Determination of tyramine in cheese by LC-UV.
An isocratic reversed-phase liquid chromatographic assay for tyramine has been developed. The method is based on the reaction of tyramine with 4-chloro-7-nitrobenzofurazan and measurement of the absorbance at 458 nm after chromatographic separation on a C-18 column. Optimum reaction conditions were investigated. A linear relationship was found between absorbance and concentration over the range 25-300 ng per 10 microl of tyramine. The method was applied to the determination of tyramine in cheese. The cheese sample was homogenized with 5% (w/v) HClO(4) extracted with ethyl acetate-acetone (2:1) and chromatographed on high performance liquid chromatography (HPLC) after derivatization reaction with NBD-Cl. The determination limit was 25 microg/g cheese. The mean recovery of tyramine from cheese was 98.0%.
Yigit
Meryem
M
Department of Analytical Chemistry, Faculty of Pharmacy, Istanbul University, 34452 Beyazit, Istanbul, Turkey.
Ersoy
Lale
L
D002611:Cheese / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D014439:Tyramine / Q000032:analysis*
D014439:Tyramine