Screening of commercial enzymes for the enantioselective hydrolysis of R,S-naproxen ester

• Published in: Enzyme and microbial technology Vol. 32; no. 3; pp. 472 - 477
• Main Authors: Steenkamp, Lucia, Brady, Dean
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.03.2003; Elsevier Science
• Subjects: Bioconversions. Hemisynthesis; Biological and medical sciences; Biotechnology; Enantioselectivity; Enzymes; Esterase; Fundamental and applied biological sciences. Psychology; Hydrolysis; Lipase; Methods. Procedures. Technologies; Naproxen; Hydrolysis; Enzymes; Enantioselectivity; Esterase; Lipase; Naproxen; Drug; Separation; Enzyme; Triacylglycerol lipase; Esterases; Carboxylic ester hydrolases; Screening; Ester; Enantiomer; Hydrolases
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/S0141-0229(02)00335-6

This study focused on the identification of suitable lipase or esterase activity for enantiomeric resolution of ( R,S)-naproxen. For an economically viable reaction the enantiomeric ratio ( E) should preferably be >100, while maximising the conversion will reduce the mass of material that requires racemisation and recycling. Hence the aim was to find an enzyme that yields ( S)-naproxen with an enantiomeric excess of more than 98%, a substrate conversion in excess of 40% of the racemate, and an E of >100. ( R,S)-Naproxen ethyl ester (NEE) (50 mg) was used as substrate for enzyme hydrolysis reactions at 37 °C for 4 h. Biocatalyst screening was performed in buffered aqueous solvent on a 1 ml scale. The reactions were stopped with 2 ml MeCN, filtered through cotton wool and analysed by HPLC to determine the percentage m/m and R/ S ratio. Eight commercially available enzymes were selected for optimisation of enantioselectivity through statistically designed experiments where the reaction conditions were varied. ChiroCLEC-CR from Altus and ESL001-01 from Diversa provided acceptable enantiomeric excess, but only ChiroCLEC-CR met the specification set for the enantiomeric ratio ( E).