Growth kinetics of cultures from single spores of Aspergillus flavus and Fusarium verticillioides on yellow dent corn meal.
A dilution protocol originally developed for the isolation of single bacterial cells was modified to suite the specificities of fungal growth. The modified protocol was used to study the growth kinetics of single spores of Aspergillus flavus and Fusarium verticillioides on yellow dent corn meal. Both a(w) and temperature significantly influenced the distributions of the colony growth rates and lag phases and the rate at which individual spores of both isolates completed the lag period. An interaction between a(w) and temperature was noted on the spread of the distributions of these growth parameters. The histograms of the single spore colony growth rates and lag phases generally became wider the more compromising the conditions for growth became, indicating a greater variation in growth ability at these conditions. The rate at which the single spores passed through the lag phases generally decreased with decrease in temperature and/or a(w), with an interaction again noted between these two factors on the rate. These results show the potential range and variability in growth of individual fungal spores at the lowest inoculum level possible.
Samapundo
Simbarashe
S
Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium.
Devlieghere
Frank
F
De Meulenaer
Bruno
B
Debevere
Johan
J
D001231:Aspergillus flavus / Q000502:physiology*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005670:Fusarium / Q000502:physiology*; D006801:Humans; D007700:Kinetics; D013045:Species Specificity; D013172:Spores, Fungal / Q000254:growth & development; D013696:Temperature; D014867:Water / Q000378:metabolism; D003313:Zea mays / Q000382:microbiology*
D014867:Water