LC–MS/MS multi-method for mycotoxins after single extraction,with validation data for peanut,pistachio, wheat,maize, cornflakes,raisins and figs

Mycotoxin analysis is usually carried out by high performance liquid chromatography after immunoaffinity column cleanup or in enzyme-linked immunosorbent assay tests. These methods normally involve determination of single compounds only. EU legislation already exists for the aflatoxins, ochratoxin A and patulin in food, and legislation will come into force for deoxynivalenol, zearalenone and the fumonisins in 2007. To enforce the various legal limits, it would be preferable to determine all mycotoxins by routine analysis in different types of matrices in one single extract. This would also be advantageous for HACCP control purposes. For this reason, a multi-method was developed with which 33 mycotoxins in various products could be analysed simultaneously. The mycotoxins were extracted with an acetonitrile/water mixture, diluted with water and then directly injected into a LC–MS/MS system. The mycotoxins were separated by reversed-phase HPLC and detected using an electrospray ionisation interface (ESI) and tandem MS, using MRM in the positive ion mode, to increase specificity for quality control. The following mycotoxins could be analysed in a single 30-min run: Aflatoxins B₁, B₂, G₁ and G₂, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, HT-2 toxin, α-zearalenol, α-zearalanol, β-zearalanol, sterigmatocystin, cyclopiazonic acid, penicillic acid, fumonisins B₁, B₂ and B₃, diacetoxyscirpenol, 3- and 15-acetyl-deoxynivalenol, zearalanone, ergotamin, ergocornin, ergocristin, α-ergocryptin, citrinin, roquefortin C, fusarenone X, nivalenol, mycophenolic acid, alternariol and alternariol monomethyl ether. The limit of quantification for the aflatoxins and ochratoxin A was 1.0 µg kg^?1 and for deoxynivalenol 50 µg kg^?1. The quantification limits for the other mycotoxins were in the range 10–200 µg kg^?1. The matrix effect and validation data are presented for between 13 and 24 mycotoxins in peanuts, pistachios, wheat, maize, cornflakes, raisins and figs. The method has been compared with the official EU method for the determination of aflatoxins in food and relevant FAPAS rounds. The multi-mycotoxin method has been proven by the detection of more than one mycotoxin in maize, buckwheat, figs and nuts. The LC–MS/MS technique has also been applied to baby food, which is subject to lower limits for aflatoxin B₁ and ochratoxin A, ergot alkaloids in naturally contaminated rye and freeze-dried silage samples.     

LC-MS/MS multi-method for mycotoxins after single extraction, with validation data for peanut, pistachio, wheat, maize, cornflakes, raisins and figs

Mycotoxin analysis is usually carried out by high performance liquid chromatography after immunoaffinity column cleanup or in enzyme-linked immunosorbent assay tests. These methods normally involve determination of single compounds only. EU legislation already exists for the aflatoxins, ochratoxin A and patulin in food, and legislation will come into force for deoxynivalenol, zearalenone and the fumonisins in 2007. To enforce the various legal limits, it would be preferable to determine all mycotoxins by routine analysis in different types of matrices in one single extract. This would also be advantageous for HACCP control purposes. For this reason, a multi-method was developed with which 33 mycotoxins in various products could be analysed simultaneously. The mycotoxins were extracted with an acetonitrile/water mixture, diluted with water and then directly injected into a LC-MS/MS system. The mycotoxins were separated by reversed-phase HPLC and detected using an electrospray ionisation interface (ESI) and tandem MS, using MRM in the positive ion mode, to increase specificity for quality control. The following mycotoxins could be analysed in a single 30-min run: Aflatoxins B1, B2, G1 and G2, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, HT-2 toxin, alpha-zearalenol, alpha-zearalanol, beta-zearalanol, sterigmatocystin, cyclopiazonic acid, penicillic acid, fumonisins B1, B2 and B3, diacetoxyscirpenol, 3- and 15-acetyl-deoxynivalenol, zearalanone, ergotamin, ergocornin, ergocristin, alpha-ergocryptin, citrinin, roquefortin C, fusarenone X, nivalenol, mycophenolic acid, alternariol and alternariol monomethyl ether. The limit of quantification for the aflatoxins and ochratoxin A was 1.0 microg kg(-1) and for deoxynivalenol 50 microg kg(-1). The quantification limits for the other mycotoxins were in the range 10-200 microg kg(-1). The matrix effect and validation data are presented for between 13 and 24 mycotoxins in peanuts, pistachios, wheat, maize, cornflakes, raisins and figs. The method has been compared with the official EU method for the determination of aflatoxins in food and relevant FAPAS rounds. The multi-mycotoxin method has been proven by the detection of more than one mycotoxin in maize, buckwheat, figs and nuts. The LC-MS/MS technique has also been applied to baby food, which is subject to lower limits for aflatoxin B1 and ochratoxin A, ergot alkaloids in naturally contaminated rye and freeze-dried silage samples.     

LC-MS/MS multi-method for mycotoxins after single extraction, with validation data for peanut, pistachio, wheat, maize, cornflakes, raisins and figs.

Mycotoxin analysis is usually carried out by high performance liquid chromatography after immunoaffinity column cleanup or in enzyme-linked immunosorbent assay tests. These methods normally involve determination of single compounds only. EU legislation already exists for the aflatoxins, ochratoxin A and patulin in food, and legislation will come into force for deoxynivalenol, zearalenone and the fumonisins in 2007. To enforce the various legal limits, it would be preferable to determine all mycotoxins by routine analysis in different types of matrices in one single extract. This would also be advantageous for HACCP control purposes. For this reason, a multi-method was developed with which 33 mycotoxins in various products could be analysed simultaneously. The mycotoxins were extracted with an acetonitrile/water mixture, diluted with water and then directly injected into a LC-MS/MS system. The mycotoxins were separated by reversed-phase HPLC and detected using an electrospray ionisation interface (ESI) and tandem MS, using MRM in the positive ion mode, to increase specificity for quality control. The following mycotoxins could be analysed in a single 30-min run: Aflatoxins B1, B2, G1 and G2, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, HT-2 toxin, alpha-zearalenol, alpha-zearalanol, beta-zearalanol, sterigmatocystin, cyclopiazonic acid, penicillic acid, fumonisins B1, B2 and B3, diacetoxyscirpenol, 3- and 15-acetyl-deoxynivalenol, zearalanone, ergotamin, ergocornin, ergocristin, alpha-ergocryptin, citrinin, roquefortin C, fusarenone X, nivalenol, mycophenolic acid, alternariol and alternariol monomethyl ether. The limit of quantification for the aflatoxins and ochratoxin A was 1.0 microg kg(-1) and for deoxynivalenol 50 microg kg(-1). The quantification limits for the other mycotoxins were in the range 10-200 microg kg(-1). The matrix effect and validation data are presented for between 13 and 24 mycotoxins in peanuts, pistachios, wheat, maize, cornflakes, raisins and figs. The method has been compared with the official EU method for the determination of aflatoxins in food and relevant FAPAS rounds. The multi-mycotoxin method has been proven by the detection of more than one mycotoxin in maize, buckwheat, figs and nuts. The LC-MS/MS technique has also been applied to baby food, which is subject to lower limits for aflatoxin B1 and ochratoxin A, ergot alkaloids in naturally contaminated rye and freeze-dried silage samples.     

Short communication: Analysis of mycotoxins in Spanish milk

We surveyed the presence of 22 mycotoxins in 191 Spanish cow milk samples. Mycotoxins could be carried over from diet into animal milk and have toxic effects on human and animal health. The interaction of different mycotoxins may be additive or synergetic. Therefore, surveillance of mycotoxin co-occurrence in milk is recommended. Aflatoxins M₁, B₁, B₂, G₁, and G₂, ochratoxins A and B, nivalenol, deoxynivalenol, deepoxy-deoxynivalenol, 3- and 15-acetyldeoxynivalenol, diacetoxyscirpenol, neosolaniol, fusarenon X, T-2 and HT-2 toxins, fumonisins B₁, B₂, and B₃, sterigmatocystin, and zearalenone were analyzed. Samples were treated by liquid-liquid extraction with acidified acetonitrile, followed by an acetonitrile-water phase separation using sodium acetate. The analysis was carried out by HPLC coupled to a triple quadrupole mass spectrometer. None of the analyzed mycotoxins had a concentration level higher than their detection limit (0.05–10.1 µg/L). The aflatoxin M₁ in the samples never exceeded the level established by the European Union.     

Relative severity of fumonisin contamination of cereal crops in West Africa

Traditional and improved varieties of maize, pearl millet and sorghum were planted by small-scale farmers under the direction of the International Institute for Tropical Agriculture in two Nigerian agro-ecological zones: the Sudan Savanna and the Northern Guinea Savanna. Samples were collected for the determination of Fusarium infection and fumonisin (B₁, B₂ and B₃) contamination. A previous paper reported Aspergillus infection and aflatoxin contamination of these samples. Fusarium infection levels, measured by per cent kernels infected, were modest with mean levels for the above cereals of 16% ± 11% (SD), 12% ± 7% and 13% ± 16%, respectively. However, the Fusarium species recovered from maize were predominantly the fumonisin producers F. verticillioides and F. proliferatum, together making an infection rate of 15% ± 10%, whereas these species were present to a limited extent only in the other two cereals, 1% ± 1% for pearl millet and 2% ± 6% for sorghum. Fumonisin contamination was variable but reflected the diversity of Fusarium producers in these three cereals. Mean levels were 228 ± 579 µg kg^–1 (range < 5–2860 µg kg^–1) for maize, 18 ± 7 µg kg^–1 (range = 6–29 µg kg^–1) for pearl millet and 131 ± 270 µg kg^–1 (range < 5–1340 µg kg^–1) for sorghum. Together with previous results on aflatoxin, this study confirmed the co-occurrence of aflatoxins and fumonisins in maize as well as in the traditional African cereals, millet and sorghum (89% co-occurrence across all three cereals). The low fumonisin levels may be ascribed to the use of good agricultural practices. Of the Fusarium species present, those in maize consisted mainly of fumonisin producers, the opposite of what was observed in pearl millet and sorghum. It is concluded that replacement of maize by pearl millet and sorghum could improve food safety with regards to aflatoxin B and fumonisin B exposure.     

Mycotoxins in corn and wheat silage in Israel

Silage is an important feed source for intensive dairy herds worldwide. Fungal growth and mycotoxin production before and during silage storage is a well-known phenomenon, resulting in reduced nutritional value and a possible risk factor for animal health. With this in mind, a survey was conducted to determine for the first time the occurrence of mycotoxins in corn and wheat silage in Israel. A total of 30 corn and wheat silage samples were collected from many sources and analysed using a multi-mycotoxin method based on LC-MS/MS. Most mycotoxins recorded in the present study have not been reported before in Israel. Overall, 23 mycotoxins were found in corn silage; while wheat silage showed a similar pattern of mycotoxin occurrence comprising 20 mycotoxins. The most common post-harvest mycotoxins produced by the Penicillium roqueforti complex were not found in any tested samples, indicative of high-quality preparation and use of silage. Moreover, none of the European Union-regulated mycotoxins – aflatoxin B1, ochratoxin, T-2 toxin, diacetoxyscirpenol and deoxynivalenol – were found above their limits of detection (LODs). The Alternaria mycotoxins – macrosporin, tentoxin and alternariol methyl ether – were highly prevalent in both corn and wheat silage (>80%), but at low concentrations. The most prominent (>80%) Fusarium mycotoxins in corn silage were fusaric acid, fumonisins, beauvericin, monilifomin, equisetin, zearalenone and enniatins, whereas in wheat silage only beauvericin, zearalenone and enniatins occurred in more than 80% of the samples. The high prevalence and concentration of fusaric acid (mean = 765 µg kg^–1) in Israeli corn silage indicates that this may be the toxin of highest potential concern to dairy cow performance. However, more data from different harvest years and seasons are needed in order to establish a more precise evaluation of the mycotoxin burden in Israeli silage.     

Presence of mycotoxins in sorghum and intake estimation in Tunisia

Sorghum samples (n = 60) from Tunisian markets were analysed for the occurrence of 22 of both traditional and emerging mycotoxins. Samples were extracted with a QuEChERS-like method and mycotoxins were detected by LC-MS/MS. This method was validated and adequate analytical parameters were obtained. All samples had contamination with mycotoxins and several samples had higher contamination levels than European Union legislative limits (MLs). The most frequently found mycotoxins were ENB (100%), OTA (98%), ENA₁ (63%), ENB₁ (56%), BEA (48%), AFB1 (38%) and STG (33%). Mean contaminations were 30.7, 1.93, 33.2, 51.0, 15.4, 1.49 and 20.5 µg kg^–1, respectively. While two samples were contaminated with FB2 and FB3 at mean values of 16.2 and 45.9 µg kg^–1, respectively, one sample was contaminated with AFB2 and ZEA at levels of 0.82 and 45.0 µg kg^–1, respectively. The results were used to estimate the daily intake of mycotoxins through sorghum consumption with regard to normal consumers (low-risk population) and high consumers such as babies (high-risk consumers) who are facing an alarming situation.     

Development of a new method for the simultaneous determination of 21 mycotoxins in coffee beverages by liquid chromatography tandem mass spectrometry

A new method for the simultaneous detection of 21 mycotoxins (ochratoxin A, aflatoxin B₁, aflatoxin B_2, aflatoxin G₁, aflatoxin G₂, sterigmatocystin, nivalenol, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, diacetoxyscirpenol, neosolaniol, HT-2 toxin, T-2 toxin, fumonisin B₁, fumonisin B₂, enniatin A, enniatin A₁, enniatin B, enniatin B₁, and beauvericin) in coffee beverages was internally validated. The method is based on liquid/liquid extraction with a mixture of ethyl acetate/formic acid (95:5 v/v) and detection using triple quadrupole (QqQ) and ion trap (IT) liquid chromatography tandem mass spectrometry. The limits of detection and quantification were 0.02 to 39.64 μg/kg, respectively, and the correlation coefficients were optimal for all mycotoxins (R² ≥ 0.992). The recovery values ranged from 72% to 97%. The developed method was demonstrated in six real samples of roasted and instant coffee, caffeinated and decaffeinated coffee, and coffee with sugar added. The analyses indicate the presence of the studied mycotoxins in coffee beverages at μg/kg concentrations. Ochratoxin A, a mycotoxin that is regulated in coffee, was detected in two samples under the maximum limit established by a European legislation (CE1881/2006).     

Utilising an LC-MS/MS-based multi-biomarker approach to assess mycotoxin exposure in the Bangkok metropolitan area and surrounding provinces

Human exposures to mycotoxins through dietary intake are a major health hazard and may result in various pathophysiological effects. Although Thailand is a country at increased risk due to its climatic conditions, no comprehensive dataset is available to perform proper exposure assessment of its population with regard to mycotoxins. Therefore, this pilot study was conducted to investigate and evaluate the exposure levels of major mycotoxins (aflatoxin B₁, ochratoxin A, fumonisins, zearalenone and trichothecenes). Sixty first-morning urine samples were collected from healthy volunteers who live in the Bangkok metropolitan area and surrounding provinces (Pathumthani, Nonthaburi, Samutprakarn and Samutsakorn). Urine samples were analysed by a LC-MS/MS-based multi-biomarker method following a so-called ‘dilute and shoot’ approach. Results generally indicated low mycotoxin exposures in most individuals through the determination of the four biomarkers that were detected in urine samples, i.e. aflatoxin M₁, ochratoxin A (OTA), as well as the deoxynivalenol (DON) metabolites DON-3-glucuronide and DON-15-glucuronide in 10 of 60 individuals. The maximum concentrations were used to estimate the daily intake confirming that none of the individuals exceeded the tolerable daily intake (TDI) of DON (maximum 26% of TDI) or OTA (maximum 22% of TDI). However, the maximum exposure of aflatoxin B₁, estimated to be 0.91 µg (kg bw)^–1 day^–1, should raise some concerns and suggests further studies utilising a more sensitive method. Low exposure to Fusarium toxins was also confirmed by the absence of zearalenone, α-zearalanol, β-zearalanol and zearalenone-14-glucuronide as well as T-2 toxin, HT-2 toxin, nivalenol and free DON. This is the first multi-mycotoxin biomarker study performed in Southeast Asia.     

Dietary exposure to mycotoxins of the Hong Kong adult population from a Total Diet Study

Dietary exposure of Hong Kong adults to mycotoxins and their metabolites including aflatoxins (AFs), ochratoxin A (OTA), fumonisins (FNs), deoxynivalenol (DON), acetyldeoxynivalenols (AcDONs) and zearalenone (ZEA) was estimated using the Total Diet Study (TDS) approach to assess the associated health risk to the local people. Sixty commonly consumed food items, collected in four seasons, were sampled and prepared as consumed. These mycotoxins were primarily found at low levels. The highest mean levels (upper bound) were: AFs, 1.50 µg kg^–1 in legumes, nuts and seed; OTA, 0.22 µg kg^–1 in sugars and confectionery; FNs, 9.76 µg kg^–1 in cereals and their products; DON and AcDONs, 33.1 µg kg^–1 in cereals and their products; and ZEA, 53.8 µg kg^–1 in fats and oils. The estimated dietary exposures of Hong Kong adults to the mycotoxins analysed were well below the respective health-based guidance values, where available. For AFs, the upper-bound exposure for high consumers is 0.0049 µg kg bw^–1 day^–1, which was estimated to contribute to about 7.7 (< 1%) of liver cancer cases when compared with 1222 liver cancer cases per year in Hong Kong. The percentage contributions of the estimated 95th percentile dietary exposures (lower and upper bound) to the health-based guidance values of individual mycotoxins were: ochratoxin A, 3.6–9.2%; fumonisins, 0.04–8.5%; deoxynivalenol and acetyldeoxynivalenols, 21.7–28.2%; and zearalenone 3.3–34.5%. The findings indicate that dietary exposures to all the mycotoxins analysed in this study were unlikely to pose an unacceptable health risk to the Hong Kong population.     

Determination of mycotoxins in biscuits,dried fruits and fruit jams: an assessment of human exposure

ABSTRACT

A reliable, fast and simple method using UHPLC-MS/MS was developed for the determination of aflatoxins B₁ (AFB1), G₁ (AFG1), B₂ (AFB2) and G₂ (AFG2), ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEA), HT-2 toxin and T-2 toxin in crude extracts of biscuits with fruit filling, cookies, dried fruits and fruit jams. The method was successfully demonstrated on 39 samples of biscuits with fruit filling, 34 cookies, 14 dried fruits and 10 fruit jams. The mycotoxins detected in biscuits samples were ZEA, OTA, T-2 and AFB1 with an average concentrations of positive samples of 2.64, 4.10, 8.13 and 1.32 µg kg^?1, respectively; while the mycotoxins detected in jam samples were AFB1, OTA, T-2 and AFB2 with an average concentrations of positive samples of 2.00, 17.7, 4.37 and 1.15 µg kg^?1, respectively. The results showed that the majority of samples were in compliance with relevant regulations. However in eight samples of biscuits and three samples of fig jam the contents of OTA were higher than the existing OTA limits. The combined dietary exposure of selected mycotoxins was estimated for the first time for children, adolescents and adults. The estimated combined dietary exposures were all lower than the proposed value assumed to predict a possible risk scenario.     

Effectiveness of hand sorting,flotation/washing,dehulling and combinations thereof on the decontamination of mycotoxin-contaminated white maize

Maize is one of the major staple foods of Sub-Saharan Africa and is consumed as whole or dehulled grain. In this region, where the environmental conditions favour fungal growth and mycotoxin production, the majority of the population are subsistence consumers who, unfortunately, have little or no access to mycotoxin testing of their food. In an attempt to develop feasible reduction strategies in dietary mycotoxin exposure of the population, a three-factorial design experiment was conducted to examine and compare the efficacy of hand sorting, flotation, dehulling and combinations thereof in removing naturally occurring aflatoxins, fumonisins, nivalenol, deoxynivalenol and alternariol in shelled white maize. Regression analysis was used to determine the significant (p < 0.05) process variables on the removal of mycotoxins from the maize. Results from this experiment indicated that hand sorting had the greatest effect on mycotoxin removal, while flotation yielded the least effect. In particular hand sorting left < 6% of aflatoxin B1 and < 5% of fumonisin B1. Based on these results, hand sorting of maize grains is being recommended as a last line of defence against mycotoxin exposure among subsistence consumers.     

Mycotoxin Biomarkers of Exposure: A Comprehensive Review

To date, the use of biomarkers has become generally accepted. Biomarker‐driven research has been proposed as a successful method to assess the exposure to xenobiotics by using concentrations of the parent compounds and/or metabolites in biological matrices such as urine or blood. However, the identification and validation of biomarkers of exposure remain a challenge. Recent advances in high‐resolution mass spectrometry along with new analytical (post‐acquisition data‐mining) techniques will improve the quality and output of the biomarker identification process. Chronic or even acute exposure to mycotoxins remains a daily fact, and therefore it is crucial that the mycotoxins’ metabolism is unravelled so more knowledge on biomarkers in humans and animals is acquired. This review aims to provide the scientific community with a comprehensive overview of reported in vitro and in vivo mycotoxin metabolism studies in relation to biomarkers of exposure for deoxynivalenol, nivalenol, fusarenon‐X, T‐2 toxin, diacetoxyscirpenol, ochratoxin A, citrinin, fumonisins, zearalenone, aflatoxins, and sterigmatocystin.     

LC-MS/MS multi-analyte method for mycotoxin determination in food supplements

A multi-analyte method for the liquid chromatography-tandem mass spectrometric determination of mycotoxins in food supplements is presented. The analytes included A and B trichothecenes (nivalenol, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, neosolaniol, fusarenon-X, diacetoxyscirpenol, HT-2 toxin and T-2 toxin), aflatoxins (aflatoxin-B₁, aflatoxin-B₂, aflatoxin-G₁ and aflatoxin-G₂), Alternaria toxins (alternariol, alternariol methyl ether and altenuene), fumonisins (fumonisin-B₁, fumonisin-B₂ and fumonisin-B₃), ochratoxin A, zearalenone, beauvericin and sterigmatocystin. Optimization of the simultaneous extraction of these toxins and the sample pretreatment procedure, as well as method validation were performed on maca (Lepidium meyenii) food supplements. The results indicated that the solvent mixture ethyl acetate/formic acid (95:5, v/v) was the best compromise for the extraction of the analytes from food supplements. Liquid–liquid partition with n-hexane was applied as partial clean-up step to remove excess of co-extracted non-polar components. Further clean-up was performed on Oasis HLB? cartridges. Samples were analysed using an Acquity UPLC system coupled to a Micromass Quattro Micro triple quadrupole mass spectrometer equipped with an electrospray interface operated in the positive-ion mode. Limits of detection and quantification were in the range of 0.3–30 ng g^?1 and 1–100 ng g^?1, respectively. Recovery yields were above 60% for most of the analytes, except for nivalenol, sterigmatocystine and the fumonisins. The method showed good precision and trueness. Analysis of different food supplements such as soy (Glycine max) isoflavones, St John's wort ( Hypericum perforatum), garlic (Allium sativum), Ginkgo biloba, and black radish (Raphanus niger) demonstrated the general applicability of the method. Due to different matrix effects observed in different food supplement samples, the standard addition approach was applied to perform correct quantitative analysis. In 56 out of 62 samples analysed, none of the 23 mycotoxins investigated was detected. Positive samples contained at least one of the toxins fumonisin-B₁, fumonisin-B₂, fumonisin-B₃ and ochratoxin A.     

Occurrence and dietary exposure assessment of multiple mycotoxins in corn-based food products from Shandong,China

This study was designed to investigate the occurrence and exposure assessment of multiple mycotoxins in corn-based food products from Shandong Province, China. Results demonstrated that the mean level of total mycotoxins in test samples was 197.2 µg/kg. The most frequently found mycotoxins were deoxynivalenol (96.7%) and fumonisin B₁ (94.4%), with mean contamination levels of 65.24 and 128.2, respectively. Among these corn-based food products, thin corn pancake had the highest mean contamination (886.7 µg/kg), followed by wotou (143.7 µg/kg), corn cake (135.4 µg/kg) and mantou (63.73 µg/kg). The average exposure values to total fumonisins and deoxynivalenol were 0.05 and 0.02 µg/kg bw/day, which were lower than the provisional maximum tolerable daily intake values of 2 and 1 µg/kg bw/day, respectively, as established by the Joint FAO/WHO Expert Committee on Food Additives. In the future strict control and systematic monitoring are needed to secure food safety and human health.     

Natural co-occurrence of ochratoxin A,ochratoxin B and aflatoxins in Sicilian red wines

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 samples, while the other aflatoxins were rarely present. Recovery experiments were carried out on eight mycotoxin-free red wines spiked with OTA, OTB, AFB₁, AFB₂, AFG₁ and AFG₂ at two different levels. The limits of detection (LODs) in wines were 0.02 µg l^–1 for OTA, 0.04 µg l^–1 for OTB, 0.03 µg l^–1 for AFG₁, AFG₂ and AFB₂, and 0.05 µg l^–1 for AFB₁. A good correlation was found, with good performances in term of precision for the method.     

进口玉米酒糟粕中15种真菌毒素的检测和风险分析

建立了液相串联质谱检测玉米酒糟粕中15种真菌毒素的检测方法,并对结果分布进行了讨论。检测的真菌毒素包括黄曲霉毒素B1等15种真菌毒素。这些毒素采用溶剂提取,多功能净化柱净化,液相串联质谱检测。方法均经过优化和验证,满足进口玉米酒糟粕的检测要求。对67个进口玉米酒糟粕样品的检测结果表明,玉米赤霉烯酮、脱氧雪腐镰刀菌烯醇、T-2毒素、HT-2毒素等真菌毒素均有检出。本试验对这些数据进行了统计分析,提出了对进口玉米酒糟粕的真菌毒素风险分析结果。     

Simultaneous detection of 12 mycotoxins in cereals using RP-HPLC-PDA-FLD with PHRED and a post-column derivatization system

A new method for the simultaneous quantification of 12 mycotoxins was developed and optimized using reverse phase high performance liquid chromatography (RP-HPLC) with a photodiode array (PDA) and fluorescence detector (FLD), a photochemical reactor for enhanced detection (PHRED) and post-column derivatization. The mycotoxins included aflatoxins (AFB(1), AFB(2), AFG(1), and AFG(2)), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisins (FB(1), FB(2), and FB(3)), T-2 and HT-2 toxins. A double sample extraction with a phosphate-buffered saline solution (PBS) and methanol was used for co-extraction of mycotoxins, and a multifunctional immunoaffinity column was used for cleanup. Optimum conditions for separation of the mycotoxins were obtained to separate 12 mycotoxins in FLD and PDA chromatograms with a high resolution. The method gave recoveries in the range 72-111% when applied to spiked corn samples. The limits of detection (LOD) were 0.025 ng/g for AFB(1) and AFG(1), 0.012 ng/g for AFB(2) and AFG(2), 0.2 ng/g for OTA, 1.5 ng/g for ZEA, 6.2 ng/g for FB(1), FB(3) and HT-2 toxin, 9.4 ng/g for FB(2) and T-2 toxin, and 18.7 ng/g for DON. In addition, the limits of quantification (LOQ) ranged from 0.04 ng/g for AFB(2) and AFG(2) to 62 ng/g for DON. The method was successfully applied to the determination of these mycotoxins in 45 cereal samples obtained from the Malaysian market. The results indicated that the method can be applied for the multi-mycotoxin determination of cereals.     

The Microbial Contamination,Toxicity and Quality of Turned and Unturned Outdoor Floor Malted Sorghum

Turned and unturned outdoor floor malted sorghum were studied for their total microbial contamination, nature and extent of contamination by moulds, cytotoxicity (IC₅₀) and quality in terms of diastatic power (DP). The presence of aflatoxins, fumonisins, deoxynivalenol and zearalenone were also investigated. Total microbial counts were high (10⁷–10⁸ cfu/g) in both turned and unturned samples. All samples showed contamination by different moulds, with the dominant being Mucor species, Rhizopus oryzae, Fusarium moniliforme and Phoma sorghina as well as Aspergillus flavus and Alternaria alternata. The latter four are known for producing mycotoxins. Malt samples had very low cytotoxicity (IC₅₀ from 62.5 to >1000 kg/kg), though all contained fumonisins, deoxynivalenol and zearalenone at levels of <0.25–2 μg/g, 15–20 and 10–15 μg/kg, respectively. Malt DP was generally lower in turned samples compared to unturned samples probably because the heat conserved in the latter ensured better germination conditions. Overall, turning during germination did not affect the microbial load, mould population and levels of deoxynivalenol and zearalenone in sorghum malt but decreased sorghum malt DP. Thus, alternative methods of controlling the sorghum malt microbial load should be sought.     

The effect of chemical treatment on reduction of aflatoxins and ochratoxin A in black and white pepper during washing

The effect of 18 different chemicals, which included acidic compounds (sulfuric acid, chloridric acid, phosphoric acid, benzoic acid, citric acid, acetic acid), alkaline compounds (ammonia, sodium bicarbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide), salts (acetate ammonium, sodium bisulfite, sodium hydrosulfite, sodium chloride, sodium sulfate) and oxidising agents (hydrogen peroxide, sodium hypochlorite), on the reduction of aflatoxins B₁, B₂, G₁ and G₂ and ochratoxin A (OTA) was investigated in black and white pepper. OTA and aflatoxins were determined using HPLC after immunoaffinity column clean-up. Almost all of the applied chemicals showed a significant degree of reduction on mycotoxins (p?<?0.05). The lowest and highest reduction of aflatoxin B₁, which is the most dangerous aflatoxin, was 20.5%?±?2.7% using benzoic acid and 54.5%?±?2.7% using sodium hydroxide. There was no significant difference between black and white peppers (p?<?0.05).