FUNGAL FORMATION OF RASPBERRY KETONE DIFFERS FROM THE PATHWAY IN PLANT CELL CULTURE

Abstract

Various precursor substances for the biosynthesis of raspberry ketone were applied to the white rot fungus N. niveo-tomentosa to enhance product yields. L-Phenylalanine, phenyl pyruvate, phenyl propanoic acid, L-tyrosine, 4-hydroxyphenyl pyruvate, coumaric acid, 4-hydroxyphenyl propanoic acid, benzoic acid, hippuric acid, benzaldehyde, and 4-hydroxy benzaldehyde showed precursor activity, whilst cinnamic acid, phenyl acetic acid, phenyl acetaldehyde, and 4-hydroxybenzoic acid methyl ester inhibited fungal growth and/or formation of target compounds. Gas chromatography coupled with atomic emission detection (GC-AED) was used to elucidate the biosynthetic pathway to raspberry ketone after addition of 2H and 13C isotope labeled L-phenylalanine. Metabolic differences to the biosynthesis proposed for raspberry fruit became evident.