The aim of this study was to assess variations in aggressiveness and
trichothecene production of F. graminearum isolates originating from maize,
wheat and barley in Serbia. Analyzing F. graminearum ...isolates (98) obtained
from various agroecological conditions of Serbia over the period from 1993
to 2010, using the HPLC method, the following two chemotypes were observed:
3-acetyl-deoxinivalenol (3ADON) and 15-acetyl-deoxinivalenol (15ADON). A
great diversity in the production of deoxinivalenol (DON) derivatives was
observed. A majority of F. graminearum isolates, regardless of their origin
(maize, wheat or barley) belonged to the 15ADON chemotype. The 3ADON
chemotype was also detected, but in a significantly smaller number (13/98)
samples, compared to the 15ADON chemotype (85/98). None of the tested
isolates belonged to the NIV chemotype. The examined isolates showed
different pathogenicity on barley leaf, wheat class and maize ears. The
average pathogenicity of the tested isolates was the highest on barley leaf.
It was observed that isolates originating from wheat had the highest average
daily increase in mycelium growth rate (27.37 mm). Statistical analysis of
the obtained results for mycotoxins synthesis showed that there was a highly
significant statistical correlation between the production potentials of
total DON, 3ADON and 15ADON in F. graminearum isolates belonging to various
chemotypes. However, there was no statistically significant correlation
between the aggressiveness of isolates and the production of total DON in
isolates belonging to 3ADON and 15ADON chemotypes.
► We detected deoxynivalenol in 66.4% of wheat samples analysed. ► The total estimated daily intake of DON in Londrina, Brazil was 1.13μg/kg/day. ► Constant monitoring on mycotoxin levels is ...necessary to minimise health risks.
The occurrence of deoxynivalenol (DON) was evaluated in 113 wheat samples from the northern and central/southwestern regions of Paraná State, Brazil during the 2008 and 2009 growing seasons, and this rate of occurrence was used to estimate the DON dietary exposure. The DON determination was carried out by an indirect competitive enzyme-linked immunosorbent assay. DON was detected in 66.4% samples at levels ranging from 206.3 to 4732.3μg/kg (mean 1894.9μg/kg). The estimated daily intake (EDI) of DON through bread and pasta was evaluated in the inhabitants of Londrina City in northern Paraná State, Brazil. The average intake of these inhabitants was 0.79μg/kg body weight (b.w.) for bread and 0.35μg/kgb.w. for pasta. The total EDI was 1.13μg/kg, which is above the Provisional Tolerable Daily Maximum Intake (PTDMI) of 1μg/kgb.w. To our knowledge, this is the first report on natural DON occurrence in wheat and DON dietary exposure estimation from Paraná, Brazil.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The protective effect of polysaccharide glucan in chickens fed low doses of T-2 toxin was assessed. The binder effect of β-D-glucan on jejunal mucosa in relation to the expression of Na
+
/K
+
...-ATPase, proliferative activity of enterocytes and number of goblet cells was investigated. A total of 40 one-day-old chickens were allocated to four groups: control (C), β-D-glucan (G), T-2 toxin (T) and combined β-D-glucan+T-2 toxin (GT). The chickens were individually administrated
per os
1.0 mg/bird/day of β-D-glucan derived from
Candida albicans
on days 11, 12, and 21 of the experiment (totally 3 mg per bird). T-2 toxin at a concentration of 1.45 μg·kg
-1
was added to the feed from day 14 to day 28 of the experiment. The α subunit-specific anti-Na
+
/K
+
-ATPase antibody was used to identify the protein by immunofluorescence in the cell membrane of jejunal enterocytes. Higher expression of Na
+
/K
+
-ATPase was found in the jejunal epithelial cells and lamina propria in the chickens fed T-2 toxin and administered glucan (
P
< 0.05) compared to control. The number of proliferated enterocytes was higher in group T compared to group G and control (
P
< 0.001), as well group GT (
P
< 0.01). Goblet cell density did not present significant differences between groups of chickens, but group G showed the highest values. These data suggest that administration of pure T-2 toxin at low doses affects primarily the protein synthesis of actively dividing cells. Higher distribution of Na
+
/K
+
-ATPase in enterocytes of chickens in GT group suggests positive influence of glucan and mycotoxin on the ion pump. A binding effect of this immunomodulator on the digestive tract mucosa in the applied setup was not observed.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Metabolic pathways of T-2 toxin Dohnal, Vlastimil; Jezkova, Alena; Jun, Daniel ...
Current drug metabolism
9, Issue:
1
Journal Article
Peer reviewed
Among the naturally-occurring trichothecenes found in food and feed, T-2 toxin is the most potent and toxic mycotoxin. After ingestion of T-2 toxin into the organism, it is processed and eliminated. ...Some metabolites of this trichothecene are equally toxic or slightly more toxic than T-2 itself, and therefore, the metabolic fate of T-2 toxin has been of great concern. The main reactions in trichothecene metabolism are hydrolysis, hydroxylation and deep oxidation. Typical metabolites of T-2 toxin in an organism are HT-2 toxin, T-2-triol, T-2-tetraol, 3'-hydroxy-T-2, and 3'-hydroxy-HT-2 toxin. There are significant differences in the metabolic pathways of T-2 toxin between ruminants and non-ruminants. Ruminants have been more resistant to the adverse effects of T-2 toxin due to microbial degradation within rumen microorganisms. Some plant species are resistant to T-2 toxin, while others are capable of its intake and metabolisation.
Fusarium head blight (FHB) is a widespread, destructive disease of wheat and barley that is primarily caused by Fusarium graminearum Schwabe. F. graminearum produces mycotoxins such as deoxynivalenol ...(DON) and nivalenol (NIV) in infected grain. Fungicide application is the most practical way to control FHB, but it is not consistently effective. To obtain better chemical control, the timing of application is important. In both wheat and barley, FHB fungicides have been usually applied at or near anthesis (flowering stage) regardless of the cultivar because this stage in wheat is most susceptible. However, we found that in barley the most critical time for F. graminearum infection and mycotoxin accumulation differs among cultivars. Whereas chasmogamous (open-flowering) cultivars were most susceptible at anthesis, cleistogamous (closed-flowering) cultivars showed good resistance at anthesis, but were relatively susceptible after ‘spent’ anther extrusion (SAE). As expected from these observations, field experiments using thiophanate-methyl fungicide indicated that the optimal timing for chemical control in cleistogamous barley is around the beginning of SAE, rather than at anthesis. For wheat, the manner in which DON and NIV accumulate in grain infected with F. graminearum and the influence of the time of infection on mycotoxin accumulation were investigated. High levels of DON and NIV were produced in grain beyond 20 days after anthesis. This indicates the importance of the late stage of grain development in mycotoxin contamination in wheat, suggesting that control strategies that cover both the early and late stages of grain development should be developed.
Ten
Fusarium sporotrichioides
strains from different geographic regions were analyzed by RAPD in order to detect DNA loci potentially suitable as new markers for taxonomic characterization and ...identification of toxigenic
Fusarium
fungi. Three monomorphic fragments were selected from PCR amplificates obtained with one of the standard RAPD primers and sequenced. Analysis of the sequences enabled the development of specific SCAR markers for identification of
Fusarium
fungi at the level of species groups characterized by similar profiles of produced mycotoxins.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The interest of this present work is to compare two selected durum wheat lines (G1 and G4) with their sensitive parents to fusarium head blight by determining the mycotoxin and ergosterol content in ...their mature grains. These lines are homozygous, fixed, obtained by the classical genealogical selection, and composed of seeds from diallel crosses between 4 parental varieties Saadi, Simeto, Ardente, and Waha. For this purpose, the grains of the studied genotypes (lines and parental varieties) were tested in the laboratory for their content of Trichothecenes B mycotoxins (TCTB) and ergosterol at full grain maturity using high-performance liquid chromatographic – diode array detection (HPLC-DAD). Fungal biomass was estimated by the content of ergosterol. However, the level of toxins was assessed by the levels of TCTB produced by the different studied isolates. The results obtained showed that the lines derived from crosses and, especially the G1 line, accumulated levels of TCTB and ergosterol significantly lower than their parents. Our findings open up a new avenue of investigation into fusarium head blight in Algeria, including the search for mycotoxins as potential causes of poorly understood human diseases and the factors that contribute to their accumulation in grains.
Mycotoxigenic fungi and their toxins are a global concern, causing huge economic and health impacts in developing countries such as Ethiopia, where the mycotoxin control system is inadequate. This ...work aimed to review the occurrences of agriculturally essential fungi such as
,
, and
and their major mycotoxins in Ethiopian food/feedstuffs. The incidents of crucial toxins, including aflatoxins (B1, B2, G1, G2, M1), fumonisins (B1, B2), zearalenone, deoxynivalenol, and ochratoxin A, were studied. The impacts of chronic aflatoxin exposure on liver cancer risks, synergy with chronic hepatitis B infection, and possible links with Ethiopian childhood malnutrition were thoroughly examined. In addition, health risks of other potential mycotoxin exposure are also discussed, and the impacts of unsafe level of mycotoxin contaminations on economically essential export products and livestock productions were assessed. Feasible mycotoxin mitigation strategies such as biocontrol methods and binding agents (bentonite) were recommended because they are relatively cheap for low-income farmers and widely available in Ethiopia, respectively. Moreover, Ethiopian mycotoxin regulations, storage practice, adulteration practice, mycotoxin tests, and knowledge gaps among value chain actors were highlighted. Finally, sustained public awareness was suggested, along with technical and human capacity developments in the food control sector.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The principal agents of Fusarium head blight in the main cropping area of Argentina were investigated in heavily infected samples. The ability of the isolates to produce trichothecenes was determined ...by GC and HPLC. Fusarium graminearum was the predominant species and of 33 isolates, 10 produced deoxinivalenol (DON) (0.1- 29 mg kg(-1)), 13 produced both deoxinivalenol (1.0- 708 mg kg(-1)) and nivalenol (0.1- 6.2mg kg(-1)), 12 produced 3-acetyldeoxinivalenol (0.1- 14 mg kg(-1)), 13 produced 15-acetyldeoxinivalenol (0.1- 1.9 mg kg(-1)), 10 produced Fusarenone X (0.1- 2.4 mg kg(-1)) and 7 produced zearalenone (0.1- 0.6 mg kg(-1)). These results suggest that F. graminearum strains isolated from the wheat growing regions in Argentina belong to DON chemotype. Although some strains produced both deoxinivalenol and nivalenol, nivalenol was produced in lower levels. The natural occurrence of nivalenol in wheat affected by head-blight collected in the main production area during two years (2001-2002) was also determined. From 19 samples 13 were contaminated with deoxinivalenol in a range of 0.3 to 70 mg kg(-1)and 2 samples with both deoxinivalenol (7.5 and 6.7 mg kg(-1)) and nivalenol (0.05 and 0.1 mg kg(-1)), respectively. This is the first report of natural occurrence of nivalenol in wheat cultivate in Argentina.
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