Molecular Detection of Virulence Genes in Escherichia coli and Salmonella enterica Isolated from Minimally Processed Foods Sold within Kaduna Metropolis

  • *Haroun, A. A., Hafsat, A., Kabir, K. and Denwe, D.

  • UJMR 2022, 7(1), Pp 75 - 81, DOI:  10.47430/ujmr.2271.012


This study was aimed at detecting virulence genes in enteropathogenic bacteria associated with minimally processed foods sold within Kaduna metropolis. Samples of sliced watermelons, peeled sugarcanes, peeled and sliced pineapples and unshelled coconuts (n=140) were collected from Kaduna North, Kaduna South and Igabi LGAs. Upon enrichment, samples were inoculated onto Eosin-Methylene Blue (EMB) and Cefixime-Tellurite-Sorbitol MacConkey (CT-SMAC) agar and incubated for 18 hours at 35oC. Isolates were identified using MicrobactTM 24E Gram Negative Bacteria Identification System for Enterobacteriaceae. Thereafter, E. coli and Salmonella enterica isolates’ DNA was extracted and purified using AccuPrep Genomic DNA Extraction Kit; used as a template for the PCR amplification of the bundle forming pilus (bfpA) and invasion (invA) genes; and then the PCR products were visualised using agarose gel electrophoresis documentation system. The results of the MicrobactTM analyses showed widespread contamination of the samples with E. coli (22 isolates) and Salmonella enterica (3 isolates). There was no statistically significant difference in the bacterial contaminants isolated from the various sampling areas (one-way ANOVA: p = 0.577); similarly, the type of the minimally processed food samples had no influence on the prevalence of E. coli and Salmonella enterica isolates (p = 0.345). PCR result revealed that the invA virulence gene (284bp) was present in one Salmonella enterica isolate. The presence of invA gene in the Salmonella enterica isolate indicated that the isolate is a virulent strain, which can cause food-borne infections. These results indicated the contamination of the minimally processed fruits with enteropathogens, hence, standards of quality control should be enshrined, towards safer foods and enhanced health of the consuming populace. 

Keywords: E. coli; virulence gene; minimally processed foods; Salmonella enterica.

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The Editorial Board of UJMR is glad to have published the Twelfth edition (Volume 7 Number 1, June, 2022). The Journal covers general and Applied Microbiology, Biotechnology, Biological Sciences, Biochemistry, Bioinformatics, Medical, Public Health and Environmental sciences.

This year, UMYU Journal of Microbiology Research (UJMR) has reached its 5th year of publication which started in 2016. Over these years, many changes have been made to the typeface and general formats of the manuscripts, both the print version and online copies, to make the Journal meet the international standard and more visually appealing. From volume 3 (2) onward, all the online copies of UJMR papers on our website have been uploaded with their full colours. In addition, both authors and co-author are issued with e-certificates of publication for their respective published manuscripts.

We are glad that UJMR is gaining wider acceptance within Nigeria and in some foreign countries, and the number of submissions to the Journal is increasing. Despite the increase in manuscripts, UJMR maintained its quality as reflected by the rigorous peer-reviewing process. All articles submitted are accepted for publication based on a fair, objective, and anonymous assessment by our editors backed by the cogent decision by the editorial board. UJMR has thus increased the number of her associate editors by bringing in more people from academia who are experts in various fields within the scope of the Journal to enhance/maintain the speedy review of manuscripts received from various authors. The UJMR website has been upgraded so that UJMR readers and authors could get vital services such as online submission of manuscripts, downloading UJMR archives, author guidelines, etc.

UJMR’s vision is to be an internationally recognised premier journal of Microbiology, to contribute toward high-quality research and dissemination of UJMR to reach a larger audience worldwide. The journal is now indexed with reputable indexing organizations such as Crossref, Index Corpernicus International, International Institute of Organized Research (I2OR), Google Scholar, CiteSeerX, among others. In addition, the Journal has scored a publication impact factor of 2.525 for the year 2020 and Index Corpernicus value (ICV) of 85.02. Moreover, all our published articles are now assigned DOI. We hope that anyone with the expertise would join us and collaborate with our effort to obtain a much higher Impact Factor. We are delighted that UJMR is the first University-based microbiology journal in Nigeria. Therefore, we urge our academic colleagues to join hands with us towards projecting scientific research.

We appreciate the tireless efforts of the editorial board members, our editorial advisers, associate editors, and authors that contributed towards making UJMR a high-quality research journal. The support extended to the Journal by the Vice Chancellor and Umaru Musa Yar’adua University management is highly appreciated.


Dr. Bashir Abdulkadir

Editor – in – Chief       

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