ABSTRACT
A method has been developed to discriminate between different dosages of garlic flavoring in tomato sauce with the help of a mass spectrometry based sensory system. Four fragment ions m/z 73, 81, 114, and 120 were selected as "sensor array" during direct injection of the sample headspace into the mass spectrometer. Tomato sauces blended with different types of flavoring could be discriminated, and concentration gradients could be monitored. Fragment ions were chosen after volatile components had been analyzed and identified by SPME-GC/MS and HS-GC/MS (full scan). HS-GC/MS profiles of m/z 73, 81, 114, and 120 were recorded in the selected ion monitoring mode.
Subject(s)
Flavoring Agents/chemistry , Garlic/chemistry , Plants, Medicinal , Solanum lycopersicum/chemistry , Gas Chromatography-Mass SpectrometryABSTRACT
A three-step isolation procedure has been developed for human low molecular weight kininogen resulting in a 385-fold purification of the protein from plasma with an accumulative yield of 8.4%. Human low molecular weight kininogen is a single-chain glycoprotein of apparent molecular weight of 68,000 with a blocked amino-terminus. In the absence of dissociating agents, low molecular weight kininogen reversibly forms homo-oligomers with apparent Mr 185,000 (dimer) to 780,000 (decamer). Limited proteolysis of low molecular weight kininogen by tissue kallikrein liberates kinin and results in the formation of a two-chain molecular with an Mr 62,000 heavy chain of apparent Mr 4000.
Subject(s)
Kininogens/isolation & purification , Carbohydrates/analysis , Electrophoresis, Polyacrylamide Gel , Humans , Kallikreins , Kininogens/blood , Molecular Weight , Peptide Fragments/analysisABSTRACT
From the results obtained in preliminary in vitro experiments we may conclude that the unspecific breakdown of kininogens by neutral and acidic granulocytic proteinases may occur also in the organism during pathological conditions. Inhibitor application may serve as a valuable tool to prevent unspecific proteolytic degradation and thus elimination of kininogens and other clotting or complement factors from their biological function. Furthermore, specific cleavage products of the kininogens produced by granulocytic enzymes may be useful in the diagnosis of a beginning septicemia as well as in elucidation of the primary structure of the human kininogens.
