ABSTRACT
Samples of wheat harvested from 1988 to 1990 and stored in elevators in the south of Brazil (12 Brazilian, 4 Argentinian and 2 Uruguayan) were analysed in 1990 for 14 mycotoxins: deoxynivalenol (DON), nivalenol, diacetoxyscirpenol (DAS), T-2 and HT-2 toxins, T-2 triol, T-2 tetraol, aflatoxins B1, B2, G1, G2, ochratoxin A (OCHRA A), zearalenone and sterigmatocystin. One sample (1988 harvest) was contaminated with OCHRA A (0.04 microgram/g) and three other samples (1990 harvest) were contaminated with DON (0.40 microgram/g), DAS (0.30 microgram/g), T-2 (two samples, 0.35 and 0.36 gamma g/g) and T-2 tetraol (1.68 micrograms/g). Fusarium graminearum Schwabe was found in the 1990 samples with a relative incidence ranging from 1 to 22% and predominated in Argentinian and Uruguayan wheat (1990 harvest). Fusarium dimerum Penzig (8-75%) was the main Fusarium sp. in Brazilian wheat from the 1990 harvest.
Subject(s)
Food Contamination , Fungi/isolation & purification , Mycotoxins/analysis , Triticum/chemistry , Triticum/microbiology , Brazil , Food Preservation , Fusarium/isolation & purification , Ochratoxins/analysis , Trichothecenes/analysisABSTRACT
Wheat from two cultivars with contrasting characteristics were harvested in ten experimental plots located in wheat producing areas of the State of São Paulo, Brazil. The samples (10 of each cultivar) were analyzed by a gas-chromatographic method for deoxynivalenol (DON), nivalenol (NIV), diacetoxyscirpenol (DAS), toxins T-2 (T-2) and HT-2, T-2 tetraol, T-2 triol, and by a thin-layer chromatographic method for zearalenone (ZEN), aflatoxins B1, B2, G1, G2, ochratoxin A and sterigmatocystin. No mycotoxins were detected in 13 samples. DON was found in four samples (0.47-0.59 microgram/g), NIV in three samples (0.16-0.40 microgram/g), T-2 in two samples (0.40, 0.80 microgram/g), DAS in one sample (0.60 microgram/g), and ZEN in three samples (0.04-0.21 microgram/g). The wheat samples were also examined for the incidence of fungi. Alternaria, Drechslera, Epicoccum and Cladosporium were the prevailing genera. Among the Fusarium spp., F. semitectum was present in 19 samples and F. moniliforme in 18 samples. No F. graminearum was isolated in the samples.
