HPLC-DAD profile of phenolic compounds and antioxidant activity of leaves extract of Rhamnus alaternus L.

This research investigated the polyphenols profiling and antioxidative properties of Rhamnus alaternus L. A comparative analysis of the defatted and eluted fractions of methanol extract from leaves of R. alaternus L. was performed on high-performance liquid chromatography coupled to diode array detection. The total phenolic, flavonoid, monomeric anthocyanin contents, and antioxidant activity of all the fractions of the leaves extract were quantified. All fractions showed the presence of phenolic compounds and exhibited different levels of free radical scavenging activity. Seven individual phenolic compounds and anthraquinones as a group of phenolic compounds in the samples were identified. Luteolin, quercetin-3-rhamnoside, p-coumaric acid, ferulic acid, gallic acid, and rutin were the newly identified compounds in the extract, confirmed by the presence of kaempferol and anthraquinones. Knowledge of these compounds in the leaves extract will help in formulating pharmaceutical products for various diseases.