Chemical Constituents from the Stem Bark of Garcinia urophylla Scort. ex King and their Antioxidant and Acetylcholinesterase Inhibitory Activities

Abstract

Members of the Clusiaceae family, including the Garcinia genus, are well-known for their diverse array of bioactive compounds, such as polyisoprenylated benzophenones, xanthones, and biflavonoids. This study focused on investigating the phytochemicals extracted from the stem bark of Garcinia urophylla and evaluating their antioxidant and acetylcholinesterase (AChE) inhibitory activities. The extraction was carried out using a cold maceration method, applying a polarity gradient of solvents: hexane, ethyl acetate, and methanol. The isolated phytochemicals were purified using chromatographic techniques, and their structures were elucidated through spectroscopic analyses (IR, NMR, and MS) and comparison with existing literature. The antioxidant activity of the compounds was assessed using the DPPH radical scavenging assay, while their AChE inhibitory activity was evaluated using the Ellman method. The isolation process successfully identified eight compounds: α-mangostin (1), β-mangostin (2), β-amyrin (3), lupeol (4), lupeol acetate (5), ferulic acid (6), syringic acid (7), and caffeic acid (8). Among these, compound (1) exhibited the most potent activity, with IC50 values of 15.2 µg/mL for DPPH radical scavenging and 18.0 µg/mL for AChE inhibition. These findings provide valuable insights into the potential nutraceutical and pharmaceutical applications of Garcinia species and their bioactive constituents. © 2025 Malaysian Institute of Chemistry. All rights reserved.