satisfy the present consumer demand for natural products. Enzymatic esterification of 4-methoxy cinnamic acid (4MCA) with glycerol was carried out in organic solvents using immobilized lipase B from Candida antarctica, in which the maximum conversion of 34% was found in isooctane at 70 °C after 24 h with 12% of enantiomeric excess. If the reaction continued for longer times (48 h) it leads to the formation of 16% of diester along with 56% of monoester. The results of enzymatic esterification were compared with reported chemical esterification and the present method was found to be superior in terms of conversion yields and priority to the formation of monoester. Synthesized monoester product was isolated and characterized by spectroscopic techniques.

Graphical abstract. Cinnamoyl esters are used as organic ultraviolet (UV) filters in sunscreens and cosmetic formulations. To avoid any possible harmful effects from chemically synthesized product, enzymatic esterification of 4-methoxy cinnamic acid (4MCA) with glycerol was carried out in organic solvents using immobilized lipase B from Candida antarctica.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Lipase-catalyzed synthesis of 4-methoxy cinnamoyl glycerol in organic solvents. ► Enzymatic esterification found to be superior in terms of conversion yields and priority to the formation of monoester. ► Reaction continued for longer times leads to the formation of diester.