Detection of pathogenic Escherichia coli such as E. coli O157 and ETEC has been known as an
extremely important indication for their prevalence in many types of samples. The quality and quantity of DNA
and the sensitivity of DNA detection may vary upon different extraction techniques and directly affect the
results of sample analysis. In this study we compared five chromosomal DNA extraction methods using
conventional method; the phenol/chloroform extraction, and other four more rapid ones: the ChargeSwitch gDNA
Mini Kit, ChelexTM 100, InstaGeneTM Matrix and InstaGeneTM Matrix+lysozyme. The results of DNA extraction
were evaluated by agarose gel electrophoresis, optical density determination and amplification of specific
DNA fragment. The phenol/chloroform extraction and InstaGeneTM Matrix methods gave the DNA that
provided higher sensitivity of pathogenic E. coli detection by PCR at the detection limit of