AUTOMATED BACTERIAL DNA ISOLATION FROM FOOD AND FEED SAMPLES – A BIOPREPAREDNESS DESIGN

摘要

ABSTRACT A high‐throughput biosafety level 3 suitable method is necessary for rapid discovery of unknown pathogens in complex matrices from the food chain. In this paper, three automated bacterial DNA extraction methods for real‐time polymerase chain reaction (PCR) detection were evaluated. The systems compared were the Magnatrix (NorDiag, Oslo, Norway) and the EZ1 (Qiagen, Hilden, Germany), both based on purification with magnetic beads, and the ABI Prism™ 6100 Nucleic Acid PrepStation (Applied Biosystems, Foster City, CA), which is based on silica gel filtration. In the comparison, the detection of bacterial DNA from food and feed seeded with one Gram‐positive and one Gram‐negative bacterial species was compared. A wider range of matrices were successfully processed using the magnetic bead‐based DNA extraction robots compared with the silica gel filtration‐based robot. The limit of detection was 10 2 –10 3 cfu/g matrix of both bacteria in powdered milk, minced meat, whole wheat and soypass using the EZ1 extraction robot. PRACTICAL APPLICATIONS A rapid, wide‐range method to discover unknown dangerous pathogens in complex matrices from the food chain is crucial to minimize the effects in the society of extraordinary events. These events are defined as accidents or unexpected disease outbreaks and deliberate spread of highly pathogenic bacteria. Gaining knowledge of the advantages and disadvantages of extraction methods from complex matrices is important in the development of fast and reliable detection methods.