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1.
Braz. j. biol ; 84: e256425, 2024. tab, graf, mapas
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364525

RESUMEN

Using inventory data, this study evaluates the species composition, growing stock volume (GSV), and biomass carbon (BMC) of the five major timber species in the sub-tropical, and temperate/sub-alpine regions of Pakistan. It was found that the stem density varies between 50 and 221 trees ha -1, with a mean of 142 trees ha-1 (13.68 million trees for entire forest area). Among the species, Pinus wallichiana showed a high species composition (27.80%) followed by Picea smithiana (24.64%). The GSV was found in the range of 67.81 to 425.94 m3 ha-1, with a total GSV value of 20.68 million m3 for the entire region. Similarly, The BMC ranged from 27.04 to 169.86 Mg ha-1, with a mean BMC value of 86.80 Mg ha-1. The total amount of stored carbon was found at 8.69 million tons for a total of 95842 ha of commercially managed forest. Furthermore, the correlation analysis between the basal area (BA) and GSV and BMC showed that BA is the best predictor of GSV and BMC. The findings provide insights to the policy makers and forest managers regarding the sustainable commercial forest management as well as forest carbon management in the recent global carbon management for climate change mitigation.


Usando dados de inventário, este estudo avaliou a composição de espécies, volume de estoque crescente (GSV) e carbono de biomassa (BMC) das cinco principais espécies madeireiras nas regiões subtropicais e temperadas/subalpinas do Paquistão. Constatou-se que a densidade do caule variou entre 50 e 221 árvores ha-1, com média de 142 árvores ha-1 (13,68 milhões de árvores para toda a área florestal). Entre as espécies, Pinus wallichiana apresentou alta composição de espécies (27,80%), seguida de Picea smithiana (24,64%). O GSV foi encontrado na faixa de 67,81 a 425,94 m3 ha-1, com um valor total de 20,68 milhões de m3 para toda a região. Da mesma forma, o BMC variou de 27,04 a 169,86 mg ha-1, com valor médio de 86,80 mg ha-1. A quantidade total de carbono armazenado foi de 8,69 milhões de toneladas para um total de 95.842 ha de floresta manejada comercialmente. Além disso, a análise de correlação entre área basal (BA), GSV e BMC mostrou que BA é o melhor preditor de GSV e BMC. As descobertas fornecem insights para os formuladores de políticas e gestores florestais sobre o manejo florestal comercial sustentável, bem como o manejo florestal de carbono no recente gerenciamento global de carbono para a mitigação das mudanças climáticas.


Asunto(s)
Árboles/crecimiento & desarrollo , Carbono , Bosques , Biomasa
2.
Methods Mol Biol ; 2566: 37-43, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36152240

RESUMEN

Lysosomes play key roles in different cellular processes such as autophagy, phagocytosis, and apoptosis. Lysosomal dysfunction is related to many diseases. Fluorescence lysosome staining strategy is valuable for the researches on the lysosome involvement in different pathological diagnosis. Here we describe fluorescence lysosome staining methods with carbon dots for the identification of lysosomes in living and fixed cells.


Asunto(s)
Carbono , Colorantes Fluorescentes , Lisosomas , Microscopía Confocal , Coloración y Etiquetado
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121771, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36027790

RESUMEN

A highly sensitive and selective sensor for the quantitative assay of inorganic pyrophosphatase (PPase) activity was developed based on a fluorescence "turn-off" strategy. Carbon quantum dots@Cu(II)-based metal-organic framework nanotubes (CQDs@Cu-MOF) with length less than 300 nm and width less than 20 nm were synthesized. CQDs in the nanotubes exhibited weak fluorescence owing to static quenching. The coordination reaction between pyrophosphate ion (PPi) and Cu(II) decomposed CQDs@Cu-MOF and led to the release of CQDs, of which the fluorescence recovered. In the presence of PPase, the hydrolysis of PPi generated phosphate ion (Pi). CQDs@Cu-MOF remained their structural stability and the fluorescence turned off. The fluorescence intensity difference of the mixture of CQDs@Cu-MOF and PPi in the absence and presence of PPase (-ΔF) was proportional to the PPase concentration from 0.1 to 5 mU mL-1 and that from 5 to 50 mU mL-1, and a limit of detection at 0.03 mU mL-1 was obtained. PPase activity in human serum was analyzed using the proposed fluorescence sensor and the recovery values were found to vary from 95.0% to 104 %.


Asunto(s)
Estructuras Metalorgánicas , Nanotubos de Carbono , Puntos Cuánticos , Carbono , Difosfatos , Fluorescencia , Humanos , Pirofosfatasa Inorgánica/metabolismo , Pirofosfatasas/química , Pirofosfatasas/metabolismo
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121735, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36049297

RESUMEN

A novel surface enhanced Raman scattering (SERS) method was developed based on Ag nanowires embedded into functionalized metal-organic framework ZIF-67 (ZIF-67@Ag NWs) composite as substrate, which was applied for rapid recognition and sensitive detection of six PAEs. The Raman signals for PAEs detection were gained at ZIF-67@Ag NWs substrate mainly due to the "sharp tip effect" of rough Ag nanowires and excellent absorptive capacity of ZIF-67 to capture targeted molecules into the electromagnetic field. Different structural PAEs, including carbon chain lengths, isomers, and substituents, were evaluated for SERS performance and characteristic peaks under the optimal conditions. The SERS spectra proved that different PAEs exhibited some typically characteristic peaks in favor of recognizing and distinguishing them. The ZIF-67@Ag NWs as SERS substrate was successfully applied to detect six PAEs and exhibited wide linear ranges, low detection limit (LOD), excellent repeatability and stability (such as dibutyl phthalate DBP: linear range of 10-2 âˆ¼ 10-12 mol/L, LOD 3 × 10-13 mol/L). The ZIF-67@Ag NWs substrate by SERS was implemented to determine trace DBP in plastics with satisfactory recoveries of 82.5 % ∼ 108.3 %. The proposed ZIF-67@Ag NWs substrate may provide an effective and promising SERS platform for recognition and quantitative determination of different structural PAEs in environment.


Asunto(s)
Nanopartículas del Metal , Estructuras Metalorgánicas , Nanocables , Carbono , Dibutil Ftalato , Ésteres , Nanopartículas del Metal/química , Ácidos Ftálicos , Plásticos , Plata/química , Espectrometría Raman/métodos
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121770, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36067622

RESUMEN

Quinoline, as a refractory and toxic organic pollutant in coking wastewater, causes great harm to the environment and human health even in trace amount. To realize the selective and sensitive detection of quinoline in coking wastewater, a novel molecularly imprinted fluorescent nanopomegranate with carbon dots (CDs) as seeds and fluorescence source (CD-MIP) was prepared, using quinoline as the template, and N-(ß-aminoethyl)-γ-aminopropyl trimethoxysilane (KH792) as the monomer. The preparation and detection conditions of CD-MIP were systematically optimized. The structure and detection performance of CD-MIP were investigated in detail. The resulting CD-MIP exhibits excellent photoluminescence performance, high detection sensitivity, good selectivity and reproducibility towards quinoline. Under the optimized conditions, the fluorescence intensity of CD-MIP shows a satisfying linearity with quinoline concentration in the range of 20-200 mg/L with a detection limit of 6.7 mg/L. Owing to the existence of imprinted cavities that highly match with quinoline, a high imprinting factor (3.46) for CD-MIP was obtained. In addition, CD-MIP represents a greater affinity towards quinoline than towards other analogues, as well as an outstanding anti-interference capability. For trace analysis in real coking wastewater, CD-MIP also gives satisfactory results. Therefore, CD-MIP shows promising application in the selective detection of trace quinoline in wastewater.


Asunto(s)
Coque , Contaminantes Ambientales , Impresión Molecular , Puntos Cuánticos , Quinolinas , Carbono/química , Humanos , Límite de Detección , Impresión Molecular/métodos , Puntos Cuánticos/química , Reproducibilidad de los Resultados , Aguas Residuales
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121774, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36081194

RESUMEN

In the realm of dye sensitized solar cells (DSSCs), the 3d transition metals as photosensitizers are scarcely studied. In the present work, electronic structures, FMO, MEP surfaces, NBO analysis, energetics and photophysical properties of earth abundant metals (Mn, Fe and Co) based metalloporphyrins coordinated with NHC-carbene have been explored by using DFT and TDDFT calculations. According to formation energies and energy decomposition analysis (EDA), the cobalt based metalloporphyrins species are found to be more stable while in contrast manganese based species are predicted as more reactive among all. Also, from the ligation point of view, the TPP (meso-tetraphenylporphyrin) ligand forms more steady and rigid coordination as compare to the TTP (meso-tetratolylporphyrin) ligand. FMO analysis also support these observations. NBO and SNO results support the electronic configurations as well as unveil the controversial bonding pattern of NHCcarbon and metal atom and found that there is σ-bonding present between the metal and the NHCcarbon by the overlapping of sp-hybridized orbitals of carbenecarbon and sp/d hybrid orbital of the metal atom. TDDFT results show that the highest light harvesting efficiency (LHE) of all the studied species is found under the range of 360 nm - 380 nm (λ) and this may due to the presence of longer π-conjugations. In-depth investigation of this work may help to design new robust energy harvesting systems for high energy conversion efficiency based on earth abundance metals. Our results are in well agreement with the available experimental findings.


Asunto(s)
Metaloporfirinas , Porfirinas , Carbono , Cobalto , Electrónica , Ligandos , Manganeso , Metaloporfirinas/química , Metales , Metano/análogos & derivados , Modelos Teóricos , Fármacos Fotosensibilizantes , Porfirinas/química
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121756, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36088740

RESUMEN

The growing appearance of antibiotic-resistant strains of microorganisms originated from the widespread use and ubiquitous presence of such drugs is a major concern in the world. The development of methodologies able to detect such substances at low concentration in real water samples is mandatory to overcome this problem. Europium(III) is known to form complexes with tetracycline (TC) with photoluminescent characteristics useful for TC determination. In the present work, we synthesized for the first time carbon nanoparticles (CN) showing delayed photoluminescence using a Europium(III) doping synthesis. The new material (PCNEu) was characterized both morphologically and spectroscopically, showing an analytical photoluminescent signal in presence of TC, arising from the 5D0→7F2 transition of europium, one hundred times higher than that of the europium salt alone in presence of the antibiotic. This enhancement is a consequence of the amplifying effect exerted by nanoparticle structure itself, leading to an efficient synergistic "antenna effect" in the system PCNEu - TC. The analytical signal is affected both by pH and the nature of the buffer used, and it allows the detection of tetracycline in waters with a limit of detection of 2.18 nM and recoveries between 90 and 110%. The analytical performance of the developed methodology enables having lower limits of detection than other luminescent and chemiluminescent reported methodologies.


Asunto(s)
Compuestos Heterocíclicos , Nanopartículas , Antibacterianos/química , Carbono/química , Europio/química , Indicadores y Reactivos , Nanopartículas/química , Tetraciclina/química , Agua
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121832, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36088741

RESUMEN

Total antioxidant capacity (TAC) is an important indicator for evaluating oxidative stress of the human body. Since TAC is related to the concentration of reducing substances, it can be detected by using peroxidase-like or oxidase-like activity of nanozyme materials. In this work, the cobalt and nitrogen co-doped carbon dots (Co/N-CDs) are fabricated for building stability and high peroxidase-like nanozyme through the Box-Behnken design of response surface methodology. The morphology and luminescence properties of obtained Co/N-CDs were characterized by TEM and fluorophotometer, respectively. Interestingly, the surface charge of Co/N-CDs are innovatively investigated by a simple and widespread gel electrophoresis, which holds the potential to be an alternative to Zeta potential analysis. In addition, a flow injection spectrophotometric assay to detect ascorbic acid is develop with a high sensitivity and automation based on a Co/N-CDs/guaiacol/H2O2 catalytic reaction system. The proposed method is also responsive to other reducing substances such as cysteine and glutathione. Therefore, the presented sensor can realize the determination of TAC, and then, some actual human serum samples are detected accurately and quickly (the recovery rates are 93.46-105.61 %).


Asunto(s)
Carbono , Puntos Cuánticos , Antioxidantes/análisis , Ácido Ascórbico , Cobalto , Cisteína/análisis , Glutatión , Guayacol , Humanos , Peróxido de Hidrógeno/análisis , Nitrógeno , Peroxidasa , Peroxidasas
9.
Food Chem ; 400: 134074, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36088889

RESUMEN

Allergies are defined as a hypersensitivity reaction, immunologically mediated, as a result to an external stimulus. Peanuts induced allergies are considered one of the most severe, life-threatening food sensitivities since they trigger the highest frequency of severe and fatal reactions, even in trace amounts. Therefore, it is imperative to develop fast, accurate and easy-to-use analytical methods to determine Ara h1, is a seed storage protein from Arachis hypogea and the main peanut derived allergen. In this work, two strategies were applied to develop an electrochemical aptasensor based on GO-COOH and metallic nanoparticles immobilised on screen-printed carbon electrodes (SPCEs). The analytical performances of the aptasensor showed a linear range of 5-150 nM, and a limit of detection of 1.66 nM. The method was applied in peanut-free food samples with very good recoveries proving to be a promising tool for peanut allergy prevention.


Asunto(s)
Arachis , Hipersensibilidad al Cacahuete , Alérgenos , Antígenos de Plantas , Carbono , Proteínas de Plantas , Proteínas de Almacenamiento de Semillas
10.
Food Chem ; 398: 133822, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35961169

RESUMEN

A portable device is conducive to the on-site detection of heavy metal ions at trace level in food and the prevention of related food safety issues. In this work, an electrochemical device stacked up with flat electrodes was developed for the detection of Pb2+ and Cd2+. The top layer of the device is a carbon paper as working electrode, which is modified with amino functionalized cobalt-based metal-organic framework and gold nanoparticles. The bottom layer was constructed with the carbon counter electrode and Ag/AgCl reference electrode, and a punched sample cell (Φ = 8 mm) was in the middle. The proposed method could simultaneously determinate Pb2+ and Cd2+ via anodic stripping voltammetry with the detection limit of 7.0 × 10-2 ng mL-1 and 1.1 × 10-2 ng mL-1, and was applied in real food samples (drinking water, juice, tea, grain, fruits, vegetables, liver and aquatic products) with the recovery of 91.2-105.4 % and 90.2-111.2 %, respectively.


Asunto(s)
Nanopartículas del Metal , Estructuras Metalorgánicas , Cadmio , Carbono , Electrodos , Oro , Iones , Plomo
11.
Food Chem ; 398: 133935, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35986995

RESUMEN

Nitrite is a widely used food additive that has been shown to be carcinogenic and can cause health damage when consumed in excess. Therefore, developing a detection method is in demand. Here, we prepared a novel Fe-doped carbon dots (Fe-CDs) using metallic deep eutectic solvent (MDES) which showed high sensitivity and selectivity. Besides, it also showed excellent pH-dependent luminescence characteristics, which proved the feasibility as a pH sensor. Under the optimal conditions, the detection linear of nitrite ranged from 0.2 to 80 µM, and the detection limit was 50 nM. The recovery rate was between 98.8 % and 104.1 % in food and water samples. For pH monitoring, its fluorescence intensity was linearly correlated in the pH range from 2 to 7, accompanying a unique differential solution color change of colorless-yellow-green. Therefore, it can be used as an excellent fluorescent probe for detection of nitrite and pH in food and water environment.


Asunto(s)
Colorantes Fluorescentes , Puntos Cuánticos , Carbono , Disolventes Eutécticos Profundos , Concentración de Iones de Hidrógeno , Nitritos , Solventes , Agua
12.
Methods Mol Biol ; 2565: 105-112, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36205890

RESUMEN

Amperometry is an electrochemical method based on the oxidation or reduction of molecules. Many secretion products, including catecholamines, contain in their molecule chemical groups with the ability to yield (oxidize) or capture (reduce) electrons upon its exposure to an electrical field. In order to measure the secretion of catecholamines, they are oxidized at +650 mV with a carbon electrode, releasing every molecule of catecholamine that is oxidized two electrons (e-) that are recorded as an electrical current. Amperometry is an easy-to-use and noninvasive technique for cells (unlike patch-clamp techniques for measuring membrane capacitance) and has been widely used to monitor online catecholamine release from perifused bovine chromaffin cell populations.


Asunto(s)
Células Cromafines , Animales , Carbono , Catecolaminas , Bovinos , Electrodos , Técnicas de Placa-Clamp
13.
Food Chem ; 399: 133970, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35998499

RESUMEN

Lateral flow immunoassays (LFIAs) are routine methods for rapid foodborne pollutants screening, with detection limits that are closely associated with the label probes used. The exploitation of high performance and robust probe is highly desirable, and remains a great challenge. Herein, we reported an emerging fluorescent nanobeads i.e. carbon-dots (CD) covalently incorporated mesoporous silicon nanoparticles (CD-MSNs) for LFIAs. CD-MSNs revealed brighter fluorescence, larger particle size and more modification sites in comparison with those of single CD. After bio-functionalisation, CD-MSNs probes were introduced to construct LFIA test strips, and designed for ultrasensitive detection of aflatoxin B1 (AFB1) and Staphylococcus aureus (S. aureus), two representative foodborne pollutants, based on the competitive and sandwich models, respectively. Very competitive quantitative detection limits i.e. 0.05 ng/mL and 102 cfu/mL were correspondingly obtained. Additionally, the test strips were successfully applied to rapidly and accurately screen AFB1 and S. aureus in food samples, highlighting their practicality.


Asunto(s)
Contaminantes Ambientales , Nanopartículas , Aflatoxina B1/análisis , Carbono , Colorantes Fluorescentes , Inmunoensayo/métodos , Límite de Detección , Silicio , Staphylococcus aureus
14.
J Hazard Mater ; 441: 129881, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36063710

RESUMEN

Microplastics (MPs) are frequently detected in urban waters, which would pose a threat to human health through the food chain. Thus, efficient approaches to the elimination of MPs are urgently required. Pyrolysis is a powerful technique for the potential treatment of MPs. The online thermogravimetry-Fourier transform infrared reflection-Mass spectrometry (TG-FTIR-MS) is applied for tracking the pyrolysis process of representative polyethylene (PE) and polyvinyl chloride (PVC) MPs in urban waters, together with or without the FeAlOx catalyst. TG could quantitatively determine the decomposition behavior and kinetics of MPs while FTIR and MS spectra would be capable of characterizing the pyrolysis products. The results revealed that FeAlOx is an excellent carbon support, and the deposited carbon can be gasified to CO at higher pyrolysis temperatures. Moreover, more aromatic compounds were generated from the pyrolysis of PE MPs with the catalyzation of FeAlOx. Large quantities of benzene were also produced in the PVC MPs pyrolysis with or without FeAlOx. Also, FeAlOx largely decreased the concentrations of chlorine-containing compounds in the liquid products of PVC MPs pyrolysis. This study provides a efficient technique for the online observation of the MPs' catalytic pyrolysis process, which would guide future upcycling of MPs into value-added products.


Asunto(s)
Microplásticos , Cloruro de Polivinilo , Benceno , Carbono , Cloro , Humanos , Plásticos , Polietileno/química , Pirólisis , Espectroscopía Infrarroja por Transformada de Fourier
15.
J Hazard Mater ; 441: 129846, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36063712

RESUMEN

Exhaust emissions from gasoline vehicles are one of the major contributors to aerosol particles observed in urban areas. It is well-known that these tiny particles are associated with air pollution, climate forcing, and adverse health effects. However, their toxicity and bioreactivity after atmospheric ageing are less constrained. The aim of the present study was to investigate the chemical and toxicological properties of fresh and aged particulate matter samples derived from gasoline exhaust emissions. Chemical analyses showed that both fresh and aged PM samples were rich in organic carbon, and the dominating chemical species were n-alkane and polycyclic aromatic hydrocarbons. Comparisons between fresh and aged samples revealed that the latter contained larger amounts of oxygenated compounds. In most cases, the bioreactivity induced by the aged PM samples was significantly higher than that induced by the fresh samples. Moderate to weak correlations were identified between chemical species and the levels of biomarkers in the fresh and aged PM samples. The results of the stepwise regression analysis suggested that n-alkane and alkenoic acid were major contributors to the increase in lactate dehydrogenase (LDH) levels in the fresh samples, while polycyclic aromatic hydrocarbons (PAHs) and monocarboxylic acid were the main factors responsible for such increase in the aged samples.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Alcanos/análisis , Carbono/análisis , Gasolina/análisis , Gasolina/toxicidad , Hong Kong , Lactato Deshidrogenasas/análisis , Material Particulado/análisis , Material Particulado/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Emisiones de Vehículos/análisis , Emisiones de Vehículos/toxicidad
16.
J Hazard Mater ; 441: 129871, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36067561

RESUMEN

Highly efficient single atom catalysts are critical to substantially promote for peroxymonosulfate (PMS) activation to organic pollutant degradation, but it remains a challenge at present. Herein, single atom Mn anchored on N-doped porous carbon (SA-Mn-NSC) was synthesized by ball milling of Mn-doped carbon nitride and spirulina biochar to dominantly activate PMS. The precursor of carbon nitride and spirulina possessed a strong coordinating capability for Mn(II), facilitating the formation of highly dispersed nitrogen-coordinated Mn sites (Mn-N4). The SA-Mn-NSC catalyst exhibited high activity and stability in the heterogeneous activation of PMS to degrade a wide range of pollutants within 10 min, showing an outstanding degradation rate constant of 0.31 min-1 in enrofloxacin (ENR) degradation. The high surface density of Mn-N4 sites and abundant interconnected meso-macro pores were highly favorable for activating PMS to produce 1O2 and high-valent manganese (Mn(IV)) for pollutant degradation. This work offers a new pathway of using a low-cost and easily accessible single-atom catalysts (SACs) and could inspire more catalytic oxidation strategies.


Asunto(s)
Contaminantes Ambientales , Spirulina , Carbono , Catálisis , Enrofloxacina , Manganeso , Nitrilos , Nitrógeno , Peróxidos , Porosidad
17.
J Hazard Mater ; 441: 129879, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36084464

RESUMEN

Rivers play a critical role in the global carbon cycle, but the processes can be affected by widespread microplastic (MP) pollution and the increasing frequency of heat waves (HWs) in a warming climate. However, little is known about the role of river microbes in regulating the carbon cycle under the combined action of MP pollution and HWs. Here, through seven-day MP exposure and three cycles of HW simulation experiments, we found that MPs inhibited the thermal adaptation of the microbial community, thus regulating carbon metabolism. The CO2 release level increased, while the carbon degradation ability and the preference for stable carbon were inhibited. Metabonomic, 16 S rRNA and ITS gene analyses further revealed that the regulation of carbon metabolism was closely related to the microbial r-/K- strategy, community assembly and transformation of keystone taxa. The random forest model revealed that dissolved oxygen and ammonia-nitrogen were important variables influencing microbial carbon metabolism. The above findings regarding microbe-mediated carbon metabolism provide insights into the effect of climate-related HWs on the ecological risks of MPs.


Asunto(s)
Microplásticos , Ríos , Amoníaco , Carbono , Dióxido de Carbono , Calor , Microplásticos/toxicidad , Nitrógeno , Oxígeno , Plásticos
18.
J Hazard Mater ; 441: 129792, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36084470

RESUMEN

Cooking Oil Fumes (COFs) contain carcinogenic organic substances such as polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs), of which 2-Amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP) is known as mainly meat-borne carcinogens. In this work, to identify the mechanisms to induce the inflammation response in human lung cells (A549) exposed to COFs, we investigated the physicochemical and biological characteristics of COFs generated with PhIP precursors (L-phenylalanine, creatinine, and glucose) at high cooking temperatures (300 °C and 600 °C). Interestingly, we found that PhIP was not formed both at 300 °C and 600 °C, while a large number of carbon nanoparticles were generated from soybean oil containing the PhIP precursors at 600 °C. From the biological analysis, COFs generated with the PhIP precursors at 600 °C induced the most significant pro-inflammatory cytokine (IL-6). This result indicates that the particulate matter in COFs generated with the PhIP precursors above the smoke temperature is the primary factor directly affecting the lung inflammatory response rather than PhIP. This study demonstrates for the first time a novel principle of the inflammatory response that the PhIP precursors can aggravate lung injury by affecting the physical properties of COFs depending on cooking temperature. Therefore, our finding is a significant result of overcoming the bias in previous studies focusing only on the chemical toxicity of PhIP in the inflammatory response of COFs.


Asunto(s)
Material Particulado , Hidrocarburos Policíclicos Aromáticos , Aminas/análisis , Carbono/análisis , Carcinógenos/análisis , Culinaria , Creatinina/análisis , Glucosa , Humanos , Inflamación/inducido químicamente , Interleucina-6 , Pulmón , Carne/análisis , Material Particulado/análisis , Material Particulado/toxicidad , Fenilalanina , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Humo/análisis , Aceite de Soja/análisis , Temperatura
19.
J Hazard Mater ; 441: 129824, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36087529

RESUMEN

The aerobic, lincomycin-degrading bacterial strain Conexibacter sp. LD01, belonging to the phylum Actinobacteria, was isolated from activated sludge. Both second- and third-generation sequencing technologies were applied to uncover the genomic characterization and high-quality genome with 99.2% completeness and 2.2% contamination was obtained. The biodegradation kinetics of lincomycin fit well with the modified Gompertz model (R2 > 0.97). Conexibacter sp. LD01 could subsist with lincomycin as the sole source of carbon, nitrogen, and energy. When 500 mg/L of glucose was added as a co-substrate, the biodegradation rate improved significantly, whereas the addition of 500 mg/L sodium pyruvate had a slight inhibitory effect. Ammonia nitrogen was the best nitrogen source for Conexibacter sp. LD01 when growing and degrading lincomycin. In total, 17 metabolic products consisting of nine novel products were detected, and five biodegradation pathways, including N-demethylation, breakage of the amido bond, sulfoxidation, and oxidation of the pyrrolidine ring and propylamino chain, were proposed. This study significantly expands our understanding of the functional microorganisms and mechanism involved in lincomycin biodegradation at the phylum level.


Asunto(s)
Lincomicina , Aguas del Alcantarillado , Amoníaco/metabolismo , Bacterias/metabolismo , Biodegradación Ambiental , Carbono/metabolismo , Genómica , Glucosa/metabolismo , Cinética , Nitrógeno/metabolismo , Piruvatos , Aguas del Alcantarillado/química , Sodio
20.
J Hazard Mater ; 441: 129919, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36099738

RESUMEN

Methylmercury (MeHg+) is one of the common organic species of mercury, and has much higher toxicity than inorganic mercury. Based on the selective enhancement of the activity of nanozyme (NA-CDs/AuNPs) by MeHg+, a novel colorimetric nanoprobe for MeHg+ assay is proposed. The noradrenaline-based carbon dots (NA-CDs) as the reducing agent was applied to prepare the NA-CDs/AuNPs. The formation of gold amalgamation (Au@HgNPs) between nanozyme and MeHg+ allows to simultaneously accelerate the electron transfer from Au and Hg to NA-CDs and the generation of radicals (i.e. ∙OH, ∙O2- and ∙CH3). The NA-CDs/AuNPs has an outstanding anti-interference performance even in the presence of different mercury. Further density functionality theory (DFT) calculations revealed that the formation of Au@HgNPs via MeHg+ contributes to the significantly lowered activation energy, resulting in the peroxidase-like activity generation and acceleration. This leads to rapid (10 min) and specific colorimetric detection of MeHg+ with the detection limit of 0.06 µg L-1. This introduces a novel method for simple and sensitive detection of MeHg+, giving a new horizon for the assay of organometallic compounds.


Asunto(s)
Mercurio , Nanopartículas del Metal , Compuestos de Metilmercurio , Carbono , Colorimetría/métodos , Oro , Norepinefrina , Peroxidasas , Sustancias Reductoras
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