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1.
A survey for total aflatoxins (aflatoxins B1, B2, G1, and G2) was conducted on 88 spices and processed spice products commercialized in Korea. The presence of aflatoxins was determined by high-performance liquid chromatography (HPLC) with fluorescence detector using immunoaffinity column clean-up. Total aflatoxins (AFs) are detected in 12 samples (13.6% of incidence) including seven red pepper powder, two red pepper pastes (Kochujang), two curry and one ginger product. The contamination levels are 0.08–4.45 μg/kg as aflatoxin B1 and 0.08–4.66 μg/kg as AFs. The liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis on contaminated samples was conducted for the confirmation of detected aflatoxins. The 12 samples which showed aflatoxins by HPLC/FLD were confirmed as aflatoxins by LC–MS/MS.  相似文献   

2.
Consumption of mycotoxin contaminated foodstuffs is common in regions where foods are not adequately controlled and routinely monitored, and this could have adverse effects on the health of consumers. In this study, 100 samples of roasted nuts (50 cashew nuts and 50 peanuts) vended within two cities of Sierra Leone were analysed for mycotoxins and other microbial metabolites by a LC-MS/MS method. The peanut samples contained detectable levels of 17 microbial metabolites, including aflatoxins B1, B2, G1 and G2 and alternariol, while none of these metabolites were found in the cashew samples. Aflatoxins (max: 5,729 μg/kg; mean: 487.8 μg/kg) and alternariol (3 μg/kg) were found in 24% and 2% of the peanut samples, respectively. One-third of the aflatoxin-contaminated peanut samples contained aflatoxins at levels exceeding the total aflatoxin limit of 4 μg/kg set by the European Union. Aflatoxin contamination of Sierra Leonean peanuts is high and requires urgent intervention to reduce consequent exposure.  相似文献   

3.
An easy and quick sample pretreatment method, air-assisted dispersive liquid–liquid microextraction (AA-DLLME), has been introduced for the isolation and enrichment of aflatoxins B1, B2, G1, and G2 from rice samples prior to HPLC-FLD analysis. The method has also been compared with immunoaffinity column clean-up (IAC) method. In the case of AA-DLLME, the dispersion of extractant is formed in the absence of a disperser solvent and with the help of air bubbles. Several crucial factors, including the volume and type of extraction solvent, the volume of aqueous phase, and the number of extraction cycles were studied to obtain the optimal conditions. Under the optimal conditions, the suggested technique showed linearity in the range of 0.08–10 ng/mL with low limits of detection (0.68, 0.68, 0.13, and 0.13 ng/g for aflatoxins B1, G1, B2, and G2, respectively) and good sensitivity with limits of quantification of 2.0, 2.0, 0.4, and 0.4 ng/g for aflatoxins B1, G1, B2, and G2, respectively. The proposed procedure was successfully used to evaluate aflatoxins (AFs) in rice samples and acceptable recoveries in the range of 76.0–109.3% with appropriate precision (RSD?<?14.2%) were obtained.  相似文献   

4.
The occurrence of aflatoxin (aflatoxin B1, aflatoxin B2, aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2)) and heavy metal (Pb, Cd, As and Hg) contamination was determined in 40 industrially produced animal feed samples which were collected from the southwest of Iran. The results indicated that 75% of samples were contaminated by four aflatoxins and the level of AFB1 and sum of aflatoxins were higher than the permissible maximum levels in Iran (5 and 20 µg kg?1, respectively) in all feed samples. A positive correlation was found between four types of aflatoxins in all the tested samples (p < 0.01) and the positive correlation between AFG1 and AFG2 was significant (r2 = 0.708). All feed samples had lead concentrations lower than the maximum EU limit, while 5%, 17% and 42.5% of feed samples had As, Cd and Hg concentrations higher than the maximum limits, respectively.  相似文献   

5.
This study presents a method validation procedure for the determination of aflatoxin B1, B2, G1, and G2 in hazelnut, hazelnut paste, walnut, peanut, pistachio, corn, and wheat. The method consisting of clean-up with immunoaffinity column, high performance liquid chromatography with postcolumn derivatization and fluorescence detection was validated in accordance with Commission Regulation 2004/882/EC. The selectivity, linearity, decision limit, detection capability, detection and quantification limits, precision, recovery, ruggedness, and measurement uncertainty of the method were determined. The limit of detection and limit of quantification values (μg/kg) were: aflatoxin B1, 0.02, 0.07; aflatoxin B2, 0.01, 0.02; aflatoxin G1, 0.02, 0.07; and aflatoxin G2, 0.01, 0.03. The relative standard deviation values for the repeatability and within-laboratory reproducibility were below 4 and 5 %, respectively. The recovery values of the spiked samples ranged from 80 to 105 %. These results complied with minimum performance criteria established by regulation 2006/401/EC. Therefore, the procedure can be implemented for the routine analysis of aflatoxins in the studied matrices.  相似文献   

6.

ABSTRACT

The main focus of our study was to implement a rapid, inexpensive and reliable method that could be utilized to check the cereals for safety (i.e., screening for total aflatoxins, as well as individual B1, B2, G1, G2 aflatoxins and ochratoxin A). We developed a protocol by which we were able to isolate mycotoxins from cereals collected from different regions of Romania. After extraction in chloroform, the mycotoxins were separated by thin‐layer chromatography (TLC) and quantified using densitometry. Forty‐three samples of different cereals (wheat, maize, rye and Triticale) were analyzed. Twenty‐five of the 43 samples (58.14% of the total number) were found to be contaminated with different mycotoxins in various concentrations: aflatoxin B1 (1.6–5.7 µg/kg), aflatoxin B2 (0.89–4 µg/kg), aflatoxin G1 (1.2–5.76 µg/kg), aflatoxin G2 (0.96–3.4 µg/kg) and/or 4.3–30 µg/kg ochratoxin A. The concentration of total aflatoxin contamination ranged from 11.2 to 10.8 µg/kg. Among the different cereals, the highest number of contaminated samples was found to be in the wheat samples (62.5%). The method outlined in this study has been adopted already by our laboratory for current analyses of mycotoxins. The results obtained using this method is in compliance with the strict regulatory guidelines developed both in Romania, as well as in the European Union.

PRACTICAL APPLICATIONS

Thin‐layer chromatography (TLC) is a rapid, inexpensive and convenient method that can be used routinely to screen for mycotoxins. This article describes the detailed procedures for the extraction, purification and quantification of aflatoxins and ochratoxin A, using TLC. Using this method one can identify concomitantly five different mycotoxins and by coupling it with densitometry a quantitative determination is also possible. Therefore, this could become a routine technique in regional laboratories responsible for checking agrifood safety.  相似文献   

7.
ABSTRACT

A simple and rapid method for the simultaneous determination of 11 mycotoxins – aflatoxins B1, B2, G1 and G2; fumonisins B1, B2 and B3; ochratoxin A; zearalenone; deoxynivalenol; and T-2 toxin – in edible oils was established using liquid chromatography tandem mass spectrometry (LC-MS/MS). In this study, QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe), QuEChERS with dispersive liquid–liquid microextraction, and solvent extraction were examined for sample preparation. Among these methods, solvent extraction with a mixture of formic acid/acetonitrile (5/95, v/v) successfully extracted all target mycotoxins. Subsequently, a defatting process using n-hexane was employed to remove the fats present in the edible oil samples. Mass spectrometry was carried out using electrospray ionisation in polarity switching mode with multiple reaction monitoring. The developed LC-MS/MS method was validated by assessing the specificity, linearity, recovery, limit of quantification (LOQ), accuracy and precision with reference to Commission Regulation (EC) 401/2006. Mycotoxin recoveries of 51.6–82.8% were achieved in addition to LOQs ranging from 0.025 ng/g to 1 ng/g. The edible oils proved to be relatively uncomplicated matrices and the developed method was applied to 9 edible oil samples, including soybean oil, corn oil and rice bran oil, to evaluate potential mycotoxin contamination. The levels of detection were significantly lower than the international regulatory standards. Therefore, we expect that our developed method, based on simple, two-step sample preparation process, will be suitable for the large-scale screening of mycotoxin contamination in edible oils.  相似文献   

8.
This research aimed at evaluating the safety, and the type, level and prevalence of mycotoxins in grain sorghum of four sub-Saharan African (SSA) countries (Burkina Faso, Ethiopia, Mali and Sudan). A multi-analyte LC-MS/MS method for quantification of 23 mycotoxins (nivalenol, deoxynivalenol, fusarenon X, neosolaniol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, diacetoxyscirpenol, roquefortine C, HT-2 toxin, alternariol, T-2 toxin, FB1, FB2, FB3, zearalenone, aflatoxin G1, aflatoxin G2, aflatoxin B1, aflatoxin B2, sterigmatocystin, OTA, altenuene, alternariol monomethylether) was applied to different sorghum matrices. Of the 1533 analysed samples, 33% were contaminated with at least one of the following mycotoxins: aflatoxins, fumonisins, sterigmatocystin, Alternaria toxins, OTA and zearalenone. Country of origin, colour, source and collection period of sorghum samples significantly influenced the type, level and prevalence of mycotoxins. Sterigmatocystin (15%), fumonisins (17%) and aflatoxins (13%) were the most prevalent. FB1 (274 ± 585 µg/kg) had the highest mean concentration followed by FB2 (214 ± 308 µg/kg) while diacetoxyscirpenol (8.12 ± 19.2 µg/kg) and HT-2 (11.9 ± 0.00 µg/kg) had the lowest concentrations. Neosolaniol, fusarenon-X, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, T-2 toxin, nivalenol and roquefortine C were not detected in any of the samples. Sudan had the lowest prevalence and mean concentration of all mycotoxins. Pink sorghum had the highest concentrations of fumonisins and aflatoxins. Mycotoxins from Aspergillus spp. and Alternaria spp. are the mycotoxins of concern in SSA grain sorghum with regard to prevalence, concentration and possible health risk from exposure. Based on the performed risk characterisation, daily consumption of sorghum containing aflatoxins, alternariol, alternariol monomethyl ether, sterigmatocystin and OTA could result in exceeding the established health-based guidance values for these toxins.  相似文献   

9.
The fluorescence micromethod of aflatoxins B1, B2, G1 and G2 determination in solution is described. The amount about 0.1 μg of aflatoxins B1 and G1, and 0,01 μg of aflatoxins B2 and G2 in one spot after elution with methanol can be determined, with accuracy about 5%. The results of described fluorescence method are in agreement with results of spectrophotometric, fluorodensitometric and visual determinations. A very strong influence of light on results of aflatoxins B1 and G1 determination was stated. Photodecomposition of aflatoxins B1 and G1 to several photoproducts was observed.  相似文献   

10.
A sensitive and reliable multi-mycotoxin method was developed for the simultaneous determination of 16 toxicological important mycotoxins, such as aflatoxins B1, B2, G1, and G2; enniatins A, A1, B, and B1; beauvericin; ochratoxin A; fumonisin B1, B2, and B3; diacetoxyscirprenol; HT-2; and T-2 toxin in dried fruits using liquid chromatography combined with electrospray ionization-triple quadrupole tandem-mass spectrometry. Mycotoxins have been extracted from the samples using a modified quick, easy, cheap, effective, rugged, and safe procedure. The method was based on a single extraction with acidified acetonitrile, followed by partitioning with salts, avoiding any further clean-up step. Limits of detections ranged from 0.08 to 15 μg kg?1 and limits of quantification ranged from 0.2 to 45 μg kg?1, which were below the legal limit set by the European Union for the legislated mycotoxines. The recoveries in spiked samples ranged from 60 to 135 % except for beauvericin using matrix-matched calibration curves for quantification, with good inter- and intraday repeatability (respective relative standard deviation ≤20 and 9 %). The developed method was applied to 15 commercial dried fruits: raisins, figs, apricots, plums, and dates purchased in local markets from Spain. Among the mycotoxins studied, enniantins and aflatoxins were the most predominant mycotoxins.  相似文献   

11.
In this study, 180 red chilli pepper (RCP) berry samples were obtained from two different croplands of Gaziantep and Kahramanmara? (Turkey) in August, September and October. RCP berry samples were dried under sunlight and grinded. Ground red chilli pepper (GRCP) samples were analysed for aflatoxins (AFs, sum of B1, B2, G1 and G2) and AFB1 contamination. According to the results, in 49 of 180 samples, AFB1 and in 37 samples, AFs were higher than legal limits. The lowest amounts of AFs and AFB1 were obtained in August and the highest amounts in October. χ2 analysis showed that there were no significant differences (p > 0.05) between cities among 3 months according to number of samples with AFs and AFB1 above legal limits. According to the Duncan multiple-range test, there was no significant difference between all months. Strict measures are necessary to produce high-quality GRCP. RCP berry must be treated to reduce moulds before production of GRCP.  相似文献   

12.
Fumonisins B1, B2 and B3 (FB1, FB2 and FB3) and aflatoxins B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) are both major mycotoxins of food concern, because of their wide range of concentration and possible co-occurrence. Therefore, a contamination survey in corn and wheat flour by liquid chromatography–tandem mass spectrometry was carried out. Quantification of fumonisins and aflatoxins was based on internal calibration (by the use of 13C34-fumonisin) and external calibration, respectively. Fumonisins were detected in 95% of corn samples and in 7% of wheat flour samples, with the mean level (FB1?+?FB2?+?FB3) of 441?µg?kg?1 and 0.09?µg?kg?1, respectively. Low levels of aflatoxins were detected in 37% of the samples with a mean level (B1?+?B2?+?G1?+?G2) of 0.12?µg?kg?1. Fumonisins and aflatoxins were not detected in 29% of the samples analysed. Simultaneous occurrence of fumonisins and aflatoxins was observed in 12% of samples.  相似文献   

13.
A total of 85 nuts and their products marketed in South Korea were assessed for aflatoxins using a monitoring scheme consisting of enzyme-linked immunosorbent assay (ELISA) for rapid screening, high performance liquid chromatography (HPLC) for quantification and LC–mass spectrometry (MS) for confirmation. Thirty-one out of 85 samples gave ELISA readings above 0.06 and were screened as possible positive samples. Aflatoxin contents of possible positive samples were determined using HPLC with a detection limit of 0.08–1.25 μg/kg and a quantification limit of 0.15–2.50 μg/kg. Nine samples including 1 raw peanut, 4 roasted peanuts, 2 peanut butters, 1 pistachio and 1 seasoned assorted nut were contaminated with aflatoxins (10.6% of incidence), ranging in various levels up to 28.2 μg/kg. LC–MS analysis on contaminated samples revealed that peaks eluting at 4.4, 5.2, 9.1 and 11.9 min were confirmed as aflatoxin G1, aflatoxin B1, aflatoxin G2 and aflatoxin B2, respectively.  相似文献   

14.
A total of 126 local and imported samples of commercial white and black pepper in Malaysia were analysed for aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2) content using high-performance liquid chromatography (HPLC) with a fluorescence detector (FD). An acetonitrile–methanol–water (17 : 29 : 54; v/v) mixture was used as a mobile phase and clean-up was using an immunoaffinity column (IAC). Seventy out of 126 (55.5%) samples were contaminated with total aflatoxins, although only low levels of aflatoxins were found ranging from 0.1 to 4.9 ng g?1. Aflatoxin B1 showed the highest incidence of contamination and was found in all contaminated samples. There was a significant difference between type of samples and different brands (p < 0.05). The results showed black peppers were more contaminated than white peppers.  相似文献   

15.
This study has examined the occurrence of aflatoxins in 168 samples of different fractions obtained during the processing of cocoa in manufacturing plants (shell, nibs, mass, butter, cake and powder) using an optimised methodology for cocoa by-products. The method validation was based on selectivity, linearity, limit of detection and recovery. The method was shown to be adequate for use in quantifying the contamination of cocoa by aflatoxins B1, B2, G1 and G2. Furthermore, the method was easier to use than other methods available in the literature. For aflatoxin extraction from cocoa samples, a methanol–water solution was used, and then immunoaffinity columns were employed for clean-up before the determination by high-performance liquid chromatography. A survey demonstrated a widespread occurrence of aflatoxins in cocoa by-products, although in general the levels of aflatoxins present in the fractions from industrial processing of cocoa were low. A maximum aflatoxin contamination of 13.3?ng?g?1 was found in a nib sample. The lowest contamination levels were found in cocoa butter. Continued monitoring of aflatoxins in cocoa by-products is nevertheless necessary because these toxins have a high toxicity to humans and cocoa is widely consumed by children through cocoa-containing products, like candies.  相似文献   

16.
BACKGROUND: Most of the maize silage stored in horizontal silos is exposed to air and can be spoiled by fungi. Potentially toxigenic fungi have been found in maize silage, and about 300 mycotoxins have been detected. Among these mycotoxins, the most harmful for feed and food safety are aflatoxins. The aim of the study was to set up a specific method to detect aflatoxins in maize silage, and to investigate whether aflatoxin contamination in maize silage depends on the level of field contamination of the crop, and whether the occurrence of aerobic spoilage during ensiling has any effect on the final contamination of the silage. RESULTS: A method for the determination of aflatoxin B1, B2, G1 and G2 in maize silage using high‐performance liquid chromagraphy with fluorescence detection has been developed and validated. Recoveries of aflatoxin B1, B2, G1, and G2 spiked over the 0.25 to 5 µg kg?1 range averaged 74–94%. The results of laboratory scale and farm scale ensiling experiments indicated that aflatoxins could increase when silage is exposed to air during conservation or during the feed‐out phase. CONCLUSIONS: The method here proposed to detect aflatoxins in silages has proved to be sensitive and is able to detect levels of 0.1 and 0.5 ng mL?1 for AFB1 and AFG1, and between 0.025 and 0.125 ng mL?1 for AFB2 and AFG2. This study also provides evidence of aflatoxin accumulation in whole crop maize silage as a result of aerobic exposure. Copyright © 2011 Society of Chemical Industry  相似文献   

17.
This paper reported on selective Raman spectroscopic and mass spectrometric determination of functionalized aflatoxins. Performance parameter methods encompassed six component mixtures of AFs, B1, G1, M1 and B2A, G2A, and M2A at concentration range of ∈ 0.096–21.581?ng g?1. Limits of detection (LODs) and limits of quantitation (LOQ) are 0.135 and 0.45 ng g?1, respectively. The matrix effect of AFB2A, AFG2A, and AFM2A in multicomponent mixtures is evaluated. The LODs of 0.11–0.09 ng g?1 is achieved. Raman spectroscopic method performance parameters at concentration range of ∈ 0.10–5,000 μg kg?1 for six component mixtures (r 2?=?0.97651) are LOD?=?10.13 μg kg?1 and LOQ?=?33.76?μg kg?1. The designed experimental schedule and sampling model is tested on contaminated grain samples. As far as the biochemistry and genetic engineering of aflatoxins and their major metabolites involved the high regioselectivity and binding affinity to N7 guanine residue at DNA, causing carcinogenic and mutagenic effects, the data reported are of emergency on the frontier fields of analytical chemistry, environmental bioengineering, monitoring, and assessment of human health risk from aflatoxins contamination. Aflatoxins are considered as biochemical weapons. Therefore, the essence of the study is on the instrumental methodology, which would be of interest and encompassed public security research and related scientific elaborations of more effective methods for (1) prevention, (2) reducing of the damages, and/or (3) acquisition of the outgrowths from biological (chemical) terrorist attacks.  相似文献   

18.
This study reports the fungal and bacterial metabolites associated with natural contamination of 38 composite samples of locally processed rice from five agro-ecological zones of Nigeria (AEZs). The samples were evaluated for the presence of microbial metabolites by LC-MS/MS. Among the identified metabolites, 63 fungal and 5 bacterial metabolites were measured at varying concentrations and occurrence levels. Fusarium toxins had the highest incidence of 79%, but occurred in low amounts with fumonisin B1 (FB1) having the highest percentage incidence of 39.5% and a mean of 18.5 µg/kg. Among the Aspergillus toxins, aflatoxins (AFs) occurred in 36.9% of the rice samples, with aflatoxin B1 (AFB1) having the highest occurrence level of 18.4% and a mean value of 5 µg/kg. About 12 metabolites had incidence levels > 50%, including beauvericin (BEA) and tryptophol, which had occurrence levels of 100%. Among the emerging toxins under evaluation by international organisations such as the European Food Safety Authority (EFSA) and the Food and Agriculture Organisation of the United Nations (FAO), citrinin, sterigmatocystin (STER) and beauvericin were detected with maximum values of 207, 125 and 131 μg/kg, respectively. This paper also reports the first documented evidence of the contamination of Nigerian rice by bacterial and Alternaria metabolites, nivalenol, kojic acid, STER, moniliformin, fusaric acid, fumonisin B3, citrinin, 3-nitropropionic acid, andrastin A, cytochalasins, emodin and physicon.  相似文献   

19.
The occurrence of aflatoxins (AF) B1, B2, G1, G2 and cyclopiazonic acid (CPA) in feeds, and AFM1 and CPA in milk was determined in dairy farms located in the northeastern region of São Paulo state, Brazil, between October 2005 and February 2006. AF and CPA determinations were performed by HPLC. AFB1 was found in 42% of feed at levels of 1.0–26.4 µg kg?1 (mean: 7.1 ± 7.2 µg kg?1). The concentrations of AFM1 in raw milk varied between 0.010 and 0.645 µg l?1 (mean: 0.104 ± 0.138 µg l?1). Only one sample was above the tolerance limit adopted in Brazil (0.50 µg l?1) for AFM1 in milk. Regarding CPA in feed, six (12%) samples showed concentrations of 12.5–153.3 µg kg?1 (mean: 57.6 ± 48.7 µg kg?1). CPA was detected in only three milk samples (6%) at levels of 6.4, 8.8 and 9.1 µg l?1. Concentrations of aflatoxins and CPA in feed and milk were relatively low, although the high frequency of both mycotoxins indicates the necessity to continuously monitor dairy farms to prevent contamination of feed ingredients.  相似文献   

20.
Rice is an important cereal but it is often contaminated with aflatoxins (AFs). The purpose of this study was to identify and quantify AF (B1, B2, G1, and G2) in 67 rice samples cultivated in Mexico and Spain, and from imported crops collected in 2008 and 2009. The methodology was validated, the rice samples were concentrated and purified with immunoaffinity columns and were quantified by high‐pressure liquid chromatography (HPLC). The average total AF (AFt) in the Spanish rice was 37.3 μg/kg, the range was from 1.6 to 1383 μg/kg, the most contaminated samples being from San Juan de Aznalfarache, Sevilla (AFt = 138.6 μg/kg), from Tortosa, Tarragona (AFt = 104.6 μg/kg), and Calasparra, Murcia (AFt = 103.9 μg/kg). The rice imported from France to Spain had AFt of 26.6 μg/kg and from Pakistan AFt of 18.4 μg/kg, showing less AF contamination than the local one. The rice which originated from Mexico contained (AFt = 16.9 μg/kg), and those imported from the United States (AFt = 14.4 μg/kg) and Uruguay (AFt = 15.6 μg/kg). The imported rice had better quality in terms of the presence of AFs.  相似文献   

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