IMPROVED TAXOL YIELD BY AROMATIC CARBOXYLIC-ACID AND AMINO-ACID FEEDING TO CELL-CULTURES OF TAXUS-CUSPIDATA

Cell culture of Taxus cuspidata represents an alternative to whole pla nt extraction as a source of taxol and related taxanes. Feeding phenyl alanine to callus cultures was previously shown to result in increased taxol yields, probably due to the involvement of this amino acid as a precursor for the N-benzoyl phenylisoserine side chain of taxol. In t his study, we have examined the effect of various concentrations of ph enylalanine, benzoic acid, N-benzoylglycine, serine, glycine, alanine, and 3-amino-3-phenyl-propionic acid on taxol accumulation in 2-year-o ld cell suspensions of Taxus cuspidata, cell line FCL1F, and in develo ping callus cultures of T. cuspidata. All compounds tested were includ ed in media at stationary phase (suspensions) or after the period of f astest growth (calli). Alanine and 3-amino-3-phenyl-propionic acid wer e tested only in callus cultures and did not affect taxol accumulation . Significant increases or trends toward increases in taxol accumulati on in callus and suspensions were observed in the presence of phenylal anine, benzoic acid, N-benzoylglycine, serine, and glycine. The greate st increases in taxol accumulation were observed in the presence of va rious concentrations of phenylalanine (1 mM for callus; 0.05, 0.1, and 0.2 mM for suspensions) and benzoic acid (0.2 and 1 mM for callus and 0.05, 0.1, and 0.2 mM for suspensions). Increases in taxol yields of cell suspensions in the presence of the most effective precursors brou ght taxol amounts at stationary phase from 2 mu g.g(-1) to approximate ly 10 mu g.g(-1) of the extracted dry weight. The results are discusse d in terms of possible implications to taxol biosynthesis and in terms of practical applications to large-scale cell culture systems for the production of this drug. (C) 1994 John Wiley and Sons, Inc.