FSHW:金屬離子與槲皮素相互作用的研究

   

槲皮素(3,3’,4’,5,7-五羟基黃酮)是含量豐富的黃酮類化合物之一,主要存在于藥用植物、水果、樹葉和蔬菜中。它顯示了帶I吸收(300~380nm),這被認為是與B環肉桂酰體系有關,帶II吸收(240~280nm)與A環苯甲酰體系有關。由于槲皮素結構中存在螯合位點,它能夠與一系列陽離子形成複合物,這些陽離子具有抗氧化活性、DNA保護、抗腫瘤和抗癌活性以及抗炎作用。

巴西巴拉那聯邦研究所的Taiane Souza de Castilho、Tatiane Brescovites Matias、Keller Paulo Nicolini等人基于黃酮類槲皮素和過量金屬氯化物之間的相互作用的置換試驗可以得到槲皮素和Ca

2+

、Mg

2+

和Ni

2+

之間反應的結合常數。得到的值為Ca

2+

為2.20±1.77×10

3

,Mg

2+

為1.37±0.59×10

3

,Ni

2+

為7.03±1.04×10

4

,經滴定和連續變化法測定,所有相互作用均為1:1化學計量比(Job法)。通過培養基中的比色變化(黃→氖黃),定性地觀察絡合結果,并通過金屬存在條件下槲皮素吸收帶的深色位移進行光譜學觀察。這項研究為開發和測試通過構建有效的生物有機系統從而能夠捕獲有毒金屬離子或有利于吸收有益離子(與人類新陳代謝有關)的材料提供了工具。研究結果表明結合常數的遞升次序:Mg

2+

2+

3+
2+

文章摘要

ABSTRACT

Study of interaction between metal ions and quercetin

Taiane Souza de Castilho, Tatiane Brescovites Matias, Keller Paulo Nicolini,  JaquelineNicolini

Instituto Federal do Paraná – IFPR, Lacoppi – Laboratório de Corantes e Processos Pirolíticos, Departamento de Química, Palmas, PR, Brazil

Abstract

A displacement test based on the interaction between the flavonoid quercetin and an excess of metal chloride allows the determination of the binding constant for the reaction between quercetin and Ca

2+

, Mg

2+

 and Ni

2+

. The values obtained were 2.20 ± 1.77 ×10

3

 for Ca

2+

, 1.37 ± 0.59 × 10

3

 for Mg

2+

 and 7.03 ± 1.04 × 10

4

for Ni

2+

, and all interactions showed type 1:1 stoichiometry, as determined by titration and by the method of continuous variations (Job’s method). The complexion effect was observed qualitatively through a colorimetric change in the medium (yellow → neon yellow) and spectroscopically through a bathochromic shift in the absorption band of quercetin in the presence of metals. This investigation serves as a tool for the development and testing of materials capable of capturing toxic metal ions or favoring the absorption of beneficial ions (in relation to the human metabolism) through the construction of efficient bioorganic systems. The results reported herein allow understanding of this detection system, indicating the following ascending order of the binding constants (