Establishment and Evaluation of a Loop-Mediated Isothermal Amplification Assay for Rapid Detection of Pseudomonas fluorescens in Raw Milk

Yushan Bu; Wenjun Qiao; Zhengyuan Zhai; Tongjie Liu; Pimin Gong; Lanwei Zhang; Yanling Hao; Huaxi Yi

doi:10.3389/fmicb.2021.810511

Establishment and Evaluation of a Loop-Mediated Isothermal Amplification Assay for Rapid Detection of Pseudomonas fluorescens in Raw Milk

Front Microbiol. 2022 Jan 6:12:810511. doi: 10.3389/fmicb.2021.810511. eCollection 2021.

Authors

Yushan Bu¹, Wenjun Qiao¹, Zhengyuan Zhai², Tongjie Liu¹, Pimin Gong¹, Lanwei Zhang¹, Yanling Hao^{2

3}, Huaxi Yi¹

Affiliations

¹ College of Food Science and Engineering, Ocean University of China, Qingdao, China.
² Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Municipality, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
³ College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.

Abstract

Raw milk is susceptible to microbial contamination during transportation and storage. Pseudomonas fluorescens producing heat-resistant enzymes have become the most common and harmful psychrophilic microorganisms in the cold chain logistics of raw milk. To rapidly detect P. fluorescens in raw milk, the protease gene aprX was selected as a detection target to construct a set of primers with strong specificity, and a loop-mediated isothermal amplification (LAMP) assay was established. The detection thresholds of the LAMP assay for pure cultured P. fluorescens and pasteurized milk were 2.57 × 10² and 3 × 10² CFU/mL, respectively. It had the advantages over conventional method of low detection threshold, strong specificity, rapid detection, and simple operation. This LAMP assay can be used for online monitoring and on-site detection of P. fluorescens in raw milk to guarantee the quality and safety of dairy products.

Keywords: LAMP; P. fluorescens; detection; rapid; raw milk.