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1.
Int. j. morphol ; 42(4): 977-983, ago. 2024. ilus
Artigo em Inglês | LILACS | ID: biblio-1569274

RESUMO

SUMMARY: BPA is a multifunctional endocrine disruptor with ubiquitous presence in aquatic ecosystems. The Mexican Central Plateau is an area severely impacted by pollution, inhabited by endemic viviparous fish. However, efforts to understand the effects of BPA on native species such as Goodea atripinnis are non-existent. This study focused on providing in vivo evidence of alterations in the testes of G. atripinnis males due to acute exposure to BPA at test concentrations of 1 mg/L, 10 mg/L, and 50 mg/L for 96 h. BPA exposition 1 mg/L and 10 mg/L showed degeneration and disorganization in germinal tissue. Furthermore, there was a notable decrease in sperm within the seminiferous tubules of males exposed to 10 mg/L of BPA. In all treatments, somatic cells had alterations by connective tissue thickening and an increase in collagen fibers. Additionally, inflammation and bleeding occurred in the testes of males exposed to 1 and 10 mg/L BPA. The alterations in the testes of G. atripinnis are related to BPA toxicity, which can lead to apoptosis in germ cells increasing connective tissue. Finally, even though the changes produced by BPA became evident in acute exposure (96 h), its effects are probably irreversible, compromising the reproduction of G. atripinnis.


El BPA es un disruptor endocrino multifuncional con presencia ubicua en los ecosistemas acuáticos. La Meseta Central mexicana habitada por peces vivíparos endémicos, es una zona severamente impactada por la contaminación. Sin embargo, los esfuerzos por comprender los efectos del BPA en especies nativas como Goodea atripinnis son inexistentes. Este estudio se centró en proporcionar evidencia in vivo de alteraciones en los testículos de machos de G. atripinnis debido a la exposición aguda al BPA en concentraciones de prueba de 1 mg/L, 10 mg/L y 50 mg/L durante 96 h. La exposición a BPA 1 mg/L y 10 mg/L mostró degeneración y desorganización en el tejido germinal. Además, hubo una disminución notable de los espermatozoides dentro de los túbulos seminíferos de machos expuestos a 10 mg/L de BPA. En todos los tratamientos las células somáticas presentaron alteraciones por engrosamiento del tejido conectivo y aumento de las fibras de colágeno. Además, se produjo inflamación y sangrado en los testículos de machos expuestos a 1 y 10 mg/L de BPA. Las alteraciones en los testículos de G. atripinnis están relacionadas con la toxicidad del BPA, lo que puede provocar apoptosis en las células germinales aumentando el tejido conectivo. Finalmente, si bien los cambios producidos por el BPA se hicieron evidentes en la exposición aguda (96 h), sus efectos probablemente sean irreversibles, comprometiendo la reproducción de G. atripinnis.


Assuntos
Animais , Fenóis/toxicidade , Testículo/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Ciprinodontiformes , Testículo/patologia , Disruptores Endócrinos , Peixes
2.
Sci Total Environ ; 951: 175551, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39151623

RESUMO

Despite being one of the most remote areas on the planet, the Antarctic continent is subject to anthropogenic influences. The presence of various groups of contaminants, including persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), has been documented in the region over the past decades. However, a significant knowledge gap remains regarding the detection of new pollutants, such as emerging contaminants (ECs), in Antarctic coastal environments. This study analyzed the occurrence and levels of selected POPs, PAHs, ECs in surface sediments from Admiralty Bay, Antarctica Peninsula. Non-target screening was employed to identify potential novel contaminants in the region. Samples (n = 17) were extracted using an accelerated solvent extraction (ASE) system and instrumental analyses were performed using gas chromatography coupled to a triple-quadrupole mass spectrometer (GC/MS-MS). Regarding regulated contaminants, concentrations of Σ5PCBs ranged from

3.
Environ Sci Pollut Res Int ; 31(39): 51991-52000, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39136921

RESUMO

As lithium (Li) stands out as a crucial component of batteries, the inappropriate disposal of electronic gadgets might drive Li pollution in environmentally sensitive environments, such as dumps, where castor bean (Ricinus communis) plant communities are usually found. The exposure to high Li concentration is potentially harmful to the environment and humans. Therefore, it is opportune to evaluate the potential of bioindicator species to monitor Li contamination. In this scenario, the present study assessed the effects of Li exposure on the development of castor bean plants exposed to lithium chloride at five Li dosages (0, 5, 10, 20, and 30 mg dm-3). Significant symptoms of phytotoxicity were observed at all doses. Li dosage exhibited increasing impairment effects on plant biometrics, such as stem diameter and the number of leaves, as well as on the SPAD index, nutritional balance, and biomass production. Our findings suggest castor bean as a potential model species for biomonitoring Li-contaminated areas.


Assuntos
Lítio , Ricinus communis , Ricinus communis/efeitos dos fármacos , Lítio/toxicidade , Monitoramento Ambiental/métodos , Ricinus/efeitos dos fármacos , Poluentes do Solo/toxicidade
4.
Environ Monit Assess ; 196(9): 813, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145782

RESUMO

The presence of microplastics in freshwater systems can have harmful effects on the food chain. Zooplankton, especially suspension and filter feeders, can ingest microplastics, which can cause adverse effects and transfer them to higher trophic levels. Here, we analyze the presence, abundance, and distribution of microplastics in surface water, zooplankton, and fish in two tropical lakes in central Mexico. We collected water samples in triplicate at three sites in each lake and 120 fish of the genus Chirostoma. From each water sample, 300 rotifers and 150 microcrustaceans were randomly isolated and processed independently. Of the particles found in the water, zooplankton, and fish from both lakes, the fragments were the predominant ones. The total abundance of microplastics in the water column of both lakes varied between 1.2 and 17.0 items L-1. In zooplankton, fragments were found predominantly with up to 0.1 items ind-1, while in fish, up to 4.5 items ind-1 was recorded. Our results confirm the presence of microplastics in different compartments of the food webs of freshwater bodies, water column, zooplankton, and fish. Further work is required on the possible effects of these stressors at the different trophic levels.


Assuntos
Monitoramento Ambiental , Peixes , Lagos , Microplásticos , Poluentes Químicos da Água , Zooplâncton , Animais , Lagos/química , México , Poluentes Químicos da Água/análise , Microplásticos/análise , Cadeia Alimentar
5.
Environ Technol ; : 1-12, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092595

RESUMO

This is the first record on literature to use biochar as support for CoFe2O4 to applicate and evaluate it as photocatalyst for degradation of organic pollutants. The support was verified by XRD, FT-IR, SEM, EDS and band gap. Composites CFO1BQ3, CFO1BQ1, and CFO3BQ1 showed 100% degradation in 60 min. This outstanding performance can be related to the drop in band gap energy and recombination rate of e¯/h + . The composites showed better efficiency when compared to pure CoFe2O4 (∼78%). This might be associate to the fact that biochar has a high concentration of phenolic, hydroxyl and carboxylic functional groups on its surface. In this reaction h+, O2•-, and •OH were the reactive species involved in the degradation. The toxicity of ponceau was tested before and after the treatment, through biochemical biomarkers in Danio rerio fish. In general, the treatment proved to be efficient in reducing ponceau toxicity in D. rerio fish.

6.
Sci Rep ; 14(1): 18139, 2024 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103398

RESUMO

In Southeast Asia (SEA) fastidious fungi of the Ceratobasidium genus are associated with proliferation of sprouts and vascular necrosis in cacao and cassava, crops that were introduced from the tropical Americas to this region. Here, we report the isolation and in vitro culture of a Ceratobasidium sp. isolated from cassava with symptoms of witches' broom disease (CWBD), a devastating disease of this crop in SEA. The genome characterization using a hybrid assembly strategy identifies the fungus as an isolate of the species C. theobromae, the causal agent of vascular streak dieback of cacao in SEA. Both fungi have a genome size > 31 Mb (G+C content 49%), share > 98% nucleotide identity of the Internal Transcribed Spacer (ITS) and > 94% in genes used for species-level identification. Using RNAscope® we traced the pathogen and confirmed its irregular distribution in the xylem and epidermis along the cassava stem, which explains the obtention of healthy planting material from symptom-free parts of a diseased plant. These results are essential for understanding the epidemiology of CWBD, as a basis for disease management including measures to prevent further spread and minimize the risk of introducing C. theobromae via long-distance movement of cassava materials to Africa and the Americas.


Assuntos
Genoma Fúngico , Manihot , Doenças das Plantas , Manihot/microbiologia , Doenças das Plantas/microbiologia , Sudeste Asiático , Filogenia , Basidiomycota/genética , Basidiomycota/isolamento & purificação
7.
Front Vet Sci ; 11: 1448165, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39135898

RESUMO

[This corrects the article DOI: 10.3389/fvets.2023.1266499.].

8.
Sci Rep ; 14(1): 18101, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103455

RESUMO

In this study, PROP adsorption was investigated using activated carbon derived from Bactris Guineensis residues and physical statistical modeling. The characterization results indicate high specific surface areas (624.72 and 1125.43 m2 g-1) and pore diameters (2.703 and 2.321 nm) for the peel and stone-activated carbon, respectively. Adsorption equilibrium was investigated at different temperatures (298 to 328 K), and it was found that the adsorption capacity increased with temperature, reaching maximum values of 168.7 and 112.94 mg g-1 for the peel and stone-activated carbon, respectively. The application of physical statistical modeling indicates that a monolayer model with one energy site is adequate for describing both systems, with an R2 above 0.986 and a low BIC of 20.021. According to the steric parameters, the density of molecules per site tends to increase by 116.9% for the stone and 61.6% for the peel. In addition, the model indicates that the number of molecules decreases with increasing temperature from 1.36 to 0.81 and from 1.03 to 0.82. These results indicate that temperature controls the number of receptor sites and the orientation in which propranolol is adsorbed at the surface. The adsorption energies were similar for both systems (approximately 10 kJ mol-1), which indicates that the adsorption occurred due to physical interactions. Finally, the application of thermodynamic potential functions indicates that the maximum entropy is reached at concentrations of half-saturation (Ce 3.85 and 4.6 mg L-1), which corresponds to 1.60 × 10-18 and 1.86 × 10-18 kJ mol-1 K-1 for the stone and peel, respectively. After this point, the number of available sites tends to decrease, which indicates the stabilization of the system. The Gibbs energy tended to decrease with increasing concentration at equilibrium, reaching minimum values of - 1.73 × 10-19 and - 1.99 × 10-19 kJ mol-1, respectively. Overall, the results obtained here further elucidate how the adsorption of propranolol occurs for different activated carbons from the same source.

10.
Environ Toxicol Chem ; 43(10): 2199-2210, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39073366

RESUMO

We investigated the occurrence and the environmental risk of eight contaminants of emerging concern (CECs; acetaminophen, naproxen, diclofenac, methylparaben, 17ß-estradiol, sulfathiazole, sulfadimethoxine, and sulfamethazine) in three Brazilian water bodies, namely, the Monjolinho River Basin (São Paulo State), the Mogi Guaçu River (São Paulo State), and the Itapecuru River (Maranhão State) in three sampling campaigns. The CECs were only quantified in surface water samples collected at the Monjolinho River Basin. Acetaminophen, naproxen, and methylparaben were detected in the range of <200 to 575.9 ng L-1, <200 to 224.7 ng L-1, and <200 to 303.6 ng L-1, respectively. The detection frequencies of the three measured compounds were between 33% and 67%. The highest concentrations of CECs were associated with intense urbanization and untreated sewage discharge. Furthermore, CEC concentrations were significantly correlated with total organic carbon, electrical conductivity, and dissolved oxygen levels, suggesting that domestic pollution from urban areas is an important source in the distribution of CECs in the Monjolinho River Basin. The environmental risk assessment indicated a high risk for acetaminophen (risk quotient [RQ] values between 2.1 and 5.8), a medium risk for naproxen (RQs between 0.6 and 0.7), and a low risk for methylparaben (RQs < 0.1) to the freshwater biota of the Monjolinho River Basin. Our findings show potential threats of CECs in Brazilian water bodies, especially in vulnerable areas, and reinforce the need for improvements in environmental regulations to include monitoring and control of these compounds in aquatic systems. Environ Toxicol Chem 2024;43:2199-2210. © 2024 SETAC.


Assuntos
Monitoramento Ambiental , Rios , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Medição de Risco , Brasil , Rios/química , Parabenos/análise , Acetaminofen/análise , Naproxeno/análise
11.
Food Chem ; 460(Pt 1): 140522, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39047492

RESUMO

This study evaluated the effect of dielectric barrier discharge (DBD) and glow discharge (glow) cold plasma treatments in color, sugars, organic acids, phenolics (concentration and bioaccessibility), antioxidant activity, volatiles, and microbiota of edible mini-roses. Plasma treatments did not affect the flowers' color, while they increased organic acids and phenolics. Flowers treated with DBD had a higher concentration of most phenolics, including hesperidin (84.04 µg/g) related to antioxidant activity, and a higher mass fraction of most volatiles, including octanal (16.46% after 5 days of storage). Flowers treated with glow had a higher concentration of pelargonidin 3,5-diglucoside (392.73 µg/g), greater bioaccessibility of some phenolics and higher antioxidant activity. Plasma treatments reduced the microbiota diversity in mini-roses. Regardless of the plasma treatment, phylum Proteobacteria, family Erwiniaceae, and genus Rosenbergiella were the dominant groups. Results indicate plasma treatments as promising technologies to improve the quality and increase phenolic and specific volatile compounds in mini-roses.


Assuntos
Bactérias , Microbiota , Fenóis , Gases em Plasma , Compostos Orgânicos Voláteis , Fenóis/metabolismo , Fenóis/química , Gases em Plasma/farmacologia , Gases em Plasma/química , Bactérias/metabolismo , Bactérias/classificação , Bactérias/isolamento & purificação , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Antioxidantes/metabolismo , Antioxidantes/química , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Flores/química , Flores/metabolismo
12.
Foods ; 13(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38998481

RESUMO

Consumer perception of foods processed by emerging technologies has been scarcely studied. This study aimed to evaluate the perception of vegan and non-vegan consumers regarding probiotic almond-fermented beverages processed by ultrasound using the packaging of the products (pasteurized/conventional, processed by ultrasound, and processed by ultrasound with a claim on the label). A "Check All That Apply" test with emojis and the Food Technology Neophobia scale were used. The "processed by ultrasound" information did not impact the purchase intention and the perception of healthiness, safety, nutrition, environmental impact, flavor, texture, and price of the products. The claim inclusion increased the perceived acceptability and purchase intention and improved the emotional profile. The vegan consumers showed a more positive perception of ultrasound processing, resulting in increased perceived acceptability, higher citation frequency of positive emoji, and lower sums for the neophobia scale. Vegan and non-vegan consumers agreed that the most important attributes for consumer acceptance are almond aroma, flavor, and consistency. In conclusion, the "processed by ultrasound" information did not negatively impact the acceptability and emotional profile of probiotic almond-fermented beverages, and using a claim on the label may improve consumer perception of the products.

13.
Environ Sci Pollut Res Int ; 31(32): 45177-45191, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38961017

RESUMO

The intensification of livestock farming can pose risks to the environment due to the increased use of veterinary products and the generation of waste in confined areas. The quality of water bodies near livestock establishments (Areco River (A) and Doblado stream (D), San Antonio de Areco, Buenos Aires, Argentina) was studied by physicochemical parameters, metals, pesticides, emerging contaminants, and lethal and sublethal toxicity (neurotoxicity and oxidative stress) in larvae of the native amphibian Rhinella arenarum. Six sites were selected: upstream (S1A and S1D), at the level (S2A and S2D), and downstream (S3A and S3D) from the establishments. A low concentration of dissolved oxygen was observed in Doblado stream (< 2.34 mg/L). Cu, Mn, V, and Zn exceeded the limits for the protection of aquatic life at various sites. Between 24 and 34 pesticides were detected in all sites, with 2,4-D, atrazine, and metolachlor being the most recurrent. In water and sediment, the concentrations of ivermectin (S2A, 1.32 µg/L and 58.18 µg/kg; S2D, 0.8 µg/L and 85.22 µg/kg) and oxytetracycline (S2A, < 1 mg/L and < 1 mg/kg; S2D, 11.8 mg/L and 39 mg/kg) were higher at sites near the establishments. All sites caused between 30 and 38.3% of lethality and produced neurotoxicity and alterations in the reduced glutathione content. Moreover, larvae exposed to samples from all sites incorporated ivermectin. These results demonstrate the degradation of the studied sites in relation to the agricultural activities of the area, highlighting the need to take measures to protect and preserve aquatic ecosystems.


Assuntos
Agricultura , Ecotoxicologia , Monitoramento Ambiental , Poluentes Químicos da Água , Qualidade da Água , Animais , Poluentes Químicos da Água/análise , Argentina , Bovinos , Praguicidas/toxicidade
14.
Sci Total Environ ; 948: 174586, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-38997014

RESUMO

Per- and polyfluoroalkyl substances (PFAS) comprise >4000 synthetic substances used in industrial applications and consumer products. PFAS used daily in households and manufacturing plants end up in domestic sewage, and industrial effluents can be discharged to surface water. Urban watersheds located in low and middle-income countries (LMIC), which lack sanitation infrastructure, are potential recipients of waste containing PFAS. Yet, only a few studies report PFAS occurrence in urban reservoirs and lakes, especially those located in the Global South due to resource limitations. This is the first study aimed to assess PFAS occurrence and ecological risks in Pampulha Lake, Brazil, a site which represents the reality of many other urban watersheds in LMIC as it is surrounded by densely populated areas and manufacturing plants. Surface water samples were collected monthly for 1 year from four sampling points at Pampulha Lake. Sample analysis was based on US Environmental Protection Agency Method 1633, which employs solid phase extraction followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Species sensitivity distribution (SSD) curves were built to identify potentially susceptible species based on detected water concentrations. Bioaccumulation was estimated for fish tissue. Short-chain (perfluorobutanesulfonic acid, PFBS and perfluorohexanoic acid, PFHxA) and long-chain PFAS (perfluorodecanoic acid, PFDA; perfluorooctanoic acid, PFOA; perfluorododecanoic acid, PFDoA; and perfluorooctanesulfonic acid, PFOS) were detected at the µg L-1 range. Total PFAS concentrations in the wet season were generally higher than in the dry season, likely due to limited capacity of the treatment plant processing water from tributaries which receive raw sewage. More than 5 % of aquatic species are potentially susceptible to chronic effects of PFOS at detected concentrations (0.2-2.2 µg L-1). Predicted bioaccumulation of PFOS in fish was above advisory diet intake levels for humans. Results emphasize the need for studies related to PFAS occurrence in watersheds located in LMIC.


Assuntos
Monitoramento Ambiental , Fluorocarbonos , Lagos , Poluentes Químicos da Água , Fluorocarbonos/análise , Brasil , Lagos/química , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , Animais , Caprilatos/análise , Peixes , Medição de Risco
15.
Sci Total Environ ; 948: 174798, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39019288

RESUMO

Cocaine (COC) and benzoylecgonine (BE), the main COC metabolite, have been detected in aquatic ecosystems. Studies focusing on wild fish are, however, very limited, and no reports concerning elasmobranchs are available. This study investigated COC and BE levels in Brazilian Sharpnose sharks (Rhizoprionodon lalandii) (n = 13) using LC-MS/MS. All samples (13/13) tested positive for COC, with 92 % (12/13) testing positive for BE. COC concentrations (23.0 µg kg-1) were over 3-fold higher than BE (7.0 µg kg-1). COC levels were about three-fold significantly higher in muscle (33.8 ± 33.4 g kg-1) compared to liver (12.2 ± 14.2 µg kg-1). Females presented higher COC concentrations in muscle (40.2 ± 35.8 µg kg-1) compared to males (12.4 ± 5.9 µg kg-1). Several positive statistical correlations were noted between COC and BE (rho = 0.84) in females, indicating systemic COC transport and metabolization, as well as between BE and weight (rho = 0.62), and between COC and the Condition Factor (rho = 0.73). A strong correlation was noted between BE and COC in the muscle of non-pregnant females (rho = 1.00). This study represents the first COC and BE report in free-ranging sharks, and the findings point to the potential impacts of the presence of illicit drugs in environments.


Assuntos
Cocaína , Monitoramento Ambiental , Tubarões , Poluentes Químicos da Água , Animais , Cocaína/análogos & derivados , Cocaína/análise , Poluentes Químicos da Água/análise , Brasil , Feminino , Masculino , Monitoramento Ambiental/métodos , Espectrometria de Massas em Tandem
16.
Environ Sci Pollut Res Int ; 31(35): 48674-48686, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39037629

RESUMO

Contamination with traces of pharmaceutical compounds, such as ciprofloxacin, has prompted interest in their removal via low-cost, efficient biomass-based adsorption. In this study, classical models, a mechanistic model, and a neural network model were evaluated for predicting ciprofloxacin breakthrough curves in both laboratory- and pilot scales. For the laboratory-scale (d = 2.2 cm, Co = 5 mg/L, Q = 7 mL/min, T = 18 °C) and pilot-scale (D = 4.4 cm, Co = 5 mg/L, Q = 28 mL/min, T = 18 °C) setups, the experimental adsorption capacities were 2.19 and 2.53 mg/g, respectively. The mechanistic model reproduced the breakthrough data with high accuracy on both scales (R2 > 0.4 and X2 < 0.15), and its fit was higher than conventional analytical models, namely the Clark, Modified Dose-Response, and Bohart-Adams models. The neural network model showed the highest level of agreement between predicted and experimental data with values of R2 = 0.993, X2 = 0.0032 (pilot-scale) and R2 = 0.986, X2 = 0.0022 (laboratory-scale). This study demonstrates that machine learning algorithms exhibit great potential for predicting the liquid adsorption of emerging pollutants in fixed bed.


Assuntos
Celulose , Ciprofloxacina , Aprendizado de Máquina , Redes Neurais de Computação , Ciprofloxacina/química , Adsorção , Celulose/química , Saccharum/química , Poluentes Químicos da Água
17.
Environ Sci Pollut Res Int ; 31(35): 48650-48662, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39037628

RESUMO

The presence of pharmaceuticals in wastewater resulting from human activities has driven researchers to explore effective treatment methods such as adsorption using activated carbon (AC). While AC shows promise as an adsorbent, further studies are essential to comprehend its entire interaction with pharmaceuticals. This article investigates the adsorption of potassium diclofenac (PD) onto AC using experimental and modeling approaches. Batch adsorption studies coupled with Fourier transform infrared spectroscopy (FTIR) were employed to clarify the adsorption mechanism of PD on AC. Various kinetic and isotherm adsorption models were applied to analyze the adsorbent-adsorbate interaction. The kinetics were best described by Avrami's fractional order (AFO) nonlinear model. Also, the intraparticle diffusion (IP) model reveals a three-stage adsorption process. The experimental equilibrium data fitted well with the three-parameter nonlinear Liu model, indicating a maximum adsorption capacity (Qmax) of 88.45 mg g-1 and suggesting monolayer or multilayer adsorption. Thermodynamic analysis showed favorable adsorption (ΔG° < 0), with an enthalpy change (ΔH° = -30.85 kJ mol-1) characteristic of physisorption involving hydrogen bonds and π-π interactions. The adsorption mechanism was attributed to forming a double layer (adsorbate-adsorbent and adsorbate-adsorbate).


Assuntos
Carvão Vegetal , Diclofenaco , Poluentes Químicos da Água , Diclofenaco/química , Adsorção , Carvão Vegetal/química , Poluentes Químicos da Água/química , Cinética , Termodinâmica , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias/química , Carbono/química
18.
Environ Sci Technol ; 58(29): 13087-13098, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38995999

RESUMO

Per- and polyfluoroalkyl substances (PFAS) enter the marine food web, accumulate in organisms, and potentially have adverse effects on predators and consumers of seafood. However, evaluations of PFAS in meso-to-apex predators, like sharks, are scarce. This study investigated PFAS occurrence in five shark species from two marine ecosystems with contrasting relative human population densities, the New York Bight (NYB) and the coastal waters of The Bahamas archipelago. The total detected PFAS (∑PFAS) concentrations in muscle tissue ranged from 1.10 to 58.5 ng g-1 wet weight, and perfluorocarboxylic acids (PFCAs) were dominant. Fewer PFAS were detected in Caribbean reef sharks (Carcharhinus perezi) from The Bahamas, and concentrations of those detected were, on average, ∼79% lower than in the NYB sharks. In the NYB, ∑PFAS concentrations followed: common thresher (Alopias vulpinus) > shortfin mako (Isurus oxyrinchus) > sandbar (Carcharhinus plumbeus) > smooth dogfish (Mustelus canis). PFAS precursors/intermediates, such as 2H,2H,3H,3H-perfluorodecanoic acid and perfluorooctanesulfonamide, were only detected in the NYB sharks, suggesting higher ambient concentrations and diversity of PFAS sources in this region. Ultralong-chain PFAS (C ≥ 10) were positively correlated with nitrogen isotope values (δ15N) and total mercury in some species. Our results provide some of the first baseline information on PFAS concentrations in shark species from the northwest Atlantic Ocean, and correlations between PFAS, stable isotopes, and mercury further contextualize the drivers of PFAS occurrence.


Assuntos
Tubarões , Poluentes Químicos da Água , Animais , Tubarões/metabolismo , Monitoramento Ambiental , Bahamas , Fluorocarbonos/análise , New York , Cadeia Alimentar
19.
Food Res Int ; 191: 114662, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059935

RESUMO

This work explored the impact of ultrasound (US) on the activity, stability, and macrostructural conformation of cyclodextrin glycosyltransferase (CGTase) and how these changes could maximize the production of ß-cyclodextrins (ß-CDs). The results showed that ultrasonic pretreatment (20 kHz and 38 W/L) at pH 6.0 promoted increased enzymatic activity. Specifically, after sonication at 25 °C/30 min, there was a maximum activity increase of 93 % and 68 % when biocatalysis was carried out at 25 and 55 °C, respectively. For activity measured at 80 °C, maximum increase (31 %) was observed after sonication at 25 °C/60 min. Comparatively, US pretreatment at low pH (pH = 4.0) resulted in a lower activity increase (max. 28 %). These activation levels were maintained after 24 h of storage at 8 °C, suggesting that changes on CGTase after ultrasonic pretreatment were not transitory. These pretreatments altered the conformational structure of CGTase, revealed by an up to 11 % increase in intrinsic fluorescence intensity, and resulted in macrostructural modifications, such as a decrease in particle size and polydispersion index (up to 85 % and 45.8 %, respectively). Therefore, the sonication of CGTase under specific conditions of pH, time, and temperature (especially at pH 6.0/ 30 min/ 25 °C) promotes macrostructural changes in CGTase that induce enzyme activation and, consequently, higher production of ß-CDs.


Assuntos
Estabilidade Enzimática , Glucosiltransferases , beta-Ciclodextrinas , Glucosiltransferases/metabolismo , beta-Ciclodextrinas/química , Concentração de Íons de Hidrogênio , Sonicação , Temperatura , Ultrassom
20.
Heliyon ; 10(12): e32894, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38994084

RESUMO

This study investigated the novel application of Fe-TiO2-allophane catalysts with 6.0 % w/w of iron oxide and two TiO2 proportions (10 % and 30 % w/w) for degrading atrazine (ATZ) using the heterogeneous dual-effect (HDE) process under sunlight. Comparative analyses with Fe-allophane and TiO2-allophane catalysts were conducted in both photocatalysis (PC) and HDE processes. FTIR spectra reveal the unique hydrous feldspathoids structure of allophane, showing evidence of new bond formation between Si-O groups of allophane clays and iron hydroxyl species, as well as Si-O-Ti bonds that intensified with higher TiO2 content. The catalysts exhibited an anatase structure. In Fe-TiO2-allophane catalysts, iron oxide was incorporated through the substitution of Ti4+ by Fe3+ in the anatase crystal lattice and precipitation on the surface of allophane clays, forming small iron oxide particles. Allophane clays reduced the agglomeration and particle size of TiO2, resulting in an enhanced specific surface area and pore volume for all catalysts. Iron oxide incorporation decreased the band gap, broadening the photoresponse to visible light. In the PC process, TiO2-allophane achieves 90 % ATZ degradation, attributed to radical species from the UV component of sunlight. In the HDE process, Fe-TiO2-allophane catalysts exhibit synergistic effects, particularly with 30 % w/w TiO2, achieving 100 % ATZ degradation and 85 % COD removal, with shorter reaction time as TiO2 percentage increased. The HDE process was performed under less acidic conditions, achieving complete ATZ degradation after 6 h without iron leaching. Consequently, Fe-TiO2-allophane catalysts are proposed as a promising alternative for degrading emerging pollutants under environmentally friendly conditions.

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