Evaluation of biological activities of triterpenoid saponins from Maesa lanceolata.

From a bioassay-guided fractionation procedure using Herpes simplex virus type 1 as the target model, a virucidal saponin mixture (maesasaponin mixture B) was isolated from the MeOH extract of leaves of Maesa lanceolata. The maesasaponin mixture B consisted of six homologous oleanane-type triterpenoid saponins 1-6, identified by 1H, 13C, and 2D NMR spectroscopy and mass spectrometry. The maesasaponin mixture B (1-6) showed several biological activities expected for saponins. It exhibited a moderate virucidal activity against enveloped viruses. The maesasaponin mixture B (1-6) was tested for further properties. The saponin mixture was found to be highly hemolytic and molluscicidal: it hemolyzed 50% of human erythrocytes (1% suspension) at a concentration estimated at 1.6 microg/mL and exerted against Biomphalaria glabrata snails a severe toxic effect with LD95 and LD50 values of 4.1 and 2.3 ppm, respectively. In addition, the maesasaponin mixture B (1-6) showed moderate fungistatic and antimutagenic properties. The evaluation of these diverse activities is described.