Bî-tá-mín K sī iû bî-tá-mín K1 (phylloquinone), K2 (menaquinone), kap K3 (menadione) só͘ cho͘-sêng ê chi̍t cho͘ bî-tá-mín. K1 chhàng tī chheⁿ-sek ê hio̍h-á--nih, K2 ē-sái iû tōng-bu̍t tn̂g-á lāi ê sè-khún ha̍p-sêng, ah K3 sī jîn-kang ha̍p-sêng ê. Bî-tá-mín K gâu hō͘ sng, kiⁿ, kap ióng-hoà-che lâi phò-hāi, tùi kng bô ún-tēng, siāng-hó ài pó-chûn tī àm-sek ê kan-á--nih. Bî-tá-mín K ē-sái pang-chàn jîn-thé ha̍p-sêng chē-chē tiōng-iàu ê kek-hoeh in-chú, nā-chún ū khiàm tio̍h-ē chō-chiâⁿ kek-hoeh kong-lêng ê koh-iūⁿ.

VitaminK1.pngVitaminK2.png
Figure 1: Chemical structures of vitamin K1 (phylloquinone, left structure) and vitamin K2 (menaquinones, right structure). Both contain a functional naphthoquinone ring and an aliphatic side chain. Phylloquinone has a phytyl side chain, whereas in menaquinone the side chain is composed of a varying number of isoprenoid residues.