The main objective of the study is to realized a collection of feces in order to study the modification of the intestinal microflora according to alimentary fibres

Human intestinal tract count up to 1014 bacteria. We consider that each bacterial flora is composed of more than 500 different species among which only 20% are cultivable. Although this flora is well unknown, it is known that it play a major role in the metabolism of the eating fibers. Dysfunctions of this flora may be implied in numerous local and general pathologies.

It has been shown that probiotics and prebiotics are able to act upon the intestinal flora. On the basis of the personal real-life, it is generally considered acquired that our diet modifies this flora. However not many studies have validated this hypothesis with human normal diet (not artificially enriched with prebiotics or probiotics). The idea that our diet can modified the functioning of our intestinal flora (and so favor certain pathologies or activate recovery) is widely hypothetic.

A best knowledge of the diversity of this flora and to put at disposal tools to study it on a large scale could allow to answer this question. The demonstration that some food components could modify the composition or the functioning of this flora would have considerable consequences in medicine and food processing industry.

Inclusion Criteria:

• BMI between 18,5 and 25

Exclusion Criteria:

• Antibiotherapy in the previous month
• Current Antibiotherapy
• Gastro-intestinal dysfunction
• Pregnancy, parturient and feeding woman
• Person deprived of freedom by judiciary or administrative decision, person in legal protection,
• Prebiotic and/or osmotic laxatives in the previous month
• Preparation for coloscopy in the previous month