Acta Scientiarum Polonorum Technologia Alimentaria

Background. PABA is a growth factor; however, some papers report on the inhibiting effect of its high doses on the growth of yeast. The aim of this work was to examine the influence of PABA on growth of yeast, biomass yield, nitrogen and protein content and yeast cell morphology during cultivation on mineral and molasses media.

Material and methods. Cultures of bakery yeast Saccharomyces cerevisiae 2200 were run for 24 h at 28°C on a shaker at 200 rpm on mineral and molasses culture media containing  0.02, 1, 5, 10, 25, 50, 100, and 200 μg PABA in 1 cm³.

Results. The 200 μg dose of PABA in 1 cm³ of  mineral medium resulted in the strongest growth inhibition of yeast and the lowest biomass yield. PABA addition in the molasses medium did not change the growth dynamics of the examined strain.

Conclusions. At high doses, PABA functioned as a compound that inhibited and altered the yeast growth in the mineral medium. PABA doses ranging from 0.02 to 100 μg PABA·cm^-3 were found to evoke an increase in the nitrogen content of the cellular biomass. Upon the addition of PABA, yeast cultured in the mineral medium demonstrated
a tendency to increase sizes, whereas those cultured in the molasses medium to decrease their sizes.