title: [Mucin: a probable endogenous substrate of intestinal fermentation].
abstract: Using a previously described technique to measure fecal fermentation, a study was done on the effect which, on basal fermentation of 19 stool samples, had the addition of mucin and the addition of lactose, in amounts equivalent for carbohydrate content. The addition of mucin elevated basal fecal fermentation clearly and similarly to the addition of lactose. The increase in basal fecal fermentation when mucin was added was similar for the stools with normal basal fermentation than for the stools with exaggerated basal fermentation; and the same happened when lactose was added. It seems that what decides the level of fecal fermentation is not so much the fermentative capacity of bacteria present in the stools, which would be practically unlimited, but the amount of fermentable substrates already present in the stools or added to them. If, as it was previously suggested, the level of fecal fermentation in an individual reflects the state of its intestinal fermentation, the latter would consequently depend not so much from the fermentative capacity of bacteria present in the terminal ileum and colon but from the amount of fermentable substrates which arrive to those intestinal zones. It is extremely interesting that mucin, an endogenous substrate, that is, which is produced in the digestive tract, be as good a source for generation of gas by bacterial action as lactose, an exogenous substrate of recognized importance in the genesis of flatulence.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005243:Feces / Q000382:microbiology*; D005260:Female; D005285:Fermentation; D005740:Gases; D006801:Humans; D007422:Intestines / Q000502:physiology*; D007785:Lactose / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism*
chemical_list: D005740:Gases; D009077:Mucins; D007785:Lactose
vernacular_title: Mucina: un probable substrato endógeno de fermentación intestinal.