Determination of Bioactive Compounds and Mineral Contents of Seedless Parts and Seeds of Grapes

Abstract

In this study, phenolic compounds, minerals, total flavonoids, total phenolic contents and antioxidant activities of the seedless parts (pulp+skin) and seeds of table and wine grapes were determined. Also, the total oil, tocopherol contents and fatty acid composition of seed oils of table and wine grapes were investigated. The highest total phenolic content of the grape pulp was found in Trakya ilkeren (199.063 mg/100 g), while total flavonoid and antioxidant activity of the pulp was determined at a high level in Red Globe (6.810 mg/g, 90.948%). Antioxidant activity, and the total phenolic and flavonoid contents of grape seeds varied between 86.688 and 90.974%, 421.563 and 490.625 mg GAE/100 g, and 90.595 and 145.595 mg/g respectively (p < 0.05). Generally, the main phenolic compounds of all grape pulps and seeds were gallic acid, 3,4-dihydroxybenzoic acid, (+)-catechin and 1,2-dihydroxybenzene. In addition, the oil contents of grape seeds ranged from 5.275 (Çavuş) to 13.881% (Çınarlı karası) (p < 0.05). The major fatty acids of grape seed oils were linoleic, oleic and palmitic acid. The seed oil of the Trakya ilkeren variety was rich in tocopherols in comparison with the other varieties. The major minerals of both the seedless parts and the seeds were determined as K, Ca, P, S, Mg.

Content and bioavailability of trace elements and nutrients in grape pomace

“…The values obtained for Ca and Mg were considerably lower than those found for K in all samples. In contrast, other authors found higher K and Ca content with respect to Mg in the grape seeds of different grape varieties from Turkey . The Ca content was between 3.16 and 4.05 mg g −1 for skins (Table ) and between 2.41 and 4.70 mg g −1 for seeds (Table ), with relatively similar values in all of the varieties that were studied, although Godello samples showed significantly lower content in seeds ( P < 0.001).…”

“…Regarding the distribution of metals between skins and seeds within each variety (Tables and ), in general the total metal content in seeds was lower than in skins for all the elements, except for Ca and Mg in most samples. In contrast, other authors reported that the mineral content of grape seeds was higher than that found in other parts of the grape . In the case of Zn, the total content in seeds was slightly higher than that obtained in skins for most samples, except for Treixadura and Sousón varieties where the content in skins was between 1.2 and 1.6 times greater.…”

“…Regarding micronutrients, Cu and Fe were the most abundant elements in skins (Table ) and Fe was the most abundant element in seeds (Table ). Higher Fe content was also found than other micronutrients in grape seeds of Turkish grape varieties . Total Fe content ranged from 123 to 355 μg g −1 in skins (Table ) and from 89.1 to 230 μg g −1 in seeds (Table ), corresponding the significantly higher contents corresponding to the Godello white variety (except in distilled seeds) (P < 0.001) compared to the other samples.…”

“…In contrast, other authors found higher K and Ca content with respect to Mg in the grape seeds of different grape varieties from Turkey. 22,23 The Ca content was between 3.16 and 4.05 mg g −1 for skins (Table 1) and between 2.41 and 4.70 mg g −1 for seeds (Table 2), with relatively similar values in all of the varieties that were studied, although Godello samples showed significantly lower content in seeds (P < 0.001). The Mg content was always lower than 1.73 mg g −1 for both skins and seeds (Tables 1 and 2) and, in contrast to K, the values in skins for red varieties (Sousón and Mencía) were significantly lower than those obtained for white varieties (P < 0.001).…”

Effect of varieties on bioactive compounds, fatty acids, and mineral contents in different grape seed and oils from Bosnia and Herzegovina

“…Grape ( Vitis vinifera L.) ranks among most important commercial fruit crops being grown and utilized around the globe since long (Al Juhaimi & Özcan, in press; Bail et al, ; Hussein & Abdrabba, ). The oil from grape seed is now becoming popular as a culinary oil due to the presence of specialty lipids and it may also serve as a good source of other nutritionally beneficial phytochemicals including phenol compounds, tocopherols, and fatty acids (Bail et al, 2008; Bjelica et al, ; Lutterodt, Slavin, Whent, Turner, & Yu, ; Geçgel et al, ; Ovcharova et al, ; Özcan, Al Juhaimi, Gülcü, Uslu, & Geçgel, ; Radovanovic, Dekic, & Radovanovic, ; Vujovic, Pejin, Popovic Djordjevic, Velickovic, & Tesevic, ). According to Wijendran and Hayes () and Beveridge, Girard, Kopp, and Drover (), oil from grape seeds contain unsaturated fatty acids, particularly oleic, and linoleic acids, which have been established to play vital role in cardiovascular health of humans.…”