Phytochemical Profile and Antioxidant Properties of Verbascum cheiranthifolium Boiss. from Kolakchal, Alborz Mountains in northern Tehran: A GC-MS Based Study

Verbascum cheiranthifolium, an endemic medicinal herb native to Iran, has long been employed in traditional medicine to treat rheumatism, earaches, menstrual irregularities, and inflammatory disorders. Nevertheless, its phytochemical composition and antioxidant potential remain insufficiently investigated. To fill this knowledge gap, aerial parts of V. cheiranthifolium were harvested from the Alborz Mountains (approx. ۲۵۰۰ m altitude) and subjected to comprehensive phytochemical and antioxidant analyses. Qualitative screening of the crude aerial parts demonstrated the occurrence of flavonoids, phenolics, tannins, saponins, and triterpenoids, whereas alkaloids and resins were absent. Among the extraction solvents tested, methanol provided the highest yield of compounds associated with antioxidant potential. The leaf-derived diethyl ether extract was analyzed using gas chromatography-mass spectrometry (GC–MS), which led to the identification of six major constituents, with n-eicosane (۷.۱۹%) being the most abundant, followed by n-pentacosane (۳.۳۱%). Spectrophotometric quantification revealed a total phenolic content of ۴.۹۰ ± ۰.۱۱ mg gallic acid equivalents (GAE) per gram of dry weight, which was low compared to previous reports. However, an exceptionally high total flavonoid content of ۴۹.۰۵ ± ۰.۹۴ mg quercetin equivalents (QE) per gram was observed, suggesting a chemotypic adaptation to high-altitude stress. The methanolic extract exhibited a concentration-dependent capacity to scavenge free radicals in the ۲,۲-diphenyl-۱-picrylhydrazyl (DPPH) radical scavenging assay, with an IC₅₀ value of ۷۹.۷ µg/mL. In contrast, the synthetic antioxidant butylated hydroxytoluene (BHT) achieved an IC₅₀ below ۵۰ µg/mL. Collectively, these results offer compelling experimental evidence for the ethnomedicinal relevance of V. cheiranthifolium and underscore its promise as a natural source of antioxidant agents for prospective nutraceutical and pharmaceutical exploitation.

کلیدواژه ها:

Verbascum cheiranthifolium ، Phytochemical screening ، Antioxidant activity ، Total phenolic content ، Flavonoids