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22.
Andrea Tarazona Jos Vicente Gmez Fernando Mateo Misericordia Jimnez Eva María Mateo 《Toxins》2021,13(6)
Spain is a relevant producer of oats (Avena sativa), but to date there has been no study on the occurrence/co-occurrence of mycotoxins in oats marketed in Spain. The present study is addressed to overcome this lack of knowledge. One hundred oat kernel samples were acquired across different Spanish geographic regions during the years 2015–2019 and analyzed for mycotoxin content using an ultra-high performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC–ESI–MS/MS) method and matrix-matched calibration. The focus was on the regulated mycotoxins although other relevant mycotoxins were considered. The percentage of incidence (levels ≥ limit of detection), mean and range (ng/g) of mycotoxins were as follows: zearalenone (66%, mean 39.1, range 28.1–153), HT-2 toxin (47%, mean 37.1, range 4.98–439), deoxynivalenol, (34%, mean 81.4, range 19.1–736), fumonisin B1 (29%, mean 157.5, range 63.2–217.4), and T-2 toxin, (24%, mean 49.9, range 12.3–321). Fumonisin B2, 3-acetyldeoxynivalenol, aflatoxins B1, B2, and G2, and ochratoxin A were also detected at low levels, but aflatoxin G1 was not. The maximum limits established by the European Commission for unprocessed oats were not exceeded, except for zearalenone (in one sample), and the sum of aflatoxins (in two samples). Mycotoxin co-occurrence at quantifiable levels in the same sample (two to five combinations) was found in 31% of samples. The most common mixtures were those of HT-2 + T-2 toxins alone or together with deoxynivalenol and/or zearalenone. 相似文献
23.
免疫亲和柱净化HPLC柱后光化学衍生化法检测中药及染菌中药制剂中间体的黄曲霉毒素 总被引:1,自引:1,他引:0
目的:采用免疫亲和柱净化,结合柱后光化学衍生化的高效液相色谱-荧光检测器建立同步检测常用中药材及染菌中药制剂中间体中的黄曲霉毒素B1,B2,G1,G2的方法.方法:采用免疫亲和柱净化洗脱结合柱后光化学衍生手段,建立黄曲霉毒素B1,B2,G1,G2的分析方法,并分别对14种中药材及染菌中药制剂中间体进行检测.结果:黄曲霉毒素B2和G2,B1和G1分别在0.15 ~ 6.0和0.5 ~20.0 ng·mL-1线性关系良好,方法准确稳定.所选的14种中药中川芎和柏子仁检测出黄曲霉毒素B1,而以染菌中药川芎所制备的5种提取物中均未检出黄曲霉毒素.结论:采用此方法检测常用中药材及其制剂中间体中的黄曲霉毒素无干扰性杂峰,结果准确可靠. 相似文献
24.
Mycotoxins are unavoidable contaminants produced by fungi in food, especially grains. This study aimed to measure the occurrence and levels of total aflatoxins (AFs); ochratoxin A (OTA); zearalenone (ZEN); fumonisins B1, B2, and B3 (FUM); deoxynivalenol (DON); and T-2/HT-2 toxins in the four most commonly consumed breakfast cereals in Chile and to assess mycotoxin exposure and risk in children aged 2 to 13 years due to cereal consumption. In this study, a total of 110 batches with three subsamples of the four brands were sampled in supermarkets from November 2019 to June 2021. Samples were analyzed by Veratox® ELISA (Neogen). Exposure was assessed by estimated daily intake (EDI) considering the levels found in a modified lower bound (mLB) and upper bound (UB). Risk was estimated by margin of exposure (MOE) in the case of OTA and AFs and hazard quotient (HQ) for the rest of the mycotoxins. No T2/HT2 toxins were detected. Few samples had quantifiable levels of ZEN, FUM, and DON except for brand 1, with a mean (standard deviation, SD) of 54 (20), 1552 (351), and 706 (218) ng/g, respectively. In addition, three FUM samples and one DON sample had values over the Chilean regulation. Brands 2, 3, and 4 had quantifiable levels of AFs, with mean (SD) values of 1.3 (0.1), 2.1 (0.6), and 1.9 (0.4) ng/g, respectively. Brand 3 had quantifiable levels of OTA, with a mean (SD) of 2.3 (0.4) ng/g. Estimated exposure indicated a risk of AFs in all scenarios, and of FUM for brand 1 consumption, OTA and DON for brand 3 consumption, and OTA for brand 4 consumption in the mLB worst-case scenario. In general, mycotoxin levels were below the Chilean regulatory limits, but most of them were above the EU regulation for processed cereal-based food in young children. Because the risk was higher in the 2- to 5-year-old children, we recommend special regulations for this group in Chile. 相似文献
25.
《山东中医杂志》2019,(11):1067-1071
目的:对21种中药饮片中的黄曲霉毒素B1、B2、G1、G2进行含量测定,了解中药饮片的质量状况。方法:采用高效液相色谱(HPLC)-柱后碘衍生法进行含量测定,Waters Sunfire C18色谱柱(4.6 mm×250 mm,5μm),柱温35℃,以甲醇-乙腈-水(33∶12∶55)为流动相,流速1.0 mL/min。荧光检测器激发波长λex=360 nm,发射波长λem=450 nm。以0.05%碘溶液为衍生溶液,衍生化泵流速为0.3 mL/min,衍生化温度为70℃。结果:21种中药饮片中,只有胖大海、酸枣仁、大枣、全蝎、淡豆豉、牛蒡子、千金子7个品种未检出黄曲霉毒素;4批柏子仁、6批薏苡仁全部检出黄曲霉毒素,检出率均为100%,其中3批柏子仁的黄曲霉毒素含量超出法定标准限量,不合格率75%;2批薏苡仁的黄曲霉毒素含量超出法定标准限量,不合格率33%。桃仁、陈皮等其余12个品种亦检出黄曲霉毒素,但含量未超出法定标准限度。结论:虽然黄曲霉毒素检测成本较高,但为保证用药安全、减少用药风险,对中药饮片进行合理的黄曲霉毒素监督检测具有必要性。 相似文献
26.
Muhammad Kashif Saleemi Muhammad Zargham Khan Ahrar Khan Muhammad Raza Hameed Aisha Khatoon Zain ul Abadin 《Toxin reviews》2017,36(1):80-88
The present study was designed to investigate the fungi and their toxigenic potentials isolated from the wheat and wheat brans. A total of 67 samples of wheat and 17 samples of wheat bran were collected from Faisalabad district of Pakistan. Forty-five (67.16%) samples of wheat yielded fungi. Frequency distribution based on total samples, Aspergillus was the highest (44.77%) genus followed by Penicillium, Fusarium and Alternaria. Penicillium verucosum (30.64%) was the most frequently isolated species followed by A. niger aggregates, A. flavus, A. parasiticus, P. chrysogenum, A. ochraceous, A. carbonarius and A. fumigatus. Among Aspergilli, A. niger aggregates (46.67%) were most frequently isolated species. Out of 30 Aspergilli isolates from wheat samples, 17 (56.66%) were found toxigenic. AFB1 produced by aflatoxigenic Aspergilli varied from 1.44 to 836.3?ng/g, while ochratoxin A levels varied from 0.037 to 15 045?ng/g. Among Penicillium species, P. verrucosum (63.15%) were found ochratoxigenic and OTA levels were varied from 7.31 to 8400?ng/g. In wheat bran, 10 (58.82%) samples yielded fungi. Based upon total samples, frequency distribution of Aspergillus (35.28%) was the highest followed by Penicillium and Fusarium. Similar pattern was observed in relative density of isolates. A. niger aggregates and P. verrucosum were predominant species (23.07%) isolated from wheat bran. Among Aspergilli, A. niger aggregates (50%) were the most frequently isolated species followed by A. flavus, A. fumigatus and A. ochraceous (16.67%) each. The OTA levels of fungi isolated from wheat bran varies from 0.292 to 2500?ng/g. Isolation of toxigenic A. niger aggregates from wheat indicates that these species should be considered as possible contributors of OTA contamination in wheat and its by-products in Pakistan. 相似文献
27.
Our climate is projected to change gradually over time. Mycotoxin occurrence in cereal grains is both directly and indirectly related to local weather and to climate changes. Direct routes are via the effects of precipitation, relative humidity, and temperatures on both fungal infection of the grain and mycotoxin formation. Indirect routes are via the effects of the wind dispersal of spores, insect attacks, and shifts in cereal grain phenology. This review aimed to investigate available modeling studies for climate change impacts on mycotoxins in cereal grains, and to identify how they can be used to safeguard food safety with future climate change. Using a systematic review approach, in total, 53 relevant papers from the period of 2005–2020 were retrieved. Only six of them focused on quantitative modeling of climate change impacts on mycotoxins, all in pre-harvest cereal grains. Although regional differences exist, the model results generally show an increase in mycotoxins in a changing climate. The models do not give an indication on how to adapt to climate change impacts. If available models were linked with land use and crop models, scenario analyses could be used for analyzing adaptation strategies to avoid high mycotoxin presence in cereal grains and to safeguard the safety of our feed and food. 相似文献
28.
Aflatoxin levels in chronic hepatitis B patients with cirrhosis or hepatocellular carcinoma in Balıkesir,Turkey
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Aflatoxins, the secondary metabolites produced by species of naturally occurring Aspergilli, are commonly found in food such as cereals, dried fruits and juice, wine, beer and spices. They are hepatotoxic and are well known human carcinogens based on evidence from human studies. Aflatoxins are an environmental risk factor for the development of hepatocellular carcinoma (HCC). Chronic hepatitis B‐infected patients are at increased risk of cirrhosis, hepatic failure and liver cancer. This study was designed to determine the serum aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2) concentrations using high‐pressure liquid chromatography (HPLC) in hepatitis B‐infected patients with or without cirrhosis and liver cancer, alongside healthy controls in Bal?kesir, Turkey. The mean AFB1 and total AF levels in patients without liver cancer and cirrhosis were significantly higher than healthy controls. The mean AFB1 and total AF levels in patients with chronic hepatitis B and HCC were significantly higher than infected patients with or without cirrhosis. These results suggest that patients with chronic hepatitis B who are exposed to AFs are at increased risk for developing HCC, which might be prevented by reducing consumption of contaminated foods. 相似文献
29.
The multi-mycotoxin occurrence for internal and superficial fungi contamination were comprehensively assessed in medicinal seeds used as food or beverage. Based on a polyphasic approach using morphological characters, β-tubulin and ITS gene blast, a total of 27 species belonging to 12 genera were identified from surface-sterilized seeds. Chaetomium globosporum was most predominant (23%), followed by Microascus trigonosporus (12%) and Alternaria alternata (9%). With respect to superficial mycobiota, thirty-four species belonging to 17 genera were detected. Aspergillus niger and Penicillium polonicum were predominant (12% and 15%, respectively). Medicinal seed samples and potential toxigenic fungi were tested for ochratoxin A (OTA) and aflatoxins (AFB1, AFB2, AFG1, AFG2) using UPLC-MS/MS. Platycladi seeds were contaminated with AFB1 (52.0 µg/kg) and tangerine seed was contaminated with OTA (92.3 µg/kg). Subsequent analysis indicated that one A. flavus strain isolated from platycladi seed was able to synthesize AFB1 (102.0 µg/kg) and AFB2 (15.3 µg/kg). Two P. polonicum strains isolated from tangerine and lychee seeds were able to synthesize OTA (4.1 µg/kg and 14.8 µg/kg, respectively). These results identify potential sources of OTA and aflatoxins in medicinal seeds and allude to the need to establish permitted limits for these mycotoxins in these seeds that are commonly consumed by humans. 相似文献
30.
Muhammad Asif Asghar Aftab Ahmed Javed Iqbal Erum Zahir Hina Nauman 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2016,24(3):635
This study aimed to isolate fungal pathogens and to subsequently quantify aflatoxin (AF; B1 + B2 + G1 + G2) contamination in wheat crops grown in Pakistan. Accordingly, a total of 185 wheat samples were collected from different areas of Pakistan and numerous potent fungal pathogens were isolated. AF contamination attributed to the presence of intoxicating fungal pathogens and resulting metabolic activities were quantified using a high performance liquid chromatography-fluorescence detector coupled with postcolumn derivatization. Additionally, the effect of fungal pathogens on seed germination was also examined. The results obtained showed that 50% of tested wheat samples were found to be contaminated with a diverse range of fungal species. The rate of recurrence of fungal pathogens were Aspergillus 31%, Penicillium 9%, Fusarium 8%, Rhizopus 3%, and Alternaria 2%. The presence of Tilletia indica and Claviceps purpurea species was found to be inevident in all tested wheat samples. AFB1 contamination was detected in 48 (26.0%) samples and AFB2 in 13 (7.0%) samples. AFG1 and AFG2 were not found in any of the tested samples. The contamination range of AFB1 and AFB2 was 0.05–4.78 μg/kg and 0.02–0.48 μg/kg, respectively. The total amount of AFs (B1 + B2) found in 48 (26.0%) samples had a mean level of 0.53 ± 0.40 μg/kg and a contamination range of 0.02–5.26 μg/kg. The overall results showed that in 137 (74.0%) samples, AFs were not found within detectable limits. Furthermore, in 180 (97.2%) samples, AF levels were found to be below the maximum tolerated levels (MTL) recommended by the European Union (4 μg/kg). In five (2.7%) samples, AF contamination was higher than the MTL of the European Union. However, these samples were fit for human consumption with reference to the MTL (20 μg/kg) assigned by the USA (Food and Drug Administration and Food and Agriculture Organization) and Pakistan (Pakistan Standards and Quality Control Authority). Germination rates in healthy and contaminated wheat kernels were 84.6% and 45.2%, respectively. Based on the obtained results, it was concluded that the levels of fungal pathogen and AF contamination in Pakistani-grown wheat are not a potential threat to consumer health. However, control procedures along with a strict monitoring policy are mandatory to further minimize the prevalence of fungal carriers and the potency of AFs in crops cultivated in Pakistan. 相似文献