No abstract

The survival in the rat small intestine of soybean agglutinin or Kunitz or Bowman-Birk trypsin inhibitors was studied by SDS-and native polyacrylamide gel electrophoresis, transblotting, trypsin inhibitor activity assays, and immunochemical determinations. As the inhibitors were bound in enzyme complexes in the small intestine, functional assays were unsuitable. However, as free and bound inhibitors reacted similarly with their antibodies, survival could be assayed by immunoblotting and ELISA. In addition to the mucosa-bound agglutinin, 8.6% of the original dose was free in the gut lumen and this, by moving further down in the small intestine, could have extended the wasteful gut growth from proximal to distal parts. Although only 4.8% of the Bowman-Birk inhibitor survived, most (76%) of the Kunitz inhibitor remained immunochemically intact. Accordingly, stimulation of pancreatic growth and enzyme secretion by the inhibitors, particularly the Kunitz, may have contributed to the total antinutritive effect of soybean.

No abstract

Biogenic amines in grapes, aszu-grapes, wines, and aszu-wines of the Tokaj region of Hungary were separated, identified, and quantified by HPLC. The biogenic amine content of the Tokaj wines was well below the suggested limits for any of the biogenic amines. Histamine contents were especially low in all the samples investigated. The composition and concentration of the biogenic amines (polyamines) in the grape berries were altered remarkably by the Botrytis cinerea, and this resulted in a great change of the amine concentration in the aszu-wines compared to the wines. The composition and concentration of biogenic amines might provide useful information on the vintage and can support the authentication of the Tokaj aszu-wines.

SummaryThe biologically active amines agmatine, cadaverine, histamine, phenethylamine, putrescine, spermidine, and tyramine have been determined in different varieties of grape, aszu grape, wine and aszu wine from the Tokaj region of Hungary. Ion pairs formed between the amines and octanesulphonic acid were separated by liquid chromatography on a #Bondapak C18 reversed-phase column, and spectrofluorimetric detection was performed after post-column derivatization with o-phthalaldehyde and 2-mercaptoethanol. The method was linear for the amines between 0.1 and 10 mg L -1, and for spermidine between 1 and 30 mg L 1. Comparison of the results revealed that the qualitative and quantitative content of biologically active amines was mostly determined by the vintage of the wine and the technology used for wine-making. The biogenic amine content of Tokaj wines is well below suggested limits for any of the amines, showing that the winemaking technology of the Tokaj region is of high quality. The levels of biologically active amines (identified and quantified by HPLC) in grapes, wines and aszu wines can provide useful information about the weather, growth of Botrytis cinerea in Tokaj, and aspects of the methods used for wine-making.