Antifungal activity of volatile organic compounds from essential oils against the postharvest pathogens Botrytis cinerea, Monilinia fructicola, Monilinia fructigena, and Monilinia laxa

Abstract

Gray mold and brown rot, caused respectively by Botrytis cinerea and Monilinia spp., are fungal diseases responsible for significant losses during the storage of fruit and vegetables. Nowadays, the control of postharvest diseases is shifting towards more sustainable strategies, including the use of plant secondary metabolites. In this study, the antifungal activity of Origanum vulgare, Thymus vulgaris, Thymus serpyllum, Melaleuca alternifolia, Lavandula officinalis, Lavandula hybrida, Citrus bergamia, Rosmarinus officinalis, Cinnamomum zeylanicum essential oils (EOs) in vapor phase was tested in vitro against B. cinerea, Monilinia fructicola, Monilinia fructigena, and Monilinia laxa. For the experiments, a protocol using a volatile organic compounds (VOC) chamber was designed. Results indicate a dose-dependent inhibitory activity of all the tested EOs, with O. vulgare, T. vulgaris, and T. serpyllum being the most active ones, with minimum inhibitory concentrations (MIC) of 22.73, 45.45, and 22.73 µl/L, respectively, against B. cinerea and a range between 5.64 and 22.73 µl/L against the three Monilinia spp. Overall, B. cinerea presented lower sensitivity to vapor-phase EOs than any of the Monilinia strains, except for the C. zeylanicum EO, which consistently showed higher inhibition against B. cinerea. Among the three Monilinia spp., M. fructicola was the least sensitive, while M. fructigena was the most sensitive. The use of VOC chambers proved to be a reliable protocol for the assessment of antimicrobial activities of EOs. These results suggest that the VOC emitted by the tested EOs are effective towards important decay-causing fungi, and that they could be used for the control of gray mold and brown rot in in vivo trials.

Antifungal Activity of Thirty Essential Oils to Control Pathogenic Fungi of Postharvest Decay

“…Cinnamomum zeylanicum EO in the vapor phase was tested in vitro against B. cinerea, Monilinia fructicola, Monilinia fructigena, and Monilinia laxa. Based on mycelial growth inhibition, the volatiles of C. zeylanicum EO consistently showed higher inhibition against B. cinerea, suggesting a specific mode of action [37]. Vapor phase and direct contact via growth media of EOs could act differently against postharvest fungi [37,38], but this hypothesis needs confirmation.…”

“…Based on mycelial growth inhibition, the volatiles of C. zeylanicum EO consistently showed higher inhibition against B. cinerea, suggesting a specific mode of action [37]. Vapor phase and direct contact via growth media of EOs could act differently against postharvest fungi [37,38], but this hypothesis needs confirmation. On the other hand, A. alternata and, to a lesser extent, P. italicum appear to have a greater ability to tolerate the various antifungal treatments.…”

Carvacrol Encapsulation in Chitosan–Carboxymethylcellulose–Alginate Nanocarriers for Postharvest Tomato Protection

“…A summary of previous studies of carvacrol against B. cinerea, Colletotrichum spp., and Penicillium spp. is presented in Table S1 [43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60]. Caution is advised when interpreting these results due to potential variations in isolates (or species, especially in the genus Colletotrichum and Penicillium) across diverse studies.…”

Efficacy of Essential Oil Vapours in Reducing Postharvest Rots and Effect on the Fruit Mycobiome of Nectarines

“…In vitro and in vivo studies demonstrated the antifungal activity of EOs against fruit postharvest pathogens, such as Botrytis cinerea [29][30][31], Penicillium expansum [32,33], Alternaria spp. [34], and Monilinia spp.…”

“…[34], and Monilinia spp. [31,35]. The antimicrobial activity of EOs has been associated with several mechanisms, including the alteration in cell wall and membrane permeability and changes in gene expression patterns [36].…”