Rat intestinal sucrase inhibition of constituents from the roots of Rosa rugosa Thunb.

A new octanordammarane triterpene, 3β,15α-dihydroxymansumbinol (1) and a novel A-ring contracted oleanane triterpenoid, 2-formyl-(A)1–19α-hydroxy-1-norolean-2,12-dien-28-oic acid (2) were isolated from the roots extract of Rosa rugosa along with fifteen known compounds (3–17). Their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR, and FTICRMS. The MeOH extract, as well as CH₂Cl₂ and EtOAc fractions at a concentration of 0.5 mg/mL showed potent sucrase inhibitory activity, with inhibition percentage values of 84.67 ± 5.37%, 87.50 ± 2.78%, and 81.91 ± 2.90%, respectively. In addition, compounds 7–13 (1.0 mM) showed potent sucrase inhibitory activity (61.88 ± 3.19% to 84.70 ± 3.07% inhibition), which was comparable to that of the positive control, acarbose, with an inhibition percentage value of 50.96 ± 2.97%. Compounds 1, 2, 4, and 14–17 showed moderate and/or weak inhibitory activities at the same concentration. The α-glucosidase inhibitory activities of the extracts and purified compounds may provide a novel opportunity to develop a new class of antidiabetic agents.