An enhanced visual detection assay for Listeria monocytogenes in food based on isothermal amplified peroxidase-mimicking catalytic beacon. (April 2022)

• Record Type: Journal Article
• Authors: Wu, Xianyong; Chen, Qiming; Yang, Cuiyun; Ning, Qiqi; Liu, Zhanmin
• Is Part Of: Food control. Volume 134(2022)
• Publication Date: 2022-04
• Subjects: G-quadruplex DNAzyme -- Polymerase spiral reaction -- Listeria monocytogenes -- Visual detection; Food -- Quality -- Periodicals; Food -- Analysis -- Periodicals; Food handling -- Periodicals; Food industry and trade -- Quality control -- Periodicals; Aliments -- Industrie et commerce -- Qualité -- Contrôle -- Périodiques; Aliments -- Qualité -- Périodiques; Aliments -- Analyse -- Périodiques; Hygiène alimentaire -- Périodiques; Food -- Analysis; Food handling; Food -- Quality; Periodicals; Electronic journals; 664.07
• DOI: 10.1016/j.foodcont.2021.108721
• Languages: English
• ISSNs: 0956-7135

Abstract

Abstract: Listeria monocytogenes is a kind of foodborne pathogen, which can cause meningitis, septicemia, gastroenteritis, and abortion with a fatality rate of up to 30%. Rapid, sensitive, and convenient detection of L. monocytogenes in food is an important strategy for controlling contamination and infection. In this study, an enhanced visual detection assay for L. monocytogenes based on an isothermal amplified peroxidase-mimicking catalytic beacon was developed. When L. monocytogenes existed, G-quadruplex sequences were amplified together with targeted gene sequence by polymerase spiral reaction (PSR). G-quadruplex adequately formed DNAzyme with hemin to have an enhanced peroxidase-like bioactivity with help of Nb. Bbv CI nicking endonuclease, which could display significant colorimetric signals for indicating positive results qualitatively. The sensitivity test results determined that our assay enabled the quantitative detection of L. monocytogenes ranging from 10 to 10 5 CFU mL −1, as well as had a detection limit of 3.1 CFU mL −1, which was lower than previous visual detection assays for L. monocytogenes . Besides, it was notable that this assay could detect L. monocytogenes with the concentration of 2.0 lg CFU/g in artificially contaminated pork samples within about 4 h, with the advantages of high sensitivity, simple operation, and good visual signal output. We believed the improved visual detection assay based on isothermal amplified peroxidase-mimicking catalytic beacon showed great potential for food safety analysis. Highlights: PCR amplifier and labeled primer were not required. The visual effect was improved by nicking endonuclease and additional K + . The detection assay in this study could be used in the quantitative analysis. The detection of L. monocytogenes in real samples could be finished in less than 4 h.