Anthelmintic bioactivity against gastrointestinal nematodes has been associated with leguminous forages supporting the hypothesis of a role of condensed tannins. However, the possibility that other compounds might also been involved has received less consideration. Using bio-guided fractionation, the current study aimed at characterizing the biochemical nature of the active compounds present in sainfoin (Onobrychis viciifolia), previously identified as an anthelmintic leguminous forage. The effects of sainfoin extracts were evaluated on 3rd-stage larvae (L3) of Haemonchus contortus by using a larval migration inhibition (LMI) assay. Comparison of extracts obtained with several solvent systems showed that the bioactivity was associated with the 70[ratio ]30 acetone/water extract. Further fractionation of the later allowed the separation of phenolic compounds. By use of a dialysis method, compounds were separated with a molecular weight cut-off of 2000 Da. The in vitro anthelmintic effect of the fraction with condensed tannins was confirmed. In the fraction containing molecules of MW <2000 Da, 3 flavonol glycosides were identified as rutin, nicotiflorin and narcissin. At 1200 μg/ml, each inhibited significantly the migration of larvae. Addition of polyvinyl pyrrolidone (PVPP) to both fractions before incubation restored larval migration. These results confirmed the role of both tannins and flavonol glycosides in the anthelmintic properties of sainfoin.

Galipea officinalis Hancock is a shrubby tree reputed in folk medicine for its many properties which may be related to its alkaloid composition. We present in this paper the structural elucidation of five quinoline alkaloids: cuspareine, cusparine, and galipine, that have been previously described, demethoxycusparine, newly isolated in this species of Galipea and a new quinoline alkaloid named galipinine which is the 3′,4′-methylenedioxycuspareine.

Crude extracts of the aerial parts of Marrubium vulgare show a potent in vitro inhibition of KCl-induced contraction of rat aorta. Bio-guided fractionations, spectroscopic analysis and chemical derivatization revealed the furanic labdane diterpenes marrubenol and marrubiin as the most active compounds.