Effect of Konjac mannan on intestinal microbial metabolism in mice bearing human flora and in conventional F344 rats.
The effects of dietary Konjac mannan (KM), a frequent ingredient of traditional Japanese foods, on intestinal microbial metabolism and microflora composition were investigated using two laboratory animal models, namely, conventional F344 rats and C3H/He male mice bearing human flora. Dietary KM led to a significant reduction in faecal beta-glucuronidase, nitroreductase and azoreductase activities, and in the production of phenol and indole in the faeces of conventional F344 rats. In the C3H/He male mice bearing human flora, faecal beta-glucuronidase and nitroreductase activities were significantly reduced by KM ingestion, as were the amounts of the putrefactive products, p-cresol and indole, in the faeces. Slight differences in intestinal microflora composition between control and KM diet groups were noted. The results indicate that, in C3H/He male mice bearing human flora, dietary KM may modify microbial metabolism without causing significant alterations in intestinal microflora composition.
Fujiwara
S
S
Technical Research Institute, Snow Brand Milk Products Co. Ltd, Saitama, Japan.
Hirota
T
T
Nakazato
H
H
Muzutani
T
T
Mitsuoka
T
T
D000818:Animals; D001419:Bacteria / Q000378:metabolism*; D004043:Dietary Fiber / Q000494:pharmacology*; D005243:Feces / Q000737:chemistry; D005966:Glucuronidase / Q000032:analysis; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D008297:Male; D008351:Mannans / Q000494:pharmacology*; D009601:Nitroreductases / Q000032:analysis; D011134:Polysaccharides / Q000494:pharmacology*; D051381:Rats; D011916:Rats, Inbred F344
D004043:Dietary Fiber; D008351:Mannans; D011134:Polysaccharides; C022901:(1-6)-alpha-glucomannan; D009601:Nitroreductases; D005966:Glucuronidase