The content of phylloquinone (vitamin K1) in human milk, cows' milk and infant formula foods determined by high-performance liquid chromatography.
Phylloquinone (2-methyl-3-phytyl-1,4-naphthoquinone) in human and cows' milk and in infant formula foods has been assayed by a method based on high-performance liquid chromatography (HPLC). The method has three chromatographic steps consisting of a preliminary purification of lipid extracts by conventional liquid chromatography, a further fractionation by semipreparative HPLC and a final analytical step by reversed-phase HPLC in which phylloquinone was resolved from the remaining contaminants and quantified by reference to an internal standard (phylloquinone 2,3-epoxide). The identity of the chromatographic peak ascribed to phylloquinone (vitamin K1) was established by mass spectrometry. Mature human milk from 20 lactating mothers gave a mean concentration of phylloquinone of 2.1 micrograms/liter, and colostrum from 9 mothers gave a mean value of 2.3 micrograms/liter. These levels in human milk were significantly lower than those found in either Friesian (holstein) cows' milk (mean 4.9 micrograms/liter) or unsupplemented infant formula foods containing only cows' milk fat (mean 4.2 micrograms/liter). The mean phylloquinone content of two unsupplemented infant formula foods containing only vegetable oils was 11.5 micrograms/liter. After an oral dose of 20 mg phylloquinone, the concentration of K1 in the breast milk of one mother rose to 140 micrograms/liter after 12 hours and at 48 hours was still about twice the average endogenous level of human milk.
D000328:Adult; D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005260:Female; D006801:Humans; D007225:Infant Food / Q000032:analysis*; D008892:Milk / Q000032:analysis*; D008895:Milk, Human / Q000032:analysis* / Q000378:metabolism; D009821:Oils / Q000032:analysis; D011247:Pregnancy; D010837:Vitamin K 1 / Q000032:analysis* / Q000378:metabolism
D009821:Oils; D010837:Vitamin K 1