In the present investigation, the antifungal activity of essential oil emulsions and nanoemulsions of sweet basil (Ocimum basilicum L.), marjoram (Majorana hortensis Moench), peppermint (Mentha piperita L.), spearmint (Mentha spicata L.) and thyme (Thymus vulgaris L.) were evaluated against Fusarium oxysporum isolated from infested cumin and geranium plants. Essential oils were obtained by hydrodistillation and analyzed by gas chromatography. The nanoemulsion was formulated using the essential oils, non-ionic surfactant (Tween 80) and water by ultrasonication method for 30 min and characterized by particle size analyzer and transmission electron microscope. Essential oil emulsions were prepared as mentioned above without sonication. The transmission electron micrograph showed that the essential oil nanoemulsions were spherical in shape and moderately mono or di-dispersed. The droplet size was correlated well with the results obtained from droplet size analysis showing that droplets are present in the nanometer range, with particle size of less than 100 nm and were stable after 3 months of storage under room temperature (27 °C). Four concentrations of the emulsions and nanoemulsions were used to evaluate the anti-fusarium activity in vitro. The results showed that maximum inhibition against Fusarium oxysporum. f.sp. cumini was resulted by thyme essential oil nanoemulsion and emulsion at 2000 ppm and sweet basil essential oil nanoemulsion at 4000 ppm. Also, maximum inhibition against Fusarium oxysporum isolated from geranium plant resulted by thyme essential oil nanoemulsion and emulsion at 2000 ppm. All essential oil nanoemulsions exhibited higher activities compared to emulsions against fungal growth at all concentrations. Treating cumin seeds with each of the concentrations of essential oil emulsions did not affect germination, while seed germination percentage sharply decreased at high concentrations of nanoemulsions treatments. The results suggest the potential effects of thyme and sweet basil essential oil nanoemulsions as novel fungicide agents against Fusarium spp.

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Fungal plant diseases are considered one of the most destructive diseases for plants. In this current study, Neoscytalidium dimidiatum as a fungal plant pathogen was isolated from an infected Carum carvi L. plant (C. carvi) for the first time and controlled it using clove essential oil nanoemulsion (CEONE). This fungal plant pathogen was identified morphologically and genetically, then deposited in the gene bank under accession number OQ338188. CEONE was prepared and characterized using DLS, Zeta potential, and TEM analysis. The characterization results illustrated that the size of CEONE was lower than 100 nm, which was confirmed by TEM, which appeared spherical in shape. Results revealed that CEONE has promising antifungal activity towards N. dimidiatum, where inhibition percentages of CEONE at concentrations of 5000, 3000, and 1000 ppm were 82.2%, 53.3%, and 25.5%, respectively. At the pot level, N. dimidiatum was highly virulent on C. carvi, and CEONE and CEO were highly effective against N. dimidiatum blight disease, with 71.42% and 57.14% protection, respectively. Moreover, results revealed that there was a vast improvement in root length, plant height, and leaves. Additionally, the application of CEONE and CEO induced plant resistance by modifying proline, phenol, hydrogen peroxide, malondialdehyde, and antioxidant enzymes. In conclusion, N. dimidiatum was highly virulent on C. carvi but can be effectively reduced by CEONE through the eco-friendly method.

In the current study, clove oil nanoemulsion (CL-nanoemulsion) and emulsion (CL-emulsion) were prepared through an ecofriendly method. The prepared CL-nanoemulsion and CL-emulsion were characterized using dynamic light scattering (DLS) and a transmission electron microscope (TEM), where results illustrated that CL-nanoemulsion droplets were approximately 32.67 nm in size and spherical in shape, while CL-nanoemulsion droplets were approximately 225.8 nm with a spherical shape. The antibacterial activity of CL-nanoemulsion and CL-emulsion was carried out using a microbroth dilution method. Results revealed that the preferred CL-nanoemulsion had minimal MIC values between 0.31 and 5 mg/mL. The antibiofilm efficacy of CL-nanoemulsion against S. aureus significantly decreased the development of biofilm compared with CL-emulsion. Furthermore, results illustrated that CL-nanoemulsion showed antifungal activity significantly higher than CL-emulsion. Moreover, the prepared CL-nanoemulsion exhibited outstanding antifungal efficiency toward Candida albicans, Cryptococcus neoformans, Aspergillus brasiliensis, A. flavus, and A. fumigatus where MICs were 12.5, 3.12, 0.78, 1.56, and 1.56 mg/mL, respectively. Additionally, the prepared CL-nanoemulsion was analyzed for its antineoplastic effects through a modified MTT assay for evaluating apoptotic and cytotoxic effects using HepG2 and MCF-7 cell lines. MCF-7 breast cancer cells showed the lowest IC50 values (3.4-fold) in CL-nanoemulsion relative to that of CL-emulsion. Thus, CL-nanoemulsion induces apoptosis in breast cancer cells by inducing caspase-8 and -9 activity and suppressing VEGFR-2. In conclusion, the prepared CL-nanoemulsion had antibacterial, antifungal, and antibiofilm as well as anticancer properties, which can be used in different biomedical applications after extensive studies in vivo.

Chia (Salvia hispanica L.) is one of the most important medicinal plants recently introduced to Egyptian cultivation and has significant multiusing in human curing. Fusarium oxysporum, F. roseum, F. semitectum, F. solani, Macrophomina phaseolina, Pythium ultimum, Rhizoctonia solani and Sclerotinia sclerotiorum were isolated from infected plants, showing root and stem rot symptoms collected from different localities of Giza and Fayoum governorates. The isolated fungi significantly realized different (%) of damping-off and root and stem rot. Rhizoctonia solani, M. phaseolina and F. oxysporum were the most aggressive fungi in the pathogenicity test. Bacillus spp. and Trichoderma spp. gave different degrees of antagonistic effects against the tested pathogens, i.e., F. oxysporum, M. phaseolina and R. solani in vitro. Ascorbic and citric acids at 500 ppm recorded 100% seed germination in vitro. Under greenhouse conditions, Bio-Zeid, T. harzianum, B. subtilis and ascorbic acid gave the highest decreasing percentages of pre, post-emergence damping-off, root and stem rot and maximized healthy survivals. Under field conditions, Bio-Zeid, T. harzianum and ascorbic acid gave the highest decrease percentages of damping-off and root and stem rot and maximized plant survivals in the two experimental seasons, as well as increased plant growth parameters compared with the control (without treatment). Thus, it could be suggested that any of Bio-Zeid as formulated compound, also, ascorbic acid and T. harzianum can be formulated to be used for controlling chia damping-off and root and stem rot.