Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye
Tezin Onay Tarihi: 2006
Tezin Dili: İngilizce
Öğrenci: Işıl Narlı
Danışman: LEVENT KAMİL TOPPARE
Özet:Immobilization of tyrosinase enzyme was performed in the matrices obtained via copolymerization of terephthalic acid bis-(2-thiophen-3-yl ethyl) ester (TATE) with pyrrole. During electrochemical polymerization of pyrrole, enzyme molecules were entrapped in the copolymer matrice. Activity measurements were performed by using Besthorn̕s Hydrazone method which includes spectrophotometric analysis of quinones produced by the enzyme. Enzyme electrodes were characterized in terms of maximum reaction rate (Vmax) and Michaelis-Menten constant (Km). In addition to kinetic parameters, stability of enzyme electrodes towards environmental conditions such as pH and temperature was investigated. Usage stability and shelf-life analysis were also examined. Wines, especially red wines, contain numerous biologically active compounds, the most important of which are polyphenols, whose nutritional importance is attributed to their antioxidant power. The amounts of phenolic compounds in different red wines were analyzed by using obtained enzyme electrodes. The phenolic compound determination using free enzyme cannot reflect the actual values since there are also naturally found inhibitors in red wines. Benzoic acid, cinnamic acid and sorbic acid were utilized to understand the behavior of immobilized tyrosinase in the conducting polymer matrices toward inhibition.