Moringa oleifera seed oil extracted by pressurized n-propane and its effect against Staphylococcus aureus biofilms

ABSTRACT

Staphylococcus aureus is often associated worldwide with foodborne illnesses, and the elimination of biofilms formed by this bacterium from industrial surfaces is very challenging. To date, there have been few attempts to investigate plant oils obtained by recent green technologies, applied against biofilms on usual surfaces of the food industry and bacteria isolated from such environment. Therefore, this study evaluated the activity of Moringa oleifera seed oil (MOSO), extracted with pressurized n-propane, against standard and environmental S. aureus biofilms. Additionally, a genotypic and phenotypic study of the environmental S. aureus was proposed. It was found that this bacterium was a MSSA (methicillin-sensitive S. aureus), a carrier of icaA and icaD genes that has strong adhesion (OD₅₅₀=1.86 ± 0.19) during biofilm formation. The use of pressurized n-propane as a solvent was efficient in obtaining MOSO, achieving a yield of 60.9%. Gas chromatography analyses revealed the presence of a rich source of fatty acids in MOSO, mainly oleic acid (62.47%), behenic acid (10.5%) and palmitic acid (7.32%). On polystyrene surface, MOSO at 0.5% and 1% showed inhibitory and bactericidal activity, respectively, against S. aureus biofilms. MOSO at 1% allowed a maximum reduction of 2.38 log UFC/cm² of S. aureus biofilms formed on PVC (polyvinyl chloride) surface. Scanning electron microscopy showed disturbances on the surface of S. aureus after exposure to MOSO. These unprecedented findings suggest that MOSO extracted with pressurized n-propane is potentially capable of inhibiting biofilms of different S. aureus strains, thus, contributing to microbiological safety during food processing.

GRAPHICAL ABSTRACT

KEYWORDS:

• Plant oil
• antibiofilm
• food industry
• green technology
• biotechnology

Acknowledgements

The authors acknowledge the support of Research Support Center Complex from State University of Maringa, and Coordination for the Improvement of Higher Education Personnel (CAPES) scholarship. The authors acknowledge the BioRender.com for providing the illustrative icons that form the graphical abstract.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethics approval and consent to participate

Not applicable.

Data availability statement

The data that support the findings of this study are available from the corresponding author, A. M. Oliveira, upon reasonable request.

Additional information

Funding

This study was financed in part by the Coordination for the Improvement of Higher Education Personnel, Brazil – Finance Code 001. The Coordination for the Improvement of Higher Education Personnel had no role in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript.