Center of Excellence in Biotechnological Research Applied to the Environment (CIBAMA-UFRO), Faculty of Engineering and Sciences, Universidad de La Frontera, Av. Francisco Salazar 01145, Casilla 54-D, Temuco, Chile.
Scientific and Technological Bioresource Nucleus (BIOREN-UFRO), Universidad de La Frontera, Av. Francisco Salazar 01145, Casilla 54-D, Temuco, Chile; Laboratory of Geomicrobiology, Department of Chemical Sciences and Natural Resources. Faculty of Engineering and Sciences, Universidad de La Frontera, Av. Francisco Salazar 01145, Casilla 54-D, Temuco, Chile.
Microbiol Res. 2023 Dec;277:127486. doi: 10.1016/j.micres.2023.127486. Epub 2023 Sep 11.
Botrytis cinerea and Penicillium expansum produce deterioration in fruit quality, causing losses to the food industry. Thus, plant essential oils (EOs) have been proposed as a sustainable alternative for minimizing the application of synthetic fungicides due to their broad-spectrum antifungal properties. This study investigated the efficacy of five EOs in suppressing the growth of B. cinerea and P. expansum and their potential antifungal mechanisms. EOs of Mentha × piperita L., Origanum vulgare L., Thymus vulgaris L., Eucalyptus globules Labill., and Lavandula angustifolia Mill., were screened for both fungi. The results showed that the EO of T. vulgaris and O. vulgare were the most efficient in inhibiting the growth of B. cinerea and P. expansum. The concentration increase of all EO tested increased fungi growth inhibition. Exposure of fungi to EOs of T. vulgaris and O. vulgare increased the pH and the release of constituents absorbing 260 nm and soluble proteins, reflecting membrane permeability alterations. Fluorescence microscopic examination revealed that tested EOs produce structural alteration in cell wall component deposition, decreasing the hypha width. Moreover, propidium iodide and Calcein-AM stains evidenced the loss of membrane integrity and reduced cell viability of fungi treated with EOs. Fungi treated with EOs decreased the mitochondria activity and the respiratory process. Therefore, these EOs are effective antifungal agents against B. cinerea and P. expansum, which is attributed to changes in the cell wall structure, the breakdown of the cell membrane, and the alteration of the mitochondrial activity.
灰葡萄孢菌和扩展青霉会导致果实品质下降，给食品工业造成损失。因此，植物精油（EOs）因其广谱抗真菌特性而被提议作为减少合成杀菌剂应用的可持续替代品。本研究调查了五种 EOs 抑制灰葡萄孢菌和扩展青霉生长的效果及其潜在的抗真菌机制。薄荷（Mentha × piperita L.）、牛至（Origanum vulgare L.）、普通麝香草（Thymus vulgaris L.）、蓝桉（Eucalyptus globules Labill.）和狭叶薰衣草（Lavandula angustifolia Mill.）的 EOs 对这两种真菌进行了筛选。结果表明，T. vulgaris 和 O. vulgare 的 EO 对抑制灰葡萄孢菌和扩展青霉的生长最有效。所有测试的 EO 浓度增加都会增加真菌生长抑制。真菌暴露于 T. vulgaris 和 O. vulgare 的 EO 中会增加 pH 值和吸收 260nm 物质和可溶性蛋白质的成分释放，反映出膜通透性的改变。荧光显微镜检查显示，测试的 EOs 会导致细胞壁成分沉积的结构改变，减少菌丝宽度。此外，碘化丙啶和 Calcein-AM 染色证明了用 EOs 处理的真菌的细胞膜完整性丧失和细胞活力降低。用 EOs 处理的真菌降低了线粒体活性和呼吸过程。因此，这些 EOs 是针对灰葡萄孢菌和扩展青霉的有效抗真菌剂，这归因于细胞壁结构的变化、细胞膜的破裂以及线粒体活性的改变。
