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PURPOSE: Rhipicephalus (Boophilus) microplus is one the most significant ectoparasite in cattle farming in tropical and subtropical regions, causing problems to livestock health worldwide. The control of this ectoparasite primarily relies on the use of synthetic acaricides. However, the emergence of acaricide resistance has stimulated the search for new control alternatives, including phytocompounds with acaricidal and insecticidal potential. The aim of this study was to evaluate the acaricidal potential of Lavandula dentata essential oil against the engorged females of R. (B.) microplus. METHODS: Engorged females were obtained from infested bovines in dairy farms in Pernambuco, Brazil. L. dentata essential oil was extracted, and adult immersion test assays were performed using the following oil concentrations: 0.2%, 0.4%, 0.6%, 0.8%, and 1%. RESULTS: L. dentata essential oil at a concentration of 1% was lethal to all engorged females, and concentrations of 0.6% and 0.8% caused mortality of 98.6% and 99.1%, respectively. These concentrations disrupted the reproductive capacity of engorged females, reducing oviposition by more than 90% and preventing egg hatching by over 87%. CONCLUSION: The data revealed that L. dentata essential oil possesses effective pharmacological properties against R. (B.) microplus and could be used for tick control following in vivo evaluation, thus contributing to mitigating the negative impacts of synthetic acaricide use.

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Both palm weevils, the South American (Rhynchophorus palmarum) (SAPW) and the red palm weevil (R. ferrugineus, RPW), are present in South America, affecting commercial, ornamental, and native palms. These pests oviposit and thrive on selected Arecaceae. R. palmarum mainly infests coconut (Cocos nucifera), oil palms (Elaeis guineensis), and other ornamental and native palms in America, causing a significant social impact on growers. The weevils fulfill a significant ectosymbiotic macro- and microorganism role in the first period of larval development, worsening the damage which, during this period, is not yet apparent. Palm protection in the Brazilian context suggests the use of indigenous agents for microbiological biocontrol. This research identifies three Brazilian Beauveria bassiana isolates: CVAD01, CVAD02, and CVAD06. The results suggest that the strain's impact on R. palmarum can also be compared with that of the commercial strain Beauveria bassiana. Phylogenetic analysis allowed the delimitation of species of Beauveria (Hypocreales). Pathogenicity tests caused significant mortality in R. palmarum. The isolates CVAD01, CVAD02, and CVADO6 showed high pathogenicity between 7 and 21 days, with mortality rates between 90 and 100%, suggesting that they may be effective biological control agents of R. palmarum in the field when used, within available means, to mitigate the impact of R. palmarum and R. ferrugineus in South America.

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Mosquitoes of the Aedes genus are responsible for transmitting many vector-borne viral diseases worldwide. Hundreds of thousands of people die annually from vector-borne diseases, including West Nile fever, dengue, tick-borne diseases, yellow fever, chikungunya, Rift Valley fever, and Zika. Billions of people are at the risk of infection on all continents, which is a cause of international concern. Therefore, new vector-control methods are essential for mitigating these illnesses. The bioactive hydrocarbons isolated from Xylopia langsdorfiana St. Hilaire & Tulasne are trachylobanes, a rare class of diterpenes found in the n-hexane fraction of the stem and leaf ethanolic extracts. These were tested against Ae. aegypti fourth-instar larvae over 48 h of exposure, with LC50 values ranging from 19.84 to 72.9 µg/mL, comparable to that of the positive control. The findings highlight the potential of Xylopia langsdorfiana St. Hilaire & Tulasne metabolites for controlling the main vectors of arthropod-borne viruses.

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Cassava is an essential tuber crop used to produce food, feed, and beverages. Whitefly pests, including Aleurothrixus aepim (Goeldi, 1886) (Hemiptera: Aleyrodidae), significantly affect cassava-based agroecosystems. Plant odours have been described as potential pest management tools, and the cassava clone M Ecuador 72 has been used by breeders as an essential source of resistance. In this study, we analysed and compared the volatile compounds released by this resistant clone and a susceptible genotype, BRS Jari. Constitutive odours were collected from young plants and analysed using gas chromatography-mass spectrometry combined with chemometric tools. The resistant genotype released numerous compounds with previously described biological activity and substantial amounts of the monoterpene (E)-ß-ocimene. Whiteflies showed non-preferential behaviour when exposed to volatiles from the resistant genotype but not the susceptible genotype. Furthermore, pure ocimene caused non-preferential behaviour in whiteflies, indicating a role for this compound in repellence. This report provides an example of the intraspecific variation in odour emissions from cassava plants alongside information on odorants that repel whiteflies; these data can be used to devise whitefly management strategies. A better understanding of the genetic variability in cassava odour constituents and emissions under field conditions may accelerate the development of more resistant cassava varieties.

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INTRODUCTION: The present work identified and compared intracellular metabolites and metabolic networks in mycelial cultures of Lasiodiplodia theobromae grown under 12 natural light and 24 hours' dark using a 1 H NMR-based metabolomics approach. MATERIALS AND METHODS: Fungal cultures were grown in potato dextrose media, and metabolites were extracted by sonication with sodium phosphate-buffered saline (pH = 6.0, 10% D2O, 0.1 mM TSP) from mycelium samples collected every week over four weeks. RESULTS: Multivariate analyses revealed that the light exposure group showed a positive correlation within beta-hydroxybutyrate, acetoacetate, acetone, betaine, choline, glycerol, and phosphocholine. On the other hand, phenyl acetate, leucine, isoleucine, valine, and tyrosine were positively correlated with dark conditions. Light favored the oxidative degradation of valine, leucine, and isoleucine, leading to the accumulation of choline, phosphocholine, betaine, and ketone bodies (ketogenesis). Ketogenesis, gluconeogenesis, and the biosynthesis of choline, phosphocholine, and betaine, were considered discriminatory routes for light conditions. The light-sensing pathways were interlinked with fungal development, as verified by the increased production of mycelia biomass without fruiting bodies and stress signaling, as demonstrated by the increased production of pigments.

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Tyrosine metabolism has an intense role in the synthesis of neurotransmitters. Our study used an untargeted, sportomics-based analysis of urine samples to investigate changes in metabolism during a soccer match in 30 male junior professional soccer players. Samples were collected before and after the match and analyzed using liquid chromatography and mass spectrometry. Results showed significant changes in tyrosine metabolism. Exercise caused a downregulation of the homogentisate metabolites 4-maleylacetoacetate and succinylacetone to 20% (p = 4.69E-5) and 16% (p = 4.25E-14), respectively. 4-Hydroxyphenylpyruvate, a homogentisate precursor, was found to be upregulated by 26% (p = 7.20E-3). The concentration of hawkinsin and its metabolite 4-hydroxycyclohexyl acetate increased ~six-fold (p = 1.49E-6 and p = 9.81E-6, respectively). Different DOPA metabolism pathways were also affected by exercise. DOPA and dopaquinone increased four-to six-fold (p = 5.62E-14 and p = 4.98E-13, respectively). 3-Methoxytyrosine, indole-5,6-quinone, and melanin were downregulated from 1 to 25%, as were dopamine and tyramine (decreasing to up to 5% or 80%; p= 5.62E-14 and p = 2.47E-2, respectively). Blood TCO2 decreased as well as urinary glutathione and glutamate (40% and 10% respectively) associated with a two-fold increase in pyroglutamate. Our study found unexpected similarities between exercise-induced changes in metabolism and the inherited disorder Hawkinsinuria, suggesting a possible transient condition called exercise-induced hawkinsinuria (EIh). Additionally, our research suggests changes in DOPA pathways may be involved. Our findings suggest that soccer exercise could be used as a model to search for potential countermeasures in Hawkinsinuria and other tyrosine metabolism disorders.

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As reformas neoliberais promoveram transformações no ensino superior. Nesse contexto, diversas instituições aderiram ao Programa de Apoio a Planos de Reestruturação e Expansão das Universidades Federais (REUNI). Isto, contudo, se deu sem as contrapartidas necessárias. O propósito da investigação, assim, foi compreender os impedimentos ao poder de agir de docentes que atuavam em um campus estruturado a partir do REUNI. Adotou-se o referencial da Clínica da Atividade. Participaram do estudo três docentes, duas mulheres e um homem, que atuavam em cursos de graduação e pós-graduação. Em uma perspectiva histórico-desenvolvimentista, foram realizadas entrevistas a partir de imagens que representavam elementos do contexto laboral. Utilizou-se análise construtivo-interpretativa. Dentre os resultados, viu-se intensificação do trabalho promovida pela atuação em cursos de pós-graduação e por atividades invisibilizadas; desprofissionalização associada ao desempenho de atividades alheias ao fazer docente; estrutura física inadequada; carga de trabalho elevada; pressões para o cumprimento de prazos; uso do espaço doméstico para o trabalho; e invasão do tempo livre. Os achados podem nortear ações de promoção da saúde docente e dar balizas para a discussão sobre as melhorias dos contextos de trabalho.

Neoliberal reforms promoted transformations in higher education. In this context, several institutions joined the Support Program for Restructuring and Expansion Plans of Federal Universities (REUNI). This happened without the necessary counterparts. The purpose of the investigation was to understand the impediments to the power to act of professors who worked in a campus structured from the REUNI. The reference of the Clinic of Activity was adopted. Three professors participated in the study, two women and one man, who worked in undergraduate and graduate courses. From a historical-developmental perspective, interviews were carried out based on images that represented elements of the work context. Constructive-interpretative analysis was used. Among the results, it was seen the intensification of work promoted by the performance in postgraduate courses and by invisible activities; de professionalization associated with the performance of activities outside the teaching profession; inadequate physical structure; high workload; pressure to meet deadlines; use of domestic space for work and invasion of free time. The findings can guide actions to promote teachers' health and provide guidelines for the discussion on improvements in work contexts.

Las reformas neoliberales impulsaron transformaciones en la educación superior. En ese contexto, varias instituciones se adhirieron al Programa de Apoyo a los Planes de Reestructuración y Expansión de las Universidades Federales (REUNI). Esto sucedió sin las contrapartes necesarias. La investigación tuvo como objetivo comprender los impedimentos al poder de actuar de los profesores que actuaban en un campus estructurado a partir de lo REUNI. Se adoptó la referencia de la Clínica de la Actividad. Participaron del estudio tres profesores, dos mujeres y un hombre, que actuaban en cursos de pregrado y posgrado. Desde una perspectiva histórica e de desarrollo, se realizaron entrevistas a partir de imágenes que representaban elementos del contexto de trabajo. Se utilizó el análisis constructivo-interpretativo. Entre los resultados, se vio la intensificación del trabajo promovida por la actuación en cursos de posgrado y por actividades invisibles; desprofesionalización asociada al desempeño de actividades ajenas a la docencia; estructura física inadecuada; alta carga de trabajo; presión para cumplir los plazos; uso del espacio doméstico para el trabajo e invasión del tiempo libre. Los hallazgos pueden orientar acciones para promover la salud de los docentes y proporcionar pautas para la discusión sobre mejoras en los contextos de trabajo.

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A magnetic graphite-epoxy composite (m-GEC) electrochemical sensor is presented based on magnetic imprinted polymer (mag-MIP) to determine homocysteine (Hcy). Mag-MIP was synthesized via precipitation polymerization, using functionalized magnetic nanoparticles (Fe3O4) together with the template molecule (Hcy), the functional monomer 2-hydroxyethyl methacrylate (HEMA), and the structural monomer trimethylolpropane trimethacrylate (TRIM). For mag-NIP (magnetic non-imprinted polymer), the procedure was the same in the absence of Hcy. Morphological and structural properties of the resultant mag-MIP and mag-NIP were examined using TEM, FT-IR, and Vibrating Sample Magnetometer. Under optimized conditions, the m-GEC/mag-MIP sensor showed a linear range of 0.1-2 µmol L-1, with a limit of detection (LOD) of 0.030 µmol L-1. In addition, the proposed sensor responded selectively to Hcy compared to several interferents present in biological samples. The recovery values determined by differential pulse voltammetry (DPV) were close to 100% for natural and synthetic samples, indicating good method accuracy. The developed electrochemical sensor proves to be a suitable device for determining Hcy, with advantages related to magnetic separation and electrochemical analysis.

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Schinus terebinthifolius Raddi has been extensively studied due to its antioxidant, anti-inflammatory and antibiotic properties. Recently, its seeds have been tested against some insect pests as an insecticide, repellent and antifungal agent. Microencapsulation by spray-drying is widely used in the food and drug industries, as well as in the microencapsulation of essential oils, since it protects the oils against several effects, such as oxidation and thermal degradation, thus optimising its use. The aim was to microencapsulate S. terebinthifolius essential oil by spray-drying maltodextrin and arabic gum as encapsulating agents and SiO2 as a colloidal adjuvant. The morphology of the microcapsules was analysed by scanning electron microscopy (SEM), which evidenced mainly regular spherical-shaped particles with sizes between 5 and 10 µm. The thermal stability was studied by thermogravimetric analysis-differential scanning calorimetry (TGA-DSC), and the microcapsules were stable at temperatures up to 200°C. The microencapsulating agents and the spray-drying technique produced microcapsules capable of protecting the essential oil against external effects, such as thermal degradation.

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Sand flies are dipterans of medical importance, as some species are vectors of American visceral leishmaniasis (AVL). The municipality of João Pessoa (Paraíba, northeastern Brazil), is an endemic region for AVL, having high rates of human and canine cases. The main objective was to evaluate the sand fly fauna among forest fragments and built areas, and its relationship with environmental conditions. HP light traps were placed in the studied areas from March 2019 to July 2021. A total of 2141 specimens of phlebotomines were captured, comprising nine genera and ten species. Temperature and humidity were significant and positive only in built areas. The diversity composition among forest fragments and built areas was different and the AVL vector, Lutzomyia longipalpis, was the most prevalent species in built areas. The study showed that the built areas present differences in their richness and diversity of sand flies in relation to forest fragments, concluding that the conservation of forest areas, even if urban fragments, favors the diversity of phlebotomine species.

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Cecropia pachystachya Tréc., popularly known as embaúba, belongs to the Cecropiaceae family and is used by the native population in the treatment of bronchitis, asthma, high blood pressure, fever, and as a diuretic. The pharmacological actions including anti-inflammatory, antioxidant, cardiotonic and sedative were previously reported. The objective of this study was to (1) isolate and identify bioactive compounds extracted from the ethanolic extract of C. pachystachya roots (ERCP), as well as (2) verify the affinity of these metabolites with the enzymes 5-lipoxygenase (5-LOX) and α-1-antitrypsin through in silico tests. Isolation and/or identification were performed using GC-MS, HPLC, Infrared (IR), and nuclear magnetic resonance (NMR) techniques. After isolation and identification of the active compounds, these substances were subjected to the in silico investigation that proceeded by performing PreADMET simulations and molecular docking calculations. The bioactive compounds identified were 1-(+)-ascorbic acid 2,6-dihexadecanoate, ethyl hexadecanoate, ethyl (9E,12E)-octadec-9,12-dienoate, ethyl (Z)-octadec-9-enoate and ethyl octadecanoate by GC-MS; chlorogenic acid, catechin, epicatechin, syringaldehyde by HPLC; ß-sitosterol, sitostenone, beccaridiol, tormentic acid, lupeol, α- and ß-amyrin by classical chromatography, IR, 1H and 13C NMR techniques. The ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties were determined for each bioactive compound. Tormentic acid demonstrated a greater affinity for 5-LOX enzyme while sitostenone demonstrated a higher affinity for the α-1-antitrypsin enzyme. Our findings demonstrated a diverse range of secondary metabolites isolated from C. pachystachya that showed relevant interactions with the enzymes 5-LOX and α-1-antitrypsin. Thus, "embaúba" may be employed in in vivo experimental studies as a form of alternative treatment for chronic lung diseases.Abbreviations: ADT: Autodock Tools; BBB: Blood-brain barrier; CaCo2: Human colonic adenocarcinoma cells; CC: Classic/open Column; TLC: Thin Layer Chromatography; CD40: Differentiation Cluster 40; CENAUREMN: Centro Nordestino de Aplicação e Uso da Ressonância Magnética Nuclear; GC-MS: Gas Chromatography coupled to mass spectrometry; HPLC: High-Perfomance Liquid Chromatography; CYP2C9, CYP2C19, CYP2D6 and CYP3A4: Cytochrome P450 isoenzymes; COPD: Chronic Obstructive Pulmonary Disease; DRX-500: X-Ray Diffraction - 500; ERCP: Ethanolic extract of the roots of C. pachystachya; FAPEPI: Fundação de Amparo à Pesquisa do Piauí; HIA: Human Intestinal Absorption; IR: Infrared; Ki: Inhibition constant; 5-LOX: 5-Lipoxygenase; mM: miliMolar; nM: nanoMolar; OECD423: acute toxic class method; PDB: Protein Data Bank; P-gP: P-glycoprotein; PM2,5: Small inhalable particles 2,5; PPB: Plasm Protein Binding; PreADMET: Prediction Absorption, Distribution, Metabolization, Excretion and Toxicity; NMR: Nuclear Magnetic Resonance; +S9: with metabolic activation; -S9: no metabolic activation; SisGen: Sistema Nacional de Gestão de Patrimônio Genético e do Conhecimento Tradicional Associado; RT: Retention time; TA100: Ames test with TA100 cells line; TA1535: Ames test with cells of the TA1535 cell line; UESPI: State University of Piauí; V79: lung fibroblast cells; ΔG: Gibbs free energy (Kcal/mol); µM: microMolar.

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A novel baculovirus observed to infect Automeris liberia (Cramer) (bullseye moth) is here described. Caterpillars of A. liberia with symptoms of viral infection were collected from African oil palm plantations in Tailândia, PA, Brazil. Macerated caterpillars were then offered to caterpillars of Automeris cinctistriga (Felder & Rogenhoper), leading to viral symptoms and death before pupation. A transmission electron microscope was used for virus ultrastructural identification. The presence of viral occlusion bodies (OBs) containing multiple nucleocapsids was observed and such features are compatible with Alphabaculovirus (Baculoviridae). Molecular detection by PCR with primers for polyhedrin gene (polh) and for late expression factor-8 gene (lef-8), confirmed that this isolate belonged to Alphabaculovirus genus. To our knowledge, this is the first record of a baculovirus isolated from or associated to Automeris. The name Automeris liberia nucleopolyhedrovirus (AuliNPV) is proposed for the new virus.

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The aim of this study was to analyze the production patterns present in rural properties producing cattle in the micro-regions that make up the state of Pará. Exploratory Factor Analysis (EFA) was applied to identify the patterns, and these data are used to evaluate correlation between the heterogeneity of rural properties and the environmental impact on the identified patterns. The theoretical contribution is based on discussions on global impacts of food production and environmental sustainability and the impacts of livestock production systems in Brazil and the Amazon. Survey data were taken from the 2017 Agricultural Census, available for the 144 municipalities in the state, and pooled into 22 micro-regions. Three patterns of rural properties were identified: the first related to conservation management practices and called transition management; the second highlights aspects associated with information technology and communication (ICT) and productivity called technical productive efficiency; the third indicates the importance of social organization and access to information called social participation. With these patterns, it was possible to develop the Traditional Performance Indicator (TPI), in which the micro-regions of São Félix do Xingu, Itaituba and Conceição do Araguaia were those with the highest values of this indicator, water protection practices are present in the properties, however, in precarious conditions, and conservation practices are rarely used. The correlation between heterogeneity, measured by the size of pasture area in each microregion, and the TPI is positive, strong and significant. In this transition context, public policies are essential to provide access to infrastructure, credit and good animal health and biotechnology practices.(AU)

O objetivo deste estudo foi analisar os padrões de produção presentes nos estabelecimentos rurais produtores de gado bovino nas microrregiões que formam o estado do Pará. Foi aplicada a técnica estatística de Análise Fatorial Exploratória (AFE) para identificar os padrões, e com esses dados avaliar a correlação entre a heterogeneidade das propriedades rurais produtoras e o impacto ambiental nos padrões identificados. O aporte teórico está ancorado nas discussões sobre os impactos globais da produção de alimentos e a sustentabilidade ambiental e os impactos da pecuária no Brasil e na Amazônia. Os dados da pesquisa foram extraídos do Censo Agropecuário de 2017, disponíveis para os 144 municípios do estado, e agregados em 22 microrregiões. Foram identificados três padrões de estabelecimentos rurais: o primeiro relacionado as práticas de gestão conservacionistas e denominado de gestão em transição; o segundo destaca aspectos associados a tecnologia de informática e comunicação (TIC) e a produtividade denominado de eficiência técnica produtiva; o terceiro indica a importância da organização social e o acesso a informação denominado de participação social. Com os resultados desses padrões foi possível gerar o Indicador de Desempenho Tradicional (IDT), em que as microrregiões de São Félix do Xingu, Itaituba e Conceição do Araguaia foram aquelas com maior nível desse indicador, as práticas de proteção das águas se fazem presente nas propriedades, porém, em condições precárias, e as práticas conservacionistas são pouco empregadas. A correlação entre a heterogeneidade, medida pelo tamanho da área de pasto em cada microrregião, e o IDT é positiva, forte e significativa. Nesse contexto de transição, as políticas públicas são essenciais para proporcionar acesso a infraestrutura, crédito e boas práticas de saúde animal e biotecnologia.(AU)

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Coupling several natural and synthetic lures with aggregation pheromones from the palm weevils Rhynchophorus palmarum and R. ferrugineus reveals a synergy that results in an increase in pest captures. The combined attraction of pure pheromones, ethyl acetate, and decaying sweet and starchy plant tissue increases the net total of mass-trapped weevils. The 2018 entrance of the red palm weevil (RPW) into South America has threatened palm-product income in Brazil and other neighboring countries. The presence of the new A1 quarantine pest necessitates the review of all available options for a sustainable mass-trapping, monitoring, and control strategy to ultimately target both weevils with the same device. The effective lure-blend set for the mass-trapping system will attract weevils in baiting and contaminating stations for entomopathogenic fungi that the same weevils will spread.

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The species of the Culicoides genus are hematophagous, and some of them are vectors of important human and animal diseases. This group of insects is distributed worldwide, varying according to local species. Knowledge of the geographic distribution of specific species is crucial for the development and implementation of control strategies. The aim of this work was to investigate the occurrence of Culicoides in the state of Alagoas in northeast Brazil. Midges were captured with CDC light traps, and their identification and morphological analyses were performed by the Ceratopogonidae Collection of the Oswaldo Cruz Foundation (FIOCRUZ/CCER) in Rio de Janeiro, Brazil. Morphological analyses were performed using the key to Culicoides from the guttatus group and comparison with other deposited specimens. DNA sequencing, genetic analysis and comparison with sequences in the Genbank database, confirmed the identification of the flies as Culicoides insignis. This was the first formal report of C. insignis being found in Alagoas.

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The 9-azabicyclo[3.3.1]nonane ring system is present in several insect- and plant-derived alkaloids. (-)-Adaline (1) and (+)-euphococcinine (2), found in secretions of Coccinelid beetles, and (+)-N-methyleuphococcinine (3), isolated from the Colorado blue spruce Picea pungens, are members of this alkaloid family. Their unique bicyclic system with a quaternary stereocenter, and the potent biological activity exerted by these homotropane alkaloids, make them attractive synthetic targets. This work aims briefly to review the chemical ecology of Adalia bipunctata and the recent methodologies to obtain adaline (1), euphococcinine (2), and N-methyleuphococcinine (3).

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The contamination of bodies of water by potentially hazardous elements has in recent decades become an environmental problem that poses serious risks to humans, fauna, flora and microbiota, compromising the quality of life of the present ecosystem. Therefore, effluents must be properly treated in a legally acceptable manner before their disposal in the environment. With this in mind, adsorption presents itself as an inexpensive efficient technique for the removal of potentially hazardous elements from effluents with excellent adsorption capacities when natural adsorbents are used. In this study, fava d'anta fodder was used in its crude and alkalinized form to remove Cu(II) and Pb(II) ions. Equilibrium studies were carried out using adsorption isotherms in batch systems with mono- and multi-elementary systems containing the two ions. The Langmuir and Freundlich models were applied to the isotherm studies, with the ions being better suited to the Langmuir model, with maximum adsorption capacities of 24.45 mg g-1 and 68.49 mg g-1 (crude form) and 11.12 mg g-1 and 35.34 mg g-1 (alkalinized form) in the mono-elementary system for Cu(II) and Pb(II) ions, respectively.

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Insect cuticle lipids are involved in various types of chemical communication between species, and reduce the penetration of insecticides, chemicals, and toxins, as well as provide protection against the attack of microorganisms, parasitic insects, and predators. Ecological studies related to the insect Rhynchophorus palmarum are well-known; however, very little is known about its resistance mechanisms, which includes its lipid composition and its importance, specifically the cuticle layer. This study aimed to characterize the cuticle and internal lipid compounds of the male and female R. palmarum adult insects and to evaluate the presence of antimicrobial activity. We performed by gas chromatography coupled to mass spectrometry (GC-MS) analyzes of lipid extracts fractions and we identified 10 methyl esters of fatty acids esters of C14 to C23, with variation between the sexes of C22:0, C21:0, present only in male cuticle, and C20:2 in female. The lipid content of this insect showed relevant amount of C16:1, C18:1, and C18:2. The antimicrobial activity of the cuticular and internal fractions obtained was tested, which resulted in minimum inhibitory concentrations between 12.5 and 20 µg/ml against Gram-positive bacteria (Staphylococcus epidermidis, Enterococcus faecalis), Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia), and fungal species (Candida albicans e Candida tropicalis). The antimicrobial effect of the R. palmarum cuticle open perspectives for a new source to bioinsecticidal strategies, in addition to elucidating a bioactive mixture against bacteria and fungi.

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The giant sugarcane borer Telchin licus (Drury, 1773) (Lepidoptera: Castniidae) is a day-flying moth pest of sugarcane, pineapples and bananas. To better understand the chemical communication in this species, we examined the morphology of its olfactory system and the chemical composition of its body parts. The ventral surface of the clubbed antennae of T. licus has six morphological types of sensilla: sensilla trichodea, basiconica, chaetica, squamiforma, coeloconica, and auricillica. The telescopic ovipositor shows no evidence of a sexual gland, or female-specific compounds. On the other hand, the midleg basitarsus of males releases (E,Z)-2,13-octadecadienol and (Z,E)-2,13-octadecadienol, which are electroantennographically active in both sexes. These compounds are known female sex pheromones in the Sesiidae family and are male-specific compounds in another castniid moth, although further investigations are necessary to elucidate their ecological role in the Castniidae family.

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BACKGROUND: The cashew stem borer Anthistarcha binocularis (Meyrick) is a major pest in cashew orchards in Brazil. The damage caused by the larvae results in economic losses, and the available chemical control is not suitable because of the endophytic nature of A. binocularis. The identification of the A. binocularis sex pheromone could provide novel applications for the detection and monitoring of this species. RESULTS: Two compounds from female sex gland extracts elicited electrophysiological responses on male antennae. They were identified as dodec-6-en-1-ol and dodec-6-en-1-yl acetate by gas chromatography-mass spectrometry. E/Z stereoisomers of both compounds were synthesized, and the electroantennograms for the synthetic compounds showed the strongest responses for the (E)-stereoisomers of the alcohol and acetate. In a field trial, the E6-12:OH/E6-12:OAc mixture attracted male A. binocularis, whereas the Z6-12:OH/Z6-12:OAc mixture attracted no specimens. CONCLUSIONS: The bioactive compounds from the sex pheromone of A. binocularis have been identified as a mixture of two previously unidentified pheromone compounds: E6-12:OH and E6-12:OAc. The mixture of both compounds was attractive to males in preliminary field experiments, and this study is the first report of Δ6-unsaturated monoenyl pheromone compounds in Lepidoptera. © 2019 Society of Chemical Industry.

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