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1.
Environ Technol ; : 1-13, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37729646

RESUMO

Antibiotics have several negative effects on aquatic ecosystems and are difficult to degrade using traditional water/wastewater treatment methods. As a result, new treatment techniques must be employed to eliminate these contaminants from aquatic environments. Research on the relationship between the decomposing process of antibiotics and different factors by new technologies is scarce. This research focuses on the capability of ozone micro-nano bubbles (OzMNBs) to eliminate the antibiotics ciprofloxacin (CIPR) and levofloxacin (LEVO) in aqueous solutions. We studied the CIPR and LEVO decomposition to different variables through the central composite design method. The main variables included pH, ozonation time, and initial antibiotic concentration. The correlation coefficients of the quadratic model obtained by using the software, Design Expert version 13.0.1. Analysis of variances proved the significance of models and main factors. Verification tests also confirmed that the final optimum conditions of the antibiotics decomposition were: pH 9, ozonation for 40 min and, initial antibiotic concentration of 5 mg/L. In optimum conditions, removal rate of about 97% and 100% was obtained for CIPR and LEVO, respectively. The order of influence of various factors on CIPR and LEVO decomposition were obtained and the interactions between the main factors were also investigated. At the last stage of the research, the efficiency of OzMNBs in the removal of total organic carbon and mineralization of the solutions containing CIPR and LEVO under optimum conditions was examined.

2.
Naunyn Schmiedebergs Arch Pharmacol ; 396(6): 1257-1267, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36715735

RESUMO

Although neuroprotective effects of granulocyte colony-stimulating factor (G-CSF) have been shown in rats exposed to carbon monoxide (CO), this pilot clinical trial was performed to assess the feasibility of treatment with G-CSF in patients with acute CO poisoning. A double-blind, randomized, placebo-controlled pilot clinical trial was conducted on twenty-six patients with acute CO poisoning. G-CSF (90 µg/kg) was administered intravenously for 72 h. Demographic data, routine laboratory tests, differential blood counts, venous blood gas, and adverse reactions were recorded. The primary endpoint was brain ischemia improvement based on CT findings and the secondary endpoints examined improvements in the modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), and Barthel Index as well as S-100ß concentrations. Fourteen patients received G-CSF, and 12 received a placebo. Twenty-six were followed for 30 days and no one in both groups died during follow-up. Neurological complications, brain ischemic changes, Barthel, and mRS were compared between the two groups on determined days after the onset of therapeutic intervention, and no significant differences were observed between the two groups. Favorable results were achieved for treated patients by different measures; NIHSS was decreased 72 h after treatment (p = 0.046), and S-100ß levels were significantly higher in the G-CSF group than in the control group, 12 h and 72 h after the treatment. G-CSF appears to have potential effects on several clinical parameters in patients with acute CO poisoning. The trial was registered at the Iranian Registry of Clinical Trials with the ID: (IRCT201607232083N7).


Assuntos
Intoxicação por Monóxido de Carbono , Fármacos Neuroprotetores , Ratos , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Projetos Piloto , Subunidade beta da Proteína Ligante de Cálcio S100 , Intoxicação por Monóxido de Carbono/tratamento farmacológico , Irã (Geográfico) , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Método Duplo-Cego , Resultado do Tratamento
3.
J Chromatogr A ; 1625: 461307, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709350

RESUMO

In this study, the ultrasonic-assisted dispersive solid phase extraction (UA-d-SPE) method coupled to gas chromatography-mass spectrometry (GC-MS) was applied for the analysis of phthalate esters in drinking water and distilled herbal beverages (Rosa, Mentha, Cichorium). A new nanocomposite based on layered double hydroxide supported on graphene oxide was synthesized and modified by sulfonated polyaniline via a simple one-pot in-situ polymerization method. The structure and morphology of the nanocomposite was confirmed by means of complementary techniques: Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and transmission electron microscopy. The effects of key parameters including adsorbent mass, type and amount of back extraction solvent, extraction and desorption time, pH of the solution and ionic strength were optimized and good precision and sensitivity were achieved. Under the optimum conditions, the limits of detection were between 0.06-0.3 ng mL-1 in aqueous solutions. The hybrid nanomaterial exhibited good adsorption ability toward phthalates in drinking water and distilled herbal beverages. The relative standard deviations (RSD%) for beverage samples varied from 0.1% to 9.9% (n = 3). The relative recoveries varied from 54.5% to 112.6%.


Assuntos
Compostos de Anilina/química , Bebidas/análise , Grafite/química , Hidróxidos/química , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida/métodos , Ácidos Sulfônicos/química , Ultrassom/métodos , Adsorção , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Nanocompostos/química , Concentração Osmolar , Ácidos Ftálicos/análise , Preparações de Plantas/química , Reprodutibilidade dos Testes , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Difração de Raios X
4.
Int J Biol Macromol ; 162: 163-174, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32534084

RESUMO

Although graphene oxide (GO) is a good adsorber, it has a low stability in pure form which can be improved by the development of GO-based composites. In this study, 3D nanostructures with GO, surface-decorated by nanocomplexes of chitosan (CS) and gum Arabic (GA), so called 3D GO-CS/GA nanocomposites were designed. The instrumental analysis confirmed the interaction of complexes with oxygenated functional groups of GO which improved both of d-spacing in 3D sheets by 16%, and GO thickness from 1.0 to 8.1 nm. Also, an unprecedented ~3-fold increase was observed in the surface area of 3D GO-CS/GA compared with single GO. The 3D nanocomposites showed a mesoporous structure with a pore volume of 0.72 cm3/g and a prevailing pore size distribution of about 10 nm. The adjustability of nanocomposite surface charge over pH was another important result. The synthesized nanostructures would be of profound interest for numerous areas including adsorption processes.


Assuntos
Quitosana/química , Grafite/química , Goma Arábica/química , Nanopartículas/química , Biopolímeros/química , Grafite/síntese química , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Propriedades de Superfície
5.
Chemosphere ; 245: 125639, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31864045

RESUMO

Consumption of food crops contaminated with heavy metals (HMs) is a significant risk factor for human health and safety. We evaluated the health risks of HMs in contaminated food crops irrigated with surface water. Results showed there is a substantial buildup of HMs in rice, collected from the Tajan river basin, Iran. The transfer factor (TF) value for toxic elements Cd (3.6-12.4) and Pb (4.9-23.6) were significantly high and exceeded the permissible limits for crops set by WHO. The principal component analysis was used to analyze the relevance of different metals and identify the primary sources. The results showed that two factors dominated the metals variability (94.10% of total variance) that Cr, Fe, Cd, and Pb were dominated by PC1 whereas another factor charged Zn and Cu. The average total hazard quotient (THQ) values for Pb, Fe, Cr, and Cd were 13.8, 7.7, 5.5, and 1.5, respectively, that suggest a considerable risk to the health of regular rice consumers. The high hazard index (HI) value (29.2) demonstrated that the exposure concentration was very high compared to the effective threshold, and it may have potentially harmful implications for human health. To sum up, these results proved that rice from this basin could be a serious dietary source of Pb and Cd exposure to the consumer population.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Oryza/química , Poluentes do Solo/análise , China , Produtos Agrícolas , Exposição Dietética/estatística & dados numéricos , Ecologia , Humanos , Irã (Geográfico) , Medição de Risco , Fatores de Risco , Rios
6.
Food Chem Toxicol ; 131: 110640, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31233871

RESUMO

Twenty-seven samples of infant formulae and follow-on formulae and fifteen samples of baby food from Iranian markets were analyzed for concentrations of four polycyclic aromatic hydrocarbons (PAH4) determined by use of gas chromatography coupled to mass spectrophotometry. An assessment of risks posed to infants and toddlers was conducted by calculating the margin of exposure and incremental lifetime cancer risk (ILCR) by use of the Monte Carlo Simulation Method. Benzo (a) anthracene, was not detected in any of the samples, while approximately 64.3% samples contained detectable amounts of benzo (a) pyrene, while chrysene was observed in three samples and benzo (b) fluoranthene was detected in one sample. One of the samples contained 1.43 µg PAH4/kg, which was greater than the maximum tolerable limit (MTL; 1 µg/kg) stated in Commission Regulation (EU) 2015/1125. Accordingly, the 95% ILCRs in the infants/toddlers due to ingestion of milk powder and baby foods were determined to be 1.3 × 10-6 and 7.3 × 10-7, respectively. Also, the 95th centiles of the MOEs, due to ingesting milk powder or baby foods by infants/toddlers were estimated to be 3.6 × 104 and 7.2 × 104, respectively. In Iran, infants and toddlers are not at serious health risk (MOE ≥ 1 × 104 and ILCR < 1 × 10-4).


Assuntos
Carcinógenos/análise , Contaminação de Alimentos/análise , Fórmulas Infantis/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Calibragem , Humanos , Lactente , Recém-Nascido , Irã (Geográfico) , Método de Monte Carlo , Medição de Risco
7.
Physiol Mol Biol Plants ; 24(6): 1103-1115, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30425427

RESUMO

Effect of silicon (Si) on the response of strawberry (Fragaria × ananassa var. Parus) plants to arbuscular mycorrhizal fungus (AMF) was studied under growth chamber conditions. Plants were grown in perlite irrigated with nutrient solution without (- Si) or with (+ Si) 3 mmol L-1 Si (~ 84 mg L-1 Si as Na2SiO3) in the absence (- AMF) or presence (+ AMF) of fungus. Dry matter production, root colonization rate, photosynthesis rate and water relation parameters were all improved by both Si and AMF, and the highest amounts were achieved by + Si + AMF treatment. Mycorrhizal effectiveness increased by Si treatment associated with higher Si concentration in the + AMF plants. Leaf concentrations of total soluble and cell wall-bound phenolics were increased by Si accompanied by the enhanced activity of phenylalanine ammonia lyase, but not polyphenol oxidase. Profile of phenolics compound revealed that gallic acid, caffeic acid, epicatechin, chlorogenic acid, ellagic acid and kaempferol increased by both Si and AMF treatments, while p-coumaric acid decreased. In addition to vegetative growth, both treatments improved fruit yield and its quality parameters. Our results showed that Si and AMF acted in a synergistic manner and improved growth and biochemical parameters in strawberry plants. However, the mechanism for Si-mediated increase of mycorrhizal effectiveness is not known, thereby needing further elucidation.

8.
J Sep Sci ; 37(18): 2566-73, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24975571

RESUMO

In this research, magnetic graphene nanoparticles were prepared and used as adsorbents for preconcentrating the aflatoxins in rice, wheat, and sesame samples. For this purpose, graphene was synthesized by Hummer's method. Magnetically modified graphene formed by the deposition of magnetite (Fe3O4) on graphene was used for the separation of aflatoxins B1, B2, G1, and G2 from the samples. The extractants were subsequently analyzed with high-performance liquid chromatography and fluorescence detection. Parameters affecting the efficiency of the method were thoroughly investigated. The measurements were done under the optimized conditions. For aflatoxins B1, B2, G1, and G2, limits of detection were 0.025, 0.05, 0.05, and 0.075 ng/g and limits of quantification were 0.083, 0.16, 0.16, and 0.23 ng/g, respectively. Accuracy was examined by the determination of the relative recovery of the aflatoxins. The relative recovery of aflatoxins B1, B2, G1, and G2 were quite satisfactory (between 64.38 and 122.21% for food samples). Relative standard deviations for within laboratory repeatability (n = 6) were in the range from 1.3 to 3.2. The application of this sorbent for the separation and concentration of the mentioned aflatoxins from food samples was examined.


Assuntos
Aflatoxinas/isolamento & purificação , Análise de Alimentos , Contaminação de Alimentos/análise , Grafite/química , Técnicas de Imunoadsorção , Nanopartículas de Magnetita/química , Adsorção , Aflatoxinas/química , Cromatografia Líquida de Alta Pressão/instrumentação , Técnicas de Imunoadsorção/instrumentação , Oryza/química , Tamanho da Partícula , Sesamum/química , Soluções , Propriedades de Superfície , Triticum/química
9.
Mycotoxin Res ; 28(4): 237-42, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23606195

RESUMO

Forty samples of dried vine fruit (raisin, n = 22; currant, n = 18) were collected in 2009-2011 from the Iranian market. Aflatoxins (AFs) and ochratoxin A (OTA) were determined in these samples after immunoaffinity column clean-up by high performance liquid chromatography (HPLC) with fluorescence detection. The limit of quantification (LOQ) for AFs B1. B2, G1, G2, and OTA were 0.62, 0.50, 0.70, 0.40, and 0.42 ng/g, respectively. AFB1 was found in one sample of raisin (0.64 ng/g) and in two samples of currant (0.20 and 0.63 ng/g). AFB2 (0.33 ng/g) and AFG2 (0.49 ng/g) were found in 2 samples of currant. OTA was detected in 3 of the 22 samples of raisin (mean 2.21 ng/g) and in one sample of currant (2.99 ng/g). The results show that in AFs and OTA levels are well below the regulatory limits both of the European Union and of Iran.


Assuntos
Aflatoxinas/análise , Contaminação de Alimentos/análise , Frutas/química , Ocratoxinas/análise , Ribes/química , Vitis/química , Calibragem , Cromatografia Líquida de Alta Pressão , Comércio , Humanos , Irã (Geográfico) , Limite de Detecção , Padrões de Referência
10.
Artigo em Inglês | MEDLINE | ID: mdl-24779786

RESUMO

The aflatoxins content of 140 cotton seed samples were determined using high-performance liquid chromatography. Samples were obtained from wholesalers in Iran between May 2010 and June 2011. Aflatoxin B1 gave the highest incidence of contamination and was found in 129 of the 139 samples. The highest concentration of aflatoxin was 14.4 ng g⁻¹. Thirteen cotton seed samples (9.35%) were above one of the regulatory limits of the European Union (5 ng g⁻¹), but no sample was above the highest EU limit and the safety limit recommended by the FDA (20 ng g⁻¹) and regulatory limits of Iran (50 ng g⁻¹) for total aflatoxin.


Assuntos
Aflatoxinas/análise , Carcinógenos/análise , Produtos Agrícolas/química , Inspeção de Alimentos/métodos , Gossypium/química , Sementes/química , Aflatoxina B1/análise , Aflatoxina B1/isolamento & purificação , Aflatoxina B1/metabolismo , Aflatoxinas/isolamento & purificação , Aflatoxinas/metabolismo , Métodos Analíticos de Preparação de Amostras , Ração Animal/análise , Ração Animal/economia , Ração Animal/microbiologia , Aspergillus/metabolismo , Automação Laboratorial , Calibragem , Carcinógenos/isolamento & purificação , Carcinógenos/metabolismo , Cromatografia Líquida de Alta Pressão , Produtos Agrícolas/microbiologia , Contaminação de Alimentos , Gossypium/microbiologia , Irã (Geográfico) , Limite de Detecção , Processos Fotoquímicos , Sementes/microbiologia , Espectrometria de Fluorescência
11.
Bull Environ Contam Toxicol ; 88(3): 391-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22109516

RESUMO

Forty five dried fruits, 30 dried apricots and 15 prunes were tested for aflatoxins and ochratoxin A contamination utilizing immunoaffinity column clean up and high performance liquid chromatography (HPLC) with fluorescence detection. 30% and 3.33% of examined apricot samples and 13.33% and 20% of examined prunes samples contained aflatoxin B(1) and ochratoxin A more than 0.2 ng g(-1). The average recoveries were found to be 91.1% and 98.5% for aflatoxin B(1) and ochratoxin A, respectively, while the detection limit was 0.2 ng g(-1) for both mycotoxins.


Assuntos
Aflatoxinas/análise , Contaminação de Alimentos/estatística & dados numéricos , Frutas/química , Ocratoxinas/análise , Monitoramento Ambiental , Análise de Alimentos , Contaminação de Alimentos/análise , Humanos , Irã (Geográfico) , Medição de Risco
12.
Bull Environ Contam Toxicol ; 87(2): 194-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21611739

RESUMO

A study was undertaken to determine levels of aflatoxins and ochratoxin A in bean, using a technique preceded by an immunoaffinity clean-up step. For this purpose, a total of 30 bean samples were analyzed. 16.67% and 10% of examined bean samples contained Aflatoxin B(1) and ochratoxin A more than 0.2 ng g(-1). Recoveries were found to be 91.1% and 98.5% for Aflatoxin B(1) and ochratoxin A, respectively, while the detection limit was 0.2 ng g(-1) for both mycotoxins.


Assuntos
Aflatoxinas/análise , Carcinógenos Ambientais/análise , Contaminação de Alimentos/análise , Ocratoxinas/análise , Phaseolus/química , Aspergillus/metabolismo , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Irã (Geográfico) , Limite de Detecção , Penicillium/metabolismo , Phaseolus/microbiologia
13.
Mycotoxin Res ; 27(4): 259-63, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23605927

RESUMO

A study of the occurrence of aflatoxins (AF) in sesame seeds was conducted in the Khorasan province of Iran between September 2009 and August 2010. Samples (n = 182) were analyzed by liquid chromatography (LC), and detection limits for AFB1, AFB2, AFG1 and AFG2, were 0.45, 0.19, 0.61, and 0.22 ng/g, respectively. AFB1 was detected in 33 samples (18.1%), at a mean level of 1.62 ± 1.32 ng/g, and a maximum level of 5.54 ng/g. AFB1 levels exceeded the European Union (EU) maximum tolerated level (MTL, 2 ng/g) in 9 samples, and the Iran MTL (5 ng/g) in 1 sample. Regarding total aflatoxins (AFT), the mean level was 0.92 ± 1.36 ng/g, and the maximum level was 5.54 ng/g. No sesame sample exceeded the Iran MTL (15 ng/g), but two samples exceeded the EU MTL (4 ng/g) for AFT. It is concluded that low levels of AFs occur frequently in sesame from Iran.

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