Quantitative assessment of faecal bifidobacterial populations by real-time PCR using lanthanide probes.
OBJECTIVE
To develop real-time quantitative PCR methods, based on the use of probes labelled with a stable fluorescent lanthanide chelate, for the quantification of different human faecal bifidobacterial populations.


RESULTS
The designed quantitative PCR assays were found to be specific for the corresponding Bifidobacterium species or groups (Bifidobacterium longum group, Bifidobacterium catenulatum group, Bifidobacterium adolescentis, Bifidobacterium breve, Bifidobacterium angulatum, Bifidobacterium bifidum and Bifidobacterium dentium). The detection limits of the methodologies used ranged between 2 x 10(5) and 9 x 10(3) cells g(-1) of faeces. The applicability of the developed assays was tested by analysing 20 human faecal samples. Bif. longum group was found to be the qualitatively and quantitatively predominant bifidobacterial group.


CONCLUSIONS
The real-time PCR procedures developed here are specific, accurate, rapid and easy methods for the quantification of Bifidobacterium groups or species in human faecal samples.


CONCLUSIONS
The developed procedures will facilitate rapid and objective counting of large numbers of samples increasing our knowledge on the role of gut bifidobacterial microbiota in health and disease. This will contribute to the efficient use of intestinal bacterial assays in research, food and pharmaceutical development as well as in the assessment of dietary management of diseases.
Gueimonde
M
M
Functional Foods Forum, Department of Biochemistry and Food Chemistry, University of Turku, Turku, Finland. mgueimonde@ipla.csic.es
Debor
L
L
Tölkkö
S
S
Jokisalo
E
E
Salminen
S
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001644:Bifidobacterium / Q000145:classification* / Q000302:isolation & purification; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000032:analysis*; D005243:Feces / Q000382:microbiology*; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods*; D013045:Species Specificity
D004269:DNA, Bacterial