Multivariate Study of the Effects of Combined Cinnamon, Clove, and Lemongrass Essential Oils on Enhancing Antioxidant and Antimicrobial Activity

A multivariate mixture system of EOs was employed to evaluate individual, binary, and tertiary effects of cinnamon, clove, and lemongrass essential oils on in vitro antioxidant activity and antimicrobial activity against Botrytis cinerea , Escherichia coli , and Staphylococcus aureus . The highest antioxidant activity was observed with 100% clove oil, showing inhibition rates of 94.97% (DPPH), 93.85% (ABTS). The addition of clove EO to the mixture, in a two-thirds proportion, resulted in inhibition percentages above 80% for both DPPH and ABTS. Regarding the inhibitory effect Botrytis cinerea , lemongrass EO exhibited the best performance, with 68% inhibition, while its combination, even partially, with clove and cinnamon produced a negative effect. Escherichia coli and Staphylococcus aureus , the strongest inhibitory activity was obtained with 100% lemongrass EO (inhibition zones of 7.1 and 6.7 cm). The simultaneous use lemongrass and cinnamon EOs in higher proportions within the mixture resulted in greater inhibition, suggesting a synergistic effect.