Trans-resveratrol extraction from grapevine: Application to berries and leaves from vines affected by esca proper

摘要

Trans-resveratrol is a metabolite involved in resistance of plants during biotic and abiotic stress. Here we report the optimization of a rapid solvent extraction protocol and its application to different parts of grapevines. We also demonstrate the influence of sample pretreatment with liquid nitrogen on trans-resveratrol stability, which results as the key step in avoiding oxygen degradation during solvent extraction. Up to 94% of trans-resveratrol was recovered using this procedure. Berries and leaves from healthy and symptomatic, esca proper-affected vines collected at two different phenological growth stages were analyzed. Trans-resveratrol was determined in berry and leaf samples; symptomatic vines always showed a significantly higher amount with respect to healthy vines. The mean concentration of trans-resveratrol in berries was 0.93 mu g/g(dm) and 1.92 mu g/g(dm) at veraison and 1.49 mu g/g(dm) and 2.72 mu g/g(dm) at harvest from healthy and symptomatic vines, respectively.