Carica papaya lipase (CPL) stores in the crude papain is explored as a high enantioselective biocatalyst for the hydrolysis resolution of (R,S)-naproxen 2,2,2-trifluoroethyl ester in water-saturated solvents. An optimal temperature of 60 degreesC for obtaining the maximum initial rate for (S)-naproxen ester in isooctane is found, where the lipase possesses high enantioselectivity with E = 122. Less hydropholic solvents of cyclohexane and MTBE than isooctane are vital on decreasing the lipase activity and enantioselectivity. Comparisons of enzyme performances for CPL and lipase MY indicate that CPL is more enantioselective and active for (S)-naproxen ester, and also more stable in water-saturated isooctane at 60 degreesC. (C) 2004 Elsevier Inc. All rights reserved.