Effect of pectin with different esterification degree on the freeze-thaw stability of gluten protein: Structures, functional properties, and Cryoprotective mechanism

The synergistic effect of hydroxypropyl methylcellulose and κ-carrageenan or pectin on anti-freezing

Ten polysaccharides were mixed to select polysaccharides with the synergistic anti-freezing effect in this study. It was found that hydroxypropyl methylcellulose (HPMC) and pectin (PEC) or κ-carrageenan (κ-CAR) synergistically decreased the freezing temperature of water and enhanced the ice recrystallization inhibition activity. Moreover, HPMC/κ-CAR exhibited greater synergy than HPMC/PEC. Raman spectroscopy analysis demonstrated that these polysaccharides increased the disorder of water molecules and inhibited the transition from liquid water to solid ice, and HPMC and PEC or κ-CAR had a synergistic effect on increasing the disorder of water molecules. Particularly, dynamic ice-shaping measurements showed that the HPMC/κ-CAR mixture changed circular ice into hexagonal ice in 20.0 % sucrose solution, whereas the HPMC/PEC mixture did not. Moreover, κ-CAR was more compatible with HPMC than PEC. The above differences might explain why κ-CAR was more effective than PEC in improving the anti-freezing ability of HPMC.

Plant-based meat: The influence on texture by protein-polysaccharide interactions and processing techniques

As interest in sustainable food production grows, significant strides have been made in developing plant-based meat products. However, this field is still in its early stages and faces several challenges, with replicating the texture of animal meat being the most critical hurdle. Therefore, this review provides a comprehensive overview of the key proteins and polysaccharides commonly used in plant-based meat formulations. It delves into the covalent and non-covalent interactions between these protein and polysaccharide molecule, and examines how these molecular interactions, along with various processing techniques, influence the texture of plant-based meat. Specifically, it highlights the role of conformational changes in proteins that support the formation of a stable structural matrix. This review aims to provide foundational insights to deepen the understanding of plant-based meat, supporting its further application and innovation.

Prolamin-pectin complexes: Structural properties, interaction mechanisms and food applications

Prolamin, a class of plant protein mainly derived from grains, and pectins, complex-structured polysaccharides, are natural biological macromolecules with versatile functional properties. The interactions between prolamins and pectin have been widely studied and applied, demonstrating that both covalent and non-covalent interactions play pivotal roles in the formation of prolamin-pectin complexes. These interactions impart exceptional physicochemical and functional properties to the complexes. This review also details the main applications of prolamin-pectin complexes, including emulsions, nanoparticles, hydrogels and films. The similarities in their reaction principles are based on the interaction of complexes that improve their physicochemical and functional properties, while the difference lies in the specific modes of action, involving the emulsifying properties, self-assembly properties, gelling properties and film-forming properties of prolamin and pectin. By delving into the intricate mechanisms underlying prolamin-pectin interactions and their diverse applications in the food industry, this review offers valuable insights for advancing the development and utilization of these complexes.

Preparation, structural property, and antioxidant activities of a novel pectin polysaccharide from the flowers of Hibiscus syriacus Linn

Introduction

Oxidative stress, triggered by an imbalance between reactive oxygen species (ROS) production and cellular antioxidant defense mechanisms, is implicated in various pathological conditions. Plant-derived polysaccharides have gained significant attention as potential natural antioxidants due to their biocompatibility, biodegradability, and structural versatility.

Methods

This study focuses on the purification, structural characterization, and antioxidant activities of a novel pectin polysaccharide (HFPS) isolated from the flowers of Hibiscus syriacus Linn. HFPS was purified using anion-exchange chromatography. Its chemical composition, monosaccharide profile, molecular weight distribution, and structural properties were elucidated through various analytical techniques.

Results

HFPS exhibited a predominant acidic monosaccharide composition, with galacturonic acid as the major constituent, indicating its pectin nature. The free radical scavenging activity of HFPS against ABTS·, DPPḤ, and ·OH radicals was evaluated, demonstrating a positive correlation between its antioxidant capacity and concentration. Furthermore, HFPS effectively protected HepG2 cells against H2O2-induced oxidative stress by reducing ROS accumulation, modulating redox-related enzymes (Superoxide dismutase, Catalase, Glutathione peroxidase), and alleviating oxidative damage. Notably, HFPS upregulated the expression of antioxidant-related genes, including B-cell lymphoma-2 (Bcl-2), heme oxygenase 1 (HO-1), NAD(P)H quinone oxidoreductase 1 (NQO1), and nuclear factor erythroid 2-related factor 2 (Nrf2), while downregulating pro-apoptotic genes like Bcl-2-associated X protein (Bax) and Caspase-3. These findings suggest that HFPS exerts its antioxidant effects by modulating the Nrf2/HO-1 pathway and redox homeostasis.

Discussion

This study contributes to the understanding of the structure-function relationships and antioxidant mechanisms of HFPS, highlighting its potential applications as a natural antioxidant in various fields.