Relations between polyphenols content and antioxidant activity in vine grapes and leaves

Abstract

The occurrence and content of some polyphenols and the antioxidant activity of compounds present in grape berries, stems and leaves of <i>Vitis vinifera</i> L. were evaluated. Three white and three blue varieties of grapevine were investigated. The contents were determined of <i>trans</i>-resveratrol, <i>trans</i>-piceid, caftaric acid, tryptophan, catechin, epicatechin, total polyphenols, and flavanols, both in healthy material and in the samples of the plant material infested with microorganisms (<i>Botryotinia fuckeliana</i> Whetzel anamorph <i>Botrytis cinerea</i> Pers.; Uncinula necator (Schw.) Burr; <i>Plasmopara viticola</i> (Berk. & M.A. Curtis) Berl & De Toni). The antioxidant activity of the extracts obtained was determined by different methods: FRAP (Ferric Reducing Antioxidant Power), DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and TAC-PCL (Total Antioxidant Capacity of Photochemiluminescence). The content of <i>trans</i>-resveratrol varied between 0.3–2.3 mg/kg and 0.7–12.1 mg/kg in non-infested and infested grape berries, respectively. The content of <i>trans</i>-piceid between 0.6–2.9 mg/kg and 1.5–6.3 mg/kg in non-infested and infested grape berries, respectively. The content of trans-resveratrol varied between 2.5–10.3 mg/kg and 3.7–20.9 mg/kg in healthy and in infected leaves, respectively. The content <i>trans</i>-piceid varied between 11.3–58.4 mg/kg and 18.5–60.9 mg/kg in the healthy and in the infected leaves, respectively. The highest content of trans-resveratrol was found in stems (16.3–276.3 mg/kg). In young lateral shoots, the highest levels of <i>trans</i>-piceid (12.6–99.7 mg/kg) and caftaric acid (474–2257 mg/kg) were determined. The infested grape berries showed a higher antioxidant activity, which was most closely correlated with the content of total polyphenols (correlation coefficient = 0.8336–0.9952).

Characterization of an Antioxidant-Enriched Beverage from Grape Musts and Extracts of Winery and Grapevine By-Products

“…The presence of these compounds was in agreement with previous reports identifying caftaric acid, epicatechin, and quercetin and malvidin derivatives as the main metabolites concerning grape stems [40,41]. Although the presence of stilbenes in grape canes has been reported previously [42][43][44], these compounds were not detected in this study. The absence of stilbenoids in grapevine extracts can be attributed to the use of polar aqueous extraction conditions and the lack of UV-C irradiation in grapevines, as the biosynthesis of resveratrol in grape leaves is strongly increased in response to UV-C irradiation [45], or the storage at −20 • C of grapevine canes after collection.…”

Evaluation of five protocols for DNA extraction from leaves of Malus sieversii, Vitis vinifera, and Armeniaca vulgaris

“…The DNA extracted from canes and dried leaves were of good quality in all five protocols (Figure 1). In the grapevine samples, all five methods produced better quality DNA from green canes compared to fresh leaves, which was perhaps due to the relatively low content of secondary metabolites and high levels of antioxidants in canes (Balik et al, 2008). However, in most protocols, the concentration of DNA extracted from canes was lower than that obtained from dried leaves ( Table 1).…”

Relations between downy/powdery mildew diseases andsome phenolic compounds in Vitis spp.

“…For the evaluation of the antioxidant activity of vine grapes and wines, several methods were used (Fernández-Pachón et al, 2006;Stratil et al, 2008). Balik et al (2008) reported that grape berries infected by fungal disease showed a higher antioxidant activity, which was most closely correlated with the content of total polyphenols (correlation coefficient = 0.8336-0.9952). Downy mildew, caused by Plasmopara viticola (Berk.…”