Bifidobacteria in the Culture Collection
Bifidobacterium longum CCOS 606
Bifidobacteria are potential health-promoting lactic acid bacteria present in the human gastrointestinal tract. In the large intestine, bifidobacteria contribute to the production of butyrate which is an important energy source for the colonic mucosa (Kleerebezem and Vaughan 2009). Selection criteria for probiotic bacteria are: human origin, GRAS (generally recognized as safe) status, suitable for large scale production, bile acid resistance, adherence to human intestinal cells and intestinal mucins, ability to modulate immune response, antimicrobial activity, efficacy and proven safety (Kolida et al. 2006; Dunne et al. 2001).
Beneficial effects associated with bifidobacteria include: reduction of duration of diarrhoea (Rerksuppaphol and Rerksuppaphol 2010), protection of intestinal cells from pathogenic bacteria (Chenoll et al. 2011), inhibition of inflammation (Philippe et al. 2011; Roselli et al. 2006), folate production (Santacruz et al. 2010; Pompei et al. 2007) and reduction of serum cholesterol levels (Lee et al. 2009).
Under the microscope, bifidobacteria show different forms: straight rods, forked or bifid rods, branched or globular swelling of rods (Husain et al. 1972).
Characterisation of Bifidobacteria
Moderately oxygen-tolerant Bifidobacterium strains were isolated from faeces of infant and adult humans by the institute for microbiology and biotechnology of the Max Rubner Institute in D-Kiel and further characterised by the CCOS. More than 60 different strains are available from CCOS.
Table 1: Properties of selected Bifidobacterium strains
| Property | Bifidobacterium | ||||||
| bifidum | breve | breve | longum | longum | longum | animalis subsp. lactis |
|
| CCOS no. | 571 | 549 | 586 | 522 | 527 | 545 | 594 |
| Origin: Feces of | infant | infant | infant | adult | infant | infant | adult |
| Ox bile resistance1 | 1% | 0.5% | 0% | 1% | 1% | 1% | 1% |
| Haemolysis on sheep blood | gamma | gamma | beta | beta | gamma | gamma | gamma |
| Adherence2 | +++ | ++ | nd | +/++ | +/- | - | ++ |
| Ratio IL-10/IL-123 | < 1 | 1.7 | nd | < 1 | < 1 | 1.7 | nd |
| Folate production4 µg 100g-1 DW |
8000 | 200 | nd | 800 | 500 | 300 | 1350 |
1Growth on agarplate with indicated ox bile concentration
2Adherence of the strains to Caco-2 and HT-29 cells were determined using FACS analysis.
3IL-10/IL-12 cytokine ratio was determined by incubation of human peripheral blood mononuclear cells (ZEN-Bio, SER-PBMC-200) with the different strains using ELISA.
4Determination of folate production of lyophilized strains in folate-free medium using HPLC-M.
Abbreviations: DW: Dry weight; nd: not determined
Table 2: Antibiotic resistance patterns of selected Bifidobacterium strains:
| Antibiotic | MIC in µg mL-1 of Bifidobacterium | ||||||
| bifidum | breve | breve | longum | longum | longum | animalis subsp. lactis | |
| CCOS no. | 571 | 549 | 586 | 522 | 527 | 545 | 594 |
| Ampicillin | 0.06 | 0.5 | nd | 2 | 0.12 | 0.5 | nd |
| Chloramphenicol | 1 | 8 | nd | 1 | 0.5 | 2 | 0.5 |
| Ciprofloxacin | 16 | 0.25 | 1 | 64 | 8 | 8 | 4 |
| Clindamycin | 0.06 | 0.25 | 0.03 | 0.06 | 0.03 | 0.06 | 0.03 |
| Erythromycin | 0.03 | 0.12 | 0.016 | 0.06 | 0.016 | 0.06 | 0.016 |
| Gentamycin | 32 | 16 | 2 | 16 | 16 | 8 | 8 |
| Kanamycin | 256 | 128 | 4 | 256 | 128 | 128 | nd |
| Linezolid | 2 | 0.5 | nd | 0.5 | 0.5 | 1 | 0.5 |
| Neomycin | 64 | 64 | 1 | 64 | 32 | 32 | 4 |
| Penicillin | 0.12 | 0.5 | nd | 1 | 0.12 | 0.5 | nd |
| Rifampicin | 0.5 | 0.25 | 0.12 | 0.12 | 0.25 | 0.25 | 0.25 |
| Streptomycin | 32 | >256 | 0.5 | 32 | 16 | 16 | 16 |
| Tetracycline | 1 | 16 | 0.5 | 0.5 | 0.25 | 1 | 16 |
| Trimethoprim | >64 | >64 | 0.5 | 32 | 2 | 8 | 0.12 |
| Vancomycin | 1 | 0.5 | 0.25 | 0.5 | 0.5 | 0.25 | 0.25 |
| Virginiamycin | 0.25 | 0.12 | 0.03 | 0.03 | 0.06 | 0.12 | nd |
Antibiotic susceptibility testing was performed according to ISO 10932 using VetMIC and/or Etest systems. nd: not determined