On 22 August, at VNUHCM–University of Science (HCMUS), doctoral researcher Nguyễn Thị Mỹ Hương successfully defended a doctoral thesis in Organic Chemistry entitled ‘Study on chemical constituents and biological activity testing of Melodorum fruticosum (Lour.) Merr., Annonaceae’. The research was conducted under the scientific guidance of Dr Ngô Thị Thùy Dương and Associate Professor Đỗ Thị Mỹ Liên.

Within the scope of the study, Nguyễn Thị Mỹ Hương focused on isolating, determining chemical structures, and evaluating key biological activities — including α-glucosidase enzyme inhibitory activity and cytotoxic activity — from the stems and roots of Melodorum fruticosum collected in Lam Dong province. To address complex requirements in structural elucidation, the author flexibly applied chromatographic extraction techniques combined with modern spectroscopic systems such as HR-ESI-MS, 1D/2D-NMR, ECD, and specific optical rotation measurements. The work contributed valuable scientific data on the biochemical composition and medicinal potential of this plant species in Viet Nam.

One of the most notable achievements of the thesis was successfully elucidating the structures of 42 compounds isolated from the stems and roots, belonging to various chemical classes including alkaloids, flavonoids, phenolics, and carboxylic acids. Remarkably, research results identified 32 compounds recorded for the first time in Melodorum fruticosum. Even more significantly, the project discovered and published 06 entirely novel compounds in nature, including pyronomelodorones A–B, (2S)-8-prenyl-5,6-dihydroxy-7-methoxyflavanone, (2S)-6-acetoxy-5-hydroxy-7-methoxyflavanone, (7’S)-3′-hydroxy linderagatin-A, and (2R)-2-hydroxy-6,7-methylenedioxy-2-(4-hydroxyphenyl)-1-tetralone. Additionally, the thesis provided a comprehensive spectroscopic dataset (1D, 2D-NMR, HR-ESI-MS, ECD, specific optical rotation), serving as an accurate reference for future research on natural product chemistry.

Regarding biological activity, testing revealed that most samples isolated from Melodorum fruticosum demonstrated strong α-glucosidase enzyme inhibition. Among these, compounds belonging to the flavonoid group showed particularly outstanding results with IC50 values ranging from 0.05 to 3.16 µM. This performance significantly surpassed the standard positive control acarbose (IC50 = 179.00 µM). The finding opens up promising prospects for developing products supporting diabetes treatment from natural medicinal sources.

Evaluating the work, the Evaluation Committee assessed that the research by Nguyễn Thị Mỹ Hương achieved high scientific quality and clear practical value. Findings from the thesis not only enrich the phytochemical database but also help guide the enhancement of value and sustainable exploitation of domestic medicinal resources.