Toxic effect of extracts of Peganum harmala and Euphorbia guyoniana on Androctonus australis (Scorpiones; Buthidae)

Abstract

Peganum harmala and Euphorbia guyoniana are two medicinal plants known for their phytochemical constituents and biological activities. This study aimed to investigate the toxic potential of ethanolic extracts of both plants against the scorpion Androctonus australis collected from the Ghardaïa region, Algeria.
Phytochemical screening and high-performance liquid chromatography (HPLC) were carried out to characterize the extracts. The toxicological activity was evaluated at five concentrations (10, 15, 20, 25, and 30 mg/mL), using 5% DMSO as a control, by monitoring mortality and locomotor inhibition over 72 h. Molecular docking was also performed to investigate the interactions between selected phytochemicals and acetylcholinesterase.
The extraction yield was higher for E. guyoniana (5.10%) than for P. harmala (3.44%). Phytochemical screening revealed the presence of several secondary metabolites, particularly flavonoids, tannins, alkaloids, and phenolic compounds. The results showed that mortality increased with extract concentration and exposure time, reaching approximately 60% at the highest concentrations after 72 h. Locomotor inhibition was also more pronounced at higher concentrations. Molecular docking results suggested that several phytochemicals could interact with acetylcholinesterase.
Overall, the results indicated that the ethanolic extracts of P. harmala and E. guyoniana exerted toxicological and behavioral effects against A. australis under the experimental conditions tested, suggesting their potential as sources of bioactive compounds for further investigation.