Study on the enzymatic hydrolysis of racemic methyl ibuprofen ester

The hydrolysis of racemic methyl ibuprofen ester in the presence of lipase from Candida rugosa was investigated in shake flasks. Experiments were perf ormed to study the effect of temperature, pH and shaking speed on the react ion rate. Different hydrophobic co-solvents were screened for the highest r eaction rate and the presence of enzyme inhibition by substrate and product s was examined. A kinetic expression was then proposed to describe the reac tion. Kinetic parameters were determined for the optimum operating conditio ns and the proposed model was verified with the experimental results. Next, this reaction was scaled up to a fed batch stirred tank reactor. Batch rea ctor and fed batch reactor configurations were compared for better conversi ons. The effects of aqueous phase hold-up, substrate concentration and feed flow rate on the conversion of the reaction were also studied. Higher conv ersions were obtained in a fed batch reactor when compared with the batch r eactor. In the fed batch reactor, increased conversions were observed with lower feed flowrates and high aqueous phase hold-up. (C) 2001 Society of Ch emical Industry.