A new route to the direct synthesis of L-β-aryl-α-alanine (2) was established by using the red yeast (Rhodotorula rubra, Rhodotorula glutinis) cells containing L-phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) activity to catalyze the addition of ammonia to olefinic bond in trans-β-arylacrylic acid (1). Seven of L-α-amino acid 2 were prepared with the following yields: L-o-nitrophenylalanine (2a, 27.3%), L-m-nitrophenylalanine (2b, 10.2%), L-o-chlorophenylalanine (2c, 68.2%), L-m-chlorophenylalanine (2d, 42.1%), L-m-methylphenylalanine (2e, 49.1%), L-m-aminophenylalanine (2g, 7.9%) and L-4-pyridylalanine (2h, 7.9%), They were all confirmed as L-isomers owing to the positive Cotton effects of their circular dichroism near 215nm. The specific optical rotations of products 2c, 2d and 2e were also comparable to those inliterature. The enantiomeric excess (e. e) value were determined to be no less than 95% on a L-4-hydroxyproline-bonded high-performance ligand exchange column.

Key words: INFRARED SPECTROPHOTOMETRY, NMR SPECTROMETRY, AMMONIA, ACRYLIC ACID P, MICROBIAL TRANSFORMATION, ALANINE P, RHODOTORULA