Screening survey of deoxynivalenol in beer from the European market by an enzyme-linked immunosorbent assay.

Deoxynivalenol (DON) was analysed in 313 beer samples collected from the European retail market using a commercially available immunoassay kit (enzyme-linked immunosorbent assay, ELISA). The incidence rate was about 87%, while most samples (73%) had contamination levels lower than 20 ng m(-1). The contamination ranged between 4.0 and 56.7 ng ml(-1), with an average of 13.5 ng ml(-1). A statistically significant correlation between alcohol levels and DON contamination was found, as well as a significant difference between bottom, top and spontaneous fermenting beers. Twenty-seven beer samples were compared using a second ELISA kit and a good correlation was obtained between the two kits (r = 0.93). Although when compared with gas chromatography-mass spectrometry the ELISA tended to overestimate the results, a good correlation (r=0.94) between the two methods was observed. Monitoring of DON in beer is important considering that DON production is dependent on the weather and that it can contribute significantly to the tolerable daily intake of DON, especially for frequent beer consumers.

Occurrence of fumonisin B1 in Bulgarian maize samples determined by ELISA and TLC methods using different clean up steps.

An enzyme linked immunosorbent assay (ELISA) method and a thin-layer chromatography (TLC) method with two different clean-up procedures have been used to analyse maize samples (food and feeding stuff) obtained from Bulgaria. The occurrence of Fumonisin B1 in Bulgarian maize was found to be in the range of what was reported for other European regions with a mean value of 1.5 mg/kg, 2.1 mg/kg and 1.8 mg/kg when analysed by ELISA and thin-layer chromatography with solid phase extraction clean up and immunoaffinity clean up, respectively. It was shown that results of the different methods are comparable, indicating that the methods applied are sufficiently reliable tools for the simple and rapid screening of maize samples.

Co-occurrence of ochratoxin A and citrinin in cereals from Bulgarian villages with a history of Balkan endemic nephropathy.

Cereal samples were collected in 1998 from Bulgarian villages without [control village (C), n = 20] or with [endemic villages (E); E1, n = 21; E2, n = 30; E3, n = 23] a history of Balkan endemic nephropathy (BEN). Sampling included foods (wheat, corn) and feeds (barley, oats, wheat bran). Analysis of ochratoxin A and citrinin was done by enzyme immunoassays (EIA), with detection limits of 0.5 and 5 ng/g, respectively. Ochratoxin A-positive results were confirmed by HPLC after immunoaffinity chromatography. Highest toxin levels were found in wheat, wheat bran, and oats. For ochratoxin A, the percentages of positives were 35% (C), 29% (E1), 30% (E2), and 47% (E3), the mean/median values of positives were 1.5/1.3 ng/g (C), 11/1.6 ng/g (E1), 18/1.6 ng/g (E2), and 3.5/1.5 ng/g (E3). For citrinin, 5.0% (C), 14% (E1), 3.3% (E2), and 13% (E3) were positive, and the mean/median values were 6.1/6.1 ng/g (C), 180/83 ng/g (E1), 10/10 ng/g (E2), and 84/20 ng/g (E3). Highest concentrations of ochratoxin (maximum = 140 ng/g) and citrinin (maximum = 420 ng/g) were found in samples from endemic villages. Co-contamination with ochratoxin A and citrinin was found for one sample (14% of positives) from village C and for six samples (22% of positives) from villages E1-E3. Citrinin levels in these samples were 2-200 times higher than those of ochratoxin A.

[Mycotoxins in spices]. / Mikotoksiny v pripravakh.

Since antiquity, spices have been used for flavoring foods and beverages and for medication. They play an important role in the national economy of several of the producing, exporting and importing countries. Tropical climatic conditions under which spices are grown offer a favorable environment for the fungal and mycotoxin contamination. This review summarized information from 44 reports on the occurrence of mycotoxins (aflatoxins, ochratoxins zearalenone, fumonisins, trichothecenes) and their levels in different spices. Aflatoxins which are highly carcinogenic compounds, produced by A. flavus and A. parasiticus, are the leading toxins present in red peppers (paprika, chilli, cayenne) nutmeg, mustard, ginger, black and white peppers, coriander. Ochratoxins have been reported also as a natural contaminants in many spices. Although the levels of mycotoxins are generally low when compared with other food products, the testing of spices (imported and domestic) by regulatory agencies seems to be in need of expansion.

Citrinin in the diet of young and healthy persons living in balkan endemic nephropathy areas.

The dietary citrinin (CT) intake of 19 persons living in highrisk "Balkan Endemic Nephropathy" areas in Bulgaria was studied. Over 4 weeks, volunteers collected aliquots of their daily meals. Weekly samples were homogenized and analysed for CT by enzyme immunoassay (detection limit: 1ng/g). CT was found at least once in the weekly diet of 11 persons, maximum levels were at 6 ng/g. Considering the total amount of food consumed, the weekly CT intake of several persons exceeded 10 microgram. The data suggest that people living in high-risk nephropathy areas are exposed to dietary CT at considerable levels.

First survey on the natural occurrence of Fusarium mycotoxins in Bulgarian wheat.

Wheat for human consumption (140 samples) was collected after harvest from all regions of Bulgaria. The 1995 crop year was characterized by heavy rainfall in the spring and summer months. The internal mycoflora of wheat samples was dominated by Fusarium spp. and Alternaria spp., and storage fungi were rarely present. The samples were analysed for contamination with Fusarium mycotoxins deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-AcDON), 15-acetyldeoxynivalenol (15-AcDON), T-2 Toxin (T-2), diacetoxyscirpenol (DAS), and zearalenone (ZEA), using enzyme immunoassay methods. DON and ZEA were the predominant toxins, with a contamination frequency of 67% and 69%, respectively. The average levels of these toxins in positive samples were 180 micrograms/kg (DON) and 17 micrograms/kg (ZEA), maximum concentrations were 1800 micrograms kg-1 and 120 micrograms kg-1, respectively. Acetyl derivatives of DON, namely 3-AcDON and 15-AcDON, were found in 2.1% and 0.7% of the samples, at at maximum level of about 100 micrograms kg-1. Only one sample was positive for T-2 (55 micrograms/kg), DAS was not detected. This is the first report about the natural occurrence of a range of Fusarium mycotoxins in wheat for human consumption in Bulgaria.