Quantitation of Histamine in Fishes and Fishes Products by High Performance Liquid Chromatography

Abstract

Quantitation of histamine in fishes and fish products was studied by an HPLC-post-column derivatization method.Histamine extracted from samples was separated on a cation exchange column with 0.5M citric buffer (pH 6.4) as a mobile phase, and then derivatized with 0.1% o-phthalaldehyde solution (in borate-KOH buffer, pH 12). o-Phthalaldehyde-histamine complex was determined with a fluorescence detector (excitation at 360nm, emission at 455nm).Commercial fishes (8 samples), fish products (6 samples) and fresh fishes (4 samples) caught in Osaka Bay were analyzed by this method.Among commercial fishes, 5.5ppm of histamine was detected in a jack mackerel. In the case of fish products, high levels of histamine were detected from two dried Japanese pilchards (1050ppm, 382ppm). No trace of histamine was detected in fresh fishes. However, when a fresh mackerel was left to stand at room temperature for 48 hours, the level of histamine in the mackerel increased to 28.4ppm (24 hours) and 1540ppm (48 hours).