Abstract
A strain of yeast which utilizes phenols was isolated from activated sludge for sewage treatment with a medium containing phenol as a sole carbon source. The yeast can oxidize p-cresol after the cells had been incubated in a medium containing phenol. An oxidation product from p-cresol, which accumulated in the reaction mixture, was isolated and crystallized. Ultraviolet, infrared, and nuclear magnetic resonance spectra, and the result of elemental analysis of the oxidation product assigned its structure to be 5-formyl-2-hydroxy-4-methyl-2, 4-pentadienoic acid. An identical compound was obtained by oxidation of 4-methylcatechol with yeast cells. These results suggest that, in the phenol-adapted yeast, an enzyme sequence is formed, by which p-cresol is oxidized to 4-methylcatechol and its benzene ring is cleaved between carbons 1 and 6.