Determination of vitamin K composition of fermented food

Food Chem. 2019 Mar 1;275:515-522. doi: 10.1016/j.foodchem.2018.09.136. Epub 2018 Sep 24.

Abstract

A rapid ultra-high performance liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometric (UHPLC-APCI-MS/MS) method was developed for the analysis of vitamin K compounds: phylloquinone (PK) and menaquinones (MK-n). Non-chlorinated mobile phase composition was optimized for separation of eight vitamin K compounds on a reversed phase column in 10 min. Sample treatment with liquid and solid phase extractions and by the use of MK-4 as an internal standard enabled the quantitation of microgram level of vitamin K compounds in food. The method was used to screen and quantitate vitamin K from 17 fermented food products. The highest amount of PK was detected in kimchi (42 µg/100 g), whereas the highest MK-7 content was detected in natto (902 µg/100 g). Some MK-9 was present in kefir (5 µg/100 g). Two Chinese fermented soybean pastes contained significant amount of MK-6 (5-36 µg/100 g), MK-7 (12-86 µg/100 g), and MK-8 (22-44 µg/100 g).

Keywords: Fermentation; Menaquinone; Phylloquinone; Tandem mass spectrometry; UHPLC; Vitamin K.

MeSH terms

  • Atmospheric Pressure
  • Chromatography, High Pressure Liquid
  • Fermented Foods and Beverages / analysis*
  • Tandem Mass Spectrometry
  • Vitamin K / chemistry*

Substances

  • Vitamin K