Inês Almeida

Fumonisins and deoxynivalenol in corn-based food products in Portugal

A great diversity of crops is vulnerable to fungal attack and might be contaminated with mycotoxins. Currently it is estimated that 25% of the worlds harvest production is contaminated to some level with these toxins. The presence of fumonisins and deoxynivalenol in corn-based foods, available in Portugal, was analyzed in order to produce some data that may be useful for hazard characterization. A total of 105 samples were screened, including, corn meal (41), sweet corn (49) and corn flakes (15). None of the 15 samples of corn flakes contained some detectable amount of fumonisins. However, fumonisin B1 (FB1) and fumonisin B2 (FB2) contamination was found in 100.0% and 70.7% of the corn meal samples, respectively. Sweet corn samples were positive in 73.4% for FB1, although no FB2 was detected. The highest levels of fumonisin were found in corn meal (maximum: 1300 microg FB1/kg and 450 microg FB2/kg). The presence of deoxynivalenol was not detected in any of the analyzed samples. Nevertheless these results indicate the need to establish, by corn products manufacturers, a continuous monitoring program to prevent and manage the occurrence of these contaminants.

Mycotoxins in feedstuffs in Portugal: an overview

Mycotoxins are secondary metabolites produced by many genera of fungi in many commodities, under certain conditions. Mycotoxicological control of feed is a procedure that aims to protect human and animal health, avoiding the adverse effects of these undesirable substances. This component of the sanitary control of feed and food is essential to prevent the presence of those substances which can seriously affect the health of the animals. In Portugal, there is relatively few information related to the natural occurrence of mycotoxins in feed. In this context, the authors present results and data compilation concerning the occurrence of mycotoxins in raw materials and also feed for dairy cattle, swine, poultry, horses, fish, laboratory rats and pet; making a generic qualitative appreciation of the risks associated to the presence of mycotoxins in these feedstuffs. The mycotoxins studied: aflatoxins (AFs), ochratoxin A (OTA), fumonisin B1 and B2 (FB1, FB2) were analysed by High Performance Liquid Chromatoghraphy (HPLC). Deoxynivalenol (DON) and zearalenone (ZEN) were determined by Thin-Layer Chromatography (TLC). The results suggest that contaminations with these mycotoxins in feed are quite common, revealing the need for surveillance and monitoring programs for the prevention of the sanitary impacts of these “non desirable substances”.

Mycobiota and aflatoxin B1 in feed for farmed sea bass (Dicentrarchus labrax).

Thesafety characteristics of feed used in fish and crustacean aquaculture systems are an essential tool to assure the productivity of those animal exploitations. Safety of feed may be affected by different hazards, including biological and chemical groups. The aim of this preliminary study was to evaluate fungi contamination and the presence of aflatoxins in 87 samples of feed for sea bass, collected in Portugal. Molds were found in 35 samples (40.2%) in levels ranging from 1 to 3.3 log10 CFU∙g−1. Six genera of molds were found. Aspergillus flavus was the most frequent, found in all positive samples, with a range from 2 to 3.2 log10 CFU∙g−1. Aspergillus niger was found in 34 samples (39.1%), ranging from 1 to 2.7 log10 CFU∙g−1. Aspergillus glaucus was found in 26 samples (29.9%) with levels between 1 and 2.4 log10 CFU∙g−1. Penicillium spp. and Cladosporium spp. were both found in 25 samples (28.7%). Fusarium spp. was found in 22 samples (25.3%), ranging from 1 to 2.3 log10 CFU∙g−1. All feed samples were screened for aflatoxins using a HPLC technique, with a detection limit of 1.0 μg∙kg−1. All samples were aflatoxin negative.

Occurrence of fumonisins in feed for swine and horses.

BACKGROUND Fumonisin B1 (FB1), fumonisin B2 (FB2), and overall mycotoxins feed contamination may cause several effects on crops production and animal health. The contamination occurred predominantly in corn and corn-based foods and feeds. AIMS This survey intends to provide the occurrence of fumonisins in swine and equine mixed feeds in Portugal, making an overview from 2007 to 2010. METHODS A total of 363 samples were analyzed, 258 from swine feed and 105 from horse feed with HPLC method. The detection limit was 50 μg/kg for FB1 and 100 μg/kg for FB2. RESULTS The overall results were 13% of FB1 occurrence from 2007 to 2010. FB1 was detected in about 17.0% of swine feed samples, being more frequent in 2010 (32.9%). In this year (2010) levels ranged between 66.7 and 3815.5 μg/kg. FB2 occurred only in 2010 in swine feed (6 samples, ranging between 104.0 to 467.2 μg/kg) and in horse feed (1 sample). CONCLUSIONS This represents an increase in occurrence through the analyzed years, but this may not be a threat to animal health, once the values were below the recommended guidance values from European Commission.