Coumarins and flavones from the fruit and root extracts of Micromelum integerrimum

Abstract

A phytochemical investigation of the fruit and root extracts of Micromelum integerrimum resulted in the isolation and identification of a new compound, integerravone (1), together with 23 known compounds (2–24). Their structures were characterized by spectroscopic methods as well as comparisons made from the literature. Compounds 2, 3–15, 17–18 and 20–23 were evaluated for their cytotoxicities against the colon cancer cell line, HCT116. All of them were inactive at 50 µM. Most of the phenolic compounds were evaluated for their antioxidant activity using the DPPH assay. Compounds 14 and 22–24 showed antioxidant activity with IC₅₀ values ranging from 24.83-135.05 µM.

Graphical Abstract

Keywords:

• Micromelum integerrimum
• Rutaceae
• Coumarin
• Flavone

Acknowledgments

This work was supported by the joint research funding of Thailand Research Fund and Mae Fah Luang University through the Advanced Research Scholar (BRG5980012) and the Thailand Research Fund through the Direct Basic Research Grant (DBG5980001). A full Ph.D scholarship from the Thailand Research Fund through the Royal Golden Jubilee Ph.D. program (PHD/0133/2559) is also acknowledged. Mae Fah Luang University, University of Wollongong and University of British Columbia are also acknowledged for laboratory facilities. We also thank Mr. Martin Van de Bult from Doi Tung Development Project Chiang Rai Thailand for plants collection and identification.

Disclosure statement

The authors declare no conflicts of interest.

Additional information

Funding

This research was supported by the Thailand Research Fund through the Advanced Research Scholar (BRG5980012) and Direct Basic Research Grant (DBG5980001). A full Ph.D scholarship from the Thailand Research Fund through the Royal Golden Jubilee Ph.D. program (PHD/0133/2559).