Isolation and Characterization of Secondary Metabolites from the Twigs and Leaves of Diospyros phuwuaensis and their Cytotoxicity Activity

Abstract

The Diospyros genus includes diverse species that have been utilized for various purposes over the years, including food, high-quality timber, and traditional medicine. Diospyros phuwuaensis is a tree native to Thailand that presents an intriguing opportunity for research in natural product chemistry, as the types of chemicals and biological properties expected to be found in this plant remain largely unknown. Therefore, investigating and recording the biological activities and chemical constituents of this species is essential, greatly aiding the progress of research within the genus. Extraction of the dried, powdered twigs of D. phuwuaensis yielded hexane extract (0.28 wt%), crude ethyl acetate extract from twigs (0.52 wt%), and crude methanol extract from twigs (2.33 wt%). Similarly, extraction of the dried, powdered leaves of D. phawuaensis produced crude hexane extract from leaves (2.12 wt%), crude ethyl acetate extract from leaves (1.38 wt%), and crude methanol extract from leaves (6.13 wt%). The cytotoxicity study revealed that the crude ethyl acetate and crude methanol extracts of the leaves and twigs of D. phuwuaensis exhibited significant cytotoxicity against SH-SY5Y and MDA-MB-231 cell lines, with ED50 values ranging from 1.43 to 4.00 µg/mL, which are not as effective as the ellipticine used as a positive control in the experiment. Extraction and separation experiments also identified two major triterpenoids, friedelin (1) and uvaol (2). These compounds could be valuable building blocks for creating new molecules that exhibit enhanced biological activities.