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1.
Pan Afr Med J ; 40: 45, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34795826

RESUMO

INTRODUCTION: neffa, a form of air-dried smokeless tobacco used in North Africa, is spuriously perceived as a lower risk alternative to smoking. The objective of this study was to provide information on some harmful constituents of neffa and to use them for cancer risk assessment. METHODS: a high-performance liquid chromatography method coupled with fluorescence detector was used to determine polycyclic aromatic hydrocarbons (PAHs) in one sample of neffa. An atomic absorption spectrometry was performed to determine the concentrations of lead and cadmium in three samples of neffa. The levels of toxicants found in neffa were used to assess for lifetime cancer risk as advocated by the US Environment Protection Agency. RESULTS: the determination of PAHs in neffa allowed the identification of phenanthrene and anthracene. However, the higher molecular weight PAHs such as Benzo(a)Pyrene B(a)P were not detected. The concentrations of cadmium and lead varied between 1.3 to 2.8µg/g and 1.7 to 4.6µg/g respectively. Cancer risk for cadmium and lead varied between 4.2E-03 to 9.3E-03 and 2.5E-06 to 6.4E-06 respectively. Cancer risk for Cd exceeded the range of 10E-04 to 10E-06 of an acceptable risk. CONCLUSION: neffa is not a healthy alternative for overcoming smoking addiction. It contains mineral and organic pulmonary toxicants. This study could serve as a scientific basis to inform consumers about the products´ toxicity and help them to quit smokeless tobacco (SLT) use.


Assuntos
Neoplasias/etiologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Tabaco sem Fumaça/análise , Cádmio/análise , Carcinógenos/análise , Carcinógenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Humanos , Chumbo/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Medição de Risco , Espectrofotometria Atômica , Uso de Tabaco/efeitos adversos , Tabaco sem Fumaça/efeitos adversos , Tunísia
2.
Toxins (Basel) ; 13(6)2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071244

RESUMO

Alkenylbenzenes are potentially toxic (genotoxic and carcinogenic) compounds present in plants such as basil, tarragon, anise star and lemongrass. These plants are found in various edible consumer products, e.g., popularly used to flavour food. Thus, there are concerns about the possible health consequences upon increased exposure to alkenylbenzenes especially due to food intake. It is therefore important to constantly monitor the amounts of alkenylbenzenes in our food chain. A major challenge in the determination of alkenylbenzenes in foods is the complexity of the sample matrices and the typically low amounts of alkenylbenzenes present. This review will therefore discuss the background and importance of analytical separation methods from papers reported from 2010 to 2020 for the determination of alkenylbenzenes in foods and related products. The separation techniques commonly used were gas and liquid chromatography (LC). The sample preparation techniques used in conjunction with the separation techniques were various variants of extraction (solvent extraction, liquid-liquid extraction, liquid-phase microextraction, solid phase extraction) and distillation (steam and hydro-). Detection was by flame ionisation and mass spectrometry (MS) in gas chromatography (GC) while in liquid chromatography was mainly by spectrophotometry.


Assuntos
Benzeno/isolamento & purificação , Carcinógenos/isolamento & purificação , Análise de Alimentos , Mutagênicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Líquida , Extração Líquido-Líquido , Extração em Fase Sólida
3.
Food Chem ; 345: 128863, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33340893

RESUMO

In vitro experiments were conducted to evaluate the effectiveness of two new biosorbents (lettuce and field horsetail) in removing aflatoxin B1 (AFB1). Formosa firethorn was used as reference material. The adsorption of AFB1 (190 ng/mL) was investigated at two sorbent contents (0.5% and 0.1% w/v) and three pHs (2, 5, and 7). Batch experiments were performed at 40 °C for 2 h. Several methodologies were used to characterize the nature of the biosorbent-AFB1 interaction. In general, when using biosorbents at 0.5% w/v, AFB1 was well adsorbed by the three tested biomaterials (70 to 100%). Furthermore, with the lowest biosorbent content (0.1% w/v), significant AFB1 adsorption efficiencies were attained at pH 5 (33 to 50%). Nevertheless, at pH 7, lettuce showed the highest ability against AFB1 removal (95%). Further characterization of the AFB1-loaded biosorbents demonstrated that chemical and physical mechanisms were involved in the adsorption process.


Assuntos
Aflatoxina B1/química , Aflatoxina B1/isolamento & purificação , Carcinógenos/química , Carcinógenos/isolamento & purificação , Equisetum/química , /química , Adsorção , Biodegradação Ambiental , Contaminação de Alimentos/análise
4.
Prep Biochem Biotechnol ; 50(8): 842-848, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302260

RESUMO

Chromium, ranking the second most among toxic heavy metal pollutants in the world, causing respiratory, cardiovascular and renal problems in human beings is under study herein. We examined the biological remediation of the carcinogenic Cr (VI) polluted soils by indigenous yeast isolates. The total element analysis of the treated sample was determined by Energy Dispersion X-ray Micro Analysis (EDXMA). The sample under study was observed to have a high concentration of 458.29 mgKg-1 Cr (VI), determined by Atomic Absorption Spectroscopy (AAS) and DPC analysis. The most tolerant isolate designated as CSR was used for in vitro and ex-situ bioremediation studies of Cr (VI). The isolate achieved significant bioremediation of 86% in vitro and 75.12% in ex-situ method. The optimal conditions for in vitro bioremediation were found to be 28 °C and a pH of 6. The ITS1, 5.8S rRNA and D1, D2 domain of LSU rRNA gene characterization of the isolate CSR illustrated that it belongs to Ustilago genera. The isolate was deposited in NCBI GenBank as Ustilago sp. CSR (KY284846). Although, Ustilago is generally a pathogenic fungus, our study opens up the scope of using Ustilago spp. for bioremediation of the carcinogenic heavy metal Chromium.


Assuntos
Carcinógenos/isolamento & purificação , Cromo/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Leveduras/metabolismo , Biodegradação Ambiental , Carcinógenos/metabolismo , Cromo/metabolismo , Humanos , Microbiologia do Solo , Poluentes do Solo/metabolismo , Leveduras/isolamento & purificação
5.
Sci Rep ; 10(1): 5214, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32251326

RESUMO

In the present work, a method based on solvent extraction and gas chromatography-mass spectrometry (GC-MS) has been validated for the determination of 1,4-dioxane in cosmetics. Various solvents including ethyl acetate, hexane, methanol, dichloromethane and acetone have been used for the extraction of 1,4-dioxane, among them the ethyl acetate was found to be the most efficient extracting solvent. This method has offered excellent quality parameters for instance linearity (R2 > 0.9991), limit of detection (LOD, 0.00065-0.00091 µg/mL), limit of quantification (LOQ, 0.00217-0.00304 µg/mL) and, precision intra-day (1.65-2.60%, n = 5) and inter-day (0.16-0.32%, n = 5) in terms of relative standard deviation (RSD%). A total of thirty-nine cosmetic samples of different brands and origin have been studied. Among them, the 1,4-dioxane was found in twenty-three samples (FB1-FB7, MC1-MC4, MC6-MC8, HS3, HS5, BL1-BL3, BL5 and PLD1-PLD3) at the levels between 0.15 µg/mL and 9.92 µg/mL, whereas in sixteen samples (MC5, HS1, HS2, SG1-SG5, BL4 and HP1- HP6) was found to be not detected. The recovery values were achieved between 93% and 99% in both low and high level of spiked samples. In comparison to the traditional analytical techniques, the proposed method was found to be very sensitive and cost-effective for the routine analysis of 1,4-dioxane at low concentration in cosmetics.


Assuntos
Carcinógenos/análise , Cosméticos/análise , Dioxanos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Acetatos , Carcinógenos/isolamento & purificação , Análise Custo-Benefício , Dioxanos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/economia , Arábia Saudita , Solventes
6.
J Hazard Mater ; 384: 121261, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31574386

RESUMO

Carcinogenic GenX chemicals, heptafluoropropylene-oxide-dimer-acid (HFPO-DA), have been recently detected in surface, ground and recycled water sources worldwide. However, GenX removals under the influence of variable characteristics of the organic and inorganic compounds present in the natural water sources, have often been overlooked in scientific literature. This is critically important given that the ionic composition and characteristics of organic matter in natural waters are spatially and seasonally variable. A strongly basic anion exchange (IX) resin was used to remove GenX and two other perfluorinated ether acids (PFEAS) from natural surface and recycled water sources. Factors influencing the uptake behavior included the PFEAS concentrations, resin dosage, and background anion characteristics. The equivalent background compound was employed to evaluate the competitive uptake between natural organic matter (NOM), inorganic ions and PFEAS in natural water matrices. Experimental data were compared with different mathematical and physical models and it was depicted that approximately 4-6% of the initial NOM competed with PFEAS for active exchange sites. Further, IX was able to achieve complete PFEAS removal (Cfinal<10 ng/L) with simultaneous removal of>60% NOM and >80% inorganic ions. Results of this study indicate that IX exhibits great potential for PFEAS removal from natural drinking water sources.


Assuntos
Resinas de Troca Aniônica/química , Carcinógenos/isolamento & purificação , Fluorocarbonos/isolamento & purificação , Propionatos/isolamento & purificação , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Água Potável/química , Águas Residuárias/química
7.
J Chromatogr A ; 1608: 460424, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31416626

RESUMO

Aristolochic acid (AA) I and AA II, which have been classified as carcinogenic to human and have been proven to be nephrotoxic, are bioactive ingredients of many traditional Chinese medicines (TCMs). Thus, development of an efficient approach for separation and determination of AA I and AA II in biological samples and herbal plants is of significance. Herein, electromembrane extraction (EME) was for the first time used to separate AA I and AA II. It is noted that also for the first time 1-decanol was discovered and used as an efficient SLM solvent for EME of acidic compounds. The proposed EME system was used to extract AA I and AA II from urine samples (recovery≥68%). The approach of EME combined with LC-MS (EME-LC/MS) was evaluated using urine samples. The linear range for AA I and AA II was 10-1000 ng mL-1 (R2≥0.9970), and the limits of detection (LOD, S/N = 3) for AA I and AA II were 2.7 and 2.9 ng mL-1, respectively. Finally, this EME-LC/MS approach was employed to discover AA I and AA II in the herbal plants. In addition, using standard addition method, AA I in Aristolochicaceae-Liao Asarum (ALA) and Radix Aristolochice (RA) were 0.23 and 2044.13 µg g-1, and AA II in ALA and RA were 0 and 338.48 µg g-1, respectively. The repeatability of EME-LC/MS at all cases for both urine samples and herbal plants was below 15% (RSD-value). We believe that EME would be a useful tool to isolate bioactive ingredients of TCMs from complex samples for different purposes.


Assuntos
Ácidos Aristolóquicos/isolamento & purificação , Carcinógenos/isolamento & purificação , Técnicas Eletroquímicas/métodos , Ácidos Aristolóquicos/análise , Carcinógenos/análise , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Técnicas Eletroquímicas/instrumentação , Humanos , Espectrometria de Massas , Medicina Tradicional Chinesa
8.
J Sci Food Agric ; 99(9): 4452-4459, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30866048

RESUMO

BACKGROUND: Diethylstilbestrol (DES) residues are harmful to human health because of their potential carcinogenic properties. Therefore, it is important to develop a fast and efficient pretreatment method to prevent their harmful effects on human health and the environment. RESULTS: In this paper, two types of magnetic molecularly imprinted polymers (MMIPs) of DES were prepared by bulk polymerization and the sol-gel method, respectively. The synthetic materials were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis. Adsorption capacities of the bulk and sol-gel MMIPs were investigated. A rapid detection method was developed using the two types of MMIPs as sorbents, coupled to high-performance liquid chromatography, for the determination of DES residues in milk samples. Under optimized conditions, the limit of detection (S/N = 3) of both methods for DES was 2.0 µg L-1 ; and the linear response range to DES was 0.1-500 mg L-1 . The milk samples were analyzed according to this method with good recoveries of 88.3-97.6 and 90.5-103.5% for the two types of MMIPs, respectively. CONCLUSIONS: The method described had high sensitivity and high selectivity, and could prove to be a new method for the rapid determination of DES residues in milk samples. © 2019 Society of Chemical Industry.


Assuntos
Carcinógenos/isolamento & purificação , Dietilestilbestrol/isolamento & purificação , Magnetismo/métodos , Leite/química , Polímeros/química , Extração em Fase Sólida/métodos , Adsorção , Animais , Carcinógenos/análise , Bovinos , Cromatografia Líquida de Alta Pressão , Dietilestilbestrol/análise , Contaminação de Alimentos/análise , Impressão Molecular , Polímeros/síntese química , Sensibilidade e Especificidade , Extração em Fase Sólida/instrumentação
9.
J Chromatogr A ; 1595: 207-214, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-30827697

RESUMO

4-(methylintrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) are the most prevalent and toxic tobacco specific nitrosamines (TSNAs). Due to their carcinogenicity, knowledge of the composition of NNK and NNN in tobacco is necessary. Herein, a sensitive and rapid method, which employs autoclave extraction-supercritical fluid chromatography/tandem mass spectrometry (SFC-MS/MS), has been developed for the analysis of NNK and NNN in tobacco. Both water-soluble and matrix-bound NNK and NNN were extracted with 100 mM ammonium acetate in an autoclave (130 °C, 4 h), and the aqueous extract was subjected to solvent replacement prior to SFC-MS/MS analysis. NNK and NNN were effectively separated within 5 min by using supercritical CO2 as the main mobile phase coupled with a co-solvent of methanol. Excellent linearity was obtained with coefficients of determination (R2) greater than 0.9997 in the range of 1-160 ng/mL and 5-800 ng/mL for NNK and NNN, respectively. The recoveries were in the range of 92.5-110.0% at different spiked levels of real samples. 12 tobacco samples which include 3 typical tobacco varieties of burley, flue-cured, and oriental tobaccos had been analyzed, and the fraction of matrix-bound NNK was determined as well. In addition, a comparison between the proposed SFC-MS/MS method and a validated liquid chromatography tandem mass spectrometry (LC-MS/MS) internal standard method was conducted. Both techniques exhibit comparable analysis results, but peak splitting of NNN was observed by LC-MSMS due to the existence of E/Z isomers, while SFC-MS/MS offers great improvement through elution condition optimization, demonstrating the applicability of SFC-MS/MS as an alternative tool for NNK and NNN analysis.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia com Fluido Supercrítico , Nitrosaminas/isolamento & purificação , Espectrometria de Massas em Tandem , Carcinógenos/análise , Carcinógenos/isolamento & purificação , Nitrosaminas/análise
10.
Mini Rev Med Chem ; 19(15): 1196-1203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30887924

RESUMO

Cancer is the second leading factor of human death in the world. Long-term consumption of cooked red meat brings about various types of cancers like colorectal cancer due to the formation of Heterocyclic Aromatic Amines (HAAs) during the heating process of meat. There are various solutions for the reduction of these toxicants. The aim of this article is to describe probiotic as one of the possible strategies for bioremoval of these carcinogenic and mutagenic substances and change food to functional one as well. The mechanism of biodetoxification is binding by probiotics, which depends on some variables including the probiotic characteristics, kind and content of the mutagens, as well as some properties of media. In this article, after introducing detoxification ability of probiotics and listing of all reported probiotics in this field, the influencing variables are surveyed and finally, opportunities and problems of HAA bioremoval by probiotics are described.


Assuntos
Aminas/química , Carcinógenos/química , Compostos Heterocíclicos/química , Mutagênicos/química , Neoplasias/prevenção & controle , Probióticos/farmacologia , Desintoxicação por Sorção/métodos , Aminas/efeitos adversos , Aminas/síntese química , Aminas/isolamento & purificação , Carcinógenos/síntese química , Carcinógenos/isolamento & purificação , Compostos Heterocíclicos/efeitos adversos , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/isolamento & purificação , Humanos , Carne/efeitos adversos , Mutagênicos/efeitos adversos , Mutagênicos/síntese química , Mutagênicos/isolamento & purificação , Neoplasias/dietoterapia , Neoplasias/etiologia , Probióticos/química
11.
Food Chem ; 269: 503-510, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100466

RESUMO

The presence of carcinogens in food is a major food safety concern. A nanocomposite-based electrochemical DNA biosensor was constructed for potential carcinogen detection in food samples by immobilizing amine terminated single stranded DNA onto silica nanospheres deposited onto a screen-printed electrode modified using gold nanoparticles. The effect of three different DNA sequences: 15-base guanine, 24-base guanine and 24-base adenine-thymine rich DNA on carcinogen (formaldehyde and acrylamide) detection was evaluated. The competitive binding of the DNA with the carcinogen and electroactive indicator, Methylene blue (MB) was measured using differential pulse voltammetry. Optimization studies were conducted for MB concentration and accumulation time, DNA concentration, buffer concentration, pH and ionic strength. Overall, the 24-base guanine rich DNA yielded the best results with a detection limit of 0.0001 ppm, linear range between 0.0001 ppm and 0.1 ppm and reproducibility below 5% R.S.D. Finally, the results obtained using the biosensor were validated using Ames test.


Assuntos
Técnicas Biossensoriais/métodos , Carcinógenos/isolamento & purificação , DNA/análise , Análise de Alimentos/métodos , Ouro , Nanopartículas Metálicas , Reprodutibilidade dos Testes
12.
J Cosmet Sci ; 69(2): 145-156, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29799811

RESUMO

Safrole is a well-known carcinogenic agent that is present in camphor trees. In this study, a gas chromatographic method was established to quantitate the levels of safrole in essential oils using n-decyl alcohol as an internal standard. The method used a nonpolar column and was able to detect concentrations of safrole as low as 5 µg/ml in the samples. Following addition of 2-10 mg of safrole into 1 g of essential oil extracted from Stout Camphor wood (Cinnamomum kanehirai Hayata) or 1-10 mg of safrole into 1 g of essential oil extracted from Small-flower Camphor wood (Cinnamomum micranthum Hayat), the recovery rates of safrole were determined. With direct injection of samples into the gas chromatograph, the results showed that the recovery was more than 96.1%, with a coefficient of variation below 5.6%. We then analyzed 23 commercially available Stout Camphor and other essential oil samples and found that 21 of them contained safrole in the range of 37.65-355.07 mg/g. In addition, in the heavier essential oil distilled from Small-flower Camphor wood, the safrole level was up to 642.98 mg/g. Our results demonstrated that most camphor essential oils on the market have a carcinogenic potential due to their high safrole levels.


Assuntos
Cânfora/química , Carcinógenos/isolamento & purificação , Cromatografia Gasosa/métodos , Óleos Voláteis/química , Safrol/isolamento & purificação , Carcinógenos/química , Cinnamomum/química , Safrol/análise
13.
Sci Rep ; 8(1): 2476, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29410452

RESUMO

Cancer incidence appears to be higher amongst firefighters compared to the general population. Given that many cancers have an environmental component, their occupational exposure to products of carbon combustion such as polycyclic aromatic hydrocarbons (PAHs) is of concern. This is the first UK study identifying firefighters exposure to PAH carcinogens. Wipe samples were collected from skin (jaw, neck, hands), personal protective equipment of firefighters, and work environment (offices, fire stations and engines) in two UK Fire and Rescue Service Stations. Levels of 16 US Environmental Protection Agency (EPA) PAHs were quantified together with more potent carcinogens: 7,12-dimethylbenzo[a]anthracene, and 3-methylcholanthrene (3-MCA) (12 months post-initial testing). Cancer slope factors, used to estimate cancer risk, indicate a markedly elevated risk. PAH carcinogens including benzo[a]pyrene (B[a]P), 3-MCA, and 7,12-dimethylbenz[a]anthracene PAHs were determined on body surfaces (e.g., hands, throat), on PPE including helmets and clothing, and on work surfaces. The main exposure route would appear to be via skin absorption. These results suggest an urgent need to monitor exposures to firefighters in their occupational setting and conduct long-term follow-up regarding their health status.


Assuntos
Carcinógenos/toxicidade , Bombeiros , Neoplasias/epidemiologia , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , 9,10-Dimetil-1,2-benzantraceno/isolamento & purificação , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Benzopirenos/isolamento & purificação , Benzopirenos/toxicidade , Carcinógenos/isolamento & purificação , Monitoramento Ambiental , Humanos , Incidência , Metilcolantreno/isolamento & purificação , Metilcolantreno/toxicidade , Neoplasias/etiologia , Neoplasias/prevenção & controle , Doenças Profissionais/etiologia , Doenças Profissionais/prevenção & controle , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Roupa de Proteção , Pele/química , Pele/efeitos dos fármacos , Absorção Cutânea , Reino Unido/epidemiologia
14.
Talanta ; 181: 132-141, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29426492

RESUMO

The predominant enantiomer of nicotine found in nature is (S)-nicotine and its pharmacology has been widely established. However, pharmacologic information concerning individual enantiomers of nicotine-related compounds is limited. Recently, a modified macrocyclic glycopeptide chiral selector was found to be highly stereoselective for most tobacco alkaloids and metabolites. This study examines the semi-synthetic and native known macrocyclic glycopeptides for chiral recognition, separation, and characterization of the largest group of nicotine-related compounds ever reported (tobacco alkaloids, nicotine metabolites and derivatives, and tobacco-specific nitrosamines). The enantioseparation of nicotine is accomplished in less than 20s for example. All liquid chromatography separations are mass spectrometry compatible for the tobacco alkaloids, as well as their metabolites. Ring-closed, cyclized structures were identified and separated from their ring-open, straight chain equilibrium structures. Also, E/Z-tobacco-specific nitrosamines and their enantiomers were directly separated. E/Z isomers also are known to have different physical and chemical properties and biological activities. This study provides optimal separation conditions for the analysis of nicotine-related isomers, which in the past have been reported to be ineffectively separated which can result in inaccurate results. The methodology of this study could be applied to cancer studies, and lead to more information about the role of these isomers in other diseases and as treatment for diseases.


Assuntos
Alcaloides/química , Carcinógenos/química , Nitrosaminas/química , Alcaloides/isolamento & purificação , Alcaloides/metabolismo , Carcinógenos/isolamento & purificação , Carcinógenos/metabolismo , Cromatografia Líquida/métodos , Glicopeptídeos/química , Espectrometria de Massas/métodos , Nicotina/química , Nicotina/isolamento & purificação , Nicotina/metabolismo , Nitrosaminas/isolamento & purificação , Nitrosaminas/metabolismo , Reprodutibilidade dos Testes , Estereoisomerismo
15.
PLoS One ; 12(10): e0185986, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29016677

RESUMO

Ochratoxin A (OTA) is a potent nephrotoxin and carcinogen which is found in a wide variety of common foods and beverages and it is produced by several species of Aspergillus and Penicillium. Ochratoxin α (OTα), a major metabolite of OTA, has also been reported to occur in cultures of OTA-producing species. However there is some controversial about the participation of OTα in the biosynthesis of OTA, mainly because its biosynthesis pathway has not yet been completely characterized. Aspergillus carbonarius is the main responsible source of ochratoxin A (OTA) in food commodities such as wine, grapes or dried vine fruits from main viticultural regions worldwide. However, little is known about the presence of OTα in isolates of A. carbonarius. In this study we evaluated the effects of temperature and incubation time on OTα production by both OTA and non-OTA-producing strains of A. carbonarius. OTA and OTα were detected on the basis of HPLC fluorometric response compared with that of their standards and confirmed by HPLC-MS in selected samples. The non-OTA-producing strains did produce neither OTA nor OTα at any of the conditions tested. The OTA-producing strains studied were able to produce both OTA and OTα in most of the conditions tested. In general, higher amounts of OTA than OTα were produced, but a positive correlation in the production of these two metabolites was detected. The lack of production of both OTA and OTα in the non-OTA-producing strains could be caused by the presence of silent genes or by mutations in functional or regulatory genes involved in OTA production.


Assuntos
Aspergillus/metabolismo , Carcinógenos/metabolismo , Contaminação de Alimentos/análise , Ocratoxinas/biossíntese , Vinho/análise , Aspergillus/crescimento & desenvolvimento , Austrália , Carcinógenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Meios de Cultura/química , Europa (Continente) , Humanos , Israel , Ocratoxinas/isolamento & purificação , Temperatura , Vitis/química , Vitis/microbiologia , Vinho/microbiologia
16.
Toxicon ; 134: 26-29, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28559101

RESUMO

Bovine enzootic haematuria (BEH) is caused by prolonged ingestion of toxic principles of bracken fern, essentially by Pteridium spp. In northwestern Argentina, this disease has a great economic impact ant it is attributed a chronic consumption to Pteridium arachnoideum. This paper describes two endemic areas for enzootic hematuria due to the consumption of Pteris deflexa and Pteris plumula. Two areas where P. deflexa and P. plumula are endemic, but free of Pteridium species, were devised and seven farms were visited. The disease was confirmed based on the presence of clinically affected animals. In four necropsies bleeding neoplastic lesions were observed in the mucosa of the urinary bladder. At phytochemical analysis, both ptaquiloside and pterosin B were found in P. deflexa and P. plumula. Thus, the consumption of P. deflexa and P. plumula can also cause BEH.


Assuntos
Doenças dos Bovinos/etiologia , Hematúria/veterinária , Intoxicação por Plantas/veterinária , Pteris/envenenamento , Animais , Argentina , Carcinógenos/isolamento & purificação , Bovinos , Hematúria/induzido quimicamente , Indanos/isolamento & purificação , Pteris/química , Sesquiterpenos/isolamento & purificação , Neoplasias da Bexiga Urinária/induzido quimicamente
17.
J Chromatogr A ; 1507: 37-44, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28583391

RESUMO

Aromatic amines in mainstream cigarette smoke have long been monitored due to their carcinogenic toxicity. In this work, a reliable and rapid method was developed for the simultaneous determination of 9 aromatic amines in mainstream cigarette smoke by modified dispersive liquid liquid microextraction (DLLME) and ultraperformance convergence chromatography tandem mass spectrometry (UPC2-MS/MS). Briefly, the particulate phase of the cigarette smoke was captured by a Cambridge filter pad, and diluted hydrogen chloride aqueous solution is employed to extract the aromatic amines under mechanical shaking. After alkalization with sodium hydroxide solution, small amount of toluene was introduced to further extract and enrich aromatic amines by modified DLLME under vortexing. After centrifugation, toluene phase was purified by a universal QuEChERS cleanup kit and was finally analyzed by UPC2-MS/MS. Attributing to the superior performance of UPC2-MS/MS, this novel approach allowed the separation and determination of 9 aromatic amines within 5.0min with satisfactory resolution and sensitivity. The proposed method was finally validated using Kentucky reference cigarette 3R4F, and emission levels of targeted aromatic amines determined were comparable to previously reported methods At three different spiked levels, the recoveries of most analytes were ranged from 74.01% to 120.50% with relative standard deviation (RSD) less than 12%, except that the recovery of p-toluidine at low spiked level and 3-aminobiphenyl at medium spiked level was 62.77% and 69.37% respectively. Thus, this work provides a novel alternative method for the simultaneous analysis of 9 aromatic amines in mainstream cigarette smoke.


Assuntos
Aminas/química , Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Líquida/métodos , Fumaça/análise , Espectrometria de Massas em Tandem/métodos , Produtos do Tabaco/análise , Aminas/isolamento & purificação , Carcinógenos/química , Carcinógenos/isolamento & purificação , Estrutura Molecular
18.
J Agric Food Chem ; 65(9): 1992-1999, 2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28215082

RESUMO

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are ubiquitous environmental pollutants attracting increasing attention because of their potent mutagenicity to humans. Previous studies of nitro-PAHs focused on investigating their formation mechanisms and detecting them in atmospheric environment; however, few studies have reported their occurrence in food samples, and regulations on nitro-PAHs are still lacking. We report in this study the development and application of a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for determination of nitro-PAHs in rice and vegetable samples. Analysis of the collected samples by the validated method revealed 1-nitropyrene and 2-nitrofluorene were widespread food contaminants. A comparative study with benzo[a]pyrene, the commonly used marker for PAH exposure, showed that carcinogenic nitro-PAHs existed in rice and vegetables at similar concentrations. Dietary exposure risk, which was estimated based on the surveillance data, suggested 3.28-5.03 ng/kg/day of nitro-PAHs exposure for Hong Kong citizens from rice grains and vegetables.


Assuntos
Carcinógenos/isolamento & purificação , Poluentes Ambientais/isolamento & purificação , Fluorenos/isolamento & purificação , Oryza/química , Pirenos/isolamento & purificação , Verduras/química , Benzo(a)pireno/análise , Benzo(a)pireno/isolamento & purificação , Carcinógenos/análise , Cromatografia Líquida de Alta Pressão , Poluentes Ambientais/análise , Fluorenos/análise , Contaminação de Alimentos/análise , Hong Kong , Pirenos/análise , Sementes/química
19.
Regul Toxicol Pharmacol ; 86: 117-127, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28238852

RESUMO

Carbonyls are harmful and potentially harmful constituents (HPHCs) in mainstream cigarette smoke (MSS). Carbonyls, including formaldehyde and acrolein, are carcinogenic or mutagenic in a dose-dependent manner. Past studies demonstrate significant reduction of HPHCs by charcoal filtration. However, limits of charcoal filtration and cigarette design have not yet been investigated in a systematic manner. Objective data is needed concerning the feasibility of HPHC reduction in combustible filtered cigarettes. This systematic study evaluates the effect of charcoal filtration on carbonyl reduction in MSS. We modified filters of ten popular cigarette products with predetermined quantities (100-400 mg) of charcoal in a plug-space-plug configuration. MSS carbonyls, as well as total particulate matter, tar, nicotine, carbon monoxide (TNCO), and draw resistance were quantified. Significant carbonyl reductions were observed across all cigarette products as charcoal loading increased. At the highest charcoal loadings, carbonyls were reduced by nearly 99%. Tar and nicotine decreased modestly (<20%) compared to reductions in carbonyls. Increased draw resistance was significant at only the highest charcoal loadings. This work addresses information gaps in the science base that can inform the evaluation of charcoal filtration as an available technological adaptation to cigarette design which reduces levels of carbonyls in MSS.


Assuntos
Carcinógenos/isolamento & purificação , Carvão Vegetal , Filtração/instrumentação , Mutagênicos/isolamento & purificação , Fumaça , Produtos do Tabaco , Acroleína/isolamento & purificação , Acroleína/toxicidade , Formaldeído/isolamento & purificação , Formaldeído/toxicidade , Nicotina/análise
20.
J Agric Food Chem ; 65(4): 981-985, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28064506

RESUMO

Acid hydrolyzed vegetable protein (aHVP) is used for flavoring a wide variety of foods and also in the production of nonfermented soy sauce. During the production of aHVP, chloropropanols including 3-monochloropropane-1,2-diol (3-MCPD) and 1,3 dichloropropane-2-ol (1,3-DCP) can be formed through the reaction of the hydrochloric acid catalyst and residual fat and the reaction of 3-MCPD with acetic acid, respectively. 3-MCPD is a carcinogen, and 1,3-DCP has been classified as a genotoxic carcinogen. The European Union (EU) has set a maximum concentration of 0.02 mg/kg of 3-MCPD in aHVP, and the Food and Drug Administration (FDA) set a guidance limit of 1 mg/kg of 3-MCPD in aHVP. 1,3-DCP is not an approved food additive, and the Joint FAO/WHO Expert Committee on Food Additives (JEFCA) has set a limit at 0.005 mg/kg, which is close to the estimated method detection limit. Currently there are few analytical methods for the simultaneous determination of 3-MCPD and 1,3-DCP without derivatization due to differences in their physical chemical properties and reactivity. A new method was developed using QuEChERS (quick, easy, cheap, effective, rugged, and safe) with direct analysis of the extract without derivatization using gas chromatography-triple quadrupole mass spectrometry (GC-QQQ). Additionally, a market sampling of 60 soy sauce samples was performed in 2015 to determine if concentrations have changed since the FDA limit was set in 2008. The sampling results were compared between the new QuEChERS method and a method using phenylboronic acid (PBA) as a derivatizing agent for 3-MCPD analysis. The concentrations of 3-MCPD detected in soy sauce samples collected in 2015 (

Assuntos
Fracionamento Químico/métodos , Aromatizantes/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Propano/análogos & derivados , alfa-Cloridrina/análise , alfa-Cloridrina/isolamento & purificação , Carcinógenos/análise , Carcinógenos/isolamento & purificação , Contaminação de Alimentos/análise , Limite de Detecção , Propano/análise , Propano/isolamento & purificação
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