Antioxidant flavonol glycosides from Schinus molle

Area of Science:

• Phytochemistry
• Natural Products Chemistry
• Pharmacognosy

Background:

• Schinus molle L. is a plant species with a rich history of traditional medicinal use.
• Phytochemical investigations are crucial for identifying bioactive compounds from medicinal plants.
• Understanding the chemical constituents of S. molle can validate its traditional applications.

Purpose of the Study:

• To isolate and characterize new and known polyphenolic compounds from Schinus molle L. leaves.
• To evaluate the radical scavenging potential of the isolated compounds.
• To contribute to the phytochemical knowledge of the Schinus genus.

Main Methods:

• Extraction of S. molle leaves using aqueous methanol.
• Chromatographic separation techniques (e.g., HPLC) for isolating compounds.
• Spectroscopic analyses including UV, NMR (1H, 13C), and ESI-MS for structural elucidation.

Main Results:

• Isolation of two novel acylated quercetin glycosides: isoquercitrin 6''-O-p-hydroxybenzoate and 2''-O-alpha-L-rhamnopyranosyl-hyperin 6''-O-gallate.
• Identification of twelve known polyphenolic metabolites, including gallic acid, chlorogenic acid, isoquercitrin, and hyperin.
• Compounds 6 (miquelianin) and 7 (quercetin 3-O-beta-D-galacturonopyranoside) showed the strongest radical scavenging activity in vitro.

Conclusions:

• The study successfully identified new and known polyphenols from Schinus molle L. leaves.
• Several isolated compounds, particularly miquelianin and quercetin 3-O-beta-D-galacturonopyranoside, possess notable antioxidant properties.
• These findings support the ethnobotanical uses of S. molle and highlight its potential as a source of bioactive natural products.