RESUMO
The methanolic extract and 1-butanol-soluble fraction of American ginseng, the roots of Panax quinquefolium L., were found to exhibit a protective effect on liver injury induced by D-galactosamine and lipopolysaccharide. Five new dammarane-type triterpene oligoglycosides called quinquenosides I, II, III, IV, and V were isolated together with fourteen known dammarane-type triterpene oligoglycosides such as chikusetsusaponin IVa, pseudo-ginsenoside-RC1, malonyl-ginsenoside-Rb1, and notoginsenosides-A,-C, and -K from the 1-butanol-soluble fraction. From the ethyl acetate-soluble fraction, four known acetylenic compounds and 6'-O-acetyl ginsenoside-Rg1 were isolated. The structures of quinquenosides I, II, III, IV, and V were determined on the basis of chemical and physicochemical evidence as 3-O-[6-O-(E)-2-butenoyl-beta-D-glucopyranosyl(1-->2)-beta-D- glucopyranosyl]-20-O-(beta-D-glucopyranosyl) 20(S)-protopanaxadiol (quinquenoside I), 3-O-[6-O-(E)-2-octenoyl-beta-D- glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 20(S)-protopanaxadiol (quinquenoside II), 3-O-[beta-D-glucopyranosyl (1-->2)-6-O-acetyl-beta-D-glucopyranosyl]-20-O-(beta-D-glucopyranosyl) 20(S)-protopanaxadiol (quinquenoside III), 3-O-[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-beta-D- glucopyranosyl(1-->6)-beta-D-glucopyranosyl]-3 beta, 7 beta, 20(S)-trihydroxydammar-5,24-diene (quinquenoside IV), and 3-O-[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[alpha-D- glucopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ] 20(S)-protopanaxadiol (quinquenoside V).
Assuntos
Glicosídeos/química , Panax/química , Plantas Medicinais , Saponinas/química , Triterpenos/química , Animais , Galactosamina , Glicosídeos/isolamento & purificação , Glicosídeos/toxicidade , Lipopolissacarídeos , Fígado/efeitos dos fármacos , Fígado/patologia , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Saponinas/isolamento & purificação , Saponinas/toxicidade , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Relação Estrutura-Atividade , Triterpenos/isolamento & purificação , Triterpenos/toxicidadeRESUMO
The glycosidic fraction from the dried roots of Panax notoginseng (Burk.) F.H. Chen was found to show protective effect on liver injury induced by D-galactosamine and lipopolysaccharide. From the glycosidic fraction with hepatoprotective effect, nine new dammarane-type triterpene oligoglycosides, notoginsenosides-A, -B, -C, -D, -E, -G, -H, -I, and -J and an acetylenic fatty acid glycoside, notoginsenic acid beta-sophoroside, were isolated together with fourteen known dammarane-type triterpene oligoglycosides. The structures of notoginsenosides-A, -B, -C and -D were determined on the basis of chemical and physicochemical evidence, which included the chemical correlation with ginsenoside-Rb1 using photosensitized oxygenation, as follows: notoginsenoside A; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 3 beta, 12 beta,20(S),25-tetrahydroxydammar -23-ene; B; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D- glucopyranosyl] 3 beta, 12 beta,20(S)-trihydroxydammar-25-en-24-one, C; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D -glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 3 beta,12 beta,20(S)- trihydroxy-24 zeta-hydroperoxydammar-25-ene, and D; 3-O-[beta-D-xylopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-xylopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl]20(S)-protopanaxadiol, respectively.