Isolation and antihyperglycemic activity of bakuchiol from Otholobium pubescens (Fabaceae), a Peruvian medicinal plant used for the treatment of diabetes.

The known compound bakuchiol (1) was isolated from an extract of Otholobium pubescens (Fabaceae) by bioassay-guided fractionation using the db/db mouse model for type 2 diabetes. Oral administration of 1 reduced blood glucose levels in a dose-dependent fashion in db/db mice and did not display a hypoglycemic effect when tested in lean mice at 250 mg/kg q.d. Compound 1 was further evaluated in a new rodent model for type 2 diabetes, the fat-fed, streptozotocin (STZ)-treated rat. In this model, an oral dose of 1 at 150 mg/kg q.d. significantly lowered plasma glucose and triglyceride levels.

Maprouneacin, a new daphnane diterpenoid with potent antihyperglycemic activity from Maprounea africana.

Bioassay-guided fractionation of the EtOH extract of M. africana, using the in vivo noninsulin-dependent diabetes mellitus db/db mouse model, resulted in the isolation of the new daphnane-type diterpenoid maprouneacin (2). Compound 2 showed potent glucose-lowering properties when given by the oral route.