Search results for " Ochratoxin A"
showing 10 items of 10 documents
A polyphasic approach to the identification of ochratoxin A-producing black Aspergillus isolates from vineyards in Sicily.
2008
Aspergillus strains belonging to section Nigri isolated during a two year survey in eight Sicilian vineyards located on the slopes of Mount Etna (Sicily, Italy) were analysed analyzed in order to characterize species responsible for ochratoxin A (OTA) contamination of grapes. The polyphasic approach permitted analysis of biodiversity of Aspergillus isolates in relation to their morphology, ochratoxigenicity and genetic variability. We assessed OTA production by A. carbonarius, A. niger, A. tubingensis and A. japonicus using an enzyme-linked immunosorbent assay. A. carbonarius isolates were the strongest OTA producers. A subset of 66 representative strains was selected for further DNA-based …
Grape and environmental mycoflora monitoring in old, traditionally-cultivated vineyards on Mount Etna, southern Italy
2015
BACKGROUND: Grape contamination by several fungal species occurs during a vineyard's preharvest and harvest. Agronomic management and microclimatic conditions can affect fungi occurrence and epidemiology, thus explaining qualitative differences in mycoflora composition, including the presence of phytopathogenic or mycotoxigenic fungi. In this study a two-year grape, air and soil mycoflora monitoring programme was undertaken in vineyards on Mount Etna (eastern Sicily, Italy). The mycoflora composition was investigated at pea berry and veraison phenological phases from air and soil and at ripening from sample grapes. RESULTS: Mycoflora in air and soil varied according to the phenological stag…
Natural co-occurrence of ochratoxin A, ochratoxin B and aflatoxins in Sicilian red wines
2015
The natural occurrence of ochratoxin A, ochratoxin B, aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 (OTA, OTB, AFB1, AFB2, AFG1, AFG2) in red wines was investigated by HPLC/FLD after immunoaffinity column clean-up in 57 market samples produced in Sicily (Italy). The results showed a very low incidence of these mycotoxins in analysed samples, confirming the high degree of quality and safety of Sicilian red wines. The results indicated 71.9% and 64.9% positive samples for OTA and OTB respectively, with an average level of 0.13 μg l(-1), well below the European maximum permitted levels (MLs). The aflatoxin most frequently detected in the samples was AFG1, present in 57.9% of sample…
Influence of roasting and different brewing processes on ochratoxin A content in coffee determined by high-performance liquid chromatography-fluoresc…
2008
A rapid and reliable procedure has been developed for the determination of ochratoxin A (OTA) in green and roasted coffee. The method consists of extraction of the sample with methanol-5% aqueous sodium hydrogen carbonate/1% PEG8000 (20:80), followed by immunoaffinity column (IAC) clean-up and, finally, high-performance liquid chromatography (HPLC) determination with fluorimetric detection. Mean recoveries for green and roasted coffee spiked at different levels ranging from 94 and 105% were obtained. The limit of determination (S/N = 3) was 0.032 ng g(-1) and the precision (within-laboratory relative standard deviation) was 6%. The method described has been used to assess the influence of r…
Mycotoxin contamination of animal feedingstuff: detoxification by gamma irradiation and reduction of aflatoxins and ochratoxin A concentrations
2014
Mycotoxins are fungal secondary metabolites identified in many agricultural products screened for toxigenic moulds. They have been reported to be carcinogenic, teratogenic, tremorogenic, haemorrhagic and dermatitic to a wide range of organisms. With the increasing stringent regulations for mycotoxins imposed by importing countries such as those of the European Union, many cereals that are not safe for human consumption are used in formulations intended for animal feed. Gamma-rays are reported in the scientific literature to destroy ochratoxin A and aflatoxin in food crops and feed. The present study provides preliminary data for establishing the effect of dose of gamma-irradiation, ranging …
Effect of Gamma Irradiation on Aflatoxins and Ochratoxin A Reduction in Almond Samples
2014
<p>The widespread contamination of food by mycotoxins may present a serious hazard to human and animal health. The gamma rays were applied to reduce ochratoxin A (OTA) and aflatoxins B<sub>1</sub>, B<sub>2</sub>, G<sub>1</sub> and G<sub>2 </sub>(AFB<sub>1</sub>, AFB<sub>2</sub>, AFG<sub>1</sub> and AFG<sub>2</sub>) in almonds artificially contaminated. In the present study we investigated the effect of gamma irradiation dosages, ranging from 0 to 15 kGy and the reduction of mycotoxins concentration in almond samples. In order to determine the efficiency of the method, a high-performance liq…
Microbiological and safety evaluation of green table olives marketed in Italy
2011
The microbiological and safety conditions of green table olives sold on the Italian market were evaluated on 40 samples, 20 loose and 20 packed in containers, purchased at street markets and supermarkets. The olives were analyzed for microflora and food safety indices, and for aflatoxin B1 and ochratoxin A occurrence, and the results showed acceptable security. There was wide heterogeneity in the microflora, the numerical values being in relation to the olive type. The microbial population was dominated by the yeasts and lactic bacteria responsible for the fermentation process, and their numbers, together with the metabolic activity, led to conditions unfavorable for the development of path…
Pressurized liquid extraction coupled to liquid chromatography for the analysis of ochratoxin A in breakfast and infants cereals from Morocco
2010
Abstract A sensitive and reliable method using pressurized liquid extraction (PLE) and liquid chromatography (LC) has been developed for the analysis of ochratoxin A (OTA) in breakfast and infants cereals. Influence of several extraction solvents that affect PLE efficiency was studied. The selected PLE operating method was: 10 g of sample was packed into 22 ml stainless-steel cell and OTA was extracted with acetonitrile/water (80:20) at 40 °C, 34 atm in one cycle of 5 min at 60% flush. The mean recovery of OTA was 82 ± 4 at fortification level of 3 ng/g OTA. The limit of quantification (LOQ) of OTA was 0.25 ng/g. The proposed method was successfully applied to the analysis of 68 samples of …
Bioaccessibility Study of Aflatoxin B1 and Ochratoxin A in Bread Enriched with Fermented Milk Whey and/or Pumpkin
2021
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 bio…
Incidence of grapevine moth Lobesia botrana (Den. & Schif.) on occurrence of ochratoxin A in grapes
2008
Observations were carried out in an organic vineyard (cv malvasia di candia), at salemi (sicily), during 2006-2007, in order to verify the influence of grapevine moth lobesia botrana (den. & schif.) on presence of ochratoxin a (ota) in bunches at harvest time. a percentage of 12.98% of bunches were attacked by grape moth during 2006, while 8.65% of them were infected by grey mould and sour bunch rot (5.77% and 2.88% respectivelly). analyses carried out on 12.98% infested bunches, showed a level of 20 μg/kg of ota, while on intact samples 0.04 μg/kg of toxin was registered. During 2007, infestation of bunches by grape moth was very low (2.05%), due to the particular climatic conditions, and …