A real-time polymerase chain reaction-based method for rapid and specific detection of spoilage Alicyclobacillus spp. in apple juice.
OBJECTIVE
To develop a real-time PCR-based rapid detection method for spoilage Alicyclobacillus spp. in juice products.


RESULTS
The squalene-hopene cyclase-encoding gene was targeted for primer-and-probe development. Gene fragments from representative strains were cloned, and PCR primers and probe were designed by DNA sequence comparison. Selected bacteria were examined for cross-reactivity by the new method. Cells were serially diluted in apple juice and saline, and examined by the new method to establish detection sensitivity. Using the newly developed Taqman real-time PCR-based method, strains of Alicyclobacillus acidocaldarius and A. acidoterrestris were detected without cross reactivity with other common food-borne micro-organisms. Detection of <10 cells per PCR reaction from juice samples was accomplished within 3-5 h.


CONCLUSIONS
This is the first reported real-time PCR-based detection method for Alicyclobacillus spp. and its application in juice products is demonstrated.


CONCLUSIONS
As a favourable alternative for the laborious and time-consuming culture- or biochemical characterization-based techniques, the system has great potential for industrial applications from raw material screening to final product quality control.
Luo
H
H
Department of Food Science and Technology, The Ohio State University, Columbus, OH 43210, USA.
Yousef
A E
AE
Wang
H H
HH
D001407:Bacillus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D001628:Beverages / Q000382:microbiology*; D016937:Gram-Positive Endospore-Forming Rods / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D027845:Malus / Q000382:microbiology*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D013997:Time Factors