Resumo Croton argyrophylloides Muell. Arg., pertencente à família Euphorbiaceae, conhecida popularmente como marmeleiro prateado e sacatinga, é um vegetal do bioma caatinga comumente encontrado no Nordeste do Brasil. O presente trabalho teve como objetivo avaliar a atividade antioxidante da espécie. O estudo fitoquímico foi realizado por meio de análise qualitativa dos constituintes químicos e determinação quantitativa do teor de fenóis totais pelo teste de Folin-Ciocalteu. Os testes antioxidantes qualitativos e quantitativos foram realizados pelo método do DPPH (2,2 difenil-1- picril-hidrazila) e redução do ferro (FRAP). A concentração inibitória mínima (CIM) foi determinada por microdiluição em placas de 96 poços. O extrato etanólico das folhas de C. argyrophylloides apresentou ação antioxidante no teste DPPH quantitativo com uma significativa bioatividade de 84.70 AAO% em 500 µg/mL, apresentando um CE50 de 236.79. O teor de compostos fenólicos totais, foi de 946,06 mg equivalentes de ácido gálico/g de amostra, e de flavonoides totais de 58,11 mg equivalentes de quercetina/g da amostra, o valor encontrado para FRAP foi de 15294,44 µM Trolox/g da amostra e de ABTS foi 718 μM Trolox da amostra. A prospecção dos constituintes químicos das folhas de C. argyrophylloides revelou a presença dos principais compostos que caracterizam a atividade antioxidante e foi possível comprovar pelo método de DPPH que há atividade antioxidante na amostra analisada, além de demonstrar um resultado significativo de teor de compostos fenólicos e teor de flavonoides totais na espécie e o que corrobora com a atividade antioxidante da amostra vegetal. Os extratos das folhas apresentaram halos de inibição de crescimento de 10 e 12mm frente a Staphylococcus aureus ATCC 25923.

Abstract Croton argyrophylloides Muell. Arg., from the Euphorbiaceae family, popularly known as marmeleiro prateado or sacatinga, is a plant from the Caatinga biome commonly found in Brazil’s northeastern region. The present study aimed to evaluate the antioxidant activity of the species. The phytochemical study was performed through qualitative analysis of chemical constituents and quantitative determination of the total phenol content through the Folin-Ciocalteu test. The qualitative and quantitative antioxidant tests were performed using the DPPH method (2.2 diphenyl-1-picryl hydrazil) and ferric reducing antioxidant power (FRAP). The minimum inhibitory concentration (MIC) was determined by microdilution in 96-well plates. The ethanolic extract of the leaves of C. argyrophylloides manifested antioxidant action in the quantitative DPPH test with a significant bioactivity of 84.70 AAO% in 500 µg/mL, with an EC50 of 236.79. The content of total phenolic compounds was 946.06 mg of gallic acid equivalents/g of sample, and total flavonoids was 58.11 mg of quercetin equivalents/g of sample, the result obtained for FRAP was 15294.44 µM Trolox/g of sample and ABTS was 718 μM Trolox of sample. The prospecting of the chemical constituents of the leaves of C. argyrophylloides revealed the presence of the main compounds that manifests the antioxidant activity and it was proven by the DPPH method that there is antioxidant activity in the analyzed sample, in addition to demonstrating a significant content of phenolic compounds and total flavonoid content in the species, which corroborates the antioxidant activity of the plant sample. The leaf extracts presented growth inhibition halos of 10 and 12 mm upon Staphylococcus aureus ATCC 25923.

The Brazilian Cerrado biome is considered one of the 25 hotspots worldwide that contain bioactive compounds due to its great biodiversity; however, the reduction of its native area over time due to the expansion of urbanization and agribusiness may have compromised knowledge of its biological variety. In this context, knowledge about Cerrado species can contribute to its biodiversity preservation. This study aims to describe the isolation, molecular architecture and theoretical calculations of the compound (3S,8S,9S,10R,13R,14S,17R)-17-[(2R,5R)-5 ethyl -6-methylheptan-2 yl]-10,13 dimethyl 2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro-1H cyclopenta[a]phenanthren-3 ol, extracted from the Brazilian Cerrado Miconia burchellii plant. The supramolecular arrangement was described by Hirshfeld surface analysis, demonstrating the intermolecular interactions in the crystalline packing. The structure-property relationship shows the electrostatic potential map analysis, which reveals that the oxygen region is susceptible to electrophilic attack, and the frontier molecular orbital confirmed the kinetic stability of this compound. This study represents another step forward in the knowledge of compounds with pharmacological and medicinal properties extracted from the Cerrado.

Abstract Coffea sp. is cultivated in many tropical countries. Brazil has always adopted intensive agricultural practices, but organic coffee farming is an alternative system based on the non-use of agrochemicals and the rational management of soils. Metabarcoding 16S analysis using next-generation sequencing has been developed to identify and compare the diversity of the Coffea arabica L. rhizospheric bacterial community in two farming areas in São Paulo, Brazil. Dourado uses conventional farming, while Ribeirão Corrente uses organic. We found broad taxonomic composition, with sequences from 24 phyla, 55 classes, 61 orders, 146 families, and 337genus. The three most abundant phyla were Proteobacteria (38.27%), Actinobacteria (15.56%), and Acidobacteria (16.10%). In organic farming, the top 3 were the family Sphingomonadaceae, order Rhizobiales, genus Nocardioides, and Gp6. The genus Gp2 and the phylum Candidatus Saccharibacteria were the most abundant OTUs exclusively present in conventional farming. In the organic farming practice, Proteobacteria, Actinobacteria, and Acidobacteria were also present among the exclusive OTUs; we also found OTUs belonging to Bacteroidetes, Firmicutes, and Verrucomicrobia. Our study indicates a positive effect of organic farming on microbial communities. Fertilization may directly affect soil microbiota, suggesting that a large and active microbial community low in functional diversity might not adapt to new climatic conditions. A diverse community could provide better resilience to environmental changes, improving the productivity of this important crop.

Resumo Coffea sp. é cultivada em muitos países tropicais. O Brasil sempre adotou práticas agrícolas intensivas, mas a cafeicultura orgânica é um sistema alternativo baseado na não utilização de agrotóxicos e no manejo racional dos solos. A análise Metabarcode 16S utilizando o sequenciamento de última geração foi desenvolvida para identificar e comparar a diversidade da comunidade bacteriana rizosférica de Coffea arabica L. em duas áreas de cultivo em São Paulo, Brasil. Dourado usa agricultura convencional, enquanto Ribeirão Corrente usa agricultura orgânica. Encontramos ampla composição taxonômica, com sequências de 24 filos, 55 classes, 61 ordens, 146 famílias e 337 gêneros. Os três filos mais abundantes foram Proteobacteria (38,27%), Actinobacteria (15,56%) e Acidobacteria (16,10%). Na agricultura orgânica, os 3 primeiros foram a família Sphingomonadaceae, ordem Rhizobiales, gênero Nocardioides e Gp6. O gênero Gp2 e o filo Candidatus Saccaribacteria foram as OTUs mais abundantes exclusivamente presentes na agricultura convencional. Na prática da agricultura orgânica, Proteobacteria, Actinobacteria e Acidobacteria também estiveram presentes entre as OTUs exclusivas; também encontramos OTUs pertencentes a Bacteroidetes, Firmicutes e Verrucomicrobia. Nosso estudo indica um efeito positivo da agricultura orgânica nas comunidades microbianas. A fertilização pode afetar diretamente a microbiota do solo, sugerindo que uma grande e ativa comunidade microbiana com baixa diversidade funcional pode não se adaptar às novas condições climáticas. Uma comunidade microbiana diversificada poderia proporcionar maior resiliência às mudanças ambientais, melhorando a produtividade desta importante cultura agrícola.

RESUMO: Deficiências minerais são importantes causas de perdas produtivas em criações de ruminantes, sobretudo em regiões semiáridas. Este trabalho teve como objetivo determinar as concentrações séricas de Na, K e Cl, além das concentrações salivares de Na e K em ovinos criados em uma região semiárida do Nordeste do Brasil e relatar a epidemiologia e os aspectos clínicos e patológicos de um surto de hiponatremia severa em ovinos. Para isso, amostras de soro e saliva de 55 ovinos foram coletadas em 6 diferentes fazendas da região. As concentrações de Na, K e Cl foram determinadas por teste colorimétrico, utilizando kits comerciais em analisador bioquímico semiautomático. As concentrações séricas médias variaram de 131,5±13,1mEq/L a 172,4±9,3mEq/L para Na, 6,28±1,3mEq/L a 13,9±1,4mEq/L para K e 91,6±54,8mEq/L a 113,6±1,5mEq/L para Cl. As concentrações salivares médias variaram de 119,4±9,5mEq/L a 161,8±15,2mEq/L para Na, 10,1±3,1mEq/L a 22,3±2,3mEq/L para K, e a razão Na: K variou de 6,0±1,3mEq/L a 11,8±4,1mEq/L. Esses resultados revelaram que a maioria dos ovinos criados nas fazendas desta região são marginalmente sódio deficientes. Em uma fazenda, os ovinos apresentavam um quadro clínico grave de deficiência de Na. Os principais sinais clínicos consistiam em apatia, avidez por sal, polidipsia, poliúria, tosse seca, inapetência, pica, fraqueza, dificuldade de se levantar e se locomover, emagrecimento e desidratação. À necropsia, o conteúdo ruminal estava geralmente compactado, dando ao conteúdo um aspecto de bolas de argila. Quatro ovelhas apresentaram hipertrofia das glândulas adrenais. Histopatologicamente, a zona glomerulosa apresentava-se espessa, com perda da arquitetura e desarranjo dos cordões celulares. As células epiteliais da zona glomerulosa e fasciculada eram piramidais, apresentavam citoplasma hipereosinofílico e continham núcleos hipercromáticos. Esses dados demonstram a ocorrência de deficiência de Na em diferentes graus em criações de ovinos no Estado de Pernambuco e evidencia a importância do fornecimento de NaCl para a prevenção de surtos de hiponatremia.

ABSTRACT: Mineral deficiencies are important causes of productive losses in ruminant farming, especially in semiarid regions. This study aimed to determine Na, K, and Cl serum concentrations, plus the salivary concentrations of Na and K in sheep raised in a semiarid region of Northeastern Brazil, and to report the epidemiology, clinical and the pathological aspects of an outbreak of hyponatremia in sheep. For this, serum and salivary samples of 55 sheep were collected in 6 different farms in the region. Na, K, and Cl concentrations were determined by colorimetric test, using commercial kits in a semi-automatic biochemical analyzer. The mean serum concentrations ranged from 131.5±13.1mEq/L to 172.4±9.3mEq/L for Na, 6.28±1.3mEq/L to 13.9±1.4mEq/L for K, and 91.6±54.8mEq/L to 113.6±1.5mEq/L for Cl. The mean salivary concentrations ranged from 119.4±9.5mEq/L to 161.8±15.2mEq/L for Na, 10.1±3.1mEq/L to 22.3±2.3mEq/L for K, and the ratio Na:K ranged from 6.0±1.3mEq/L to 11.8±4.1mEq/L. These results revealed that most sheep raised in the farms in this region are marginally depleted in sodium. In one farm, sheep had severe clinical signs of Na deficiency consisting of haggard appearance, craving for salt, polydipsia, polyuria, dry cough, inappetence, pica, weakness, difficulty to rise and move, severe emaciation, and dehydration. On autopsy, the ruminal content was generally impacted, giving to the content an aspect of clay balls. Four sheep presented hypertrophy of the adrenal glands. Histopathologically, the width of the zona glomerulosa was expanded, there was loss of the architecture and loss of adrenocortical cell cords. The epithelial cells in the zona glomerulosa and fasciculata were pyramidal, and contained hypereosinophilic cytoplasm and hyperchromatic nuclei. These data demonstrate the occurrence of Na deficiency in different degrees in sheep farms in the State of Pernambuco and highlight the importance of providing NaCl to avoid outbreaks of hyponatremia.

Resumo O interesse por espécies vegetais com ação antiviral tem crescido exponencialmente e algumas tem sido relatadas como possuídoras de propriedades anti-HIV. Essa pesquisa tem como objetivo realizar o fracionamento fitoquímico biodirecionado pela atividade antirretroviral das cascas do caule da espécie Lafoensia pacari. Trata-se de um estudo experimental in vitro e a metodologia envolve preparo do material vegetal, obtenção do extrato etanólico, fracionamento, purificação, identificação e quantificação das frações, extração ácido-base, ressonância magnética nuclear, teste de inibição da TR do HIV-1 e estudos de docking molecular. A partir do fracionamento biodirecionado pela atividade antirretroviral verificou-se uma maior atividade nas subfrações acetanólica. Com destaque para a subfração acetanólica neutros com 60,98% de inibição de TR e o ácido elágico com 88,61% de inibição de TR e ausência de citotoxicidade. Verificou-se com o teste de citotoxicidade em linhagem de macrófagos que a fração clorofórmica foi mais tóxica que a fração acetanólica. A análise do espectro J-resolvido na região aromática apresentou um simpleto em 7.48 e 6.93 ppm que foram identificados como ácido elágico e ácido gálico respectivamente. A enzima 5TIQ obteve melhor parâmetro de afinidade com o ligante ácido elágico que foi confirmado pelos espectros HSQC-1H-13C. O ácido gálico mostrou-se também favorável a formar interação com a enzima 5TIQ, sendo confirmado através do espectro HSQC-1H-13C. Através da avaliação do PreADMET verificou-se que o ácido elágico é uma molécula promissora pela sua atividade de inibição da TR e parâmetros farmacocinéticos e de toxicidade.

Abstract Interest in antiviral plant species has grown exponentially and some have been reported to have anti-HIV properties. This research aims to perform the bio-guided phytochemical fractionation by antiretroviral activity of Lafoensia pacari stem barks. This in vitro experimental study involved the preparation of plant material, obtention of ethanolic extract, fractionation, purification, identification and quantification of fractions, acid-base extraction, nuclear magnetic resonance, HIV-1 RT inhibition test and molecular docking studies. From the bio-guided fractionation by the antiretroviral activity there was a higher activity in the acetanolic subfractions, highlighting the acetate subfraction – neutrals with 60.98% of RT inhibition and ellagic acid with 88.61% of RT inhibition and absence of cytotoxicity. The macrophage lineage cytotoxicity assay showed that the chloroform fraction was more toxic than the acetate fraction. The analysis of the J-resolved spectrum in the aromatic region showed a singlet at 7.48 and 6.93 ppm which was identified as ellagic acid and gallic acid, respectively. The 5TIQ enzyme obtained better affinity parameter with the ellagic acid ligand, which was confirmed by the HSQC-1H-13C spectra. Gallic acid was also favorable to form interaction with the 5TIQ enzyme, being confirmed through the HSQC-1H-13C spectrum. From the PreADMET evaluation it was found that ellagic acid is a promising molecule for its RT inhibition activity and pharmacokinetic and toxicity parameters.

Ambuic acid (AA) is a highly-modified cyclohexenone and known as a promising inhibitor of quorum sensing in methicillin-resistant Staphylococcus aureus, and is thus a candidate as an antivirulence drug. This molecule is mainly produced by the species of Pestalotiopsis and, since its discovery twenty years ago, only a restricted amount of AA-derivatives have been described. Despite being a promising subject, methods for the analysis of modified AA-analogues via mass spectrometry remain unexplored. In order to adress this question, the marine fungus Pestalotiopsis sp. 4A11 associated with the ascidian Didemnum perlucidum was grown in a solid rice medium and its crude extract was chemically studied. From this extract, AA and 10-hydroxy ambuic acid (10-HAA) were isolated and identified using NMR spectroscopy with the aim of obtaining model compounds for the MS analysis. These served as reference compounds (seeds) to guide the dereplication of other AA-analogues via LC-MS/MS-based molecular networking. Based on the manual interpretation of the fragmentation pathways of the seeds and related compounds observed in the networks, six AA-derivatives were dereplicated in the extract. Furthermore, three analogues with unprecedented chemical formulas were proposed as putative unprecedented AA-derivatives. The fragmentation annotation proposed represents a fast and feasible method for characterizing AA-derivatives.

Resumo Embora atualmente exista um conjunto de estudos sobre aspectos ecológicos de algumas espécies de répteis e de anfíbios que ocorrem nas planícies costeiras arenosas brasileiras (incluindo os chamados habitats de “restinga” e de “campo nativo”), há relativamente poucas informações sobre a composição de espécies geralmente associada a esses ambientes. Durante 31 anos (1988-2019) de estudos herpetológicos realizados em restingas por nossa equipe de pesquisa do Laboratório de Ecologia de Vertebrados (Departamento de Ecologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brasil) nós estudamos comunidades de répteis e de anfíbios e realizamos diferentes estudos com métodos semelhantes em 70 localidades de dez diferentes Estados ao longo da costa brasileira. Nossas pesquisas resultaram em registros de 87 espécies de répteis (cinco tartarugas, dois crocodilianos, seis anfisbênios, 36 lagartos e 39 serpentes) de 24 famílias, e 77 espécies de anfíbios anuros de nove famílias. Estudamos vários tópicos de história natural sobre anuros e répteis, que resultaram na publicação de alguns estudos ecológicos específicos, especialmente em relação a algumas espécies, abrangendo ecologia populacional e de comunidades, forrageamento e dieta, horário de atividade de espécies, termorregulação, reprodução, uso do microhabitat e parasitismo por ecto e endoparasitas. Nossos resultados ao longo dessas três décadas também contribuíram para a descrição de quatro novas espécies de lagartos (Ameivula nativo, Glaucomastix littoralis, G. abaetensis e G. itabaianensis). Nossos estudos constituem uma importante contribuição para o conhecimento da ecologia de répteis e de anfíbios anuros nesses ecossistemas, bem como para a conservação dos ecossistemas de restinga. A lista de espécies apresentada neste estudo, com base em nossos registros de herpetofauna das planícies costeiras arenosas, fornece para muitas localidades ao longo da costa brasileira o conhecimento necessário sobre a ocorrência de espécies, incluindo a presença de espécies endêmicas e/ ou ameaçadas de extinção, que podem ser úteis para muitas ações de conservação.

Abstract Although currently there is already a set of studies regarding ecological aspects of some particular reptile and amphibian species living in Brazilian sandy coastal plains (including the so-called “restinga” and “campo nativo” habitats), there is comparatively few information on the species composition usually associated to these environments. During 31 years (1988-2019) of herpetological studies carried out in sandy coastal plains environments by our research team of the Laboratory of Vertebrate Ecology (Department of Ecology, Universidade do Estado do Rio de Janeiro, in Rio de Janeiro Brazil) we have surveyed reptile and amphibian communities and performed different studies with similar methods in 70 sites from 10 different states along the Brazilian coast. Our surveys resulted in records of 87 species of reptile (five turtles, two crocodylians, six amphisbaenians, 36 lizards and 39 snakes) from 24 families, and 77 species of anuran amphibians from nine families. We have studied multiple natural history topics for anurans and reptiles which resulted in the publication of some specific ecological studies, especially regarding some species, encompassing population and community ecology, foraging and feeding habits, species activity, thermoregulation, reproduction, use of microhabitats, and parasitism by ecto and endoparasites. Our results along these three decades have also contributed for the description of four new lizard species (Ameivula nativo, Glaucomastix littoralis, G. abaetensis and G. itabaianensis). Our studies constitute an important contribution to the knowledge of the ecology of anuran amphibians and reptiles in these ecosystems, as well as to the conservation of sandy coastal plains environment. The checklist presented in this study, based on our records of sandy coastal plains herpetofauna, provides for many localities along the Brazilian coast, the needed knowledge on species occurrence, including the presence of endemic and/or endangered species, which can be of value for many conservation actions.

In this work, we report the synthesis of three series of carbohydrate-based benzo[f]indole-4,9-diones and amino-1,4-naphthoquinone derivatives and evaluated their cytotoxic activity against eight human cancer cell lines. Several compounds showed a promising cytotoxic activity toward the tumor cell lines (half maximal inhibitory concentration (IC50) < 10.0 μM). The importance of the substitution pattern of the quinone derivatives on the antitumor activity was also discussed. 3-Carboethoxy-2-methyl-benzo[f]indole-4,9-dione derivatives were more cytotoxic than their parent compounds and amino-1,4-naphthoquinones. Unlike clinically useful anticancer agent doxorubicin, the majority of synthesized compounds did not exhibit any lytic effects against erythrocytes or normal human leukocytes.

The present work describes the chemical constituents of Odontadenia lutea (Vell.) Markgr. leaves and the toxicities of its extract and fractions against Atta sexdens rubropilosa Forel (Hymenoptera: Formicidae). Chromatographic procedures of the ethanolic extract resulted in the identification of the triterpene β-amyrin, the flavonoid rutin, two fatty acids palmitic and linolenic, and one glyceroglycolipid 3-O-(9,12,15-octadecatrienoyl)-glyceryl-β-D-galactopyranoside, which are known compounds, but they are described for the first time in the Odontadenia genus. The known triterpenes lupeol and α-amyrin were also identified. Structural identification of the compounds was performed by analysis of IR, ESI-MS, and 1D and 2D NMR spectra. The toxicity of its extract and fractions from O. lutea leaves was tested against leaf-cutting ants Atta sexdens rubropilosa Forel by employing ingestion bioassay procedures. The hexane fraction (2 mg mL-1) decreases the average survival of ants from sixteen to six days, causing 98% mortality on the 14th day and 100% at the end of the experiment.

Abstract Fifty-five watermelon accessions were inoculated in pots using Fusarium oxysporum f. sp. niveum chlamydospores in a completely randomized design with five replications. Among the 42 accessions that were resistant, twelve accessions with a mean score ≤1 were selected for morpho-agronomic characterization. ‘Sugar Baby’ and ‘Charleston Gray’ were used as controls. Field research was conducted over two production cycles in a randomized block design with three replications and five plants per plot. For the characterization 13 quantitative agronomic traits were used. The dissimilarity measures were obtained by the sum of the matrices of standardized mean Euclidean distance. Coefficients of variation ranged from 5.33% (number of days until 50% of plants with at least one female flower) and 17.20% (mass of characterized fruit). In the second cycle, a reduction in days was observed for the flowering. For soluble solids content, the accession BGH-UNIVASF 40 was statistically equal to the commercial cultivars in the second cycle. Accessions were grouped similarly using two grouping methods, Tocher and the farthest neighbor method. The most promising accessions were BGH-UNIVASF 40, 169, 177 and 210 for use in future hybridizations. BGH-UNIVASF 76, 128 and 185 (Citrullus lanatus var. citroides) can be used as resistant Fusarium wilt rootstocks.

Abstract Background: Weeds reduce water use efficiency in crops due to water used by the weed and to the reduction in crop yield. In addition to the usual presence of weeds in the interrow of different crops, the management of these plants has moved away from the idea of total control. Thus, the amount of water lost through the evapotranspiration of weeds (ETW) must be understood. Objective: Determine the water use and crop coefficient (Kc) of the weed species Commelina diffusa, Cyperus rotundus, and Cynodon dactylon using drainage lysimeters associate with the Normalized Difference Vegetation Index (NDVI). Methods: The experiment was carried out at the Lysimetric Station of the Federal University of Viçosa, in Viçosa-MG, in a randomized block design, with four treatments and four replicates. Reference evapotranspiration (ETo), necessary to calculate Kc, was obtained in situ through lysimeters cultivated with Paspalum notatum. Results: The highest Kc values were found in the final third of the experimental cycle, equal to 1.32, 0.93, and 0.90 for C. diffusa, C. rotundus, and C. dactylon, respectively. The NDVI showed a good correlation with Kc and biomass, with R2 ranging from 30.9 to 54.6% and from 46.1 to 63.1%, respectively. Accumulated ETW values ranged from 336 to 473 mm, with C. diffusa showing the highest water consumption, followed by C. rotundus and C. dactylon. Conclusions: C. diffusa has higher Kc and water consumption than C. rotundus and C. dactylon. NDVI can be used in the estimation of the Kc and biomass of weeds.

RESUMO Em regiões onde a área irrigada é crescente e a disponibilidade hídrica é reduzida, como o Oeste do Estado da Bahia, Brasil, o emprego de técnicas que contribuam para melhorar a eficiência de uso de água é primordial. Uma das formas de melhor adequação da irrigação é através da melhoria do cálculo da evapotranspiração atual (ETa), que entre outros fatores, é influenciada pelo secamento do solo, sendo importante entender essa relação, que geralmente é contabilizada nos modelos de manejo de irrigação por meio do coeficiente de estresse hídrico (Ks). Este estudo objetivou estimar o coeficiente de estresse hídrico (Ks) por meio de informações obtidas via sensoriamento remoto, combinadas com informações de campo. Para isto, realizou-se um estudo no município de São Desidério, área localizada no Oeste da Bahia, utilizando imagens do satélite Landsat-8. O Ks foi calculado pela relação entre a evapotranspiração da cultura e a ETa, calculada pelo Simple Algorithm for Evapotranspiration Retrieving (SAFER). O Ks estimado por sensoriamento remoto apresentou para os estádios em desenvolvimento e médio, erros médios da ordem de 5,50%. No estádio final de desenvolvimento do milho os erros obtidos foram de 23,2%.

ABSTRACT In regions where the irrigated area is increasing and water availability is reduced, such as the West of the Bahia state, Brazil, the use of techniques that contribute to improving water use efficiency is paramount. One of the ways to improve irrigation is by improving the calculation of actual evapotranspiration (ETa), which among other factors is influenced by soil drying, so it is important to understand this relationship, which is usually accounted for in irrigation management models through the water stress coefficient (Ks). This study aimed to estimate the water stress coefficient (Ks) through information obtained via remote sensing, combined with field data. For this, a study was carried out in the municipality of São Desidério, an area located in western Bahia, using images of the Landsat-8 satellite. Ks was calculated by the relationship between crop evapotranspiration and ETa, calculated by the Simple Algorithm for Evapotranspiration Retrieving (SAFER). The Ks estimated by remote sensing showed, for the development and medium stages, average errors on the order of 5.50%. In the final stage of maize development, the errors obtained were of 23.2%.

Fridericia speciosa (Bignoniaceae) is a liana that occurs in humid to dry vegetation in eastern and southeastern Brazil. Species belonging to the genus Fridericia are employed as medicinal plants. This study evaluates the antipromastigote and cytotoxic activities of the crude extract, fractions, and compounds isolated from F. speciosa, and an HPLC (High-Performance Liquid Chromatography) analytical method was used to quantify the bioactive flavonoids. The flavonoids alpinetin (1), luteolin (2), diosmetin (3), and apigenin (4) were isolated from the active EtOAc-soluble fraction (EAF) of the crude ethanol extract (LCE) obtained from F. speciosa leaves. Both LCE and EAF were active against the normal human lung fibroblast cell line GM07492A (IC50 of 460.7 µg mL-1 and 381.4 µg mL-1, respectively). Only EAF showed activity against Leishmania amazonensis (80.4% at 50 µg mL-1). Compounds 1 and 2 were quantified by HPLC-DAD in both LCE (1: 6.21%; 2: 1.11%) and EAF (1: 45.32%; 2: 2.00%). At 100 µM, compounds1-4 inhibited L. amazonensis flagellar motility by 40.2%, 26.8%, 1.0%, and 24.8%, respectively, while their toxicities (IC50) to the normal cell were > 1000, 353.0, 766.2, and >1000 µg mL-1, respectively. Therefore, F. speciosa leaves are a prolific source of bioactive flavonoids.

ABSTRACT Objective: Assess adherence to school food offered by the School Food Program (Programa Nacional de Alimentação Escolar - PNAE) and the associated factors among Brazilian adolescents. Methods: Cross-sectional study with data from the Study of Cardiovascular Risks in Adolescents conducted in 2013-2014, with 58,707 adolescents aged 12 to 17 years-old who attended public schools. Logistic regression models were stratified by sex and the significance level of 5% was adopted for all analyses. Results: There was low adherence to school meals (17.2%). The chance of regular consumption of school meals was higher among male adolescents belonging to the medium (p<0.05) and the low (p<0.05) socioeconomic score categories. For females, the chance of regular consumption of food offered at school was higher among black-skinned, brown-skinned, indigenous-skinned or yellow-skinned adolescents (p<0.05), aged 16 and 17 (p<0.05), who worked (p<0.001) and belonged to the medium (p<0.05) and low (p<0.05) socioeconomic score categories. The regular purchase of food in school cafeterias reduced the chance of regular consumption of school meals for males (p<0.001) and females (p<0.001). Conclusions: Adherence to the food offered by the PNAE is far from ideal, and it is important to create public policies that encourage the consumption of school meals and improve adherence. In addition, the strengthening and drafting of regulations aimed at the sale of food in the interior and surrounding schools' areas is necessary.

RESUMEN Objetivo: Evaluar la adherencia a la comida escolar ofrecida por el Programa Nacional de Alimentación Escolar y los factores asociados entre los adolescentes brasileños. Métodos: Estudio transversal con datos del Estudio de Riesgos Cardiovasculares en Adolescentes realizado en 2013-2014, con 58.707 adolescentes de 12 a 17 años que asistieron a escuelas públicas. Los modelos de regresión logística se realizaron estratificados por sexo, y se aplicó el nivel de significancia del 5% para todos los análisis. Resultados: Hubo baja adherencia a las comidas escolares (17,2%). La posibilidad de consumo regular de comidas escolares fue mayor entre los adolescentes varones pertenecientes a las categorías de puntaje socioeconómico medio (p<0,05) y bajo (p<0,05). Para las mujeres, la probabilidad de consumo regular de alimentos ofrecidos en la escuela fue mayor entre las adolescentes de piel negra, marrón, indígena o amarilla (p<0,05), de 16 y 17 años (p<0,05), quién trabaja (p<0,001) y pertenece a las categorías de puntaje socioeconómico medio (p<0,05) y bajo (p<0,05). La compra regular de alimentos en las cafeterías escolares redujo la posibilidad de consumo regular de comidas escolares para hombres (p<0,001) y mujeres (p<0,001). Conclusiones: La adhesión a los alimentos ofrecidos por el PNAE está lejos de ser ideal, y es importante crear políticas públicas que fomenten el consumo de comidas escolares, mejoren su adherencia, además de ayudar en el fortalecimiento y la redacción de regulaciones dirigidas a la venta de alimentos en el interior y las áreas de las escuelas circundantes.