ABSTRACT
Fish meal extract bile esculin agar (FMBE) is prepared using Fish meal extract concentrate as the basal substance, for the selective isolation and presumptive identification of B.fragilis group. The efficiency of the medium was evaluated by growing stock cultures of B.fragilis groups as well as inoculating clinical specimens and comparing the results with Bacteroides bile esculin agar (BBE). All the 87 stock cultures of B.fragilis grew on FMBE and BBE. No other anaerobes tested grew on the medium. However 7 out of 65 neomycin resistant aerobes grew on the FMBE. From the 100 clinical samples, 62 strains of B. Fragilis group were recovered on FMBE and BBE, and 53 strains on supplemented BHIBA. The cost effectiveness, selectivity and the ability to detect esculin hydrolysis will enable FMBE as a suitable medium as comparable to that of BBE, if not superior.
Subject(s)
Agar , Animals , Bacteriological Techniques , Bacteroides fragilis/growth & development , Bile , Culture Media , Esculin , Fishes , HumansABSTRACT
Bacteriodes fragilis group can inhibit the phagocytosis and killing of co-existing aerobes. Forty six strains of B.fragilis group are tested for their ability to resist phagocytosis and inhibit the killing of indicator organism, E. coli by denoting the viable count. Among the species of B. fragilis group, the inhibitory index of the phagocytic system was the highest with B. fragilis followed by B. thetaiotamicron. None of the strains of B. fragilis group were phagocytosed or killed in this system. This property of resisting the phagocytosis and killing of E. coli by B. fragilis group might be the contributing factor towards their prevalence in mixed infections.
Subject(s)
Bacteroides/immunology , Bacteroides fragilis/immunology , Blood Bactericidal Activity , Colony Count, Microbial , Escherichia coli/immunology , Humans , Neutrophils/immunology , PhagocytosisABSTRACT
The adhesive properties of the B. fragilis group to various erythrocytes were studied by haemagglutination technique and compared to encapsulation. Of the 61 strains of Bacteroides groups tested, only 40 strains of B. fragilis exhibited haemagglutination. Treatment of the organisms with carbohydrates and trypsin had no effect on haemagglutination, but boiling for one hour completely destroyed this property. Haemagglutinating activity of B. fragilis was found to be the highest with chick and tanned sheep erythrocytes. The presence of capsule was observed in 46 strains of B. fragilis group. Of the 40 strains of B. fragilis which exhibited agglutination, capsule was found only in 37. The findings of the study suggest a polysaccharide nature for the adhesin. The different patterns of haemagglutination, suggest the involvement of more than one adhesin. Capsule in capsulated strains and fimbriae in non-capsulated strains might be mediating the property of haemagglutination.
Subject(s)
Bacterial Adhesion , Bacterial Capsules , Bacteroides fragilis/physiologyABSTRACT
A spectrum of three different anaerobes were isolated from a debilitated patient with suppurative lung disease, within a two-year period. Repeated isolation from three consecutive samples and symptomatic relief with metronidazole provide clinical evidence of anaerobic lung infection. This case emphasizes the importance of anaerobic culture in cases of protracted pulmonary suppurative disease.
Subject(s)
Bacteria, Anaerobic/isolation & purification , Bacteroides fragilis/isolation & purification , Clostridium/isolation & purification , Humans , Lung Diseases/microbiology , Male , Middle Aged , Peptostreptococcus/isolation & purification , SuppurationABSTRACT
Sixty bronchoalveolar lavage samples collected from lung cancer patients attending the Pulmonary Tuberculosis and Chest Diseases Unit of the Kasturba Medical College Hospital, Manipal; were cultured for both the aerobic and anaerobic organisms. Fifty nine samples yielded bacteria in pure culture. Pseudomonas aeruginosa (34.8%) was the commonest aerobe, Peptostreptococcus was the commonest anaerobe (45.2%) isolated. Bacteroides fragilis was isolated in (23.8%) of cases. Gentamycin was found to be effective against aerobes, Metronidazole and Rifampicin against anaerobes.
Subject(s)
Bacteria, Aerobic/isolation & purification , Bacteria, Anaerobic/isolation & purification , Bronchoalveolar Lavage Fluid/microbiology , Female , Humans , Immunocompromised Host , Lung Neoplasms/microbiology , MaleABSTRACT
Bile from 25 patients with obstructive jaundice was cultured for both aerobic and anaerobic organisms. Twenty one samples were positive for culture. Mixed bacterial growth was seen in 5 (20%) of the bile samples 25 aerobes and one anaerobic were isolated. Escherichia coli was the commonest aerobic isolate and Bacteroides fragilis was the single anaerobe isolated. Majority of the aerobes isolated were sensitive to gentamycin.
Subject(s)
Bacteria, Aerobic/isolation & purification , Bile/microbiology , Cholestasis/microbiology , Escherichia coli/isolation & purification , HumansABSTRACT
A study of blood cultures from 320 cases of neonatal sepsis showed 136 (42.5%) to be positive for bacterial growth; of these 82 (60.29%) isolates being gram negative bacilli. Citrobacter was the commonest gram negative bacilli isolated. Other commonly isolated gram negative organisms were Pseudomonas, Klebsiella, Salmonella typhimurium, Acinetobacter and Escherichia coli. Antibiotics susceptibility pattern revealed the isolates to be resistant to commonly used antibiotics.