Phytochemical properties and antioxidant activity of Echinops persicus plant extract: green synthesis of carbon quantum dots from the plant extract

摘要： Echinops persicus is a species of Echinops that can be found in Europe and western Asia especially in Iran. In this paper, the phytochemical properties of Echinops persicus were thoroughly investigated and studied. In this way, total amounts of flavonoid, tannins, phenols, carotenoids, saponins, alkaloids, and anthocyanin were measured by various analytical methods. The major phenolic and flavonoid content was found in the root acetone and flower ethanolic extract of the plant. Also, major saponins and carotenoid contents was found in root and leaf of the plant. These measurements were also performed for root, leaf, and flower of the plant in various solvent extracts. The results indicated that Echinops persicus is a rich source of secondary metabolites. Also, the plant extract demonstrated a considerable antiradical activity, which evaluated qualitatively as well as quantitatively. The largest capacity to neutralize DPPH radicals was found for root water extract of Echinops persicus plant. Finally, the possibility of the plant extract was evaluated for the green preparation of carbon quantum dots (CQDs). As-prepared CQDs were characterized by TEM, HRTEM, UV–Vis, XRD, and EDX analyses.