YEŞİL ÇAY VE SİYAH ÇAY EKSTRELERİNDEKİ GALLİK ASİT, EGCG İÇERİĞİ VE ANTİRADİKAL AKTİVİTESİNİN DEĞERLENDİRİLMESİ

Öz

Amaç: Çay, dünyada çok iyi bilinen ve tüketilen bir içecek olup antioksidan aktivitesine bağlı koruyucu etkileri bilinen önemli bir fitobesindir. Bu çalışmanın amacı, Kuzey Anadolu kaynaklı Camellia sinensis bitkisinden elde edilen yeşil çay ve siyah çaydan hareketle elde edilen ekstrelerdeki gallik asit ve epigallokateşin gallat miktarı ile ekstrelerin antiradikal aktivitesinin tespit edilmesidir.

Gereç ve Yöntem: Yeşil çay ve siyah çayın etanol, metanol ve sulu ekstrelerindeki gallik asit ve epigallokateşin gallat miktar tayini YPSK yöntemi ile tespit edilmiş ve ekstrelerin antiradikal aktivite tayini için DPPH ve ABTS yöntemleri kullanılmıştır.

Sonuç ve Tartışma: Toplam 6 ekstredeki gallik asit içeriği 0.052-1.341 mg/100 ml aralığında bulunmuş ve EGCG (epigallokateşin gallat) için bu değer aralığı 0-19.54 mg/100ml olarak tespit edilmiştir. Hem DPPH hem de ABTS radikali üzerinde en iyi etkiyi yeşil çayın sulu ekstresinin sağladığı belirlenmiştir. Yeşil çayın, koruyucu sağlıkta değerlendirilebilecek iyi bir aday olduğu ancak fitobesin ve farmasötik kalitede ürünün formülasyon çalışmalarında, bitkinin hasat yöntemi, bitkiden hareketle çay üretim prosesi, optimum karıştırma zamanı, kullanılan çözücü ve yaprakların parçalanma derecesinin kayıt altına alınması gerekmektedir.

Anahtar Kelimeler

• Antiradikal aktivite,camellia sinensis,egcg,gallik asit,siyah çay,yeşil çay

Evaluation on Gallic Acid, EGCG Contents and Antiradical Activity of Green Tea and Black Tea Extracts

Öz

Objective: Tea is very well known and consumed beverage worldwide also cultivated widely. It is one of phytonutrients that has a protective role associated with its antioxidant activity. The aim of this article is to study the gallic acid, epigallocatechin gallate contents and antiradical activity of green tea and  black tea extracts from Camellia sinensis cultivated in North Anatolia.

Material and Method: Gallic acid and epigallocatechin gallate contents were investigated in ethanol, methanol and water extracts of green tea and black tea by HPLC analysis and the antiradical activities were also examined for scavenging effect on DPPH and ABTS free radicals.

Result and Discussion: In total 6 extracts, gallic acid contents were determined in the range of 0.052-1.341 mg/100 ml and the value of EGCG (epigallocatechin gallate) were found between 0-19.54 mg/100ml. Water extract of green tea exhibited the best antiradical activity on both DPPH and ABTS radicals. Green tea could be evaluated as a good candidate for health prevention but it should be noted that the harvesting method and manufacturing process, optimum conditions on brewing time, the solvent used, chopping grade of tea leaves should also be taken into consideration during formulating both phytonutrient and pharmaceutical grade products. 

Anahtar Kelimeler

• gallic acid,EGCG,antiradical activity,green tea, black tea,Camellia sinensis

Kaynakça

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