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.