Appraisal of a new potential antioxidants-rich nutraceutical ingredient from chestnut shells through in-vivo assays – A targeted metabolomic approach in phenolic compounds

Chestnut (Castanea sativa) shells (CSS) are a source of bioactive compounds with well demonstrated in-vitro antioxidant properties. Nevertheless, no in-vivo studies have already evaluated this effect. This study evaluated the effects of the oral daily administration of an eco-friendly CSS extract (50 and 100 mg/kg per body weight (b. w.)) to rats regarding in-vivo antioxidant activity, glucose and lipids levels, and metabolomic profiling of poly- phenols by LC-ESI-LTQ-Orbitrap-MS. The results demonstrated the in-vivo antioxidant properties in the animals liver, kidney and blood serum, as well as protective effects against hemolysis and rising of blood glucose and lipids levels. New insights on metabolomic profiling of polyphenols proved their absorption and further biotransformation by phase I (hydrogenation and hydroxylation) and II reactions (glucuronidation, methylation and sulfation). This is the first study that attempted to validate a novel nutraceutical ingredient extracted from CSS by in-vivo assays, corroborating the outcomes screened by in-vitro assays