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1.
China Journal of Chinese Materia Medica ; (24): 385-391, 2022.
Artigo em Chinês | WPRIM | ID: wpr-927980

RESUMO

This study aimed to analyze aflatoxins content and fungal community distribution in the harvesting and processing of Platycladi Semen, and explore the key link that affects aflatoxins contamination. The related Platycladi Semen samples of different maturity periods(cone non-rupture period, early rupture, and complete rupture period) and different processing periods(before drying, during 2-d drying, during 7-d drying, before and after seed scale removal, before and after peeling, 1 d after color sorting, and 7 d after color sorting) were collected for identifying the fungal community composition on sample surface by ITS amplicon sequencing. Then the content of aflatoxins B_1, B_2, G_1 and G_2 was determined by HPLC-MS/MS. The results showed that during the harvesting of Platycladi Semen from cone non-rupture to complete rupture, aflatoxins were only detected in the seed scale and seed coat, with aflatoxin G_2 in the seed scale and aflatoxin B_1 in the seed coat. During the drying, with the prolongation of drying time, aflatoxins B_1 and G_2 were detected simultaneously in the seed scale, aflatoxin B_1 in the seed coat, and low-content aflatoxin B_1 in the seed kernel. During subsequent processing, the aflatoxin content in seed kernel during subsequent processing was slighted increased. As demonstrated by fungal detection, Aspergillus flavus was not present during the harvesting of Platycladi Semen, but present during the drying and processing. Its content in the seed coat during the drying process was relatively higher. In short, Platycladi Semen should be harvested as soon as possible after it becomes fully mature. Drying process is the key link of preventing aflatoxin contamination. It is advised to build a sunlight room or adopt similar settings, standardize the operations in other processes, and keep the surrounding environment clean to minimize aflatoxin contamination.


Assuntos
Aflatoxinas/análise , Aspergillus flavus , Contaminação de Alimentos/prevenção & controle , Micobioma , Sêmen/química , Espectrometria de Massas em Tandem
2.
China Journal of Chinese Materia Medica ; (24): 628-634, 2022.
Artigo em Chinês | WPRIM | ID: wpr-927944

RESUMO

This study aimed to establish a method for synchronous detection of 14 mycotoxins in Pseudostellariae Radix and investigate its contamination with mycotoxins, so as to provide technical guidance for monitoring the quality of Chinese medicinal materials and medication safety. The sample was extracted with 80% acetonitrile in an oscillator for 1 h, purified using the modified QuEChERS purifying agent(0.1 g PSA + 0.3 g C_(18) + 0.3 g MgSO_4), and separated on a Waters HSS T3 chromatographic column(2.1 mm×100 mm, 1.8 μm). The gradient elution was carried out with 0.1% formic acid in water and acetonitrile, followed by the scanning in the multi-reaction monitoring(MRM) mode and the analysis of mycotoxin contamination in 26 Pseudostellariae Radix samples. The recovery rates of the established method were within the range of 82.17%-113.6%, with the RSD values less than 7% and the limits of quantification(LOQ) being 0.019-0.976 μg·kg~(-1). The detection rate of 14 mycotoxins in 26 batches of medicinal materials was 53.85%. The detection rate of sterigmatocystin(ST) was the highest, followed by those of zearalenone(ZEN), aflatoxin G_2(AFG_2), fumonisin B_1(FB_1), HT-2 toxin, and nivalenol(NIV). Their respective detection rates were 38.46%, 26.92%, 23.08%, 11.54%, 11.54%, and 7.69%, with the pollution ranges being 1.48-69.65, 0.11-31.05, 0.11-0.66, 0.28-0.83, 20.86-42.56, and 0.46-1.84 μg·kg~(-1), respectively. The established method for the detection of 14 mycotoxins is accurate, fast and reliable. The research results have very important practical significance for guiding the monitoring and prevention and control of exogenous fungal contamination of Chinese medicinal materials.


Assuntos
Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Contaminação de Alimentos/análise , Micotoxinas/análise , Raízes de Plantas/química , Espectrometria de Massas em Tandem/métodos
3.
Rev. Inst. Adolfo Lutz ; 79: e1783, 31 mar. 2020. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1489614

RESUMO

Micotoxinas são substâncias tóxicas produzidas por fungos e encontradas nos alimentos. As micotoxinas mais tóxicas são as aflatoxinas, produzidas, principalmente por Aspergillus flavus. Estudos realizados no país demonstraram alta incidência dessas micotoxinas em produtos de amendoim, que representa risco à saúde da população. O objetivo do estudo foi avaliar a incidência de aflatoxinas B1, B2, G1 e G2 em amostras de amendoins comercializados na região Nordeste do Estado de São Paulo nos períodos de 1994-2001 e 2016-2017. O método utilizado para analisar as amostras no primeiro período foi extração líquido-líquido e cromatografia em camada delgada e no segundo foi utilizando colunas de imunoafinidade, cromatografia líquida com derivatização pós-coluna e detector por fluorescência. No levantamento de 1994-2001 das 82 amostras, 39% tiveram contaminação de aflatoxinas variando de 11 a 1556 μg/kg com 37% das amostras contendo níveis maiores que 20 μg/kg, enquanto na pesquisa de 2016-17, das 56 amostras, 38% apresentaram contaminação destas toxinas variando de 0,09 a 60,40 μg/kg com 13% das amostras contendo níveis maiores que 20 μg/kg. Os resultados dos dois períodos estudados indicam que houve uma diminuição na incidência e nível das aflatoxinas estudadas, embora esta contaminação em amendoim permaneça um problema de saúde pública.


Mycotoxins are toxic compounds produced by fungi found in food. The most toxic mycotoxins are the aflatoxins produced mainly by Aspergillus flavus. Studies carried out in Brazil showed a high incidence of these mycotoxins in peanut products, a fact that represents public health problems. The aim of the study was to evaluate aflatoxins B1, B2, G1, and G2 in samples of peanuts sold in cities of the Northeast of the State of São Paulo in the period from 1994 to 2001 and from 2016 to 2017. The samples of the first period were analyzed using liquid-liquid extraction and thin-layer chromatography and the second using immunoaffinity columns, post-column derivative liquid chromatography and fluorescence detector. In the 1994-2001 survey, among 82 samples, 39% presented aflatoxins contamination ranging from 11 to 1556 μg/kg with 37% with levels greater than 20 μg/kg whereas, in the 2016-17 survey, 38% of the 56 samples presented contamination of aflatoxins ranging from 0.09 to 60.40 μg/kg and 7 samples 13% containing aflatoxins levels higher than 20 μg/kg. The results indicated there was a decrease in the incidence and level of aflatoxins, but the contamination of aflatoxins in peanuts remains a public health problem.


Assuntos
Aflatoxinas/análise , Arachis/microbiologia , Aspergillus flavus , Cromatografia em Camada Fina , Estudos de Coortes , Incidência , Micotoxinas
4.
Hig. aliment ; 32(286/287): 61-64, dez. 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1481871

RESUMO

Aflatoxicose é uma intoxicação resultante da ingestão de aflatoxinas presentes nos alimentos. O quadro clínico está diretamente relacionado ao grau de contaminação do produto, tempo e quantidade ingerida pelo individuo assim como seu estado nutricional. O presente estudo teve como objetivo analisar a presença de aflatoxina em amostras selecionadas de pastas de amendoim comercializadas em Belo Horizonte, MG e correlacionar com a legislação vigente no Brasil e em outros países. Para tal, foram coletadas uma amostra de cada marca diferente de pasta de amendoim integral, sem adição de outros ingredientes, comercializadas no Mercado Central, em Belo Horizonte-MG, em dezembro de 2016. Como critério de escolha foram selecionadas todas as marcas comercializadas no referido estabelecimento, com a descrição de pasta de amendoim integral sem adição de açúcar e outros ingredientes. Os resultados mostraram que em todas as amostras analisadas a quantidade de aflatoxina encontrada foi menor que 2,0 µg/kg de amostra, dentro do recomendado na legislação brasileira e internacional.


Aflatoxicosis is an intoxication caused by the ingestion of aflatoxins present in food. The symptoms are directly related to the degree of contamination of the product, time and amount of ingest by the individual as well as their nutritional status. The present study aimed to determine the presence of aflatoxin in peanut pastes commercialized in Belo Horizonte, MG and correlate with current legislation in Brazil and other countries. For this purpose, six samples of whole peanut paste, without addition of other ingredients, commercialized at the Central Market in Belo Horizonte, MG, in December 2016. As a selection criterion, all the brands marketed in the establishment were selected. Description of whole peanut paste without added sugar and other ingredients. The results showed that in all analyzed samples the amount of aflatoxin found was lower than 2.0 µg / kg of sample, within the recommended in international and Brazilian legislation.


Assuntos
Aflatoxinas/análise , Aflatoxinas/normas , Alimentos de Amendoim , Limites Permissíveis de Riscos Ocupacionais , Micotoxinas
5.
Arch. latinoam. nutr ; 64(1): 42-49, mar. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-752690

RESUMO

Se realizó un estudio de las condiciones del procesamiento del café de exportación en 15 beneficios, ubicados en Chiriquí, región occidental de Panamá. Además se analizaron 21 muestras de café procesado (grano verde), provenientes de los beneficios. Las muestras fueron analizadas microbiológicamente y se cuantificaron las Aflatoxinas totales (B1, B2, G1 y G2) y Ocratoxina A (OTA), mediante el método de inmunoafinidad ELISA. Se determinó un límite de detección de 0,017 ng/mL, para la Ocratoxina A, lo que equivale a una concentración de 0,829 μg/kg en la muestra, y un límite de detección de 0,027 ng/mL, para las Aflatoxinas totales, lo que equivale a una concentración de 1,350 μg/kg de Aflatoxinas totales. En la muestra, se encontró que cuatro de las 21 (19%) resultaron positivas a la presencia de Ocratoxina A y tres, a la presencia de Aflatoxinas totales (14%). Las muestras presentaron niveles de Ocratoxina A en el rango de 4,90-37,73 μg/kg; sólo tres de ellas superaron el límite máximo permitido por la Unión Europea, para la concentración de Ocratoxina, que es de 5,0 μg/kg. Las Aflatoxinas totales se encontraron en el rango de 1,51- 1,93 μg/kg, por debajo de los 10 μg/kg, que es el límite máximo permitido en el café por la Unión Europea. Los resultados nos indican que el procesamiento de café producido en Panamá cumple satisfactoriamente con los estándares internacionales de manejo poscosecha, lo que conduce a una baja incidencia de hongos productores de micotoxinas y niveles muy bajos de micotoxinas.


Levels of Ochratoxin A and total Aflatoxins in Panamanian exportation coffee by an ELISA Method. A study about processing conditions of exportation coffee in 15 benefits located in Chiriquí, western region of Panama, was conducted. In addition, 21 samples of processed coffee (green beans), from the benefits, were analyzed. The samples were microbiologically tested in order to quantify total aflatoxins (B1, B2, G1 and G2) and Ochratoxin A (OTA), using the immunoaffinity ELISA method. A detection limit of 0.017 ng/mL, was determined for Ochratoxin A, which is equivalent to a concentration of 0.829 μg/kg, and a detection limit of 0.027 ng/mL, for total aflatoxins, which is equivalent to a concentration of 1.350 μg/kg. It was found that four (19%) out of the 21 samples were positive to the presence of Ochratoxin A and three (14%) to the presence of total aflatoxins. Samples showed levels of Ochratoxin A in the range 4.90 - 37.73 μg/kg; only three of them exceeded the maximum limit allowed by the European Union, for the concentration of Ochratoxin, which is of 5.0 μg/kg. Total aflatoxins were found in the range 1.51 - 1.93 μg/kg, below 10μg/kg which is the maximum limit allowed for coffee by the European Union. The results indicate that the processing of coffee produced in Panama successfully meets international standards for postharvest handling, which leads to a low incidence of mycotoxins and very low levels of mycotoxin- producing fungi.


Assuntos
Aflatoxinas/análise , Café/química , Ocratoxinas/análise , Cromatografia Líquida de Alta Pressão , Comércio , Ensaio de Imunoadsorção Enzimática , Contaminação de Alimentos/análise , Panamá , Padrões de Referência
6.
Braz. j. microbiol ; 45(1): 35-42, 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-709476

RESUMO

Variance and performance of two sampling plans for aflatoxins quantification in maize were evaluated. Eight lots of maize were sampled using two plans: manual, using sampling spear for kernels; and automatic, using a continuous flow to collect milled maize. Total variance and sampling, preparation, and analysis variance were determined and compared between plans through multifactor analysis of variance. Four theoretical distribution models were used to compare aflatoxins quantification distributions in eight maize lots. The acceptance and rejection probabilities for a lot under certain aflatoxin concentration were determined using variance and the information on the selected distribution model to build the operational characteristic curves (OC). Sampling and total variance were lower at the automatic plan. The OC curve from the automatic plan reduced both consumer and producer risks in comparison to the manual plan. The automatic plan is more efficient than the manual one because it expresses more accurately the real aflatoxin contamination in maize.


Assuntos
Aflatoxinas/análise , Análise de Alimentos/métodos , Zea mays/química , Automação Laboratorial/métodos , Reprodutibilidade dos Testes
7.
PJMR-Pakistan Journal of Medical Research. 2014; 53 (3): 67-70
em Inglês | IMEMR | ID: emr-148860

RESUMO

Aflatoxins are mould metabolites of Aspargillus flavus and parasiticus that contaminate foodstuffs stored in warm moist places. These toxins are hepatotoxic and produce hepatocellular carcinoma in animals and man. To determine the presence of aflatoxins and microorganisms in ready to consume products of peanuts and sunflower seeds of an edible oil processing factory. Five hundred grams each of peanut kernels, peanut pellets, sunflower seed pellets, peanut oil and sunflower seed oil produced by a local oil extracting factory were supplied for extraction and estimation of aflatoxins and microorganisms like Salmonella, Escherichia coli [E.coli], Bacillus and Moulds. Aflatoxins B[1], B[2], G[1] and G[2] were extracted in chloroform and concentration was measured using silica gel columns. The quantitative estimation of these aflatoxins B[1], B[2], G[1] and G[2] was done by fluorescence evaluation on Thin Layer Chromatograms. All test samples contained four types of aflatoxins. The highest aflatoxin values were seen in the pellets and lowest in refined oils. All samples contained higher content of aflatoxins B[1] and B[2] than G[1] and G[2]. Refined peanut oil contained much lower aflatoxin than the sunflower seed oil. This study has also identified the presence of several types of microorganisms such as Salmonella, E. coli, Bacillus and Moulds in ready to eat peanut and sunflower seed products. Detection of high levels of aflatoxins and microorganisms in ready to eat food stuff should be a concern for food regulatory agencies since these products are consumed daily by the common man and their cumulative effect on the body might be adding to liver cancer in the population. Food regulatory agencies should regularly carry out thorough surveillance on food stuff


Assuntos
Aflatoxinas/análise , Arachis/microbiologia , Helianthus/microbiologia , Sementes/microbiologia , Substâncias Perigosas , Contagem de Colônia Microbiana
8.
Braz. j. microbiol ; 43(4): 1444-1451, Oct.-Dec. 2012. tab
Artigo em Inglês | LILACS | ID: lil-665831

RESUMO

The mycoflora of the environment: wheat conditioning, milling and screening, and filling zone, as well as, raw material -wheat-, intermediate product -grits- and end product -flour- on day 1, and after cleaning improvements -days 45 and 90- were studied in an Argentine wheat mill. Samples were incubated at 28°C for 5-7 days on Malt Extract Agar with chloramphenicol (100 mg L-1) and the results were expressed in colony forming units per cubic meter of air (CFU m-3) or per gram of sample (CFU g-1), respectively. Fungal genera and species were isolated and identified and the potential toxicogenic capacity of the Aspergillus flavus and Fusarium graminearum isolated was studied. Time-Place and Time-Product multifactorial ANOVA were carried out. After cleaning improvements, CFU m-3 of air decreased as a function of time. Cladosporium and Alternaria were abundant in every zone, Aspergillus predominated in the wheat conditioning zone and Penicillium and Eurotium decreased with time. Wheat was more contaminated than grits and flour; Aspergillus, Eurotium and Mucoraceae family were the most abundant. Deoxynivalenol was above the levels allowed in wheat, being acceptable in grits and flour. Aflatoxin and Zearalenone showed acceptable levels. When studied in vitro, 53% of Aspergillus flavus and 100% of Fusarium graminearum isolates, produced Total Aflatoxins, and Deoxynivalenol and Zearalenone, respectively.


Assuntos
Aflatoxinas/análise , Aflatoxinas/isolamento & purificação , Análise de Alimentos , Farinha/análise , Flora/análise , Fungos Mitospóricos/isolamento & purificação , Técnicas In Vitro , Meio Ambiente , Ensaio de Imunoadsorção Enzimática , Microbiologia de Alimentos , Amostras de Alimentos , Triticum
9.
Artigo em Inglês | LILACS | ID: lil-658497

RESUMO

The filamentous fungi Aspergillus flavus, Aspergillus parasiticus and Aspergillus nomius produce toxins, which are secondary metabolites called aflatoxins. These toxin-producing species grow rapidly on peanuts and cereals in favorable conditions of temperature and humidity. Their toxins can either cause acute effects, and even be lethal or accumulate in the organism, resulting in liver cancer in the long term. Based on the health risks of aflatoxins in food, a research was conducted on peanuts and derivatives sold in Alfenas, MG, Brazil, to evaluate the presence of Aspergillus sp. and aflatoxins. The samples were randomly collected at ?popular stores?, from November 2008 to May 2009, to assess the occurrence of aflatoxins B1, B2, G1 and G2 by thin layer chromatography (TLC). The mycological analysis revealed the presence of fungi in 50% of the samples: Penicillium sp. (53.85%), A. flavus (19.23%), A. niger (15.38%) and A. fumigatus (11.54%), and 63.64% of these showed the presence of aflatoxins : B1 (43.14%), B2 (25.49%), G1 (23.53%) and G2 (7.84%). It is concluded that the results reported here are a cause for concern, given the harmfulness of these cumulative and carcinogenic toxins.


As espécies Aspergillus flavus, Aspergillus parasiticus e Aspergillus nomius produzem micotoxinas, que são metabólitos secundários denominados de aflatoxinas. Desenvolvem-se rapidamente em amendoins e cereais produzindo esta toxina, quando em condições favoráveis de temperatura e umidade. Essas toxinas podem produzir efeitos agudos, letais ou não, ou efeito cumulativo no organismo, que a longo prazo, podem causar, principalmente, lesões carcinogênicas hepáticas. Sabendo-se dos riscos à saúde, devido à presença de aflatoxinas nos alimentos, foi realizada uma pesquisa em amendoins e derivados comercializados na cidade de Alfenas ? MG, Brasil, para avaliar a presença de aflatoxinas e de fungos do gênero Aspergillus sp. Amostras foram coletadas aleatoriamente em lojas populares no período de novembro de 2008 a maio de 2009 e avaliada a ocorrência de aflatoxinas B1, B2, G1 e G2, utilizando-se a técnica de Cromatografia de Camada Delgada (CCD). Na análise micológica foi constatada a presença de fungos em 50% das amostras, das espécies: Penicillium sp. (53,85%), A. flavus (19,23%), A. niger (15,38%), A. fumigatus (11,54%). Obteve-se como resultado para a presença de aflatoxinas 63,64 %, sendo: B1 (43,14%), B2 (25,49%), G1 (23,53%), G2 (7,84%). Concluiu-se que os números encontrados são preocupantes, tendo em vista a periculosidade desta substância


Assuntos
Aspergillus flavus , Aflatoxinas/análise , Aflatoxinas/efeitos adversos , Poluição Ambiental , Alimentos de Amendoim , Micotoxinas , Venenos
10.
Artigo em Inglês | IMSEAR | ID: sea-144664

RESUMO

Background & objectives: The present study was carried out on stored rice variety PAU 201 in Punjab that was not permitted for milling and public distribution due to the presence of damaged grains at levels exceeding the regulatory limits of 4.75 per cent. The aim of the study was to determine fungal and aflatoxin contamination in the rice samples to assess hazard from the presence of damaged grains. Presence of iron in discoloured rice grains was also assessed. Methods: Stored samples of paddy of PAU 201 rice variety were collected from six districts of Punjab, milled and analysed for presence of fungal and aflatoxin contamination. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and Prussian blue staining was used to determine fungal spores and presence of iron, respectively. Results: Aflatoxin analysis of rice samples indicated that none exceeded the Food Safety and Standards (Contaminants, Toxins and Residues) Regulations, 2011 tolerance limit of 30 μg/kg and majority of the samples had levels <15 μg/kg. The proportion of damaged grains exceeding the limit of 5 per cent was observed in 85.7 per cent of the samples. SEM and Prussian blue staining and EDX analysis of black tipped and pin point damaged rice grains did not show presence of fungal structures and presence of iron. Interpretation & conclusions: The results of the study indicated that the stored rice samples did not pose any health concern with respect to aflatoxin contamination as per the criteria laid down by the Food Safety and Standards Authority of India.


Assuntos
Aflatoxinas/análise , Ferrocianetos , Contaminação de Alimentos/análise , Microbiologia de Alimentos/normas , Microbiologia de Alimentos/estatística & dados numéricos , Índia , Microscopia Eletrônica de Varredura , Oryza/química , Oryza/microbiologia , Espectrometria por Raios X , Esporos Fúngicos/isolamento & purificação
11.
Hig. aliment ; 26(206/207): 87-92, mar.-abr. 2012.
Artigo em Português | LILACS | ID: lil-661552

RESUMO

As aflatoxinas são micotoxinas produzidas pelo metabolismo secundário de três principais espécies fúngicas, Aspergillus flavus, Aspergillus Parasiticus e Aspergillus nomius, que pode contaminar os alimentos de consumo humano e animal. A exposição por ingestão de aflatoxinas pode levar ao desenvolvimento de sérias patologias, pois são compostos imunossupressores, além de mutagênicos, carcinogênicos e teratogênicos, sendo um problema para saúde pública e para a segurança alimentar. O presente estudo teve como objetivo avaliar a presença e os níveis de contaminação por aflatoxina em paçocas de amendoim, coletadas em pontos de venda próximos ou no interior de instituições de ensino fundamental e superior, na cidade de Porto Alegre.


Assuntos
Aflatoxinas/análise , Aflatoxinas/efeitos adversos , Contaminação de Alimentos , Alimentos de Amendoim , Brasil , Comércio , Alimentos , Alimentos Industrializados
12.
Braz. j. microbiol ; 42(1): 49-56, Jan.-Mar. 2011. tab
Artigo em Inglês | LILACS | ID: lil-571374

RESUMO

Litopenaeus vannamei, which is the most common shrimp species cultivated in the northeast of Brazil, is very susceptible to microbial diseases, and this consequently affects productivity. There are reports of bacteria, viruses and protozoa in these shrimp, but not fungi. This study aims to isolate and identify fungi present in shrimp Litopenaeus vannamei, and in their nursery waters, at two breeding farms in Brazil. The pathogenic potential of the isolates was assessed through the qualitative detection of proteases and aflatoxin B production. The 146 isolated fungi comprised 46 species. Aspergillus, Penicillium and Furarium were the three most relevant genera and Aspergillus flavus was the predominant species with a total of 33 isolates. Most of the isolated species are known as potentially pathogenic to humans and other animals. Eighteen isolates of A. flavus and two of A. parasiticus were able to produce aflatoxin B and 33 out of the 46 species produced protease, indicating that these fungi may also become pathogenic to shrimp and their consumers.


Assuntos
Aflatoxinas/análise , Aflatoxinas/isolamento & purificação , Biodiversidade , Fungos Mitospóricos/enzimologia , Fungos Mitospóricos/isolamento & purificação , Penaeidae/enzimologia , Penaeidae/patogenicidade , Peptídeo Hidrolases/análise , Peptídeo Hidrolases/isolamento & purificação , Diagnóstico , Amostras de Alimentos , Métodos , Métodos , Virulência
13.
Braz. j. microbiol ; 41(1): 82-90, Jan.-Mar. 2010. ilus, graf
Artigo em Inglês | LILACS | ID: lil-531738

RESUMO

In this study, we investigated the binding ability of Saccharomayces cerevisiae to aflatoxin in pistachio nuts. The obtained results indicate that S. cerevisiae has an aflatoxin surface binding ability of 40 percent and 70 percent (with initial aflatoxin concentrations of 10 and 20 ppb) in the exponential phase. Acid treatments increase this ability to approximately 60 percent and 73 percent for the two concentrations of aflatoxin, respectively. Heat treatments also enhance surface binding to 55 percent and 75 percent, respectively. Binding appears to be a physical phenomenon that saturates within the first 2-3 hours of the process. The obtained results indicate that yeast immobilization for toxin reduction on aflatoxin-contaminated pistachios had no effect on qualitative characteristics, such as color, texture, and peroxide value. Yeast cells, viable or nonviable, are effective for aflatoxin binding, and this property could lead to a promising solution to aflatoxin contamination in high-risk foods.


Assuntos
Aflatoxinas/análise , Aflatoxinas/isolamento & purificação , Fenômenos Biológicos , Pistacia , Saccharomyces cerevisiae/isolamento & purificação , Contaminação de Alimentos , Amostras de Alimentos , Métodos , Métodos , Toxicidade
14.
Braz. j. microbiol ; 40(1): 139-144, Jan.-Mar. 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-513131

RESUMO

Quantitative losses in various biochemical constituents like capsaicin, carotenes, ascorbic acid, polyphenols,mineral matter, sugars (soluble and insoluble), protein and fat were estimated after the successful growth ofAspergillus flavus for 30 days on powdered red pepper. The fungal biomass was measured by ergosterolcontent and Aflatoxin B1 by HPLC. Amongst the various nutritional constituents evaluated for nutritionallosses and changes the highest nutritional loss was reported in total carotenoids (88.55%) followed by totalsugars (85.5%). The protein content of the infected sample increased from 18.01% to 23%. The nutritional profile of chilli powder (Capsicum annum var. sannam L.) shows highest share of total soluble sugars (32.89%) and fiber content (21.05%), followed by protein (18.01%) and fat (13.32%) making it an ideal solid - substrate for mould growth. At the end of incubation the fungal biomass was 192. 25 mg / 100 gram powder, total plate count 17.5 X 10 4 CFU/g and Aflatoxin B1 content was 30.06 μg / kg.


Foram avaliadas as perdas de vários constituintes bioquímicos como capsaicina, carotenos, acido ascórbico,polifenóis, matéria orgânica, açucares (solúveis e insolúveis), proteína e gordura em pimenta vermelha em pó após a multiplicação de Aspergillus flavus por 30 dias. A biomassa fúngica foi mensurada pelo conteúdo de ergosterol e aflatoxina por HPLC. Entre os vários constituintes avaliados, a maiorperda foi a de carotenóides totais (88,55%), seguido de açucares totais (85,5%). O conteúdo protéico da amostra infectada aumentou de 18,01% para 23%. O perfil nutricional da pimenta em pó (Capsicum annum var. sannam L.) indica alto teor de açucares totais (32,89%) e fibras (21,05%), seguido de proteína (18,01%) e gordura (13,32%), tornando-a umsubstrato ideal para crescimento de fungos. Ao final dos 30 dias, a biomassa fúngica foi 192,25 mg/100g, a contagem total em placas foi 17,5 x 104 CFU/g e o conteúdo de aflatoxina B1foi 30,06 μg/kg.


Assuntos
Aflatoxinas/análise , Aflatoxinas/isolamento & purificação , Aspergillus flavus/isolamento & purificação , Aspergillus flavus/química , Biomassa , Técnicas In Vitro , Pimenta/efeitos adversos , Preparações de Plantas/análise , Preparações de Plantas/efeitos adversos , Cromatografia Líquida de Alta Pressão , Amostras de Alimentos , Métodos , Métodos
15.
Arq. bras. med. vet. zootec ; 60(2): 503-505, abr. 2008.
Artigo em Português | LILACS | ID: lil-484683

RESUMO

The optimization of the thin layer chromatography (TLC) method to determine aflatoxins in feedstuffs and the evaluation of their occurrence in feedstuffs for milk-yielding does in the state of Bahia were studied. Eighty feedstuff samples were collected from five farms, located in the Recôncavo Baiano, from November 2000 to August 2002. The samples were analyzed using TLC modified method. In this study, the detection and quantification limits were 5 and 8m g/kg, respectively. The percentage of average recoveries obtained for AFB1, AFB2, AFG1, and AFG2 were 81.0; 97.2; 89.3; and 90.3 percent, respectively; and the coefficient of variation ranged from 0.83 to 4.1 percent. The results revealed that the optimization of TLC methodology is efficient to analyze aflatoxins in feedstuffs. The presence of these aflatoxins was not detected in any of the analyzed samples, demonstrating good quality of those products, regarding the contamination by these toxins.


Assuntos
Animais , Ração Animal , Aflatoxinas/análise , Cabras , Métodos
16.
Salud pública Méx ; 47(5): 369-375, sept.-oct. 2005. tab
Artigo em Espanhol | LILACS | ID: lil-423260

RESUMO

OBJETIVO: Confirmar el efecto de la nixtamalización tradicional sobre la aflatoxina, identificar el compuesto remanente en masa, evaluar su toxicidad y su regeneración por tratamiento ácido. MATERIAL Y MÉTODOS: Se utilizó maíz, sin y con aflatoxina, y se nixtamalizó. La toxicidad se evaluó en pollos de ocho días de edad. Se aplicó el tratamiento ácido a la masa. La cuantificación de aflatoxinas se realizó por cromatografía líquida de alta resolución (HPLC). RESULTADOS: La nixtamalización destruyó la aflatoxina (96 por ciento) y el aflatoxicol (70 por ciento); el remanente en masa fue aflatoxina B1. El tratamiento ácido in vitro no eleva las concentraciones de ninguna de las dos micotoxinas. Los pollos murieron al ingerir 260 mg de AFB1, y la masa con aflatoxina remanente no fue tóxica. CONCLUSIONES: Los resultados ilustran el beneficio de la nixtamalización tradicional en la inactivación de las aflatoxinas presentes en maíz y en su no reconstitución por efecto del tratamiento ácido.


Assuntos
Aflatoxina B1/antagonistas & inibidores , Aflatoxina B1/toxicidade , Aflatoxinas/antagonistas & inibidores , Manipulação de Alimentos , Venenos/toxicidade , Zea mays , Aflatoxina B1/análise , Aflatoxinas/análise , Concentração de Íons de Hidrogênio , Venenos/análise , Zea mays/química
17.
Indian J Med Sci ; 2005 Aug; 59(8): 331-6
Artigo em Inglês | IMSEAR | ID: sea-68582

RESUMO

BACKGROUND: There are many contaminants like aflatoxin present in food products. Aflatoxin in comparison to many other contaminants is very toxic and also carcinogenic. There are reports of outbreak of aflatoxin toxicity in many parts of the world. AIM: To find out the level of aflatoxin in common food and feed. SETTING: The study was conducted in 16 districts of the Eastern region of Nepal. METHODS AND MATERIALS: Samples were collected from retailers and whole sellers from 1995 to 2003. Common food items that had high chances of infestation were collected. Food sample were taken to the laboratory to estimate the level of aflatoxin. The thin layer chromatography method was used to detect aflatoxin in the samples and comparison of fluorescence of sample spot with fluorescence of standard for estimation. RESULT: There were 832 samples for aflatoxin detection and estimation. One-third samples were found to be contaminated with aflatoxin. The highest percentage of contamination was found in peanut butter/vegetable oil (42.5%) and the lowest in areca nut (25%). Highest proportion of cornflakes samples were found to be contaminated with aflatoxin by more than the recommended value (30 ppb) and contamination in peanut was the lowest. CONCLUSION: People consume many common food items that contain aflatoxin. It is of high importance for the concerned department to give attention to this important public health issue. Even in small doses, continuous consumption can lead to many health problems. So it is of paramount importance to detect and control these contaminants in food items.


Assuntos
Aflatoxinas/análise , Análise de Alimentos , Contaminação de Alimentos , Nepal
18.
Braz. j. microbiol ; 33(2): 138-144, Apr.-Jun. 2002. mapas, tab, graf
Artigo em Inglês | LILACS | ID: lil-330259

RESUMO

Toxigenic fungi were studied in beans (Phaseolus vulgaris L.) of Classes black and color, cultivated in different regions of the State of Santa Catarina, south region of Brazil. The mean counts of filamentous fungi were 2.8 x 103 and 6.7 x 103 CFU/g for beans Classes black and color, respectively. Penicillium spp., Aspergillus spp. and Phoma spp. were the most frequent genera isolated, followed by Ryzopus spp., Alternaria spp., Helminthosporium spp., Cladosporium spp., Botrytis spp., Fusarium spp., Trichoderma spp., Curvularia spp. and Dreschelera spp. Among beans Class black, 24.6 per center of the Aspergillus strains produced mycotoxins: 13.1 per center produced aflatoxins (AFs); 11.5 per center produced ochratoxin A (OTA) and 28.9 per center of Penicillium produced citrinin (CTR). On the other hand, 22.1 per center of Aspergillus strains isolated from beans Class color produced mycotoxins (16.7 per center produced AFs and 5.4 per center produced OTA), while Penicillium genera had 35.4 per center of CTR producing strains. The toxigenic species were A. flavus, A. parasiticus, A. ochraceus and P. citrinum Thom.


Assuntos
Aflatoxinas/análise , Fabaceae , Fungos , Micotoxinas , Métodos , Métodos
19.
Rev. bras. toxicol ; 13(1): 51-4, jul. 2000. tab
Artigo em Inglês | LILACS | ID: lil-271859

RESUMO

The objective of the present work was to analyse nuts, peanuts, almonds and hazelnuts samples to detect the presence of aflatoxins B1 B2 G1 and G2. We also studied the fungic contamination of the above mentioned foodstuffs because fungi the produce the aflatoxins are frequent environmental contaminants the may grow in a wide variety of substrates and under various conditions of humidity, temperature and pH. Therefore, these foodstuffs may suffer a fungic invasion during their production, processing, transportation or storing. Isolated fungi were also studied to find out their capacity for producing toxins in an adequate medium. Out of a total of 100 samples, in two of them, corresponding to peanuts, the presence of Aflatoxin B1 was detected in a concentration of 21 mg/kg and 39 mg/kg respectively. 31 strains of Aspergillus were isolated. 26 isolations correspond to Aspergillus flavus, while 5, to Aspergillus parasiticus. Out of the said 31 strains, 6 were found to produce aflatoxin B in an appropriate culture medium. This allows us to handle more information about the presence of mycotoxins in foodstuffs, to prevent fungic contamination in early stages and alert the public to fungi toxicity.


Assuntos
Aflatoxinas/análise , Arachis/química , Fungos/crescimento & desenvolvimento , Nozes/química , Fungos/isolamento & purificação , Micotoxinas/uso terapêutico
20.
Rev. méd. Panamá ; 25: 4-7, 2000.
Artigo em Espanhol | LILACS | ID: lil-409788

RESUMO

Mycotoxins are fungal metabolites that may contaminate foods and feeds, resulting at times in important disease in humans and animals. Thirty-six samples of nine varieties of newly harvested corn (4 samples each variety) were analyzed in search of aflatoxins by thin layer chromatography and high pressure liquid chromatography, and also cultured for the presence of Aspergillus flavus. Of the 36 samples studied, one was contaminated with 1290 ppb aflatoxin B1, which is 258x the concentration suggested by WHO, placed at 5 ppb in food for human consumption. Culture of the 36 samples of corn resulted in growth of 55 colonies of A. flavus from all but two (1 and 6) of the 9 varieties. Of the 55 colonies of A. flavus obtained, 15 (27.3%) were toxigenic. Comments are made on the public health implications of these findings.


Assuntos
Humanos , Aflatoxinas/análise , Carcinógenos Ambientais/análise , Contaminação de Alimentos/análise , Zea mays/química , Panamá , Zea mays/microbiologia
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