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Contamination of animal feed with mycotoxins still occurs very often, despite great efforts in preventing it. Animal feeds are contaminated, at low levels, with several mycotoxins, particularly with those produced by Aspergillus and Fusarium genera (Aflatoxin B Ochratoxin A, Zearalenone, Deoxynivalenol and Fumonisina B). In animal feed, to date, only Aflatoxin B is limited through EU regulation. Consequently, mycotoxins cause serious disorders and diseases in farm animals. In 2009, the European Union (386/2009/EC) approved the use of mycotoxin-detoxifying agents, as feed additives, to prevent mycotoxicoses in farm animals. The present review gives an overview of the problem of multi-mycotoxin contamination of feed, and aims to classify mycotoxin adsorbing agents (minerals, organic, and synthetic) for feed decontamination, focusing on adsorbents with the ability to bind to multiple mycotoxins, which should have a more effective application in farms but they are still little studied in scientific literature.

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The effects of water activity (aw, 0.994-0.90 identical to 0.4-14.0 (-)MPa water potential), temperature (4-45 degrees C), and pH (3.6, 5.5, 7.0), and their interactions on growth of isolates of Fusarium moniliforme and Fusarium proliferatum were determined in vitro on a maize extract agar medium. Growth of two isolates of F. moniliforme and four isolates of F. proliferatum were significantly influenced by water activity regardless of solute type used (NaCl, glycerol, or glucose). However, at steady-state aw levels, growth was optimum at 0.994-0.98 aw and reduced significantly at 0.92 aw. Further detailed studies with one isolate of F. moniliforme (25N) and two isolates of F. proliferatum (73N, 131N) showed that growth occurred over the range of 0.994-0.90 aw in the temperature range 20-35 degrees C with slight differences between species. Growth did occur at 4 degrees C and 0.994-0.96 aw, but no growth was recorded at 40 and 45 degrees C regardless of aw. Profiles of aw x temperature relations for growth of these two species were constructed from these data for the first time. Optimum pH and temperature for growth was 5.5 and 25 degrees C for both isolates of F. proliferatum, and pH 7.0 and 30 degrees C for the isolate of F. moniliforme. However, for the latter isolate at < 0.98 aw, optimum pH and temperature for growth changed. The effects of pH, temperature, and aw for single, two-way and three-way interactions were all found to be statistically significant for these three isolates. The ecological significance of this information for understanding these important fumonisin-producing fungi is discussed.

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Aims: The effects of water activity (0AE90-0AE99 a w ), temperature (15-37°C), and their interaction on growth and ochratoxin A (OTA) production by eight isolates of Aspergillus carbonarius were investigated on synthetic nutrient medium (SNM) with composition similar to grapes. Methods and Results: Growth data were modelled by an multiple linear regression and response surface models were obtained. Aspergillus carbonarius grew much faster at 30°C than at the other temperature levels tested and its growth rate increased with increasing a w , maximum growth rate being between 0AE95 and 0AE99 a w . In general, isolates grew faster at 35-37°C than at 20°C, although no significant differences were found between these temperatures. OTA accumulation was also favoured by high a w levels, and although it was observed in the whole range of temperatures, maximum amounts were detected at 20°C. No OTA was found at the most unfavourable growth conditions. Conclusions: Optimum a w level for growth seems to correspond with optimum for OTA production, meanwhile the most propitious temperature for the toxin production was below the best one for growth. Significance and Impact of the Study: Prediction of A. carbonarius growth would allow estimating their presence and therefore, the OTA production, as it was found that conditions for the toxin production were more limited than those permitting growth.

Aims: To investigate the volatile fractions of 16 essential oils for activity against the more common fungi causing spoilage of bakery products, Eurotium amstelodami, E. herbariorum, E. repens, E. rubrum, Aspergillus flavus, A. niger and Penicillium corylophilum. Methods and Results:The study applied 50 ll of pure essential oils in a sterilized filter paper, were carried out at pH 6 and at different water activity levels (0AE80-0AE90). First, a wheat flour based agar medium was used, where cinnamon leaf, clove, bay, lemongrass and thyme essential oils where found to totally inhibit all microorganisms tested. These five essential oils were then tested in sponge cake analogues, but the antifungal activity detected was much more limited. Conclusion: Five essential oils showed potential antifungal capacity against all species tested, over a wide range of water availability. Their activity, however, seems to be substrate-dependent. More research is needed to make them work in real bakery products, as in the preliminary study limited effectiveness was found. Significance and Impact of the Study: The potential of the cinnamon leaf, clove, bay, lemongrass and thyme essential oils against species belonging to Eurotium, Aspergillus and Penicillium genus has been demonstrated.