PRODUCTION OF 2-PHENYLETHYL ALCOHOL BY KLUYVEROMYCES-MARXIANUS

Among the numerous yeasts able to produce flavor compounds, several st rains of Kluyveromyces species are known for the synthesis of large am ounts of aromatic compounds. In particular, the accumulation of 2-phen ylethyl alcohol in liquid cultures of Kluyveromyces marxianus was obse rved after incubation on a semisynthetic medium at 30 degrees C, 125 r pm. Changes in the carbon sources led to a significant modification of the amount of this aromatic compound; moreover, the variations in the level of DL-phenylalanine and the exclusive use of a precursor isomer (L) also affected the synthesis of 2-phenylethyl alcohol. Finally, th is study revealed the growth inhibition of K. marxianus when the conce ntration of 2-phenylethyl alcohol reached a critical value near 1.4 g/ L; the use of an exponential model allowed the inhibition constant k(i ) to be determined (k(i) = 0.35 g/L).