In vitro toxicity evaluation of flavonoid and alkaloid extracts from Smyrnium olusatrum using two model organisms: Artemia salina and Tetrahymena thermophila

This study investigates the cytotoxic potential of flavonoid and alkaloid extracts from Smyrnium olusatrum using two in vitro bioassays: the Artemia salina brine shrimp lethality test and the Tetrahymena thermophila viability assay. In A. salina, both extracts produced a concentration-dependent but overall weak toxic effect, with mortality stabilizing at moderate levels and LC50 values exceeding 500 µg/mL. The lethality of potassium dichromate confirmed the validity of the assay system. In T. thermophila, turbidity assessment, morphological observations, growth evaluation, and viability analysis all indicated mild cytotoxicity. Flavonoids caused no structural alterations and only slight growth inhibition, whereas alkaloids induced moderate morphological changes at the highest concentration tested. IC50 and LC50 values above 700 and 569 µg/mL, respectively, confirmed limited toxicity. Comparative interpretation of both biological models suggests that the extracts do not exert strong membranolytic or acute cytotoxic effects and only modestly affect protozoan cell physiology. These findings indicate that the tested flavonoid and alkaloid fractions possess low toxicity profiles and highlight the need for further toxicological studies and pharmacological evaluation.