Oil soluble iron: Curcumin derivatives and their complex

Abstract

Curcumin dibutanoate (CUDB) is a new oil soluble bidentate ligand which shows higher stability against heat and oxidation compared to curcumin. The oil solubility of this ligand increased an order of magnitude over curcumin. This biomolecule showed high digestibility in a simulated intestinal trial and was hydrolyzed in the presence of porcine pancreatin releasing ∼ 91% of the curcumin. When curcumin dibutanoate was complexed with Fe²⁺, Fe(CUDB)₂ was formed as a new iron (II) complex. Due to the high hydrophobicity of the curcumin dibutanoate ligand, the solubility of Fe(CUDB)₂ was found to be 2.8 mg/mL in canola oil. The steric hindrance afforded by the CUDB ligand, coupled with its hydrophobicity stabilized the iron (II) oxidation state within the complex compared to FeSO₄·7H₂O as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Fe(CUDB)₂ has potential to be a new form of oil-soluble iron supplement which co-delivers iron (II) and curcumin.

Keywords: Curcumin dibutanoate; Digestible ligand; Fe(CUDB)(2); Oil soluble ligand; Oil-soluble iron (II) complex.