Fate and effects of Camembert cheese micro-organisms in the human colonic microbiota of healthy volunteers after regular Camembert consumption.
The objective of this study was to determine i) if Camembert cheese micro-organisms could be detected in fecal samples after regular consumption by human subjects and ii) the consequence of this consumption on global metabolic activities of the host colonic microbiota. An open human protocol was designed where 12 healthy volunteers were included: a 2-week period of fermented products exclusion followed by a 4-weeks Camembert ingestion period where 2x40 g/day of Camembert cheese was consumed. Stools were collected from the volunteers before consumption, twice during the ingestion period (2nd and 4th week) and once after a wash out period of 2 weeks. During the consumption of Camembert cheese, high levels of Lactococcus lactis and Leuconostoc mesenteroides were measured in fecal samples using real-time quantitative PCR, reaching median values of 8.2 and 7.5 Log(10) genome equivalents/g of stool. For Ln. mesenteroides, persistence was observed 15 days after the end of Camembert consumption. The survival of Geotrichum candidum was also assessed and the fecal concentration reached a median level of 7.1 Log(10) CFU/g in stools. Except a decreasing trend of the nitrate reductase activity, no significant modification was shown in the metabolic activities during this study.
Unité d'Ecologie et Physiologie du Système Digestif, INRA, 78350 Jouy-en-Josas, France.
Olivier
O
Firmesse
Elise
E
Alvaro
Agnès
A
Mogenet
Jean-Louis
JL
Bresson
Riwanon
R
Lemée
Pascale
P
Le Ruyet
Cécile
C
Bonhomme
Denis
D
Lambert
Claude
C
Andrieux
Joël
J
Doré
Gérard
G
Corthier
Jean-Pierre
JP
Furet
Lionel
L
Rigottier-Gois
D000328:Adult; D002611:Cheese / Q000382:microbiology*; D003106:Colon / Q000382:microbiology*; D015169:Colony Count, Microbial; D018592:Cross-Over Studies; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D005243:Feces / Q000382:microbiology*; D005260:Female; D005516:Food Microbiology; D005848:Geotrichum / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D007778:Lactobacillus / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D008297:Male; D050901:Nitrate Reductase / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D048249:Streptococcus thermophilus / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D013997:Time Factors
D004269:DNA, Bacterial; D004271:DNA, Fungal; D050901:Nitrate Reductase