Determination of D-amino acids, derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F), in wine samples by high-performance liquid chromatography.

The concentrations of D-amino acids and their enantiomeric ratios in wind samples were determined by high-performance liquid chromatography with fluorometric detection. We used Pirkle type chiral stationary phases and fluorogenic reagent, 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) for simplicity and high sensitivity. The amino acids determined were D-enantiomers of alanine (Ala), aspartic acid, glutamic acid, isoleucine (Ile) and leucine (Leu), D-Asparagine, -glutamine and -lysine were not detected. D-Leu was detected in red and rosé wine samples, and D-Ile was determined only in rosé wine. In contrast, neither D-Leu nor Ile were detected in white wine samples. The concentration of D-Ala was the most prominent among these amino acids with the highest content of approximately 180 microns (D/D + L ratio; 25%) in rosé wine.