TITLE:
In Vitro and in Situ Antifungal Potential of Essential Oils and Nanoemulsions from Two Cameroonian Aromatic Plants against Pathogens Responsible for Post-Harvest Fruit Rot of Solanum lycopersicum L. (Solanaceae)
AUTHORS:
Adalbert Sonfack, Pamela Francine Kamsu Noumegna, Bertin Sone Enone, Jeannette Fabiola Dikongue Ndondoni, Guy Patrick Evina Abessolo, Pierre Michel Jazet Dongmo
KEYWORDS:
Antifungal Potential, In Vitro and in Situ, Essential Oils, Solanum lycopersicum L., Foeniculum vulgare, Thymus vulgaris
JOURNAL NAME:
Open Journal of Medical Microbiology,
Vol.15 No.4,
December
25,
2025
ABSTRACT: Introduction: Post-harvest tomato storage faces several phytosanitary challenges, particularly damage caused by pathogenic microorganisms. The objective of this study is to evaluate the in vitro and in situ antifungal potential of essential oils and nanoemulsions from two Cameroonian aromatic plants against pathogens responsible for post-harvest tomato fruit rot, with the aim of extending the shelf life of this food product. Methodology: This study was conducted on healthy and infected tomato (Solanum lycopersicum L.) fruits of the (Rio) variety, grown in Dschang, in the West Region of Cameroon. Samples were brought to the laboratory between July and October 2024. The two Cameroonian aromatic plants used for essential oil extraction were fresh thyme (Thymus vulgaris) leaves and fennel (Foeniculum vulgare) seeds. Extraction was performed using a Clevenger hydro-distiller. Nanoemulsions were obtained using an emulsification method with some modifications. Extraction yields were calculated and the oils were characterized by gas chromatography-mass spectroscopy (GC/MS). The medium used for fungal culture was pre-prepared potato dextrose agar. Antifungal activities were evaluated in vitro for the Foeniculum vulgare oil and in situ for the essential oil and the Thymus vulgaris nanoemulsion on the mycelial growth of the isolates. These evaluations were performed using the solid-state dilution method, and subsequently, the antimicrobial activity parameters and rot diameters were determined. The data were subsequently analyzed using IBM SPSS Statistics Version 20.0. Duncan’s multiple ranges test was used for pairwise comparisons if the ANOVA result was significant. Results: This study shows that all essential oils (EOs) have a liquid consistency and a density lower than that of water. EO yields varied from one plant species to another. Chemical analysis by GC/MS revealed 29 and 23 compounds, respectively, identified in the EOs of Fragmentus vulgare and Thymus vulgaris, with anethole (57.20%) and thymol (40.8%) being the major products. Essential oils and their nanoemulsions exhibited varying degrees of antifungal activity against the mycelial growth of Rhizopus stolonifer (MB4) and Colletotrichum cococodes (MB5) isolates. These effects were dose-dependent and pathogen-specific. Conclusion: These essential oils are rich in bioactive compounds and possess innovative properties. They can serve as a basis for post-harvest tomato preservation against microorganisms responsible for rot.