Simplex and Duplex Event-Specific Analytical Methods for Functional Biotech Maize

GMO Testing Laboratory, Experiment Research Institute of National Agricultural Products Quality Management Service, Seoul, South Korea.
Journal of Agricultural and Food Chemistry (Impact Factor: 2.91). 09/2009; 57(16):7178-85. DOI: 10.1021/jf901078d
Source: PubMed


Analytical methods are very important in the control of genetically modified organism (GMO) labeling systems or living modified organism (LMO) management for biotech crops. Event-specific primers and probes were developed for qualitative and quantitative analysis for biotech maize event 3272 and LY 038 on the basis of the 3' flanking regions, respectively. The qualitative primers confirmed the specificity by a single PCR product and sensitivity to 0.05% as a limit of detection (LOD). Simplex and duplex quantitative methods were also developed using TaqMan real-time PCR. One synthetic plasmid was constructed from two taxon-specific DNA sequences of maize and two event-specific 3' flanking DNA sequences of event 3272 and LY 038 as reference molecules. In-house validation of the quantitative methods was performed using six levels of mixing samples, from 0.1 to 10.0%. As a result, the biases from the true value and the relative deviations were all within the range of +/-30%. Limits of quantitation (LOQs) of the quantitative methods were all 0.1% for simplex real-time PCRs of event 3272 and LY 038 and 0.5% for duplex real-time PCR of LY 038. This study reports that event-specific analytical methods were applicable for qualitative and quantitative analysis for biotech maize event 3272 and LY 038.

1 Follower
7 Reads
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Here, we present a simple mathematical algorithm which leads to a so called performance factor based on the amplification efficiency and the correlation coefficient. It is a single normalized number capable to characterize main amplification characteristics of single or multiplex quantitative real-time PCR systems. To show the usefulness of this performance factor, it was applied to calculate a validation criterion of individual quantitative PCR runs, to compare different real-time PCR systems and to compare premixed DNA-polymerase kits from various producers. KeywordsMultiplex-Real-time quantitative PCR-Comparing-Performance
    European Food Research and Technology 09/2010; 231(5):727-732. DOI:10.1007/s00217-010-1330-7 · 1.56 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Transglutaminase is an enzyme that can be used to cross-link pieces of meat, fish or meat products. The resulting product gives the optical impression of an intact chunk of meat. The usage of transglutaminase as a food additive is permitted in some countries. However, its utilisation has to be declared to ensure transparency for consumers. This paper describes two orthogonal analytical methods suited for the detection of technological relevant transglutaminase concentrations (around 25 mg pure enzyme in 1 kg of product) in meat and meat products. The mass spectrometry-based approach relies on a previous digestion with Achromobacter lyticus protease and LC-MS/MS separation and detection. Sufficient selectivity was obtained by monitoring four different peptides. The orthogonal (complementary and independent), ELISA-based approach relies on two commercially available bacterial transglutaminase-specific antibodies, combined to a sandwich ELISA. The two methods were tested by analysing some 60 samples obtained from the market.
    Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment 06/2012; 29(9):1364-73. DOI:10.1080/19440049.2012.691557 · 1.80 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this chapter, contributors from the East Asian region (China, Korea, Taiwan and Japan) describe current issues related to the regulatory regimesfor GMO labelling and detection, and also discuss standardization of and research on detection methods. While mandatory labelling regimesare common in the East Asian region, the regimes differ in the thresholds for adventitious presence of GM material in non-GM products and in the items they cover. Consumer concern about imported GM crops is the major driver of the introduction of mandatory labelling regimes. However, commercial supply chains have gone through a number of changes and have adapted their practices to avoid labelling, by importing non-GM crops using identity-preservation. We describe the major impacts of GMO labelling regimes on selected, representative supply chains.As countries involved in the East Asian market become more and more dependent on each other, GMO detection and control also become important issues, and the region needs collaboration regarding method improvement and harmonization, information sharing, and research and development, among others.
    Genetically Modified and Non-Genetically Modified Food Supply Chains: Co-Existence and Traceability, 10/2012: pages 521-541; , ISBN: 9781444337785
Show more