[The effect of acetic acid and furfural on yeast growth]

Acetic acid and furfural are normal components of the yeast hydrolysates. The influence of acetic acid in different concentrations (from 2 to 10 g/dm3) and furfural (from 0.2 to 0.8 g/dm3) on the growth of 8 yeast strains from the genus Candida under cultivation in synthetic nutrient media has been studied. It was established that some yeast strains absorb acetic acid better at pH 4.0-5.0, while others--only at pH 6.0 and at different concentrations of the acid in the nutrient media. Acetic acid in concentrations from 2 to 4 g/dm3 suppresses growth entirely in some strains, while in others growth was established. Acetic acid in concentrations over 8 g/dm3 inhibits growth in all 8 strains of the studied yeasts. Furforal in concentration to 0.4 g/dm3 in the synthetic nutrient media inhibits the growth in the 8 strains to a certain extent, while in concentration over 8 g/dm3 it stops the growth in all 8 yeast strains.