engleski

Influence of ampelotechnical procedures in vineyard on vasodilatory effects of wine

Introduction: Partial defoliation and solarization are common ampelotechnical practices in vineyards in order to improve oenological quality of grape and wine. However, studies on biological effects of such modified wines are lacking. In this study we analyzed and compared biochemical properties and related vasodilatory effects of red wine obtained from grapevine grown in standard way and grapevine subjected to the mentioned ampelotechnical procedures. Materials and methods: Red wine, “Rota standard”, variety Plavac mali, vintage 2009, was obtained form Pelješac, Croatia. Total phenolic content (expressed in mg/L gallic acid equivalents (GAE)), phenolic fractions and antioxidant capacity (AOC, expressed in mmol/L Trolox equivalents (TE)) of the tested wines were determined spectrofotometrically. Ethanol was measured by gas chromatography. Isolated rat (n=15) and guinea pigs (n=15) aortic rings were placed into organ baths containing oxygenated Krebs- Henseleit solution. After stabilisation and evaluation of endothelial functionality, the vascular rings were precontracted with norepinephrine. Direct vasodilatory effects of wine were examined by applying cumulative doses of wine in the range of 0.5 - 8:1000 (final dilutions in organ baths). Results: “Ampelotechnical” wine had higher total phenolics content and related AOC in comparison to the control wine (4438.69 vs. 2608.71 mg/L GAE and 16.38 vs. 9.33 mmol/L TE for total phenols and AOC, respectively), while ethanol content did not differ between wines (15.06 vs. 15.19 % v/v). Both wines induced similar maximal relaxation in both animal species (80.472 vs. 83.040 for rats and 140.232 vs. 145.050 for guinea pigs, for control and “ampelotechnical” wine, respectively). However, ”ampelotechnical” wine proved to be more potent as it caused greater vasodilation at lower concentrations (0.5-2‰). Conclusions: Ampelotechnical procedures in vineyards significantly influence biological and oenological properties of the resulting wine. This in turn may enhance potentially beneficial biological effects of wine, such as vasodilation.

guinea pig; rat; vasodilation; red wine; ampelotechnical practices

nije evidentirano