Biological control aflatoxins

Other preharvest techniques include the development of more resistant crops (e.g., Becker, 1999 Guo et al., 1998), and biological control with atoxigenic A. flavus strains (Cotty, 1990 Dorner et al., 1998). Atoxigenic A. jiavus competed successfully with a toxic isolate when they were grown in mixed culture, obtaining a reduction of the aflatoxin content by 82 to 100%. This is a worthwhile approach for control, however possible side effects caused by a preemptive application of A. jiavus in the environment must be studied to determine potential risks to human and animal health. 

Experience in our laboratory suggests a combined approach utilizing both host defense augmentation and biological control will be necessary to complement existing conventional methods in the eventual elimination of aflatoxin from the food and feed supply. 

Mishra HN and Das CA (2003) A review on biological control and metabolism of aflatoxin. Critical Reviews in Food Science and Nutrition 43(3) 245-264. 

Hua, S.-S.T. (2004) Field assessment of an effective yeast strain to control aflatoxin-producing fungus, Aspergillus flavus. In Proceedings addendum, California conference on biological control IV. 13-15 July, Berkeley, CA, USA, pp. 154-157. 

Heathcote JG, Hibbert JR Biochemical effects, structure activity relationships in Goldblatt LA (ed) Aflatoxin Chemical and Biological Aspects. Amsterdam, Elsevier, 1978, pp 112-130. Dickens JW Aflatoxin control programme for peanuts. J Am Oil Chem Soc 1977 54 225A-228A. Goldblatt LA, Dollear FG Review of prevention, elimination and detoxification of aflatoxins. Pure Appl Chem 1977 49 1759-1764. 

The potential for unusual health effects of chemical mixtures due to the interaction of chemicals or their metabolites (e.g., metabolites of trichloroethylene and benzene) in or with the biosystem constitutes a real issue in the public health arena. However, toxicity testing to predict effects on humans has traditionally studied one chemical at a time for various reasons convenient to handle, physiochemical properties readily defined, dosage could easily be controlled, biologic fate could easily be measured, and relevant data were often available from human occupational exposures. Chemicals are known to cause disease for example, arsenic and skin cancer, asbestos and lung cancer, lead and decrements of IQ, and hepatitis B predisposes to aflatoxin-induced liver cancer but the link between the extent of human exposure to even well-defined chemical mixtures and disease formation remains relatively unexplored, but of paramount importance to public health. 

The analysis of food contaminants, in particular any toxic or biologically active residue, is important for public health or quality control reasons.19 Examples are mycotoxins (aflatoxins) and pesticide and drug residues. Sample preparation is typically elaborate and might involve deproteinization, solvent extraction, and clean-up via solid-phase extraction (SPE).The use of highly sensitive and specific LC/MS/MS is increasing and has simplified some of the sample preparation procedures. 

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