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为了研究麦粒中脱氧雪腐镰刀菌烯醇(DON)及其隐蔽型脱氧雪腐镰刀菌烯醇-3-葡萄糖苷(D3G)的累积情况,将禾谷镰刀菌菌株F-1和5035分别人工接种至经高温灭菌、8 k Gy和15 k Gy辐照的麦粒中25℃培养7、14、21、28、35 d后,通过LC-MS/MS方法测定DON和D3G毒素在麦粒中的含量。不同处理的麦粒中DON含量均随培养时间延长逐渐增加;禾谷镰刀菌接种灭菌麦粒及15 k Gy辐照麦粒均未检出D3G毒素;禾谷镰刀菌接种8 k Gy辐照小麦籽粒后检测到隐蔽型毒素D3G,培养7 d时D3G最高且其含量随着培养时间延长逐渐降低;本文使用指数模型拟合25℃下F-1与5035接种麦粒(8 k Gy辐照)中D3G/DON的比值与时间关系的R2分别为0.97、0.93,R2均在0.9以上,说明指数模型能够较好地拟合本实验条件下时间与D3G/DON的比值的变化,为进一步后续研究提供依据。 相似文献
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目的测定不同症状的小麦赤霉病粒中脱氧雪腐镰刀菌烯醇(DON)的含量。方法采用免疫亲和层析净化高效液相色谱法测定健康、皱缩、皱缩发黑和皱缩发红的小麦籽粒中脱氧雪腐镰刀菌烯醇含量。结果健康麦粒中DON的含量为未检出,皱缩红色和皱缩发黑的麦粒中DON的含量均接近我国食品安全国家标准规定的食品中真菌毒素限量1000μg/kg;皱缩麦粒中DON的含量约为皱缩红色麦粒中的一半,极显著低于皱缩红色和皱缩发黑的麦粒(P0.01)。结论本方法能为粮食收购时判断DON毒素的含量提供理论依据。 相似文献
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Helga Tima Adrienn Berkics Zoltán Hannig András Ittzés Eleonóra Kecskésné Nagy Csilla Mohácsi-Farkas 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(1):37-42
Among Fusarium mycotoxins, deoxynivalenol (DON) is the most common contaminant in case of cereals and cereal-based foods in Hungary. In this study, Hungarian wheat (n = 305), maize (n = 108), wheat flour (n = 179) and pasta (n = 226) samples were analysed (N = 818). The samples were collected during 2008–2015 in Hungary. Applied methods of analysis were enzyme-linked immunosorbent assay and liquid-chromatography coupled with a mass spectrometer. Results were compared and evaluated with Hungarian weather data. Among cereal samples, in 2011, wheat was contaminated with DON (overall average ± standard deviation was 2159 ± 2818 µg kg?1), which was above the maximum limit (ML). In case of wheat flour and pasta, no average values above ML were found during 2008–2015, but higher DON contamination could be observed in 2011 as well (wheat flour: 537 ± 573 µg kg?1; pasta: 511 ± 175 µg kg?1). 相似文献
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Organic nitrogen transformations in a 4-stage Bardenpho nitrogen removal plant and bioavailability/biodegradability of effluent DON 总被引:2,自引:0,他引:2
Chakkrid Sattayatewa Krishna Pagilla Paul Pitt Kevin Selock Theresa Bruton 《Water research》2009,43(18):4507-4516
Nitrogen species, specifically, the fate and occurrence of organic nitrogen (ON) within a 4-stage Bardenpho process bioreactor producing low total nitrogen (TN) effluents were investigated in this study. The results showed release of ON in primary anoxic zone and no ON release in the first aerobic zone of the process. The research included investigation of biodegradability/bioavailability of wastewater-derived effluent dissolved ON (DON). The final-effluent DON utilization was evaluated by two different bioassay protocols in the presence and absence of nitrate. About 28–57% of the effluent DON was bioavailable/biodegradable. Bioavailable (to algae and bacteria) DON (ABDON) and biodegradable (to bacteria) DON (BDON) results did not show significant differences in terms of quantity, but DON utilization rates by ABDON (0.13 day−1) protocol were higher than that of the BDON (0.04 day−1) protocol in the nitrate-removal samples. As a result, ABDON requires a shorter time to exert the bioavailable fraction due to symbiotic relationship between algae and bacteria. In the nitrate-containing samples, it appears that nitrate competes with labile DON as a nitrogen source to microorganisms in both ABDON and BDON protocols. The first order decay rate of DON in the presence of nitrate was 0.11 day−1 and 0.02 day−1 for ABDON and BDON, respectively. 相似文献
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Composition of a protein-like fluorophore of dissolved organic matter in coastal wetland and estuarine ecosystems 总被引:9,自引:0,他引:9
This study demonstrates the compositional heterogeneity of a protein-like fluorescence emission signal (T-peak; excitation/emission maximum at 280/325 nm) of dissolved organic matter (DOM) samples collected from subtropical river and estuarine environments. Natural water samples were collected from the Florida Coastal Everglades ecosystem. The samples were ultrafiltered and excitation-emission fluorescence matrices were obtained. The T-peak intensity correlated positively with N concentration of the ultrafiltered DOM solution (UDON), although, the low correlation coefficient (r(2)=0.140, p<0.05) suggested the coexistence of proteins with other classes of compounds in the T-peak. As such, the T-peak was unbundled on size exclusion chromatography. The elution curves showed that the T-peak was composed of two compounds with distinct molecular weights (MW) with nominal MWs of about >5 x 10(4) (T(1)) and approximately 7.6 x 10(3) (T(2)) and with varying relative abundance among samples. The T(1)-peak intensity correlated strongly with [UDON] (r(2)=0.516, p<0.001), while T(2)-peak did not, which suggested that the T-peak is composed of a mixture of compounds with different chemical structures and ecological roles, namely proteinaceous materials and presumably phenolic moieties in humic-like substances. Natural source of the latter may include polyphenols leached from senescent plant materials, which are important precursors of humic substances. This idea is supported by the fact that polyphenols, such as gallic acid, an important constituent of hydrolysable tannins, and condensed tannins extracted from red mangrove (Rhizophora mangle) leaves exhibited the fluorescence peak in the close vicinity of the T-peak (260/346 and 275/313 nm, respectively). Based on this study the application of the T-peak as a proxy for [DON] in natural waters may have limitations in coastal zones with significant terrestrial DOM input. 相似文献
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呕吐毒素是广泛存在于粮食中的一种真菌毒素,其化学性质稳定,耐高温,对人类和动物的健康有比较严重的危害性。粮食中呕吐毒素的物理消减方法主要包括谷物加工法、吸附剂吸附法、射线辐照法和热处理法等方法。与化学脱毒法相比,物理脱毒法的成本低,处理过程中不会产生新的化学物质,且有助于减少粮食和饲料中现有的呕吐毒素。该文分析了粮食中呕吐毒素产生的原因、危害和污染现状,总结了粮食中呕吐毒素物理消减方法的研究进展,分析了各种消减方法的优缺点,并提出未来物理消减方法的研究方向和发展趋势,为进一步开发自动化、规模化、简便化和低成本高效率的物理消减方法提供参考。 相似文献
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G. Ríos N. Zakhia-Rozis M. Chaurand F. Richard-Forget M.F. Samson J. Abecassis 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(4):487-495
The milling behaviour of two naturally infected samples of durum wheat grain with contrasting levels of mycotoxins was studied. Although the two samples showed a similar milling behaviour, an increase of ~20% in deoxynivalenol (DON) levels was found in semolina from the sample containing the higher level of mycotoxin. However, even if the highest concentration of DON was found in fractions originating from the grain outer layers, the mycotoxin contamination in semolina and flours were not related to the amount of two compounds (ash or phytic acid) used to monitor these external tissues. The presence of the trichothecene-producing fungi in the inner-most semolina fraction was also shown using specific DNA primers and PCR amplification. Comparison of DON concentrations in the feed stock and corresponding output at each milling step or grinding of semolina fractions followed by sizing showed that concentration of mycotoxin occurs in the finest particles at the first processing steps. Therefore, DON contamination of milling fractions is not simply due to the presence of peripheral grain tissues. 相似文献
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BackgroundMany studies around the world reported the occurrence of many mycotoxins and their metabolites in human breast milk. However the contamination by aflatoxin M1 and ochratoxin A were the most investigated by several countries.Scope and approachTo scrutinize all papers reporting quantitative data on the prevalence and the levels of mycotoxins and their metabolites in breast milk, also the circumstances of exposure.A systematic literature search in Pubmed, Science direct and Google scholar databases were performed to identify relevant studies, published in English from 1984 through May 2015.Key findings and conclusion63 studies met the inclusion criteria and assessed the occurrence of 29 mycotoxins & their metabolites in breast milk, regarding 7194 subjects of 31 countries. The maternal dietary habits, the socio demographic status of the mother, the seasonal variations and the sensitivity of the analytical method were the factors related to the high concentrations of AFM1 and OTA in breast milk.Studies where contamination exceeds maximum limits and exhibit real risk of public health were highlighted. 相似文献