Transgenic versus conventional corn: fate of fumonisins during industrial dry milling

摘要

The aim of this study was to compare the fate of fumonisins in transgenic and non-transgenic com during industrial dry milling. For this purpose, whole com samples and their fractions (germ, pericarp, endosperm, com meal, and grits) were collected from one of the major Brazilian milling plants, totaling 480 samples. There was no significant difference (p > 0.05) between mean fiimonisin (FBt + FB2) levels in transgenic (1130 ug/kg) and non-transgenic (920 u-g/kg) whole com. However, in non-transgenicgerm, endosperm and corn meal fraction fumonisin levels were higher (2940 ug/kg, 250 ug/kg and 190 ug/kg, respectively) than in transgenic fractions (2180 ug/kg, 130 u-g/kg and 85.0 ug/kg, respectively). Furthermore, the highest percentages of fumonisinswere distributed in the germ, corresponding to about 87 and 76% of the total fumonisins present in the whole com from non-transgenic and transgenic hybrids, respectively. Concerning the endosperm from non-transgenic and transgenic com, approximately, 23% and 13% of the total fumonisins were retained after the dry milling. Further processing in com meal (300 to 420 um particle size) and grits (590 to 1190 um) decreased the percentages of remaining fumonisins to 4% and 2% (transgenic) and 10% and 3% (non-transgenic com), respectively. These results suggested that fumonisin concentration was higher in outer and inner non-transgenic fractions when compared to transgenic ones and that the fate of fumonisins during the industrial dry milling could be affected by the transgenic status. However, it was not possible to conclude that the difference was exclusively due to this variable.