EVALUATION OF PLA ACTIVE BIODEGRADABLE FILMS INCORPORATED OF ESSENTIAL OILS TO INHIBIT MICROBIAL ADHESION

Abstract

An evaluation of incorporated polylactic acid (PLA) active biodegradable films of essential oils to inhibit microbial adhesion was performed using a 2V5−1 fractional exploratory design, combining the factors, amount of PEG 400 plasticizer (10 and 20 %), amount of cinnamon essential oil (0.5 % and 1 %), amount of oregano essential oil (0.5 % and 1 %), Salmonella spp. concentration (103 CFU mL−1 and 104 CFU mL−1) and Staphylococcus aureus concentration (103 CFU mL−1 and 104 CFU mL−1). The results of microbial adhesion inhibition test showed that the maximum inhibition percentage reached 73.82 ± 0.35 % corresponding to experiment 7 (bce), which contains 10 % of PEG 400, 1 % of cinnamon essential oil, 1 % of oregano essential oil, 103 CFU mL−1 of Salmonella spp. concentration, 104 CFU mL−1 of Staphylococcus aureus concentration. Statistical analysis determined that there is strong significant evidence (p − value = 0.0283) that Staphylococcus aureus concentration influences the inhibition percentage to microbial adhesion; as well as that the cinnamon essential oil- Salmonella spp. interaction has little significant evidence (p − value = 0.0711) that influences the inhibition percentage. Inhibition results greater than 60 % have the highest concentration of Staphylococcus aureus as a common factor. PLA active biodegradable films with a higher inhibition percentage can potentially be used in the food industry as a barrier mechanism to avoid bacterial contamination.