Pulse EPR spectroscopy and molecular modeling reveal the origins of the local heterogeneity of dietary fibers.
Carbohydr Polym
; 319: 121167, 2023 Nov 01.
Article
en En
| MEDLINE
| ID: mdl-37567691
ABSTRACT
Optimizing human diet by including dietary fibers would be more efficient when the fibers' chain interactions with other molecules are understood in depth. Thereby, it is important to develop methods for characterizing the fiber chain to be able to monitor its structural alterations upon intermolecular interactions. Here, we demonstrate the utility of the electron paramagnetic resonance (EPR) spectroscopy, complemented by simulations in probing the atomistic details of the chain conformations for spin-labeled fibers. Barley ß-glucan, a native polysaccharide with linear chain, was utilized as a test fiber system to demonstrate the technique's capabilities. Pulse dipolar EPR data show good agreement with results of the fiber chain modeling, revealing sinuous chain conformations and providing polymer shape descriptors the gyration tensor, spin-spin distance distribution function, and information about proton density near the spin probe. Results from EPR measurements point to the fiber aggregation in aqueous solution, which agrees with the results of the dynamic light scattering. We propose that the combination of pulse EPR measurements with modeling can be a perfect experimental tool for in-depth structural investigation of dietary fibers and their interaction under such conditions, and that the presented methodology can be extended to other weakly ordered or disordered macromolecules.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fibras de la Dieta
Límite:
Humans
Idioma:
En
Revista:
Carbohydr Polym
Año:
2023
Tipo del documento:
Article