ABSTRACT
Ochratoxin A (OTA) is a polyketide secondary metabolite produced by many Aspergillus and Penicillium species (Abarca et al. 1994; Dalcero et al. 2002; Varga et al. 2003). It is a mycotoxin which results from a group of secondary metabolites produced by some fungal species and they can cause diseases or death when ingested by humans or animals (de Magalhães et al. 2011). This mycotoxin consists of a polyketide derived from a dihydroiso-coumarin moiety linked through the 12-carboxyl group to phenylalanine, via an amide linkage (Figure 11.1). It is a nephrotoxin which also displays hepatotoxic, teratogenic and immunosuppressive properties, and has been classified by The International Agency for Research on Cancer as a possible human carcinogen (group 2B; Kuiper-Goodman and Scott 1989; Petzinger and Ziegler 2000; Codex Alimentarius Commission 2013). Mycotoxin biosynthesis is related to environmental conditions such as temperature, humidity and rainfall during the cultivation, harvesting, post-harvesting and storage periods of agricultural products (de Magalhães et al. 2011). Ochratoxin A is mainly produced by Aspergillus carbonarius, A. niger and A. ochraceus in tropical zones, and by Penicillium verrucosum and P. nordicum in temperate zones (Pitt et al. 2000; Abrunhosa et al. 2001; O’Callaghan, Caddick, and Dobson 2003).
