Construction and application of loop-mediated isothermal amplification method for detection of brazil nut as a food allergen

According to the Bertholletia excels 2S albumin gene sequences, this article designed and screened sets of loop-mediated isothermal amplification (LAMP) primers using a design software named Primer Explorer Version 4, then established the relevant LAMP method for detection of Brazil nut as a food allergen, whose results could be measured by real-time fluorescence or using a fluorescent dyes in the end reaction. The specificity of this method was evaluated by detection of 17 nut samples include macadamia nut, pistachio, pecan, and so on. The sensitivity was tested using DNA gradient dilutions, and the stability was assessed with detection of 0.5%, 1%, 1.5% gradient dilutions of Brazil nut DNA for 20 times. It was indicated that this method had satisfied specificity, sensitivity and stability in the identification of Brazil nut in foods with a LOD of 0.5%. In addition, the detection of 7 market food samples using this method showed the 100% consistency to the labeled information of allergen ingredients with 0% false positive and negative rates.