Investigation of phytochemical profiling and biological activities of methanol extract from Eryngium billardieri: antimicrobial, antibiofilm, and anthelmintic properties

The genus <i>Eryngium</i>, belonging to the Umbelliferae family, comprises flowering plants with various pharmacological activities, including anti-inflammatory and antidiabetic properties. However, many of these activities lack scientific evaluation. This study aimed to characterize the metabolites and evaluate the antihelmintic, antibacterial, and antibiofilm activities of a methanolic extract derived from the aerial parts of <i>Eryngium billardieri</i>. Metabolite characterization was conducted using LC-MS combined with a computer-assisted structure elucidation method. The extract was tested against six fungi, six Gram-positive bacteria, and nine Gram-negative bacteria, and a non-parasitic nematode (<i>Caenorhabditis elegans)</i>. A total of thirty-three compounds were identified, with the major constituents including isorhamnetin-3-O-glucoside, phytolaccagenin, terpinolene, 3,4-dimethoxybenzaldehyde, palmitic acid, isobornyl formate, isorhamnetin, and 1,4-dimethyl-7-(1-methylethenyl)-octahydroazulene. Across all tested concentrations, Gram-positive bacteria demonstrated greater sensitivity compared to Gram-negative bacteria, with <i>Staphylococcus aureus</i> and <i>Micrococcus luteus</i> showing the highest sensitivity (IC₅₀ values of 57.47 µg/mL and 105.8 µg/mL, respectively). Among Gram-negative strains, only <i>Brevundimonas diminuta</i> exhibited sensitivity. In antifungal tests, six of seven yeast strains displayed sensitivity to the extract, with <i>Candida parapsilosis</i> and <i>Candida albicans</i> being particularly susceptible (IC₅₀ values of 11.29 µg/mL and 63.29 µg/mL, respectively). The antibiofilm analysis demonstrated inhibitory effects within 24 hours after biofilm formation, with an IC₅₀ of 6.3 µg/mL. Additionally, the antihelmintic assay revealed a mean inhibition rate of 97.7 ± 1.5 at 2.0 µg/mL. The results demonstrate that the extract effectively inhibited the tested bacteria, particularly against yeast strains. While the extract showed promising activity against a model nematode, further research is imperative to validate its anthelmintic efficacy against parasitic nematodes.