Development of a real-time PCR assay targeting the sporulation gene, spo0A, for the enumeration of thermophilic bacilli in milk powder.
Thermophilic bacilli, such as Anoxybacillus, Geobacillus and Bacillus, are common contaminants growing within the processing lines of milk powder producing factories. These contaminants are used as indicator organisms for plant hygiene and specification limits based on their numbers have been implemented to ensure milk powder quality. In this study, we present a SYBR Green-based real-time PCR assay for the rapid detection and enumeration of these thermophilic bacilli in milk powder using the spo0A sporulation gene as quantification target. With this method the detection of thermophilic bacilli in milk powder can be accomplished within 1 h. The detection limit for reconstituted and inoculated milk was 80 vegetative cfu ml(-1) and 640 spores ml(-1), respectively.
Rueckert
Andreas
A
Thermophile Research Unit, Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton, New Zealand. andreas.rueckert@alumni.tu-berlin.de
Ronimus
Ron S
RS
Morgan
Hugh W
HW
D000595:Amino Acid Sequence; D000818:Animals; D001407:Bacillus / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D001483:Base Sequence; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004269:DNA, Bacterial / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005525:Food-Processing Industry / Q000592:standards; D008892:Milk / Q000382:microbiology* / Q000592:standards; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D016415:Sequence Alignment; D013045:Species Specificity; D013171:Spores, Bacterial / Q000254:growth & development / Q000302:isolation & purification; D013997:Time Factors
D004269:DNA, Bacterial