Impact on growth and aflatoxin B1 accumulation by Kluyveromyces isolates at different water activity conditions

Abstract

This study showed the impact on germination, mycelial growth and aflatoxin B1 accumulation when interacting Aspergillus aflatoxigenic strains with Kluyveromyces isolates and the effect of water activity on this relationship. Isolates Y14 and Y16 reduced the percentage of germination of all Aspergillus strains and decrease germ tube elongation rate at majority of water activity assayed. Similarly they produced an increase of germination lag phase and lag phase of growth beside decreased growth rate of all Aspergillus strains. At water activities 0.994, 0.982, 0.955 and 0.937, no aflatoxins were produced in paired cultures with isolates Y25, Y22, Y16, and Y14, and Kluyveromyces isolates Y14 and Y16 impact both growth and aflatoxin accumulation at wide range of water activity.