Phytochemical profiling and anthelmintic potential of rhizome of Swertia petiolata against Haemonchus contortus: an integrated in vitro and in silico approach.

Swertia petiolata has been traditionally used in folk medicine for treating parasitic infections. This study is aimed at phytochemical investigation and evaluation of anthelmintic properties of the Swertia petiolata against Haemonchus contortus. Plant material was collected, authenticated, dried, powdered and Soxhlet extracted using solvents (hexane, ethyl acetate and methane) in increasing order of their polarity. The extracts were evaluated for anthelmintic activity using Adult Motility Assay and Egg Hatch Assays. The most active extract was subjected to phytochemical investigation using column chromatography and semi preparatory-high-performance liquid chromatography techniques. The isolated compounds were characterized using nuclear magnetic resonance and mass spectroscopy. Additionally, the isolated phytochemicals were evaluated for their anthelmintic activity, and molecular docking and molecular dynamic simulation was conducted against β-tubulin (PDB ID: 1SA0) using AutoDock 4.20, and GROMACS with albendazole as the reference ligand. The ethyl acetate extract showed the highest anthelmintic activity and displayed prominent bands on thin layer chromatography. Three major xanthone derivatives, 1-hydroxy-3,5-dimethoxyxanthone, 1,3-dihydroxy-5,8-dimethoxyxanthone, and 1,8-dihydroxy-3,5-dimethoxyxanthone were isolated. Among them, 1-hydroxy-3,5-dimethoxyxanthone exhibited the strongest in vitro activity, consistent with molecular docking results that indicated its highest binding affinity toward β-tubulin. Overall, the study demonstrates that S. petiolata, particularly its ethyl acetate extract, possesses significant anthelmintic potential. The combined in vitro and in silico findings highlight 1-hydroxy-3,5-dimethoxyxanthone as a promising lead compound targeting β-tubulin and impairs microtubule formation in H. contortus.