Rhodococcus AJ270 catalyzes the hydrolysis of ibuprofen amide and four related 2-phenylpropionamides to the corresponding acids in >94% yield. Complete hydrolysis of (R,S)-(+/-)-2-(4＇-isobutylphenyl)propionamide (ibuprofen amide) results in a racemic mixture of both ibuprofen enantiomers; however, the s-enantiomer of the amide is preferentially hydrolyzed initially so that partial hydrolysis yields s-(+)-ibuprofen, the biologically active enantiomer, in 90-94% enantiomeric excess. Hydrolysis occurs with conservation of configuration and >89.9% yield of s-(+/-)-ibuprofen.