MOLECULE

Phylloquinone

Phylloquinone or Phytonadione is often called vitamin K1. Vitamin K1 is a polycyclic aromatic ketone, based on 1,4-naphthoquinone, with 2-methyl and 3-phytyl substituents. Vitamin K is a family of phylloquinones that contain a ring of 2-methyl-1,4-naphthoquinone and an isoprenoid side chain. Several forms of vitamin K have been identified: vitamin K1 derived from plants, vitamin K2 (menaquinone) from bacteria and synthetic naphthoquinone provitamins, and vitamin K3 (menadione) (PMID: 27337968). Vitamin K1 has only one double bond on the proximal isoprene unit. It possesses the same type and degree of activity as does naturally occurring vitamin K, which is necessary for the production via the liver of active prothrombin (factor II), proconvertin (factor VII), plasma thromboplastin component (factor IX), and Stuart factor (factor X). Rich sources of vitamin K1 include green plants, algae, and photosynthetic bacteria. Vitamin K1 has antihemorrhagic and prothrombogenic activity. Vitamin K1 is a fat-soluble vitamin that is stable to air and moisture but decomposes in sunlight. Phylloquinone is also an antidote for coumatetralyl. As in many plants, vitamin K is also found in Cannabis sativa (PMID: 6991645).