Traditional use, Phytochemistry and Pharmacological Properties of the Genus Onopordum

Background: The genus Onopordum (Asteraceae), with about 40 species, is composed of perennials and spermatophyte plants, which are widely used in popular medicine for the treatment of several human diseases. Plants of this genus constitute an interesting source of bioactive molecules with a wide range of pharmacological applications. Objective: In this context, the current study describes a critical review of traditional uses, phytochemistry, and pharmacological effects of the genus Onopordum in order to establish a valuable database for future ethnopharmacological surveys on this genus. Methods: For this, all bibliographic data covering the period of 1970 to 2022 were collected and analyzed. Results: Only 19 species from the genus Onopordum were studied. They are traditionally used to treat gastric, renal, respiratory, urinary, and gynecological diseases and in the food industry for cheese production. Indeed, it was found that Onopordum species are rich in flavonoids, phenolic compounds, terpenoids, alkaloids, tannins, and steroids. These plants exhibit several interesting biological activities including: antioxidant, antimicrobial, antiproliferative, apoptotic, cytotoxic, antitumor, anticholinergic, larvicidal, analgesic and antipyretic, hypotensive, antiepileptic, and anticonvulsant activities. Furthermore, their hemostatic, anti-inflammatory, and moisturizing properties, increase their usefulness in the cosmetic field. Conclusion: According to the present study, Onoporadum species constitute an important natural source of secondary metabolites with potential therapeutic, cosmetic, and nutritional applications. However, the focus has been only on 19 species and the publications were not very explanatory, Therefore, in-depth pharmacological and phytochemical studies are needed to fully exploit the therapeutic potential and the chemical composition of Onopordum species.