Evaluation of Fish Decomposition by Liquid Chromatographic Assay of ATP Degradation Product

A liquid chromatographic method is described for quantitative determination of nucleotide derivatives adenosine 5 -triphosphate, adenosine 5 -diphosphate, adenosine 5 -monophosphate, inosine 5 '- monophosphate, inosine, and hypoxanthine in fish. The nucleotide derivatives are extracted by grinding the flesh in cold perchloric acid, recovered, precipitated from the acid by 5M KOH, and analyzed. Nucleotide derivatives and internal standard (purine) were separated in 14 min with a new elution gradient on a reversed-phase column (Kromasil C18) at 25 C. The column was regenerated in 20 min. Regression lines gave strong correlation coefficients. This new method is fast, accurate, and more objective than the Fresh-Tester, acolorimetric determination of a ratio AC used to measure freshness. It shows that the ratio K cannot be used as a universal measure of fish decomposition.