spores in Polish honey samples.

The aim of this study was an examination of 240 multifloral honey samples collected from Polish apiaries to determine occurrence. Honey was collected from apiaries directly after the extraction process. Samples were inoculated by using the dilution and centrifugation method. Suspected isolates were examined by using mouse bioassay, polymerase chain reaction (PCR), and real-time PCR methods. type A and B strains were detected in 5 of 240 examined honey samples (2.1%). Bacterial strains were also detected that were phenotypically similar to but that did not exhibit the ability to produce botulinum toxins and did not show the presence of the botulinum cluster ( and genes) or expression of the gene. The methods used in the examination, especially the expression analysis of gene, enabled specific analysis of suspected strains and could be used routinely in environmental isolate analyses of occurrence.