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1.
Chemosphere ; 279: 130902, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134438

RESUMO

Various veterinary antibiotics (VAs) are used in large quantities as an essential component for intensive livestock farming, and can flow into the environment from various pollution sources. In this study, VAs in surface water and groundwater in the Gwangcheon stream watershed, an intensive livestock farming area in Korea, were analyzed using ultra-high-performance liquid chromatograph-quadrupole orbitrap high-resolution mass spectrometer with online solid phase extraction. Although the selected VAs are relatively mobile and have low KOW values it is significant to assess their fates and ecological risks in the environment. The concentration of VAs in the surface water was higher than that in groundwater by approximately 23-fold, indicating that the former were directly introduced from pollution sources such as livestock manure. An analysis of the correlation between livestock manure production and the residuals of VAs in the stream showed a high linearity (R2 > 0.70), confirming that livestock excreta significantly contributed to the VAs in the watershed. A combined evaluation of environmental behaviors and ecological risks of VAs was performed for the first time using persistence, bioaccumulation potential, and toxicity properties and risk quotient values of VAs. Trimethoprim showed persistence and a potential impact on the ecosystem. The cumulative risk quotient values at one sampling point exceeded 1 indicating that several VAs can cumulatively cause local risk. The risk assessment method considering pollution sources, different locations, and correlation analysis applied in this study will be useful in evaluating the impacts of trace pollutants in watersheds.


Assuntos
Gado , Esterco , Agricultura , Animais , Antibacterianos/análise , Antibacterianos/toxicidade , Ecossistema , Monitoramento Ambiental , Esterco/análise , República da Coreia , Medição de Risco
2.
Molecules ; 26(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073447

RESUMO

Food preservatives such as NaNO2, which are widely used in human food products, undoubtedly affect, to some extent, human organs and health. For this reason, there is a need to reduce the hazards of these chemical preservatives, by replacing them with safe natural bio-preservatives, or adding them to synthetic ones, which provides synergistic and additive effects. The Citrus genus provides a rich source of such bio-preservatives, in addition to the availability of the genus and the low price of citrus fruit crops. In this study, we identify the most abundant flavonoids in citrus fruits (hesperidin) from the polar extract of mandarin peels (agro-waste) by using spectroscopic techniques, as well as limonene from the non-polar portion using GC techniques. Then, we explore the synergistic and additive effects of hesperidin from total mandarin extract with widely used NaNO2 to create a chemical preservative in food products. The results are promising and show a significant synergistic and additive activity. The combination of mandarin peel extract with NaNO2 had synergistic antibacterial activity against B. cereus, Staph. aureus, E. coli, and P. aeruginosa, while hesperidin showed a synergistic effect against B. cereus and P. aeruginosa and an additive effect against Staph. aureus and E. coli. These results refer to the ability of reducing the concentration of NaNO2 and replacing it with a safe natural bio-preservative such as hesperidin from total mandarin extract. Moreover, this led to gaining benefits from their biological and nutritive values.


Assuntos
Antibacterianos/análise , Citrus/química , Contaminação de Alimentos/prevenção & controle , Hesperidina/química , Nitrito de Sódio/química , Antioxidantes/análise , Bacillus cereus , Sinergismo Farmacológico , Escherichia coli , Flavonoides/química , Conservantes de Alimentos , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Pseudomonas aeruginosa , Staphylococcus aureus
3.
Food Chem ; 362: 130261, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111691

RESUMO

In this study, a novel surface enhanced Raman spectroscopy (SERS) sensor was developed for the ultrasensitive determination of kanamycin in foods. The sensor used two distinct signal amplification strategies, namely the surface plasmon resonance of gold nanorods and a Zn-doped carbon quantum dots catalytic cascade oxidation-reduction reaction switch controlled by a nucleic acid aptamer. Under optimized experimental conditions, the SERS sensor demonstrated a linear range of 10-12 to 10-5 g mL-1 for the detection of kanamycin, with a limit of detection of 3.03 × 10-13 g mL-1. Experiments with antibiotics structurally similar to kanamycin and interferrants revealed that the sensor had excellent selectivity. Milkpowder and honey samples spiked with kanamycin were assayed, with recoveries ranging from 84.1% to 107.2% and a relative standard deviation of 0.74% to 2.81% being obtained. Quantification of kanamycin in milk samples revealed no significant difference between the results obtained with the sensor and by HPLC.


Assuntos
Aptâmeros de Nucleotídeos/química , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Canamicina/análise , Nanotubos/química , Pontos Quânticos/química , Zinco/química , Antibacterianos/análise , Técnicas Biossensoriais/instrumentação , Carbono/química , Catálise , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Ressonância de Plasmônio de Superfície
4.
Molecules ; 26(10)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063344

RESUMO

Safety and quality are key issues for the food industry. Consequently, there is growing demand to preserve the food chain and products against substances toxic, harmful to human health, such as contaminants, allergens, toxins, or pathogens. For this reason, it is mandatory to develop highly sensitive, reliable, rapid, and cost-effective sensing systems/devices, such as electrochemical sensors/biosensors. Generally, conventional techniques are limited by long analyses, expensive and complex procedures, and skilled personnel. Therefore, developing performant electrochemical biosensors can significantly support the screening of food chains and products. Here, we report some of the recent developments in this area and analyze the contributions produced by electrochemical biosensors in food screening and their challenges.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Inocuidade dos Alimentos/métodos , Antibacterianos/análise , Cadeia Alimentar , Humanos , Praguicidas/análise , Toxinas Biológicas/análise
5.
J Chromatogr A ; 1650: 462256, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34082187

RESUMO

An analytical method based on low-temperature partitioning extraction (LTPE) followed by high performance liquid chromatography coupled to triple quadrupole mass spectrometry analysis was developed and validated for the determination of eight multiclass antibiotics in wastewater. The analyzed target antibiotics included one ß-lactam, two sulfonamides, three fluoroquinolones, one macrolide and one diaminopyrimidine. LTPE parameters such as sample pH, volume ratio between sample and extractor solvent, ultra-sonic extraction time, extraction tube material, solvent and volume to reconstitute the sample extracts, were optimized. Additionally, the influence of solids on extraction efficiency was evaluated. Quantification of the target antibiotics was performed by double consecutive injection method, without the use of a labeled compound, in order to correct matrix effects. The whole samples were analyzed, including, liquid and solid fractions of wastewater. The results revealed that the filtration step can underestimate the total antibiotics concentration, particularly to the hydrophobic compounds that have higher affinity for solids, indicating that the suspended wastewater particulate should not be neglected. The method detection limit ranged from 18.54 ng L-1 (trimethoprim) to 78.49 ng L-1 (ciprofloxacin). Intra-day precision of less than 12.3% was achieved. The recoveries values ranged from 13.9% (sulfadiazine) to 48.9% (erythromycin) in influent samples and from 19.1% (sulfadiazine) to 57.2% (ciprofloxacin) in effluent samples. The method was applied to the measurement of antibiotic residues in influent and effluent from wastewater treatment plants. The majority target antibiotics were detected in wastewater samples. Their concentrations ranged from 237 to 9553 ng L-1 in influent and from 212 to 1660 ng L-1 in effluent. This work provides new insights on the applicability of LTPE for antibiotic residues extraction from wastewater. In addition, the performed analysis highlights the importance of measuring total concentrations of analytes in whole sample.


Assuntos
Antibacterianos , Técnicas de Química Analítica , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Águas Residuárias , Poluentes Químicos da Água , Antibacterianos/análise , Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Temperatura Baixa , Interações Hidrofóbicas e Hidrofílicas , Extração em Fase Sólida , Águas Residuárias/química , Poluentes Químicos da Água/análise
6.
Anal Chim Acta ; 1173: 338569, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34172150

RESUMO

Several antibiotics have been applied to veterinary medicine due to their broad-spectrum of antibacterial activity and prophylactic power. Residues of these antibiotics can be accumulated in dairy cattle, in addition to promoting contamination of the environment and, in more serious cases, in milk, causing a public health problem. Different regulatory agencies establish maximum residue limits for these antibiotics in milk, so it becomes important to develop sensitive analytical methods for monitoring these compounds. Electrochemical techniques are important analytical tools in analytical chemistry because they present low cost, simplicity, high sensitivity, and adequate analytical frequency (sample throughput) for routine analyses. In this sense, this review summarizes the state of the art of the main electrochemical sensors and biosensors, instrumental techniques, and sample preparation used for the development of analytical methods, published in the last five years, for the monitoring of different classes of antibiotics: aminoglycosides, amphenicols, beta-lactams, fluoroquinolones, sulfonamides, and tetracyclines, in milk samples. The different strategies to develop electrochemical sensors and biosensors are critically compared considering their analytical features. The mechanisms of electrochemical oxidation/reduction of the antibiotics are revised and discussed considering strategies to improve the selectivity of the method. In addition, current challenges and future prospects are discussed.


Assuntos
Resíduos de Drogas , Leite , Animais , Antibacterianos/análise , Bovinos , Resíduos de Drogas/análise , Técnicas Eletroquímicas , Contaminação de Alimentos/análise , Leite/química , Tetraciclinas/análise
7.
Huan Jing Ke Xue ; 42(6): 2748-2757, 2021 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-34032074

RESUMO

In view of the lack of ecotoxicological data for most antibiotics in China's water environment, national-scale ecological risk assessment of antibiotics remains impossible. This study determined the exposure index values for antibiotic products in the National Medical Products Administration based on quantity and average daily dose data for all antibiotics in the market alongside exposure modeling. The risk scores were calculated using data on the ecotoxicological effects of the antibiotics, and the species sensitivity distributions (SSD) method and apical effects. Priorities for control were identified based on the findings. Approximately 105 antibiotics were screened, and 53 were identified as candidate drugs with high national usage. Twenty antibiotics were identified for priority risk evaluation using a joint probabilistic model, with clarithromycin, ciprofloxacin, amoxicillin, cefaclor, and oxyfloxacin highlighted as presenting a high ecological risk. This study provides a scientific basis for the quantitative assessment of antibiotic risk prevention and control in China's aquatic environment.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Antibacterianos/análise , Antibacterianos/toxicidade , China , Ciprofloxacina , Monitoramento Ambiental , Medição de Risco , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
8.
Food Chem ; 361: 130109, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34029899

RESUMO

Antibiotics are widely used in the prevention and treatment of infectious diseases in animals due to its bactericidal or bacteriostatic action. Residual antibiotics and their metabolites pose great threats to human and animal health, such as potential carcinogenic and mutagenic effects, and bacterial resistances. Therefore, it is necessary and urgent to accurately monitor trace amounts of antibiotics in food samples. Up to now, many analytical methods have been reported for the determination of antibiotics. Biosensors with the advantages of high sensitivity, rapid response, easy miniaturization, and low price have been widely applied to the detection of antibiotics residues in past decades. This review offered an in-depth evaluation of recognition elements for antibiotic residues in diverse food matrices. In addition, it presented a systematical and critical review on signal amplification via various materials, focusing on recently developed nanomaterials. Finally, the review provided an outlook on the future concepts to help upgrade the sensing techniques for antibiotics in food.


Assuntos
Antibacterianos/análise , Técnicas Biossensoriais/métodos , Limite de Detecção , Nanoestruturas/química , Nanotecnologia/métodos , Animais , Humanos
9.
J Hazard Mater ; 417: 125481, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-33992019

RESUMO

Large amounts of antibiotics are produced and consumed worldwide, while wastewater treatment is still rather inefficient, leading to considerable water contamination. Concentrations of antibiotics in the environment are often sufficiently high to exert a selective pressure on bacteria of clinical importance that increases the prevalence of resistance. Since the drastic reduction in the use of antibiotics is not envisaged, efforts to reduce their input into the environment by improving treatment of contaminated wastewater is essential to limit uncontrollable spread of antibiotic resistance. This paper reviews recent progress on the use of non-thermal plasma for the degradation of antibiotics in water. The target compounds removal, the energy efficiency and the mineralization are analyzed as a function of discharge configuration and the most important experimental parameters. Various ways to improve the plasma process efficiency are addressed. Based on the identified reaction intermediates, degradation pathways are proposed for various classes of antibiotics and the degradation mechanisms of these chemicals under plasma conditions are discussed.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Antibacterianos/análise , Resistência Microbiana a Medicamentos , Águas Residuárias , Água , Poluentes Químicos da Água/análise
10.
J Environ Sci (China) ; 104: 415-429, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33985744

RESUMO

Once contaminate the drinking water source, antibiotic resistance genes (ARGs) will propagate in drinking water systems and pose a serious risk to human health. Therefore, the drinking water treatment processes (DWTPs) are critical to manage the risks posed by ARGs. This study summarizes the prevalence of ARGs in raw water sources and treated drinking water worldwide. In addition, the removal efficiency of ARGs and related mechanisms by different DWTPs are reviewed. Abiotic and biotic factors that affect ARGs elimination are also discussed. The data on presence of ARGs in drinking water help come to the conclusion that ARGs pollution is prevalent and deserves a high priority. Generally, DWTPs indeed achieve ARGs removal, but some biological treatment processes such as biological activated carbon filtration may promote antibiotic resistance due to the enrichment of ARGs in the biofilm. The finding that disinfection and membrane filtration are superior to other DWTPs adds weight to the advice that DWTPs should adopt multiple disinfection barriers, as well as keep sufficient chlorine residuals to inhibit re-growth of ARGs during subsequent distribution. Mechanistically, DWTPs obtain direct and inderect ARGs reduction through DNA damage and interception of host bacterias of ARGs. Thus, escaping of intracellular ARGs to extracellular environment, induced by DWTPs, should be advoided. This review provides the theoretical support for developping efficient reduction technologies of ARGs. Future study should focus on ARGs controlling in terms of transmissibility or persistence through DWTPs due to their biological related nature and ubiquitous presence of biofilm in the treatment unit.


Assuntos
Água Potável , Purificação da Água , Antibacterianos/análise , Água Potável/análise , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos
11.
Sci Total Environ ; 787: 147554, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34004531

RESUMO

Antibiotic levels in black-odor water could reflect the usage amount of antibiotics in population. On the other hand, these antibiotics are the source of antibiotics in the environmental water. Currently, researches on antibiotics in black-odor sediments are still lacking. In this study, 174 black and odor sediment samples from 74 cities in 28 provinces in China were collected for analysis. Among 44 targeted antibiotics, 13 antibiotics were detected in more than 30% of sediment samples. Fluoroquinolones and tetracyclines were the predominant antibiotics in these field samples, with average concentrations of up to 2074 and 1902 ng/g dry weight (dw), respectively, followed by macrolides (87.9 ng/g dw), lincosamides (8.06 ng/g dw) and sulfonamides (8.38 ng/g dw). High antibiotic contamination levels were almost always detected in black-odor sludges from economically less developed small cities; however, the difference in antibiotic concentrations between well-developed and small cities in China was not statistically significant. In addition, among the seven regions within China, no significant difference in concentrations was observed for the most antibiotics. Variances in antibiotic composition patterns in the 28 provinces of China may be due to differences in bacterial resistance, prescription habits, efficacy, and sediment carbon concentrations among various regions. There were significant positive correlations among some antibiotics in the same or different classes.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água , Afro-Americanos , Antibacterianos/análise , China , Cidades , Monitoramento Ambiental , Humanos , Odorantes , Poluentes Químicos da Água/análise
12.
J Chromatogr A ; 1645: 462074, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-33848656

RESUMO

We prepared two-dimensional (2D) bimetallic metal-organic frameworks (Ni-ZIF-8) nanosheets by a simple solvent-free method at room temperature. The morphology and composition of Ni-ZIF-8 can be controlled through adding different amounts of Ni. And then, the 2D magnetic mesoporous nanosheets (Ni/ZnO@C) were synthesized by directly pyrolyzing Ni-ZIF-8 under argon atmosphere and explored as magnetic solid phase extraction (MSPE) adsorbents for the determination of nitroimidazole antibiotics (NIABs). Magnetic Ni nanoparticles embedded in carbon nanosheets uniformly resulted in high magnetization saturation of Ni/ZnO@C for easy separation. The Ni/ZnO@C can form hydrogen bond and π-π interaction with three NIABs resulting from their rich N-H containing imidazole, π-electron. Due to the high specific surface area and high mass transfer rate of 2D Ni/ZnO@C, the materials showed satisfactory adsorption capacity and rapid adsorption kinetics for NIABs. A rapid and effective method of Ni/ZnO@C-MSPE combined with high-performance liquid chromatography was proposed for the determination of NIABs. Several main parameters affecting MSPE were investigated. Under the optimal conditions, wide linear was achieved ranging from 0.1 to 500 µg⋅L-1 with a low detection limit of 0.025-0.05 µg⋅L-1. The established method has been successfully applied to analyze NIABs from environmental water samples with satisfactory recovery from 74.33 to 105.71%.


Assuntos
Antibacterianos , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Nitroimidazóis , Extração em Fase Sólida/métodos , Antibacterianos/análise , Antibacterianos/isolamento & purificação , Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Modelos Lineares , Imãs/química , Nanoestruturas/química , Níquel/química , Nitroimidazóis/análise , Nitroimidazóis/isolamento & purificação
13.
Inorg Chem ; 60(8): 5764-5770, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33829775

RESUMO

Two NIR luminescent Zn(II)/Cd(II)-Yb(III) complexes were obtained by the use of a Schiff base ligand with a binaphthyl backbone. Cd(II)-Yb(III) complex 2 has a triangular structure and exhibits interesting luminescent sensing activity to antibiotics, in particular to ciprofloxacin (CPFX) and norfloxacin (NFX) due to the inner filter effect. The limits of the detection of 2 to CPFX and NFX are 0.18 and 0.36 µM, respectively, and the fluorescence sensitivity is not changed with the existence of other antibiotics tested in this study.


Assuntos
Antibacterianos/análise , Cádmio/química , Fluoroquinolonas/análise , Substâncias Luminescentes/química , Itérbio/química , Zinco/química , Raios Infravermelhos , Substâncias Luminescentes/síntese química , Medições Luminescentes , Estrutura Molecular , Bases de Schiff/química
14.
J Food Sci ; 86(5): 2145-2162, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33928644

RESUMO

In this work, the occurrence of 34 common antibiotic (15 sulfonamides and 19 quinolones) residues were evaluated in 236 ready-to-eat duck eggs (salted and preserved duck eggs) marketed through e-commerce stores by ultra-performance liquid chromatography coupled to tandem mass spectrometry, and subsequent dietary risk assessments for Chinese consumers were conducted. Among violated positives in duck egg samples, 11 analytes were found including sulfamethazine, sulfaquinoxaline, sulfamethoxazole, sulfadiazine, sulfamonomethoxine, ciprofloxacin, enrofloxacin, ofloxacin, flumequine, sarafloxacin, and nalidixic acid. A higher number of antibiotics were detected in salted duck eggs (five sulfonamides and six quinolones) than in preserved duck eggs (one sulfonamide and two quinolones). The maximum contamination of sulfonamides and quniolones was 448.0 µg/kg (sulfaquinoxaline) and 563.7 µg/kg (enrofloxacin) in salted duck eggs, respectively. Dietary exposure was evaluated through the estimated daily intake (EDI) of risky antibiotics (sulfamethazine, ciprofloxacin, and enrofloxacin) and hazard quotients (HQs). The results showed that EDIs and HQs were in the range of 0.0004 to 0.0099 µg/kg bw/day and 0.0009 to 0.1594%, respectively. The risk was low since HQs obtained were less than 100%. However, a special attention should be paid to ready-to-eat duck egg products high percentile consumers with the prosperity of e-commerce market in China. PRACTICAL APPLICATION: The present analytical method could be used for multiresidue determination of antibiotics in ready-to-eat duck eggs, and dietary risk assessments of risky antibiotics provided a support for the work of regulatory bodies to conduct surveillance programs regarding food safety evaluation of ready-to-eat foods.


Assuntos
Antibacterianos/análise , Comércio/normas , Qualidade de Produtos para o Consumidor/normas , Ovos/análise , Contaminação de Alimentos/análise , Medição de Risco/métodos , Animais , China , Cromatografia Líquida/métodos , Patos , Espectrometria de Massas em Tandem/métodos
15.
Molecules ; 26(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806573

RESUMO

In this work, for the first time, Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry (UHPLC-MS/MS) method was developed for qualitative and quantitative analysis of veterinary antibiotics (cephalosporins, diaminopyrimidines, fluoro(quinolones), lincosamides, macrolides, penicillins, pleuromutilins, sulfonamides, tetracyclines, and sulfones) in hen eggshells. The sample preparation method is based on a liquid-liquid extraction with a mixture of metaphosphoric acid, ascorbic acid, EDTA disodium salt dihydrate, and acetonitrile. The chromatographic separation was performed on Luna® Omega Polar C18 10 column in gradient elution mode and quantitated in an 8 min run. Validation such as linearity, selectivity, precision, recovery, matrix effect, limit of quantification (LOQ), and limit of detection (LOD) was found to be within the acceptance criteria of the validation guidelines of the Commission Decision 2002/657/EC and EUR 28099 EN. Average recoveries ranged from 81-120%. The calculated LOQ values ranged from 1 to 10 µg/kg, the LOD values ranged from 0.3 to 4.0 µg/kg, depending on analyte. The developed method has been successfully applied to the determination of antibacterial compounds in hen eggshell samples obtained from different sources. The results revealed that enrofloxacin, lincomycin, doxycycline, and oxytetracycline were detected in hen eggshell samples.


Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Casca de Ovo/química , Extração Líquido-Líquido/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Antibacterianos/isolamento & purificação , Galinhas
16.
J Chromatogr A ; 1646: 462089, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33848643

RESUMO

As an important natural product, the sufficient separation of plant essential oil (EO) is helpful to improve its utilization value. In this work, deep eutectic solvent-homogenate based microwave-assisted hydrodistillation (DES-HMAHD) was developed and applied to isolate EO from the fruits of Litsea cubeba (Lour.) Pers. Different types of DES were investigated in terms of the EO kinetics and composition, among which oxalic acid/choline chloride (OA/ChCl) had obvious advantages. Following, molar ratio of OA and ChCl (1:1), water content (50%), liquid-solid ratio (12.5:1 mL/g), homogenate time (2 min), and microwave power (700 W) were found to be the optimum conditions. Gas chromatography-mass spectrometer (GC-MS) analysis showed that the EO isolated from DES-HMAHD contained a large proportion of m-cymene and trans-linalool oxide, which were quite different from the conventionally reported L. cubeba EO. In addition, the proposed DES-HMAHD resulted in higher separation efficiency and economic value, as well as lower environmental impact, as compared with other techniques. Afterwards, the EO isolated by different methods was evaluated from the perspective of biological activity. The EO obtained by DES-HMAHD showed higher antioxidant activity (DPPH and ABTS) but lower antifungal activity, which was related to its chemical composition. In general, DES-HMAHD produced a kind of L. cubeba EO with different components, which provided a scientific foundation for the sufficient isolation of plant EO and its application in the natural products.


Assuntos
Litsea/química , Micro-Ondas , Óleos Voláteis/química , Monoterpenos Acíclicos , Antibacterianos/análise , Antioxidantes/análise , Cicloexanóis , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Vegetais/análise , Solventes/análise , Compostos de Tritil
17.
Anal Methods ; 13(13): 1550-1558, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33861252

RESUMO

Rabbit polyclonal antibodies were generated against the ionophore antibiotic salinomycin (SAL) as a determinant of the BSA-SAL conjugate. The homologous ELISA format was found to be preferred for similar recognition of SAL and narasin (NAR) with IC50 values of 0.55 and 0.57 ng mL-1, respectively. Both analytes could be determined in the range of 0.1-2.7 ng mL-1 (IC20-IC80) with a detection limit of 0.03 ng mL-1. To analyze matrices, individual pretreatment of samples was required. For chicken muscles, simple buffer extraction was sufficient to recover 87-110% of ionophores. Extraction with acetonitrile followed by evaporation of the solvent was best for recovering 67-108% SAL and NAR from egg homogenate. A feature of the extraction of ionophores from milk was the elimination of fat-mediated interference by organic solvation. It was found that the absence of Na+ and K+ ions during reconstitution of sample extracts was a key factor contributing to the increase in the average recovery of ionophores from 32% to 93%. Thanks to this special pretreatment and improved recovery, the developed immunoassay method was suitable for the analysis of ionophore antibiotics SAL and NAR in a milk matrix, which has not been previously reported.


Assuntos
Antibacterianos , Leite , Animais , Antibacterianos/análise , Ionóforos/análise , Leite/química , Produtos Avícolas , Piranos , Coelhos
18.
Chemosphere ; 279: 130381, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33878699

RESUMO

The spatiotemporal distribution, source apportionment and combined pollution of 14 antibiotics in natural waters adjacent to mariculture farms of Laizhou Bay in the Bohai Sea were studied. The contribution proportion and quantity of each potential pollution source to antibiotics in natural water bodies were quantitatively described. The correlations between heavy metals and antibiotics and their underlying mechanisms in natural and aquaculture water environment were analyzed. Fourteen antibiotics were detected in natural water and sediment in the coastal area of Laizhou Bay. The maximum concentrations of sulfamethazine and trimethoprim in water reached tens or even hundreds of µg/L in winter. Trimethoprim was the main antibiotic in natural water bodies in winter and summer, and enrofloxacin was the principal antibiotic in sediments. Enrofloxacin, ciprofloxacin and oxytetracycline were detected in all underground water samples; thus, control of these antibiotics needs to be made a priority to mitigate groundwater contamination. PCA-MLR revealed that the potential sources of antibiotics in natural waters of Laizhou Bay include the mariculture wastewater (18.3%), the domestic sewage (63.3%) and the livestock wastewater (18.4%). Therefore, the antibiotic burden of Laizhou Bay was principally from the domestic sewage. In natural water, the concentration of Cu was positively correlated with antibiotics, which might be related to the common sources, the competitive adsorption in sediments and the easy complexation characteristic of Cu and antibiotics. Positive correlations among antibiotics and heavy metals were observed in mariculture sediments, while negative relationships were observed in natural sediments.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Antibacterianos/análise , Baías , China , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Poluentes Químicos da Água/análise
19.
Environ Pollut ; 281: 116980, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33799209

RESUMO

Coastal tourist and industrial cities are most likely to have differential effects on the distance dilution of antibiotic resistance genes (ARGs) in an estuary system. This study used high-throughput fluorescence quantitative polymerase chain reaction to identify sediment ARGs in two typical estuaries of coastal tourist and industrial cities (Xiamen and Taizhou) in China. The distance dilution of ARGs and its relationship with key environmental factors were analysed. The results indicated that along the river inlet towards the sea, the distance dilution effect on ARG abundance in estuary sediments of Taizhou was approximately double that in Xiamen, and the macrolide, lincosamide, and streptogramin B (MLSB) and vancomycin genes were replaced by the fluoroquinolone, quinolone, florfenicol, chloramphenicol, and amphenicol (FCA) and ß-lactam genes in Taizhou, whereas ß-lactam genes succeeded the MLSB and sul genes in Xiamen. The abundance and number of ARGs and mobile genetic elements (MGEs) were positively correlated with the particle size and total organic carbon (TOC) contents of sediments, whereas they were negatively associated with the oxidation and reduction potential (Eh) and pH of sediments, as well as the seawater salinity. The sediment particle size (SPZ) was the dominant physicochemical factor affecting the abundance of ARGs (r = 0.826, p < 0.05) and MGEs (r = 0.850, p < 0.01). These findings suggest that although the distance dilution effect on the ARG abundance of estuary sediments of the industrial city is greater than that of the tourist city, the larger SPZ, higher TOC content, and lower salinity, pH, and Eh in estuary regions adjacent to the industrial city can more significantly facilitate the proliferation and propagation of ARGs in the sediments.


Assuntos
Antibacterianos , Estuários , Antibacterianos/análise , China , Cidades , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Sedimentos Geológicos
20.
Food Chem ; 356: 129659, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33812186

RESUMO

Oxytetracycline (OTC), one of the largely used antibiotic in veterinary practice has been banned due to its potential side effects. Development of a field applicable and affordable kit to detect OTC will help to eliminate such milk from human consumption. An aptamer has been designed (27 nt; Kd = 29.2 ± 19.4 nM) through rational truncation. OTC interacts with this aptamer in G rich regions as confirmed by molecular modelling and circular dichroism spectroscopy. To develop a lateral flow based aptasensor, OTC was conjugated with a 7 kDa carrier protein to immobilize onto the nitrocellulose membrane. Using 0.125 µM aptamer-gold conjugate, assay could visually detects upto 5 ng/mL of OTC in spiked milk within 10 mins [Limit of quantitation (LOQ)-0.254 ± 1.62 ng/mL; permissible limit 100 ng/mL]. It showed no cross reactivity with components of milk and data correlated with analysis done through HPLC.


Assuntos
Antibacterianos/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Leite/química , Oxitetraciclina/análise , Animais , Proteínas de Transporte/química , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Leite/metabolismo , Sistemas Automatizados de Assistência Junto ao Leito
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