Quantitative Determination of Roundup Ready soybean (Glycine max) Extracted from Highly Processed Flour

Roundup Ready soybean powder was subjected to various degrees of DNA fragmentation in order to assess the accuracy of a real-time PCR on processed food. Certified Reference Material (CRM) containing 10 g/kg of Roundup Ready soybean (ERM-BF410d) prepared by a dry-mixing processing method was exposed to water at two temperatures using three different mixing devices or to a baking temperature (250 °C) for 30 min. The amount of extracted DNA from the different samples was quantified by fluorometry. The degree of fragmentation of the extracted DNA was characterised by gel and capillary electrophoresis and the percentage of genetically modified soybean was determined by a double quantitative real-time PCR method. Measurements of the event GTS 40-3-2 (RUR) was possible in all the treated materials since small amplicons were amplified. Correct RUR percentages could be measured on intact powders showing no or little DNA fragmentation. However for samples presenting a high level of DNA degradation, the accuracy of the measurement was then found dependent of the DNA extraction method used. Genomic DNA isolated using silica resin generated a statistically significant overestimation of the measured GM percentage.

CORBISIER Philippe;  TRAPMANN Stefanie;  GANCBERG David;  HANNES Elisabeth;  VAN IWAARDEN Pierre;  BERBEN Gilbert;  SCHIMMEL Heinz;  EMONS Hendrik; 

2006-03-31

SPRINGER

JRC30972

https://publications.jrc.ec.europa.eu/repository/handle/JRC30972,   

10.1007/s00216-005-0013-x,