This study investigates the chemical composition of the essential oil obtained from the leaves of Bocageopsis multiflora (Mart.) R.E.Fr (Annonaceae), examining its effectiveness in combating both the larvae and adult forms of Aedes aegypti mosquitoes. Additionally, for a deeper understanding of the insecticidal activity, toxicity properties and molecular docking calculations were conducted using the main compounds of this essential oil. GC/MS analysis revealed the presence of 26 constituents, representing 95.2% of the essential oil, with the major components identified as the sesquiterpenes α-selinene, β-selinene, and β-elemene. Larvicidal assays demonstrated potent activity of this essential oil with significant LC50 values of 40.8 and 39.4 μg/mL at 24 and 48 h, respectively. Adulticidal assessments highlighted strong efficacy with LC50 of 12.5 µg/mL. Molecular docking analysis identified optimal interaction activities of α-selinene and β-selinene with key Aedes proteins. The in silico studies comparing synthetic insecticides with the major sesquiterpenes of the essential oil revealed that β-selinene exhibited a significantly higher binding affinity compared to the other two sesquiterpenes. Also, ADMET studies of the three main sesquiterpenes indicated acceptable drug-like properties. In these findings, safety evaluations showed low toxicity and skin sensitization for the main sesquiterpenes, contrasting with commercial synthetic insecticides. Therefore, in silico analyses suggest promising interactions with Aedes proteins, indicating its potential as an effective alternative to conventional insecticides These results show the larvicidal and adulticidal potential of the essential oil from Bocageopsis multiflora against Aedes aegypti, supported by its predominant constituents, α-selinene, β-selinene and β-elemene.
Human tegumentary leishmaniasis (HTL) is a serious tropical disease caused by Leishmania amazonensis. Developing new leishmanicidal agents can help overcome current treatment challenges, such as drug resistance and toxicity. Essential oils are a source of lipophilic substances with diverse therapeutic properties. This study aimed to determine the anti-L. amazonensis activity, cytotoxicity, and chemical profile of Allium sativum essential oil (ASEO). The effect of ASEO on parasite and mammalian cells viability was evaluated using resazurin and MTT assays, respectively. The oil’s effect against intracellular amastigotes was also determined. Transmission electron microscopy was used to assess the ultrastructural changes induced by ASEO. In addition, the chemical constituents of ASEO were identified by gas chromatography-mass spectrometry (GC-MS). The cytotoxic potential was evaluated in vitro and in silico. The oil displayed IC50 of 1.76, 3.46, and 3.77 µg/mL against promastigotes, axenic, and intracellular amastigotes, respectively. Photomicrographs of treated parasites showed plasma membrane disruption, increased lipid bodies, and autophagic-like structures. ASEO chemical profiling revealed 1,2,4,6-tetrathiepane (24.84%) and diallyl disulfide (16.75%) as major components. Computational pharmacokinetics and toxicological analysis of ASEO’s major components demonstrated good oral bioavailability and better toxicological endpoints than the reference drugs. Altogether, the results suggest that ASEO could be an alternative drug candidate against HTL.
Control of Aedes aegypti, the primary vector of arboviruses such as dengue, Zika, and chikungunya, is increasingly difficult due to resistance to synthetic insecticides and environmental concerns. Plant essential oils offer sustainable alternatives with multi-target modes of action and rapid biodegradation. This study evaluated the insecticidal potential of the essential oil of Aniba canelilla (EOANIB), its major constituent 1-Nitro-2-phenylethane (NFTANE), and the derivative 1-Nitro-2-phenylethene (NFTENE) against larvae and adults of A. aegypti. Acetylcholinesterase (AChE) inhibition was quantified using enzymes from Electrophorus electricus, Aedes aegypti and Drosophila melanogaster. Pluronic® F127 (5% w/v) nanoformulations loaded with EOANIB, NFTANE, or NFTENE at 1.5% or 0.34% (w/v) improved efficacy and stability. Formulations remained stable for 120 to 190 days at 25 to 60 °C. Larvicidal assay at 24 h yielded LC50 values of 86.9 (CI 78.2–94.7) ppm for EOANIB, 84.8 ppm (CI 75.6–92.4) for NFTANE and 10.9 (CI 8.0–14.0) ppm for NFTENE. Against adults, EOANIB achieved an LC50 of 33.9 ppm at 1.5 h. Nanoformulation reduced the EOANIB LC50 by 22.2% after 24 h and 40.1% after 48 h. Toxicity assays evaluated selectivity with Artemia salina (EOANIB LC50: 77.2 ppm) and no mortality in D. melanogaster at 100 ppm. The convergence of efficacy, formulation-enhanced performance, and demonstrated storage stability positions Aniba canelilla as a promising source of bioinsecticide candidates for Aedes aegypti control and supports further development of micellar delivery systems for integrated vector management.
Hemipteran insects such as Euschistus heros and Dysdercus peruvianus are important pests of soybean and cotton, respectively, making them relevant targets in pest management programs. This work aims to evaluate the insecticidal and chemical activity of Cymbopogon citratus essential oil (CC-EO) and its nanoemulsion against E. heros and D. peruvianus. A mixture of citral stereoisomers (59.5%) was identified as the major constituent of CC-EO The topical application of nanoemulsion resulted in 53.33% and 33.33% mortality in E. heros and D. peruvianus, respectively. Contact treatment caused 83.33% mortality in E. heros and 86.70% mortality in D. peruvianus, also inducing antennal deformities observed by scanning electron microscopy and reflected in altered behavioral responses in a Y-tube olfactometer assay. Ovicidal effects were observed in contact treatment for both species, affecting nymph emergence from eggs treated with nanoemulsion. Treatments with pure EO resulted in 100% nymph mortality and complete inhibition of egg hatching in both insects. Headspace solid-phase microextraction (HS-SPME) analysis revealed changes in the volatile profile of treated insects, showing the presence of semiochemicals related to defense and alarm, such as terpenes and alcohols. The multiple lethal and sublethal effects demonstrated by CC-EO highlight its potential as a candidate for integrated pest management programs, offering an eco-friendly alternative to conventional chemical control methods.