Isolation of Bacteriophages from surface water for some distinct bacterias and their characterization as potential biocontrol agents
Abstract
E. coli of many different kinds, most of which are part of the intestine's normal flora and are
thought to be comparatively harmless. However, some strains have developed pathogenicity
systems, which means they can cause disease in humans and livestock. Like this harmful strain,
there are some other harmful pathogenic Bacteria are found in sewage water or wastewater.
Through this sewage water, this microbes can contaminate our drinking water. Which might
become the cause of different intestinal disease. These can be intestinal (diarrhoea) or
extraintestinal (UTI), septicaemia and pneumonia. 75% to 95% Urinary tract infection is caused
by a certain type of E. coli. Some types of E. coli can produce Shiga toxin which damages the
line of the intestine. This type of E. coli strain is called STEC which is short for “Shiga Toxin
producing E. coli”. O157: H7 is another effective strain of E. coli which typically causes
abdominal cramps, vomiting and bloody diarrhoea when it is consumed through contaminated
food or water. Shigella dysenteriae spread by contaminated water causes the most severe
dysentery because of its potent and deadly Shiga toxin. Typhoid fever is caused by Salmonella
typhi bacteria, it infects the intestinal tract and blood. Vibrio causes vibriosis or cholera. The
primary objective of this project was to isolate bacteriophage against E. coli and to recognize
its different characteristics as an antimicrobial agent to determine the therapeutic potential. In
this study, specific bacteriophage for all these six bacteria was isolated and characterized to
develop a therapeutic agent. A total number of 60 samples were collected for the study of this
experiment. The samples were collected from the wastewater of different cities of Dhaka city.
The samples were initially filtered and the double layer- agar method was used for the isolation
of bacteriophages. For the characterization of bacteriophages, host range specificity test, Heat
stability and pH stability were checked. After examination of the host range, the most
prominent bacterial hosts were ETEC, EAEC, Shiga-toxin producing E. coli (STEC), O157:H7,
Klebsiella pneumonia and Shigella dysenteriae were lysed by E. coli phage. In the case of
bacteriophage isolations, clear zones were observed which indicates the presence of phages.
This research, therefore, adds to the increasing amount of isolated bacteriophages, especially
the particular bacteriophage of E. coli. Studies on its biological features may provide helpful
data and understanding to identify prospective therapeutic agents against infection with E. coli.