Chemical Characterization of the Hydroethanolic Extract of the Inner Stem Bark of Dilodendron bipinnatum. Comparative Cytotoxic Evaluation and Anti-inflammatory Potential of a Simple Mixture of its Isolates 3-O-β-Glucopyranosyl-β-sitosterol and 3-O-β-Glucopyranosyl-stigmasterol:

Phytochemical investigation of the hydroethanolic extract of the inner stem bark of Dilodendron bipinnatum (HEDb) by column chromatography led to the separation of three major fractions: a) a mixture of phytosterols (ST mixture), including β-sitosterol (1), stigmasterol (2) and campesterol (3); b) a mixture of 3-O-β-glucopyranosyl-β-sitosterol (4) and 3-O-β-glucopyranosyl-stigmasterol (5) (SGP mixture); and c) epicatechin (6), as a single isolate. Their structures were determined by spectrometric analysis using 1H- and 13C-NMR spectroscopy, and GC-MS. The safety profile of the SGP mixture, when evaluated on RAW 264.7 cells, using the alamar blue® assay, exhibited no cytotoxic effects. The anti-inflammatory activity was comparatively analyzed in vivo using the lipopolysaccharide (LPS)-induced peritonitis model in mice, showing a strong reduction of leukocyte migration to the peritoneal cavity using both the SGP mixture and the HEDb. In vitro assessment of nitric oxide (NO) in the macrophagic RAW 264.7 cell...