SURFACTANT EFFECT ON ENHANCING (S)-NAPROXEN PRODRUG PRODUCTION FROM RACEMIC NAPROXEN BY LIPASE

In the enantioselective esterification of racemic naproxen with 4-(2-h ydroxyethyl) morpholine by Lipase MY in organic solvents, a productivi ty improvement of the desired (S)-naproxen ester from 0.42 to 0.72 mM at the reaction time of 130 h was observed, when the surfactant bis (2 -ethylhexyl) sodium sulfosuccinate (AOT) was added in the reaction mix ture. The presence of a small amount of exogenously added water dramat ically activated the enzyme in AOT/cyclohexane-reversed micelles. Deso rption of the surfactant molecule from the enzyme mass and solubilizat ion of the enzyme into reversed micelles were used to elucidate an exi sting maximum of the initial rate of (S)-naproxen synthesis with the w ater content. Moreover, the effects of alcohol and surfactant concentr ation on the enzyme activity are reported.