Tracing two Roundup Ready (TM) soybean lines (GTS 40-3-2 and MON89788) in foods commercialised in Portugal

摘要

Soybean (Glycine max L.) is the most important genetically modified (GM) crop, from which the glyphosate tolerant soybean, also known as Roundup Ready (RR), is one of the most representative. The present work intends to assess the presence of two RR soybean lines, namely GTS 40-3-2 and MON89788, in a wide range of processed foods commercialised in Portugal. For this purpose, two quantitative real-time PCR approaches were proposed using available and newly designed primers. The results showed that, from 90 food samples, 73 confirmed the presence of soybean, while 15 others suggest their incompliance with labelled soybean. RR soybean was detected in 9 samples, from which 5 were identified as being the GTS-40-3-2 event, 3 the MON89788 event and one contained both events. The developed real-time PCR methods were successfully validated through the participation in an interlaboratory proficiency program and applied to processed foods. The estimated RR soybean contents of 8 samples ranged between 0.01 and 0.39%, but the sample containing both events accounted for 23.9% of GM ingredients. Such high level above the threshold for labelling regulations suggests the need of more strict control of GMO in foods. (C) 2016 Elsevier Ltd. All rights reserved.