Abstract
Inclusion complex formation of eight kinds of lipid-soluble vitamins with 6-O-α-D-glucopyranosyl-β-cyclodextrin (G-β-CD) in aqueous solution and in solid phase were assessed by the sulubility method and thermal analysis. All lipid-soluble vitamins were highly solubilized in water by complexation with G-β-CD. From analysis of the phase solubility diagrams, the stoichimetric ratio of the main complex in water was estimated to be 1 : 2 for vitamin (V) A alcohol/G-β-CD, 1 : 2 for V D2/G-β-CD, 1 : 1 for V D3/G-β-CD, 1 : 3 for V E/G-β-CD, 1 : 4 for V E nicotinate/G-β-CD, 1 : 3 for V K1/G-β-CD, 1 : 3 for V K2/G-β-CD, and 1 : 1 for V K3/G-β-CD. The stabilities of lipid-soluble vitamins in water containing G-β-CD were examined. A V E nicotinate-G-β-CD complex solution was stable even under irradiation with light.
