Ternifoliasaponin, a new triterpenoid saponin from the roots of Gardenia ternifolia Schumach & Thonn (Rubiaceae).

A new triterpenoid saponin, Ternifoliasaponin ( 1 ), together with four known compounds ( 2-5 ) chikusetsusaponin IVa ( 2 ), chikusetsusaponin IVa methyl ester ( 3 ), bonushenricoside B (4 ) and Dianoside C ( 5 ) were isolated from roots of Gardenia ternifolia Schumach. & Thonn (Rubiaceae). The structures of isolated compounds were elucidated on the basis of spectroscopic analysis and chemical methods. The antibacterial activities of compounds ( 3) , and ( 4) were performed by the Muller-Hinton agar diffusion method. The antimicrobial activities of the compounds were studied on Salmonella typhi (Enterobacteriaceae), Staphylococcus aureus and Pseudomonas aeruginosa microorganisms. Compound ( 3 ) at 25 mg/mL, showed moderately sensitive effect (8.0 ˂ DIZ ˂14.0 mm) on S. typhi , S. aureus and P. aeruginosa . Compound ( 4 ) at 25 mg/mL and compound ( 3 ) at 12.5 mg/mL exhibited moderately sensitive effect on S. typhi and S. aureus. Compound ( 4 ) inhibited moderately sensitive the S. typhi and P. aeruginosa colonies at 12.5 mg/mL.