Improved methodology for the characterisation of transgenic Bt-11 maize cultivars using RP-HPLC profiles of albumin, globulin, prolamin, and glutelin protein fractions and chemometric analysis

A clear differentiation between Bt-11 transgenic and isogenic non-transgenic maize cultivars has successfully achieved analysing the perfusion and monolithic RP-HPLC profiles of the albumin, globulin, prolamin, and glutelin maize fractions together with a discriminant analysis. Significant differences between transgenic and isogenic non-transgenic cultivars were observed in the chromatograms obtained from any of the four protein fractions. The application of linear discriminant analysis to the area percentages corresponding to every peak detected in every protein fraction was successfully employed for the classification of transgenic Bt maize lines obtaining a global percentage of correct classification of 100%. For perfusion RP-HPLC, the variables with more discriminant power and prediction capability were the following peaks: peaks 1 and 3 for albumins, peak 2 for globulins, peaks 3 and 6 for prolamins, and peaks 7 and 8 for glutelins. In the case of monolithic RP-HPLC, the variables were peaks 2 and 3 for albumins, peak 5 for globulins, peaks 5, 6, and 7 of prolamins, and peak 10 for glutelins.