Sodium ion interaction with psyllium husk ( sp.)

• Published in: Food & function 2016-09, Vol.7 (9), p.441-447
• Main Authors: Jimoh, M. A, MacNaughtan, W, Williams, H. E. L, Greetham, D, Linforth, R. L, Fisk, I. D
• Format: Article
• Language: English
• Subjects: Binding Sites; Chemical Phenomena; Digestion; Gastric Juice - chemistry; Gastric Juice - metabolism; Gels; Humans; Hydrogen-Ion Concentration; Intestinal Mucosa - metabolism; Intestinal Mucosa - secretion; Intestine, Small - metabolism; Intestine, Small - secretion; Kinetics; Models, Biological; Mouth Mucosa - metabolism; Mouth Mucosa - secretion; Nuclear Magnetic Resonance, Biomolecular; Plant Mucilage - chemistry; Plantago; Plantago - chemistry; Prebiotics - analysis; Psyllium - chemistry; Psyllium - metabolism; Sodium, Dietary - analysis; Sodium, Dietary - metabolism; Spectroscopy, Fourier Transform Infrared
• ISSN: 2042-6496; 2042-650X
• DOI: 10.1039/c6fo00785f

The nature of and factors effecting sodium interactions with psyllium were investigated in vitro . In a batch extraction system, psyllium mucilage gel retained at least 50% of sodium across a range of concentrations (5-300 mg sodium per g psyllium) and pH (2-10) environments. FTIR and Na NMR analyses of psyllium gels indicated that binding was complex with non-specific multi-site interactions. The potential use of psyllium husk as a binding agent for the reduction of bioavailable sodium was therefore evaluated. The binding of sodium at physiologically relevant conditions (pH 1.2 (stomach) and 6.8 (intestine)) was studied in a gastrointestinal tract (GIT) pH simulated model. Results show consistently high sodium retention (∼50%) across the GIT model and less than 20% loss of bound sodium under the simulated intestinal pH conditions after repeated washings. The nature of and factors effecting sodium interaction with psyllium were investigated in vitro . The feasibility of use of psyllium husk to reduce the bioavailable fraction of ingested sodium is demonstrated.