Molecular Strategies for Reducing Aflatoxin Levels in Crops before Harvest

  • Thomas E. Cleveland
  • Deepak Bhatnagar


Aflatoxins, produced by the filamentous fungi Aspergillus flavus and A. parasiticus, are potent toxins and carcinogens that contaminate food and feed worldwide (Jelinek, Pohland, and Wood 1989). Aflatoxin B1 is the most toxic of the aflatoxin family of compounds (see Fig. 9–1) and is usually the predominant compound; however, other “naturally produced” aflatoxins (B2, Gl, and G2) are also toxic and contaminate food and feed. The aflatoxin family of compounds can form “adducts” with animal and human DNA (Hsu et al. 1991; Bressac et al. 1991) and can cause primary liver cancer in certain animal systems (Groopman and Sabbioni 1991; Wogan 1991). In human systems, the carcinogenicity of aflatoxins is less clear (Campbell et al. 1990), but certain associations between aflatoxin intake by human populations and primary liver cancer have been reported (Groopman and Sabbioni 1991; Yeh et al. 1989). With possible implications to human and animal health worldwide, intense efforts are underway to remove these compounds from animal and human food chains.


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© Van Nostrand Reinhold 1992

Authors and Affiliations

  • Thomas E. Cleveland
  • Deepak Bhatnagar

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