Chemical content profile and antioxidant activity of Rhododendron ponticum L. (Ericaceae) extracts

Rhododendron species (Ericaceae) is considered the most diverse group, with more than 1200 species famous for their colorful flowers. Rhododendron, also known as azalea, is a flowering tree in the Ericaceae family. Herein, in vitro antioxidant activities of acetone and methanol extracts of Rhododendron ponticum leaves were studied along with their phenolic contents using High-Performance Liquid Chromatography with a Diode-Array Detector (HPLC-DAD). Antioxidant activity was performed spectrophotometrically using ABTS·+, DPPH·, CUPRAC, and β-carotene/linoleic acid assays. Acetone extract showed better antioxidant activity than methanol extract in all tests. The HPLC-DAD analysis revealed fifteen phenolic compounds, of which seven were common for both extracts. Catechin (25.80 and 33.08 mg/g extract, respectively) and epicatechin (31.15 and 26.54 mg/g extract, respectively) were calculated as major phenolic components in acetone and methanol extracts.