Search

The viscosity is a foundational parameter of biomacromolecule in the food industry. The viscosity of macroscopic colloids is closely related to the dynamical behaviors of mesoscopic biomacromolecule clusters, which are difficult to be investigated at molecular resolution by common methods. In this study, based on experimental data, multi-scale simulations combining microscopic molecular dynamics simulation, mesoscopic Brownian dynamics simulation, and macroscopic flow field construction were used to investigate the dynamical behaviors of mesoscopic clusters of konjac glucomannan (KGM) colloids (~500 nm) over a long time (~100 ms). Numerical statistical parameters of the mesoscopic simulation of macroscopic clusters were proposed and proved to represent the viscosity of colloids. Based on the intermolecular interaction and macromolecular conformation, the mechanism of the shear thinning effect was revealed as both the regular arrangement of macromolecules at low shear rates (<100 s−1) and structural collapse of macromolecules at high shear rates (>500 s−1). Then, the effect of molecular concentration, molecular weight, and temperature on the colloid viscosity and cluster structure of KGM colloids was investigated by experiments and simulations. This study provides a novel multi-scale numerical method and insight into the viscosity mechanism of biomacromolecule. The viscosity mechanism of konjac glucomannan colloids was investigated by experiments and multi-scale simulations. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective: To improve the bioavailability of active substances and reduce the toxic and side effects on the human body, natural biological macromolecules are used to load active substances and control their release speed in different environments of the human body. In this study, mesoporous silica (MSN) was combined with konjac glucomannan (KGM) and sodium alginate (AC) to prepare pH-sensitive konjac glucomannan/sodium alginate-mesoporous silica loaded naringin gel spheres (KS/MSN). On this basis, the structure, morphology, and release properties of the composite gel spheres were characterized. The results showed that the cumulative release rates of both simulated gastric fluid (SGF) and Simulated colonic fluid (SCF) were lower than that of simulated small intestinal fluid (SIF), which indicated that the prepared composite gel spheres were pH-sensitive to SIF and obtained the best release rate of about 70% under SIF environment., Methods: The pH-sensitive konjac glucomannan/sodium alginate composite gel spheres (KGM/SA) were prepared by combining inorganic nano-materials mesoporous silica (MSN) with natural macromolecular polysaccharides konjac glucomannan (KGM) and sodium alginate (SA) and characterized., Results: The results showed that there was a process of ionic crosslinking and entanglement between konjac glucomannan (KGM) and sodium alginate (SA). Naringin (NG) and mesoporous silica (MSN) were successfully compounded and had good compatibility. The gel microstructure diagram showed that the addition of MSN improved the gel properties of KGM, and KGM and SA gel spheres (KGM/SA) had good compatibility with mesoporous silica/naringenin nanoparticles (NG/MSN). The study of the simulated digestive environment of the gastrointestinal release medium showed that Konjac glucomannan/sodium alginate-mesoporous silica loaded naringin gel spheres (KS/NM) composite gel spheres had the best slow-release effect and the highest final-release completion degree in SIF. The release of NG from KS/NM composite gel spheres showed a slow upward trend. The results showed that KS/NM composite gel spheres were pH-sensitive., Conclusion: The KS/NM composite gel spheres showed obvious pH sensitivity to the release of NG, and the gel spheres had a good sustained release effect on NG., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Dao, Chen, Sun, Pang, Zhang, Liao, Yan and Pang.)