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In the present work, a simple and high-throughput analytical procedure based on ultrasound-assisted extraction with diluted acid was proposed for the determination of Ca, Mg, K, P, S, Fe, Cu and Mn in guarana samples using inductively coupled plasma optical emission spectrometry. Two multivariate approaches were employed for optimization of the extraction procedure: mixture and Doehlert designs. The best experimental conditions were established by application of a multi-response function (overall desirability). An extractor medium composed of diluted nitric acid was selected for analytes extraction. Optimized conditions for ultrasound-assisted extraction followed the temperature of 60 °C, sonication time of 10 min and power of 100% applied to the ultrasonic bath. After the analytical validation step, the proposed procedure was successfully employed for determination of essential elements in thirty-three guarana samples from the state of Bahia, Brazil. Mass fractions higher than 0.42% (m m-1) were found for potassium in all analyzed samples. For the other macro-elements, the mass fraction ranged from 514 mg kg-1 (magnesium) to 0.19% m m-1 (calcium). The mass fraction of micro-elements ranged from 5.1 to 91.3 mg kg-1 for cooper and iron, respectively.

A cacauicultura é uma importante atividade de geração de emprego, renda e desenvolvimento de milhares de agricultores no Brasil, notadamente no Estado da Bahia que é um dos maiores produtores do país. Assim, a avaliação da lavoura de cacau poderia contemplar diferentes dimensões e gerar informações que contribuam para o desenvolvimento das áreas produtoras. Nesse trabalho, objetivou-se analisar o desempenho da lavoura cacaueira a partir de um sistema de indicadores, e através de um índice correlacionar os resultados. Os dados foram provenientes do Censo Agropecuário e da Pesquisa Agrícola Municipal, do Instituto Brasileiro de Geografia e Estatística. A pesquisa é básica com metodologia quantitativa, utilizando técnicas estatísticas de agrupamento e análise de variância. A análise demonstra que o índice criado é capaz de estratificar os municípios em três níveis, aponta a existência de correlação positiva entre associação de produtores e a produção, bem como que o rendimento médio da produção e a assistência técnica são deficientes. Infere-se, que se faz necessário fortalecer a assistência técnica, identificar os fatores intervenientes do baixo rendimento da lavoura, assim como, compreender os aspectos da relação positiva entre associativismo e produção, com vistas ao incremento do desenvolvimento das áreas produtoras.

Made available in DSpace on 2021-06-25T15:05:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-06 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The aim of this study was to evaluate the variability, partition, and correlation of Fe, Mn, and Zn in the leaves and fruit components (pod husk, pulp, tegument, and cotyledons) of cacao trees. These contents were also correlated with chemical attributes of the soils in regions classified as humid (H), humid to sub-humid (SH), and sub-humid to dry (SD) in the South Bahia, Brazil. Soils samples were collected, along with leaves and fruits from the PH16 clone of the cacao tree, for analysis of Fe, Mn, and Zn. Descriptive statistics and Pearson's correlation were applied, as well as Shapiro Wilk's normality test and Tukey's test for comparison of the climate regions. The accumulation order for Fe and Zn in the fruit components was tegument > pod husk > leaf > cotyledons; and for Mn the order was pod husk > leaf > tegument > cotyledons. The increase in hydric restriction, from the most humid region to the driest, causes natural bioconcentration of Fe, Mn, and Zn in the fruit components used to produce food (cotyledons and pulp). The Mn contents in the leaf can be used as indicators of its accumulation in the cotyledon and cacao pulp. Univ Estadual Santa Cruz, Dept Agr & Environm Sci, Ilheus, BA, Brazil Sao Paulo State Univ, Dept Soil & Fertilizer, Jaboticabal, SP, Brazil Univ Estadual Santa Cruz, Dept Exact & Technol Sci, Ilheus, BA, Brazil Sao Paulo State Univ, Dept Soil & Fertilizer, Jaboticabal, SP, Brazil CAPES: 001

O gerenciamento dos residuos da etapa agricola producao de alimentos, e uma questao prioritaria e abrange estrategias visando minimizar os impactos ambientais. O emprego das larvas da mosca Hermetia illucens como detritivoros e uma alternativa promissora, pois ao longo do seu desenvolvimento acumulam oleo e proteina, cujas aplicacoes sao diversas. No presente trabalho, larvas da H. illucens foram alimentadas com diferentes formulacoes de uma mistura de casca de cacau, soro de leite e semente de maracuja. As larvas foram caracterizadas quanto ao teor de proteina e a qualidade do oleo produzidos. Foi possivel obter uma biomassa larval com ate 36% de oleo e 46% de proteina. O teor de proteina a torna promissora como racao na pecuaria. O perfil de acidos graxos do oleo mostrou uma alta concentracao de C12:0 (47%), seguida por C18:2, C16:0 e C18:1, o que permite caracteriza-lo como oleo laurico, com aplicacoes diversas na industria oleoquimica.

The present study evaluated the influence of land use and occupation on water quality indices (WQI); the WQI developed by the National Sanitation Foundation (NSF), the WQI adapted by the Environmental Company of the Sao Paulo State (CETESB), WQI proposed by Bascaron and the Canadian Council of Ministers of the Environment (CCME) WQI, obtained for watersheds located in the Eastern Water Planning and Management Region (BA). The study also analyzed the divergences and similarities of these WQI methods. Water quality data were obtained from the Monitoring Program (Monitora) of Environment and Water Resources Institute of Bahia (INEMA), covering the period from 2008 to 2015, at thirteen (13) sampling sites, with quarterly collections, as well as land use and occupation data. The influence of land use and occupation on water quality indices was assessed by principal component analysis (PCA). The PCA showed that urban and agricultural/pasture areas were influencing factors on water quality variables, such as total phosphorus, biochemical oxygen demand, total nitrogen, turbidity total residues and consequently lower WQI values in the Cachoeira watershed. Among the tested methods to evaluate the water quality of watersheds in the study area, the most similar were the NSF WQI, CETESB WQI, and Objective Bascaron WQI.

In this work, a simple, easy, and fast ultrasound-assisted extraction procedure for the determination of Cu, Fe, Mn, and Zn in plant samples was developed. Sample preparation conditions were optimized in a multivariate manner using mixture design and Box-Behnken. The extraction conditions adequate to obtain the maximum response were 90% power, 10 minutes, 40 °C temperature, and using an extraction solution composed of HNO3 and HCl at a concentration of 0.5 and 1.1 mol L-1, respectively, for a volume of 10 mL and 250 mg of samples. Accuracy was verified from the analysis of a certified reference material (Apple leaves, NIST 1515) yielding recoveries between 89 and 98% for the procedure. Precision was evaluated in a repeatability study (n = 10), yielding RSDs less than 6.7%, and the limits of quantification (mg kg-1) were 0.95, 2.42, 1.31, and 1.18 for Cu, Fe, Mn, and Zn, respectively. The concentrations determined in the stem and leaf of the mangrove species varied according to the collection point and the tissue, being consistent with other studies. The proposed procedure was efficient and reliable for elemental determination in plant samples, with the advantages of low cost and reagent consumption besides short analysis time as a valid alternative to the conventional sample preparation procedure.

Made available in DSpace on 2020-12-12T01:35:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-07 Fish are important sources of protein, making them very significant in the human diet. Although the consumption of this food is beneficial for health, it is essential that the product does not contain inorganic components above the limits recommended by the current legislation. Therefore, a method for determination of elements in fish (Mugil cephalus) samples was optimized. A simplex centroid mixture design with restriction was applied for optimization of the acid digestion of samples in an open system under reflux in order to evaluate the best ratio between the reagents HNO3, H2O2 and H2O. The results indicated that more intense analyte signals were obtained when a mixture containing 3.6 mL of HNO3 (65% v/v), 0.4 mL of H2O2 (30% v/v) and 6.0 mL of H2O was used. The accuracy of the method was assessed with a CRM of oyster tissue (NIST 1566b). The method presented relative standard deviations (RSDs) of 3.54%; 3.82%; 4.81% and 3.50% for Zn, Fe, Cu and S, respectively. The detection limits were 0.002 mg kg-1 for Cu and Zn and 0.02 mg kg-1 for Fe and S. The proposed method was applied for the determination of Zn, Fe, Cu and S in fish samples. A Kohonen Self-Organizing Map (KSOM) with K-means implementation was applied to better delimit the boundary between groups and the spatial and temporal influence on how concentrations of the chemical elements were perceived. To verify the separation, the Davies-Bouldin and Silhouette indices were used, obtaining 0.5374 and 0.8541, respectively, indicating satisfactory separation. Departamento de Ciências Exatas e Tecnológicas Universidade Estadual de Santa Cruz Campus Soane Nazaré de Andrade, Km 16 BR-415 Instituto de Química Universidade Federal da Bahia Campus Universitário de Ondina Departamento de Química e Exatas Universidade Estadual Do Sudoeste da Bahia Campus Universitário de Jequié-BA Avenida José Moreira Sobrinho, 677-Jequiezinho Institute of Chemistry São Paulo State University (UNESP) Institute of Chemistry São Paulo State University (UNESP)

Bioconversion by Hermetia illucens larvae is a novel technology for organic waste treatment and valorization. However, since the possible uses of products from this process are in agriculture and livestock, the bioconversion must guarantee the mineral quality of both the Hermetia illucens larvae frass and larval biomass. Therefore, this study aimed to assess the mineral content changes for both the larval biomass and larvae frass of Hermetia illucens after the manure bioconversion to determine their suitability as animal feed and organic fertilizer, respectively. Hermetia illucens larvae were put into a plastic box containing fresh cattle manure, and the control treatment with the same conditions without larvae was established. After the first pre-pupae were detected, frass and larvae were collected, and their mineral content was analyzed. At the end of the experiment, the larvae showed increases in some micro and macronutrients, especially calcium and manganese, increasing up to 2.6 and 22.6 times the initial concentration, respectively. The toxic elements concentration was increased in larval biomass, but these levels met the international legislation for animal feed. As a result, the mineral content in larval biomass revealed that Hermetia illucens could be potentially used as animal feed, which could be comparable with fish meal, and is probably better than soybean meal. However, the larvae frass could only be used as organic fertilizer in a Canadian context, with further treatment for decreasing the chromium content being necessary.

Este trabalho possui o objetivo de analisar a viabilidade econômica e ambiental da instalação de unidade de microgeração de energia solar fotovoltaica e de aproveitamento de água de chuva em três escolas da rede pública de Ilhéus. O método adotado contempla a análise do enquadramento legal vigente no Brasil, o levantamento de dados de consumo de água e energia elétrica, o cálculo de irradiaçãoolar e de precipitação pluviométrica incidente na área e, o dimensionamento dos sistemas de microgeração de energia elétrica solar e de aproveitamento de água de chuva em cada unidade escolar estudada. Os resultados encontrados demonstram viabilidade econômica e ambiental, uma vez que a implantação desses sistemas promove economia mensal de aproximadamente 96% no consumo de energia elétrica e 40% no consumo mensal de água potável nas unidades escolares estudadas.

A microwave-assisted digestion procedure using diluted HNO3 and H2O2 was developed for multi-element determination in guarana samples by ICP OES. Optimization step was performed employing a mixture design with pseudocomponents using HNO3, H2O2 and H2O. The analytical signal of each element, residual acidity and residual carbon content were optimized simultaneously using the desirability function. The best condition for digestion of a 250 mg sample mass resulted from a mixture constituted by 1.0 mL of HNO3, 3.0 mL of H2O2 and 6.0 mL of H2O. This condition allowed final digests with residual acidity and residual carbon content of 0.4 mol L−1 and 6.5%, respectively. The method was validated and applied for the determination of K, Ca, Mg, S, P, Cu, Fe, Mn and Zn in 72 guarana seed samples from Bahia state. This work presents unpublished results about the mineral composition of guarana seed samples produced in Bahia state, Brazil.

Este estudo teve como principal objetivo utilizar Laguncularia racemosacomo bioindicador da presença de metais no manguezal do estuário do rioBuranhém, na cidade de Porto Seguro, extremo sul da Bahia. Para tanto,coletaram-se folhas verdes e amarelas dessa planta em quatro pontos doestuário. Essas amostras passaram por digestão ácida (método 3050-B daUnited States Environmental Protection Agency — USEPA) para posteriorquantificação de metais via espectrometria de emissão ótica com plasmaindutivamente acoplado (ICP OES). Os valores mínimos e máximos para asconcentrações de metais encontradas foram, respectivamente, em mg.kg-1:Cr: 0,29 a 2,90; Mn: 7,92 a 72,13; Fe: 74,07 a 392,67; Ni: 0,25 a 1,24; Cu: 0,18a 1,19; Zn: 6,62 a 16,93; Sr: 47,09 a 167,28; Cd: 0,06 a 36,42; Ba: 3,20 a17,24; e Pb: 2,59 a 145,90. Os resultados obtidos indicam que a Lagunculariaracemosa constitui um bioindicador de metais de potencial relevância noque diz respeito à qualidade de ecossistemas estuarinos. This study had as main objective to useLaguncularia racemosaas abioindicator of the presence of metals in the mangrove of the Buranhémriver’s estuary, in the city of Porto Seguro, southern Bahia, in May 2017. Forthis purpose, green and yellow leaves from this plant were collected at fourpoints in the estuary. These samples underwent acid digestion (USEPA3050‑Bmethod) for further quantification of metals by ICP OES. The minimum andmaximum values for the concentration of metals found were, respectively(mg kg‑1) Cr:0,29 -2,90; Mn: 7,92‑ 72,13; Fe:74,07 ‑392,67; Ni:0,25 ‑1,24;Cu: 0,18 ‑1,19; Zn: 6,62‑ 16,93; Sr: 47,09‑ 167,28; Cd: 0,06 ‑36,42;Ba:3,20 ‑17,24; and Pb: 2,59‑ 145,90. The results indicate thatLagunculariaracemosa is a bioindicator of metals with a relevant potential regarding thequality of mangrove ecosystems.

In this work, a method was developed for the determination of Na, K, Ca, Mg, P, S, Fe, Zn, Mn, and Cu by ICP OES and caffeine and epicatechin by HPLC-DAD in industrialized guarana-based beverages. The acid digestion in microwave oven was optimized by constrained mixture design. The optimum volumes found for the reagents were 2.60 mL (HNO3), 1.80 mL (H2O2), and 0.60 mL (HCl) for a final volume of 10 mL, resulting in a final digestate with residual acidity of 0.8 mol L−1 and 9% for residual carbon content. The detection limits found for the studied elements were between 0.0010 and 0.050 mg L−1. Precision (%RSD) was always below 6%. Accuracy was assessed by analyzing a certified reference material and addition and recovery tests. PCA and HCA were applied to caffeine, epicatechin and elemental concentrations aiming to evidence latent information.

An infection of the fungus Moniliophthora perniciosa in cocoa trees reduces productivity of the plant. In this study, the concentrations of mineral nutrients in healthy leaves and in leaves of vegetative broom of the cocoa plant were determined, and the relationship between the disease and the nutritional composition of the leaves was assessed. The samples were analyzed using the wet digestion method and the concentrations were determined by inductively coupled plasma optical emission spectrometry and the Kjeldahl method. Results indicate that leaves of vegetative broom have lower concentrations of Ca, Mg, S, Fe, Mn, and Ni than healthy leaves. Concentrations of P and Cu were lower in healthy leaves and higher in leaves of vegetative broom. In contrast, concentrations of K, N, and Zn were the same for both types of leaves. In short, plant-fungal interaction was reflected in the nutritional composition of the leaves, demonstrated by the differences in nutrient concentrations between healthy and infected leaf tissue.

A simple analytical procedure is proposed for the direct analysis of guarana-based beverages in order to determine nutrient elements by inductively coupled plasma optical emission spectrometry (ICP OES). A Box-Behnken design, combined with Derringer’s desirability function, was applied to the simultaneous optimization of the ICP OES radiofrequency (RF), sample volume and nitric acid concentration. Using this approach, optimal conditions were established as RF power of 1.40 kW, and 5.0 mL of sample diluted twice with 0.5 mol L-1 HNO3. The optimized procedure allowed the determination of Cu, Fe, Mn, Zn, K, Ca, S, P and Mg with limits of quantification of 10.0, 2.0, 0.6, 6.0, 66.0, 65.0, 235, 40.0 and 20.0 μg L-1, respectively. Accuracy of the method was evaluated through analysis of water standard reference material (SRM NIST 1643f) and by additionrecovery experiments, in which satisfactory recoveries were obtained. The procedure was applied for the analysis of guarana-based soft and energy drinks. The concentration ranges (mg L-1) were: 0.36‑43.3 (Ca), 4.04-192 (K), 0.36-44.8 (Mg), 10.1-1,073 (S), 0.04-92.4 (P), < 0.010-0.0174 (Cu), < 0.002-0.294 (Fe), < 0.006-0.06 (Zn) and < 0.0006-0.168 (Mn).

Ammonium ion of digested samples of food, soil, fertilizer and water was determined based on the reaction of the ammonium ion with formaldehyde, and then titrated with sodium hydroxide solution. The optimization of variables such as the amount of formaldehyde and EDTA concentration carried out through univariate analysis. Under optimized conditions, the method allowed ammonium determination with the achieved detection limit of 1.83mgL-1, a quantification limit of 6.11mgL-1 and precision of 6.0-0.5% for ammonium solutions of 0.400-3.773mgL-1 concentration, respectively. The procedure was validated using the Kjeldahl method. The method was successfully applied to determinate ammonium in samples of water, soil, fertilizer and oat. The proposed procedure resulted in a simple, fast and cost effective method to the determination of ammonium in routine analysis. O íon amônio de amostras digeridas de alimentos, solo, fertilizante e água foi determinado baseado na reação do íon amônio com formaldeído e, em seguida, titulado com solução de hidróxido de sódio. A otimização de variáveis como quantidade de formaldeído e concentração de EDTA foi realizada por meio de análise univariada. Em condições otimizadas, o método permitiu a determinação de amônio com o limite de detecção alcançado de 1,83 mg L-1, um limite de quantificação de 6,11 mg L-1 e precisão de 6,0 - 0,5% para soluções de amônio na concentração de 0,400 - 3,773 mg L-1, respectivamente. O procedimento foi validado pelo método Kjeldahl. O método foi aplicado com sucesso para determinar amônio em amostras de água, solo, fertilizante e aveia. O procedimento proposto resultou em um método simples, rápido e de baixo custo para a determinação de amônio em análises de rotina.

Macro- and microelement determination in chocolate bars by microwave-induced plasma optical emission spectrometry (MIP OES) was evaluated after microwave-assisted sample digestion. Optimization of the sample digestion was carried out, and the recommended conditions were obtained at a temperature of 190 °C, with a digestion time of 40 min and in a mixture constituted by 2.3 mL of nitric acid, 1.0 mL of hydrogen peroxide and 4.7 mL of water. The method was applied in the analysis of chocolate bars, and the concentration ranges of the elements determined were (in mg kg−1): Ca (653–3096); Cr (

Plant litter has several functions in a forest ecosystem. Studies about plant litter are of great importance to better understand and conserve ecological environments. The objective of this study was to investigate the concentration of metals (Fe, Co, Ca, Cu, Ni, Mg, Mn and Zn) in Caatinga plant litter in the southwest region of Bahia. Plant litter was collected in summer (January/2017) and winter (August/2017). Concentrations were determined by flame atomic absorption spectrometry (FAAS). The results were submitted to multivariate analysis, principal component analysis (PCA), and hierarchical cluster analysis (HCA). The average amount of plant litter found in January and August was 1190 and 1329 kg ha-1, respectively. The twigs fraction provided the largest amount of biomass to the plant litter since this deposition occurred in greater quantity in August, a period of drought. Metal concentrations (g kg-1) in the analyzed samples ranged from 1.39-257 (Fe), < limit of quantification (LOQ)-0.269 (Co), 0.0036-0.61 (Cu), 1.39-8.76 (Ca), 0.0022-0.56 (Ni), 0.137-1.52 (Mg), 0.033-1.91 (Mn) and 0.0022-0.8 (Zn). The multivariate analysis showed that the composition of plant litter is altered seasonally.

In the present study, the physicochemical properties and mineral composition of commercially-frozen soursop pulps from the southern region of the state of Bahia, Brazil, were evaluated. The physicochemical parameters such as soluble solids (°Brix), acidity and pH were determined according to reference methodologies. For mineral composition evaluation, samples were digested in a closed microwave system and the elements K, P, S, Ca, Mg, Fe, Cu, Zn, and Mn were quantified through inductively coupled plasma optical emission spectrometry (ICP OES). Soluble solids content ranged from 4.77 to 15.37 °Brix among the different brands of analyzed frozen pulps. Titratable acidity (equivalent to citric acid) and pH ranged from 0.49 to 1.00 and 3.61 to 4.57, respectively. Some samples presented irregularities in regard to quality pattern established in the Brazilian legislation. The following range of concentration, in μg g-1, were found for essential elements: K (544-1761), P (44.3-139), S (71.8-174), Ca (24.3-77.0), Mg (47.2-132), Fe (1.40-4.05), Mn (0.32-1.22), Cu (0.30-0.88) and Zn (0.36-0.84). The use of principal component analysis (PCA) enabled a more in-depth data analysis, performing correlations between different variables and frozen pulp brands.

This study is the first to propose the simultaneous quantification of 10 elements in fruits of Casearia fasciculata by inductively coupled plasma optical emission spectrometry (ICP OES). A method of digestion using dilute nitric acid was optimized by mixture design for extraction of elements in the seed, peel, and pulp of Casearia fasciculata cultivated in the Bahia State, Northeastern Brazil. Four different approaches were used to evaluate the digestion procedure ((i) desirability; (ii) multiple response; (iii) residual carbon content and (iv) residual acidity). The accuracy of the method of digestion was applied for the extraction of the studied elements in two certified reference materials (RM-Agro E1001a Brachiaria brizantha and NIST 1515 apple leaves). The limits of quantification of the method (µg g−1) were: Cr, 0.42; Cu, 0.69; Fe, 1.5; Mn, 0.14; Zn, 1.8; Ca, 29.0; K, 3.5; Mg, 1.9; P, 6.4; and S, 17. Two multivariate tools, principal component analysis (PCA) and hierarchical cluster analysis (HCA), were efficient in the formation of groups, corresponding to the fruit parts. Thus, the peel and seed of Casearia fasciculata present potential to be used as mineral supplements in human nutrition.

Changes to land use generate imbalances in the natural dynamics of aquatic ecosystems. These changes can vary according to the specific characteristics of each environment and due to seasonal factors, reinforcing the importance of studies in this area in different regions of the globe. Thus, the aim of this study was to analyze the effects of land use change on the rivers and streams of the Cachoeira River Basin in the Northeast of Brazil. Samples were collected bi-monthly at 16 points along the basin over 1 year and analyzed for physical and chemical parameters (temperature, pH, conductivity, and percentage saturation of dissolved oxygen), inorganic nutrients (NO3−, NO2−, NH4+/NH3, PO43−, SiO4) and dissolved major ions (Ca2+, K+, Mg2+, Na+, HCO3−). The highest concentrations of NO3−, NO2−, NH4+/NH3, and PO43− occurred at the points with the highest percentage of urban areas and population density. The major ions Ca2+, K+, Mg2+, Na+, and HCO3− were positively correlated with the percentage of pasture coverage; however, the high concentrations of these ions and the strong correlation between them revealed that other factors besides land use, such as soil cover, geological formation, and water deficit, may be jointly contributing to increases in their concentrations. Thus, the results show that urbanization represents the type of land use with the greatest negative effect on water quality since it alters the concentrations of inorganic nutrients dissolved in the Cachoeira River Basin.

Isotonic repositories are specially designed to promote rehydration during or after physical exercise. These beverages are processed for commercialization from synthetic flavorings and dyes with sensorial characteristics similar to those of fruits, in order to attenuate their natural acidity. The aim of the present study was to develop two formulations of isotonic drinks without synthetic dyes and with functional attributes based on concentrated hydroethanolic extracts of peel and pulp of Myrciaria jaboticaba. Determination of chemical (sodium, potassium and calcium, total phenolics, total anthocyanins, total flavonoids, total condensed tannins), physical (objective color analysis), and physical-chemical characteristics (pH, acidity, total soluble solids), as well as sensory evaluation through preference testing was carried out. In addition, the drinks presented dark red coloration, according to the chromaticity diagram. The sensory evaluation results revealed that the beverage formulated with 12% pulp extract stood out as the preferred beverage among the judges.

Organic dyes originating from liquid effluents from the textile industries are harmful to the environment. They are toxic and reduce the penetration of light into aquatic environments. In this study, a biosorbent was produced from the exuviae of Hermetia illucens (Linnaeus) larvae and used to remove organic anionic dyes from an aqueous medium. The solids were characterized in terms of thermal stability, chemical structure, morphology, and porosity using thermogravimetric (TGA), differential thermal analysis (DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N2 adsorption-desorption. There were studied the effects of pH and dosage of the adsorbent on the adsorption of the bromophenol blue dye, used as a model molecule. The adsorption kinetics was studied with Lagergren’s pseudo-first-order rate model. The maximum adsorbed amount was 571 mg g−1 according to Langmuir’s model. The adsorption process was evaluated as exothermic and spontaneous and was classified as physical adsorption. The prepared biosorbent was tested in five consecutive adsorption cycles achieving 99% dye removal at each stage. This demonstrated the maintenance of adsorption efficiency and desorption capacity. These results suggest that prepared biosorbent have potential applications in the treatment of effluents from textile industries.

Eutrophication is a natural process within the ecological succession of aquatic ecosystems that results from nutrient inputs to water bodies, especially limiting elements such as phosphorus and nitrogen. However, the anthropogenic activities in river basin influence areas accelerate the eutrophication process of water bodies. Eutrophication is a global problem and considered one of the most relevant reasons of aquatic environments' degradation. In this context, watercourses that make up the Eastern Water Planning and Management Region (RPGA) receive high pollutant contributions due to release of wastewater and agriculture diffuse sources from cities located in influence area. The present study aims to evaluate the land use effect in trophic state of the water bodies in Eastern RPGA basins. The Carlson Trophic State Index in 1977, adjusted by Lamparelli 2004, was used to determine the eutrophication degree of the three river basins (Almada, Cachoeira, and Una) located in the Eastern RPGA. The nutrient and chlorophyll a data were obtained from the Monitoring Program (Monitora) of Environment and Water Resources Institute of Bahia (INEMA), covering the period from 2008 to 2015, at thirteen (13) sampling sites, with quarterly collections. The results showed that, among three basins analyzed, Cachoeira River basin presented the worst values for trophic state index (TSI) due to the high level of anthropization, while best results were found in Una basin. It was verified that land use exerted a significant influence on the water quality of bodies of water evaluated.

A vulnerabilidade denotada pela pandemia causada pelo SARS-CoV-2, deflagrou na população mundial preocupação em estabelecer medidas de contenção emergencial. Embora, até o momento, poucos estudos estabeleçam o esgoto sanitário como via de contaminação do SARS-CoV-2, no Brasil a instabilidade de destinação dos efluentes, estabeleceu um alerta acerca da incapacidade dos sistemas públicos de proverem a implementação de captação e tratamento adequado dos efluentes domésticos. Este artigo apresenta evidencias em base de dados cientificas eletrônicas nacionais e internacionais que corroboram uma pluralidade de tecnologias emergentes de desinfecção de águas residuais aplicáveis, eficientes e seguras para desinfecção dos efluentes em suas etapas de tratamento, prevenindo o despejo de dejetos potencialmente contaminados no meio ambiente. Colaborando com a mitigação de doenças e com a necessária remodelação dos processos de desinfecção de efluentes, considerando os recursos e a realidade brasileira.

The objective of this study was to propose derivatization assisted by microwave radiation using hexamethyldisilazane as a low cost silanizing agent, in order to determine phenolic compounds in wines. Thus, an analytical method was developed and validated for the quantification of gallic acid, caffeic acid, resveratrol, (−) – epicatechin and (+) -catechin in wine samples by gas chromatography. The Box-Behnken design was used to optimize the experimental conditions of the derivatization reaction and extraction of the analytes from the matrix. The validated method presented limits of quantification in the range of 0.413–1.023 mg L−1 and standard deviation (%RSD) lower than 4.81%. Accuracy was verified by comparing the proposed method with a method that uses BSTFA as silanizing agent, with no significant differences between the determined concentration values. The proposed method was used to quantify the analytes in nine wine samples, with reduced analyte derivatization time, low derivative reagent cost and appropriate values of analytical figures of merit.

To assess environmental contamination, studies have been increasingly carried out using biomarkers to diagnose the effects of toxic metal exposure, such as metallothionein (MT). In this context, the aims of the present study were to determine Cd, Cu, Ni and Pb concentrations, by ICP-MS, in liver samples from Mugil cephalus from the municipality of Ilheus, located in North-Southeastern Brazil, in the state of Bahia, which has been increasingly suffering from anthropogenic pressure, and to quantify total MT in liver and gills. Among essential metals, copper (199.2 μg g−1) presented concentrations approximately 7 times higher than allowed by the World Health Organization (30 μg g−1). Liver samples showed higher concentrations than gills. Metallothionein concentrations indicate differential contamination along the study area. The first sampling showed higher induction of MT synthesis overall. Differences between liver and gill MT concentration trends were relatively minor, which may indicate the adequacy of analyzing gills in an environmental monitoring context.

We identified and characterized two chitinases, named MpCHIT1 and MpCHIT2, from the fungus Moniliophthora perniciosa - the etiologic agent of witches' broom disease in cacao tree (Theobroma cacao L.) - during its development, mainly in the mycelia phases preceding the basidioma formation. The expression of MpCHIT1 and MpCHIT2, together with MpCHS and MpATG8 (chitin synthase and autophagy genes, respectively), was analyzed during the M. perniciosa growth and development on bran-based solid medium as well as in liquid medium containing H2O2 or rapamycin (oxidative and nutritional related-autophagy stress agents, respectively). In order to link the expression of chitin metabolism-related genes to nutritional composition influencing fungus development, we also quantified total and reduced sugars, as well as macro- and micronutrients in the bran-based solid medium. The expression analysis showed that the MpCHS expression increased through mycelial development and then decreased in the primordium and basidioma phases, while the expression of MpCHIT1 and MpCHIT2 was higher in basidioma and primordium phases, respectively. Moreover, the expression pattern of MpCHIT1 and MpCHIT2 is distinct, the second correlated with the MpATG8 expression pattern and possibly with autophagy process, while the first may be related to the basidioma formation. The quantification of total and reduced sugars, as well as macro- and micronutrients supported the idea that the cell wall restructuration due to MpCHS, MpCHIT1 and MpCHIT2 is related to stress and fungal nutrient reallocation, allowing the formation and development of the basidioma. Experiments involving M. perniciosa growth on liquid medium containing H2O2 or rapamycin showed that MpCHIT1 and MpCHIT2 were over-expressed in response to oxidative but also to nutritional related-autophagy stresses. Interestingly, the expression level of MpCHS, MpCHIT1 and MpCHIT2 in presence of rapamycin is similar to the one observed in the primordium and basidioma from bran-based solid medium. The analysis of the overall data allowed designing a general scheme of chitin metabolism and autophagy during M. perniciosa development, focusing on the mycelium phases as crucial and environmentally influenced steps preceding the primordium and basidioma formation. These data support the idea that the nutritional environment of M. perniciosa influences its development and life cycle.

Mining, although relevant and indispensable for human socioeconomic development, is considered one of the most polluting anthropogenic activities. Water resources are the most vulnerable environmental compartment to the direct impacts of mining, especially in the semi-arid regions. In these regions, mining activity constitutes an important challenge in the management of water resources; since its impacts can be maximized by the adverse meteorological conditions. This study aimed to assess the level of contamination in water resources of three important mining areas in a semi-arid region, where approximately 70,000 people live. The concentrations of eleven heavy metals in sediment, surface and groundwater samples were determined by ICP OES. The results obtained for water samples indicated significant contamination by Cd, Pb, and U, based on the limits established by Brazilian and international regulatory legislation. In the case of sediment samples, higher concentrations of Cr, Cu, Ni, and V were observed. Pollution indices (PLI, CF and Igeo) revealed moderate to extreme contamination mainly along the Jacare and Contas rivers. The Pearson correlation, Principal Component, and Hierarchical Cluster analyses were performed to identify patterns in the distribution of elements and common sources of pollution. The results suggested that the concentrations of Co, Cr, Cu, Fe, Mn, Ni, and V were mainly related to mining activities and, to a lesser extent, natural sources. In the case of Cd and Pb, contamination may have an important contribution from fertilizers use, whereas Zn has a mixed source of both lithogenic and anthropogenic origin. On the other hand, the high concentrations of U, specifically in groundwater samples, were associated with geogenic causes. Although the potential ecological risk values indicated a low ecological risk; other sediment quality indices (TEL, PEL, ΣTU, and PEL-Q) revealed that there is 25% of the probability that the content of heavy metals in water resources near the mining areas induces adverse toxic effects on aquatic organisms.

This manuscript approaches the use of mixture design in the optimization of any stage of an analytical method. In addition to addressing the basic principles of this type of design, examples of applications showing the potential of these chemometric tools are presented and discussed. The establishment of constraints and the use of pseudo-components as an artifice to simplify their mathematical modeling are also approached. Finally, a combination of mixture variables with process variables is presented as an alternative for the simultaneous optimization of these types of variables.

In this study, multivariate statistical techniques were used to evaluate concentrations of bioactive compounds such as theobromine, catechin, epicatechin, and caffeine in artisanal and fine chocolate using high-performance liquid chromatography (HPLC). The compound separation optimization step was carried out using a central composite design with three variables. The optimized variables were the initial percentage of methanol in the mobile phase, gradient time and flow rate. The optimal conditions were: initial methanol percentage of 0% (starting with 100% of 0.1% (v/v) acetic acid solution), changing to 100% of methanol in 9.85 min, with a flow rate of 0.74 mL min−1. The optimized procedure was validated and applied to the analysis of artisanal and fine chocolates with varying cocoa content. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to discriminate the samples based on the cocoa content present in the chocolates. Samples containing a high percentage of cocoa solids were separated from those containing a low percentage of cocoa solids due to their high concentrations of methylxanthines and flavonoids. Theobromine, catechin, epicatechin and caffeine concentrations in all samples ranged from 1.6 mg g−1 to 13.9 mg g−1, 0.047 mg g−1 to 0.60 mg g−1, 0.048 mg g−1 to 1.68 mg g−1 and 0.6 mg g−1 to 1.52 mg g−1, respectively. A comparison with data found in the scientific literature showed that artisanal and fine chocolate with a high cocoa content can be a good source of stimulant substances such as caffeine and antioxidant compounds such as catechin and epicatechin.

Environmental cadmium (Cd) sources have increased in mangrove sediments in recent decades, inducing cellular damage to many plants. Avicennia schaueriana is abundant in mangrove sites and has been subject to Cd contamination. The possible effects of Cd toxicity and the structural and physiological disturbances to this plant were studied. Can this plant express early cellular tolerance mechanisms to such metal contamination? Seedlings of A. schaueriana were collected from sites of their natural occurrence, placed in plastic pots containing nutrient solution for 60 days, and subsequently exposed to increasing Cd concentrations for 5 days under experimental conditions. The anatomical, ultrastructural and physiological changes induced by Cd were analysed. Cd accumulated mainly in the root system and in pneumatophores, stems and leaves, induced differential accumulation of mineral nutrients, but did not induce necrosis or changes in leaf anatomy. However, there was a decrease in starch grains and an increase in deposited electron-dense material in the cortex and vascular bundles. Cd induced both increases in calcium (Ca) content in shoots and Ca oxalate crystal precipitation in leaf mesophyll and was detected in crystals and in the secretion of salt glands. Our observations and experimental results provide evidence of Cd tolerance in A. schaueriana. As a new feature, despite the clear cellular physiological disorders, this plant is able to eliminate Cd through leaf salt glands and immobilise it in Ca crystals, representing fast mechanisms for Cd exclusion and complexation in leaves in heavy metal coastal polluted marine ecosystems.

Contamination of medicinal plants with heavy metals as Pb and Cd can affect the growth and the essential oil production of the plants and represent a risk to those who consume as medicine. This study aimed to evaluate the effects of absorption and localization of Pb and Cd on growth, ultrastructural aspects of leaves and essential oil yield and composition of Mentha arvensis, applied on the soil with increasing concentrations (8, 16, 32, 64 and 128mg kg-1). There was a differential absorption of Pb and Cd by M. arvensis mainly concentrated in the roots. Pb was found in small amounts in the leaves while Cd largely exceeded the safety limit without symptoms of toxicity. The ultrastructural analysis revealed the metal accumulation on vesicles surrounding the mitochondria and the presence of electron dense deposits surrounding the mitochondria, nucleus and chloroplasts. Little changes caused by Pb and Cd application were not enough to affect the growth and essential oil yield and composition of M. arvensis

The aim of the study was to evaluate the effect of the arbuscular mycorrhizal fungi (AMF), Acaulospora morrowiae, Rhizophagus clarus and Scutellospora calospora on the growth and essential oil production of Mentha × piperita L. var. citrata plants. The experiment was conducted in a greenhouse with a 5 × 2 factorial design with five mycorrhizal treatments (uninoculated control, Acaulospora morrowiae, Rhizophagus clarus and Scutellospora calospora, and mixture of inocula) and two P levels (60 and 120 mg P dm-3 soil) with six replicates. Plants were harvested after 75 days of growth for evaluation of dry biomass, mycorrhizal colonization of roots, number of spores in soil, nutrient content of leaves, and composition, content and yield of essential oil. The mycorrhizal treatments influenced all the characteristics evaluated, except the number of spores in soil. AMF colonization was most evident at the lowest dose of phosphate fertilizer applied, except for R. clarus, and in all treatments mycorrhizal colonization was above 45%. Colonization also influenced the nutrient content of the leaves of M. piperita var citrata and increased leaf dry biomass. The content and yield of essential oils were higher in plants colonized by AMF fungi with the 60 mg P fertilization dose, except those colonized by R. clarus which had higher essential oil production only with the 120 mg dm-3 P treatment. The two major components in the essential oils for the plants in all the treatments were linalool and linalyl acetate. Key words: Acaulospora, Rhizophagus, Scutellospora, linalool, linalyl acetate, phosphorus fertilization.

A procedure using ICP OES for sample preparation for the determination of copper, iron and manganese in cashew nuts was developed. Constrained simplex-centroid design was applied in the optimization of the digestion in microwave oven procedure, and the results evaluated from topological maps of the Kohonen network. The best proportion evaluated for the digestion of the sample with HNO3, H2O2 and H2O was 10:45:45 (%). With optimized conditions, the detection limits were 0.63, 4.3 and 0.37 mg kg−1, and quantification 2.1, 14 and 1.2 mg kg−1 for Cu, Fe and Mg, respectively. The precision (% RSD) was 1.84, 2.31 and 2.73, for Cu, Fe and Mg, respectively. The procedure proposed had the accuracy confirmed using NIST 1568b (at 95% reliability) and was applied in the samples obtaining concentrations in the range of 10.7–19.4, 44.3–67.2 and 11.0–21.4 mg kg−1 for Cu, Fe and Mg, respectively.

Paullinia cupana, commonly known as guarana, is an Amazonian fruit whose seeds are used to produce the powdered guarana, which is rich in caffeine and consumed for its stimulating activity. The metabolic profile of guarana from the two largest producing regions was investigated using UPLC-MS combined with multivariate statistical analysis. The principal component analysis (PCA) showed significant differences between samples produced in the states of Bahia and Amazonas. The metabolites responsible for the differentiation were identified by orthogonal partial least squares discriminant analysis (OPLS-DA). Fourteen phenolic compounds were characterized in guarana powder samples, and catechin, epicatechin, B-type procyanidin dimer, A-type procyanidin trimer and A-type procyanidin dimer were the main compounds responsible for the geographical variation of the samples.

In this work, it was developed an alternative analytical strategy for the preparation of vegetal samples extracted with diluted acids and assisted by ultrasound and microwave radiation for the determination of nutrients elements by fast sequential flame atomic absorption spectrometer. The conditions optimized using univariate and multivariate methodologies for the procedure were as follows: 200 mg of sample; extraction solution comprising a mixture of 6.3 mL HNO3, 2.1 mL HCl, and 1.7 mL CH3COOH; extractor with a final concentration of 2.5 mol L-1; a sonication time of 30 min; and a microwave radiation time of 6 s. The accuracy of the procedure was confirmed by analyzing the certified reference material NIST 1515 (apple leaves) and by comparison with the results obtained through microwave-assisted total digestion method. The procedure was applied to determine Ca, Mg, Cu, Mn, Fe, and Zn in several cassava peel samples used in animal nutrition, and proved to be simple, reliable, fast, easy to implement, and inexpensive.