Abstract: The effects of two phenolic compounds in lignocellulosic hydrolysate, p-hydroxybenzaldehyde and ferulic acid, on the physicochemical properties of Saccharomyces cerevisiae GGSF16 were studied. Results showed that after treatment with either compound, the glucose metabolism time and alcoholic fermentation time of S. cerevisiae was extended, the contents of extracellular nucleic acid and protein and the content of intracellular trehalose were significantly increased (P < 0.05). Scanning electron microscopic (SEM) images showed that the surface morphology changed from complete and smooth to wrinkled, sticky and cracked. In addition, functional groups of lipids, proteins, nucleic acids were altered as shown by Fourier transform infrared (FTIR) spectra. Collectively, these findings indicated that the p-hydroxybenzaldehyde and ferulic acid can cause damage to S. cerevisiae cell wall and increase cell membrane permeability, thereby resulting in leakage of cell contents, finally causing cell damage.

Key words: p-hydroxybenzaldehyde; ferulic acid; Saccharomyces cerevisiae; physicochemical properties