Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Food Microbiol ; 67: 106-115, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28648287

RESUMO

The objective of this study was to evaluate the biodiversity of Aspergillus section Nigri populations from Cyprus vineyards by morphological, toxigenic and phylogenetic analysis. Aspergillus section Nigri populations were isolated from grapes of the varieties 'Maratheftiko' and 'Cabernet Sauvignon' originating from six growing regions of Cyprus during 2010 and 2011 years. The isolation frequency of Aspergillus section Nigri from grape samples was 43.3% and a total of 284 isolates were selected for further analyses based on the macroscopic characteristics of black aspergilli. The isolates were characterized by sequencing analysis of the calmodulin gene in order to identify species responsible for ochratoxin A (OTA) production. The phylogenetic analysis showed that the isolates were grouped in three major clusters. The A. tubingensis cluster included 262 isolates (92.25%), the A. niger cluster included 15 isolates identified as A. niger (5.3%) and 6 isolates identified as A. welwitschiae (2.1%). One isolate was classified as A. carbonarius (0.35%) and was grouped in a cluster together with the reference isolates of A. carbonarius, A. sclerotioniger, A. sclerotiocarbonarius and A. ibericus. All the isolates were evaluated for their ochratoxigenic ability by HPLC coupled with a fluorescence detector (HPLC-FLD) and the positive isolates were re-examined using ultra high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). The Aspergillus carbonarius isolate produced an average quantity of 1436.1 ng OTA/g Czapek Yeast Agar (CYA); From the A. niger strains three isolates (20%) produced OTA and only one isolate from A. welwitschiae (16.7%) was proved ochratoxigenic with toxin production average at 23.9 ng/g and 9.1 ng/g CYA respectively. Grape must samples derived from the collected berries were also analyzed for OTA and none of the samples were found contaminated with the mycotoxin. The results showed that the geographic area and the meteorological conditions had no significant effect on the incidence and the distribution of black aspergilli in this 2-year project. However, absence of rainfall and low humidity during the harvesting period were critical for the low incidence of the ochratoxigenic A. carbonarius on grapes.


Assuntos
Aspergillus/isolamento & purificação , Biodiversidade , Ocratoxinas/biossíntese , Vitis/microbiologia , Aspergillus/classificação , Aspergillus/genética , Aspergillus/metabolismo , Chipre , Contaminação de Alimentos/análise , Frutas/microbiologia , Filogenia , Vinho/análise
2.
Meat Sci ; 164: 108088, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32092623

RESUMO

The study highlights the investigation of the presence of polycyclic aromatic hydrocarbons (PAHs) in traditionally smoked meat products and charcoal grilled meat. Specifically, the levels of benzo(a)anthracene (BaA), chrysene (Chr), benzo(b)fluoranthene (BbF) and benzo(a)pyrene (BaP) were determined for 262 samples of smoked sausage, bacon, pork (lountza) and ham (chiromeri), grilled pork and poultry produced in Cyprus. The method is based on a saponification and liquid extraction step, followed by solid phase extraction (SPE) cleanup of the extract and finally, the determination of PAHs using high performance liquid chromatography with fluorescence detector. Most of the samples analysed (96%) were contaminated with at least one PAH. In these contaminated samples, 12% of the smoked products and 15% of the grilled meat samples exceeded the maximum levels of the EU legislation. The highest PAH concentrations were found in samples with higher fat content and longer smoking or cooking time.


Assuntos
Carcinógenos/análise , Produtos da Carne/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Galinhas , Culinária/métodos , Chipre , Manipulação de Alimentos/métodos , Fumaça , Suínos
3.
Artigo em Inglês | MEDLINE | ID: mdl-30148685

RESUMO

The determination of acrylamide in potato products, bakery products and coffee, and the human dietary exposure is reported. The method reported is based on a single extraction step with water, followed by the clean-up of the extract using solid phase extraction columns and finally, the determination of acrylamide using UPLC-MS/MS. The MS/MS detection was carried out using an ESI interface in positive ion mode. Internal calibration was used for the quantification of acrylamide, because of the suppression/enhancement matrix effects due to the complex nature of the samples. The method performance characteristics were determined after spiking blank samples. The mean recoveries in spiked coffee samples, potato chips, breakfast cereals and crispbread ranged from 93% to 99%, with RSDs lower than 5% for both repeatability and reproducibility conditions. The estimated limits of detection and quantification of the method were 10 and 32 µg kg-1, respectively. The method was used for monitoring acrylamide in 406 samples. Acrylamide amounts ranged from <32 to 2450 µg kg-1. A total of 360 samples (89%) were contaminated with acrylamide, but only 14% of the samples exceeded the benchmark levels of the EU legislation. Foods with the highest mean acrylamide amounts were potato crisps (642 µg kg-1), French fries (383 µg kg-1) and biscuits (353 µg kg-1). The mean and 95th percentile acrylamide exposures of adolescents in Cyprus were 0.8 and 1.8 µg kg-1 body weight per day, respectively. The estimated levels of dietary exposure to acrylamide are not of concern with respect to neurotoxicity. However, the margins of exposure (MOEs) indicate a concern for carcinogenicity. Potato fried products (45%), fine bakery ware (21%) and potato chips (14%) contributed the most to overall acrylamide exposure.


Assuntos
Acrilamida/análise , Exposição Dietética/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Pão/análise , Cromatografia Líquida de Alta Pressão , Café/química , Chipre , Grão Comestível/química , Humanos , Lanches , Solanum tuberosum/química , Espectrometria de Massas em Tandem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA