Effect of water activity and temperature on growth and the relationship between fumonisin production and the radial growth of Fusarium verticillioides and Fusarium proliferatum on corn

• Published in: Journal of food protection 2005-05, Vol.68 (5), p.1054-1059
• Main Authors: Samapundo, S, Devliehgere, F, Meulenaer, B. de, Debevere, J
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; biosynthesis; Cereal and baking product industries; Consumer Product Safety; corn; food contamination; Food Contamination - analysis; Food industries; food pathogens; fumonisins; Fumonisins - analysis; Fundamental and applied biological sciences. Psychology; Fusarium - growth & development; Fusarium - metabolism; Fusarium proliferatum; Fusarium verticillioides; Gibberella fujikuroi; Humans; Linear Models; microbial growth; molds (fungi); secondary metabolites; sporulation; Temperature; toxigenic strains; Water - metabolism; water activity; water content; Zea mays; Zea mays - microbiology
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X-68.5.1054

The two major fumonisin-producing Fusarium species are Fusarium verticillioides and Fusarium proliferatum. The growth and fumonisin production of these two isolates on corn was studied at water activities (a(w)) between 0.860 and 0.975 and at temperatures between 15 and 30 degrees C. Growth rates (g, mm/day) were obtained by linear regression during the linear phase of growth. In general, growth rates for both isolates increased significantly (P < 0.05) with increases in a(w) and temperature. Both fumonisin production and radial growth (mycelial development) for both isolates increased with a(w) at all temperatures investigated, but the effect of temperature on this relationship was not obvious. The effect of temperature on fumonisin production at high a(w) values optimal for growth was only marginal, whereas at lower a(w) values the effect of temperature was more pronounced, with more fumonisin production occurring at temperatures not optimal for growth. The optimum temperature for fumonisin production was between 15 and 25 degrees C. For F. proliferatum, the optimum temperature for growth at all a(w) values, 30 degrees C, resulted in the poorest fumonisin production. For both isolates, the slowest initial rate of fumonisin production was at 15 degrees C, the temperature at which the slowest growth rates were obtained.