DETECTION OF BACILLUS CEREUS CONTAINING VOITOXININ FOOD BY LOOP-MEDIATED ISOTHERMALAMPLIFICATION METHOD

摘要

Bacillus cereus strains containing voitoxin cereulide are pathogenic bacteria. Thecereulide is produced by B. cereus strains containing plasmid pCER270. To establisha specific loop-mediated isothermal amplification (LAMP) method detectingpathogenic B. cereus, LAMP primer sets were designed based on 16SrDNA andpCER270 plasmid cesA sequence.TheLAMPreaction was carried out under optimalconditionswith 2 mMofMg2+ at 65C for 1 h. Specificity of LAMPprimerswere validatedby assaying 19 B. cereus strains with and without pCER270 plasmid and 42non-B. cereus species. Detection limits of the LAMP assay were 1 cfu/mL of B. cereuswithout pCER270 plasmid and 11 cfu/mL of pathogenic B. cereus with pCER270plasmid. Furthermore, liquid milk sampleswere detected by the LAMP method. Theresults showed that LAMP method is a reliable method used for rapid detection of B.cereus and its pathogenic strains of milk and other food stuff.