Acute toxicity of hydroalcohlic extracts of Heracleum persicum (Golpar) in zebrafish (Danio rerio Hamilton)

Heracleum persicum (HP) is an annual herbbelonging to Apiaceae (Umbelliferae) family and traditionally cultivated in Iran for its medicinal properties. Preliminary phytochemical analysis of H. persicum extract has shown that it possesses antioxidant properties, which may be attributed that to the presence of furanocoumarin compounds. In an experiment involving Danio rerio were, six groups of fish were exposed to different concentration of HA-PA ranging from 470 to 500 mg distributed among six groups in triplicates included G1 (control), G2 (1000 mg/kg), G3 (2000 mg/kg), G4 (4000 mg/kg), G5 (8000 mg/kg) and G6 (16000 mg/kg). The probit value for HA-HP and associated concentrations indicated low toxicity in D. rerio. The LC50 of HA-HP for D. rerio exposed to various concentrations for 24 hrs was found to be 6020.37 mg/kg with lower and upper bounds of 4477.5 and 8117.9, respectively at a 95% confidence limit. The maximum value of buccal movement rate was observed in animals exposed to 16000 mg/kg of HA-HP measuring between 134.0-192.66 N/min. However, increased doses of HA-HP led to respiratory distress and a decrease in oxygen uptake in fish. Moribund fish were observed at 1000 and 2000 mg/kg with signs of darting swimming, circular movement, and settling on the bottom of the aquarium for up to 12 hrs. The exposure of D. rerio to increasing concentration of HA-HP also resulted in the Loss of schooling behavior, which could affect their ability to move in coordination with their peers. Based on these findings, it can be concluded that the LD50 of HA-HP for D. rerio after 24 hrs is high indicating it can be used safely as an immunostimulant or for other purposes in fish at lower dosages.