Cholinesterase inhibitory triterpenoids from the bark of Garcinia hombroniana

Abstract

Context: Garcinia hombroniana Pierre, known as manggis hutan in Malaysia is a rich source of xanthones and benzophenones.

Objectives: This study was aimed to isolate and characterize potential cholinesterase inhibitors from the extracts of G. hombroniana bark and investigate their interactions with the enzymes.

Materials and methods: The dichloromethane extract afforded five triterpenoids which were characterized by NMR and mass spectral techniques. Cholinesterase inhibitory assay and molecular docking were performed to get insight of the inhibitory activity and molecular interactions of the compounds. The compounds were also tested for their antioxidant capacity.

Results: The isolated triterpenoids were identified as: 2β-hydroxy-3α-O-caffeoyltaraxar-14-en-28-oic acid (1), taraxerol (2), taraxerone (3), betulin (4) and betulinic acid (5). Compound 1 was the most active dual inhibitor of both AChE and BChE. Compound 1 also showed good antioxidant activities.

Conclusion: Compound 1 had dual and moderate inhibitory activity on AChE and BChE worthy for further investigations.

• 2β-hydroxy-3α-O-caffeoyltaraxar-14-en-28-oic acid
• acetylcholinesterase
• butyrylcholinesterase
• molecular docking
• triterpenoids

Declaration of interest

The authors have no conflict of interest. The authors wish to acknowledge the Research University Grant (RU1001/PKIMIA/811129) provided by Universiti Sains Malaysia (USM). Nargis Jamila is thankful to TWAS and USM for the award of TWAS-USM PG fellowship.

Supplementary materials online only – For review only at proofing stage.