|Budget Amount *help
¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1991 : ¥1,000,000 (Direct Cost : ¥1,000,000)
The final purpose of this study is to evaluate the available energy of bulking sugar substitutes which are not hydrolyzed by digestive enzymes and fermented by intestinal microbes in the lower intestine. The available energy of non-digestible and fermentable oligosaccharides could not be estimated by the traditional methods. Because, it is disregarded that short chain fatty acid which is produced from nondigestible sugar substitutes by intestinal microbes, contributes to the host as energy source. However, the experiments using Neosugar demonstrated clearly that oligosaccharide which is not hydrolyzed by digestive enzymes, reaches to the large intestine and is fermented completely by intestinal microbes (Oku et al. J. Nutr., 114 & 119).
This study advocated the new method which estimates the available energy on the basis of fermentation equation. The details of method is described in elsewhere (1, 2, 3, 4). In order to estimate the available energy on the basis of fermentation equation,
the digestion, absorption, fermentation, excretion and metabolic pathway of the test substance have to be clarified. In this study, Neosugar, maltitol and erythritol which the metabolic property are greatly different each other, were used.
The metabolism of Neosugar has been already investigated. The outline of metabolism of maltitol has also been studied. This study demonstrated that about 10% of total maltitol ingested was digested and absorbed and about 90% of the total was fermented in the large intestine (4, 5). Further, intestinal bacteria which utilizes maltiol, is different from that for Neosugar and maltitol appears to be utilized by yeast and fungi (4). Maltiol was not hydrolyzed by enzymes of large intestinal musosa.
Tetrose alcohol erythritol was readily absorbed from small intestine and excreted quickly into the urine without any degradation (6, 7, 8). The excretion ratio was about more than 90% of total ingestion (6, 7). In the administration of very large amount, the urinary excretion of erythritol decreased and the ratio of fermentation increased (7). The available energy of erythritol was the lowest in reduced-energy sugar substitutes (7, 8). Less