Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

Comparison of Total Antioxidant Capacities and Principal Components With Antioxidant Capabilities of Some Plum Varieties Cultivated İn Turkey.

Phenolic compounds (polyphenols) prevent many diseases (especially cancer, coronary & cardiovascular diseases) as great risks for human health and are abundantly present many plants. As a result of this effect on human health, phenolic compounds are named as biologically active compounds and subjected of many studies. One of the most important properties of these compounds is antioxidant activity due to scavenge of free radicals produced with metabolic reactions. Meanwhile these compounds present in fruits, vegetables and many other plant varieties are responsible for their colour, flavour and taste, as well as their food quality.

Aim of this study is to compare of total antioxidant capacities and principal antioxidant components of some plum varieties cultivated in Turkey, qualitatively and quantitatively. Because plum is an abundantly consumed fruit as fresh and dried owing to a presence in major time of year, relatively cheap and tasty fruit for many people.

Total antioxidant capacities (TAC) will be measured with the CUPRAC (cupric ion reducing antioxidant capacity) method which is a simple and low-cost assay that has reported the results as trolox equivalent antioxidant capacities (TEAC values) in many published literature, using the copper(II)-neocuproine (2,9-dimethyl-1,10-phenanthroline) reagent previously used for assaying some important reducing agents. The TAC results obtained with CUPRAC have been compared to those found by decolorization assay of radical cation ABTS (2-2’-azino-bis-(3-ethylbenzthiazoline-6sulfonic acid) generated with persulfate. The individual antioxidant compounds has been identified and quantified by HPLC (high performance liquid chromatography).

TAC results of plums studied were as Italyan > Mürdüm > Can and Italyan >Mürdüm Can according to CUPRAC and ABTS methods, respectively. Small difference at the order is resulted from differences of TEAC values of various flavonoids by both methods. TAC results calculated from individual constituents quantified HPLC with combined HPLC-spectrophotometric methods. Main reason of this case is unidentified constituents due to the lack of standard materials.

BAKİ Sefa

Danışman : Prof. Dr. Reşat APAK

Anabilim Dalı : Kimya

Programı : Analitik Kimya

Mezuniyet Yılı : 2009

Tez Savunma Jürisi : Prof. Dr. Reşat APAK

Prof. Dr. Esma TÜTEM

Prof. Dr. İzzet TOR

Prof. Dr. Hayati FİLİK

Prof. Dr. Birsen DEMİRATA ÖZTÜRK