Chapter 23 - Ethyl Lauroyl Arginate (LAE): Antimicrobial Activity and Applications in Food Systems

Abstract

The use of ethyl lauroyl arginate (LAE) as an antimicrobial and food preservative is currently approved by the Food and Drug Administration (FDA) and the European Food Safety Agency (EFSA), respectively. Due to this fact, in recent years, there has been a great focus on the possible application of this compound to food systems. In this chapter, although an overview on LAE synthesis, properties, stability, metabolism, and toxicity is provided, a special emphasis is given to this compound’s antimicrobial activity and mode of action, as well as its application in food systems. LAE is a fairly stable compound with low reactivity that is synthesized through esterification and condensation steps. The vast amount of in vitro and in vivo toxicological studies demonstrates that LAE has low toxicity, possibly due to the fact that this compound is readily hydrolyzed by chemical and metabolic pathways. LAE is effective as a food preservative, due to its strong antimicrobial activity against a wide range of microorganisms, including molds, yeasts, gram-positive, and gram-negative bacteria. Values as low as 8mg/kg are able to cause microbial growth inhibition. In vitro antimicrobial susceptibility testing demonstrated that LAE has a bactericidal activity against major foodborne pathogens, being able to cause microbial death in less than 1h. Being a cationic surfactant, the main target for LAE antimicrobial action is the cell envelope, as many microscopic and flow cytometric studies have demonstrated. Despite these encouraging in vitro results, LAE possesses a much lower activity when used in real food products, as it needs to be in direct contact with the food to exert its action. So far, several strategies to use LAE as a food preservative have been proposed. Most of them deal with LAE direct addition to the food product by mixing with food or by food surface treatment, or incorporation into food packaging. Although most applications mention the use of LAE alone, some combination treatments between LAE and other preservation methods were also exploited in order to further increase the shelf life of the food product.