TITLE:
Identification of Bifidobacterium animalis, Bifidobacterium adolescentis and Bifidobacterium bifidum from Stool of Children and Detection of Their Antibacterial Properties
AUTHORS:
Mansour Amin, Ahmad Farajzadeh Sheikh, Hamed Goodarzi, Mehdi Sormeh
KEYWORDS:
Bifidobacterium; PCR; Antimicrobial Substance; Stool
JOURNAL NAME:
Advances in Infectious Diseases,
Vol.3 No.3,
September
5,
2013
ABSTRACT: Introduction
and Objective: The genus Bifidobacterium can generally
be found in quantity in the habitats such as human and animal gastrointestinal
tract, dental caries, vagina and oral cavity. The aim of this study was to
isolate Bifidobacterium from stool and determine their inhibitory effect
against some pathogens. Materials and Methods: 130 samples were collected by wet swabs and kept in sterile tubes
containing MRS broth media. And Bifidobacterium isolated from stool was
enriched in Man-Rogosa-Sharpe medium (MRS) broth and isolated by growing on MRS
agar medium and characterized by phenotypic characteristics and PCR technique
at genus and species levels. The antimicrobial substance was extracted from
ethyl acetate solvent and the antimicrobial activity against some pathogenic
bacteria, such as Salmonella typhi and Shigella sonnei, were investigated. Results: Eleven Bifidobacterium bifidum and four Bifidobacterium adolescentis, which were isolated from fresh stool, were identified by PCR. Antimicrobial
substance from MRS broth medium was extracted. This antimicrobial compound
showed a potent inhibitory activity against four tested bacteria. These
bacteria produced acetic acid and lactic acid as inhibitory substances that were
different from bacteriocins. Conclusion: Fresh stool may be used as a source of antimicrobial lactic acids
bacteria, Bifidobacterium bifidum and adolescentis as two
probiotics can establish themselves in gut and urogenital tract to prevent the
human body from adverse effects of pathogens.