Original Article
  

Molecular Detection of the Major Peanut Allergen Ara h 1 in Food Products Using a Duplex Polymerase Chain Reaction Assay

Abstract

Peanut allergy is a major global health concern, and undeclared peanut residues in processed foods pose serious risks to sensitized individuals. Reliable analytical methods are essential for accurate labeling and consumer protection, particularly because high-heat processing can cause protein denaturation and DNA fragmentation.
This study assessed the applicability and analytical reliability of a short-amplicon duplex quantitative polymerase chain reaction (qPCR) system targeting the Ara h 1 gene across diverse peanut genotypes, thermally processed samples, and commercial food matrices. Genomic DNA was extracted from raw peanuts representing 11 varieties, roasted and autoclaved samples, and commercial foods using a modified cetyltrimethylammonium bromide (CTAB)-based protocol. The duplex qPCR assay targeted the Ara h 1 gene and incorporated 18S rRNA as an internal amplification control on the Rotor-Gene Q platform.
The assay detected all peanut varieties consistently, with a limit of detection (LOD) of 100 pg of DNA. The short amplicon (<150 bp) enabled reliable detection even after severe thermal processing (autoclaving at 121°C for 15 min). Validation across commercial food products demonstrated that the 18S rRNA internal control effectively prevented false-negative results in inhibitor-rich matrices, such as chocolate and cocoa-based foods.
These findings confirm that Ara h 1 is a stable and robust molecular target for detecting trace peanut residues in both raw and processed food products, supporting regulatory compliance and food safety for allergic consumers.

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Keywords
Allergens Arachis DNA Food analysis Food safety; Molecular diagnostic techniques Plant proteins Plant Real-time polymerase chain reaction
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How to Cite
1.
Mohammad-rezaei M, Noroozbeygi M, gisouei A, khazeni fard S, Khoshmirsafa M, Assarehzadegan M-A. Molecular Detection of the Major Peanut Allergen Ara h 1 in Food Products Using a Duplex Polymerase Chain Reaction Assay. Iran J Allergy Asthma Immunol. 2026;:1-14.