Chiral thioacetyl derivatives of proline as novel potential agents for beluga reproduction

The aim of the research was to study antioxidant activity and protective potential of new phenol-containing thioacetyl derivatives of D- and L-prolines as potential agents on beluga sperm and survival in the early stages of ontogeny of bester (Huso x Acipenser ruthenus) development. The study indicated that both enantiomers demonstrated the equal scavenging activity towards DPPH^•, ABTS^•+, O₂^•–, H₂O₂ and NO, and that the activity towards all of these radicals, with the exception of nitric oxide, exceeded the activity of BHT. No significant differences were registered between the enantiomers in the inhibition of long-term lipid peroxidation of beluga sperm in vitro. The enantiomers revealed the opposite effect on the motility duration time of beluga spermatozoa, the rate of their fertilization, and survival at the early stages of bester ontogeny. Application of the L-proline derivative for the beluga sperm treatment resulted in the increase of the total period of movement of beluga sperm cells, the raise of the fertility of sterlet eggs and the survival of bester offspring at the prelarval stage, which led to an increase in the number of produced larvae. The introduction of the D-proline derivative or BHT decreased the motility duration time of beluga sperm, the fertility of sterlet eggs and the survival of offspring at the prolarval stage, which led to a decrease in the number of obtained larvae.