Preparation and characterisation of a novel agar oligosaccharide–iron (III) complex

Abstract

This study aimed to synthesise a complex of agar oligosaccharides (AOS) with ferric iron and to evaluate its physicochemical and structural characteristics. Based on single factor, Plackett-Burman and response surface optimal experiments of three factors at three levels, the optimised chelate conditions of the AOSiron (III) complex were mass ratio of AOS to iron ions of 4.5:1 g:g, reaction temperature of 74°C and reaction time of 60 min. Under these conditions, the iron content and total sugar content were 14.03 AE 0.42% and 66.07 AE 0.96%, respectively. The physicochemical analysis showed that AOS-iron (III) was soluble and steady at physiological pH, and it was easily reduced to iron (II). The structural characteristics of AOS and AOS-iron (III) were analysed by Raman spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction and Nuclear magnetic resonance, and results showed that the iron (III) ions were chelated to AOS by -OH groups and -COOH groups and widely dispersed on the AOS backbone. Therefore, AOS-iron (III) could be a candidate for iron supplementation to treat iron deficiency anaemia.

Co-cultured Lepista sordida and Pholiota nameko polysaccharide-iron(iii) chelates exhibit good antioxidant activity

“…23 400 to 1000 cm À1 were characteristic peaks of iron core structure "b-FeOOH" of polysaccharide-iron(III) chelates. 24 In our study, the weak absorption peak of CP-1-Fe and CP-3-Fe at 450 and 850 cm À1 were observed, respectively. The absorption peak at around 1060 cm À1 in polysaccharide and polysaccharide-iron(III) was indicated the existence of a pyran-ring structure.…”

Effectiveness of AOS–iron on iron deficiency anemia in rats

“…AOS-iron was synthesized as described previously. 26 The steps in the preparation of AOS-iron were as follows. First, 0.25 g AOS and 0.125 g sodium citrate were dissolved in 10 mL distilled water, and the pH was adjusted to 5.00 AE 0.05 with 1 mol L À1 HCl.…”

Synthesis and Characterization of a Novel Apple Pectin–Fe(III) Complex

“…Recent studies on polysaccharide–Fe(III) complexes indicated that the −OH and −COOH groups were bound to Fe 3+ . 24 , 37 , 38 Therefore, it was speculated that −OH and −COOH groups in the pectin chains acted as a bridge to connect Fe 3+ in the AP–Fe(III).…”

“…In addition, the AP–Fe (III) complex comprised a β-FeOOH structure, which was obtained by comparison with the standard spectrum. Recent studies on polysaccharide–Fe­(III) complexes indicated that the −OH and −COOH groups were bound to Fe 3+ . ,, Therefore, it was speculated that −OH and −COOH groups in the pectin chains acted as a bridge to connect Fe 3+ in the AP–Fe­(III).…”