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1.
Arch Pharm Res ; 47(3): 272-287, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416389

RESUMO

Gymnopilus orientispectabilis, also known as "big laughter mushroom," is a hallucinogenic poisonous mushroom that causes excessive laughter upon ingestion. From the fruiting bodies of G. orientispectabilis, eight lanostane-type triterpenoids (1-8), including seven novel compounds: gymnojunols A-G (2-8), were isolated. The chemical structures of these new compounds (2-8) were determined by analyzing their 1D and 2D NMR spectra and HR-EISMS, and their absolute configurations were unambiguously assigned by quantum chemical ECD calculations and a computational method coupled with a statistical procedure (DP4+). Upon evaluating autophagic activity, compounds 2, 6, and 7 increased LC3B-II levels in HeLa cells to a similar extent as bafilomycin, an autophagy inhibitor. In contrast, compound 8 decreased the levels of both LC3B-I and LC3B-II, and a similar effect was observed following treatment with rapamycin, an autophagy inducer. Our findings provide experimental evidence for new potential autophagy modulators in the hallucinogenic poisonous mushroom G. orientispectabilis.


Assuntos
Agaricales , Venenos , Triterpenos , Humanos , Triterpenos/farmacologia , Triterpenos/química , Venenos/análise , Estrutura Molecular , Células HeLa , Agaricales/química , Carpóforos/química
2.
Food Chem ; 410: 135389, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623457

RESUMO

Poisoning events concerning diarrhetic shellfish poisons (DSPs) are increasing continually. It is extremely necessary to develop simple analysis methods for screening simultaneously different types of DSPs from food-related samples. Okadaic acid (OA) and its analogues, i.e., dinophysistoxin-1 (DTX-1) and dinophysistoxin-2 (DTX-2), are the prevalent DSPs. Herein, a facile and label-free fluorescent aptasensor targeting the three DSPs was constructed with a pair of group-specific split aptamers and silver nanocluster beacon. In presence of the targets, the DNA templates attached at the ends of the split aptamers would be dragged close to trigger enhanced fluorescence signals from silver nanoclusters. The aptasensor offered high sensitivity and good selectivity, with limit of detection of 2.282 nmolL-1, 19.38 nmolL-1, and 13.61 nmolL-1 for OA, DTX-1, and DTX-2, respectively. Moreover, the applicability of aptasensor was well verified with shellfish and seawater samples. This study provides good reference for further exploration on analysis methods for food-related molecules.


Assuntos
Venenos , Intoxicação por Frutos do Mar , Humanos , Toxinas Marinhas/análise , Prata , Piranos/análise , Ácido Okadáico/análise , Frutos do Mar/análise , Venenos/análise
3.
Sci Total Environ ; 822: 153581, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35104517

RESUMO

Wildlife around cities bioaccumulate multiple harmful environmental pollutants associated with human activities. Exposure severity can vary based on foraging behaviour and habitat use, which can be examined to elucidate exposure pathways. Carnivores can play vital roles in ecosystem stability but are particularly vulnerable to bioaccumulation of pollutants. Understanding the spatial and dietary predictors of these contaminants can inform pollutant control, and carnivores, at the top of food webs, can act as useful indicator species. We test for exposure to toxic organochlorines (OCs), including dichloro-diphenyl-trichloroethane (DDT) and polychlorinated biphenyls (PCBs), in a medium-sized felid, the caracal (Caracal caracal), across the peri-urban and agricultural landscapes of the city of Cape Town, South Africa. Concentrations in both blood (n = 69) and adipose tissue (n = 25) were analysed along with detailed spatial, dietary, demographic, and physiological data to assess OC sources and exposure risk. The analysis revealed widespread exposure of Cape Town's caracals to organochlorines: detection rate was 100% for PCBs and 83% for DDTs in blood, and 100% for both compounds in adipose. Caracals using human-transformed areas, such as vineyards and areas with higher human population and electrical transformer density, as well as wetland areas, had higher organochlorine burdens. These landscapes were also highly selected foraging areas, suggesting caracals are drawn into areas that co-incidentally increase their risk of exposure to these pollutants. Further, biomagnification potential was higher in individuals feeding on higher trophic level prey and on exotic prey. These findings point to bioaccumulation of OC toxicants and widespread exposure across local food webs. Additionally, we report possible physiological effects of exposure, including elevated white blood cell and platelet count, suggesting a degree of immunological response that may increase disease susceptibility. Cape Town's urban fringes likely represent a source of toxic chemicals for wildlife and require focused attention and action to ensure persistence of this adaptable mesocarnivore.


Assuntos
Hidrocarbonetos Clorados , Venenos , Bifenilos Policlorados , Animais , Ecossistema , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/análise , Poluentes Orgânicos Persistentes , Venenos/análise , Bifenilos Policlorados/análise , África do Sul
4.
Biol Trace Elem Res ; 200(11): 4846-4854, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35031964

RESUMO

Concentrations of Cd, Hg, Pb, As, Al, Cu, Fe, and Zn were determined in the muscles of wild and farmed European seabass in Sinop markets between September and December in 2020, using inductively coupled plasma mass spectrometry after microwave digestion. In the study, iron (Fe), zinc (Zn), aluminum (Al), and copper (Cu) were found higher than the other metals both in wild and cultured Dicentrarchus labrax. These are essential elements, but excess amounts act as a poison. Arsenic (As) concentration was higher than cadmium (Cd), mercury (Hg), and lead (Pb) both in wild and cultured D. labrax. The estimated maximum total dietary intakes of these eight metals from both wild and farmed European seabass were below the maximum acceptable daily intake values set by the Turkish Food Codex and European Union Regulation. Results showed that according to metal amounts, consumption of D. labrax had no threat to consumers' health. The target hazard quotient (THQ) revealed that harmful health impacts may not occur. Furthermore, risk index (RI) indicated that there may have a lower risk of developing cancer in the future who have been exposed to Pb and As through fish intake. Although the fish are not overly contaminated, the metal level is rising. Increased amounts of heavy metals in fish in different areas could be due to an increase in farm inflow water, domestic sewage, and a number of other anthropogenic sources, all of which should be looked into further. Precautions should be made to safeguard this fish from metal contamination and to reduce the risk to human health.


Assuntos
Arsênio , Bass , Mercúrio , Metais Pesados , Venenos , Poluentes Químicos da Água , Alumínio/análise , Animais , Arsênio/análise , Cádmio/análise , Cobre/análise , Monitoramento Ambiental/métodos , Humanos , Ferro/análise , Chumbo/análise , Mercúrio/análise , Metais Pesados/análise , Venenos/análise , Medição de Risco , Esgotos , Água/análise , Poluentes Químicos da Água/análise , Zinco/análise
5.
J Forensic Sci ; 67(3): 1312-1319, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35005788

RESUMO

The incidence of paraquat poisoning has significantly decreased with the addition of odorizer and emetics to the liquid concentrate. Paraquat poisonings are usually attributed to suicidal and accidental or occupational exposure. Here, we report an unusual fatal case of homicidal paraquat poisoning. An intoxicated, a 37-year-old man consumed a mixture of white wine and paraquat prepared by his wife. This resulted in intermittent vomiting, which he attributed to being intoxicated. The man was admitted to the hospital for treatment 3 days later. Due to the lack of knowledge of paraquat exposure, the man did not receive effective treatment and died of respiratory failure 22 days later. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was applied to detect paraquat in 16 postmortem specimens: kidney (1.31 ug/g), urine (0.91 ug/ml), liver (0.62 ug/g), lung (0.39 ug/g), muscle (0.35 ug/g), bile (0.32 ug/ml), heart (0.28 ug/g), brain (0.22 ug/g), pancreas (0.22 ug/g), spleen (0.18 ug/g), cardiac blood (0.15 ug/ml), cerebrospinal fluid (0.14 ug/ml), pericardial effusion (0.12 ug/ml), pleural effusion (0.09 ug/ml), peripheral blood (0.08 ug/ml), and vitreous humor (0.06 ug/ml). The highest concentration of paraquat was detected in the kidney followed by the urine in all tissues and body fluids. At present, although the cases of paraquat poisoning have decreased, the high mortality rate resulting from its irreversible lung damage and respiratory failure makes paraquat poisoning, especially occult paraquat poisoning, still needs to be carefully identified in forensic practice and clinical diagnosis.


Assuntos
Intoxicação , Venenos , Insuficiência Respiratória , Adulto , Humanos , Fígado/química , Masculino , Paraquat/análise , Venenos/análise , Espectrometria de Massas em Tandem
6.
Toxins (Basel) ; 13(11)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34822566

RESUMO

Enzyme-linked immunosorbent assay (ELISA) is widely used in the routine screening of mycotoxin contamination in various agricultural and food products. Herein, a cascade-amplifying system was introduced to dramatically promote the sensitivity of an immunoassay for ochratoxin A (OTA) detection. Specifically, a biotinylated M13 bacteriophage was introduced as a biofunctional competing antigen, in which a seven-peptide OTA mimotope fused on the p3 protein of M13 was used to specifically recognize an anti-OTA monoclonal antibody, and the biotin molecules modified on capsid p8 proteins were used in loading numerous streptavidin-labeled polymeric horseradish peroxidases (HRPs). Owing to the abundance of biotinylated p8 proteins in M13 and the high molar ratio between HRP and streptavidin in streptavidin-polyHRP, the loading amount of HRP enzymes on the M13 bacteriophage were greatly boosted. Hence, the proposed method exhibited high sensitivity, with a limit of detection of 2.0 pg/mL for OTA detection, which was 250-fold lower than that of conventional ELISA. In addition, the proposed method showed a slight cross-reaction of 2.3% to OTB, a negligible cross-reaction for other common mycotoxins, and an acceptable accuracy for OTA quantitative detection in real corn samples. The practicability of the method was further confirmed with a traditional HRP-based ELISA method. In conclusion, the biotinylated bacteriophage and polyHRP structure showed potential as a cascade-amplifying enzyme loading system for ultra-trace OTA detemination, and its application can be extended to the detection of other analytes by altering specific mimic peptide sequences.


Assuntos
Imunoensaio/métodos , Ocratoxinas/análise , Venenos/análise , Bacteriófagos/química , Biotinilação
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 259: 119883, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33971441

RESUMO

The sensitive detection and identification of toxicants in oily matrices have suffered from difficulty in poisoning incidents, therefore it is necessary to develop the rapid and efficient analytical method to realize the on-site screening and analyzing. In this report, the surface-enhanced Raman spectroscopy (SERS) method was used to detect paraquat and diquat poisons in various oily matrix coupled with solvent extraction. The solvent extraction not only remove interfering impurities of oily substrates, but also can enrich and separate the poisons from oily matrix. It was demonstrated that the ethanol as the extractant was suitable for the rapid separation of poisons such as paraquat (PQ) and diquat (DQ) in oily matrix (soy sauce, pasta sauce, sesame oil, chili oil). Moreover, combined with a handheld Raman spectrometer, the entire detection process was completed within 8 min with the level of 10 ppb PQ and 100 ppb DQ. Furthermore, double-blind experiments verify the reliability of this method. The results demonstrate that this rapid and convenient method could be used for the effective enrichment and sensitive detection of poisons in several oily matrix and has the grate potential application in emergency response and public safety.


Assuntos
Venenos , Análise Espectral Raman , Diquat , Etanol , Paraquat , Venenos/análise , Reprodutibilidade dos Testes
8.
Mar Drugs ; 19(2)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540777

RESUMO

A potent and heat-stable tetrodotoxin (TTX) has been found to accumulate in various marine bivalve species, including Pacific oysters (Crassostrea gigas), raising a food safety concern. While several studies on geographical occurrence of TTX have been conducted, there is a lack of knowledge about the distribution of the toxin within and between bivalves. We, therefore, measured TTX in the whole flesh, mantle, gills, labial palps, digestive gland, adductor muscle and intravalvular fluid of C. gigas using liquid chromatography-tandem mass spectrometry. Weekly monitoring during summer months revealed the highest TTX concentrations in the digestive gland (up to 242 µg/kg), significantly higher than in other oyster tissues. Intra-population variability of TTX, measured in the whole flesh of each of twenty animals, reached 46% and 32% in the two separate batches, respectively. In addition, an inter-population study was conducted to compare TTX levels at four locations within the oyster production area. TTX concentrations in the whole flesh varied significantly between some of these locations, which was unexplained by the differences in weight of flesh. This is the first study examining TTX distribution in C. gigas and the first confirmation of the preferential accumulation of TTX in oyster digestive gland.


Assuntos
Crassostrea/química , Venenos/análise , Tetrodotoxina/análise , Poluentes Químicos da Água/análise , Animais , Trato Gastrointestinal/química , Brânquias/química , Espectrometria de Massas em Tandem/métodos , Distribuição Tecidual/fisiologia
9.
Bioelectrochemistry ; 139: 107743, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33524655

RESUMO

A "honeycomb" electrochemical biosensor based on 3D printing was developed to noninvasively monitor the viability of 3D cells and evaluate the individual or combined toxicity of deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), and 15-acetyldeoxynivalenol (15-ADON). Carbon nanofiber (CN)/gelatin methacryloyl (GelMA) conductive composite hydrogel with strong processability was printed on 8-channel screen-printed carbon electrodes (SPCEs) to maintain cell viability and form tight cell-to-cell contacts. A "3D honeycomb" printing infill pattern was selected in the construction of the biosensors to improve conductivity. Based on 3D printing technology, the electrochemical biosensor can prevent manual error and provide for high-throughput detection. Electrochemical impedance spectroscopy (EIS) was used to evaluate mycotoxin toxicity. The EIS response decreased with the concentration of DON, 3-ADON and 15-ADON in the range of 0.1-10, 0.05-100, and 0.1-10 µg/mL, respectively, with a limit of detection of 0.07, 0.10 and 0.06 µg/mL, respectively. Mycotoxin interactions were analyzed using the isobologram-combination index (CI) method. The electrochemical cytotoxicity evaluation result was confirmed by biological assays. Therefore, a novel method for evaluating the combined toxicity of mycotoxins is proposed, which exhibits potential for application to food safety and evaluation.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Venenos/análise , Tricotecenos/análise , Células A549 , Carbono/química , Sobrevivência Celular , Eletrodos , Gelatina/química , Humanos , Hidrogéis/química , Nanofibras/química , Impressão Tridimensional , Espécies Reativas de Oxigênio/análise
10.
Toxins (Basel) ; 14(1)2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-35050983

RESUMO

The presence of mycotoxins in cereals and cereal products remains a significant issue. The use of natural ingredients such as pumpkin and whey, which contain bioactive compounds, could be a strategy to reduce the use of conventional chemical preservatives. The aim of the present work was to study the bioaccessibility of aflatoxin B1 (AFB1) and ochratoxin (OTA) in bread, as well as to evaluate the effect of milk whey (with and without lactic acid bacteria fermentation) and pumpkin on reducing mycotoxins bioaccessibility. Different bread typologies were prepared and subjected to an in vitro digestion model. Gastric and intestinal extracts were analyzed by HPLC-MS/qTOF and mycotoxins bioaccessibility was calculated. All the tested ingredients but one significantly reduced mycotoxin intestinal bioaccessibility. Pumpkin powder demonstrated to be the most effective ingredient showing significant reductions of AFB1 and OTA bioaccessibility up to 74% and 34%, respectively. Whey, fermented whey, and the combination of pumpkin-fermented whey showed intestinal bioaccessibility reductions between 57-68% for AFB1, and between 11-20% for OTA. These results pointed to pumpkin and milk whey as potential bioactive ingredients that may have promising applications in the bakery industry.


Assuntos
Aflatoxina B1/análise , Pão/microbiologia , Cucurbita/química , Fungicidas Industriais/química , Leite/química , Ocratoxinas/análise , Venenos/análise , Animais , Microbiologia de Alimentos , Soro do Leite/química
11.
Toxins (Basel) ; 14(1)2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-35050984

RESUMO

Mycotoxicoses in animals are caused by exposure to mycotoxin-contaminated feeds. Disease risk is managed using dietary adsorbing agents which reduce oral bioavailability. The objective of this work was to evaluate the efficacy of three selected yeast products as mycotoxin binders using in vitro and in vivo models. Their capacity to adsorb deoxynivalenol (DON), zearalenone (ZEA), and ochratoxin A (OTA) was evaluated using an in vitro model designed to simulate the pH conditions during gastric passage in a monogastric animal. Results showed that only one product, an enzymatic yeast hydrolysate (YHY) of a novel strain Saccharomyces cerevisiae, adsorbed about 45% of DON in solution. Next, we determined the effect of YHY on oral absorption of a DON, ZEA, and OTA mixture using a toxicokinetic model in swine. Toxicokinetic modeling of the plasma concentration-time profiles of DON, OTA, and zearalenone-glucuronide (ZEA-GlcA) showed that YHY tended to reduce the maximal plasma concentration of OTA by 17%. YHY did not reduce oral bioavailability of OTA, DON, and ZEA-GlcA. Within the context of this experiment, and despite some positive indications from both the in vitro and in vivo models employed, we conclude that the YHY prototype was not an effective agent for multiple mycotoxin adsorption.


Assuntos
Fungicidas Industriais/farmacologia , Micotoxinas/análise , Venenos/análise , Saccharomyces cerevisiae/química , Fermento Seco/farmacologia , Adsorção , Ocratoxinas/análise , Tricotecenos/análise , Zearalenona/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-32692287

RESUMO

This paper demonstrates the development of an analytical method based on CE coupled to ESI-MS for the identification and quantification of fumonisin mycotoxins. Separation and detection parameters (pH of background electrolyte (BGE), organic modifier content, sheath liquid (SL) composition, MS mode and nebuliser pressure) were optimised. Ammonium formate/ammonia (pH = 9.5) with 10% ACN modifier was found the most suitable BGE. Positive mode MS was used for detection by scanning the m/z range of 400-1200. Separation was highly affected by the nebuliser pressure, a 25% improvement in peak resolution was achieved by applying the optimised parameters. The 'dilute and shoot' approach was applied to overcome disturbing effects caused by the matrix of fungi supernatant samples. The available sample volume affected the reproducibility of the measurements greatly: the scattering of peak intensities were between 4 and 11 RSD% instead of 27-195 RSD% for fumonisin B1 and fumonisin B2 when the available volume was ~200 µL instead of ~20 µL. Quantitative determinations were carried out in Fusarium verticillioides and Fusarium proliferatum culture supernatant (raw) and mycelium (cleaned up) samples. The optimised method enabled the detection of 11 fumonisins in Fusarium proliferatum inoculated rice samples; 2 of them were quantified based on external calibration and 4 other compounds with fumonisin-like formulas were detected.


Assuntos
Fumonisinas/análise , Fusarium/química , Micélio/química , Venenos/análise , Eletroforese Capilar , Espectrometria de Massas , Estrutura Molecular
13.
Int J Food Microbiol ; 330: 108667, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32531666

RESUMO

Fusarium fujikuroi species complex (FFSC) species are commonly encountered infecting rice, but knowledge of the diversity and toxigenic potential of the species is lacking in Brazil, the largest rice-producing country outside Asia. One hundred FFSC isolates obtained from national rice were identified using morphology and phylogeny of TEF, CAL and TUB genes. Eight previously known and one novel Fusarium species were identified. Three species accounted for around 60% of the strains: F. fujikuroi (n = 23), F. proliferatum (n = 22) and F. verticillioides (n = 16). The less frequent species were F. volatile (n = 8), F. anthophilum (n = 6), F. pseudocircinatum (n = 4), F. sterilihyphosum (n = 2) and F. begoniae (n = 1). The novel Fusarium species was represented by 18 isolates. All species produced at least one of the analyzed mycotoxins [beauvericin (BEA), fumonisins (FBs), moniliformin (MON) and enniatins (ENNs)]. BEA was produced by all species but F. verticillioides. The FBs (mainly FB1) were produced mostly by F. fujikuroi, F. proliferatum and F. verticillioides. F. begoniae and F. verticillioides did not produce ENNs and F. sterilihyphosum and F. begoniae did not produce MON, while the other species produced MON and ENNs. Our results add new knowledge of the diversity, geographical distribution and host range of FFSC species.


Assuntos
Fusarium/química , Fusarium/classificação , Oryza/microbiologia , Biodiversidade , Brasil , Fusarium/genética , Fusarium/isolamento & purificação , Especificidade de Hospedeiro , Micotoxinas/análise , Filogenia , Venenos/análise
14.
Vet Med Sci ; 6(3): 617-622, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32233079

RESUMO

The greater cane rat, as it is commonly known, is often called grasscutter (in Ghana, Nigeria and other regions of West Africa). Even though is highly patronized as a delicacy by a majority of Ghanaians (akrantie-Twi language) mostly in the rural areas, the persistent reports on people being poisoned as a result of eating food prepared with grasscutter which has been captured/killed by the use of poison are deterring people from consuming the grasscutter meat despite its high protein content. The objective of this study was, therefore, to investigate the actual ingredients that are used in the formulation of poison to capture grasscutter for human consumption. Questionnaires were administered to participants (farmers) who are involved in grasscutter hunting to solicit the ingredient they formulate to poison the grasscutter in their hunting. To prove the activeness of these ingredients, the main ingredient used in formulating the poison to capture the grasscutters were tested on two male grasscutters and these were yellow oleander root (Cascabela thevetia; syn: Thevetia peruviana) powder and carbofuran. The findings of the experimental trial revealed that the grasscutter that was fed with yellow oleander root powder did not die but showed some signs of intoxication and staggered each time it tried to move. However, the grasscutter fed with carbofuran died within 10 hr of being poisoned. Majority of the participants attested to the fact that the use of poison increases their chance of capturing the grasscutter, especially in the dry season since the poison is not washed away by the rainwater. However, consuming grasscutter poisoned with either yellow oleander root power or carbofuran could be detrimental to human health.


Assuntos
Contaminação de Alimentos/análise , Carne/análise , Venenos/análise , Roedores , Animais , Gana , Venenos/efeitos adversos
15.
J Chromatogr A ; 1614: 460736, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31831146

RESUMO

This article describes a new simultaneous method for the analysis of sulfur-type poisons, hydrocarbons and permanent gases affecting the productivity of the Ziegler Natta catalyst during the synthesis of polypropylene on an industrial scale in a fluidized-bed reactor. The identification was achieved employing a configuration of the seven-valve chromatographic system, with events at different times, allowing distribution of the sample through multiple columns, and finally reaching the helium ionization detectors of pulsed discharge, flame ionization and mass spectrometry. The results obtained show a good precision of the method used because the variability was less than 1.02% in area and 0.49% in retention time for short term precisión and longer term precision . The quantification of these species was successful after performing the calibration curve with the dynamic mixer showing an r2 higher than 0.9945 and excellent linearity. The lowest LOD value was 0.01 mg kg-1 for carbonyl sulphide, hydrogen sulfide, ethylmercaptan and propylmercaptan and the lowest LOQ was 0.03 mg kg-1 for hydrogen sulfide. The highest LOD and LOQ values were for oxygen and carbon dioxide with 0.40 and 0.93 mg kg-1 respectively. With this configuration, the correlation of data between the three detectors was simplified, having almost identical retention times for the analytes studied. The poisons detected and quantified in the samples were: hydrogen sulfide (0.1-0.5 mg kg-1), carbonyl sulphide (0.012-0.06 mg kg-1), carbon disulphide (0.04-0.22 mg kg-1), methylmercaptan (0.12-12.51 mg kg-1), ethylmercaptan (0.9-5.5 mg kg-1), carbon dioxide (0.10-3.0 mg kg-1), oxygen (0.55-6.1 mg kg-1), acetylene (0.15-3.5 mg kg-1) and methylacetylene (0.04-0.2 mg kg-1). The productivity losses were between 5 and 22%.


Assuntos
Cromatografia Gasosa , Ionização de Chama , Hélio/química , Espectrometria de Massas , Venenos/análise , Polipropilenos/síntese química , Calibragem , Catálise , Hidrocarbonetos/análise , Sulfeto de Hidrogênio/análise
16.
J Chem Ecol ; 45(11-12): 914-925, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31802386

RESUMO

Frogs in the genus Phyllobates are known for the presence of batrachotoxin, a highly toxic alkaloid, in their skin. Nevertheless, Phyllobates frogs from Costa Rica and Panama (P. lugubris and P. vittatus) are considered non-toxic, as they have been reported to harbor low concentrations of this alkaloid. However, the potential toxicity of Central American Phyllobates has not been assessed experimentally. Our goal was to determine the toxicity of the whole skin of P. vittatus, an endemic species from the Southeastern Pacific region of Costa Rica. We performed median lethal dose (LD50) tests in mice to determine general toxicity, and an irritant assay based on the behavioral responses of mice to subcutaneous injection, to determine differences in irritability, as a measure of toxicity, among three study localities. Using UPLC-ESI-QTOF, we obtained chemical profiles of the methanolic extract of frog skins. Due to the absence of mortality at the studied doses, we were unable to estimate LD50. However, we recorded a list of toxicity symptoms in mice that are consistent with cardiotoxic effects, and found that mice presented more symptoms at higher concentrations of skin extracts during the first hour of the LD50 assays, recovering completely at all doses by the end of the assay. On the other hand, we did not detect differences in irritability among studied localities. Additionally, we putatively identified three toxic alkaloids (Batrachotoxinin A, DHQ 251A and Lehm 275A). This study provides the first experimental data on the toxicity and associated symptoms in mice, as well as the chemical profile of the skin of P. vittatus. We suggest that the skin alkaloids of P. vitattus may confer a chemical defense towards predators.


Assuntos
Alcaloides/análise , Alcaloides/toxicidade , Anuros/fisiologia , Misturas Complexas/análise , Misturas Complexas/toxicidade , Pele/química , Animais , Cromatografia Líquida de Alta Pressão/métodos , Simulação por Computador , Costa Rica , Bases de Dados de Compostos Químicos , Feminino , Dose Letal Mediana , Camundongos Endogâmicos ICR , Venenos/análise , Venenos/toxicidade , Espectrometria de Massas em Tandem/métodos
17.
Artigo em Inglês | MEDLINE | ID: mdl-31569703

RESUMO

Among the array of structurally and toxicologically diverse mycotoxins, aflatoxins have attracted the most interest of scientific research due to their high toxicity and incidence in foods and feeds. Despite the undeniable progress made in various aspects related to aflatoxins, the ultimate goal consisting of reducing the associated public health risks worldwide is far from being reached due to multiplicity of social, political, economic, geographic, climatic, and development factors. However, a reasonable degree of health protection is attained in industrialized countries owing to their scientific, administrative, and financial capacities allowing them to use high-tech agricultural management systems. Less fortunate situations exist in equatorial and sub-equatorial developing countries mainly practicing traditional agriculture managed by smallholders for subsistence, and where the climate is suitable for mould growth and aflatoxin production. This situation worsens due to climatic change producing conditions increasingly suitable for aflatoxigenic mould growth and toxin production. Accordingly, it is difficult to harmonize the regulatory standards of aflatoxins worldwide, which prevents agri-foods of developing countries from accessing the markets of industrialized countries. To tackle the multi-faceted aflatoxin problem, actions should be taken collectively by the international community involving scientific research, technological and social development, environment protection, awareness promotion, etc. International cooperation should foster technology transfer and exchange of pertinent technical information. This review presents the main historical discoveries leading to our present knowledge on aflatoxins and the challenges that should be addressed presently and in the future at various levels to ensure higher health protection for everybody. In short, it aims to elucidate where we come from and where we should go in terms of aflatoxin research/development.


Assuntos
Aflatoxinas/toxicidade , Pesquisa Biomédica/história , Microbiologia de Alimentos/história , Micotoxicose/história , Venenos/toxicidade , Aflatoxinas/análise , Aflatoxinas/química , Agricultura/história , Agricultura/métodos , Pesquisa Biomédica/métodos , Mudança Climática , Países em Desenvolvimento , Microbiologia de Alimentos/métodos , Saúde Global , Política de Saúde , História do Século XVII , História do Século XIX , História do Século XX , História Antiga , Humanos , Micotoxicose/diagnóstico , Micotoxicose/etiologia , Micotoxicose/terapia , Venenos/análise , Venenos/química , Estudos Prospectivos , Saúde Pública/história , Estudos Retrospectivos
18.
Food Chem Toxicol ; 128: 171-179, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30965105

RESUMO

In order to understand the changes in toxic metabolite profiles in uncooked and cooked foods, samples of flour/grain (n = 40) and their corresponding plate-ready food (n = 39) were collected from 40 households in two states of northern Nigeria. The food samples were analyzed for multiple fungal metabolites by LC-MS/MS and daily intakes of mycotoxins in the diets were estimated and compared to established margin of exposure (MOE) and tolerable daily intake (TDI) values. Both food groups contained 65 fungal and plant metabolites, inclusive of 23 mycotoxins. The mean concentrations of aflatoxin B1, beauvericin, fumonisin B1 (FB1), FB2, FB3, hydrolysed FB1, moniliformin and nivalenol were significantly (p < 0.05) higher in flour than in the plate-ready food samples. The levels of several mycotoxins were higher in the flour samples than in plate-ready meals by 129-383%. The dilution effect from proportionate mixing of flour samples with water led to 48-100% reduction in detectable mycotoxins in flour to plate-ready meals. Aflatoxins and fumonisins co-occurred in 36% of the plate-ready foods. Exposures of households to aflatoxins and fumonisins based on 95% CI concentration of mycotoxins in the meals were high, suggesting potential health risks based on calculated low MOE and exceedence of stipulated TDI value, respectively.


Assuntos
Culinária , Características da Família , Contaminação de Alimentos/análise , Micotoxinas/análise , Venenos/análise , Saúde da População Rural , Adolescente , Adulto , Aflatoxinas/análise , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Cromatografia Líquida , Exposição Dietética , Feminino , Fumonisinas/análise , Humanos , Lactente , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Nigéria , Espectrometria de Massas em Tandem , Adulto Jovem
19.
Mycotoxin Res ; 35(2): 207-216, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30859459

RESUMO

The aim of the present study was to evaluate the occurrence of 23 mycotoxins in beer purchased in Mexico and to assess two exposure scenarios in the Mexican population through beer consumption. Multi-mycotoxin analysis of a total of 61 different beers (132 samples) was carried out using UHPLC-MS/MS equipment. Probability density functions were used to describe mycotoxins contamination. The daily intake of mycotoxins was estimated using a semi-probabilistic approach, applying the Monte Carlo method. Deoxynivalenol (DON) and its metabolites (deoxynivalenol-3-glucoside (DON3G) and 3-acetyl-deoxynivalenol (3ADON)) were the mycotoxins found in higher proportions in contaminated samples. None of the other mycotoxins overpassed the limit of quantification (LOQ) of the method. The combined intake of DON and its analogues ranged from 5.24 to 86.59 ng kg-1 bw day-1, which represent from 1.20 to 19.83% of the DON TDI. The results suggest that depending on the individual consumption of beer and depending on the type of beer, the intake of DON via beer could represent a significant percentage of the tolerable daily intake (TDI).


Assuntos
Cerveja/análise , Contaminação de Alimentos/análise , Micotoxinas/análise , Venenos/análise , Tricotecenos/análise , Exposição Ambiental , México
20.
Mycotoxin Res ; 35(2): 169-176, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30706435

RESUMO

The aim of this study was to compare the fate of fumonisins in transgenic and non-transgenic corn during industrial dry milling. For this purpose, whole corn samples and their fractions (germ, pericarp, endosperm, corn meal, and grits) were collected from one of the major Brazilian milling plants, totaling 480 samples. There was no significant difference (p > 0.05) between mean fumonisin (FB1 + FB2) levels in transgenic (1130 µg/kg) and non-transgenic (920 µg/kg) whole corn. However, in non-transgenic germ, endosperm and corn meal fraction fumonisin levels were higher (2940 µg/kg, 250 µg/kg and 190 µg/kg, respectively) than in transgenic fractions (2180 µg/kg, 130 µg/kg and 85.0 µg/kg, respectively). Furthermore, the highest percentages of fumonisins were distributed in the germ, corresponding to about 87 and 76% of the total fumonisins present in the whole corn from non-transgenic and transgenic hybrids, respectively. Concerning the endosperm from non-transgenic and transgenic corn, approximately, 23% and 13% of the total fumonisins were retained after the dry milling. Further processing in corn meal (300 to 420 µm particle size) and grits (590 to 1190 µm) decreased the percentages of remaining fumonisins to 4% and 2% (transgenic) and 10% and 3% (non-transgenic corn), respectively. These results suggested that fumonisin concentration was higher in outer and inner non-transgenic fractions when compared to transgenic ones and that the fate of fumonisins during the industrial dry milling could be affected by the transgenic status. However, it was not possible to conclude that the difference was exclusively due to this variable.


Assuntos
Contaminação de Alimentos/análise , Fumonisinas/análise , Plantas Geneticamente Modificadas/química , Venenos/análise , Zea mays/química , Brasil , Indústria Alimentícia
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