Triterpene glycosides from the Vietnamese sea cucumber Holothuria edulis

Abstract

From the MeOH extract of the Vietnamese sea cucumber Holothuria edulis, eight triterpene glycosides (1–8), including one new compound namely holothurin A₅ (1), were isolated by using various chromatographic separations. Their structures were established by spectroscopic experiments including 1D, 2D NMR and HR-ESI-MS. Holothurin A₅ (1) has a hydroperoxy group at C-25. To the best of our knowledge, this is the first report of this group in triterpene saponins obtained from sea cucumbers to date. In addition, the in vitro cytotoxicity against five human cancer cell lines (HepG2, KB, LNCaP, MCF7 and SK-Mel2) of all isolated compounds was also evaluated using SRB assays.

GRAPHICAL ABSTRACT

Keywords:

• Holothuria edulis
• holothuriidae
• triterpene glycoside
• cytotoxicity

Acknowledgements

The authors are grateful to the Institute of Chemistry, VAST for measurement of the NMR spectra.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research is supported by Vietnam Academy of Science and Technology [grant number VAST.TĐ.DLB.03/16-18 and QTRU01.04/18-19] and grant number 18-53-54002 Viet_a from the RFBR (Russian Foundation for Basic Research).