Department of Food Science, University of Massachusetts, Amherst, Massachusetts 01003, USA.
J Agric Food Chem. 2010 Sep 8;58(17):9770-7. doi: 10.1021/jf101309h.
Lauric arginate (LAE) is a food-grade cationic surfactant that is a highly potent antimicrobial active against a wide range of food pathogens and spoilage organisms. In compositionally complex environments, the antimicrobial activity of cationic LAE is likely to be impacted by its interactions with other charged components. The purpose of this study was to characterize the interactions between cationic LAE and various food grade biopolymers with different charge characteristics: anionic (pectin, alginate, carrageenan, xanthan), neutral (dextran), and cationic (chitosan). Isothermal titration calorimetry (ITC) and turbidity measurements were used to characterize surfactant-biopolymer interactions and the solubility of any aggregates formed. ITC and turbidity measurements suggested that no complex formation occurred between the cationic LAE and the cationic or neutral biopolymers, although the critical micelle concentration (cmc) of the surfactant was changed because of excluded volume effects. On the other hand, ITC measurements indicated a strong binding interaction between cationic LAE and anionic biopolymers. The amount of surfactant bound and the solubility of the aggregates formed depended strongly on biopolymer type. The results of this study have important implications for the application of LAE in compositionally complex systems.
月桂酰精氨酸乙酯（LAE）是一种食品级阳离子表面活性剂，对多种食源性致病菌和腐败菌具有很强的抗菌活性。在组成复杂的环境中，阳离子 LAE 的抗菌活性可能会受到其与其他带电成分相互作用的影响。本研究的目的是表征阳离子 LAE 与具有不同电荷特性的各种食品级生物聚合物之间的相互作用：阴离子（果胶、藻酸盐、卡拉胶、黄原胶）、中性（葡聚糖）和阳离子（壳聚糖）。等温热力学滴定（ITC）和浊度测量用于表征表面活性剂-生物聚合物相互作用以及形成的任何聚集体的溶解度。ITC 和浊度测量表明，阳离子 LAE 与阳离子或中性生物聚合物之间未发生复杂形成，尽管由于排除体积效应，表面活性剂的临界胶束浓度（cmc）发生了变化。另一方面，ITC 测量表明阳离子 LAE 与阴离子生物聚合物之间存在强烈的结合相互作用。结合的表面活性剂量和形成的聚集体的溶解度强烈依赖于生物聚合物的类型。这项研究的结果对 LAE 在成分复杂的系统中的应用具有重要意义。
