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In order to find effective, biorational, and eco-friendly pest control tools, Cupressus sempervirens var. horizontalis essential oil (EO) was produced using hydrodistillation, before being analyzed with gas chromatography, specifically, using flame ionization detection. The monoterpene components α-pinene (46.3%), δ-3-carene (22.7%), and α-cedrol, a sesquiterpene hydrocarbon, (5.8%), were the main fractions. An oil-in-water nanoemulsion was obtained following a green protocol. The EO, its nanoemulsion, and its terpenes each exhibited both insecticidal and insect repellent activities against the rice weevil, Sitophilus oryzae. In a contact bioassay, the nanoemulsion induced a 100% adult mortality rate in a concentration of 10.0 µL/cm2 after 4 days of treatment, whereas 40 µL/cm2 of EO and α-cedrol was required to kill 100% of weevils. Using fumigation, nanoemulsion and EO at 10 µL/L air caused a 100% adult mortality rate after 4 days of treatment. The LC50 values of botanicals ranged between 5.8 and 53.4 µL/cm2 for contact, and between 4.1 and 19.6 µL/L for fumigation. The phytochemicals strongly repelled the weevil at concentrations between 0.11 and 0.88 µL/cm2, as well as considerably inhibiting AChE bioactivity. They were found to be safe for earthworms (Eisenia fetida) at 200 mg/kg, which also caused no significant alteration in wheat grain viability. This study provides evidence for the potential of using the EO of C. sempervirens and its nanoemulsion as natural, eco-friendly grain protectants against S. oryzae. [ABSTRACT FROM AUTHOR]

BACKGROUND The house mosquito, Culex pipiens L. is a harmful species, widespread in urban areas, and considered the primary enzootic vector of West Nile arbovirus. Widespread insecticide resistance in mosquito populations and the environmental risks and toxicity hazards of chemical pesticides make insecticides an inadequate mosquito control strategy. Seeking ecofriendly tools for mosquito control tools has become necessary. RESULTS: Essential oil (EO) was hydrodistilled from the fruits of Brazilian pepper, Schinus terebinthifolius Raddi and analyzed using gas chromatography–flame ionization detection and gas chromatography–mass spectrometry. An oil‐in‐water nanoemulsion (particle size 41.3 nm) was developed and characterized from EO using a green low‐energy approach. EO, its nanoemulsion and monoterpenes showed mosquitocidal, repellent and acetylcholinesterase inhibitory activities against Cx. pipiens. A nanoemulsion concentration of 30 μl L–1 caused 100% larval mortality after 24 h of exposure, whereas EO, d‐limonene and α‐phellandrene at 60 μl L–1 caused 100%, 92.4% and 88.2% larval mortality, respectively. The concentration that killed 50% of organisms (LC50) for larvae after 24 h ranged between 6.8 and 40.6 μl L–1. Upon fumigation, 15.0 μl L–1 of nanoemulsion killed 94.5% of adults after 24 h of exposure. LC50 values against adults ranged between 5.3 and 31.2 μl L–1. EO products exhibited repellence activity at concentrations between 0.5 and 4.0 μl cm–2. Test materials effectively inhibited the acetylcholinesterase activity of mosquito and were safe toward the non‐target organisms Gambusia affinis and Eisenia fetida. CONCLUSION: There is a potential for using S. terebinthifolius EO, its nanoemulsion and monoterpenes as ecofriendly natural mosquitocides. [ABSTRACT FROM AUTHOR]

[Display omitted] • EO of Achillea biebersteinii was obtained and analyzed using (GC–FID) and (GC–MS). • Oil-in-water nanoemulsion was prepared and characterized from EO. • EO, nanoemulsion and monoterpenes were insecticidal and reduced T. castaneum progeny. • Botanicals significantly inhibited the larval acetylcholinesterase activity. • There is potential for using the test EO products as natural grain protectants. Essential oil (EO) was hydrodistilled from Achillea biebersteinii and analyzed using gas chromatography–flame ionization detection (GC–FID) and (GC–MS). Three monoterpenes, α-terpinene, p -cymene, and camphor were isolated as the main terpenes in the EO. Oil-in-water nanoemulsion (particle size 52.7 ± 4.4 nm) was prepared and characterized from EO through a hydrothermal approach. The EO products caused insecticidal effects and altered F 1 progeny of the red flour beetle, Tribolium castaneum (Herbst) in a dose and exposure time-dependent manner. The nanoemulsion was superior in bioactivity, followed EO. At 12.5 µl/cm2, nanoemulsion and EO caused 100% mortality of the second larvae after 4 days of exposure with reduction of F 1 progeny of 100.0 and 89.2%, respectively. At 50.0 µl/cm2, percentage mortality and reduction in progeny of EO products ranged between (61.4–100%) and (53.0–100%), respectively. Upon fumigation, nanoemulsion at 10 µl/L air caused 100% mortality of the second larvae after 4 days of exposure. At 20 µl/L air and 4 days after treatment, percentage mortality with the remainder botanicals ranging between 64.7 and 100. LC 50 ′s of products after 48 h exposure ranging between 6.7 and 58.1 µg/cm2 in insecticidal bioassay, and between 3.6 and 26.3 µl/L upon fumigation. Botanicals caused a remarkable inhibition of acetylcholinesterase activity (AChE), where nanoemulsion (IC 50 = 14.22 mM), EO (IC 50 = 35.12 mM) and camphor (IC 50 = 23.93 mM) were superior as AChE inhibitors. There is a potential for using of A. biebersteinii EO, its nanoemulsion and monoterpenes as natural grain protectants after the required toxicological investigations. [ABSTRACT FROM AUTHOR]

In the pursuit of searching for novel and environmentally benign insecticides to minimize the environmental risks of synthetic pesticides, essential oil (EO) of Salvia officinalis L., the so-called common sage, was hydrodistilled and analyzed using gas chromatography–flame ionization detection (GC–FID) and Gas chromatography-Mass spectrometry (GC–MS). The monoterpenes, α -thujone (26.8%), camphor (19.9%), and 1,8-cineole (13.4%) were identified as the key fractions. Oil-in-water nanoemulsion (NE) was developed adopting a green low energy method, then characterized for thermodynamic stability. The EO, the NE and monoterpenes showed insecticidal bioactivity against the granary weevil, Sitophilus granarius L. The NE caused the strongest contact bioactivity against larvae (LC 50 =7.2 µL/cm2) after 72 h of exposure. At the same assaying conditions, EO (LC 50 = 14.1 µL/cm2) and camphor (19.3 µL/cm2) exhibited promising bioactivities. For adults, the LC 50's of NE, EO and camphor after 72 h of exposure were 5.8, 9.2, and 19.8 µL/cm2, respectively. Upon fumigation, the NE, EO and camphor were the most effective as fumigants, where LC 50 values after 72 h larval exposure were 8.1, 11.0, and 14.0 µL/L, respectively, and for adult were 5.4, 9.6, and 12.1 µL/L, respectively. The phytochemicals effectively repelled the weevils at low concentrations, and considerably inhibited the activity of acetylcholinesterase (AChE). None-target evaluations proved that the phytochemicals and NE were safe for earthworm, Eisenia fetida (Savigny, 1826) at a limit concentration of 200 mg/kg soil , and the albino rat at an oral limit dose of 4500 mg/kg body weight, except for α -thujone. The test phytochemicals were non-phytotoxic to wheat grains at concentrations reached 150 µL/ml. Results provide evidence for a potentiality for using sage EO, particularly at its nanoscale, as ecofriendly grain protectant against the granary weevil. [Display omitted] • Essential oil of Salvia officinalis was hydrodistilled and analyzed. • Oil-in-water nanoemulsion was prepared and characterized. • The oil products caused insecticidal effects and inhibited AChE of S. granarius. • EO materials were safe toward the non-target earthworm, albino rat and wheat grains. • There is potential for use S. officinalis oil and nanoemulsion as green pesticides. [ABSTRACT FROM AUTHOR]