Determination of Phylloquinone and Menaquinones in Animal Products with Fluorescence Detection after Postcolumn Reduction with Metallic Zinc
Terhi J. Koivu-Tikkanen, Velimatti Ollilainen, Vieno Piironen
Journal of Agricultural and Food Chemistry
Abstract
A high-performance liquid chromatographic (HPLC) method for the determination of phylloquinone and menaquinones in foods of animal origin is described. The K vitamers were quantified with a fluorescence detector after postcolumn reduction with metallic zinc using K1(25) as an internal standard. Extraction was done either with 2-propanol-hexane (meat and fish products) or with acid hydrolysis method (dairy products). Prior to quantification, sample extracts were purified by semipreparative HPLC; in addition, the fats of cheese and rainbow trout samples were removed with lipase hydrolysis. By this method the phylloquinone and menaquinones (MK-4 to MK-10) present in a few representative samples of different animal food groups were determined. HPLC-MS was used to confirm the identification of K vitamers. Long-chain menaquinones were found from bovine and pig livers as well as from various cheeses. The total vitamin K contents calculated as the sum of quantified K vitamers were in general low (mean content 10-100 ng/g); the highest amount was analyzed in chicken meat (600 ng/g).
Extracted Claims
6 claims extracted from this paper into the knowledge graph
phylloquinone and menaquinones determined animal products
“A high-performance liquid chromatographic (HPLC) method for the determination of phylloquinone and menaquinones in foods of animal origin is described.”
phylloquinone and menaquinones extracted meat and fish products
“Extraction was done either with 2-propanol-hexane (meat and fish products) or with acid hydrolysis method (dairy products).”
fats removed cheese and rainbow trout samples
“Prior to quantification, sample extracts were purified by semipreparative HPLC; in addition, the fats of cheese and rainbow trout samples were removed with lipase hydrolysis.”