Chemical Composition, Phytochemical Screening, and Antibacterial Potentials of the Aerial Parts of Eryngium thyrsoideum Boiss.

The chemical composition, phytochemical contents, and antibacterial potentials of the Eryngium Thyrsoideum Boiss. aerial parts were evaluated. The RP-HPLC-DAD method were applied to determine the phenolic and flavonoid contents of the extract. The hydrodistillation method with a Clevenger apparatus was used to isolate the essential oil, and the analyses of the oil was performed using GC-MS. Using the disc diffusion method and the broth microdilution assay, three gram-negative and six gram-positive bacterial strains were tested to assess the antibacterial effect of oil. The total flavonoid content of the extract was 0.81 ± 0.05 mg of quercetin equivalent per gram of dry plant materials, while its total phenolic content was 0.24 ± 0.01 mg of gallic acid equivalents per g of dry plant materials. According to the phytochemical screening results, phenols, flavonoids, steroids, glycosides, and saponins were detected in the ethyl acetate, n-hexane, and methanolic extracts. Results showed the existence of rutin, quercetin, and benzoic acid in the methanolic extract and revealed 46 compounds that constitute 93.07% of the obtained oil were recognized. Besides, 2,3,6-trimethyl benzaldehyde (24.15%), trans-4,10-epoxy-amorphane (15.55%), longifolene (13.72%), germacrene D (4.76%), 2,3,4-trimethyl benzaldehyde (4.67%), cis-chrysanthenyl acetate (3.3%), caryophyllene oxide (3.26%), and sesquicineole (2.78%) were identified in the oil as the major compounds. The oil showed in vitro significant inhibitory effect on Bacillus pumilus, Bacillus subtilis, and Staphylococcus epidermidis, resulting from its high proportion of sesquiterpenes. Regarding the different bioactive compounds and the antibacterial properties of Eryngium thyrsoideum, this plant can be applied in cosmetic, food, and pharmaceutical products.