Phenolic Compound and Antioxidant Capacity Contents of Vitis labrusca. L. Genotypes

Phenolic compounds have been one of the most intensively studied topics in recent times, especially when health and healthy diet have come to the fore. There are proven health benefits of phenolic compounds found in the skin, seed, leaf and stem of grapes. While there are many studies on the phenolic content of Vitis vinifera L. species that positively contribute to human health, research on Vitis labrusca L. genotypes is far too few. In this study, total phenolic compound, antioxidant capacity and total anthocyanin levels were determined on the skin, seed, stem and leaves of the sixteen red Vitis labrusca L genotypes. In addition, the contents of the catechin, epicatechin and the trans-resveratrol, which are known to contribute to human health, were determined. According to the results of the research, the total phenolic compound content of the analyzed tissue was determined in the ranges of 115.650-5.650 mg GAE kg(-1)DW, antioxidant capacity 709-45 mu mol trolox g(-1) DW, total anthocyanin 32.788-2.037 mg kg(-1), catechin 13.131-0 mg(-1) DW, epicatechin 5.080-0 mg(-1) DW and trans-resveratrol 98-0 mg kg(-1) DW. The highest total phenolic compound content was determined in the stem of cluster of Steuben variety, the highest antioxidant capacity in the seed of Champbell Early genotype and the highest total anthocyanin in the skin of Vailant variety. The level of trans-resveratrol, which is known for its beneficial effects, is also measured at the highest in the leaves of Steuben variety as 98 mg kg(-1) DW. The Vitis labrusca species is the only species that is resistant to the humid climate of the Black Sea region, however these genotypes are not preferred for table consumption. It is believed that the skin, seed, stem and leaves of Vitis labrusca can be used as new natural antioxidant sources and thus provide significant economic benefits.