%0 Journal Article
%A García García, Aina
%A Madrid García, Raquel
%A Sohrabi, Hamidrezah
%A Cruz, Silvia de la
%A García Lacarra, Teresa
%A Martín De Santos, María Del Rosario
%A González Alonso, María Isabel
%T A sensitive and specific real-time PCR targeting DNA from wheat, barley and rye to track gluten contamination in marketed foods
%D 2019
%@ 0023-6438
%U https://hdl.handle.net/20.500.14352/94204
%X This work reports a real-time PCR assay to specifically detect the presence of DNA from the main gluten-containing cereals wheat, barley and rye (WBR) in foodstuffs. The WBR real-time PCR uses two specific primers and a Taqman probe for amplification of a 118 bp DNA fragment common to the three target cereals on the ribosomal internal transcribed spacer (ITS) region. In-house validation of the method was performed employing three binary arrays containing different concentrations (100 000–10 mg/kg) of a wheat/barley/rye mixture in maize flour: untreated, soft heat-treated at 160 °C/13 min and intense heat-treated at 200 °C/20 min. Results showed optimal PCR amplification efficiency, reproducibility and sensitivity with an overall limit of detection of 10–50 mg/kg of the target cereals, theoretically equating to approximately 1–5 mg/kg of gluten. Applicability of the assay was further assessed through a market analysis of 220 food products by the real-time PCR assay and the official R5-based ELISA. Comparative results highlighted the ability of the proposed methodology as a highly sensitive and robust procedure to detect the presence of potentially harmful concentrations of undeclared gluten-containing cereals in some of the tested samples, supporting results of the immunological assays currently used for gluten determination in foods.
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