title: Failure of d-psicose absorbed in the small intestine to metabolize into energy and its low large intestinal fermentability in humans.
abstract: Experiments with rats have produced data on the metabolism and energy value of d-psicose; however, no such data have been obtained in humans. The authors assessed the availability of d-psicose absorbed in the small intestine by measuring carbohydrate energy expenditure (CEE) by indirect calorimetry. They measured the urinary excretion rate by quantifying d-psicose in urine for 48 hours. To examine d-psicose fermentation in the large intestine, the authors measured breath hydrogen gas and fermentability using 35 strains of intestinal bacteria. Six healthy subjects participated in the CEE test, and 14 participated in breath hydrogen gas and urine tests. d-Psicose fermentation subsequent to an 8-week adaptation period was also assessed by measuring hydrogen gas in 8 subjects. d-Psicose absorbed in the small intestine was not metabolized into energy, unlike glucose, because CEE did not increase within 3 hours of d-psicose ingestion (0.35 g/kg body weight [BW]). The accumulated d-psicose urinary excretion rates were around 70% for 0.34, 0.17, and 0.08 g/kg BW of ingested d-psicose. Low d-psicose fermentability was observed in intestinal bacteria and breath hydrogen gas tests, in which fructooligosaccharide (0.34, 0.17, and 0.08 g/kg BW) was used as a positive control because its available energy is known to be 8.4 kJ/g. Based on the results of the plot of breath hydrogen concentration vs calories ingested, the energy value of d-psicose was expected to be less than 1.6 kJ/g. Incremental d-psicose fermentability subsequent to an adaptation period was not observed.
authors.affiliation: Research Laboratory, Matsutani Chemical Industry Co, Ltd, Itami 664-8508, Japan. tetsuo-iida@matsutani.co.jp
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Iida
authors.forename: Noriko
authors.initials: N
authors.lastname: Hayashi
authors.forename: Takako
authors.initials: T
authors.lastname: Yamada
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yoshikawa
authors.forename: Shoko
authors.initials: S
authors.lastname: Miyazato
authors.forename: Yuka
authors.initials: Y
authors.lastname: Kishimoto
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Okuma
authors.forename: Masaaki
authors.initials: M
authors.lastname: Tokuda
authors.forename: Ken
authors.initials: K
authors.lastname: Izumori
mesh_terms: D000328:Adult; D001419:Bacteria / Q000378:metabolism; D001682:Biological Availability; D001944:Breath Tests; D004734:Energy Metabolism; D005260:Female; D005285:Fermentation; D005632:Fructose / Q000378:metabolism* / Q000493:pharmacokinetics* / Q000652:urine; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000382:microbiology; D008297:Male
chemical_list: C003243:psicose; D005632:Fructose; D006859:Hydrogen