首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
《Food Control》2013,31(2):596-601
Peanut cake samples were collected from major markets in five states of Nigeria and evaluated for incidence of toxigenic Aspergillus section Flavi populations, and aflatoxin B1 (AFB1) levels by liquid chromatography tandem mass spectrometry (LC–MS/MS). The awareness of consumers to the presence of aflatoxin in the snack and potential health risks of its regular ingestion was evaluated by questionnaire analysis. Aspergillus section Flavi populations were recovered from 83% of the peanut cake samples. Aspergillus flavus L-strain was the most predominant (>56%) across the states while Aspergillus tamarii had the least mean incidence (2.7%). The incidence of atoxigenic strains was significantly (p < 0.05) higher than that of toxigenic strains in samples from Lagos and Kaduna, while the toxigenic strains had a significantly (p < 0.05) higher incidence than the atoxigenic strains in Niger. All analyzed cake samples contained AFB1 in concentrations exceeding the NAFDAC recommended level for AFB1 in food and reaching up to 2824 μg/kg. There was a weak positive correlation (r = 0.32, p = 0.03) for the relationship between the incidence of toxigenic strains in the samples and AFB1 concentration. The consumer awareness data showed that 64% of the respondents consumed peanut cake; majority of who are youth of economic and reproductive age. Eighty-five percent of the consumers lacked awareness of aflatoxin contamination in the snack and possible health risks associated with its ingestion.  相似文献   

2.
The aim of this study was to determine the levels of the aflatoxins (AFs) and ochratoxin A (OTA) in 312 samples of whole chili, chili powder, crushed chili and chili sauce samples from suburbs, open market and food restaurants of Punjab, Pakistan. The analysis was carried out using HPLC with fluorescence detector, after immunoaffinity column clean-up. The results have shown that 176 out of 312 (56.4%) samples were to be positive with AFs and 126 out of 312 (40.4%) sample of chilies were found to be contaminated with OTA. Total mean level of AFB1 and total AFs in chilies were 12.50 ± 1.91, 15.16 ± 2.22 μg/kg, respectively. The total mean level of OTA in chilies was found 16.68 ± 2.58 μg/kg, ranged from LOD to 120.9 μg/kg. Sample 39.5, 26.3 and 32.7% of chilies were found containing level of AFB1, total AFs and OTA, higher than the recommended limits for EU, respectively. The dietary levels of 3.26, 3.52, and 3.84 μg/kg were determined for AFB1, total AFs and OTA in chilies. The incidence and levels of AFs and OTA in chilies are higher and could pose serious health hazards for consumers.  相似文献   

3.
Studies conducted in Benin, in which the main staple foods are maize, cassava, groundnuts and yams, showed high levels of aflatoxin residues in blood of the exposed population. The natural contamination with fungi and aflatoxins in cassava chips sold at markets in Benin, West Africa was investigated. A total of sixty samples were sampled from open markets in 11 districts of 3 agroecological zones and analyzed for the presence of mycoflora and aflatoxin B1, B2, G1 and G2. Fourteen genera of fungi were associated with marketed dried cassava chips. Within these, twenty- two isolates were identified to species level, whereas four were identified only to genus. The dominating fungal species isolated were Rhizopus oryzae, Nigrospora oryzae, Chrysonilia sitophila, Cladosporium resinae, Cladosporium herbarum, Apergillus niger and Aspergillus flavus. Fifty-four out of sixty samples were contaminated with A. flavus. The rate of occurrence in CFU/g of A. flavus fungi was lower than for all other fungal species together. Aflatoxin was not detected in any of the samples analyzed using HPLC with post-column photochemical derivatization and fluorescence detection. The limit of detection (LOD) was 0.1 μg/kg. Results from this study suggest cassava chips are unlikely to be a source of aflatoxin in Benin, and that other staples such as maize and groundnuts are more important in aflatoxin exposure. Therefore it can be speculated that staples like maize and groundnut are more important in aflatoxin exposure.  相似文献   

4.
Aflatoxin B1 (AFB1) mostly produced by Aspergillus flavus and Aspergillus parasiticus, is an extremely toxic and carcinogenic metabolite. Currants are used in the Mediterranean diet as a food with antioxidant properties. Four strains of Aspergillus section Nigri have been isolated from currants originated from Crete and Corinth. In this study AFB1 production by A. parasiticus and the four strains of Aspergillus section Nigri in Cretan and Corinthian currants (Vitis vinifera L.) is investigated. AFB1 determination was performed by HPLC–FID. Results revealed that the four strains Aspergillus section Nigri, as well as the aflatoxigenic strain A. parasiticus produced AFB1 (0.0052–1.31 μg AFB1 15 g−1, corresponding to 0.0003–0.087 μg AFB1 g−1) in both type of currants (Cretan and Corinthian) on the 12th day of observation. Moreover, AFB1 production, by A. parasiticus in the synthetic Yeast Extract Sucrose (YES) medium was also studied. The ability of AFB1 production has been affected by the special characteristics of each isolate and the currants substrate.  相似文献   

5.
《Food Control》2010,21(7):988-991
Eighty-one rice samples were purchased from different markets in Vienna and were analysed for their aflatoxin content. The samples were extracted using methanol in water (80/20 v/v) followed by immunoaffinity clean up. The determination was carried out by HPLC–FLD coupled to a Kobracell. Different samples including basmati rice, whole grain rice, long grain rice, short grain rice as well as puffed rice were investigated. Moreover, conventionally and organically produced rice were compared. The results revealed that 24 out of 81 samples contained detectable amounts of aflatoxins. Aflatoxin B1 could be quantified in 15 samples and aflatoxin B2 in one sample. The contamination range was noted to be between 0.45 μg kg−1 and 9.86 μg kg−1 for aflatoxin B1 and 1.5 μg kg−1 for aflatoxin B2. Aflatoxins G1 and G2 were not detected in any sample. Three samples exceeded the maximum levels set in the European Union; having AFB1 concentrations of 2.16, 2.85 and 9.86 μg kg−1. In the three organic produced rice samples only traces of aflatoxins were found.  相似文献   

6.
《Food Control》2013,33(2):673-677
A survey in African snacks was carried out in order to evaluate the intake of 23 mycotoxins. The African snack samples were purchased from street vendors within Lagos metropolis (Nigeria) and evaluated for the presence of 23 mycotoxins using a modified QuEChERS procedure coupled with liquid chromatography-triple quadrupole linear ion trap mass spectrometer. The snacks included akara, baked coconut, coconut candy, donkwa, groundnut cake (kulikuli), lafun, milk curd (wara), fresh and dried tiger-nuts, and yam flour. Only three mycotoxins were detected in 23.8% of the studied snacks, and at concentrations ranging from 6 to 54 μg kg−1. The concentrations of aflatoxin B1 (AFB1) and AFB2 reached 23 μg kg−1 and 3 μg kg−1, respectively. Moreover a sample of baked coconut contained α-zearalenol (α-ZOL), which was up to 54 μg kg−1 in coconut candy. As considers prevalence, aflatoxins and α-ZOL were not detected in lafun and groundnut-based snacks (donkwa and kulikuli), whereas each of the three mycotoxins contaminated 12.5% (1/8) of the coconut-based samples. This is the first report of α-ZOL in cassava and coconut, and their products. AFB1 and total aflatoxins (TAFs) concentrations exceeded the maximum allowable limit recommended by National Agency for Food and Drug Administration and Control Nigeria (NAFDAC) in one sample of baked coconut (AFB1 = 23 μg kg−1 and TAFs = 26 μg kg−1) and donkwa (AFB1 = 19 μg kg−1 and TAFs = 21 μg kg−1).  相似文献   

7.
《Food Control》2014,35(2):312-317
When domestic animals are exposed to mycotoxins, significant amounts of the latter shall be carried over into animal products such as milk, eggs and meat. This study was carried out in order to determine the possible presence of aflatoxin B1 (AFB1), ochratoxin A (OTA) and citrinin (CIT) in game sausages (n = 15), semi-dry sausages (n = 25) and fermented dry-meat products (n = 50), randomly taken from individual producers and the Croatian market. AFB1 and OTA were quantified using ELISA, while CIT was quantified using HPLC-fluorescence detector. Out of 90 samples, the fungi most frequently isolated from dry-cured meat products were of Penicillium species, while Aspergillus was isolated from only one sample. As much as 68.88% of the samples were positive for mycotoxins. Finally, the analysis of different types of meat products resulted in OTA identification in 64.44%, CIT identification in 4.44% and AFB1 identification in 10% of the samples. The maximum OTA concentrations established in the commercial sausage samples equalled to 7.83 μg/kg, while that of AFB1 amounted to 3.0 μg/kg. Generally, although OTA was detected in all three types of products in different percentage shares, mutual differences were not statistically significant (P > 0.05).  相似文献   

8.
《Food Control》2007,18(5):454-457
The presence of aflatoxins, Aspergillus flavus and Aspergillus parasiticus in dried fruits was investigated. A total of 62 dried fruit samples were analyzed (24 black sultanas, 19 white sultanas and 19 dried figs). A total of 10 A. flavus isolates were found, nine in one white sultana sample (corresponding to 18% infection) and one isolate in dried figs (2%), and all of them were aflatoxin B1 and B2 producers. A. parasiticus was not found. Aflatoxins were detected in 3 of 19 (16%) white sultana samples analyzed and, the limits were not higher than 2.0 μg/kg. In dried figs 11 of 19 (58%) samples were contaminated with aflatoxins and, with exception of one sample that was contaminated with 1500 μg/kg of B1 aflatoxin, the others had less than 2.0 μg/kg. Neither aflatoxigenic or aflatoxins contaminated black sultanas.  相似文献   

9.
An accurate and rapid LC-ESI-MS/MS analytical method was developed and validated for the simultaneous determination of aflatoxin B1, B2, G1 and G2 in lotus seeds. The samples were firstly extracted with methanol-water solution (80:20, v/v), and then cleaned up by immunoaffinity columns. The mass spectrometer was operated in the positive ionization electrospray (ESI+) mode using multiple reaction monitoring (MRM) for analysis of four aflatoxins. The transitions of m/z 313 → 285 (AFB1, CE 33 eV), m/z 315 → 259 (AFB2, CE 37 eV), m/z 329 → 243 (AFG1, CE 37 eV) and m/z 331 → 257 (AFG2, CE 37 eV) were used to quantify these four aflatoxins, respectively. The limits of detection (LODs) of aflatoxin B1, B2, G1 and G2 were 0.007, 0.005, 0.003 and 0.005 μg kg?1 based on a signal-to-noise ratio of 3:1, respectively. The limits of quantification (LOQs) of aflatoxin B1, B2, G1 and G2 were 0.02, 0.015, 0.01 and 0.015 μg kg?1 based on a signal-to-noise ratio of 10:1, respectively. Recoveries for samples of spiked lotus seeds were all above 66% with relative standard deviation all below 15% for all compounds. Nineteen out of twenty batches of lotus seeds collected from different drug stores or markets in China were found to be contaminated with aflatoxins at different levels ranging from 0.02 to 688.4 μg kg?1.  相似文献   

10.
The aim of this study was to investigate the occurrence of aflatoxin B1 (AFB1) and ochratoxin A (OTA) in different traditional meat products circulating on Croatian markets, produced by a large number of households situated in different Croatian regions. The study involved a total of 410 samples of traditional pork meat products in terms of hams (n = 105), dry fermented sausages (n = 208), bacon (n = 62) and cooked sausages (n = 35), collected over four years period (2011–2014). Mycotoxin concentrations were quantified and confirmed using validated immunoassay method (ELISA) and high performance liquid chromatography with fluorescence detection (HPLC-FLD), respectively. The maximal observed OTA level in the fermented sausages and hams was around 5 times (5.10 μg/kg) to 10 times (9.95 μg/kg) higher than the maximal recommended level (1 μg/kg) stipulated for pork products in some EU countries. AFB1 levels found in any given meat product analysed within this frame were not significantly higher (p > 0.05) than the applied method limit of detection. The results showed an occasional mycotoxin contamination of traditional meat products, especially that by OTA, pointing that to avoid such contamination meat and meat products on households should be produced and processed under standardised and well-controlled conditions.  相似文献   

11.
The feasibility of measuring Aflatoxin B1 (AFB1) in red chili powder was investigated by using Fourier transform near-infrared (FT-NIR) spectroscopy in diffuse reflectance mode combined with appropriate chemometric techniques. Aflatoxin free chili powder samples were spiked with known amount of AFB1 ranging from 15 to 500 μg/kg and used for calibration model building based on partial least squares (PLS) regression algorithm. Different spectral preprocessing methods were investigated and optimized based on the lowest values of root mean square error of cross validation (RMSECV). Spectral wavenumber range of 6900.3–4998.8 and 4902.3–3999.8 cm?1 and straight line subtraction preprocessing technique predicted AFB1 content with best accuracy with lowest RMSECV = 0.654% and maximum correlation coefficient for validation plots (R2 = 96.7). The overall results demonstrate that FT-NIR spectroscopy can be used for rapid, non destructive quantification of Aflatoxin B1 in red chili powder.  相似文献   

12.
《Food Control》2014,35(2):752-755
Aflatoxin M1 (AFM1), the main monohydroxylated of aflatoxin B1 (AFB1) formed in liver and excreted in the milk, has toxicological proprieties comparable to those of AFB1, albeit a lower carcinogenic potency. The presence of AFM1 was investigated in 30 samples of powdered milk purchased in Argentina and Brazil. The samples were analyzed using an immunoaffinity column for cleanup and HPLC-FLD for determining AFM1. The quantification limit was 0.1 μg/kg. AFM1 was found in all the samples at levels ranging from 0.1 to 0.92 μg kg−1 with average concentration of 0.39 μg kg−1.  相似文献   

13.
Detailed investigation on the effect of gamma (γ) irradiation on germination, sporulation, and growth of aflatoxigenic moulds (Aspergillus parasiticus 2999, Aspergillus flavus 305, and Aspergillus niger 388), as well as on the reduction of aflatoxin B1 (AFB1) level in artificially and naturally contaminated maize/feed samples was performed. The results of in vitro and in situ experiments with aflatoxigenic moulds demonstrated that 5 kGy-γ irradiation manages to prevent sporulation, germination and growth of the tested moulds both when in form of a pure and when in form of a mixed culture. In the feed samples artificially contaminated with AFB1 (50 μg kg−1) 5 kGy-γ irradiation reduced AFB1 level by around 60%, while 10 kGy-dose reduce it for around 85%. Similarly, in feed samples spiked with AFB1 in the concentrations of 100 μg kg−1 5 kGy-dose reduced the AFB1 level by approximately 70%, while the dose of 10 kGy reduced it by approximately 90%. The experiments on naturally contaminated maize samples (n = 30) confirmed these observations; following a 5 kGy-irradiation, the overall mean AFB1 reduction equalled to 69.8%, while the irradiation with a 10 kGy-dose achieved the overall mean toxin reduction of 94.5%. The obtained results indicate that γ irradiation can be used to prevent the growth of aflatoxigenic moulds and to reduce the AFB1 levels in various goods intended for animal and human consumption, thus minimizing the animal and human exposure to this carcinogenic mycotoxin.  相似文献   

14.
Aflatoxins primarily accumulate in the hull and bran layers of rough rice making these by-products of rice milling unsuitable for animal feed or human consumption. Contaminated rough rice is also a potential source of aflatoxin exposure to workers handling the grain during post-harvest storage and processing. Currently, no technologies are available to remove or detoxify these toxic and mutagenic fungal metabolites from contaminated rough rice. Pulsed light (PL) is a novel technology with the potential to degrade and detoxify aflatoxins in foods and their processing by-products. Rough rice was inoculated with Aspergillus flavus to produce aflatoxin B1 (AFB1) and B2 (AFB2) contamination, followed by PL treatments of 0.52 J/cm2/pulse for various durations. A PL treatment time of 80 s reduced AFB1 and AFB2 in rough rice by 75.0% and 39.2%, respectively; while a treatment time of 15 s reduced AFB1 and AFB2 in rice bran by 90.3% and 86.7%, respectively. Since PL treatments result in the degradation of aflatoxins in situ, the toxicity and mutagenic activity of the residual by-products of AFB1 and AFB2 after PL treatment were evaluated. Toxicity was estimated using the brine shrimp (Artemia salina) lethality assay and mutagenicity measured by the fluctuation test with Salmonella typhimurum tester strains TA98 and TA100. The mutagenic activity of AFB1 and AFB2 was completely eliminated by PL treatment, while the toxicity of these two aflatoxins was significantly decreased. The obtained results suggest that PL technology has a promising potential to degrade, detoxify, and inactivate the mutagenic activity of aflatoxins in rough rice and rice bran.  相似文献   

15.
Aflatoxin M1 level was measured in 520 milk samples during autumn, winter, spring and summer seasons of 2013–14 in five districts of Southern Punjab-Pakistan. Analyses were performed by using enzyme linked immuno sorbent assay (ELISA) method. Aflatoxin M1 was found positive in 93% milk samples in the range of 0.001–0.26 μg/l while 53% samples were found to exceed the European Union maximum Limit for aflatoxins M1 i.e. 0.05 μg/l. The seasonal prevalence level of AFM1 was found in the order of winter > spring > autumn > summer. Comparing the aflatoxin M1 level during different day times, morning milk was found 37–50% more contaminated than evening milk. The estimated daily intake (EDI) of aflatoxins M1 during different seasons of year for various age groups was found in the range of 0.22–5.45 ng/kg/day. Infants were found in the highest risk group while adults were in the lowest. The results of the study indicate that people of Pakistan are at high risk of health issues related with aflatoxins M1.  相似文献   

16.
The aim of the study was to determine the level of aflatoxin B1 (AFB1) in maize sampled from farms and feed factories situated in Northern, Central and Eastern Croatia during 2013, following the occurrence of cow milk AFM1 contamination. Maize samples (n = 633) were analysed using Enzyme-Linked Immunosorbent Assay (ELISA) as a screening method and High Performance Liquid Chromatography Tandem Mass Spectrometry (LC–MS/MS) as a confirmatory method. Mean AFB1 value found in maize coming from all investigated regions equalled to 81 μg/kg, with the maximal value of 2072 μg/kg found in maize obtained from Eastern Croatia. The observed contamination might have arisen on the grounds of extremely hot (>98%) and dry (<2%) weather witnessed from May to September 2012 during the maize growth and harvesting period, which might have favoured AFB1 production and consequently the contamination of dairy cattle feeds. In order to prevent the adverse effects of AFB1 on humans and animals, and also to reduce losses in agricultural production, systematic monitoring and further investigations of AFB1 contamination are necessary.  相似文献   

17.
Aflatoxin B1 (AFB1), a mycotoxin mainly produced by some Aspergillus species, has been found in a wide range of agricultural products. To avoid the risk of AFB1 consumption, many agricultural commodities, foods and feeds should be analyzed and a rapid and non-instrumental method for the detection of AFB1 is needed. In this study, a rapid, inexpensive and user-friendly latex agglutination inhibition reaction test (LAIRT) for on site testing of AFB1 had been established. At first, carboxylated polystyrene latex particles (CPLP) were prepared by soap-free polymerization and sensitized with aflatoxin B1 oxime-BSA (AFB1O-BSA) for the detection of AFB1. In LAIRT, the agglutination reaction with AFB1O-BSA-sensitized CPLP and anti-AFB1 antiserum mixture was inhibited by 5 ng/mL AFB1 and the analysis time for 6 samples on one glass slide was less than 10 min. Subsequently, 10 rice and peanut samples were analyzed by LAIRT and ELISA, and the results showed that 1 rice sample and 2 peanut samples were positive and in agreement with those of ELISA. However, the results could be obtained more rapidly by LAIRT than ELISA. This easy and rapid LAIRT might be useful for screening AFB1 of agricultural commodities, foods and feeds in the field.  相似文献   

18.
Aflatoxins are a group of carcinogenic compounds produced by Aspergillus fungi that can grow on different agricultural crops. Both acute and chronic exposure to these mycotoxins can cause serious illness. Due to the high occurrence of aflatoxins in crops worldwide fast and cost-effective analytical methods are required for the identification of contaminated agricultural commodities before they are processed into final products and placed on the market. In order to provide new tools for aflatoxin screening two prototype fast ELISA methods: one for the detection of aflatoxin B1 and the other for total aflatoxins were developed. Seven monoclonal antibodies with unique high sensitivity and at the same time good cross-reactivity profiles were produced. The monoclonal antibodies were characterized and two antibodies showing IC50 of 0.037 ng/mL and 0.031 ng/mL for aflatoxin B1 were applied in simple and fast direct competitive ELISA tests. The methods were validated for peanut matrix as this crop is one of the most affected by aflatoxin contamination. The detection capabilities of aflatoxin B1 and total aflatoxins ELISAs were 0.4 μg/kg and 0.3 μg/kg for aflatoxin B1, respectively, which are one of the lowest reported values. Total aflatoxins ELISA was also validated for the detection of aflatoxins B2, G1 and G2. The application of the developed tests was demonstrated by screening 32 peanut samples collected from the UK retailers. Total aflatoxins ELISA was further applied to analyse naturally contaminated maize porridge and distiller's dried grain with solubles samples and the results were correlated with these obtained by UHPLC-MS/MS method.  相似文献   

19.
The natural occurrence of aflatoxins (AFs) and fumonisins (FBs) in yam flour samples (n = 100) obtained in south-western Nigeria was evaluated. AFs were determined by HPLC with fluorescence detection and FBs by HPLC coupled with mass spectrometry. Aflatoxin B1 (AFB1) and aflatoxin G1 (AFG1) were found in 57% and 21% of flours from white yam with concentrations ranging from <0.02 (limit of detection, LOD) to 3.2 μg kg−1 (mean = 0.4 μg kg−1) and from <0.05 to 3.5 μg kg−1, respectively. AFB1 was the only aflatoxin detected in samples from water yam, contaminating 32% of the samples with values ranging from <LOD to 0.6 μg kg−1 (mean = 0.1 μg kg−1). Fumonisin B1 was found in 32% of the white yam samples (<0.5 (LOD) to 91 μg kg−1; mean = 5 μg kg−1) and in 5% of water yam samples (<LOD to 2 μg kg−1). AFs and FBs were significantly higher (P < 0.05) in white yam flours compared to water yam flours. Preparation of amala from naturally-contaminated yam flour resulted in reduction of AFB1 and AFG1 by 44% and 51% respectively. From this study, only 7% of the samples contained AFs above the European standard limits for cereals intended for direct human consumption, while all the FBs-positive samples were well below the limits. The occurrence of ochratoxin A, zearalenone and deoxynivalenol was also evaluated in 20 samples; these mycotoxins were never detected.  相似文献   

20.
Ice-kenkey is a chilled cereal beverage sold as street food in some open markets in Ghana. It is produced by mashing and sweetening kenkey, a stiff dumpling produced from fermented maize meal. The safety of street vended ice-kenkey was assessed by microbiological, elemental and myco-toxicological analysis of ice-kenkey and intermediary products obtained from 16 producers in four open markets in the Accra and Tema metropolis. A tenfold increase in counts of aerobic mesophiles, and yeast and moulds were recorded during the production of ice-kenkey. Coliform bacteria, E. coli and Staphylococcus aureus which were not detected in the starting materials were found partway through production or in the final product. The mean microbial counts in the packaged ice-kenkey were 106–107 CFU/g for aerobic mesophiles, 104–105 CFU/g for yeast and moulds, 10–1000 CFU/g for total coliforms and 10–100 CFU/g for S. aureus. E. coli counts of 10 CFU/g were recorded in samples from three out of the four markets. The microbial load could be eliminated by pasteurizing ice-kenkey at 80 °C for 15 min. The mean concentration in mg/kg of Fe was between 15.97 and 29.48, Cu, 0.57 to 1.41, Mn, 0 to 2.55, Pb 0 to 1.25 and Zn 0.47 to 6.17. Total aflatoxins content in samples ranged from 7.04 to 22.17 μg/kg and included a range of 7.01–20.54 for aflatoxin B1, 0.51 to 1.63 for aflatoxin B2 and 0–0.47 μg/kg for aflatoxin GI. Aflatoxin G2 was not detected in any of the samples. A simplified training module based GMP, GHP and a HACCP plan was developed and used to train ice-kenkey producers in Accra in collaboration with municipal authorities.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号