Dilute Solution Viscometry Studies on a Therapeutic Mixture of Non-digestible Carbohydrates

Abstract

Abstract:Recent work has shown the beneficial effects of a proprietary mixture of three non-digestible carbohydrates: konjac glucomannan, xanthan and alginate and these effects have been linked with a synergistic interaction observable with analytical ultracentrifugation, rheological and NMR measurements. These observations have been supported by fundamental dilute solution viscosity studies. Preparations of konjac glucomannan, xanthan and alginate have been checked with regards their molecular integrity (molar mass distribution) using a newly established method based on the analytical ultracentrifuge. The intrinsic viscosity behaviour for each of the individual polysaccharides were estimated at low ionic strength I (10 -3 M) and found to be (2090±120) ml/g, (4430±340) ml/g and (3460±330) ml/g for konjac glucomannan, xanthan and alginate respectively and at (10 -1 M) (2350±200) ml/g, (3370±310) ml/g and (1210±50) ml/g respectively. The intrinsic viscosity [η] was then determined for a proprietary mixture of the three (known as "PGX®") at both ionic strengths and compared with the predicted values for a non-interacting mixture. In I=10 -3 M solvent a significant difference was observed (3090+250) ml/g compared with the predicted value (2350+300) ml/g, although at higher ionic strength the interaction appears to have gone: [η] = (1990+250) ml/g compared with the predicted value of (2180+300) ml/g. This appears to reinforce the earlier observations that in PGX® there is a synergistic interaction which is ionic strength sensitive.

Effect of the Novel Polysaccharide PolyGlycopleX® on Short-Chain Fatty Acid Production in a Computer-Controlled in Vitro Model of the Human Large Intestine

“…The carbohydrate properties of PGX have been previously described [12,13,14] and show that an interaction between a konjac glucomannan–xanthan gum complex and sodium alginate forms a new, ternary complex.…”

“…The experimental fibers were: (1) Positive control: Fructo-oligosaccharide from chicory (Sigma Aldrich Chemie BV, Zwijndrecht, The Netherlands); (2) Negative control: Cellulose (VWR International BV, Roden, The Netherlands); (3) Test fiber: PolyGlycopleX ® (PGX ® ), a soluble high viscosity polysaccharide (HVP) manufactured by a proprietary process (EnviroSimplex ® ) from three dietary fibers; konjac (glucomannan), sodium alginate and xanthan gum (PGX ® : α- d -glucurono-α- d -manno-β- d -manno-β- d -gluco, α- l -gulurono-β- d -mannurono, β- d -gluco-β- d -mannan; InovoBiologic Inc., Calgary, Canada). The carbohydrate properties of PGX have been previously described [ 12 , 13 , 14 ] and show that an interaction between a konjac glucomannan–xanthan gum complex and sodium alginate forms a new, ternary complex.…”

Safety of alginate‐konjac‐xanthan polysaccharide complex (PGX) as a novel food pursuant to Regulation (EC) No 258/97

“…Harding et al. () reported that the intrinsic viscosity of PGX, which was measured with analytical ultracentrifugation, was higher than the predicted value for the unprocessed mixture of the three NSP. The authors concluded that there is a synergistic interaction among the three NSP in PGX, which is sensitive to the ionic strength of the solvent.…”

“…The applicant claimed that PGX is a ‘novel complex’ rather than a mixture of the three NSP. In this respect, different parameters have been compared between PGX and the three NSP: sedimentation, precipitation, viscosity and macromolecular interactions (Abdelhameed et al., ; Harding et al., , ; Smith et al., ).…”