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Background: The scale insect, Parlatoria ziziphi (Lucas) (Diaspididae: Hemiptera), is one of the most serious insects in citrus orchards in Egypt. The efficiency of two different formulation types (emulsifiable concentrates (EC) and nanoemulsions) based on the essential oils Artemisia herba-alba (Asso.) (Asterales: Asteraceae) and Laurus nobilis (L.) (Laurales: Lauraceae) at two concentrations of 3 and 5%, compared with the commercial mineral oil, Active Cable, was examined against P. ziziphi. The green formulations were named Artemisia and Laury relative to A. herba-alba and L. nobilis, respectively. The physicochemical properties of the tested formulations have been studied. Results: All the EC formulations of the essential oils (EOs) as well as the nanoemulsions with ratios of EOs to Tween 1:1.5 (Artemisia) and 1:2 (Laury) passed all the tested characteristics. The droplet sizes of the successful nanoemulsions' formulations by the ultrasonic emulsification were 153.7, 113.4 nm for Artemisia and 139.3, 89.4 nm for Laury at 3 and 5% concentrations, respectively. Laury EC caused average reductions of 92.79 and 94.94% (nymphs and females) when applied at 3 and 5%, respectively, while the same oil prepared as nanoemulsions caused average reductions of 50.02 and 55.32% at the same concentrations, compared with 91.74% reduction resulted from spraying Active Cable. Moreover, Artemisia caused reduction percentages of 74.97, 91.52 for EC and 43.7, 54.01 for nanoemulsions, sprayed at 3 and 5%, respectively. Although EC emulsions were more effective in reducing insect populations than nanoemulsion formulations, the efficiency of nanoemulsions gradually increased with time elapsed. The antioxidant activities of superoxide dismutase, catalase, and polyphenol oxidase enzymes were researched. It is recognized that insect infestations increase plant enzyme activity to defend them against insect attack. The results revealed a significant reduction of all the examined enzymes which were more obvious for EC emulsions than nanoemulsions. Conclusions: The EC formulations originated from the EOs, especially Laury 3% EC and Artemisia 5% EC, could be an alternative to the traditional insecticides for controlling the scale insect, P. ziziphi. [ABSTRACT FROM AUTHOR]

A study conducted in Egypt during 2017 to describe preparation of oil-in-water (O/W) nanoemulsions for different insecticides through ultrasonic emulsification technique. The stability of nanoemulsions over a time period, polydispersity index, droplet size, viscosity, and pH were investigated. The results of dynamic light scattering measurements showed that prepared nanoemulsions had a droplet size distribution of lower than 200 nm. The particle size of chlorpyrifos, malathion, cypermethrin, deltamethrin and lambda-cyhalothrin was 18.35, 177.2, 84.99, 24.42 and 79.05 nm, respectively with PDI values from 0.121 to 0.377. The transmission electron microscopy confirmed that these nanoparticles have spherical shape. The viscosity of all formulations ranged from 2.00 to 27.23 mPa.s and pH was around 6.0. The prepared nanoemulsions remained stable over four months of storage at room temperature. This result proved that all selected insecticides were successful in their preparation with a nanometric size range indicating to the possibility of developing suitable formulations as alternatives to traditional emulsifiable concentrate formulations. [ABSTRACT FROM AUTHOR]

Jojoba (Simmondsia chinensis (Link) C.K. Schneid) is a dioecious plant in desert and semi-desert areas, e.g., the Ismailia Desert in Egypt. Jojoba oil (JJBO) is a natural slight yellow oil with the functions of skin barrier repairing and wound healing, which is dermally applied as a traditional medication or cosmetic in the Middle East. The objective of this study was to prepare JJBO dry nanoemulsion powders (JNDs) and investigate their anti-acute lung injury effects. JJBO nanoemulsions (JNEs) were prepared and then lyophilized to JNDs and the properties and simulated lung deposition were measured. Rat acute lung injury (ALI) models were established after intratracheal (i.t.) administration of lipopolysaccharide (LPS) or hydrogen peroxide (H2O2). JNDs and dexamethasone (DXM) solutions were also i.t. administered to the rats. The pathological states of lung tissues were checked. Inflammatory and oxidative factors in the lung tissues were determined using ELISA methods. NF-κB p65 and caspase-3 were measured with a Western blotting method and an immunohistochemical method, respectively. JNDs had an appropriate mass median aerodynamic diameter (MMAD) of 4.17 µm and a fine particle fraction (FPF) of 39.11%. JNDs showed higher anti-inflammatory effect on LPS-induced ALI than DXM with a decrease in total protein content and down-regulation of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and NF-κB p65. JNDs also showed higher anti-inflammatory and anti-oxidation effect on H2O2-induced ALI than DXM with elimination of reactive oxygen species (ROS), increasing of superoxide dismutase (SOD), decrease in of lipid peroxide malondialdehyde (MDA) and glutathione (GSH), and inhibition of caspase-3 expression. Moreover, i.t. JNDs attenuated bleeding and infiltrations of the inflammatory cells in the two ALI models. JNDs are a promising natural oil-contained inhalable medication for the treatment of LPS- or H2O2-induced ALI. [ABSTRACT FROM AUTHOR]

• Nanoemulsions of some natural oils i.e., clove, black seed, orange and lemon and their fungicidal activity against postharvest fruit rot of cucumber were prepared and studied. • Nanoformulations of clove and black seed essential oils (2:1) reduced mycelial linear growth, andcompletely inhibited (100%) conidia sporulation of fungal isolates. • Nanoformulation of clove and black seed essential oils (2:1) respectively is a promising safe alternative fungicide for application against postharvest rot of cucumber fruits management. There are growing concerns about the extensive use of synthetic fungicides worldwide due to their negative health effect on humans, ecosystem, and the development of fungal resistance. Therefore, developing new and safe eco-friendly antifungal agents such as plant-based oils is of major interest. This study was conducted for the first time to develop and evaluate the efficiency of eco-friendly nanoemulsions of some natural oils and evaluating of its efficiency against postharvest fruit rot of cucumber caused by the following fungal isolates: Galactomyces candidum (MF373433), Alternaria tenuissima (MF 373440) and Fusarium solani (MF373443). Nanoemulsions of clove, black seed, lemon, and orange oils were formulated by using ultrasound and subjected to physicochemical and stability studies. The efficiency of these nanoemulsions was evaluated against the postharvest fruit rot fungi of cucumber. The oils of promising nanoemulsions have been analyzed by gas chromatography-mass spectrometry analysis (GC/MS). The acute toxicity study was conducted on rats and on the luminescence emitted of Vibrio fischeri bacteriausing Microtox®. The smaller droplet size of nanoemulsions was found after 10 min of sonication with an oil to Tween 80 ratio of 1:1 and 1:2 for clove and black seed oils, respectively. Nanoemulsion of black seed and clove oils from Egypt at 5000 ppm showed a significantly high reduction in the linear mycelial growth of fungal isolates. The mixture formula (2:1 v/v) of nanoemulsions of clove and black seed oils showed a significantly high reduction in linear mycelial growth, completely inhibited (100%) conidia sporulation of fungal isolates, and highly reduced the percentage of the rot of germinated seeds as well mortality of cucumber developed seedlings. Nanoemulsion formulation of clove and black seed (2:1) at concentration 2.0 % as soaking treatment of cucumber fruits before artificial infestation by inocula of fungal pathogens caused completely (100%) suppress postharvest fruit rot of cucumber. Both clove and black seed oils nanoemulsions and their combination showed no signs of toxicity or mortality in rats and no toxic effects on the luminescence emitted of Vibrio fischeri bacteria using Microtox® assay. Therefore, it can be concluded that the nanoformulation of clove and black seed oils at the ratio of 2:1 is a promising green and safe alternative to synthetic fungicide for application against postharvest rot of cucumber fruits. [ABSTRACT FROM AUTHOR]