title: In vitro protein degradation of 38 sainfoin accessions and its relationship to tannin content by different assays.
abstract: This study compared 38 sainfoin and 2  Lotus  accessions to their respective tannin contents, N buffer solubility, and in vitro protein degradation. Tannin contents were measured by a protein precipitation method using either bovine serum albumin or Rubisco and by the colorimetric HCl/butanol method. Precipitation of bovine serum albumin and Rubisco was highly correlated (R(2) = 0.939). Correlations between the protein precipitation variants and the HCl/butanol method were relatively low (R(2) < 0.6). Protein degradation was measured at 4 h of incubation in an inhibited in vitro system and could not be explained by any of the tannin assays (R(2) < 0.03) and only partially by N buffer solubility (R(2) ≤ 0.433). Decisive factors other than the quantity of tannins or their ability to precipitate proteins must be considered. Resistance of soluble protein toward degradation can possibly be caused by tannin protein binding.
authors.affiliation: Department of Animal Nutrition and Management,  Swedish University of Agricultural Sciences SLU , Kungsängen Research Centre, 753 23 Uppsala, Sweden.
authors.forename: Martin M
authors.initials: MM
authors.lastname: Lorenz
authors.forename: Christine
authors.initials: C
authors.lastname: Hayot Carbonero
authors.forename: Lydia
authors.initials: L
authors.lastname: Smith
authors.forename: Peter
authors.initials: P
authors.lastname: Udén
mesh_terms: D011232:Chemical Precipitation; D007887:Fabaceae / Q000737:chemistry*; D000070116:Lotus / Q000737:chemistry*; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D059748:Proteolysis; D012273:Ribulose-Bisphosphate Carboxylase / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012995:Solubility; D013634:Tannins / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D011506:Proteins; D013634:Tannins; D012710:Serum Albumin, Bovine; D012273:Ribulose-Bisphosphate Carboxylase