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1.
Biochem Biophys Rep ; 38: 101704, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38623537

RESUMO

The Terminalia catappa L. tree is an ornamental and shade tree producter of a large amount of biological waste sent to landfills. Therefore, this plant constitutes so-called municipal solid wood waste (MSWW), which causes undesirable impacts on the environment, such as the generation of methane through the action of microorganisms. Sustainable solutions for the proper use and disposal of MSWW are a topic that has assumed great relevance at present due to the high quantities of MSWW generated worldwide. Pyrolysis constitutes an attractive alternative for the sustainable use of MSWW to produce higher value-added products. This study investigated the slow pyrolysis of Terminalia catappa L. fruit and the use of the aqueous fraction produced for bovine mastitis control. We obtained four fractions from the pyrolysis process, with average yields of the aqueous phase (36.22 ± 2.0 %), bio-oil (5.52 ± 0.4 %), biochar (37.55 ± 2.8 %) and gas (20.71 ± 2.0 %). The aqueous fraction was extracted with organic solvents and analyzed by gas chromatography coupled to mass spectrometry (GC‒MS). The extracts were composed mainly of phenols (50 %), furan derivatives, cyclic ketones, and others with lower contents, such as alcohols and esters. The aqueous fraction had bactericidal activity against Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, which are responsible for bovine mastitis. In addition, the fraction showed low cytotoxicity against a murine melanoma cell line from a C57BL/6J mouse, B16F10 cells and mouse peritoneal cells.

2.
An Acad Bras Cienc ; 81(2): 165-72, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19488620

RESUMO

The main objective of this work is to evaluate the occurrence of bromophenols (2bromophenol, 4bromophenol, 2,4dibromophenol, 2,6dibromophenol and 2,4,6tribromophenol), in the flesh and guts in two species of the LutjanidaeFamily: Lutjanus synagris and Ocyurus chrysurus. The bromophenols were extracted by steam distillation with pentaneether (7:3 v/v), identified by reverse phase High Performance Liquid Chromatography (HPLCUV), and quantified bythe externalstandard method. Total bromophenol concentrations were similar in the muscle of both species, rangingfrom 36 ng g(1) to 349 ng g(1). The total bromophenol concentrations in stomach (ranging from 12 ng g(1) to 586 ng g(1))were slightly higher than in muscle. The presence of bromophenol in the muscles of the species under study may occuras a result of their diet. The results of this work are therefore expected to contribute toward a better understanding ofthe path of bromophenol absorption from the fish's stomach to the rest of its body.


Assuntos
Peixes , Músculos/química , Fenóis/análise , Estômago/química , Animais , Cromatografia Líquida de Alta Pressão
3.
Talanta ; 67(5): 1007-13, 2005 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-18970272

RESUMO

Caffeine (1,3,7-trimethylxanthine), theobromine (3,7-dimethylxanthine) and theophylline (1,3-dimethylxanthine) are the most important naturally occurring methylxanthines. Caffeine is a constituent of coffee and other beverage and included in many medicines. Theobromine and theophylline are formed as metabolites of caffeine in humans, and are also present in tea, cocoa and chocolate products. In order to improve the chromatographic resolution (R(s)) with a good analysis time, experimental designs were applied for multivariate optimisation of the experimental conditions of an isocratic reversed-phase high-performance liquid chromatographic (RP-HPLC) method used for the simultaneous determination of caffeine, theobromine and theophylline. The optimisation process was carried out in two steps using full three-level factorial designs. The factors optimised were: flow rate and mobile phase composition. Optimal conditions for the separation of the three methylxanthines were obtained using a mixture of water/ethanol/acetic acid (75:24:1%, v/v/v) as mobile phase and a flow rate of 1.0mLmin(-1). The RP-HPLC/UV method was validated in terms of limit of detection (LOD), limit of quantitation (LOQ), linearity, recovery and the precision, calculated as relative standard deviation (R.S.D.). In these conditions, the LOD was 0.10mugL(-1) for caffeine, 0.07mugL(-1) for theobromine and 0.06mugL(-1) for theophylline. The proposed method is fast, requires no extraction step or derivatization and was suitable for quantification of these methylxanthines in coffee, tea and human urine samples.

4.
An. acad. bras. ciênc ; 81(2): 165-172, June 2009. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-514650

RESUMO

The main objective of this work is to evaluate the occurrence of bromophenols (2bromophenol, 4bromophenol, 2,4dibromophenol, 2,6dibromophenol and 2,4,6tribromophenol), in the flesh and guts in two species of the LutjanidaeFamily: Lutjanus synagris and Ocyurus chrysurus. The bromophenols were extracted by steam distillation with pentaneether (7:3 v/v), identified by reverse phase High Performance Liquid Chromatography (HPLCUV), and quantified bythe externalstandard method. Total bromophenol concentrations were similar in the muscle of both species, rangingfrom 36 ng g¹ to 349 ng g¹. The total bromophenol concentrations in stomach (ranging from 12 ng g¹ to 586 ng g¹)were slightly higher than in muscle. The presence of bromophenol in the muscles of the species under study may occuras a result of their diet. The results of this work are therefore expected to contribute toward a better understanding ofthe path of bromophenol absorption from the fish's stomach to the rest of its body.


O principal objetivo do presente trabalho foi o estudo de bromofenóis (2bromofenol, 4bromofenol, 2,4dibromofenol,2,6dibromofenol and 2,4,6tribromofenol), no músculo e estômago de duas espécies de peixes da Familia Lutjanidae: Lutjanus synagris e Ocyurus chrysurus. Os bromofenóis foramextraídos através de destilação por arraste a vapor com pentanoéter (7:3 v/v), analisados por Cromatografia Líquida de AltaEficiência e quantificados por padronização externa. As concentrações totais de bromofenóis no músculo de ambas as espécies foram similares e estiveram na faixa de 36 ng g¹ a349 ng g¹. As concentrações totais de bromofenóis no estômago (na faixa de 12 ng g¹ a 586 ng g¹) foram mais altas queno músculo. A presença de bromofenóis no músculo das espécies estudadas pode ter origem na dieta. Os resultados destetrabalho contribuirão para o melhor entendimento das rotas deabsorção de bromofenóis nos peixes.


Assuntos
Animais , Peixes , Músculos/química , Fenóis/análise , Estômago/química , Cromatografia Líquida de Alta Pressão
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