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1.
Toxins (Basel) ; 15(9)2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37755945

RESUMO

Aflatoxins can cause intoxication and poisoning in animals and humans. Among these molecules, aflatoxin B1 (AFB1) is the most dangerous because of its carcinogenic and mutagenic properties. To mitigate these effects, clay adsorbents are commonly included in the diet of animals to adsorb the carcinogens and prevent their absorption in the gastrointestinal tract. In this study, four clays, three smectites (C-1, C-2, and C-3), and one zeolite (C-4), were compared as adsorbents of AFB1 and trace inorganic nutrients using an in vitro gastrointestinal model for poultry. Characterization of the clays using Fourier transform infrared spectroscopy revealed characteristic bands of smectites in C-1, C-2, and C-3 (stretching vibrations of Si-O, Al-O-Si, and Si-O-Si). The C-4 presented bands related to the bending vibration of structural units (Si-O-Si and Al-O-Si). X-ray diffraction analysis showed that C-1 is a montmorillonite, C-2 is a beidellite, C-3 is a beidellite-Ca-montmorillonite, and C-4 is a clinoptilolite. The elemental compositions of the clays showed alumina, silica, iron, calcium, and sodium contents. The cation exchange capacity was higher in C-3 clay (60.2 cmol(+)/kg) in contrast with the other clays. The AFB1 adsorption of C-1 was the highest (98%; p ˂ 0.001), followed by C-2 (94%). However, all the clays also sequestered trace inorganic nutrients (Fe, Mn, Zn, and Se). Both smectites, montmorillonite and beidellite, were the most suitable for use as adsorbents of AFB1.


Assuntos
Oligoelementos , Animais , Humanos , Adsorção , Aflatoxina B1 , Argila , Bentonita , Aves Domésticas , Carcinógenos
2.
Mar Environ Res ; 186: 105922, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36812839

RESUMO

Functional aspects of biological communities influence ecosystem processes and it is urgent to understand how human disturbances affect functional diversity and ecosystem functions and services. Our purpose was to address the use of different functional metrics of nematode assemblages to evaluate the ecological status of tropical estuaries subjected to different human activities, aiming to advance and improve the knowledge about the usefulness of functional attributes as indicators of environmental quality. Three approaches were compared: functional diversity indexes, single trait, and multi traits using the Biological Traits Analysis. The RLQ + fourth-corner combined method was used to identify relationships among functional traits, inorganic nutrients, and metals concentrations. Lower values of FDiv, FSpe, and FOri indicate a convergence of functions, characterizing impacted conditions. A dominant set of traits was related to disturbance, mainly inorganic nutrient enrichment. All the approaches allowed for the detection of disturbed conditions, however, multi traits was the most sensitive one.


Assuntos
Ecossistema , Nematoides , Animais , Humanos , Biodiversidade , Biota , Estuários
3.
Integr Environ Assess Manag ; 18(3): 796-812, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34524737

RESUMO

The anthropogenic discharges of inorganic nutrients impact water quality, affecting the macroinvertebrate assemblage and food safety. The main objective of this study was to examine the seawater quality and macroinvertebrate dynamics in muddy habitats of Buenaventura Bay, Colombian Pacific. Macroinvertebrates were captured using artisanal trawl nets during different seasons and along four sampling sites. Multivariate analyses (canonical correspondence analysis and generalized additive model) were used to assess the effects of variations in nitrite, nitrates, phosphate concentrations, and physicochemical variables (salinity, pH, dissolved oxygen [DO], temperature, and total dissolved solids [TDS]) of water on the macroinvertebrate assemblage. Richness was the highest at sites with high salinity and temperature and low concentrations of nitrites and TDS. The densities of the commercial shrimp species Xiphopenaeus riveti and Rimapenaeus byrdi were the highest at sites with higher DO and alkalinity, and lower nitrate concentrations. The swimming crab Callinectes arcuatus was dominant at sites with low water quality. In summary, in the transitional season and at the inner sites of Buenaventura Bay, it was observed the lowest water quality due to high nitrate concentration. High nitrate concentration was highlighted as the main anthropogenic factor that could decrease the capture of target macroinvertebrate species for food and livelihoods of artisanal fishermen and their families. Thus, macroinvertebrate communities may be vulnerable to increased inorganic nutrient inputs, which could affect estuarine water quality and ecosystems services. Integr Environ Assess Manag 2022;18:796-812. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Estuários , Qualidade da Água , Animais , Baías , Ecossistema , Monitoramento Ambiental , Humanos , Invertebrados , Nitratos , Rios
4.
Braz J Microbiol ; 51(3): 1159-1168, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32078731

RESUMO

We studied petroleum biodegradation by biostimulation by using water in oil in water (W/O/W) double emulsions. These emulsions were developed using seawater, canola oil, surfactants, and mineral salts as sources of NPK. The emulsions were used in the simulation of hydrocarbon bioremediation in oligotrophic sea water. Hydrocarbon biodegradation was evaluated by CO2 emissions from microcosms. We also evaluated the release of inorganic nutrients and the stability of the emulsion's droplets. The double emulsions improved CO2 emission from the microcosms, suggesting the increase in the hydrocarbon biodegradation. Mineral nutrients were gradually released from the emulsions supporting the hydrocarbon biodegradation. This was attributed to the formation of different diameters of droplets and therefore, varying stabilities of the droplets. Addition of the selected hydrocarbonoclastic isolates simulating bioaugmentation improved the hydrocarbon biodegradation. We conclude that the nutrient-rich W/O/W emulsion developed in this study is an effective biostimulation agent for bioremediation in oligotrophic aquatic environments.


Assuntos
Bactérias/metabolismo , Hidrocarbonetos/metabolismo , Petróleo/metabolismo , Água do Mar/microbiologia , Poluentes Químicos da Água/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Emulsões/análise , Emulsões/metabolismo , Petróleo/análise , Água do Mar/análise , Poluentes Químicos da Água/análise
5.
R. Inst. Adolfo Lutz ; 66(2): 113-119, 2007.
Artigo em Português | VETINDEX | ID: vti-452513

RESUMO

In this investigation a wet digestion technique (HCl hydrolysis) of raw bean (Phaseolus vulgaris) was validated in order to perform the simultaneous determination of inorganic nutrients Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn by means of inductively coupled argon plasma optical emission spectrometry (ICPOES). This simple, relatively rapid, and with satisfactory performance characteristics technique was employed for analyzing 40 raw bean marketed in São Paulo state (Brazil). After determining inorganic nutrients by emission spectrometry, the obtained concentrations of Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn contents (in mg/100g bean) were 120±20; 0.8±0.1; 6.0±0.9; 1370±80; 170±10; 1.5±0.4; 1.4±0.4; 350±50; and 2.6±0.3, respectively. These inorganic nutrients contents are in agreement with the information from six food composition tables, except of Na that showed a significantly lower value. The results were also used to estimate the bean consumption contribution in Recommended Daily Intakes (RDI) for the investigated nutrients, and it was noted that bean can significantly contribute in Cu, Mg, Mn, P, Fe, and Zn RDIs.


Neste trabalho foi validada a técnica de digestão por via úmida (hidrólise com HCl) de feijão (Phaseolus vulgaris), para efetuar a determinação simultânea dos nutrientes inorgânicos Ca, Cu, Fe, K, Mg, Mn, Na, P e Zn, por espectrometria de emissão óptica com plasma de argônio indutivamente acoplado (ICPOES). Essa técnica simples, relativamente rápida e com características satisfatórias de desempenho, foi utilizada na preparação de 40 amostras de feijão cru comercializadas no estado de São Paulo, Brasil. Após a determinação das concentrações dos nutrientes inorgânicos por ICP OES, os teores obtidos (emmg/100g de feijão) de Ca, Cu, Fe, K, Mg, Mn, Na, P e Zn foram, respectivamente, de 120±20; 0,8±0,1; 6,0±0,9; 1370±80; 170±10; 1,5±0,4; 1,4±0,4; 350±50; 2,6±0,3. Esses teores mostraram-se satisfatoriamente concordantes com as informações de seis tabelas de composição de alimentos, com a exceção do teor de sódio que apresentou-se significativamente menor. Os resultados também foram usados para estimar a contribuição do consumo de feijão na Ingestão Diária Recomendada (IDR) dos nutrientes investigados, constatando-se que o feijão pode contribuir significativamente principalmente nas IDRs do Cu, Mg, Mn, P e Fe.

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