Estudios científicos

Does resveratrol retain its antioxidative properties in wine? Redox behaviour of resveratrol in the presence of Cu(II) and tebuconazole

Abstract:

 Resveratrol is antioxidant naturally occurring in wine grapes. It is thought to have a preventive biological activity against number of diseases. However, it has been recently shown that in the presence of metal ions, such as Cu2+, resveratrol forms oxidative radicals. Cu2+ is usually present in wine due to former usage of bluestone in vineyards. Fungicide tebuconazole has substituted bluestone and is presently one of the most widely used agrochemicals in wine industry; wine thus may contain traces of tebuconazole. Here, we study the ternary system of resveratrol, Cu2+, and tebuconazole experimentally and theoretically (using mass spectrometry, antioxidant capacity assay and quantum-chemical calculations) to model the redox behaviour of resveratrol in wine. We show that tebuconazole prevents formation of oxidative resveratrol radicals (induced by Cu2+ reaction with resveratrol) via preferential Cu2+ capture and protection of the binding sites of resveratrol. This positive effect of tebuconazole has not been observed before.

Comentarios divulgativos:

El resveratrol es un compuesto clave en el vino tinto que destaca por sus propiedades antioxidantes y se ha relacionado con mejoras en la salud. Sin embargo, se ha observado que en presencia de Cu2+, forma radicales oxidantes y este elemento está presente en funguicidas.
En este estudio los autores evalúan si el Cu2+ y el tebuconazol, un fungicida ampliamente utilizado, alteran la capacidad redox del resveratrol en el vino.
Los resultados obtenidos mostraron que el tebuconazol prevenía lo formación de radicales oxidantes de resveratrol, capturaba el Cu2+ y protegía los sitios de unión del resveratrol. Este efecto positivo del tebuconazol no había sido descrito previamente.