It was determined that activity of β-fructofuranozydase in baker's yeast put through a uniform, constant, constant but pulsating, and alternating magnetic field with induction levels between 0 and 200 Gs at a linear speed of 2.5X 10⁻³ to 2.5 m/sec. was inhibited by 7.4% to 23% regardless of type of the field. Growth rate of aerobic cultivated baker's yeast was not effected.
Citrate fermentation was carried out on a medium with hydrolysed potato starch at 30°C using the strain Aspergillus. niger S. The obtained results demonstrate that liquefied starch (DE < 25) is a better substrate for the fermentation of citric acid than saccharified starch (DE> 80). The fermentation of liquefied starch was possible thanks to the ability of the applied Aspergillus niger S strain to produce its own amylolytic enzymes which saccharify starch to available sugars.