Sicari Michela, Stevanato Roberto, Ongaro Italo, Zuliani Roberto, Ravagnan Giampietro, Lucchini Vittorio
Department of Molecular Sciences and Nanosystems, University Ca' Foscari of Venice, Via Torino 155, 30170 Mestre Venice, Italy.
Department of Molecular Sciences and Nanosystems, University Ca' Foscari of Venice, Via Torino 155, 30170 Mestre Venice, Italy.
Food Chem. 2018 Jan 15;239:964-974. doi: 10.1016/j.foodchem.2017.06.139. Epub 2017 Jun 28.
The inhibition properties of a number of antioxidants against peroxidation, started by a 2,2'-azobis[2-(2-imidazolin-2-yl)propane] radical initiator, of linoleic acid in sodium dodecyl sulfate micelles, have been determined in terms of oxygen consumption by a Clark electrode in an oxygen-tight cell. For the 31 antioxidants investigated at variable concentrations, the experimental results well fit the kinetic equation for competitive reactions. The ratio between the initial rates, monitored in the absence and in the presence of antioxidants, depends linearly on their concentration. From the slopes of these straight lines, an absolute scale of inhibition properties of the lipid peroxidation can be devised. Furthermore, the little difference of the time of complete oxygen consumption on concentration of different antioxidants has been found, indicating a restricted difference towards chemical structure and stoichiometric ratio. Some considerations regarding the mechanisms of inhibition of the lipid peroxidation in micelles, in view of bibliographic data, have been made.
在密封的氧电极电池中，通过Clark电极测定耗氧量，确定了多种抗氧化剂对由2,2'-偶氮二[2-(2-咪唑啉-2-基)丙烷]自由基引发剂引发的、十二烷基硫酸钠胶束中亚油酸过氧化反应的抑制特性。对于在不同浓度下研究的31种抗氧化剂，实验结果很好地符合竞争反应的动力学方程。在不存在和存在抗氧化剂的情况下监测的初始速率之比，与它们的浓度呈线性关系。根据这些直线的斜率，可以设计出脂质过氧化抑制特性的绝对标度。此外，还发现不同抗氧化剂浓度下完全耗氧时间的差异很小，这表明在化学结构和化学计量比方面的差异有限。鉴于文献数据，对胶束中脂质过氧化抑制机制进行了一些思考。
