ANTIMICROBIAL ACTIVITY OF ESSENTIAL OILS AGAINST FOODBORNE PATHOGENS ISOLATED FROM DAIRY PRODUCTIVE CHAIN
The increase on the demand for healthy foods, associated with the increase of bacterial resistence to antibiotics and conventional antimicrobial compounds has directioned the food industry to the replacement of this compounds by natural additives with the same antimicrobial and antioxidant functions. The aim of this study was to evaluate the essential oils (OE) antimicrobial activity of Rosmarinus officinalis, Cymbopogon citratus, Cymbopogon nardus, Piper nigrum, Mentha piperita, Cymbopogon martinii, Vetiveria zizanioides, Pogostemon cablin, Eucalyptus citriodora and Eucalyptus globulus against pathogens isolated from dairy productive chain. For this study were used strains of Staphylococcus aureus (3), Escherichia coli (3) and Salmonella spp. (1) isolated from enviromental or dairy product contamination. The evaluation of the essential oils antimicrobial activity was performed by the method of Minimal Inhibitory Concentration (MIC) on concentrations betweeen 10 and 0,0048%. The most effective essential oils on the inhibition of Staphylococcus aureus and Escherichia coli were the ones provided from the species Cymbopogon citratus (Lemon grass), with MIC of 1,13±1,25mg/ml and 1,23±0,30mg/ml, respectively, and Cymbopogon martinii (Palmarosa), with MIC of 1,16±0,95mg/ml and 1,36±2,35x10-16mg/ml. For the inhibition of Salmonella spp. the most effective essential oils were Cymbopogon martinii (Palmarosa) and Mentha piperita (Peppermint) with MIC 0,51±0,29mg/ml and 1,86±0,81mg/ml, respectively. The obtained results demonstrate that even in low concentrations the essential oils of Lemon grass, Palmarosa and Peppermint are satisfactory alternatives to the replacement of conventional antimicrobial compounds. Among the major aplications, some essential oils can be used on food formulations as a result of been considered GRAS (Generally Recognized as Safe), on sanitizers or incorpored to polymeric matrixes for the production of antimicrobial active packaging, what can provide to the producer industry better competitiveness due the approach of health promotion and better food safety.