, Volume 116, Issue 2, pp 71–75 | Cite as

Transformation of sterigmatocystin and O-methylsterigmatocystin by aflatoxigenic and nonaflatoxigenic field isolates of the Aspergillus flavus group

  • María J. Pro
  • Miguel A. Moreno
  • Guillermo Suárez


Transformation of sterigmatocystin and O-methylsterigmatocystin (two metabolic aflatoxin precursors) to aflatoxins by aflatoxigenic and nonaflatoxigenic field isolates of Aspergillus flavus was studied. The 24 nonaflatoxigenic isolates investigated failed to transform both precursors. Among the 8 aflatoxin-producing isolates used, 7 transformed both precursors whereas the remaining failed to transform both. According to these results, the usefulness of the measurement of enzymatic activities related to aflatoxin production in understanding the true status of conflictive field isolates is discussed.

Key words

Transformation sterigmatocystin O-methylsterigmatocistin A. flavus field isolates 







aflatoxin B1


aflatoxin B2


aflatoxin G1


aflatoxin G2


growth medium of Adye and Mateles


replacement medium of Adye and Mateles


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Copyright information

© Kluwer Academic Publishers 1991

Authors and Affiliations

  • María J. Pro
    • 1
  • Miguel A. Moreno
    • 1
  • Guillermo Suárez
    • 1
  1. 1.Departamento de Patología Animal I (Sanidad Animal), Facultad de VeterinariaUniversidad ComplutenseMadridSpain

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