Polymerase chain reaction (PCR) detection is a commonly used method for species identification of meat products. However, this method is not suitable for the analysis of meat products containing multiple mixtures. This study aimed to test whether next-generation sequencing (NGS) technology could be used as a method for the certification of mixed meat products. In this study, five kinds of common meat (pigs, cattle, sheep, chickens, and ducks) were mixed as samples with different proportions. The primers designed from mitochondrial 16S rRNA and nuclear genome gene (growth hormone receptor, GHR), respectively, were used to detect these meats. The sequencing results of NGS were analyzed using a self-designed bioinformatics program. The fragments with similar sequences were classified and compared with the database to determine their species. The results showed that all five kinds of meat components could be correctly identified using these two primers. The meat composition could be detected as low as 0.5 in the mixed samples using the NGS technology targeting GHR gene fragments, which was superior to those targeting mitochondrial 16S rRNA. However, the quantitative detection of species in the mixture was not likely to be quite accurate due to the amplification bias of PCR amplification. These results showed that the NGS technology could be applied to identify meat species in mixtures.

Objectives: The purpose of this study was to determine the structural features and transferability of the multidrug-resistance (MDR) plasmid, and resistance phenotypes for the tested antimicrobials in foodborne Vibrio parahaemolyticus.Methods: Plasmids were isolated from a V. parahaemolyticus strain of seafood origin, then sequenced using the Illumina NovaSeq 6000 and PacBio Sequel II sequencing platforms to obtain the complete genome data. Characterization of the MDR plasmid pVP52-1, including determination of antimicrobial resistance genes (ARGs), plasmid incompatibility groups, and transferability, was carried out.Results: V. parahaemolyticus strain NJIFDCVp52 contained two circular chromosomes and two circular plasmids (pVP52-1 and pVP52-2). Plasmid typing indicated that pVP52-1 belonged to the incompatibility group IncA/C₂ and the sequence type pST3. pVP52-1 carried 12 different ARGs, an IS110-composite transposon consisting of aac(6′)-Ib-cr, qnrVC1, aac(6′)-Ib, dfrA14, and the IS26-mphA-IS6100 unit flanked by inverted sequences of IS5075 and IS4321. pVP52-2 carried no ARGs. A plasmid elimination assay showed that only pVP52-1 and its ARGs were lost, the loss of resistance to several antimicrobials, causing a change from the ampicillin-ampicillin/sulbactam-cefazolin-cefoxitin-ceftazidime-cefotaxime-imipenem-trimethoprim/sulfamethoxazole resistance pattern to the ampicillin resistance pattern. In accordance, a conjugation transfer assay showed that only pVP52-1 and its ARGs were horizontally transferred, leading to increased antimicrobial resistance in Escherichia coli strain EC600, causing a change from the ampicillin-nalidixic acid resistance pattern to the ampicillin-ampicillin/sulbactam-cefazolin-cefoxitin-ceftazidime-cefotaxime-imipenem-nalidixic acid-chloramphenicol-tetracycline-trimethoprim/sulfamethoxazole-azithromycin resistance pattern. Further transferability experiments revealed that pVP52-1 could be transferred to other enterobacterial strains of E. coli and Salmonella.Discussion: This study emphasizes the urgent need for continued surveillance of resistance plasmids and changes in antimicrobial resistance profiles among the V. parahaemolyticus population.

The rapid detection of pathogenic bacteria is important for the global public health field. Existing detection technologies are generally limited by log efficiency, high costs, and susceptibility to contamination. Advanced detection methods, such as surface plasmon resonance (SPR), have been proposed to break these limitations, with the advantages of fast detection speed and high sensitivity. SPR operates on the principle of attenuated total internal reflection at a metal–dielectric interface. This technique exploits the resonant absorption of incident photons by surface plasmons, facilitating the detection of tiny variations in the local refractive index by tracking the resonance condition change. This review provides a comprehensive overview of the development in the detection of foodborne pathogens using SPR technology, including a detailed discussion of the working principles of SPR, related instrumentation, and various detection methods. Specifically, this review focuses on a discussion of different SPR detection methods in terms of assembly processes, detection specificity, sensitivity, and detection limits in SPR biosensors, aiming to provide the readers with a fundamental knowledge of SPR.