Cattle tick (Rhipicephalus microplus) is a major vector of hemoparasitic diseases and causes significant economic losses in livestock. Control efforts face challenges, including the scarcity of environmentally and human health-friendly methods. This study evaluated the acaricidal activity of ethanolic extracts from Melinis minutiflora harvested at 60, 90, and 120 days. Extract composition was characterized by gas chromatography-mass spectrometry (GC-MS); extractable biomass per hectare was estimated, and potential mechanisms of action were explored via molecular docking. Leaves, stems, and, for 90- and 120-day plants, inflorescences, were extracted using Soxhlet, and acaricidal efficacy was assessed through adult immersion and larval packet tests; reproductive parameters were used to calculate extract effectiveness (PE). Docking targeted eight tick proteins, including GABA receptor, acetylcholinesterase (AChE), triosephosphate isomerase (TIM), glutathione S-transferase (GST), and four mitochondrial electron transport complex subunits. Multivariate analysis summarized metabolite-target interactions. Adult mortality ranged from 37% to 70%, the highest for the 120-day extract, whereas larval mortality approached 100% across all treatments. Reproductive indices were significantly inhibited, yielding PE values between 51% and 91%, the latter for the 120-day extract. GC-MS revealed predominant tocopherol derivatives, pentacyclic triterpenes, and sterols. Docking indicated that metabolites enriched in the 120-day extract, α-tocospiro A, γ-tocopherol, α-tocopherol, and 2-stearoylglycerol, exhibited strong predicted interactions, mainly with mitochondrial complexes, while compounds unique to the 90-day extract showed higher affinity for GABA. Estimated extract production suggests significant biomass bioprospecting potential. These findings highlight the acaricidal potential of M. minutiflora, especially at 120 days, and identify candidate metabolites for sustainable tick control in low-input systems.

Abstract The blood-sucking ectoparasite Rhipicephalus B. microplus represents one of the greatest economic threats to livestock worldwide. The discovery of novel acaricidal molecules based on environmentally sustainable technologies is therefore required, particularly those suitable for use in dairy and meat-producing livestock without generating contaminant residues. This study aimed to identify and validate plant-derived metabolites with dual activity on acetylcholinesterase and mitochondrial targets as sustainable acaricidal agents against R. microplus , integrating computational screening, biochemical assays and field evaluation. Following in silico screening of 1.300 plant metabolites targeting acetylcholinesterase and mitochondrial function, fourteen compounds were selected for in vitro and in vivo mortality assays using immersion and larval vessel methods. Carvacrol was identified as the most promising metabolite and showed an inhibitory mechanism of action on acetylcholinesterase and mitochondrial complexes I, III, and IV. Its acaricidal efficacy was subsequently confirmed under field conditions using ethanolic and oily formulations (spray and pour-on) applied to cattle ( Bos taurus ). The spray formulation significantly reduced tick infestation, decreasing tick counts by 20% every 10 days (p < 0.001), whereas the pour-on formulation showed no significant reduction (p = 0.093). These results demonstrate that an integrated discovery pipeline from computational screening to field validation provides a robust strategy for identifying plant-derived acaricidal agents targeting key physiological pathways in R. microplus . Highlights Structured and sequential workflow (pipeline) from in silico to Bos taurus Identification and validation of phytometabolites against R. microplus Carvacrol multitarget activity on acetylcholinesterase and bioenergetic in ticks The spray formulation reduces tick infestation by 20% every 10 days Graphical abstract Created in BioRender. Avendaño, G. (2026) https://BioRender.com/7pm1ffj

Reducing Aedes aegypti population using natural or synthetic insecticides remains one of the main strategies for controlling diseases such as dengue, Zika or Chikungunya, as this mosquito is their primary vector. Traditionally, some organic compounds -mainly carbamates or organophosphates derivatives- have been employed for this purpose. These insecticides act as irreversible inhibitors of the acetylcholinesterase enzyme (AChE), which results in high nonspecific toxicity. Moreover, the eventual development of resistance highlights the need to explore new alternatives. In this study a series of sixteen (16) new N-arylmethyl-1,2,3,4-tetrahydroquinoline derivatives containing an N-arylmethylpiperidine scaffold inspired by the structure of donepezil structure, were designed and synthesized, using a mild and efficient methodology via cationic Povarov reaction. This approach enabled access to the N-arylmethyl tetrahydroquinoline core with good to high yields (61-94 %). The biological activity of these compounds was then evaluated through insecticidal activity and acetylcholinesterase inhibition assays, as indicators of their potential as insecticidal agents. In preliminary insecticidal activity assay, compounds 4d, 4e, 4f and 4j were identified as the most active, with LC50 of 42, 21, 88 and 65 μg/mL after 24 h of treatment. Enzymatic assays showed that compounds 4a, 4e and 4 m exhibited the highest inhibitory activity, with IC50 values of 8.32 ± 0.32, 16.43 ± 1.13, and 13.23 ± 1.42 μM, respectively. Among them, compound 4e emerged as the most promising candidate. Finally, silico studies, including molecular dynamics simulations and binding free energy calculations, revealed the stability and strong binding interactions of the three most active compounds (4a, 4e, and 4 m) against A. aegypti AChE.

The present study aims to disclose the design of an electronic nose capable of learning and differentiating semiochemical signals from insects usable to identify species that transmit Chagas disease. The proposed device used different non-specific resistor gas sensors integrated into a system of artificial intelligence models. To validate the nose, we used eight insect species of the Triatominae subfamily and one population that was a natural carrier of the parasite Trypanosoma cruzi. Also, the discriminatory capacity of distant species was tested with other insects like Aedes aegypti (arbovirus vector) and Sitophilus oryzae (stored grains plague). As a result, the electronic nose was able to differentiate up to gender level with an accuracy of 89.64% and to differentiate Rhodnius pallensces naturally infected with T. cruzi with less than 1% error in classification. These results show that our designed device can detect particular smelling footprints, and one electronic nose like that could be a tool to discriminate against insects in the future.

Cellular respiration parameters provide information on the energy metabolism of an organism under physiological or non-conditions and can be determined by isolating mitochondria or even using their permeabilized tissue. The present study aimed to describe the mitochondrial activity of Ae. aegypti throughout its life cycle. For this purpose, we isolated mitochondria and permeabilized tissue (1 and 5 individuals) from larvae (L4), pupae, and adults (female thorax) to estimate oxygen consumption using different oxidizable substrates (glutamate, malate, proline + pyruvate, succinate, and glycerol-3-phosphate). The Respiratory Control Coefficient (RCC) was calculated, and the specific enzyme activity of the Electron Transport Chain (ETC) was quantified. The highest values of oxygen consumption (state 3) were obtained when succinate was used as the oxidizable substrate in all developmental stages of Ae. aegypti , with a progressive increase in the values recorded from larva (isolated mitochondria: 30.3 ± 5.0 pmol/(s*mL), permeabilized tissue/ 5 individuals: 48.8±1.8 pmol/(s*mL)), through pupa (isolated mitochondria: 42.8±3.6 pmol/(s*mL); permeabilized tissue/5 individuals: 47.4±2.2 pmol/(s*mL)), through adult (isolated mitochondria: 53.4±6.0 pmol/(s*mL); permeabilized tissue/5 thorax: 27.4±2.4 pmol/(s*mL)). These results are congruent with the values obtained for enzyme activity, with higher activity of succinate oxidase and succinate dehydrogenase enzymes (Complex II). The CCR values for isolated mitochondria and permeabilized tissue ranged from 1 to 1.8. The results allow us to conclude that there are changes in mitochondrial respiration throughout the life cycle of the Ae. aegypti mosquito. ### Competing Interest Statement The authors have declared no competing interest.

Chagas disease, also known as American Trypanosomiasis, is a zoonosis with global distribution caused by the parasite Trypanosoma cruzi, primarily transmitted through the feces of infected triatomines. The emergence of new cases highlights the importance of early pathogen detection in vectors and reservoirs to generate effective control strategies and establish preventive policies. The objective of this study was to design and validate a detection system of T. cruzi based on specific DNA cleavage, activation of Cas12a and trans-cleavage, targeting the genes Cytochrome B (Cytb), 18 S ribosomal subunit (SR18 s), and histone (H2 A). This system was validated for their uses in both vectors and reservoirs of the parasite. The initial step involved performing a bioinformatic analysis of the target genes, followed by the design of RNA guides specific to each cleavage site, along with primers for amplifying the target region through PCR and RPA. Subsequently, we sequenced the amplified DNA target and validated the detection system using T. cruzi DNA extracted from naturally infected Rhodnius pallescens in the metropolitan area of Bucaramanga, Colombia. After standardizing the method, we tested the CRISPR/Cas system with Silvio X10 laboratory strain of T. cruzi and scaled up to blood samples of naturally infected Didelphis marsupialis. As a result, we observed DNA cleavage using the CRISPR/Cas system with the Cytb guide, achieving a detection sensitivity of 118 parasite equivalents/mL in PCR and 116 parasite equivalents/mL with RPA amplification. Sequencing of the Cytb gene showed no mutations in the cleavage site. However, point mutations and indels were found in SR18S and H2 A, avoiding the formation of the CRISPR/LbCas12 complex. Furthermore, we introduce the design of a fluorescent detection prototype with CRISPR/LbCas12a called "Tropical Diseases Detector" (TropD-Detector). This device operates with an excitation wavelength of 480 nm emitted by an LED and a high-pass light filter with a cutoff wavelength of 500 nm. We detected positive samples using any photographic camera system. The TropD-Detector provides a visual, viable, and sensitive method for detecting T. cruzi in both vectors and reservoirs from endemic areas.

Developing new pesticides poses a significant challenge in designing next-generation natural insecticides that selectively target specific pharmacological sites while ensuring environmental friendliness. In this study, we aimed to address this challenge by formulating novel natural pesticides derived from secondary plant metabolites, which exhibited potent insecticide activity. Additionally, we tested their effect on mitochondrial enzyme activity and the proteomic profile of Ae. aegypti, a mosquito species responsible for transmitting diseases. Initially, 110 key compounds from essential oils were selected that have been reported with insecticidal properties; then, to ensure safety for mammals were performed in silico analyses for toxicity properties, identifying non-toxic candidates for further investigation. Subsequently, in vivo tests were conducted using these non-toxic compounds, focusing on the mosquito's larval stage. Based on the lethal concentration (LC), the most promising compounds as insecticidal were identified as S-limonene (LC50 = 6.4 ppm, LC95 = 17.2 ppm), R-limonene (LC50 = 9.86 ppm, LC95 = 27.7 ppm), citronellal (LC50 = 40.5 ppm, LC95 = 68.6 ppm), R-carvone (LC50 = 61.4 ppm, LC95 = 121 ppm), and S-carvone (LC50 = 62.5 ppm, LC95 = 114 ppm). Furthermore, we formulated a mixture of R-limonene, S-carvone, and citronellal with equal proportions of each compound based on their LC50. This mixture specifically targeted mitochondrial proteins and demonstrated a higher effect that showed by each compound separately, enhancing the insecticidal activity of each compound. Besides, the proteomic profile revealed the alteration in proteins involved in proliferation processes and detoxification mechanisms in Ae. aegypti. In summary, our study presents a formulation strategy for developing next-generation natural insecticides using secondary plant metabolites with the potential for reducing the adverse effects on humans and the development of chemical resistance in insects. Our findings also highlight the proteomic alteration induced by the formulated insecticide, showing insight into the mechanisms of action and potential targets for further exploration in vector control strategies.

Characterizing the sand fly diversity is crucial for an effective design of control strategies for Leishmaniasis. We aimed to characterize the sand fly biodiversity around the Tona Reservoir (Santander, Colombia) and to compare the performance of four sampling methods. A sampling of insects was performed in 2017 in the most preserved and least preserved areas close to the Tona Reservoir, using Torre Vigia-UIS and HomeTrap-UIS, two sticky traps previously designed by our working group, CDC, and Bg-Sentinel traps. We collected 268 Phlebotominae specimens, most with CDC (47.8%) and Torre Vigia-UIS (30.2%) traps. Some specimens (47%) could not be determined because of their preservation status; these samples came mostly from the sticky traps. We found 16 sand fly morphospecies, of which 12 were determined to species level. Here, we report two new records for Santander: Pintomyia youngi ([Feliciangeli and Murillo, 1987][1]) and Lutzomyia ceferinoi (Ortíz and Álvarez, 1963). We also collected some confirmed vectors of Leishmania : Pi. youngi , Lutzomyia gomezi (Nitzulescu, 1931), and Lu. longipalpis (Lutz and Neiva, 1912). The highest diversity was collected in the most disturbed area (15 spp.), and in the rainy season (April, 12 spp.). Pintomyia youngi distribution was broad through the Tona Reservoir in all the sampled periods, and we suggest tracking it to infer leishmaniasis risk in the Tona Reservoir. Torre Vigia-UIS seems a valuable tool for vector control, but we do not recommend it for biodiversity studies.### Competing Interest StatementThe authors have declared no competing interest. [1]: #ref-10

Ticks and tick-borne diseases have gained increasing attention in recent years due to their impact on public health and significant losses in livestock production. The use of synthetic compounds for tick control is becoming problematic, mainly due to the resistance to commercially available products as well as their toxicity. Therefore, new alternative control methods are required. For this purpose, plant-derived extracts may be considered as effective repellents and/or acaricides. The present literature review focuses on studies evaluating the acaricidal and repellent activity of plant-derived extracts and plant secondary metabolites. We also noted recent advances in protein-ligand-docking simulation to examine the possible toxic effect of natural chemical compounds on ticks. In conclusion, plant-derived repellents/acaricides can be effective against ticks, especially in rural areas and livestock farms.

Searching for new bioactive molecules to design insecticides is a complex process since pesticides should be highly selective, active against the vector, and bio-safe for humans. Aiming to find natural compounds for mosquito control, we evaluated the insecticidal activity of essential oils (EOs) from 20 American native plants against Aedes aegypti larvae using bioassay, biochemical, and in silico analyses. The highest larvicide activity was exhibited by EOs from Steiractinia aspera (LC 50 = 42.4 µg/mL), Turnera diffusa (LC 50 = 70.9 µg/mL), Piper aduncum (LC 50 = 55.8 µg/mL), Lippia origanoides (chemotype thymol/carvacrol) (LC 50 = 61.9 µg/mL), L. origanoides (chemotype carvacrol/thymol) (LC 50 = 59.8 µg/mL), Hyptis dilatata (LC 50 = 61.1 µg/mL), Elaphandra quinquenervis (LC 50 = 61.1 µg/mL), and Calycolpus moritzianus (LC 50 = 73.29 µg/mL) after 24 h. This biological activity may be related to the disruption of the electron transport chain through the mitochondrial protein complexes. We hypothesized that the observed EOs' effect is due to their major components, where computational approaches such as homology modeling and molecular docking may suggest the possible binding pose of secondary metabolites that inhibit the mitochondrial enzymes and acetylcholinesterase activity (AChE). Our results provided insights into the possible mechanism of action of EOs and their major compounds for new insecticide designs targeting the mitochondria and AChE activity in A. aegypti for effective and safe insecticide.

Visceral leishmaniasis (VL) is a disease caused by species of the Leishmania donovani complex that is mainly transmitted through the urban cycle involving dogs as the primary reservoir. In Colombia, the incidence of VL is increasing, along with the spread of potential vectors. This study aims to investigate the eco-epidemiological factors associated with Leishmania spp. infection in dogs from the Metropolitan Area of Bucaramanga (MAB), Santander, eastern Colombia, which is a region at risk for VL. We conducted molecular and serological sur-veillance of Leishmania spp. in 207 dogs from MAB to determine the epidemiological factors associated with infection. Subsequently, we carried out a molecular and serological analysis of phlebotomine and humans, respectively, in areas with a higher prevalence of infection, aiming to describe the main features associated with the transmission cycle. Out of the 207 dogs tested, 37 (17.8%, 95% CI = 12.6-23.1%) were positive for the presence of Leishmania antibodies by the IFAT test, and only 9 (4.3%, 95% CI = 1.55-7.15%) were positive for L. infantum by PCR. Multivariate analyses indicated that canine shelters and dogs with clinical signs commonly associated with canine VL had a higher prevalence of infection (P < 0.05). In the entomological survey, 69 blood -fed female phlebotomine of the genus Lutzomyia were captured in canine shelters, among them, 55% were identified as Lutzomyia camposi, 29% as Lu. ovallesi, 7% as Lu. dubitans, 6% as Lu. torvida, and 3% as Lu. cayennensis. The identified meal sources of the phlebotomine included human, pig, avian, cattle, and porcupine (Coendou quichua) blood. However, no phlebotomine positive for Leishmania spp. were detected by molecular analyses. Finally, 14 humans who had frequent contact with L. infantum-positive dogs were analyzed through rK39 test, but none tested was positive for IgG/IgM antibodies. The molecular and serological analyses indicate the circulation of L. infantum in dogs from MAB, with canine shelters having the highest prevalence of infection. The entomological survey of canine shelters showed a significant diversity of phlebotomine without potential vectors of L. infantum, suggesting the presence of infection in dogs from these areas could take place in other locations or through other transmission routes. The circulation of L. infantum in multiple dogs from MAB suggests a latent risk of zoonotic transmission of VL in these cities.

Natural-based compounds with repellent activity arise nowadays with the possibility to replace commercial synthetic repellents wholly or partially, such as N,N -Diethyl-m-toluamide (DEET). It is due to DEET's demonstrated toxicity and cutaneous irritation for human beings. Besides, research recommends avoiding using it with kids and pregnant women. The search for a repellent product implies early stages of detailed research that resolve the modes of action against the target insect. Therefore the objective of the current study was to analyze neuronal electrophysiological signals and olfactory system protein expression when the Aedes aegypti mosquito with exposition to natural-based repellents. Adult females of Ae. aegypti of Rockefeller strain were exposed to specific concentrations of repellent compounds like geranyl acetate, α-bisabolol, nerolidol, and DEET. The neuronal effect was measured by electroantennography technique, and the effect of exposure to either DEET or a mixture of natural molecules on protein expression was determined with 2D-PAGE followed by MALDI-TOF-mass spectrometry (MS). This approach revealed that DEET affected proteins related to synapses and ATP production, whereas natural-based repellents increased transport, signaling, and detoxification proteins. The proteomic and electrophysiology experiments demonstrated that repellent exposure disrupts ionic channel activity and modifies neuronal synapse and energy production processes.

Mosquito borne diseases are on the rise because of their fast spread worldwide and the lack of effective treatments. Here we are focusing on the development of a novel anti-malarial and virucidal agent with biocidal effects also on its vectors. We have synthesized a new quinoline (4,7-dichloroquinoline) derivative which showed significant larvicidal and pupicidal properties against a malarial and a dengue vector and a lethal toxicity ranging from 4.408 µM/mL (first instar larvae) to 7.958 µM/mL (pupal populations) for Anopheles stephensi and 5.016 µM/mL (larva 1) to 10.669 µM/mL (pupae) for Aedes aegypti. In-vitro antiplasmodial efficacy of 4,7-dichloroquinoline revealed a significant growth inhibition of both sensitive strains of Plasmodium falciparum with IC50 values of 6.7 nM (CQ-s) and 8.5 nM (CQ-r). Chloroquine IC50 values, as control, were 23 nM (CQ-s), and 27.5 nM (CQ-r). In vivo antiplasmodial studies with P. falciparum infected mice showed an effect of 4,7-dichloroquinoline compared to chloroquine. The quinoline compound showed significant activity against the viral pathogen serotype 2 (DENV-2). In vitro conditions and the purified quinoline exhibited insignificant toxicity on the host system up to 100 µM/mL. Overall, 4,7-dichloroquinoline could provide a good anti-vectorial and anti-malarial agent.

Although there are existing vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), new COVID-19 cases are increasing due to low immunization coverage and the emergence of new variants. For this reason, new drugs to treat and prevent severe COVID-19 are needed. Here, we provide four different FDA-approved drugs against SARS-CoV-2 proteins involved in the entry and replication process, aiming to identify potential drugs to treat COVID-19. We use the main protease (Mpro), the spike glycoprotein (S protein), and RNA-dependent RNA polymerase (RdRp) as protein targets for anti- SARS-CoV-2 drugs. In our constructed database, we selected different drugs against each target (Mpro, S protein, and RdRp) based on their common interactions with relevant residues involved in viral entry at the host cell and replication. Furthermore, their stability inside the binding pocket, as well as their predicted binding-free energy, allow us to provide new insight into the possible drug repurposing of viomycin (interacting with Mpro) due to its interactions with key residues, such as Asn 143, Glu 166, and Gln 189 at the same time as hesperidin (interacting with the S protein) is interacting with residues Tyr 449, Ser 494, and Thr 500, keeping inside the predicted binding pocket, as well as interacting with residues in different variants of concern. Finally, we also suggest nystatin and elvitegravir (interacting with RdRp) as possible drugs due to their stability within the predicted pocket along the simulation and their interaction with key residues, such as Asp 760, Asp 761, and Asp 618. Altogether our results provide new knowledge about the possible mechanism of the inhibition of viomycin, hesperidin, elvitegravir, and nystatin to inhibit the viral life cycle of SARS-CoV-2 and some of its variants of concern (VOC). Additionally, some iodide-based contrast agents were also found to bind the S protein strongly, i.e., iohexol (−58.99 Kcal/mol), iotrolan (−76.19 Kcal/mol), and ioxilan (−62.37 Kcal/mol). Despite the information we report here as the possible strong interaction between these contrast agents and the SARS-CoV-2′s S protein, Mpro, and RdRp, we believe that further investigation, including chemical modifications in their structures, are needed for COVID-19 treatment.

CRISPR-based genetic engineering tools aimed to bias sex ratios, or drive effector genes into animal populations, often integrate the transgenes into autosomal chromosomes. However, in species with heterogametic sex chromsomes (e.g. XY, ZW), sex linkage of endonucleases could be beneficial to drive the expression in a sex-specific manner to produce genetic sexing systems, sex ratio distorters, or even sex-specific gene drives, for example. To explore this possibility, here we develop a transgenic line of Drosophila melanogaster expressing Cas9 from the Y chromosome. We functionally characterize the utility of this strain for both sex selection and gene drive finding it to be quite effective. To explore its utility for population control, we built mathematical models illustrating its dynamics as compared to other state-of-the-art systems designed for both population modification and suppression. Taken together, our results contribute to the development of current CRISPR genetic control tools and demonstrate the utility of using sex-linked Cas9 strains for genetic control of animals.

The current study describes the effects of sub-lethal concentrations and constituent compounds (citral and geranyl acetate) of Cymbopogon flexuosus essential oil (EO) on the development of Aedes aegypti . We treated eggs with 6, 18, or 30 mg L −1 and larvae with 3 or 6 mg L −1 of EO and its major compounds (citral and geranyl acetate). Citral and geranyl acetate were evaluated at 18, 30, and 42 mg L −1 and compared with commercial growth inhibitors (diflubenzuron and methoprene). We measured larval head diameter, siphon length, and larval length. Finally, we examined concentrations of molt hormone (MH) and juvenile hormone III (JH III) using high-performance liquid chromatography coupled to mass spectrometry. All geranyl acetate concentrations decreased egg hatching, while EO altered molting among larval instars and between larvae and pupae, with an increase in the larval length (3 mg L −1 : 6 ± 0.0 mm; 6 mg L −1 : 6 ± 0.7 mm) and head width (3 mg L −1 : 0.8 ± 0 mm; 6 mg L −1 : 0.8 ± 0.0 mm) compared with the control group. We did not detect chromatographic signals of MH and JH III in larvae treated with C. flexuosus EO or their major compounds. The sub-lethal concentrations C. flexuosus EO caused a similar effect to diflubenzuron, namely decreased hormone concentrations, an extended larval period, and death.

To generate an impact on the suppression of diseases such as Zika, it is necessary that vector control activities converge in a smart system exclusive for this goal. Chemical compounds collected from natural sources could contribute to such a control system in a powerful way, because they contain multieffect molecules useful to design and develop future insecticides and repellents. Here, we present information focused on our understanding of the utility of molecules from natural sources to control mosquito populations, aiming to promote their use by those involved in the field of mosquito control. We aim to convey this information in a way that can be useful to both the specialist in the topic and those whose interest in the topic is to avoid the bites of urban mosquitoes like Aedes aegypti or Ae. albopictus.

Compounds having insecticidal activity can be used to control Aedes aegypti mosquitoes, a major worldwide vector, and several plants have a source of such molecules. A principal component analysis (PCA) was carried out to determine the criterion to select larvicidal metabolites. The insecticidal activity of seven selected metabolites by PCA was validated by determining its lethal concentrations 50 (LC50) by probit analysis. Six of the seven evaluated molecules presented LC50 values <100 ppm. The effects of these six molecules on acetylcholinesterase and the respiratory chain complexes of the mitochondria of Ae. aegypti were evaluated. Four metabolites presenting the highest inhibition effects on these targets were mixed in 11 different combinations, and the percentage of mortality of each mixture on Ae. aegypti larvae were determined. Secondary metabolites such as geranyl acetate, α-humulene, β-caryophyllene, geraniol, nerol, and n-octanol presented LC50 values under 100 ppm (44, 41, 48, 84, 87, and 98 ppm, respectively), whereas 1,8-cineole presented a LC50 value of 183 ppm. We found that, geranyl acetate, α-humulene, β-caryophyllene, nerol, n-octanol, and geraniol inhibited at least one of the six targets with an efficiency between 25 and 41%. Overall, the evaluation of the different mixtures revealed a synergistic effect between geranyl acetate and geraniol, and an antagonistic effect between α-humulene and β-caryophyllene compounds.

Diferentes estudios han evaluado la actividad biocida de aceites esenciales (AEs) en larvas de mosquitos de importancia médica. Sin embargo, son limitadas las investigaciones que analizan los efectos de los AEs en todos los estadíos del ciclo de vida de Aedes aegypti. Este estudio evalúa la actividad biológica del AE de Salvia officinalis frente a Ae. aegypti. Se evaluó la actividad ovicida a concentraciones de 1, 5, 37 y 50 mg.L-1 en huevos de 0-12 h y huevos de 0-72 h. La actividad larvicida, pupicida y adulticida fue evaluada a concentraciones exploratorias (CE) y múltiples. Para la actividad repelente se empleó una CE de 1.000 mg.L-1 en intervalos de 0-2 min y de 2-15 min de exposición en antebrazos de voluntarios. La actividad disuasiva de oviposición se estimó a CE de 5, 50 y 200 mg.L-1. El AE causó malformaciones en embriones y alteración de las larvas. La mayor actividad larvicida fue a 63 y 76 mg.L-1 (27 ± 13,4 y 37 ± 18,6 %) a 24 h. La mayor mortalidad pupicida fue a 310 y 390 mg.L-1 (89 ± 1,53 and 100 ± 0 %) a las 48 h. La mortalidad adulticida a 300 mg.L-1 fue de 57,5 ± 0 % y el porcentaje de repelencia fue de 42 ± 4,7 %. La acción disuasiva a 200 mg.L-1 fue de 97 ± 4,81 %, con un índice de actividad de ovipostura de -0,94. S. officinalis mostró un efecto biocida en embriones y mortalidad de pupas y adultos, lo que revela que tiene un uso potencial en programas de control focalizados en estos estadios de desarrollo.