Abstract

  Salmonella is one of the most frequently isolated foodborne pathogens. The genus members are recognized as a major cause of enteric fever and gastroenteritis. It was aiming at detection of Salmonella in some food samples (Row beef, row chicken, um fit fit, salad rocket and cucumber) collected from different markets in Khartoum state, Sudan. Ten food samples were collected from markets with poor hygiene and others with almost high hygiene. The conventional culture method for detection of Salmonella was used as well as PCR technique. DNA was extracted from Salmonella colonies and from the pre-enrichment culture. PCR was conducted using primers pair which amplify a 389-bp fragment within the conserved inv A gene sequence of salmonella spp. The results showed that 80% of food samples were positive when tested with conventional method. All meat samples tested (beef, chicken and um fit fit) were positive, while 50 % of the vegetables were positive (one cucumber and one rocket). However, the ten food samples (100%) were showed positive reaction in the biochemical test. the purity of the DNA was between 1.28 - 2.05, and the concentration ranged from 1.21 to 22.7 ng/µl. From the PCR conducted from Salmonella colonies, nine samples (90%) were positive by PCR, 50% of beef meat while other samples were all positive (100%). However, all samples were negative in PCR when the DNA extracted from the pre-enrichment culture.

Keywords: Salmonella; Food Samples; DNA-Based Methods

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Citation

Citation: Elhadi A I Elkhalil., et al. “Detection of Salmonella in Some Food Samples Using Culture and DNA-Based Methods". Acta Scientific Microbiology 3.4 (2020): 40-43.

Copyright

Copyright: © 2020 Elhadi A I Elkhalil., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.