Bu çalışmada, Bartın ilinin Serdar Köyü mevkiinde doğal olarak yetişen İzabella Üzümü (Vitis labrusca L.) meyveleri taze halde, dış ortamda kurutulmuş ve etüvde kurutulmuş olmak üzere 3 farklı örnek kullanılmıştır. İzabella Üzümü (Vitis labrusca L.) 'nün fenolik bileşenleri HPLC yöntemiyle belirlenmiştir. Toplam Fenolik Madde Miktarı tayini Folin-Ciocalteu Ayıracı (FCR) ile tespit edilmiştir. V. labrusca bitkisinin antioksidan özellikleri DPPH Serbest Radikali Giderim Aktivitesi Yöntemi uygulanarak belirlenmiştir. Dış ortamda kurutulan V. labrusca meyvesine ait fenolik bileşen analizi sonucunda p-hidroksibenzoik asit (1.133 mg/L), benzoik asit (0.571 mg/L), protokateşik asit (0.323 mg/L), gallik asit (1.343 mg/L), rosmarinik asit (1.065 mg/L), siringaldehit (0.272 mg/L), trans-Ferulik asit (1.222 mg/L) ve vitamin C (15.191 mg/L) fenolik bileşenler tespit edilmiştir. Etüvde kurutulan V. labrusca meyvesine ait fenolik bileşen analizi sonucunda p-Hidroksibenzoik asit (1.161 mg/L), benzoik asit (0.353 mg/L), protokateşik asit (0.231 mg/L), gallik asit (1.102 mg/L), rosmarinik asit (1.062 mg/L), siringaldehit (0.253 mg/L), trans-Ferulik asit (1.382 mg/L), kateşin (1.532 mg/L) ve vitamin C (15.160 mg/L) fenolik bileşenler tespit edilmiştir. Taze haldeki V. labrusca meyvesine ait fenolik bileşen analizi sonucunda p-Hidroksibenzoik asit (0.006 mg/L), benzoik asit (0.329 mg/L), protokateşik asit (0.239 mg/L), gallik asit (1.002 mg/L), rosmarinik asit (1.054 mg/L), siringaldehit (0.250 mg/L), trans-Ferulik asit (1.243 mg/L) ve vitamin C (11.205 mg/L) olarak tespit edilmiştir. V. labrusca ekstresinde yapılan analizler sonucunda en yüksek resveratrol miktarı taze halde (1.625 mg/L), en düşük resveratrol miktarı etüvde kurutulan örneklerde (0.289 mg/L) tespit edilmiştir. Gallik asit eşdeğer alınarak Folin-Ciocalteu yöntemi kullanılarak yapılan çalışmada toplam fenolik madde miktarı en yüksek 62.686 ± 8.26 mg GAE/g olarak etüvde kurutulan meyvelerde, en düşük 34.781 ± 0.73 mg GAE/g olarak taze haldeki meyvelerde tespit edilmiştir. Antioksidan yüzde inhibisyon değerleri; Dış ortamda kurutulan örneklere ait 50 µg/ml'de %40.98, 100 µg/ml'de % 47.52, 250 µg/ml'de %49.41, 500 µg/ml'de % 50.58 ve 1000 µg/ml'de % 51.74 olarak tespit edilmiştir. Etüvde kurutulan örneklere ait 50 µg/ml'de % 45.05, 100 µg/ml'de % 53.48, 250 µg/ml'de %55.23, 500 µg/ml'de %56.10 ve 1000 µg/ml'de % 56.83 olarak tespit edilmiştir. Taze haldeki örneklere ait 50 µg/ml'de %51.30, 100 µg/ml'de % 57.84, 250 µg/ml'de %60.17, 500 µg/ml'de %61.48 ve 1000 µg/ml'de % 62.93 olarak tespit edilmiştir. Bu çalışmada sonuç olarak; İzabella Üzümü (Vitis labrusca L.)'nün fenolik bileşenleri ve antioksidan özellikleri belirlenmiş olup, sağlık alanında (tıp, eczacılık vb.) kullanımının artırılması hedeflenmiştir. V. labrusca Türkiye ekonomisine katkı sağlama potansiyeli olan ve ticari yetiştiriciliği yapılması gereken bir türdür. In this study, three different samples, fresh, oven dried and air dried Isabel grape (Vitis labrusca L.) growing naturally in Serdar village of Bartin province were used. The phenolic compounds of Isabel grape (Vitis labrusca L.) were determined using HPLC method. Total phenol content determination has been identified with Folin-Ciocalteu Reagent (FCR). Antioxidant properties of V. labrusca were determined through free radical scavenging Removal Activity. As a result of phenolic compound analysis of air dried Isabel grape (Vitis labrusca L.) fruit samples, p-hdroxybenzoic acid (1.133 mg/L), benzoic acid (0.571 mg/L), protocatechuic acid (0.323 mg/L), Gallic acid (1.343 mg/L), rosmarinic acid (1.065 mg/L), siring aldehyde (0.272 mg/L), trans-Ferulic acid (1.222 mg/L) and vitamin C (15.191 mg/L) phenolic compounds were found. And as a result of phenolic compound analysis of oven dried Isabel grape (Vitis labrusca L.) fruit sample,p- hdroxybenzoic acid (1.161 mg/L), benzoic acid (0.353 mg/L), protocatechuic acid (0.231 mg/L), gallic acid (1.102 mg/L), rosmarinic acid (1.062 mg/L), siring aldehyde (0.253 mg/L), trans-Ferulic acid (1.382 mg/L), catechin (1.532 mg/L) and vitamin C (15.160 mg/L) phenolic compounds were identified. And as a result of phenolic compound analysis of fresh Isabel grape (Vitis labrusca L.) fruit samples,p- hdroxybenzoic acid (0.006 mg/L), benzoic acid (0.329 mg/L), protocatechuic acid (0.239 mg/L), gallic acid (1.002 mg/L), rosmarinic acid (1.054 mg/L), siring aldehyde (0.250 mg/L), trans-Ferulic acid (1.243 mg/L) and vitamin C (11.205 mg/L) phenolic compounds were found. As a result of analyses in V. labrusca extract, highest amount of resveratrol was found in fresh samples (1.625 mg/L), whilst the lowest amounts of resveratrol was found in oven dried V. labrusca samples (0.289 mg/L). The highest amount of total phenolic compound was found in oven dired fruit samples (62.686 ± 8.26 mg GAE/g) , while the lowest amount of total phenolic compounds was found in fresh fruit samples (34.781 ± 0.73 mg GAE/g)in this study which was carried out using Folin-Ciocalteu method (gallic acid equivalent). Antioxidant % inhibition amounts of air dry grape samples in 50 µg/ml-%40.98, in 100 µg/ml-% 47.52, in 250 µg/ml-%49.41, in 500 µg/ml-% 50.58 and in 1000 µg/ml-% 51.74 were determined. Oven dry grape samples antioxidant % inhibition amounts in 50 µg/ml-% 45.05, in 100 µg/ml-% 53.48, in 250 µg/ml-%55.23, in 500 µg/ml-%56.10 and in 1000 µg/ml-% 56.83 were determined. Antioxidant % inhibition amounts were found as 40.98% in 50 µg/ml in air dried samples; 47.52% in 100 µg/ml, and 49.41% in 250 µg/ml, 50.58% in 500 µg/ml and % 51.74% in 1000 µg/ml. And the same amounts for oven dried samples were % 45.05 in 50 µg/ml, 53.48% in 100 µg/ml, 55.23% in 250 µg/ml, 56.10% in 500 µg/ml and 56.83% in 1000 µg/ml; while it was 51.30% in 50 µg/ml, % 57.84 in 100 µg/ml, %60.17 in 250 µg/ml, %61.48 in 500 µg/ml and % 62.93 in 1000 µg/ml in fresh fruit samples. As a result, phenolic compounds and antioxidant properties of Isabel grape (Vitis labrusca L.) were determined in the current study and the aim of doing that to increase the use of the fruit in health (medicine, pharmacy, etc.). V. labrusca is a fruit which has a potential to contribute to Turkey's economy and is a plant that needs to be grown as a commercial product. 84