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

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.