SCREENING FOR ANTIBIOTIC RESISTANCE GENES IN ESCHERICHIA COLI AND SALMONELLA ENTERICA ISOLATED FROM DRINKING WATER FROM PARTS OF KADUNA STATE, NIGERIA

Simple item page
dc.contributor.authorOLUKOSI, Olajoke Mofoluke
dc.date.accessioned2017-10-16T07:54:37Z
dc.date.available2017-10-16T07:54:37Z
dc.date.issued2017-02
dc.descriptionA THESIS SUBMITTED TO THE SCHOOL OF POSTGRADUATE STUDIES, AHMADU BELLO UNIVERSITY, ZARIA IN PARTIAL FULFILLMENT FOR THE AWARD OF A DOCTOR OF PHILOSOPHY DEGREE IN MICROBIOLOGY DEPARTMENT OF MICROBIOLOGY, FACULTY OF LIFE SCIENCES, AHMADU BELLO UNIVERSITY, ZARIA, NIGERIA.en_US
dc.description.abstractThis study investigated drinking water from some parts of Kaduna state, Nigeria for multi-drug resistant Escherichia coli and Salmonella enterica (serovars Typhi and Typhimurium). The physicochemical and bacteriological qualities of the water samples were also investigated. This was done by determining some parameters such as the BOD, DO, conductivity, turbidity and also determining the presence and level of some heavy metals such as copper, chromium and iron. The total and faecal coliform counts were determined, together with the presence of Escherichia coli (O157:H7 and non-O157) and Salmonella enterica. A total of five hundred water sources (borehole, tap, well, stream and packaged water) were sampled from six local government areas in Kaduna state between March 2014 and February 2015, which included the wet and dry seasons (246 and 254 samples respectively). The mean conductivity and total dissolved solids content of the borehole samples were significantly higher than all other samples, while tap water had the least content. Furthermore, the mean values of the samples collected in the wet and dry seasons showed that the values of the nitrate, pH and Lead were significantly higher during the wet season (P<0.05).Packaged and borehole water were observed to be of relatively better physicochemical quality than water from other sources. Standard procedures were used for the identification of the target organisms and for estimating the total and faecal coliform counts of the water samples. The faecal coliform counts were significantly higher during the wet season as compared to the dry season. A total of 178 isolates were characterized biochemically, of which 73(46%) and 12(2.4%) of them were Escherichia coli and Salmonella enterica respectively. Six of the E. coli isolates were confirmed serologically to belong to the O157:H7 group by testing with a latex agglutination kit, while the Salmonella enterica were confirmed to belong to the Typhi and Typhimurium serovars. Other bacteria detected included Proteus mirabilis, Hafnia alvei, Enterobacter aerogenes, Citrobacter freundii and Klebsiella pneumoniae. Antibiotic susceptibility tests to ten commonly used antibiotics were carried out using the Kirby-Bauer method. The highest resistance observed by E.coli and Salmonella enterica was to Tetracycline (56.1 and 77.8% respectively). Forty (97.6%) of the E. coli isolates were susceptible to Chloramphenicol and Gentamicin, while all the 9 Salmonella enterica isolates (100%) were susceptible to Amoxycillin, Amoycillin-clavulanic acid, Ampicillin, and Gentamicin. One isolate was resistant to six of the antibiotics, while three were resistant to seven antibiotics. These multidrug resistant isolates were gotten from various water sources. Eight of them were isolated from borehole water, six from packaged water and one from stream water. Polymerase Chain Reaction was used to assay for the presence of some virulence genes, antibiotic resistance genes and 16S rRNA genes. Some of the isolates produced amplicons for the following genes: stx2, invA, eaeA, hlyA, sul1, blaTEM, tetA, tetB and 16S rRNA. However, none of the isolates tested produced amplicons for the stx1, spvA and cmlA genes. The 16S rRNA genes were further subjected to sequencing, and the sequences were analysed using the Basic Local Alignment Search Tool (BLAST) on the National Center for Biotechnology Information (NCBI) website, thereby confirming their identities. Other strains of E. coli were identified after sequencing such as E. coli O104:H4 and E. coli IAI39. The Salmonella enterica isolates were confirmed to belong to the Typhi and Typhimurium serovars. Bottled water proved to be of better bacteriological quality as compared to other water sources. These results show that many of the water samples had been contaminated by faecal sources, and xxii The presence of multi-drug resistant strains also indicates a great risk to consumers especially those who drink these waters without any further treatment.en_US
dc.identifier.urihttps://kubanni.abu.edu.ng/handle/123456789/9272
dc.language.isoenen_US
dc.subjectSCREENINGen_US
dc.subjectANTIBIOTIC RESISTANCE GENESen_US
dc.subjectESCHERICHIA COLI,en_US
dc.subjectSALMONELLA ENTERICA,en_US
dc.subjectDRINKING WATER,en_US
dc.subjectKADUNA STATE,
dc.subjectNIGERIA
dc.titleSCREENING FOR ANTIBIOTIC RESISTANCE GENES IN ESCHERICHIA COLI AND SALMONELLA ENTERICA ISOLATED FROM DRINKING WATER FROM PARTS OF KADUNA STATE, NIGERIAen_US
dc.typeThesisen_US
Files
Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
SCREENING FOR ANTIBIOTIC RESISTANCE GENES IN ESCHERICHIA COLI AND SALMONELLA ENTERICA ISOLATED FROM DRINKING WATER FROM PARTS OF KADUNA STATE, NIGERIA.pdf
Size:
1.96 MB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.62 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
SCIENCE