Determination of L- and D-amino acids in foodstuffs by coupling of high-performance liquid chromatography with enzyme reactors.
A technique is described for the enantiomeric determination of L- and D-amino acids. It works on the principle that the separation efficiency of high-performance liquid chromatography is coupled with the specificity of enzymes and the sensitivity of electrochemical detection. After separation on a lithium cation-exchange column the amino acids are converted into keto acids and hydrogen peroxide under catalyzation of L- or D-amino acid oxidase. Hydrogen peroxide is detected amperometrically. The method has been tested by the analysis of beer, port, sherry, wine and fruit juice. A main emphasis was put onto the determination of D-alanine which can serve as an indicator for bacterial contamination. It is shown that a coupling of HPLC with enzyme reactors is a suitable technique for the rapid detection of this marker.
Voss
K
K
Institute of Food Science and Food Chemistry, University of Bonn, Federal Republic of Germany.
Galensa
R
R
D000594:Amino Acid Oxidoreductases / Q000378:metabolism; D000596:Amino Acids / Q000737:chemistry* / Q000378:metabolism; D001419:Bacteria; D001515:Beer / Q000032:analysis; D015374:Biosensing Techniques; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry; D005504:Food Analysis / Q000379:methods*; D005516:Food Microbiology; D005638:Fruit / Q000737:chemistry; D011786:Quality Control; D014920:Wine / Q000032:analysis
D000596:Amino Acids; D000594:Amino Acid Oxidoreductases