The presence of toxic or undesired substances in plant material can disturb homeostasis in both humans and animals (Massart et al. 2008; Shephard 2008b). These toxins enter the organism via the gastrointestinal tract, resulting in numerous adverse consequences (Cavret and Lecoeur 2006; Sergent et al. 2008). These substances include: (a) plant protective agents (Trucksess and Scott 2008); (b) industrial pollutants emitted to the environment (Crain et al. 2008; Shephard 2008a); (c) residues of veterinary medicines used in therapy; and (d) active substances naturally produced by plants, e.g., mycotoxins (Minervini and Dell'Aquilla 2008). The latter can cause millions of dollars of loss by unfavourably influencing human and animal health and can reduce the health qualities of plant products (Blandino et al. 2008). They have significant economic influence by diminishing livestock populations or causing problems in their growth and breeding (Egmond et al. 2007). According to legal regulations already in force concerning some mycotoxins (EU Commission Decree Nr 123/2005, 856/2005 and 1126/2007), their presence in edible goods results in national and international trade bans. Regarding feeding stuffs, only Commission Recommendation 576/2006 is in force in Europe. The above-mentioned mycotoxins are secondary metabolites of moulds mostly from the Penicillium, Aspergillus and Fusarium genera, which are very toxic and have mutagenic properties (aflatoxins, fumonizins, ochratoxin A, luteoscirin, toxin T-2), teratogenic properties (ochratoxin A, patulin, aflatoxin B1, toxin T-2) and/or estrogenic properties (zearalenone) (Jarvis and Miller 2005).