Loop-mediated isothermal amplification-based rapid detection for Shigella dysenteriae in food samples

Abstract:

[Objective] To study and optimize loop-mediated isothermal amplification method for rapid detection of Shigella that can cause infectious diarrhea in conventional food consumption. [Methods] High conservative and specific target gene sequence of Shigella gene was aligned and obtained from NCBI (National Center for Biotechnology Information) database. Three pairs of corresponding LAMP primers were designed, synthesized and used to establish the LAMP-based visualized detection method. The detection result of practical samples by using LAMP-based detection method was compared with those obtained by conventional methods for statistical analysis. [Results] All 5 strains of Shigella standard strain samples were detected positive and 11 strains of non-Shigella standard samples were detected negative, which showed no cross reaction. The minimum test limit is 16 CFU per test or 3.2×102 CFU/mL, and by comparison, the sensitivity of LAMP detection was 10 times higher than PCR detection. All 161 sets of samples were detected by LAMP, and the results showed high consistency with conventional detection method. [Conclusion] The LAMP-based detection method is featured with advantages in convenience, rapidity and high reliability, which makes it applicable to meet the requirements of rapid detection for Shigella in different types of food samples.