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1.
To investigate possible co-occurrences of type B trichothecenes and zearalenone within a Fusarium culmorum-infected wheat harvest lot, kernels were fractionated into six groups by visual criteria. The Fusarium-damaged kernels were subdivided into white, shrunken, and red kernel groups, and the remaining kernels were sorted into healthy, black spotted, and nonspecific groups. The distribution patterns of nivalenol, deoxynivalenol, zearalenone, and ergosterol were determined for possible correlations. Significant correlations between the distribution patterns were found for the mycotoxins and ergosterol for the grouped kernels (r = 0.997-0.999, p < 0.0001). Additionally, remarkably outstanding levels of nivalenol (24-fold more than the mean at 1.16 mg/kg), deoxynivalenol (27-fold more than the mean at 0.16 mg/kg), zearalenone (25-fold more than the mean at 77 microg/kg), and ergosterol (17-fold more than the mean at 13.4 mg/kg) were found in the red kernel group. Further, detailed mycotoxin and ergosterol analyses were carried out on various segments (kernel surface, conidia, bran, and flour) of the red kernels. However, the mycotoxin and ergosterol distribution profiles revealed nonsignificant correlations for these kernel segments, with the exception of deoxynivalenol and nivalenol, which were moderately correlated (r = 0.948, p = 0.035).  相似文献   

2.
A method is described using gas chromatography-mass spectrometry (GC-MS) for the simultaneous detection of the Fusarium mycotoxins fusaproliferin and seven trichothecenes from grains. Sample purification of the raw extract was carried out with commercial solid phase extraction columns, and the recovery of the more polar analytes was increased by rinsing the column with acetonitrile. A significant matrix effect was found for the analysis of fusaproliferin and trichothecenes; thus, the calibrants should be prepared in a blank matrix. The response was linear in the range used. The mean recovery for fusaproliferin was 60.4 or 62.9%, depending on the spiking level. With respect to the trichothecenes, the recovery was generally higher (70.2-125.3%). The method proved to be repeatable for the analysis of fusaproliferin and trichothecenes. The limit of detection for fusaproliferin in the blank matrix mixture was 50 microg/kg, and that for trichothecenes was 5-15 microg/kg. Thirty-eight Finnish grain samples were analyzed for fusaproliferin and trichothecenes with the method developed. Fusaproliferin was not detected in any of the samples. The mean levels of deoxynivalenol, 3-acetyldeoxynivalenol, nivalenol, HT-2 toxin, and T-2 toxin in Finnish grain samples were 272, 17, 150, 40, and <20 microg/kg, respectively.  相似文献   

3.
Fusarium graminearum causes wheat head blight and contaminates grain with the trichothecenes 4-deoxynivalenol and nivalenol. Sequence analysis of trichothecene genes indicates that nivalenol production is the ancestral trait; however, deoxynivalenol producers occur worldwide and predominate in North and South America and in Europe. Analysis of a large field population (>500 strains) from Nepal identified three groups that were both genetically distinct and polymorphic for trichothecene production: SCAR1 comprising 95% deoxynivalenol producers, SCAR2 comprising 94% nivalenol producers, and SCAR3/5 comprising 34% deoxynivalenol producers/63% nivalenol producers. The ability to cause wheat head blight differed between SCAR groups and trichothecene chemotypes: deoxynivalenol producers were more virulent than nivalenol producers across all three SCAR groups and within the SCAR3/5 genetic background. These data support the hypothesis that production of deoxynivalenol rather than nivalenol confers a selective advantage to this important wheat pathogen.  相似文献   

4.
Small charcoal/alumina cleanup columns have been effectively used to remove interfering materials from grain, feed, and food extracts prior to chromatographic determination of trichothecene mycotoxins. A thin layer chromatographic method has been developed that can simultaneously detect part per billion concentrations of deoxynivalenol, fusarenon X, nivalenol, T-2 toxin, HT-2 toxin, neosolaniol, and diacetoxyscirpenol in food and feed samples. Recoveries of 90-99% can be obtained. The use of charcoal/alumina cleanup columns in conjunction with liquid chromatography and gas chromatography of trichothecenes is also discussed.  相似文献   

5.
《Cereal Chemistry》2017,94(2):315-324
Corn grain production could be affected by several fungal pathogens responsible for the production of mycotoxins. The aims of this study were to determine the evolution of phenolic acids and total antioxidant activity (TAA) during kernel development and to evaluate their potential protective role in minimizing mycotoxin contamination in six corn genotypes (four open‐pollinated varieties and two hybrids) characterized by a wide array of kernel traits. TAA and free and cell wall‐bound phenolics showed significant differences among corn genotypes at different stages of development, with the highest values found at the beginning of kernel development. Ferulic, p‐coumaric, and caffeic acids were the main cell wall‐bound phenolic acids during kernel development, whereas chlorogenic acid was the main free phenolic acid. A significant negative correlation was observed between deoxynivalenol contamination at harvest maturity and free phenolic acids and TAA at the beginning of kernel development, whereas no significant correlation was observed with fumonisin contamination. In conclusion, free phenolic acids are evidently involved in the resistance mechanism toward deoxynivalenol contamination, whereas their role toward fumonisin contamination was not elucidated under field conditions, implying that components other than phenolic acids may be responsible for this latter type of resistance.  相似文献   

6.
Samples of naturally contaminated hulled barley, with varying deoxynivalenol concentrations, were subjected to an abrasive type dehulling procedure. The remaining grain fractions were analyzed for weight remaining (%), deoxynivalenol (ppm), crude protein (%CP), neutral detergent fiber (%NDF), ash (%ASH), gross energy (GE; kcal/kg), and calculated digestible energy values (DE; kcal/kg). Following the initial 15 s of pearling, 85% of the grain mass remained. Additional pearling resulted in a linear decline of grain mass. Following 15 s of pearling, the grain contained 34% of the initial deoxynivalenol content, irrespective of the initial level of contamination. Further pearling resulted in continued significant (p < 0.05) reductions in the percent of deoxynivalenol remaining to a level of 7.9% after 120 s but with significant losses in grain mass. Pearling can serve as an effective means of reducing the deoxynivalenol content of barley, with improvements in nutrient levels. However, the need to reduce the deoxynivalenol content of contaminated barley to less than 1 ppm for swine will necessitate the removal of a significant amount of the grain mass for heavily contaminated samples.  相似文献   

7.
Two lots of human foodstuffs from conventional and organic brand foods were purchased from supermarkets and analyzed for three Fusarium toxins, deoxynivalenol, by GC-ECD, and fumonisins B(1) and B(2) (FB(1)-FB(2)), by LC-MS. The occurrence of deoxynivalenol contamination was higher than 80% in both organic and conventional foods; fumonisin B(1) was found in 20% of organic foods and in 31% of conventional ones and fumonisin B(2) in more than the 32% of the food samples from both the agricultural practices. The highest median concentration of deoxynivalenol occurred in conventional rice-based foodstuffs (207 microg/kg): that of fumonisin B(1) in conventional maize-based foods (345 microg/kg) and that of fumonisin B(2) in organic wheat-based foods (210 microg/kg).  相似文献   

8.
Resistance to mycotoxin contamination was compared in field samples harvested from 45 commercial corn (maize) hybrids and 5 single-cross aflatoxin-resistant germplasm lines in years with high and moderate heat stress. In high heat stress, mycotoxin levels were (4.34 +/- 0.32) x 10(3) microg/kg [(0.95-10.5 x 10(3) microg/kg] aflatoxins and 11.2 +/- 1.2 mg/kg (0-35 mg/kg) fumonisins in commercial hybrids and 370 +/- 88 microg/kg (140-609 microg/kg) aflatoxins and 4.0 +/- 1.3 mg/kg (1.7-7.8 mg/kg) fumonisins in aflatoxin-resistant germplasm lines. Deoxynivalenol was detected (one-fourth of the samples, 0-1.5 mg/kg), but not zearalenone. In moderate heat stress, mycotoxin levels were 6.2 +/- 1.6 microg/kg (0-30.4 microg/kg) aflatoxins and 2.5 +/- 0.2 mg/kg (0.5-4.8 mg/kg) fumonisins in commercial hybrids and 1.6 +/- 0.7 microg/kg (0-7 microg/kg) aflatoxins and 1.2 +/- 0.2 mg/kg (0.5-3.0 mg/kg) fumonisins in aflatoxin-resistant germplasm lines. The results are consistent with heat stress playing an important role in the susceptibility of corn to both aflatoxin and fumonisin contamination, with significant reductions of both aflatoxins and fumonisins in aflatoxin-resistant germplasm lines.  相似文献   

9.
Abstract

Studies were carried out on the growth of mould and the production of mycotoxins in grain during drying and storage. Various amounts of forced ambient air, 800, 600, 400, 200 and 0 m3 (air)/(hour ton), were used to dry wheat, which contained 32% moisture at harvest. Samples for mycological examination and determination of mycotoxins and moisture content were taken weekly. At harvest the mould flora consisted of various field fungi with less than 10% Fusarium spp. An increasing proportion of Aspergillius and Penicillium spp. were recorded in the bins at 0 and 200 m3 (air)/h t. The mycotoxin analysis indicated that the Fusarium spp. were also metabolically active until at least five weeks after the grain was put into the store room. The concentration of deoxynivalenol (DON) reached about 10 mg/kg after three weeks in the bins with no air flow, and about 2 mg/kg in the bins at 200 m3 (air)/h t. The zearalenone concentration also increased considerably, to about 5 mg/kg, in the bins with no air flow. The present results show that drying of grains using forced ambient air may produce good conditions for growth of field fungi as well as storage fungi if the flow of air is too low.  相似文献   

10.
Fusarium head blight (FHB) of wheat (Triticum aestivum L.), caused by the fungus Fusarium graminearum, is a major concern worldwide. FHB grain is reduced in yield, may fail to germinate, and is often contaminated with deoxynivalenol, a trichothecene mycotoxin linked to a variety of animal diseases and feed refusals. Annual losses in the tens of millions of dollars due to FHB underscore the need to develop improved methods of disease control and prevention. Previous research has identified deoxynivalenol biosynthesis as a virulence factor on wheat. Recently, we found that the TRI14 gene of F. sporotrichioides, closely related to F. graminearum, was not required for synthesis of a related trichothecene, T-2 toxin. TRI14 does not share similarity with any previously described genes in the databases. In this study, we examined the role that F. graminearum TRI14 may play in both deoxynivalenol synthesis and in virulence on wheat. TRI14 deletion mutants synthesize deoxynivalenol on cracked maize kernel medium and exhibit wild-type colony morphology and growth rate on complex and minimal agar media. However, FHB assays on greenhouse-grown wheat indicate that FgDeltaTri14 mutants cause 50-80% less disease than wild type and do not produce a detectable quantity of deoxynivalenol on plants. We discuss a number of possible roles that TRI14 may play in the disease process.  相似文献   

11.
In this study an LC-MS/MS multitoxin method covering a total of 247 fungal and bacterial metabolites was applied to the analysis of different foods and feedstuffs from Burkina Faso and Mozambique. Overall, 63 metabolites were determined in 122 samples of mainly maize and groundnuts and a few samples of sorghum, millet, rice, wheat, soy, dried fruits, other processed foods and animal feeds. Aflatoxin B(1) was observed more frequently in maize (Burkina Faso, 50% incidence, median = 23.6 μg/kg; Mozambique, 46% incidence, median = 69.9 μg/kg) than in groundnuts (Burkina Faso, 22% incidence, median = 10.5 μg/kg; Mozambique, 14% incidence, median = 3.4 μg/kg). Fumonisin B(1) concentrations in maize were higher in Mozambique (92% incidence, median = 869 μg/kg) than in Burkina Faso (81% incidence, median = 269 μg/kg). In addition, ochratoxin A, zearalenone, deoxynivalenol, nivalenol, and other less reported mycotoxins such as citrinin, alternariol, cyclopiazonic acid, sterigmatocystin, moniliformin, beauvericin, and enniatins were detected. Up to 28 toxic fungal metabolites were quantitated in a single sample, emphasizing the great variety of mycotoxin coexposure. Most mycotoxins have not been reported before in either country.  相似文献   

12.

Samples of winter wheat (n =84), winter rye (46) and barley (29) were collected from the larger family farms and from partnerships in Lithuania just after the 1998 harvest. The number of samples collected from each region was proportional to the amount of grain produced in it. The levels of the Fusarium toxins deoxynivalenol (DON), 3-acetyl-DON, 15-acetyl-DON, nivalenol (NIV), fusarenon-X (4-acetyl-NIV), T-2 toxin, HT-2 toxin, 4,5-diacetoxyscirpenol (DAS), 1,5-monoacetoxyscirpenol (MAS) and scirpentriol in the grain were determined by gas chromatography with mass-selective detection (GC-MS). DON was most often detected in the wheat and rye samples and NIV in the barley samples. The concentrations found were lower than those causing acute or chronic toxic effects in livestock or humans. No fusarenon-X or 15-acetyl-DON was detected, and only small amounts of other trichothecenes were present. Climatic conditions in Lithuania in the summer of 1998 were slightly cooler and wetter than the average for the 1992-1996 but were close to the norm. Because the samples analysed were representative of grain produced for the market in seasons with normal weather, trichothecene contamination of grain from large family farms and partnerships would not be expected to be a problem in most years.  相似文献   

13.
Rapid surface plasmon resonance-based inhibition assay of deoxynivalenol   总被引:7,自引:0,他引:7  
Deoxynivalenol belongs to a group of highly toxic fungal metabolites produced by Fusarium species that may contaminate food and animal feed, mostly grains. Three different monoclonal mouse anti-deoxynivalenol antibodies were compared for the development of a surface plasmon resonance (SPR)-based immunoassay for the selective and quantitative determination of deoxynivalenol in naturally contaminated matrices. A conjugate of deoxynivalenol with the protein casein was prepared and immobilized on the sensor chip surface. An excess of antibody was added to each test solution before the measurement. The assay was based on the competition for antibody binding between the immobilized deoxynivalenol conjugate on the sensor and the free deoxynivalenol molecules in the test solution. The deoxynivalenol-casein sensor could be reused more than 500 times without significant loss of activity using 6 M guanidine chloride solution for regeneration. The cross-reactivity of the three antibodies in the SPR assay was tested with other trichothecene mycotoxins (3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, nivalenol, HT2-toxin, and T2-toxin). The only sample preparation was extraction with max 80 vol % acetonitrile and 10-fold dilution with the running buffer. The assay had an optimal range between 2.5 and 30 ng/mL deoxynivalenol in the test solution. Most results of the SPR-based assay were in agreement with liquid chromatography/tandem mass spectrometry measurements of naturally contaminated wheat samples.  相似文献   

14.
Bioassays were used to determine the production of the trichothecene mycotoxin, deoxynivalenol (DON), by two isolates of Fusarium graminearum when grown in association with potentially competitive fungi and an antifungal chemical, 6-pentyl-alpha-pyrone (6PAP). The presence of 6PAP in the culture medium reduced DON production by as much as 80%, but this effect was reduced for the F. graminearum isolate that most efficiently metabolized the added 6PAP. A 6PAP-producing Trichoderma isolate grown in a competition assay system with the F. graminearum isolates was also able to substantially reduce DON production. When Fusarium isolates (F. crookwellense, F. culmorum, F. subglutinans, F. poae, F. equiseti, F. avenaceum, and F. sambucinum), which co-occur with F. graminearum in New Zealand maize plants (Zea mays), were grown in competition assays, the effect on DON production was variable. However, all isolates of F. subglutinans tested were shown to cause reductions in DON production (by 13-76%, mean = 62%). F. subglutinans frequently co-occurs with F. graminearum, but its presence can vary with location and time of the season. When the competitive fungus tested was also a trichothecene producer (e.g., of nivalenol), both toxins were produced in the assay medium. The results indicate that mycotoxin production by F. graminearum can be affected by the presence of particular competitive fungi. These results have implications for an ecological understanding of pathogenicity and of mycotoxin accumulation in plants. Early establishment of F. subglutinans, for example, may act as a biological control mechanism providing a temporary protection against invasion by more commonly toxigenic fusaria such as F. graminearum.  相似文献   

15.
在大田栽培条件下,运用15N示踪技术研究了不同施氮量和底追肥比例对小麦氮素利用和子粒产量及蛋白质含量的影响。结果表明,施用氮肥提高了小麦植株的氮素积累量、子粒产量、蛋白质含量和蛋白质产量。相同施氮量条件下增加追肥氮的比例,提高了氮肥农学利用率和吸收利用率,增加了植株地上部器官(子粒+营养器官)中追肥氮、土壤氮的积累量,提高了营养器官中氮素的转运量和开花后氮素的同化量,增加了子粒蛋白质含量。相同的氮素底追肥比例条件下,将240.kg/hm2施氮量降至168.kg/hm2的处理,氮肥农学利用率、氮肥吸收利用率、氮肥偏生产力提高,子粒中土壤氮的积累量增加,植株地上部器官中土壤氮的积累量亦增加,开花后氮素同化量提高,子粒蛋白质含量增加。各施氮处理间子粒产量无显著差异。在本试验条件下,施氮量为168.kg/hm2且全部于拔节期追施是兼顾产量、品质和效益的优化处理。  相似文献   

16.
Cross-reactivity of antibodies in AGRAQUANT, DON EIA, VERATOX, ROSA LF-DONQ, and MYCONTROLDON designed for deoxynivalenol (DON) determination in food and feedstuffs was evaluated against nivalenol, 3-acetylDON, 15-acetylDON, de-epoxy metabolite 1 of DON, DON-3β-glucoside, T2-toxin, HT2-toxin, fusarenone X, diacetoxyscirpenol, verrucarol, and zearalenone. Cross-reactivity measurements were run in water using the 50% reduction of absorbance of the blank for ELISA kits or through direct DON determination upon using the standards of mycotoxins via ROSA LF-DONQ or MYCONTROLDON. For the tested toxin concentrations, all DON kits have low cross-reactivity toward diacetoxyscirpenol, T2-toxin, HT2-toxin, verrucarol, and zearalenone and moderate cross-reactivity toward 15-AcetylDON and fusarenone X. AGRAQUANT, DON EIA, and VERATOX kits showed high cross-reactivity in various ranking orders against DON-3-Glc, DOM-1, and 3AcDON. DON EIA showed also high cross-reactivity against nivalenol and fusarenone X. These mycotoxins could coexist in food or feedstuffs, and analytical results can be wrongly interpreted. Cross-reactivity does not allow checking the compliance with the legal norms, but it does allow an overall risk assessment for the consumers. Updating regularly the cross-reactivity evaluation of the produced batches is recommended for 3-acetylDON, nivalenol, DON-3-Glc, de-epoxy metabolite 1, and fusarenone X.  相似文献   

17.
Deoxynivalenol (DON) is a toxic secondary metabolite produced by molds of the Fusarium genus and is known to cause a spectrum of diseases in animals such as vomiting and gastroenteritis. It is found in cereals and cereal products as most processing techniques lead only to a partial reduction of deoxynivalenol levels. One technique with a reported relatively high impact on deoxynivaleol decomposition is extrusion cooking. In the current work, systematic studies of a range of physicochemical parameters, such as temperature, moisture, compression, residence time in the extruder, pH value, and protein content, on their impact on deoxynivalenol decomposition during extrusion cooking were performed. The analysis of deoxynivalenol was made by high-performance liquid chromatography--tandem mass spectrometry using a quick, easy, cheap, effective, rugged, and safe-based cleanup with 15-d(1)-deoxynivalenol as an internal standard. It could be shown that the reduction of deoxynivalenol levels is dependent on a set of parameters partially interacting with each other. Especially the moisture content and compression are key factors for the reduction of deoxynivalenol levels. A correlation between residence time of the mycotoxin in the extruder and deoxynivalenol degradation was also observed when screws without a compression factor were used. Generally, the reduction of deoxynivalenol levels was increased by the use of screws with a high compression factor. As known from cooking, deoxynivalenol could also be easily degraded by extrusion under alkaline conditions. Furthermore, an increase of the protein content of the starting material resulted in higher reduction rates of deoxynivalenol.  相似文献   

18.
The production of fusaproliferin (FUS), a recently described mycotoxin, and beauvericin (BEA), a mycotoxin recently reported to co-occur with FUS in Fusarium-infected corn, by South African isolates in the Fusarium section Liseola, was investigated. Five isolates each of F. verticillioides, F. proliferatum, F. subglutinans, and F. globosum were cultured on corn kernels. Four each of the five South African isolates of F. proliferatum and F. subglutinans produced FUS (10-1725 and 330-2630 mg/kg, respectively). BEA was produced by four of the F. proliferatum strains (310-1130 mg/kg) and three of the F. subglutinans strains (140-700 mg/kg). The isolates of F. verticillioides failed to produce significant levels of either of these secondary metabolites. F. globosum was a weak producer of both in that one isolate of five produced 25 mg/kg FUS and five out of five produced BEA at levels ranging between 10 and 110 mg/kg. To further characterize these strains, their production of fumonisins B(1), B(2), and B(3), as well as moniliformin, was investigated. Of the four species investigated, fumonisins were produced by all except F. subglutinans, which in turn was the only species whose isolates in this study produced moniliformin (four of five isolates, ranging from 155 to 2095 mg/kg). Analysis of visibly Fusarium-infected home-grown corn collected in the Transkei region of the Eastern Cape Province of South Africa showed that nine of the ten samples contained low levels of FUS (up to 62 microg/kg), whereas all ten samples showed BEA contamination ranging from 8 to 1734 microg/kg with a mean of 258 microg/kg.  相似文献   

19.
王飞  林诚  李清华  何春梅  林新坚 《土壤》2017,49(5):882-887
冷浸田为福建省主要低产田类型之一。基于福建省浅脚烂泥田、青泥田与锈水田主要冷浸田类型,通过田间3个点试验研究不同氮肥用量(105、150与195 kg/hm~2)与施用时期(基蘖肥︰穗肥=10︰0与基蘖肥︰穗肥=7︰3)运筹组合对单季稻生长的影响。结果表明,增施氮肥促进了各类型冷浸田水稻分蘖期分蘖生长速率。不同氮肥组合的锈水田、青泥田与浅脚烂泥田水稻籽粒产量分别较不施肥(CK)增幅14.5%~45.5%、9.4%~13.5%和10.4%~15.9%,但在105 kg/hm~2用量基础上再进一步增施氮肥,籽粒增产效果明显放缓。施用氮肥显著增加了成熟期水稻有效穗数,但对每穗实粒数及千粒重影响不明显。105、150、195 kg/hm~2 3种氮肥用量下各类型冷浸田的农学效率均值分别为17.4、13.3与12.8 kg/kg。除浅脚烂泥田施用穗肥的秸秆产量有显著差异外,其余氮肥不同施肥时期的籽粒与秸秆产量均无显著差异。增施氮肥有提高籽粒氮的趋势,但同时降低了籽粒钾含量。鉴于冷浸田土壤氮素水平较高,单季稻氮肥经济用量宜控制在105~150 kg/hm~2中低水平,超过150 kg/hm~2,农学效率递减,且无明显增产效果。另从人工成本及效益考虑,宜选择基蘖肥︰穗肥=10︰0的施氮方式。  相似文献   

20.
【目的】研究不同磷、钾肥施用量和施用方法对稻茬小麦籽粒产量、蛋白质含量和氮、磷、钾素吸收与利用的影响,为稻茬小麦增产增效提供参考。【方法】2020—2021年在江苏仪征市进行小麦田间试验,种植制度为稻麦轮作,供试小麦品种为弱筋型‘宁麦33’,该地块稻麦秸秆长期全部还田。试验采用裂区设计,主区为磷肥,分别设置3个一次基施磷(P) 0、72和144 kg/hm2处理(分别为P0、P1、P2)和1个基施与拔节期追施磷(P)各72 kg/hm2处理(P3);钾为副区,设置3个一次基施钾(K) 0、72和144 kg/hm2处理(K0、K1、K2)和1个基施与拔节期施钾(K)各72 kg/hm2处理(K3)。小麦收获后,调查生物量与籽粒产量,分析植株和籽粒中氮磷钾含量和籽粒蛋白质含量。【结果】施磷、钾肥对植株氮、磷、钾养分积累量、养分利用效率、籽粒产量和蛋白质含量有显著效应和交互效应,适量的磷、钾肥(72 kg/hm2)配施有助于量质效协同提升,而过量施用(144kg/hm2<...  相似文献   

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