Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus survive gastrointestinal transit of healthy volunteers consuming yogurt

• Published in: FEMS microbiology letters 2005-09, Vol.250 (2), p.185-187
• Main Authors: Mater, Denis D.G., Bretigny, Laurent, Firmesse, Olivier, Flores, Maria-Jose, Mogenet, Agnès, Bresson, Jean-Louis, Corthier, Gérard
• Format: Article
• Language: English
• Subjects: Adult; Animal, plant and microbial ecology; Bacteria; Bacteriology; Biological and medical sciences; Colony Count, Microbial; Feces; Feces - microbiology; Female; Fundamental and applied biological sciences. Psychology; Gastrointestinal system; Gastrointestinal tract; Gastrointestinal Tract - microbiology; Growth, nutrition, cell differenciation; Human trial; Humans; Lactobacillus delbrueckii; Lactobacillus delbrueckii - physiology; Life Sciences; Male; Microbial ecology; Microbiology; Microbiology and Parasitology; Middle Aged; Selective media; Streptococcus thermophilus; Streptococcus thermophilus - physiology; Survival; Transit; Various environments (extraatmospheric space, air, water); Yogurt; Yogurt - microbiology
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1016/j.femsle.2005.07.006

To date, there is significant controversy as to the survival of yogurt bacteria (namely, Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) after passage through the human gastrointestinal tract. Survival of both bacterial species in human feces was investigated by culture on selective media. Out of 39 samples recovered from 13 healthy subjects over a 12-day period of fresh yogurt intake, 32 and 37 samples contained viable S. thermophilus (median value of 6.3 × 10 4 CFU g −1 of feces) and L. delbrueckii (median value of 7.2 × 10 4 CFU g −1 of feces), respectively. The results of the present study indicate that substantial numbers of yogurt bacteria can survive human gastrointestinal transit.