Modeling the Growth and Death of <i>Staphylococcus aureus</i> against <i>Melaleuca armillaris</i> Essential Oil at Different pH Conditions

Essential oils (EO) are a great antimicrobial resource against bacterial resistance in public health. Math models are useful in describing the growth, survival, and inactivation of microorganisms against antimicrobials. We evaluated the antimicrobial activity of <i>Melaleuca armillaris</i&g...

Full description

Bibliographic Details
Main Authors: Daniel Buldain, Lihuel Gortari Castillo, María Laura Marchetti, Karen Julca Lozano, Arnaldo Bandoni, Nora Mestorino
Format: Article
Language:English
Published: MDPI AG 2021-02-01
Series:Antibiotics
Subjects:
Online Access:https://www.mdpi.com/2079-6382/10/2/222
Description
Summary:Essential oils (EO) are a great antimicrobial resource against bacterial resistance in public health. Math models are useful in describing the growth, survival, and inactivation of microorganisms against antimicrobials. We evaluated the antimicrobial activity of <i>Melaleuca armillaris</i> EO obtained from plants placed in the province of Buenos Aires (Argentina) against <i>Staphylococcus aureus.</i> The minimum inhibitory and bactericidal concentrations were close and decreased, slightly acidifying the medium from pH 7.4 to 6.5 and 5.0. This result was also evidenced by applying a sigmoid model, where the time and EO concentration necessaries to achieve 50% of the maximum effect decreased when the medium was acidified. Moreover, at pH 7.4, applying the Gompertz model, we found that subinhibitory concentrations of EO decreased the growth rate and the maximum population density and increased the latency period concerning the control. Additionally, we established physicochemical parameters for quality control and standardization of <i>M. armillaris</i> EO. Mathematical modeling allowed us to estimate key parameters in the behavior of <i>S. aureus</i> and <i>Melaleuca armillaris</i> EO at different pH. This is interesting in situations where the pH changes are relevant, such as the control of intracellular infections in public health or the development of preservatives for the food industry.
ISSN:2079-6382