Colon Marta, Nerin Cristina
Department of Analytical Chemistry, Aragon Institute of Engineering Research I3A, CPS-University of Zaragoza , Torres Quevedo Building, Marı́a de Luna St. 3, E-50018 Zaragoza, Spain.
J Agric Food Chem. 2014 Jul 16;62(28):6777-83. doi: 10.1021/jf5011287. Epub 2014 Jul 8.
Migration of green tea components from an active packaging material containing green tea extract was performed in water and 3% acetic acid in water. The migration values for acid simulant were much higher than the values obtained in water. The influence of the acidic media in solutions of catechin standards and green tea extract was evaluated by liquid chromatography. Catechin, epicatechin, and caffeine from the green tea extract exhibited major variation in their concentrations values, with increases of 29.90, 20.75, and 15.95%, respectively, in acidic medium. The results suggested that catechins and caffeine form complexes through intermolecular interactions in neutral media and that these interactions are broken in acidic media. The continuous variation method was also performed to confirm the stoichiometry of the complexes between catechins and caffeine. Finally, a computer simulation was applied by Chem Pro 12.0, and the energies involved were calculated to confirm the experimental results obtained.
绿茶提取物活性包装材料中绿茶成分在水和3%醋酸水溶液中的迁移情况进行了研究。酸模拟物中的迁移值远高于在水中获得的值。通过液相色谱法评估了酸性介质对儿茶素标准品溶液和绿茶提取物的影响。绿茶提取物中的儿茶素、表儿茶素和咖啡因的浓度值有较大变化，在酸性介质中分别增加了29.90%、20.75%和15.95%。结果表明，儿茶素和咖啡因在中性介质中通过分子间相互作用形成复合物，而这些相互作用在酸性介质中被破坏。还采用连续变化法确定儿茶素与咖啡因之间复合物的化学计量比。最后，使用Chem Pro 12.0进行计算机模拟，并计算所涉及的能量以证实获得的实验结果。
