Impact of molecular interactions with phenolic compounds on food polysaccharides functionality.

Commercial trends based of the emergence of plant-based functional foods lead to investigate the structure-function relationship of their main bioactive constituents and their interactions in the food matrix and throughout the gastro-intestinal tract. Among these bioactive constituents, dietary polysaccharides and polyphenols have shown to interact at the molecular level and these interactions may have consequences on the polysaccharides physical and nutritional properties. The methods of investigation and mechanisms of interactions between polysaccharides and polyphenols are reviewed in light of their respective technological and nutritional functionalities. Finally, the potential impact of the co-occurrence or co-ingestion of polyphenols and polysaccharides on the technological and nutritional functionality of the polysaccharides are investigated.

Effect of an anxiolytic botanical containing Souroubea sympetala and Platanus occidentalis on in-vitro diazepam human cytochrome P450-mediated metabolism.

OBJECTIVES: A novel anxiolytic natural health product (NHP) containing Souroubea sympetala and Platanus occidentalis is available for the companion animal market and is currently being developed for clinical evaluation. Addressing the risk of potential NHP-drug interactions, this study investigated S. sympetala and P. occidentalis plant extracts, and their identified bioactive compounds, for effects on the activity of cytochrome P450 (CYP) isozymes and the metabolism of the conventional anti-anxiety medication diazepam. METHODS: Souroubea sympetala and P. occidentalis extracts, a 1 : 1 blend of the two extracts, and five triterpenes were tested for inhibitory effects on human recombinant CYP3A4, CYP2D6, CYP2C9 and CYP2C19 activity using a fluorometric plate assay. Direct effects on the metabolism of diazepam were evaluated using human liver microsomes with drug and metabolite quantification by ultra-high-pressure liquid chromatography and mass spectroscopy. KEY FINDINGS: The active substances betulinic acid (BA) and ursolic acid (UA) strongly inhibited CYP3A4 activity while UA and lupeol moderately inhibited CYP2C19. All extracts exhibited strong activity against the tested isozymes at 50-100 µg/ml. BA and all plant extracts blocked the formation of major diazepam metabolites. CONCLUSIONS: Betulinic acid, UA and both the extracts and blended product are expected to affect the metabolism of diazepam when given in high dose.