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1.
Sci Total Environ ; 906: 167491, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37778559

RESUMO

The ongoing degradation of seagrass and seaweed is of global concern. Comprehending the spatial distribution of these wetland vegetation types and the threats they face becomes critical for effective conservation and restoration efforts. In this study, we combined a species distribution model and geographical detector to propose a novel framework for mapping the distribution and disturbance of degraded coastal wetland vegetation in sparsely recorded areas and identifying conservation and restoration priorities. Guangxi is a province in China known for its extensive coastal wetland vegetation. In our study of Guangxi, habitats suitable for two degraded vegetation types, i.e., seagrass and seaweed, were mapped using the maximum entropy model; 669.44 km2 of seagrass habitat and 929.69 km2 of seaweed habitat were identified. The geographical detector model was used to analyze anthropogenic disturbance caused by four local disturbance factors: shoreline development, fisheries, waterways, and ports and anchorages. Shoreline development was identified as the disturbance factor with the strongest impact on potential habitats of both vegetation types. According to these findings, 48.40 %-64.23 % of the vegetation habitats suffered from high anthropogenic disturbance. Preexisting nature reserves had not effectively protected wetland vegetation from human disturbance. Based on the spatial pattern of vegetation habitat and comprehensive anthropogenic disturbance, conservation and restoration priorities for seagrasses and seaweeds covering an area of 302.26 km2 were further mapped. Our results thus help improve wetland vegetation conservation by providing basic information, and they provide a tool to support site planning for seagrass and seaweed conservation and restoration.


Assuntos
Alga Marinha , Áreas Alagadas , Humanos , China , Ecossistema , Verduras , Conservação dos Recursos Naturais
2.
Sci Total Environ ; 906: 167466, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37788779

RESUMO

In alpine grasslands, increased N deposition is increasing the dominance of grasses relative to other functional types according to our previous study Shen et al. (2022). However, the mechanisms that drive this compositional change are not fully understood. We measured the effects of 4-6 years' N addition to simulate N deposition at rates of 0 (CK), 8 (N1), 24 (N2), 40 (N3), 56 (N4), and 72 (N5) kg N ha-1 year-1 on dominant representatives of four functional types, Leymus secalinus (grass), Carex capillifolia (sedge), Potentilla multifidi (non-leguminous forb), and Medicago ruthenica (legume), in the alpine grassland on the Qinghai-Tibetan Plateau (QTP). In-situ experiment showed that N addition increased aboveground biomass in L. secalinus but had negative or neutral effects on aboveground biomass in the other species. Consistent with this finding, N addition increased net photosynthesis, chlorophyll content, and rubisco activity in L. secalinus with less positive effects on the other species. Nitrogen addition increased leaf N content in L. secalinus and C. capillifolia and reduced leaf non-structural carbohydrate content in all four species. In L. secalinus, the highest N addition rate (N5) reduced MDA content, a marker of oxidative stress, by enhancing antioxidant enzyme activity. Overall, our findings suggested that physiological factors can contribute to increased competitiveness of grass relative to sedge, forb and legume species under high N application levels. The rapid growth of this grass species reduces resource availability to non-grass species, increasing its dominance in the alpine meadow.


Assuntos
Pradaria , Poaceae , Poaceae/fisiologia , Solo/química , Biomassa , Verduras , Medicago
3.
Sci Total Environ ; 906: 167619, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37806594

RESUMO

Microplastics (MPs) and antibiotic resistance genes (ARGs) are both enriched in soil-vegetable systems as a consequence of the prolonged use of agricultural mulches. MPs can form unique bacterial communities and provide potential hosts for ARGs. Therefore, MPs stress may promote the spread of ARGs from soil to crops. Increasing ARGs pollution in soil-vegetable system. In our research, we investigated the distribution and major driving elements of antibiotic resistance genes in the soil-vegetable system under microplastic stress. The results showed that MPs treatment decreased the relative abundance of ARGs in non-rhizosphere soil. High concentrations of MPs promoted the enrichment of tetracycline antibiotic resistance genes in rhizosphere soil. MPs treatment promoted the enrichment of ARGs and mobile genetic elements (MGEs) in lettuce tissues, and the overall abundance of ARGs in root after 0.5 %, 1 %, and 2 % (w/w, dry weight) polyethylene (PE) administration was considerably higher compared to that in the untreated group (p < 0.05). At the same time, high PE concentrations promoted the spread of sulfa ARGs from root to leaf. MPs also impacted the bacterial communities in the soil-plant system, and the changes in ARGs as well as MGEs in each part of the soil-vegetable system were significantly correlated with the bacterial diversity index (p < 0.05). Correlation analysis and network analysis showed that bacterial communities and MGEs were the main drivers of ARGs variation in soil-lettuce systems.


Assuntos
Microplásticos , Verduras , Genes Bacterianos , Solo , Plásticos , Antibacterianos/farmacologia , Microbiologia do Solo , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Alface , Polietilenos
4.
Food Chem ; 434: 137482, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37722339

RESUMO

A novel biomimetic mineralized covalent organic framework (BM-COF) was prepared based on magnetic silk fibroin and a new sulforaphane pretreatment technology was constructed. First, metal coordination was performed on the surface of silk fibroin, and nanoparticles were deposited by in-situ mineralization after co-precipitation. Then, biomineralized COFs were prepared by in-situ self-assembly of a COF layer on Fe3O4@silk fibroin surface guided by interfacial directional growth technology. The BM-COFs had a multilayer structure, large specific surface area and pore volume, and superparamagnetic properties, which make them an ideal adsorbent. The adsorption of sulforaphane by BM-COFs is mainly multi-molecular layer adsorption and chemisorption, there might be electrostatic action, π-stacking and hydrogen bonding in the adsorption process. The composite material was successfully used for the pretreatment of sulforaphane in cruciferous vegetables. An extraction time of 30 min gave extraction efficiencies as high as 92%, and the recovery could reach more than 73%.


Assuntos
Fibroínas , Fibroínas/química , Verduras , Biomimética , Adsorção , Fenômenos Magnéticos , Extração em Fase Sólida
5.
Food Chem ; 434: 137469, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37729780

RESUMO

This article reviewed the latest research progress of Surface-enhanced Raman Spectroscopy (SERS) in the security detection of fruits and vegetables in recent years, especially in three aspects: pesticide residues, microbial toxin contamination and harmful microorganism infection. The binding mechanism and application potential of SERS detection materials (including universal type and special type) and carrier materials (namely rigid and flexible materials) were discussed. Finally, the application prospect of SERS in fruit and vegetable safety detection was explored, and the problems to be solved and development trends were put forward. The poor stability and reproducibility of SERS substrates make it difficult for practical applications. It is necessary to continuously optimize SERS substrates and develop small and portable Raman spectroscopy analyzers. In the future, SERS technology is expected to play an important role in human health, food safety and economy.


Assuntos
Resíduos de Praguicidas , Análise Espectral Raman , Humanos , Análise Espectral Raman/métodos , Frutas/química , Verduras/química , Reprodutibilidade dos Testes , Resíduos de Praguicidas/análise
6.
Gene ; 891: 147799, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37739194

RESUMO

The insecticide dimethoate, an organophosphate, has been used on crops, soybeans, fruits, and vegetables since the 1960s and is considered one of the most widely used pesticides. However, the understanding of the molecular mechanisms of dimethoate in crops, especially crop seedlings, is still limited. The green vegetable soya bean (Glycine max merr) is usually used as a vegetable-like fruit of soybean in many Asian countries. This study aimed to analyze the effect of dimethoate on the growth of green vegetable soya bean seedlings at the metabolic and transcriptional levels. An integrated analysis of the transcriptome and metabolome was performed to determine the responses of green vegetable soya bean seedlings to different concentrations (D1 for low dose, D2 for high dose and C for control) of dimethoate. In omics analyses, 4156 differentially expressed genes (DEGs) and 1935 differentially abundant metabolites (DAMs) were identified in the D1/C comparison, and 11,162 DEGs and 819 DAMs were identified in D2/C. Correlation analyses revealed dimethoate affected the metabolic pathways of green vegetable soya beans such as the biosynthesis of secondary metabolites and microbial metabolism in diverse environmental pathways, demonstrating that even small doses of dimethoate can affect green vegetable soya bean seedlings in a short period of time. Our study further enriches our understanding of the molecular mechanisms by which green vegetable soya beans are treated with dimethoate and provides a deeper understanding of the effects of dimethoate on crops.


Assuntos
Soja , Verduras , Soja/genética , Verduras/genética , Dimetoato/toxicidade , Dimetoato/metabolismo , Transcriptoma , Plântula/genética , Plântula/metabolismo
7.
Food Chem ; 432: 137221, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37633146

RESUMO

In the booming global population, monitoring of mesotrione (MTN) like agricultural pollutants is crucial for human safety. Herein, the research reports the synthesis of tungsten trioxide (WO3) and cobalt oxide (Co3O4) nanostructures intercalated ball milling exfoliated graphene (WO3/Co3O4/graphene) 3D helix electrocatalyst for the electrochemical detection of MTN herbicide. The proposed WO3/Co3O4/graphene sensor material achieved a wide range of MTN detection from 0.001 µM to 1885 µM. In addition, the estimated limit of sensing and sensitivity values are 0.42 nM and 0.802 µAµM-1 cm-2 respectively. The real sample experiment was accomplished in MTN-added vegetables (corn, sugar cane, tomato, green soybean) and environmental samples (sewage water, river water). At most, the recorded minimum MTN response recovery in vegetables and water samples is about 95% and 98% respectively. Furthermore, the designed sensor electrode achieved storage stability of 98.7% after three weeks.


Assuntos
Grafite , Herbicidas , Humanos , Verduras
8.
Food Chem ; 432: 137293, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37657342

RESUMO

Glycidyl fatty acid esters (GEs) have been identified as food contaminants that can form during the processing and heating of edible oils. Their widespread occurrence raises potential concerns for consumers. This study aimed to develop a simple and effective analytical method for molecular recognition using mass spectrometry fragmentation patterns. Furthermore, it sought to simultaneously and quantitatively determine five common GEs in highly complex fatty matrices (oils) using high-performance liquid chromatography-triple quadrupole tandem mass spectrometry (HPLC-ESI-QQQ-MS/MS). An extraction method using acetonitrile was used, and the purification of the extract was optimized using cryo-degreasing-tandem dispersive solid-phase extraction (d-SPE) to eliminate fatty interferents. The method validation yielded recoveries ranging from 81.17% to 109.28% and the method precision was < 10.00%. The limits of quantification ranged from 0.08 to 0.21 ng/g, which is below the current legal limits. This approach may play a crucial role in ensuring food safety.


Assuntos
Espectrometria de Massas em Tandem , Verduras , Óleos de Plantas , Cromatografia Líquida de Alta Pressão , Ácidos Graxos , Extração em Fase Sólida , Ésteres
9.
Food Chem ; 436: 137747, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37862985

RESUMO

The current study synthesized a molecularly imprinted polymer, combined it with the QuEChERS method to form a new hybrid technique, the QuEChERS-MISPE as an alternative to the QuEChERS-dSPE for analysis of DDTs as model pesticides. Batch studies confirmed that the binding of the DDTs to the MIP cavities formed a monolayer formation through chemisorption resulting in an adsorption capacity of 429 ng g-1. A study of matrix effects indicated signal suppression for both techniques. However, the new QuEChERS-MISPE technique is less affected by matrix effects, has better sensitivity and recoveries compared to the conventional QuEChERS-dSPE technique. Application of the new QuEChERS-MISPE technique detected trace levels of DDTs in vegetables in South Africa. However, a health risk assessment indicated that potential risks for consumers was minimal. Although the risk is minimal, the detection of DDTs in vegetables in South Africa should be a concern and more constant monitoring is required.


Assuntos
Impressão Molecular , Praguicidas , Verduras , DDT , Extração em Fase Sólida/métodos , África do Sul
10.
Food Chem ; 430: 137007, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37536071

RESUMO

A novel fluorescence "off-on-off" probe was presented to detect Zn(II) and oxalic acid (OA) based on nitrogen-doped MXene quantum dots (N-MQDs), which were synthesized by an ultrasound approach at room temperature with nitric acid and ethylenediamine. These N-MQDs displayed small size (<10 nm), water dispersibility, and good photoluminescence. Furthermore, the N-MQDs showed an selective response towards Zn(II) through fluorescence enhancement, with a limit of detection (LOD) calculated as 0.127 µM in the linear range of 0-20 µM. Then, the fluorescence of N-MQDs/Zn(II) system could be selectively quenched after adding OA, with an effective response in the range from 0 to 20 µM (LOD: 0.883 µM). The fluorescence "turn-on" and "turn-off" properties of N-MQDs were resulted from the intramolecular charge transfer (ICT) of Zn(II) and the coordination between OA and Zn(II), respectively. This sensing platform was successfully applied for Zn(II) and OA detection in actual environmental and vegetable samples.


Assuntos
Pontos Quânticos , Água , Verduras , Ácido Oxálico , Nitrogênio , Ultrassom , Corantes Fluorescentes , Espectrometria de Fluorescência , Zinco , Carbono
11.
Food Chem ; 430: 137064, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549619

RESUMO

An in vivo solid-phase microextraction (SPME) fiber with high-coverage capture capacity of plant endogenous substances based on the porous covalent triazine framework (CTF) material was developed. The CTF fiber coupled with gas chromatographic quadrupole time-of-flight mass spectrometer (GC-QTOF-MS) analysis was used for monitoring untargeted endogenous metabolites in living Chinese cabbage plants (Brassica campestris L. ssp. chinensis Makino (var. communis Tsen et Lee)). A total of 100 endogenous substances were identified, mainly including aldehydes, ketones, acids, alcohols, phenols, alkanes, alkenes, esters, isorhodanates, nitriles, as well as indole and its derivatives. Using the in vivo metabolites analysis method, Chinese cabbage plants at different growing stages demonstrated significantly statistical differences in plant metabolism. In addition, metabolic dysregulation of Chinese cabbage plants under fipronil pesticide contamination was observed. To summarize, the proposed approach provides a feasible method to capture metabolic information in living vegetables and for risk assessment of pesticide use during agricultural production.


Assuntos
Brassica , Compostos Orgânicos Voláteis , Verduras , Microextração em Fase Sólida/métodos , Álcoois/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa , Compostos Orgânicos Voláteis/análise
12.
Food Chem ; 431: 137067, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37579609

RESUMO

A novel dual-signal fluorescent sensor was developed for detecting organophosphorus pesticides (OPs). It relies on the catalytic activities of acetylcholinesterase (AChE) and choline oxidase (ChOx) to generate hydrogen peroxide (H2O2) through the conversion of acetylcholine (ACh) to choline·H2O2 then oxidizes ferrocene-modified tetraphenylethylene (TPE-Fc) to its oxidized state (TPE-Fc+), resulting in enhanced cyan fluorescence due to aggregation. Simultaneously, ferrocene oxidation generates hydroxyl radicals (•OH), causing a decrease in orange fluorescence of glutathione-synthesized gold nanoclusters (GSH-AuNCs). The presence of OPs restricts AChE activity, reducing H2O2 production. Increasing OPs concentration leads to decreased cyan fluorescence and increased orange fluorescence, enabling visual OPs detection. The sensor has a linear dynamic range of 10-2000 ng/mL with a detection limit of 2.05 ng/mL. Smartphone-based color identification and a WeChat mini program were utilized for rapid OPs analysis with successful outcomes.


Assuntos
Técnicas Biossensoriais , Resíduos de Praguicidas , Praguicidas , Resíduos de Praguicidas/análise , Acetilcolinesterase/química , Praguicidas/análise , Compostos Organofosforados/análise , Verduras , Metalocenos , Peróxido de Hidrogênio/química , Corantes/análise , Técnicas Biossensoriais/métodos
13.
Food Chem ; 431: 137108, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37595380

RESUMO

Glucosinolates (GLSs) are secondary plant metabolites with health-promoting effects found in Brassica vegetables. Recently, next to non-enzymatic degradation yielding nitriles, 4-(methylthio)butyl GLS (4MTB-GLS) was shown to undergo side chain oxidation during thermal treatment, forming 4-(methylsulfinyl)butyl GLS (4MSOB-GLS). Here, we investigated natural plant components and artificial analogs on their capability of altering the thermal reactivity of 4MTB-GLS in vegetable broths and model systems using buffers. Addition of ascorbic acid and dehydroascorbic acid caused varying effects: in broth samples, it increased nitrile formation, while in buffer, 4MSOB-GLS was formed. In further experiments, the antioxidant compounds quercetin and Trolox triggered the side chain oxidation of 4MTB-GLS, while H2S terminated its degradation. A synergistic effect of ascorbic acid and Fe2+ was observed, degrading 98% of 4MTB-GLS to the nitrile after 60 min of boiling. Deepening the understanding of factors that influence the non-enzymatic degradation of GLSs will help to preserve their health-promoting effects.


Assuntos
Brassica , Verduras , Glucosinolatos , Oxirredução , Ácido Ascórbico , Nitrilas
14.
Food Microbiol ; 117: 104389, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37919001

RESUMO

Ready-to-eat fruit and vegetables are a convenient source of nutrients and fibre for consumers, and are generally safe to eat, but are vulnerable to contamination with human enteric bacterial pathogens. Over the last decade, Salmonella spp., pathogenic Escherichia coli, and Listeria monocytogenes have been linked to most of the bacterial outbreaks of foodborne illness associated with fresh produce. The origins of these outbreaks have been traced to multiple sources of contamination from pre-harvest (soil, seeds, irrigation water, domestic and wild animal faecal matter) or post-harvest operations (storage, preparation and packaging). These pathogens have developed multiple processes for successful attachment, survival and colonization conferring them the ability to adapt to multiple environments. However, these processes differ across bacterial strains from the same species, and across different plant species or cultivars. In a competitive environment, additional risk factors are the plant microbiome phyllosphere and the plant responses; both factors directly modulate the survival of the pathogens on the leaf's surface. Understanding the mechanisms involved in bacterial attachment to, colonization of, and proliferation, on fresh produce and the role of the plant in resisting bacterial contamination is therefore crucial to reducing future outbreaks.


Assuntos
Doenças Transmitidas por Alimentos , Listeria monocytogenes , Animais , Humanos , Frutas/microbiologia , Verduras/microbiologia , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Salmonella , Escherichia coli , Surtos de Doenças , Microbiologia de Alimentos
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 305: 123479, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37806239

RESUMO

In this paper, a novel coumarin-derived fluorescent probe NY was designed and synthesized. NY displayed a significant ratiometric fluorescence response towards Cu2+ in PBS buffer (10 mM, pH = 7.4), with the emission wavelength blue-shifted from 580 to 495 nm, and a fluorescence change from orange to green was evident under a 365 nm UV light. Meanwhile, NY had the advantages of high selectivity, short response time (5 min), low detection limit (1.3 × 10-8 M) and large binding constant (1.45 × 105 M-1) towards Cu2+. The binding mechanism between NY and Cu2+ was elucidated by FT-IR, 1H NMR titration, TOF-MS and Job's plot analysis. In addition, NY was successfully employed in the detection of Cu2+ within environmental water and vegetable samples with satisfactory results. Laser confocal microscopy imaging results showed that NY could easily penetrate HeLa cells membrane to target mitochondria and image Cu2+ in living cells. Furthermore, NY demonstrated mechanochromic properties by exhibiting orange-red fluorescence when subjected to mechanical grinding.


Assuntos
Cobre , Corantes Fluorescentes , Humanos , Espectrometria de Fluorescência/métodos , Cobre/análise , Corantes Fluorescentes/química , Verduras , Células HeLa , Espectroscopia de Infravermelho com Transformada de Fourier , Cumarínicos/química
16.
Sci Total Environ ; 908: 168252, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37918729

RESUMO

China produces more than half of global vegetables with greenhouse farms contributes approximately 35 % to the country's overall vegetable supply. The average nitrogen (N) application rate of greenhouse vegetable production exceeds 2000 kg N ha-1 yr-1, considerably contributing to global agricultural GHG emissions and reactive N (Nr) losses. Optimizing the N fertilizer utilization in greenhouse vegetable production is essential for mitigating environmental pollution and promoting sustainable development nationally and globally. In this study, we estimated the N footprint (NF), social costs (SC, which includes ecosystem and human health damage costs caused by Nr losses to the environment) and net ecosystem economic income (NEEI, which balances between the fertilizers input cost, yield profit, and social costs) of different greenhouse vegetables (tomato, pakchoi, lettuce, cabbage) under farmers' practice (FP) and reduced fertilization treatment (R). Results showed that compared with FP, the NF of tomato, pakchoi, lettuce and cabbage in the R treatment decreased by 61 %, 29 %, 46 % and 36 %, respectively, and the social costs were decreased by 60 %, 48 %, 57 % and 50 %, respectively. On the regional scale, the reduction in N fertilizer use for greenhouse vegetables in Beijing only could save the fertilizer input cost by 1-5 million USD, and avoided SC would increase by 1-14 million USD. As a result, this increased the NEEI by 2-19million USD. This study has demonstrated that adopting reduced fertilization practices represents a cost-effective measure that not only ensures yields but also decrease social costs, NF, and improve the benefits to help achieve sustainable development of greenhouse vegetable production.


Assuntos
Brassica , Verduras , Humanos , Ecossistema , Fertilizantes , Agricultura/métodos , Alface , Fertilização , Fatores Socioeconômicos , China , Nitrogênio , Solo , Óxido Nitroso/análise
17.
Sci Total Environ ; 908: 168270, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37918751

RESUMO

Rice-vegetable rotation practices prevail in subtropical and tropical agriculture worldwide, with applications of current-use herbicides (CUHs) vital for nontarget plant control. After application, CUHs migrate to environmental compartments, where the occurrence, fate, and ecological risks have not been well characterized. To further understand the occurrence and multiphase partitioning, as well as to evaluate potential drivers and mixture risks in environmental compartments, we analyzed 11 CUHs in 576 samples from 36 rice-vegetable rotations in Nandu River basin, Hainan, China. Samples included soil, water, suspended particulate matter, and sediment collected during both rice and vegetable planting periods. The CUH concentrations varied across environmental compartments, but with high levels of glyphosate and aminomethylphosphonic acid organophosphorus herbicides (OPHs) frequently detected, accounting for 82.3 % to 99.0 % in environmental compartments. Phenoxy acid (PAA) and chloroacetanilide (ANH) herbicides were detected at lower frequencies. Spatiotemporal variation was significantly different among OPHs, ANHs, and PAAs, with geographic and crop-related patterns most evident for CUHs rather than OPHs. Structural equation model, redundancy, and boosted regression tree analyses indicated environmental compartment properties (pH, organic matter, and Fe/Al oxides), crop type, and wet/dry climate were important drivers of spatiotemporal patterns. Fugacity ratios indicated multiphase partitioning and transport of CUHs differed in rice and vegetable planting periods. A new assessment framework based on species-sensitive distributions and environmental compartment weight index indicated unacceptable risks of CUHs (risk quotient >1 in >50 % of sites), with most risks from OPHs (10.5 % to 98.0 %) and butachlor, acetochlor, and 2,4-dichlorophenoxyacetic acid. Risk hot spots were identified as the soil, the central region, and the vegetable planting period, potentially threatening nontarget organisms (e.g., Lemna minor, Glomus intraradices, and Apis mellifera). This study provides a new risk assessment framework and demonstrates the domination of OPHs in CUH contamination and risks in the tropics, thus helping guide policymakers and stakeholders on herbicide management.


Assuntos
Herbicidas , Oryza , Animais , Abelhas , Herbicidas/análise , Verduras , Rios/química , Monitoramento Ambiental , Solo/química , China
18.
Environ Res ; 240(Pt 2): 117453, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37863165

RESUMO

Cultivation of the seaweed, Gracilariopsis lemaneiformis, supports environmental bioremediation and the aquaculture economy in coastal ecosystems, and microorganisms play important roles during the cultivation process. In this study, we aimed to understand the response of bacterial communities through a full cultivation cycle of G. lemaneiformis. We analyzed the bacterial communities using 16S rRNA gene amplicon sequencing and defined the environmental factors of 144 water samples from the Nan'ao Island, South China Sea. Community diversity, keystone species and ecological networks of bacterial communities shifted markedly in the cultivation zone largely due to changes in the environmental factors, seaweed biomass and cultivation stages. The bacterial communities at the seaweed zone have lower species richness, more seaweed-associated taxa and simpler but more stable co-occurrence networks compared to the control zone. Persistent microbial groups such as Aquimarina, Formosa, Glaciecola and Marinobacter exhibited a strong association with seaweed during the growth and maturity stages. We describe a conceptual model to summarize the changes in the bacterial community composition, its diversity and the ecological networks in seaweed cultivation zone. Overall, this study provides new perspectives on the dynamic interaction of seaweed cultivation, bacterial communities and environment factors and their potential ecosystem services as observed in the example of the G. lemaneiformis cultivation ecosystem.


Assuntos
Alga Marinha , Ecossistema , RNA Ribossômico 16S/genética , Aquicultura , Biomassa , Verduras
19.
J Environ Sci (China) ; 137: 245-257, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37980012

RESUMO

A novel alkalizing strain Enterobacter sp. LYX-2 that could resist 400 mg/L Cd was isolated from Cd-contaminated soil, which immobilized 96.05% Cd2+ from medium. Cd distribution analysis demonstrated that more than half of the Cd2+ was converted into extracellular precipitated Cd through mobilization of the alkali-producing mechanism by the strain LYX-2, achieving the high immobilization efficiency of Cd2+. Biosorption experiments revealed that strain LYX-2 had superior biosorption capacity of 48.28 mg/g for Cd. Pot experiments with Brassica rapa L. were performed with and without strain LYX-2. Compared to control, 15.92% bioavailable Cd was converted to non-bioavailable Cd and Cd content in aboveground vegetables was decreased by 37.10% with addition of strain LYX-2. Available Cd was mainly immobilized through extracellular precipitation, cell-surface biosorption and intracellular accumulation of strain LYX-2, which was investigated through Cd distribution, Scanning Electron Microscope and Energy-Dispersive X-ray Spectroscopy (SEM-EDS), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscopy (TEM) analysis. In addition, the application of strain LYX-2 significantly promoted the growth of vegetables about 2.4-fold. Above results indicated that highly Cd-resistant alkalizing strain LYX-2, as a novel microbial passivator, had excellent ability and reuse value to achieve the remediation of Cd-contaminated soil coupled with safe production of vegetables simultaneously.


Assuntos
Enterobacter , Poluentes do Solo , Enterobacter/metabolismo , Cádmio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Biodegradação Ambiental , Verduras , Solo/química , Poluentes do Solo/análise
20.
Sci Total Environ ; 906: 167447, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37788781

RESUMO

A recent study revealed the presence of non-pesticide organothiophosphate esters (OTPEs) - precursors to organophosphate esters (OPEs) contaminants - in river water. Since OPEs have demonstrated adverse reproductive outcomes in humans, this accentuates the urgency to explore the prevalence of non-pesticide OTPEs in other potential human exposure matrices. In this study, a nontarget screening method based on high-resolution mass spectrometry was used to identify OTPEs in food contact plastic (FCP) samples collected from South China. O,O,O-triphenyl phosphorothioate (TPhPt) and O,O,O-tris(2,4-di-tert-butylphenyl) phosphorothioate (AO168 = S) were unequivocally identified (Level 1), while O,O-di(di-butylphenyl) O-methyl phosphorothioate (BDBPMPt) was tentatively identified (Level 2b, indicating probable structure based on diagnostic evidence). Among n = 70 FCP samples, AO168 = S emerged with the highest detection frequency and median concentration of 74 % and 111 ng/g, respectively. Significant Pearson correlations were observed in log-transformed peak areas of AO168 = S and TPhPt in FCPs with their respective oxons, respectively. Occurrences of AO168 = S and TPhPt were further investigated in n = 100 foodstuff samples using a market basket method. AO168 = S and TPhPt exhibited detection frequencies of 43 % and 44 % in all food items with mean concentrations of 2.17 ng/g wet weight (ww) (range: <0.53-67.8 ng/g ww) and 0.112 ng/g ww (range: <0.006-2.39 ng/g ww), respectively. The highest mean concentrations for AO168 = S and TPhPt were found in vegetables (4.62 ng/g ww) and oil (3.00 ng/g ww), respectively. The median estimated daily intakes (EDIs) of AO168 = S and TPhPt via diet were calculated as 10.4 and 1.51 ng/kg body weight/day, respectively. For AO168 = S, only meat and vegetables contributed to the median EDI, whereas for TPhPt, oil was identified as the principal contributor to the median EDI. This study for the first time evaluated human exposure to OTPEs via diet, providing new insights to overall human exposure to OPEs.


Assuntos
Ésteres , Retardadores de Chama , Humanos , Ésteres/análise , Fosfatos/análise , Organofosfatos/análise , China , Verduras , Ingestão de Alimentos , Retardadores de Chama/análise , Monitoramento Ambiental/métodos
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