Microbial oxidation of amines:: A preliminary investigation on the resolution of racemic 1-phenylethyl amine

The microorganisms Pichia pastoris, Pichia membranae-faciens, Candida boidinii and Aureobasidium sp. were screened for their ability to use amine as a nitrogen source. The range of amines accepted varied from organism to organism. P. pastoris used alpha-unsubstituted amines, while the other three strains used transformed a-substituted amines like cyclohexyl, 2-butyl and 1-phenylethyl amines. Biotransformation occurred via an oxidative pathway leading mainly to the production of the corresponding ketones. Investigation of the kinetic resolution of racemic 1-phenylethyl amine showed that the optically pure (S) enantiomer was obtained with Aureobasidium sp. experiments, and that with P. membranaefaciens or C. boidinii, the (R) enantiomer could also be produced, but with lower stereoselectivity (52% < ee < 70%). This resolution process constitutes a new method for the production of optically active amines.