title: Fermentation properties of low-quality red alga Susabinori Porphyra yezoensis by intestinal bacteria.
abstract: Susabinori (Porphyra yezoensis), a red alga, is cultured and processed into a sheet-style dried food, nori, in Japan. But significant amounts of cultured susabinori, which has a low protein content is discarded because of its low quality. The protein content of nori has been reported to be correlated inversely with the carbohydrate content. In this study, we examined the relationship between the protein content and the fermentation of nori by means of bfidobacteria. nori with a low protein content (25% on dry base) was strongly fermented by bifidobacteria, whereas nori with a high protein content (41% on dry base) was not. nori with a low protein content contained large amounts of glycerol galactoside (GG, floridoside: 2-O-glycerol-alpha-D-galactoside, isofloridoside: 1-O-glycerol-alpha-D-galactoside), more than 10% w/w in the dried condition, and GG was the main substrate for fermentation by bifidobacteria. GG was not digested by digestive enzymes, and was not absorbed in the small intestine. These results suggest that GG can be used as a substrate for fermentation by bifidobacteria, and possibility of GG as a prebiotic.
authors.affiliation: Food Science Research Division, Kumamoto Prefectural Fisheries Research Center, Kamiamakusa, Kumamoto, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Muraoka
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishihara
authors.forename: Chiaki
authors.initials: C
authors.lastname: Oyamada
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kunitake
authors.forename: Izumi
authors.initials: I
authors.lastname: Hirayama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kimura
mesh_terms: D000818:Animals; D001644:Bifidobacterium / Q000378:metabolism*; D002241:Carbohydrates / Q000032:analysis; D004063:Digestion; D005285:Fermentation; D005504:Food Analysis; D007408:Intestinal Absorption; D008297:Male; D044664:Porphyra / Q000737:chemistry* / Q000378:metabolism; D011506:Proteins / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D000461:Rhodophyta
chemical_list: D002241:Carbohydrates; D011506:Proteins