THEORETICAL INVESTIGATION OF CERTAIN TEA COMPOUNDS IN AQUEOUS AND BLOOD PHASES

Yıl 2012, Cilt: 2 Sayı: 1, 45 - 62, 21.05.2012

Ülkü Dilek Uysal , Halil Berber , Elif Mine Öncü Kaya

Öz

In this study, certain theoretical properties of tea compounds, such as acidity constant, stability, reactivity, geometry and energy have been calculated prior to laboratory studies to understand the basic principles concerning their behaviors within the human body by MOPAC2009 with the PM6 method. The order of proton dissociation, dipole moment and nucleophilicity for the studied molecules in aqueous and blood phases were investigated. The order of stabilities of the molecules was determined in relation to the Gibbs free energy. It is observed that any molecule having more of the -OH group has more stability and is less reactive. The stabilities of all the molecules are higher in the aqueous phase than those in the blood phase. Their calculated acidity constants were compared with those of experimental values. Positive meaningful correlations (R²> 0.9999) were observed between thermokinetic pKa values for 1c, 2ec, 3cg, 4ecg, 5egc, 6egcg and 7ga in both aqueous and blood phases.

Anahtar Kelimeler

Catechins, Polyphenol, Tea, Theoretical calculation, PM6, Marvinbeans, Sparc

BAZI ÇAY BİLEŞENLERİNİN SU VE KAN FAZINDA TEORİK OLARAK İNCELENMESİ

Öz

Bu çalışmada, çay bileşiklerinin asitlik sabiti, kararlılık, reaktivite, geometri ve enerji gibi bazı teorik özellikleri, laboratuvar çalışmalarından önce insan vücudundaki davranışlarının temel prensiplerini anlamak için, MOPAC 2009 (PM6 metodu) ile hesaplanmıştır. Çalışılan bileşiklerin proton verme sıraları, dipol momentleri ve nükleofillikleri su ve kan fazında araştırılmıştır. Moleküllerin kararlılık sıralamaları Gibbs serbest enerjileri dikkate alınarak belirlenmiştir. Daha fazla –OH grubu içeren molekülün daha kararlı ve daha az reaktif olduğu gözlenmiştir. Bütün moleküller, su fazında kan fazına göre daha kararlıdır. Hesaplanan asitlik sabitleri deneysel sabitleriyle karşılaştırılmıştır. 1c, 2ec, 3cg, 4ecg; 5egc, 6egcg ve 7ga moleküllerinin su ve kan fazındaki termodinamik pKa değerleri arasında anlamlı bir korelasyon (R2> 0.9999) gözlenmiştir

Anahtar Kelimeler

Kateşinler, Polifenol, Çay, Teorik hesaplama, PM6, Marvinbeans, Sparc

Kaynakça

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