Investigation of the effect of biologically active threo-Ds-isocitric acid on oxidative stress in Paramecium caudatum.

The effect of biologically active form (threo-Ds-) of isocitric acid (ICA) on oxidative stress was studied using the infusorian Paramecium caudatum stressed by hydrogen peroxide and salts of some heavy metals (Cu, Pb, Zn, and Cd). ICA at concentrations between 0.5 and 10 mM favorably influenced the infusorian cells with oxidative stress induced by the toxicants studied. The maximal antioxidant effect of ICA was observed at its concentration 10 mM irrespective of the toxicant used (either H2 O2 or heavy metal ions). ICA was found to be a more active antioxidant than ascorbic acid. Biologically active pharmaceutically pure threo-Ds-ICA was produced through cultivation of the yeast Yarrowia lipolytica and isolated from the culture liquid in the form of crystalline monopotassium salt with a purity of 99.9%.