Microcalorimetry of the intestinal mucus: Hydrogen bonding and self-assembly of mucin.

Int J Biol Macromol

School of Food Science and Bioengineering, Zhejiang Gongshang University, Xiasha, Hangzhou, Zhejiang 310016, China; Department of Food Technology, ATEI of Thessaloniki, 57400 Thessaloniki, Greece. Electronic address:

Published: June 2018

The effect of mucin hydrogen bonding on the structure of intestinal mucus has been studied with micro-differential scanning mirocalorimetry (μ-DSC), supported by spectroscopy. The experiments were performed in water-dimethyl sulfoxide (DMSO) solutions, using either water-DMSO mixtures of an appropriate DMSO content or water as blanks, as to isolate the effects of the solvent to hydrogen bonding. When using matched water-DMSO blanks, thermal events at low temperatures are linked to the negation of mucin-DMSO interactions, while events at higher temperatures are linked to the break-up of hydrogen bonds connecting the sugars of the individual macromolecules. When using a matched solvent as blank, alterations in C, such as increases at 10% and 15% DMSO, have been linked to the break-up and creation of quaternary structures. In the case of water as blank, a monotonic but not linear decrease in enthalpy, hence extent of hydrogen bonding, is observed. The above are complemented by UV spectroscopy: A blue shift of the conjugated aminoacids in the presence of DMSO suggests that the inherent stability of mucin is not only due to steric volume exclusions, but also due to extensive hydrogen bonding on behalf of the sugar moieties.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijbiomac.2018.01.185DOI Listing

Publication Analysis

Top Keywords

hydrogen bonding
20
intestinal mucus
8
temperatures linked
8
linked break-up
8
hydrogen
6
bonding
5
microcalorimetry intestinal
4
mucus hydrogen
4
bonding self-assembly
4
self-assembly mucin
4

Similar Publications

Pharmaceuticals removal from aqueous solution by water hyacinth (Eichhornia crassipes): a comprehensive investigation of kinetics, equilibrium, and thermodynamics.

Environ Sci Pollut Res Int

January 2025

Grupo de Investigación Materiales Con Impacto (Mat&Mpac), Facultad de Ciencias Básicas, Universidad de Medellín, Carrera 87 No. 30-65, 050026, Medellín, Colombia.

This study shows the efficiency of WH-C450, an adsorbent obtained from water hyacinth (WH) biomass, in the removal of sulfamethoxazole (SMX) from aqueous solutions. The process involves calcination of WH at 450 °C to produce an optimal adsorbent material capable of removing up to 73% of SMX and maximum SMX adsorption capacity of 132.23 mg/g.

View Article and Find Full Text PDF

Molecular spin qubits have the advantages of synthetic flexibility and amenability to be tailored to specific applications. Among them, chromophore-radical systems have emerged as appealing qubit candidates. These systems can be initiated by light to form triplet-radical pairs that can result in the formation of quartet states by spin mixing.

View Article and Find Full Text PDF

Due to health reasons of polyglycerol polyricinoleate (PGPR), there has been a growing interest in reducing it. To address this, this study developed the PGPR/Protein (whey, pea, and chickpea protein isolates) emulsifier combinations. The effects of these combinations on the preparation, structure, physicochemical and in vitro digestive properties of W/O/W microcapsules were evaluated.

View Article and Find Full Text PDF

Gold(I)-Catalyzed 2-Deoxy-β-glycosylation via 1,2-Alkyl/Arylthio Migration: Synthesis of Velutinoside A Pentasaccharide.

J Am Chem Soc

January 2025

Molecular Synthesis Center, Key Laboratory of Marine Drugs of Ministry of Education, Shandong Key Laboratory of Glycoscience and Glycotherapeutics, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.

2-Deoxy-β-glycosides are essential components of natural products and pharmaceuticals; however, the corresponding 2-deoxy-β-glycosidic bonds are challenging to chemically construct. Herein, we describe an efficient catalytic protocol for synthesizing 2-deoxy-β-glycosides via either IPrAuNTf-catalyzed activation of a unique 1,2--positioned C2--propargyl xanthate (OSPX) leaving group or (PhO)PAuNTf-catalyzed activation of a 1,2--C2--alkynylbenzoate (OABz) substituent of the corresponding thioglycosides. These activation processes trigger 1,2-alkyl/arylthio-migration glycosylation, enabling the synthesis of structurally diverse 2-deoxy-β-glycosides under mild reaction conditions.

View Article and Find Full Text PDF

Where Does the Proton Go? Structure and Dynamics of Hydrogen-Bond Switching in Aminophosphine Chalcogenides.

Angew Chem Int Ed Engl

January 2025

University of Regensburg, Faculty of Chemistry and Pharmacy, Institute of Inorganic Chemistry, Universitätsstraße 31, D-93053, Regensburg, GERMANY.

Aminophosphates are the focus of research on prebiotic phosphorylation chemistry. Their bifunctional nature also makes them a powerful class of organocatalysts. However, the structural chemistry and dynamics of proton-binding in phosphorylation and organocatalytic mechanisms are still not fully understood.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!