ABSTRACT
A new steroidal saponin, 3-{(O-6-deoxy-a-L-mannopyranosyl-(1 --> 4)-O-beta-D-glucopyranosyl-(1 --> 3)-O-[O-beta-D-glucopyranosyl-(1 --> 3)-beta-D-glucopyranosyl-(1 --> 2)]-O-beta-D-glucopyranosyl-(1 --> 4)-beta-D-galactopyranosyl)oxy}-6-hydroxy-(3beta,5alpha,6alpha,25R)-spirostan-12-one, was isolated from Agave brittoniana Trel. The structure was determined by extensive NMR spectroscopy studies and chemical conversions. Its effects on the Na+-ATPase and (Na+ + K+)-ATPase activities of the proximal tubule from pig kidney were evaluated. It was observed that this steroidal saponin exerts a biphasic effect on the Na+-ATPase activity. It is concluded that the effect of the aqueous extract as a diuretic is due, at least in part, to the action of saponin on the ouabain-insensitive Na+-ATPase.
Subject(s)
Agave/chemistry , Saponins/chemistry , Saponins/pharmacology , Sodium-Potassium-Exchanging ATPase/metabolism , Steroids/chemistry , Steroids/pharmacology , Animals , Carbohydrate Conformation , Carbohydrate Sequence , Cell Membrane/enzymology , Kidney Tubules/enzymology , Kinetics , Methylation , Models, Molecular , Molecular Sequence Data , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Plant Leaves/chemistry , Saponins/isolation & purification , Sodium/pharmacology , Sodium-Potassium-Exchanging ATPase/drug effects , Steroids/isolation & purification , SwineABSTRACT
A polysaccharide, an alpha-D-glucan with an apparent molecular weight of 6.85 x 10(4), called PSa glucan, was isolated from fresh seeds of Sorghum arundinaceum by fractionation on Sephacryl S-300 HR and Sephadex G-25. Chemical and spectroscopic studies indicated that it has a highly branched glucan type structure composed of alpha-(1-->4) linked D-glucopyranose residues with (1-->3), (1-->6) branching points, and a significant amount of alpha-(1-->6) branching to alpha-(1-->3) linked D-glucopyranose residues. The anti-inflammatory activity of the polysaccharide was performed using the capillary permeability assay.
Subject(s)
Anti-Inflammatory Agents/chemistry , Edible Grain/chemistry , Polysaccharides/chemistry , Seeds/chemistry , Animals , Anti-Inflammatory Agents/pharmacology , Carbohydrate Conformation , Carbohydrate Sequence , Gas Chromatography-Mass Spectrometry , Male , Methylation , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Oligosaccharides/chemistry , Oligosaccharides/isolation & purification , Plant Extracts/chemistry , Polysaccharides/isolation & purification , Polysaccharides/pharmacology , SteroidsABSTRACT
A new steroidal saponin was isolated from the leaves of Agave attenuata Salm-Dyck. Its structure was established as (3beta,5beta,22alpha,25S)-26-(beta-D-glucopyranosyloxy)-22-methoxyfurostan-3-yl O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-O-[beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside. The structural identification was performed using detailed analyses of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques (COSY, HETCOR and COLOC) and chemical conversions. The haemolytic potential of the steroidal saponin was evaluated and the anti-inflammatory activity was performed using the capillary permeability assay.
