title: [Absorption and use of differently structured protein isolates by rats].
abstract: Differently structured isolated proteins with the same amino acid composition were tested with growing albino rats in an N-balance and absorption experiment. The following items were tested: --isolated horse bean protein --hydrolysed isolated horse bean protein with an amino acid supplement to make up for losses due to hydrolysis --horse bean protein-casein (1:1) fibres --isolated horse bean protein with an amino acid supplement to achieve the same amino acid concentrations as in the horse bean protein-casein fibres. The lowest digestibility and utilisation values were ascertained for the hydrolysed protein. Endogenous N-excretion calculated according to the isotope dilution method was higher than for intact proteins, the transport of the chyme in the digestive tract and the true absorption of N in the small intestine had significantly diminished. In comparison with horse bean protein supplemented with amino acids, the horse bean protein-casein fibres showed decreased protein utilisation and increased endogenous N-excretion. Independent of the protein fed and of the time after feeding a relatively constant endogenous N-quota of approximately 70% could be ascertained in the chyme in the small intestine. In contrast to this, the relation between exogenous and endogenous N determined from the contents of the large intestine proved to be dependent on the intermediary utilisation of the protein fed.
mesh_terms: D000596:Amino Acids / Q000008:administration & dosage; D000818:Animals; D002364:Caseins / Q000378:metabolism; D055598:Chemical Phenomena; D002621:Chemistry; D007887:Fabaceae; D005527:Food, Fortified; D007408:Intestinal Absorption; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D014674:Plant Proteins, Dietary / Q000378:metabolism*; D010946:Plants, Medicinal; D011492:Protein Hydrolysates / Q000378:metabolism; D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D000596:Amino Acids; D002364:Caseins; D014674:Plant Proteins, Dietary; D011492:Protein Hydrolysates; D009584:Nitrogen
vernacular_title: Resorption und Verwertung unterschiedlich strukturierter Proteinisolate bei Ratten.