Understanding and recognizing the structural characteristics of lignin-carbohydrate complexes (LCCs) and lignin in different growth stages and tissue types of bamboo will facilitate industrial processes and practical applications of bamboo biomass. Herein, the LCC and lignin samples were sequentially isolated from fibers and parenchyma cells of bamboo with different growth ages. The diverse yields of sequential fractions not only reflect the different biomass recalcitrance between bamboo fibers and parenchyma cells but also uncover the structural heterogeneity of these tissues at different growth stages. The molecular structures and structural inhomogeneities of the isolated lignin and LCC samples were comprehensively investigated. The results showed that the structural features of lignin and LCC linkages in parenchyma cells were abundant in β-O-4 linkages but less with carbon-carbon linkages, suggesting that lignin and cross-linked LCC in parenchyma cells are simple in nature and easily to be tamed and tractable in the current biorefinery. Parallelly, the different ball-milled samples were directly characterized by high-resolution (800 M) solution-state 2D-HSQC NMR to analyze the whole lignocellulosic material. Overall, the scheme presented in this study will provide a comprehensive understanding of lignin and LCC linkages in fibers and parenchyma cells of bamboo and enable the utilization of bamboo biomass.

Lotus (Nelumbo nucifera), belonging to the family of Nelumbonaceae, is a beautiful aquatic perennial plant. It has been used as an ancient horticulture plant and famous agricultural crop for thousands of years. Modern phytochemical and pharmacological experiments have proved that polysaccharide is one of the most pivotal bioactive constituents of lotus. Hence, the systematic review covering the fundamental research advances and developing prospects of N. nucifera polysaccharides (NNPs) is an urgent demand to provide theoretical basis for their further research and application. The present review summarizes current emerging research progresses on the polysaccharides isolated from lotus, and it focuses on advanced extraction and purification methods, unique structural features, engaging biological activities, potential molecular mechanisms, as well as the relationship of structure and activity of NNPs. This review sheds light on the potential values of NNPs in affording functionally bioactive agents in food industry or therapeutically effective medicines for health care. In addition, this review will provide valuable insights for further commercial product development and promising industrial application of NNPs in both of the fundamental research communities and food or pharmaceutical industries in future.

The mechanisms of trypsin hydrolysis time on the structure of soy protein hydrolysate fibril aggregates (SPHFAs) and the stability of SPHFAs-high internal phase Pickering emulsions (HIPPEs) were investigated. SPHFAs were prepared using soy protein hydrolysate (SPH) with different trypsin hydrolysis time (0 min-120 min) to stabilize SPHFAs-HIPPEs. The results showed that moderate trypsin hydrolysis (30 min, hydrolysis degree of 2.31 %) induced SPH unfolding and increased the surface hydrophobicity of SPH, thereby promoting the formation of flexible SPHFAs with maximal thioflavin T intensity and ζ-potential. Moreover, moderate trypsin hydrolysis improved the viscoelasticity of SPHFAs-HIPPEs, and SPHFAs-HIPPEs remained stable after storage at 25 °C for 80 d and heating at 100 °C for 1 h. Excessive trypsin hydrolysis (> 30 min) decreased the stability of SPHFAs-HIPPEs. In conclusion, moderate trypsin hydrolysis promoted the formation of flexible SPHFAs with high surface charge by inducing SPH unfolding, thereby promoting the stability of SPHFAs-HIPPEs.

This study aimed to examine the changes in the structural characterization of cross-linked tapioca treated with sodium trimetaphosphate(STMP). The degree of substitution in the cross-linked starch was determined by the iodine absorption method. Scanning electron microscopy, particle size measurement, Fourier-transform infrared spectroscopy (FT-IR), and x-ray diffraction (XRD) were used to characterize the structure of modified tapioca starch at different substitution degrees. The results demonstrated that the degree of substitution of cross-linked starch increased with the increase in the amount of the cross-linking agent. The modified starch particles aggregated to form a mass structure, but the average particle size did not change with the cross-linker content and was about 17 μm. FT-IR and XRD experiments showed that the cross-linking esterification of starch with sodium trimetaphosphate generated new phosphate groups, increasing the content of phosphoric acid in starch, and the A-type crystalline structure of starch was not changed.

The by-product of deer skin, which has mostly been used as a decorative material, is rich in collagen and amino acids that could bind to Ca2+. Therefore, the preparation process, stability, antioxidant activity and calcium transport capacity of deer skin collagen peptide calcium chelate (Ca-DSCP) were investigated. In addition, the structure of the new chelate was characterized. The preparation process of Ca-DSCP was optimized using one-way experiments and response surface methodology. The ideal conditions were pH 9, 48 °C, and a peptide-to-calcium mass ratio of 5:1. The chelation rate was (60.73 ± 1.54)%. Zeta potential, XRD, UV-vis and FTIR analyses yielded that deer skin collagen peptides (DSCP) underwent a chelating reaction with calcium ions to form new structures. The stability of Ca-DSCP and the fraction of bioavailability of calcium ions were determined using in vitro gastrointestinal digestion and a Caco-2 cell monolayer model. The results showed that fraction of bioavailability and stability of DSCP were improved by influencing the structural characterization. The antioxidant activities of DSCP and Ca-DSCP were evaluated by measuring relevant oxidative stress indicators, DPPH radical scavenging capacity and hydroxyl radical scavenging capacity. Finally, bioinformatics and molecular docking techniques were utilized to screen and study the antioxidant mechanism of DSCP.

This study isolated a novel peptide MMGGED with strong calcium-binding capacity from defatted walnut meal and synthesized a novel peptide‑calcium chelate COS-MMGGED-Ca with high stability via glycation. Structural characterization and computer simulation identified binding sites, while in vitro digestion stability and calcium transport experiments explored the chelate\'s properties. Results showed that after glycation, COS-MMGGED bound Ca2+ with 88.75 ± 1.75 %, mainly via aspartic and glutamic acids. COS-MMGGED-Ca released Ca2+ steadily (60.27 %), with thermal denaturation temperature increased by 18 °C and 37 °C compared to MMGGED-Ca, indicating good processing performance. Furthermore, COS-MMGGED significantly enhanced Ca2+ transport across Caco-2 monolayers, 1.13-fold and 1.62-fold higher than CaCl2 and MMGGED, respectively, at 240 h. These findings prove glycation enhances structural properties, stability, calcium loading, and transport of peptide‑calcium chelates, providing a scientific basis for developing novel efficient calcium supplements and high-value utilization of walnut meal.

Carrageenans were widely utilized as thickening and gelling agents in the food and cosmetic industries, and their oligosaccharides have been proven to possess enhanced physicochemical and biological properties. In this study, Shewanella sp. LE8 was utilized for the depolymerization of κ-, ι-, and λ-carrageenan under conditions of fermentation. During a 24-h fermentation at 28 °C, the apparent viscosity of κ-, ι-, and λ-carrageenan decreased by 53.12%, 84.10%, and 59.33%, respectively, accompanied by a decrease in storage modulus, and loss modulus. After a 72-h fermentation, the analysis of methylene blue and molecular weight distribution revealed that ι-carrageenan was extensively depolymerized into smaller polysaccharides by Shewanella sp. LE8, while exhibiting partial degradation on κ- and λ-carrageenan. However, the impact of Shewanella sp. LE8 on total sugars was found to be limited; nevertheless, a significant increase in reduced sugar content was observed. The ESIMS analysis results revealed that the purified components obtained through ι-carrageenan fermentation for 72 h were identified as tetrasaccharides, while the two purified components derived from λ-carrageenan fermentation consisted of a hexasaccharide and a tetrasaccharide, respectively. Overall, the present study first reported the depolymerization of ι-and λ-carrageenan by Shewanella and suggested that the Shewanella could be used to depolymerize multiple carrageenans, as well as complex polysaccharides derived from red algae, to further obtain their oligosaccharides.

The aim of this study was to prepare and characterize jellyfish collagen peptide (JCP)-calcium chelates (JCP-Ca) using peptides with different molecular weights. Further analysis revealed that the low-molecular-weight jellyfish collagen peptide (JCP1) had a higher chelation rate. Structural characterization showed that functional groups such as N-H, C[bond, double bond]O, and -COO were involved in the formation of JCP-Ca, which shifted towards a more ordered and regular structure, and smaller-molecular-weight peptides were more likely to form a denser structure. In addition, JCPs chelated with calcium ions showed excellent antioxidant capacity. JCP-Ca showed good stability in heat-treated and gastrointestinal environments, whereas the antioxidant activity was significantly reduced under highly acidic conditions. The present study addresses the knowledge gap regarding the physicochemical properties of JCP-Ca and establishes a solid research foundation for its associated products.

Thaumatin-like proteins (TLP), existing in various fruits, have allergenic and pro-inflammatory activities. The current research attempts to reduce the pro-inflammatory activity of litchi TLP (LcTLP) through high hydrostatic pressure (HHP). This study demonstrated that HHP (250-500 MPa, 5-10 min) was a potential technique to reduce the pro-inflammatory activity of LcTLP, which was attributed to the irreversible destruction of the active domain, ie., V-cleft. SDS-PAGE showed no change in the protein profile. Continuous HHP treatment promoted LcTLP unfolding and then reassembling (400 MPa was the transition pressure), and the content of β-sheets decreased from 35.4% to 31.1%. HHP treatment could mitigate inflammatory responses of LcTLP, as confirmed by ELISA and western blot. Molecular dynamics simulations showed significant changes in the residue network under HHP, thereby affecting the V-cleft. These findings provide a theoretical explanation and structural insights into the HHP-induced reduction of pro-inflammatory activity of LcTLP.

The structural and multiferroic properties of xNi0.24Zn0.58Cu0.18Fe2O4(NZCFO)-(1-x)Bi0.9Nd0.1Fe0.95 Sc0.05O3(BNFSO) are explored in this paper. Bi2O3 additives significantly lower the sintering temperature of the composites. The XRD analysis validates the coexistence of hexagonal perovskite BNFSO and spinel NZCFO phases. The FESEM images illustrate an almost homogeneous amalgamation of the BNFSO and NZCFO grains. The real part of initial permeability and the relative quality factor increases with NZCFO contents in the composites. The maximum permeability is observed for the composite with 80 % ferrite content. The ferroelectric BNFSO exhibits antiferromagnetic behavior and with the increase in NZCFO the saturation magnetization increases significantly. The dielectric constant confirms typical dielectric dispersion at low frequencies because of Maxwell-Wagner space charge polarization. The P-E hysteresis measurement reveals that the composite with 40 % ferrite content exhibits the highest loop area and hence a large energy storage capacity. Incorporating BNFSO and NZCFO into the composite boosts the multiferroic properties, which might be a suitable alternative to single-phase multiferroics.