Establishment and preliminary application of oligonucleotide microarray assay for detection of food-borne toxigenic microorganisms

Rapid, high-throughput and accurate detection and identification of food-borne toxigenic microorganisms is crucial for food safety nowadays. An oligonucleotide microarray was designed and established and was applied to detect common food-borne toxigenic microorganisms in this study. PCR amplification of marker genes and 16S rRNA gene of 14 toxigenic bacteria and fungi using specific primers and oligo probes residing in these genes were employed and designed to fabricate the microarray. Optimization of hybridization conditions was implemented. The optimal conditions for hybridization were 51 °C for 30 min. Furthermore, the ratio of biotin labeled to unlabeled primer for PCR amplification was also optimized to enhance specific hybridization of the microarray. Specificity, sensitivity (710 CFU/mL), and reproductivity assessment confirmed the practicability of the microarray. Finally, this microarray was successfully applied to detect 6 common toxigenic microorganisms from 328 food samples. The established microarray may provide potential for rapid detection and identification of toxigenic microorganisms from foods.