Toxigenic Fusarium Species And Fumonisin B1 And B2 Associated With Freshly Harvested Sorghum And Maize Grains Produced In Karnataka, India

Fumonisins are toxic secondary metabolites produced by the species of Fusarium. Accurate detection of these toxins in
cereals is essential for a reliable evaluation of human exposure to these carcinogenic mycotoxins. In the present study,
maize and sorghum samples were randomly collected from different regions of Karnataka (India) used for the analysis
of fumonisin contamination. Preliminary mycological studies of samples confirmed the occurrence of mycotoxigenic
Fusarium species such as F. verticillioides (18 strains), F. proliferatum (2 strains) and F. anthophilum (2 strains). The
method used for the analysis of fumonisins was solvent extraction, C18 Sep-Pak reverse phase clean-up and orthophthalaldehyde
plus 2-mercaptoethanol derivatization followed by high-performance liquid chromatography with
fluorescence detector. The FB1 and FB2 concentration in maize patties inoculated with three different Fusarium species
ranged between 0.065 to 121.42 μg/g. Fumonisin concentrations in 13 of 15 natural maize samples were found to be
0.003-23.43 μg/g. similarly FB1 and FB2 concentrations in 07 of 13 natural sorghum samples were found to be 0.001
to 17.09 μg/g. The average yield of FB1 produced was much higher concentration to that of FB2 in all the samples
analyzed. Further, FB2 was always found in association with FB1 in all the samples analyzed by HPLC. This is first
report on the natural occurrence of fumonisins in cereals produced in Karnataka (India).