Plasmid Profile of isolated Bacteria from Arinta Waterfall in Ipole-Iloro Ekiti

This research determined the microbial counts, antibiotics susceptibility and plasmid profile of the isolated bacteria of water samples from Arinta waterfall Ipole-Iloro Ekiti, Ekiti State, Nigeria. The total bacterial and coliform counts were done using pour plating technique while the susceptibility of the isolated microbes were determined using disc diffusion technique the plasmid profile of the isolates was determine using alkaline lysis method and agar gel electrophoresis. The mean total bacterial count of the water sample ranged 106 X 102 – 15.5 X 103 CFU/ml, while the mean coliform count ranged 97.5 X 102 – 6.50 X 103 CFU/ml. The identified bacteria isolates and their percentage distribution are Escherichia coli which have the highest percentage (31.1%), Klebsiella spp. (22.2%), Pseudomonas spp. (8.89%), Citrobacter spp. (6.67%), Salmonella spp. (6.67%), Serratia spp. (6.67%), Bacillus spp. (4.44%), Aeromonas spp. (4.44%), Micrococcus spp. (4.44%) and Aerococcus spp. (4.44%). Among these ten species, multiple antibiotics resistant bacteria were identified. The most active antibiotics were ofloxacin (14%), ciprofloxacin (28%) and gentamicin (17%). 99.6% of the isolates exhibited multiple antibiotic resistances. Eight bacterial isolates harbored plasmids all of which were not less than 2.51kbp in molecular weight. Hence, it showed that the gene coding for the isolates were located on the plasmid DNA while the remaining isolates which have no plasmid might showed gene coding for antibiotic resistance being located on chromosomal DNA. The occurrence of plasmid mediated multidrug resistant in bacteria in this surface water lightens the public health concern.