Protocol for determining minimum inhibitory concentrations of essential oils against bacterial pathogens using broth microdilution
Essential oils (EOs) are widely investigated for antimicrobial activity, yet minimum inhibitory concentrations (MICs) lack cross-study comparability due to the absence of a harmonized reference assay. Here, we present a protocol to determine MICs of EOs against aerobic bacterial pathogens using a broth microdilution technique. We describe steps for incorporating EO dispersion using Tween 80 and preparing a standardized bacterial inoculum. We detail procedures for establishing two-fold dilution series in 96-well plates and visually determining the MIC endpoint.
Authors
- Melinda Mariotti (ORCID: https://orcid.org/0000-0001-6901-0168)
- Brunella Posteraro (ORCID: https://orcid.org/0000-0002-1663-7546)
- Maura Di Vito (ORCID: https://orcid.org/0000-0002-2991-0855)
- Francesca Bugli (ORCID: https://orcid.org/0000-0001-9038-3233)
- Abdesselam Zhiri (ORCID: https://orcid.org/0000-0002-1234-3460)
- Mattia Di Mercurio
- Domiziana Coggiatti
- Silvia Rizzo
- Maurizio Sanguinetti (ORCID: https://orcid.org/0000-0002-9780-7059)
Institutions
- Università Cattolica del Sacro Cuore (IT)
- Université Libre de Bruxelles (BE)
- Agostino Gemelli University Polyclinic (IT)
Publication Details
- Journal
- STAR Protocols
- Published
- 2026-05-21
- DOI
- https://doi.org/10.1016/j.xpro.2026.104587
- Primary Topic
- Essential Oils and Antimicrobial Activity
- Type
- article
- Field-Weighted Citation Impact
- 0.00