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1.
This paper presents 3 years of data (2009–2011) on the occurrence of two mycotoxins, aflatoxin B1 (AFB1) and zearalenone (ZEA), in samples of feedstuff for dairy cows (n?=?963), ewes (n?=?42), and goats (n?=?131) produced in Portugal. AFB1 was found in 15 samples of cow feed (1.6 %), 3 samples of ewe feed (2.3 %) and in 2 samples of goat feed (4.8 %). All but two samples contained AFB1 at levels below the European Union maximum level (5 μg/kg). Nearly half (45 %) of the samples were contaminated with ZEA, but its levels were relatively low, at 5–136.9 μg/kg, well below the European Union guidance value (500 μg/kg).  相似文献   

2.
Twenty-one rice samples from field (ten), store (six) and market (five) from the traditional rice-growing areas of Niger State, Nigeria were analysed for aflatoxins (AFs), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisin B1 (FB1) and B2 (FB2), and patulin (PAT) by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) respectively. T-2 toxin was determined using TLC only. AFs were detected in all samples, at total AF concentrations of 28–372 μg/kg. OTA was found in 66.7% of the samples, also at high concentrations (134–341 μg/kg) that have to be considered as critical levels in aspects of nephrotoxicity. ZEA (53.4%), DON (23.8), FB1 (14.3%) and FB2 (4.8%) were also found in rice, although at relatively low levels. T-2 toxin was qualitatively detected by TLC in only one sample. Co-contamination with AFs, OTA, and ZEA was very common, and up to five mycotoxins were detected in a single sample. The high AF and OTA levels as found in rice in this study are regarded as unsafe, and multi-occurrences of mycotoxins in the rice samples with possible additive or synergistic toxic effects in consumers raise concern with respect to public health.  相似文献   

3.
The aim of this study was to investigate the contamination of pig feed with moulds and the occurrence of mycotoxins. A total of 30 feed samples were collected at different animal feed factories in the north-western part of Croatia. Mycological analysis showed that the total number of moulds ranged from 1?×?103 to 1?×?105?cfu/g with samples contaminated with Aspergillus spp. (63?%), Penicillium spp. (80?%), and Fusarium spp. (77?%). A determination of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), T-2 toxin (T-2) and fumonisin (FUM) concentration was done using the validated ELISA method. The mean concentrations of AFB1 (0.5?±?0.6???g/kg), OTA (1.53?±?0.42???g/kg) and FUM (405?±?298???g/kg) were below the maximum levels or recommended values in the EU in all the investigated samples. The observed results indicated an increased contamination of pig feed with Fusarium mycotoxins DON and ZEA with mean concentrations of 817?±?447 and 184?±?214???g/kg, higher than recommended in 40 and 17?% of the analysed samples, respectively.  相似文献   

4.
A survey of aflatoxins in sesame in Iran   总被引:1,自引:0,他引:1  
A study of the occurrence of aflatoxins (AF) in sesame seeds was conducted in the Khorasan province of Iran between September 2009 and August 2010. Samples (n = 182) were analyzed by liquid chromatography (LC), and detection limits for AFB1, AFB2, AFG1 and AFG2, were 0.45, 0.19, 0.61, and 0.22 ng/g, respectively. AFB1 was detected in 33 samples (18.1%), at a mean level of 1.62 ± 1.32 ng/g, and a maximum level of 5.54 ng/g. AFB1 levels exceeded the European Union (EU) maximum tolerated level (MTL, 2 ng/g) in 9 samples, and the Iran MTL (5 ng/g) in 1 sample. Regarding total aflatoxins (AFT), the mean level was 0.92 ± 1.36 ng/g, and the maximum level was 5.54 ng/g. No sesame sample exceeded the Iran MTL (15 ng/g), but two samples exceeded the EU MTL (4 ng/g) for AFT. It is concluded that low levels of AFs occur frequently in sesame from Iran.  相似文献   

5.
The influence of inoculum size on the colony-forming units, production of aflatoxin B1 (AFB1) and ochratoxin A (OTA) was determined when Aspergillus flavus and A. niger aggregate strains were cultured alone and in pairs on irradiated peanut grains at 28°C and 0.97 water activity (aW). The results showed a marked influence of inoculum factor on fungal counts, AFB1 and OTA production in single and paired cultures. Fungal counts of the A. niger aggregate strain in interacting cultures at 7, 14 and 21?days of incubation were significantly higher than those observed in the A. flavus strain, except in the mixed culture with 102 spores/ml of both strains. In all mixed culture assays, the AFB1 production was significantly reduced in comparison with the accumulation of mycotoxin in single cultures. A total inhibition in AFB1 production was observed in some interactions as 102 spores/ml of A. flavus and 103 spores/ml of A. niger aggregate strain at 7 and 14?days, among others. With regard to OTA production, a stimulation in the interacting cultures was observed at all inoculum sizes and incubation period. The highest levels of OTA accumulation were observed at 14?days for all interacting cultures. The maximum level was reach in the culture 103 spores/ml of A. niger aggregate and 104 spores/ml of A. flavus (p?<?0.001). These results suggest that, under optimal environmental conditions in peanut grains, the interaction between A. flavus and A. niger aggregate strains could result in an inhibition of AFB1 and in a stimulation of OTA production.  相似文献   

6.
Mycotoxin contamination of pistachios represents a serious food safety hazard. The aim of this study was to evaluate fungal contamination and aflatoxin (AF) and ochratoxin A (OTA) occurrence in pistachio sampled in Algeria and to study the mycotoxigenic capacities of the isolates. A total of 31 pistachio samples were collected from retail outlets from different regions of Algeria. The most frequently found fungi were Penicillium spp. (38%), Aspergillus section Nigri (30%) and A. flavus (22%). A total of 56.5% of A. flavus isolates were able to produce AFB1 and AFB2. No A. section Nigri uniseriate isolate was OTA producer, whereas OTA production capacity was detected in 33.3% of the A. section Nigri biseriate. At least one of the potentially ochratoxigenic species was found in 64.5% of samples. Despite the high number of pistachio samples containing AFs and OTA-producing isolates, only two samples contained AFs (always below the EU maximum tolerable level) and only one sample showed OTA contamination. This is the first report on the occurrence of toxigenic moulds and mycotoxins in pistachios from Algerian market.  相似文献   

7.
Alternaria alternata, A. tenuissima, Fusarium graminearum, F. semitectum, F. verticillioides, Aspergillus flavus, and Aspergillus section Nigri strains obtained from blueberries during the 2009 and 2010 harvest season from Entre Ríos, Argentina were analyzed to determine their mycotoxigenic potential. Taxonomy status at the specific level was determined both on morphological and molecular grounds. Alternariol (AOH), alternariol monomethyl ether (AME), aflatoxins (AFs), zearalenone (ZEA), fumonisins (FBs), and ochratoxin A (OTA) were analyzed by HPLC and the trichotecenes deoxynivalenol (DON), nivalenol (NIV), HT-2 toxin (HT-2), T-2 toxin (T-2), fusarenone X (FUS-X), 3-acetyl-deoxynivalenol (3-AcDON), and 15-acetyl-deoxynivalenol (15-AcDON) by GC. Twenty-five out of forty two strains were able to produce some of the mycotoxins analyzed. Fifteen strains of Aspergillus section Nigri were capable of producing Fumonisin B1 (FB1); two of them also produced Fumonisin B2 (FB2) and one Fumonisin B3 (FB3). One of the F. graminearum isolated produced ZEA, HT-2, and T-2 and the other one was capable of producing ZEA and DON. Two A. alternata isolates produced AOH and AME. Four A. tenuissima were capable of producing AOH and three of them produced AME as well. One Aspergillu flavus strain produced aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), and aflatoxin G1 (AFG1). To our knowledge, this is the first report showing mycotoxigenic capacity of fungal species isolated from blueberries that include other fungi than Alternaria spp.  相似文献   

8.
Aflatoxin B1 (AFB1) is a carcinogenic metabolite produced by certain Aspergillus species such as A. parasiticus and A. flavus. The beneficial properties of bee pollen have transformed this commodity into an increasingly frequent component of the human diet. As bee pollen is a substrate on which aflatoxigenic fungi can grow, AFB1 production is likely. In the present study, we describe a method for aflatoxin B1 determination in bee pollen utilising high pressure liquid chromatography (HPLC) with a fluorescence detector (FD). The recovery factor of the method was found to be 111% (RSD% 1.61), while the detection limit (LOD) was 0.08 ng AFB1/g. An additional aim of this study was to investigate the growth of A. parasiticus and AFB1 production in bee pollen. Results indicated that no mycelial growth was observed and no AFB1 was detected in bee pollen samples containing natural microbiota throughout the entire observation period (20 days). In contrast, AFB1 production in treated bee pollen samples (15 g pollen/flask) inoculated with A. parasiticus was significantly higher (p?≤?0.05) compared to control samples (treated but not inoculated) throughout the entire incubation period, while no mycelial growth was apparent. Maximum production was observed on the 12th day (79.29 ng AFB1/flask and 32.44 ng AFB1/flask for inoculated and non-inoculated bee pollen, respectively). As a result, AFB1 production in bee pollen is likely even following a minor contamination, which could occur randomly.  相似文献   

9.
Samples from large (100–200 tons) batches of palm kernel cake (PKC, n?=?20) and copra meal (CM, n?=?13) were collected at production facilities of four Indonesian feed mill manufacturers and analysed for aflatoxin B1 (AFB1) by ELISA. Recoveries using spiked samples ranged from 86 to 113 %, with relative standard deviations of <9 % (PKC) and <6 % (CM). All batches were positive for AFB1: in PKC, at levels of 5.8–93.1 μg/kg (mean 49 μg/kg), and in CM, at levels of 1.1–147 μg/kg (mean 38.1 μg/kg). AFB1 levels were, in most batches, below the maximum level (100 μg/kg) recommended by the National Standardisation Agency, Republic of Indonesia. However, about half of the batches exceeded both the European Union and USA regulations for AFB1 in animal feed. In conclusion, serious efforts are necessary to control production, storage and shipment of palm kernel cake and copra meal for feed purposes, and clearly not only for products intended for export but also to reduce AFB1 levels in domestic Indonesian feed.  相似文献   

10.
An extensive survey of filamentous fungi isolated from wheat grown and consumed in Lebanon and their capacity to produce aflatoxin B1 (AFB1) and ochratoxin A (OTA) was conducted to assess fungi potential for producing these toxins in wheat. From the 468 samples of wheat kernel, collected at preharvest stage from different locations during 2008 and 2009 cultivation seasons, 3,260 fungi strains were isolated with 49.4% belonging to Penicillium spp. and 31.2% belonging to Aspergillus spp. Penicillium spp. was detected on wheat samples with a high amount of P. verrucosum (37.0%). Among the different Aspergillus spp. isolated, A. niger aggregate was predominant and constituted 37.3%. whereas the isolation rate of A. flavus and A. ochraceus was 32.2 and 25.6%, respectively. The ability to produce OTA and AFB1 by isolates belonging to Aspergillus spp. and Penicillium spp. was analyzed by high performance liquid chromatography with fluorescence detector (HPLC-FLD). It was found that 57.0% of Penicillium spp. and 80% of A. ochraceus isolates tested produced OTA, respectively, at maximum concentrations of 53 and 65 μg/g CYA. As for the aflatoxinogenic ability, 45.3% of A. flavus produced AFB1, with maximum concentration of 40 μg/g CYA. A total of 156 wheat samples were analyzed for the levels of OTA and AFB1 by HPLC-FLD. The results showed that 23.7% were contaminated with OTA, at a concentration higher than 3 μg/kg and 35.2% of these samples were contaminated with AFB1 at concentration higher than 2 μg/kg. The risks originating from toxin levels in wheat produced in Lebanon should be monitored to prevent their harmful effects on public health.  相似文献   

11.
A comparison was made of total aflatoxins (AFs) in 43 samples of chilies collected during winter and 42 in summer to determine the effect of season on contamination. The samples were analyzed by HPLC with fluorescence detection. The limits of detection and quantification for AFB1 and AFG1 were 0.05 μg/kg and 0.50 μg/kg, whilst for AFG2 and AFB2 they were 0.10 μg/kg and 0.60 μg/kg. In the winter samples, AFs were detected in 18 (72%) whole and 14 (60%) ground chilies, with concentration ranges 0.00-52.30 μg/kg and 0.00-74.60 μg/kg respectively. In the summer samples, 17 (64%) whole and 12 (76%) ground chilies were contaminated with AFs at concentrations 0.00-61.50 μg/kg and 0.00-95.90 μg/kg respectively. The percentage of samples greater than the European Union statutory limit for AFB1 and total AF for whole chilies were 48 and 36%, compared with ground chili values of 50 and 45%, respectively, in the winter season. In the summer season, the samples greater than the European Union limit for AFB1 and total AF in whole chilies were 52 and 38%, compared with values of 54 and 49% in ground chilies respectively. AF contamination was found to be higher in summer chili samples and hence winter chilies may provide a better quality product with respect to AF contamination. The ability to undertake this analysis in Pakistan will enhance greatly the ability to improve chili production in that country, as described herein.  相似文献   

12.
A novel and sensitive immunoassay for the simultaneous detection of aflatoxin B1 (AFB1) and ochratoxin A (OTA) in food samples was developed by using artificial antigen-modified magnetic nanoparticles (MNPs) as immunosensing probes and antibody functionalized upconversion nanoparticles (UCNPs) as signal probes. NaY0.78F4:Yb0.2, Tm0.02 and NaY0.28F4:Yb0.7,Er0.02 UCNPs were prepared and functionalized, respectively, with immobilized monoclonal anti-AFB1 antibodies and anti-OTA antibodies as signal probes. Based on a competitive immunoassay format, the detection limit for both AFB1 and OTA under optimal conditions was as low as 0.01 ng mL−1, and the effective detection range was from 0.01 to 10 ng mL−1. The proposed method was successfully applied to measure AFB1 and OTA in naturally contaminated maize samples and compared to a commercially available ELISA method. The high sensitivity and selectivity of this method is due to the magnetic separation and concentration effect of the MNPs, the high sensitivity of the UCNPs, and the different emission lines of Yb/Tm and Yb/Er doped NaYF4 UCNPs excited by 980 nm laser. Multicolor UCNPs have the potential to be used in other applications for detecting toxins in the field of food safety and other fields.  相似文献   

13.
Forty-three peanut butter samples from Khartoum State, Sudan, were analyzed for aflatoxins (AFs, AFB1 + AFB2 + AFG1 + AFG2) using high performance liquid chromatography (HPLC) with fluorescence detection after extraction with methanol:water (8:1, v/v) and clean-up using chloroform. All samples were contaminated with AFs, with total AF levels ranging between 26.7 and 853 μg/kg, and a mean total AF level of 287 ± 200.5 μg/kg. The highest concentrations were found for AFB1, (28 positive samples, maximum 534 μg/kg), while AFG1 was most frequently detected (43 positive samples, maximum 401 μg/kg). AFB2 (42 positive samples, maximum 3.2 μg/kg) and AFG2 (4 positive samples, maximum 30 μg/kg) were also present in these samples. The mean AF contamination levels found in this study exceeded by far all international regulations concerning maximum levels for this group of toxins. From the data, it is concluded that the levels of AF contamination in peanut butter from the Kartoum area are quite alarming, and may pose serious health hazards to consumers. Therefore, an intervention strategy to manage AF in peanut butter is urgently needed.  相似文献   

14.
Aims: To determine incidence and levels of ochratoxin A (OTA) in California raisins and to isolate and characterize OTA‐producing fungi from California raisin vineyard populations. Methods and Results: Forty raisin clusters sampled from four California vineyards in the San Joaquin Valley were analysed for OTA content using immunoaffinity and HPLC methods. OTA was detected in 93% of the samples, at levels from 0·06 to 11·4 ng g?1. From these raisin samples, a total of 400 strains of Aspergillus were isolated and analysed for OTA production. Twelve isolates (3%), from five raisin samples, produced OTA. These isolates were identified as Aspergillus carbonarius, based on morphological characteristics and multilocus sequence analysis. Levels of OTA produced by these isolates on raisin agar ranged from 0·9 to 15 μg g?1. Conclusions: OTA is a common contaminant of raisin vineyards, but average levels are much lower than EU regulatory limits for dried fruit. The primary species responsible for OTA contamination in California raisins is A. carbonarius. Significance and Impact of the Study: This study illustrates that low‐level OTA contamination of raisins occurs in California and that ecological studies of A. carbonarius within the Aspergillus section Nigri population on raisins are warranted to monitor ochratoxigenic potential of the crop.  相似文献   

15.
Humans are constantly exposed to mycotoxins (e.g. aflatoxins, ochratoxins), mainly via food intake of plant and animal origin. The health risks stemming from mycotoxins may result from their toxicity, in particular their carcinogenicity. In order to prevent these risks, the International Agency for Research on Cancer (IARC) in Lyon (France)—through its IARC Monographs programme—has performed the carcinogenic hazard assessment of some mycotoxins in humans, on the basis of epidemiological data, studies of cancer in experimental animals and mechanistic studies. The present article summarizes the carcinogenic hazard assessments of those mycotoxins, especially aflatoxins (aflatoxin B1, B2, G1, G2 and M1), fumonisins (fumonisin B1 and B2) and ochratoxin A (OTA). New information regarding the genotoxicity of OTA (formation of OTA-DNA adducts), the role of OTA in oxidative stress and the identification of epigenetic factors involved in OTA carcinogenesis–should they indeed provide strong evidence that OTA carcinogenicity is mediated by a mechanism that also operates in humans–could lead to the reclassification of OTA.  相似文献   

16.
Aflatoxin-lysine (AFB1-lys) adduct levels in blood samples collected from 230 individuals living in three districts of Malawi (Kasungu, Mchinji, and Nkhotakota) and aflatoxin B1 (AFB1) levels in groundnut and maize samples collected from their respective homesteads were determined using indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) methods. AFB1-lys adducts were detected in 67% of blood samples, with a mean concentration of 20.5?±?23.4 pg/mg of albumin. AFB1 was detected in 91% of groundnut samples and in 70% of maize samples, with mean AFB1 levels of 52.4 and 16.3 μg/kg, respectively. All participants of this study reported consuming maize on a daily basis and consuming groundnuts regularly (mean consumption frequency per week: 3.2?±?1.7). According to regression analysis, a frequency of groundnut consumption of more than four times per week, being female, and being a farmer were significant (p?<?0.05) contributors to elevated AFB1-lys adduct levels in the blood. This is the first report on AFB1-lys adducts in blood samples of residents in Malawi. The results reinforce the urgent need for interventions, aiming at a reduction of aflatoxin exposure of the population.  相似文献   

17.
Aims: To evaluate mycobiota and aflatoxins B1 (AFB1), B2 (AFB2), G1 (AFG1), G2 (AFG2) and fumonisin B1 (FB1) contamination in different malted barley types and brands and brewer’s grain collected from a major Argentinean brewery. Methods and Results: Total fungal counts were performed using the plate count method. Aflatoxin B1, AFB2, AFG1, AFG2 and Zearalenone (ZEA) analyses were performed by thin‐layer chromatography (TLC). Fumonisin B1 was determined by HPLC. Eighty‐three percentage of the malted barley (100% M1, 50% M2 and 100% M3) and 61% of brewer’s grain samples had a count >1 × 104 CFU g?1. Yeasts were isolated from all malt and brewer’s grain samples. Genera containing some of the most important mycotoxin producer species –Fusarium ssp., Aspergillus ssp., Penicillium ssp. and Alternaria ssp. – were isolated from the analysed samples, along with other environmental saprophytic fungi such as Geotrichum ssp., Mucorales and Cladosporium ssp. All samples were contaminated with 104–145 μg kg?1 FB1. Eighteen per cent of brewer’s grain samples were contaminated with 19–44·52 μg kg?1 AFB1. Aflatoxin B2, AFG1, AFG2 and ZEA were not detected in any of the analysed samples. Conclusions: Fungal and mycotoxin contamination in malt and brewer’s grain is an actual risk for animal and human health. Significance and Impact of the Study: This study may be useful for assessing the risk of mycotoxins in Argentinean beers and especially in animal feeds.  相似文献   

18.
Eighty-five samples of cocoa products sampled in Canada were analysed for ochratoxin A (OTA) and aflatoxins in 2011–2012. Inclusion of the aflatoxins in this survey required additional method development. Chocolate was extracted with methanol–water plus NaCl, while for cocoa two successive extractions with methanol and methanol–water were made. Extracts were cleaned on an AflaOchra immunoaffinity column (IAC). Determination was by reversed phase high performance liquid chromatography (HPLC). Detection of the aflatoxins was with a post-column photochemical reactor and of OTA by fluorescence detection. Mean limits of quantification (LOQ) of chocolate and cocoa powders were 0.16 ng/g (OTA) and 0.07 ng/g (aflatoxin B1), respectively. Survey results showed that the incidences of OTA above the LOQ in natural cocoa were 15/15 (mean 1.17 ng/g), 20/21 for alkalized cocoa (mean 1.06 ng/g), 9/9 for baking chocolate (mean 0.49 ng/g), 20/20 for dark chocolate (mean 0.39 ng/g), 7/10 for milk chocolate (mean 0.19 ng/g), 5/5 for cocoa liquor (mean 0.43 ng/g), and 0/5 for cocoa butter. These results confirm our previous work with OTA. In the same samples, incidences of aflatoxin B1 above the LOQ were 14/15 for natural cocoa (mean 0.86 ng/g), 20/21 for alkalized cocoa (mean 0.37 ng/g), 7/9 for baking chocolate (mean 0.22 ng/g), 16/20 for dark chocolate (mean 0.19 ng/g), 7/10 for milk chocolate (mean 0.09 ng/g), 4/5 for cocoa liquor (mean 0.43 ng/g), and 0/5 for cocoa butter. Both aflatoxins and OTA were confirmed by HPLC-MS/MS when OTA or aflatoxin levels found were above 2 ng/g in cocoa.  相似文献   

19.
Ochratoxin A (OTA) is a mycotoxin produced mostly by several species of Aspergillus and Penicillium. OTA is nephrotoxic in all animal species in which it has been tested and is cancerogenic in rodents. It is associated with Balkan endemic nephropathy. It is naturally present in many crop products such as cereals (barley, wheat, maize) and dried fruits, spices, coffee, wine, olives, and cocoa. The aim of this study was to assess the contamination of three Ivoirian spices with OTA (ginger, chili, and pepper) widely consumed by the population. A total of 90 spice samples (ginger: n?=?30; chili: n?=?30; pepper n?=?30) was taken from various sales outlets of Abidjan. OTA was quantified using an HPLC apparatus coupled with a fluorimetric detector. The chili and ginger samples were contaminated with OTA at a mean concentration of 57.48?±?174 and 0.12?±?0.15 μg/kg, respectively. No contamination of the pepper samples was detected. Eight (26.67 %) of the chili samples exceeded the maximum limit of 15 μg/kg established by European regulation. These results should serve as an alert on the risk to the consumer population of these products that are highly contaminated with OTA.  相似文献   

20.
Fourteen barley and nine corn samples, destined for animal feed, collected from Golestan and Mazandaran provinces in the north of Islamic Republic of Iran (I. R. Iran) were analysed for aflatoxins (AF) and ochratoxin A (OA) by high performance liquid chromatography. In corn samples, aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) were detected in 8 (88.8%) and 6 (66.6%) samples at a mean level of 15.83 and 2.99 ppb (median 1.72 and 1 ppb), respectively. None of the corn samples contained detectable amounts of aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2). Only one of the AF-contaminated samples was co-contaminated with OA at a concentration of 0.35 ppb. This is the first report concerning natural occurrence of OA and co-occurrence with AF in corn samples of north of I. R. Iran.  相似文献   

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