Capillary Electrophoresis Time-of-Flight Mass Spectrometry for Comparative Metabolomics of Transgenic versus Conventional Maize

Abstract

In this work, capillary electrophoresis time-of-flight mass spectrometry (CE-TOF-MS) is proposed to identify and quantify the main metabolites in three lines of genetically modified (GM) maize and their corresponding nontransgenic parental lines grown under identical conditions. The shotgun-like approach for metabolomics developed in this work includes optimization of metabolite extraction from GM and non-GM maize, separation by CE, online electrospray-TOF-MS analysis, and data evaluation. A large number of extraction procedures and background electrolytes are tested in order to obtain a highly reproducible and informative metabolomic profile. Thus, using this approach, significant differences were systematically observed between the detected amounts of some metabolites in conventional varieties (Aristis, Tietar, and PR33P66 maize) compared with their corresponding transgenic lines (Aristis Bt, Tietar Bt, and PR33P66 Bt maize). Results point to some of these metabolites as possible biomarkers of transgenic Bt maize, although a larger number of samples needs to be analyzed in order to validate this point. It is concluded that metabolomics procedures based on CE-TOF-MS can open new perspectives in the study of transgenic organisms in order to corroborate (or not) their substantial equivalence with their conventional counterparts.

An optimized procedure for metabonomic analysis of rat liver tissue using gas chromatography/time-of-flight mass spectrometry

“…The measurement of metabolome variations in response to stimuli has been widely used in modern pharmaceutical and biomedical research [1,2]. The main analytical methods employed for metabonomic studies are based on informationrich spectroscopic techniques, such as nuclear magnetic resonance (NMR) spectrometry and mass spectrometry (MS), which is usually coupled with gas chromatography (GC/MS), liquid chromatography (LC/MS) or capillary electrophoresis (CE/MS) [3][4][5]. Metabonomic studies generate complex multivariate data that requires chemometrics for interpretation [6].…”

Foodomics and Food Safety: Where We Are

“…This kind of information is also very important for the determination of metabolites in genetically modifi ed food (138,198). However, with corresponding sample preparations and in--front separation by liquid chromatography or capillary electrophoresis, FT-ICR MS (199), MALDI-TOF MS (200) and other mass spectrometry techniques (201) have been proven to be equally effi cient analytical tools for these kinds of tests.…”

Food Analysis: Present, Future, and Foodomics

“…These tools have already been demonstrated to be very useful for getting a deeper understanding of molecular details of foods and food related matrices [171][172][173] including the analysis of GM foods. In this later case, the use of omics approaches able to provide useful fingerprints of GM foods (e.g., for GM detection, composition monitoring, traceability, study of unintended modifications, and labelling issues) has already been recommended by the European Food Safety Authority [33,[174][175][176]. In this context, metabolomics (via GC-MS, LC-MS, CE-MS, or NMR) has potential to add significant value to crop and food science, raw material quality and safety, food storage, shelf life, and postharvest processing [177].…”