Study of interfering substances in a simple, new spectrophotometric assay for phenylalanine ammonia-lyase

A study of interfering substances in a new spectrophotometric assay for phenylalanine ammonia-lyase has been made. None of the commonly interfering compounds interfere in the assay to any significant extent. The assay has been employed for the partial purification of the enzyme from mint leaves (Mentha viridis'L).