Antioxidative compounds from Garcinia buchananii stem bark.

Area of Science:

• Natural Product Chemistry
• Pharmacognosy
• Medicinal Chemistry

Background:

• Garcinia species are known sources of bioactive compounds.
• Antioxidants play a crucial role in combating oxidative stress.
• The phytochemical profile of Garcinia buchananii requires further investigation.

Purpose of the Study:

• To isolate and characterize compounds from Garcinia buchananii stem bark.
• To evaluate the antioxidant potential of the isolated natural products.
• To identify novel bioactive molecules for potential therapeutic applications.

Main Methods:

• Aqueous ethanolic extraction of Garcinia buchananii stem bark.
• Activity-guided fractionation to isolate compounds.
• Structure elucidation using NMR, ECD spectroscopy, and polarimetry.
• In vitro antioxidant assays: H2O2 scavenging, ORAC, and TEAC.

Main Results:

• Isolation of three new compounds: isomanniflavanone, 1,5-dimethoxyajacareubin, and garcinisidone-G.
• Identification of six known compounds, all reported for the first time in this species.
• Demonstrated strong in vitro antioxidant activity, particularly for isomanniflavanone.

Conclusions:

• Garcinia buchananii is a rich source of antioxidant compounds.
• Isomanniflavanone exhibits potent free radical scavenging activity.
• These findings support the potential of Garcinia buchananii derivatives in antioxidant therapies.