Pharmacognostical and phytochemical screening and antioxidant activity of Stevia rebaudiana bertoni leaves

This research comprises microscopic observation, phytochemical screening, determination of total phenolic and flavonoid contents and antioxidant activity of Stevia rebaudiana Bertoni cultivated in Syria. Distinct elements were observed in the leaves, including multicellular tentacles, as well as pollen grains and tentacles in the flowers. Phytochemical screening showed the presence of flavonoids and coumarins, and the absence of saponins, anthraquinones, tannins, alkaloids, and cardiac glycosides. The highest phenolic content was 8.867 mg/g dry plant in the ethanolic extract, the highest flavonoid content was 2.89mg/g dry plant in the Aqueous extract. In interaction with diphenyl picryl hydrazyl, the inhibitory concentrations of half of free radicals ranged from 0.54 mg/mL in the ethanolic extract to 1.537 mg/mL in PG with water extract. The study showed that the ethnanolic extract of Stevia rebaudiana have good phenolic and flavonoid contents and good free radical scavenging activity.