Characterization and application of Lippia alba (Mill) and Cymbopogon citratus D.C. Stapf. essential oils as natural sanitizers in coriander

Abstract Essential oils (EOs) are a promising alternative for food preservation and can be used instead of synthetic antimicrobial compounds such as sanitizers, as long as they are efficient and safe. In view of this possibility of use, Lippia alba (Mill) (LAEO) and Cymbopogon citratus D.C. Stapf. (CCEO) essential oils were evaluated as natural antimicrobials and applied into coriander for its biocontrol. The EOs were extracted and their physical properties, total phenolics, cytotoxicity to Artemia salina L. and antimicrobial potential in vitro and on natural coriander microbiota were determined. The EOs had a LD50 (median lethal dose - checked), are considered biologically active. MIC (Minimum Inhibitory Concentration) varied from 1.25 to 5.00 μL/ mL and from 0.62 to 5.00 μL/ mL for LAEO and CCEO, respectively, on standard strains of Staphylococcus aureus, Salmonella Thyphimurium, Salmonella Enteritidis, Escherichia coli and Listeria monocytogenes. The lowest MIC values for LAEO and CCEO were selected for application in coriander. EOs reduced the pathogenic microbial load in the coriander revealing its potential as a natural sanitizer, and thus demonstrating superior or equivalent efficacy to commercial sanitizer. By correlating the cytotoxic and antimicrobial results obtained, we have shown that these EOs present potential for application in foods.