BACTERIOCINS PRODUCED BY L. FERMENTUM AND L .ACIDOPHILUS CAN INHIBIT CEPHALOSPORIN RESISTANT E .COLI

Ano: 2010 | Volume: 41 | Número: 3

Autores: Saba Riaz, Syed Kashif Nawaz, Shahida Hasnain

Palavras-chave: Cephalosporin resistant Escherichia coli, Bacteriocin, Antibiotic resistance, Lactobacillus fermentum, Lactobacillus acidophilus

Resumo Inglês:

Reemerging infections occur due to resistant bacteria. Such infections create restrictions for clinicians and
microbiologists in drug selection. Such problems demand new strategies for solution. Use of bacteriocins
for this purpose may be fruitful. In the present research work, the inhibitory effects of bactericins on
cephalosporin resistant Escherichia coli are used as model system for the control of antibiotic resistant
pathogenic bacteria. Cephalosporin resistant Escherichia coli strain was isolated from pus by using
conventional methodology. For bacteriocin production, Lactobacilli strains were selected by using
selective media. Out of seventy two strains isolated from yogurt, fecal materials of human, chick, parrot
and cat, only two strains (strain 45 and strain 52) were found to produce bacteriocins having antimicrobial
potential against cephalosporin resistant Escherichia coli. Biochemical characterization showed that strain
45 belonged to group of Lactobacillus fermentum and strain 52 to Lactobacillus acidophilus. Both strains
showed maximum growth at 25°C and 35°C respectively. Suitable pH was 5.5 and 6.0 for Lactobacillus
fermentum and Lactobacillus acidophilus respectively. Bacteriocins produced by both strains were found
stable at 50, 75 and 100°C for 60min. Function of bacteriocin was also not disturbed due to change in pH.
These findings suggest that bacteriocin produced by Lactobacillus fermentum and Lactobacillus
acidophilus can be used for the infection control of cephalosporin resistant Escherichia coli.