Two triterpenoid glycosides from the roots of Camellia oleifera and their cytotoxic activity

Abstract

Two new triterpenoid saponins, oleiferoside N and oleiferoside O, were isolated from the EtOH extract from the roots of Camellia oleifera C. Abel. Their structures were elucidated as 16α-acetoxy-21β,22α-O-diangeloyloxy-23,28-dihydroxyolean-12-ene 3β-O-β-d-xylopyranosyl-(1 → 3)-α-l-arabinopyranosyl-(1 → 3)-β-d-glucuronopyranoside (1), 16α-acetoxy-21β-O-angeloyloxy-23,28-dihydroxy-22α-O-(2-methylbutanoyloxy)olean-12-ene 3β-O-β-d-xylopyranosyl-(1 → 3)-α-l-arabinopyranosyl-(1 → 3)-β-d-glucuronopyranoside (2), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and acid hydrolysis. Both were characterized to be oleanane-type saponins with sugar moieties linked to C-3 of the aglycone. Cytotoxic activities of two saponins were evaluated against four human tumor cell lines (A549, B16, BEL-7402, and MCF-7) by using the MTT in vitro assay. Compounds 1 and 2 showed moderate cytotoxic activities toward the tested cell lines.

Keywords::

• Camellia oleifera
• Theaceae
• triterpenoid saponins
• oleiferosides N–O
• cytotoxic activities

Acknowledgment

We are grateful to Dr Jon Parcher at the University of Mississippi for helpful discussions.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).