ANTIBACTERIAL SUSCEPTIBILITY PATTERN OF BIOFILM PRODUCING BACTERIA ISOLATED FROM PACKAGED DRINKING WATER SOLD IN OWERRI METROPOLIS, IMO STATE, NIGERIA

Azuwike C. O. Ekwerike, C. U., Ajuruchi, V. C. and Braide W.*

ABSTRACT

Water is an essential natural resource required by all living organisms. Biofilm is as association of microorganism in which cells stick to each other on a surface encased within a matrix of extracellular polymeric substance produced by bacteria themselves. This study was done to isolate, characterize and show antibiotic susceptibility of biofilm producing bacteria in packaged drinking water sold in Owerri metropolis. One hundred (100) samples each was collected randomly from seven locations to make a total of seven hundred (700) samples. The sample were analysed using membrane filtration and standard plate count methods. The identities of the bacterial isolates were confirmed with standard bacteriological manual. Sample from Eziobodo, Nazi, FUTO campus and Obinze recorded higher bacterial population. Eleven genera of bacteria were isolated from the samples with their percentage occurrence as follows: Staphylococcus aureus (23.1%), Bacillus cereus (10.4%), Klebsiella sp (4.0%), Pseudomonas aeruginosa (10.5%), Enterobacter sp (3.3%) and Enterococcus faecalis (19.5%), E. coli (7.2%), Corynebacterium sp (4.7%), Micrococcus leteus (7.9%), Micrococcus roseus (5.8%) and Shigella sp (3.6%). The result of the antibiotic susceptibility test shows that all the biofilm producing bacteria in the water samples have 100% resistance to chloramphenicol, 99% to streptomycin, 98% to erythromycin and 90% to gentamycin. Bacillus cereus, Corynebacterium sp and Enterococcus faecalis were resistant to at least four antibiotics. The diseases caused by biofilm producing bacteria and their ability to resist antibiotics had been reported. Microbiological assessment of quality of drinking water should be done periodically by the regulatory agencies in compliance with internationally defined drinking water standards. The results of multiple antibiotic resistances obtained from this study challenges scientist on the need for more or development of new antibiotics to fight against the infections caused by these resistant strains.

Keywords: Biofilm, bacteria, antibiotics, resistance.