Abstract Honey is a food of nutritional, medicinal and commercial importance. The physicochemical characteristics, pollen spectrum and mineral composition of eighteen honey samples obtained from regions (Cachoeira, Coqueiros, Maragojipe and Santiago do Iguape) near the Paraguaçu River, Bahia, Brazil were evaluated. Botanical families Asteraceae, Leguminosae, Malvaceae, Myrtaceae and Palmae were most frequently found. Five samples had water contents above the maximum limit established by the Brazilian legislation (> 20%). The mineral composition was determined by ICP OES, after microwave digestion. Ca, K, Mg and Na were measured (mg Kg-1) in the range from: 18.85 to 79.61; 366.74 to 1214.98; 12.46 to 44.59 and 11.56 to 85.39, respectively. Cu, Fe, Mn and Zn had variable concentration ranges, between 0.05 and 6.13 mg Kg-1. Al, Ba, Cd, Co, Cr, Ni, Pb, Se and V showed values below the LOD. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) demonstrated that there are no similarities of mineral composition among honey samples.

In this study, inductively coupled plasma optical emission spectrometry (ICP OES) was used for multi-element analysis in five multimineral preparations from a dissolution test, in accordance with the United States Pharmacopeia (USP 34 method): apparatus 1, 75 rpm and 900 mL of 0.1 mol L-1 HCl. Element releases in all samples (minimum-maximum in %) were: Ca (14.5-28.2), Cr (54.5-68.0), Cu (2.9-10.0), Fe (4.0-34.3), Mg (6.0-25.2), Mn (2.6-51.2), V (0.0-51.4) and Zn (1.5-107.3). The concentrations of Al, Ba, Cd, Co, Mo, Pb and Se were below the limit of detection of ICP OES. Accuracy was assessed by microwave digestion and recovery values of 94-102%. USP 34 method indicates that not less than 75% of the elements described on the product label must be dissolved in 1 h. Only the release of Zn met the recommendations. The results indicated the need for greater quality control in multivitamin preparations. The dissolution test was validated in order to contribute to Brazilian and other pharmacopoeias.

Desenvolveu-se um procedimento para determinação de cobre, ferro, chumbo e zinco em amostras de gasolina. O procedimento foi baseado na pré-concentração dos metais empregando uma resina modificada com o ácido 3,4-dihidroxibenzóico (XAD-DHB), seguida da dessorção com solução ácida. Os analitos no eluato foram determinados por espectrometria de absorção atômica em chama multielementar seqüencial (FS-FAAS). As amostras de gasolina foram preparadas como microemulsões misturando-se 80 mL de amostra com 17 mL de propan-1-ol e 3 mL de solução tampão (pH 10). As variáveis físico-químicas que influenciam no processo de extração foram otimizadas. Os LODs obtidos foram 2,2 µg L-1 para Fe, 3,1 µg L-1 para Cu, 2,3 µg L-1 para Pb, e 2,6 µg L-1 para Zn. Os valores de RSDs das concentrações dos analitos nas amostras enriquecidas com 0,05 e 0,1 mg L-1 de cada metal variaram de 5,8 a 9,7%. As recuperações variaram de 82 a 99%. O método foi aplicado na determinação dos analitos em níveis de µg L-1 em amostras de gasolinas coletadas em postos revendedores de Salvador, BA, Brasil.

A procedure was developed for determination of copper, iron, lead and zinc in gasoline. The procedure was based on the preconcentration of metals using a resin modified with 3,4-dihydroxybenzoic acid (XAD-DHB), followed by desorption with an acid eluent. The components in the eluate were then determined by fast sequence flame atomic absorption spectrometry (FS-FAAS). The gasoline samples were prepared as microemulsions by mixing 80 mL of sample with 17 mL of propan-1-ol and 3 mL of a buffer solution (pH 10). The chemical and physical variables influencing the extraction were optimized. The LODs obtained were 2.2 µg L-1 Fe, 3.1 µg L-1 Cu, 2.3 µg L-1 Pb and 2.6 µg L-1 Zn. The RSDs ranged from 5.8 to 9.7% in samples spiked with 0.05 and 0.1 mg L-1 of each metal and recoveries varied from 82 to 99%. The procedure was suitable for determination of the analytes at µg L-1 levels in gasoline samples collected from several gas stations in Salvador, State of Bahia, Brazil.

Neste trabalho foi avaliada a eficiência de dois procedimentos para digestão ácida de amostras de biodiesel visando à determinação de Ca, P, Mg, K e Na por espectrometria de emissão óptica com plasma acoplado indutivamente com configuração axial (ICP OES). Nas digestões em sistema aberto, foi utilizada a mistura contendo ácidos nítrico, sulfúrico e peróxido de hidrogênio e aquecimento condutivo; enquanto que no procedimento empregando forno de microondas com cavidade foi utilizada a mistura contendo ácido nítrico e peróxido de hidrogênio. Os procedimentos foram avaliados considerando-se limites de quantificação, precisão, acidez final dos digeridos e teor de carbono residual. Os teores de carbono residual nos digeridos foram 0,358 ± 0,012% para o sistema aberto com aquecimento convencional e 0,614 ± 0,023% para o sistema fechado com aquecimento assistido por radiação microondas, o que demonstra a alta eficiência dos procedimentos propostos. O sistema de digestão em forno de microondas com cavidade resultou em maior rapidez, segurança e resultados analíticos com percentuais de recuperação de 89,0-103,0% e desvios menores que 5%. Os limites de detecção obtidos, < 0.40 µg g-1, são adequados para a determinação dos analitos, conforme os limites estabelecidos na legislação brasileira. Três amostras de biodiesel produzidas de diferentes fontes foram analisadas. Em comparação com outros procedimentos propostos na literatura, o procedimento desenvolvido usando forno de microondas com cavidade apresenta vantagens, tais como não necessitar de soluções orgânicas para calibração e não usar solventes orgânicos tóxicos.

In the present work, the efficiency of two procedures for the digestion of biodiesel was investigated for the simultaneous determination of Ca, P, Mg, K and Na by axial view ICP OES. In the open system with conventional heating, concentrated nitric and sulfuric acids were added to the samples, and the addition of hydrogen peroxide completed the digestion. In the microwave-assisted closed system, complete digestion was performed using concentrated nitric acid and hydrogen peroxide. The analytical performances were evaluated through limits of quantification, precision of the overall procedures, final acidity of the digests, and residual carbon contents. The contents of residual carbon for the biodiesel samples digested were 0.358 ± 0.012% using the open system with conventional heating and 0.614 ± 0.023% using the microwave-assisted closed vessel system, demonstrating the high efficiency of both proposed procedures. The optimized microwave-assisted decomposition procedure produced the fastest, safest and most accurate analytical results with recoveries of 89.0-103.0% and deviations lower than 5% in most cases. Low limits of detection were obtained (< 0.40 µg g-1), adequate for the established limits set out in Brazilian legislation for these analytes. Three biodiesel samples produced from different oil sources were analyzed. In comparison with other procedures proposed in the literature, the developed procedure using the microwave-assisted closed system is advantageous because it neither require organic standard solutions for calibrations nor use toxic organic solvents.

Neste trabalho descreve-se a composição mineral das folhas de Lippia alba (Mill.) que são utilizadas na preparação de chá utilizado na medicina popular. Assim, as folhas da espécie foram coletadas em cidades brasileiras e as amostras foram digeridas usando ácido nítrico e peróxido de hidrogênio em placa aquecedora e, em seguida, foram analisadas empregando espectrometria de emissão óptica com plasma acoplado indutivamente (ICP OES). Para avaliação da exatidão foi utilizado o material de referência certificado, folhas de maçã - NIST SRM 1515. Os resultados demonstraram que cálcio, magnésio e fósforo têm conteúdo médio de 1.950, 2.856 e 2.335 mg 100 g-1 e variações de concentrações de 767-3.887, 314-8.591 e 247-9.214 mg 100 g-1, respectivamente. Os micro-elementos, bário, zinco, cobre, ferro, manganês e níquel têm conteúdos médios de 2,16; 2,95; 0,94; 11,2; 4,25 e 0,09 mg 100 g-1, para variações de concentrações de 0,66-7,1; 1,35-6,3; 0,33-1,7; 0,98-34; 0.82-7,4 e 0,03-0,15 mg 100 g-1, respectivamente. Os dados foram também avaliados usando análise de componentes principais (PCA).

Leaves of Lippia alba (Mill.) N.E. Brown are used for the preparation of tea infusions that are employed in folk medicine. In this paper, the mineral composition of Lippia alba (Mill.) leaves, collected from different Brazilian cities, was evaluated. The samples were digested using nitric acid and hydrogen peroxide on a hot plate and were analyzed using inductively coupled plasma optical emission spectrometry (ICP OES). SRM 1515 apple leaves from NIST were used for checking accuracy. The results demonstrated that calcium, magnesium and phosphorus have average contents of 1,950, 2,856 and 2,335 mg 100 g-1, respectively, and concentration ranges of 767-3,887, 314-8,591 and 247-9,214 mg 100 g-1, respectively. The microelements barium, zinc, copper, iron, manganese and nickel have average contents of 2.16, 2.95, 0.94, 11.2, 4.25 and 0.09 mg 100 g-1, respectively, and concentration ranges of 0.66-7.1, 1.35-6.3, 0.33-1.7, 0.98-34, 0.82-7.4 and 0.03-0.15 mg 100 g−1, respectively. The data were also evaluated using principal component analysis (PCA).

Uma análise de variância de três fatores foi usada para testar a significância do tipo de recipiente, tipo de material e número de replicatas na preparação de amostras de sedimento utilizando um banho ultra-sônico. A extração convencional com HCl 1,0 mol L-1, por 0,5, 4 e 12 h, foi modificada, e o banho ultra-sônico foi aplicado para diminuir o tempo de preparo de amostras. Os metais traço foram medidos por ICP OES. Os melhores resultados foram obtidos com frascos de Teflon® com base plana. Com exceção do Ni, constatou-se que é possível trabalhar no banho de ultrasom em triplicatas, sem comprometer a eficiência e/ou precisão da extração. A eficiência de extração melhorou com o aumento no tempo de sonicação de 1 para 50 min. Para a maioria dos elementos, a extração assistida por radiação ultra-sônica pode reduzir o tempo convencional de extração de 12 h para 50 min ou menos (i.e. 6 min para Pb). A precisão obtida foi comparável aos valores obtidos com a extração convencional. O método proposto é rápido, barato e uma boa alternativa para o levantamento da biodisponibilidade e potencial de mobilidade de metais em sedimentos.

A three factors analysis of variance was used to test the significance of the type of vessel, the type of material and the number of replicates in the preparation of sediment samples using an ultrasonic bath. The conventional extraction with HCl 1.0 mol L-1, for 0.5, 4 and 12 h, has been modified, applying an ultrasonic bath, in order to speeding up the sample preparation time. Trace metals were measured by an ICP OES. The best results were obtained using a Teflon® vessel with a flat bottom. For all metals but Ni it was demonstrated the feasibility of working in triplicates in the ultrasonic bath, without compromising the efficiency and/or the precision of the extraction. Leaching efficiency enhanced with increasing sonication time from 1 to 50 min. For most elements the ultrasound-assisted leaching could reduce the conventional extraction time from 12 h to 50 min or even less (i.e. 6 min for Pb). The precision obtained was comparable to values obtained for the conventional acid extraction. The proposed method is a fast, inexpensive and easy alternative for screening of the potential mobility and bioavailability of metals in sediments.

Contextualized overview of the Biodiesel Production Chain, from the lab bench to the industry, with critical evaluation of state-of-art and technological development through scientific articles and patents, focusing on feedstock, reaction/production, first and second generation processes, specification and quality, transport, storage, co-products (effluents and sub-products), and emissions. Challenges are identified and solutions are proposed based on the Brazilian feedstock, edaphoclimatic conditions, process monitoring in remote regions, state policy, and environment preservation, among others. Forecasts are made based on the technology assessment, identifying future trends and opportunities for R&D&I.