Sarpietro Maria Grazia, Caruso Sebastiana, Librando Vito, Castelli Francesco
Dipartimento di Scienze Chimiche, Università di Catania, Viale Andrea Doria 6, 95125 Catania, Italy.
Mol Nutr Food Res. 2005 Oct;49(10):944-9. doi: 10.1002/mnfr.200500072.
The protective effects of some foods, in particular fruits and vegetables, against cardiovascular disease and cancer are believed to be due to the presence of antioxidant substances such as hydroxyaromatic compounds. The aim of this work was to study (i) the interaction of three biophenols derived from benzoic acid (p-hydroxybenzoic acid, vanillic acid, syringic acid and benzoic acid) with model biomembranes and (ii) their transfer through an aqueous medium to be absorbed into a lipid bilayer, investigating the effect they exert on the thermotropic behaviour of model membranes represented by dimyristoylphosphatidylcholine multilamellar vesicles using differential scanning calorimetry. The compounds, when dispersed in liposomes during their preparation, at pH = 4, were found to modify the gel to liquid crystal phase transition of the lipid vesicles, causing a temperature shift towards lower values. The temperature shift was a function of the concentration of acids in the lipid aqueous dispersions and their lipophilic character. The kinetic experiments of compounds transfer through the aqueous medium and the absorption by the bilayer were performed contacting the antioxidant compounds (at a fixed concentration) and the model membrane at increasing incubation times. These experiments reveal that the transfer of the examined compounds through the aqueous medium and their uptake by bilayer are influenced by the presence of substituents located on the ring, which should consequently modify their lipophilicity.
一些食物，尤其是水果和蔬菜，对心血管疾病和癌症具有保护作用，据信这归因于抗氧化物质的存在，如羟基芳香化合物。这项工作的目的是研究：（i）三种源自苯甲酸的生物酚（对羟基苯甲酸、香草酸、丁香酸和苯甲酸）与模型生物膜的相互作用；（ii）它们通过水相介质转移并被吸收到脂质双层中的情况，使用差示扫描量热法研究它们对由二肉豆蔻酰磷脂酰胆碱多层囊泡代表的模型膜的热致行为的影响。在制备过程中，当这些化合物在pH = 4时分散在脂质体中时，发现它们会改变脂质囊泡从凝胶相到液晶相的转变，使温度向更低值偏移。温度偏移是脂质水分散体中酸浓度及其亲脂性的函数。通过使抗氧化化合物（固定浓度）与模型膜在增加的孵育时间下接触，进行了化合物通过水相介质转移和被双层吸收的动力学实验。这些实验表明，所研究的化合物通过水相介质的转移及其被双层的摄取受到环上取代基的影响，这相应地会改变它们的亲脂性。
