Pectin demethylation-mediated cell wall Na+ retention positively regulates salt stress tolerance in oilseed rape.

KEY MESSAGE: Integrated phenomics, ionomics, genomics, transcriptomics, and functional analyses present novel insights into the role of pectin demethylation-mediated cell wall Na+ retention in positively regulating salt tolerance in oilseed rape. Genetic variations in salt stress tolerance identified in rapeseed genotypes highlight the complicated regulatory mechanisms. Westar is ubiquitously used as a transgenic receptor cultivar, while ZS11 is widely grown as a high-production and good-quality cultivar. In this study, Westar was found to outperform ZS11 under salt stress. Through cell component isolation, non-invasive micro-test, X-ray energy spectrum analysis, and ionomic profile characterization, pectin demethylation-mediated cell wall Na+ retention was proposed to be a major regulator responsible for differential salt tolerance between Westar and ZS11. Integrated analyses of genome-wide DNA variations, differential expression profiling, and gene co-expression networks identified BnaC9.PME47, encoding a pectin methylesterase, as a positive regulator conferring salt tolerance in rapeseed. BnaC9.PME47, located in two reported QTL regions for salt tolerance, was strongly induced by salt stress and localized on the cell wall. Natural variation of the promoter regions conferred higher expression of BnaC9.PME47 in Westar than in several salt-sensitive rapeseed genotypes. Loss of function of AtPME47 resulted in the hypersensitivity of Arabidopsis plants to salt stress. The integrated multiomics analyses revealed novel insights into pectin demethylation-mediated cell wall Na+ retention in regulating differential salt tolerance in allotetraploid rapeseed genotypes. Furthermore, these analyses have provided key information regarding the rapid dissection of quantitative trait genes responsible for nutrient stress tolerance in plant species with complex genomes.

Effects of fecal microbiota transplantation and fecal virome transplantation on LPS-induced intestinal injury in broilers.

The interesting roles and efficiencies of fecal microbiota transplantation (FMT) have attracted considerable attention and have been gradually evidenced in specific animal models. While the growing evidence that bacteriophages play roles in FMT efficacy has attracted considerable interest. In this study, we aimed to explore the effects of FMT and fecal virome transplantation (FVT) in improving inflammatory damage and ileal microbiota disorder in broilers. A total of 224 Arbor Acres broilers were selected at 1-day-old and randomly divided into the following 4 groups, with 56 broilers in each group: the CON group (the negative control group, sterile physiological saline injection + sterile phosphate-buffered saline (PBS) solution gavage), LPS group (the positive control group, lipopolysaccharide (LPS) injection + sterile PBS solution gavage), LPS + FMT group (LPS injection + FMT solution gavage), LPS + FVT group (LPS injection + FVT solution gavage). The results showed that: LPS injection significantly upregulated the mRNA expression levels of IFN-γ (P < 0.05) and IL-8 (P < 0.001) in ileal mucosa of broilers at 11th day of age (D11), while LPS + FMT and LPS + FVT did not; LPS injection significantly upregulated the mRNA expression of ZO-1 in ileal mucosa at D11 (P < 0.01), while LPS + FMT and LPS + FVT did not; at D11, compare to CON group, LPS injection and LPS + FMT significantly increased the relative abundance of virulence factor Rab2 interacting conserved protein A-related genes in broiler ileum contents (P < 0.05), while LPS + FVT had no significant difference with CON group (P > 0.05); at D11, LPS injection significantly downregulated the biosynthesis of antibiotics pathway (P < 0.05) in the ileal contents, while LPS + FVT did not. In conclusion, both FMT and FVT could promote the recovery of inflammation caused by LPS. Furthermore, FVT had shown less disadvantage stimulation on the broilers and could reduce the risk of transmission of pathogenic genes, compared to FMT.

The synergistic effect of epigallocatechin-3-gallate and quercetin co-loaded hydrogel beads on inflammatory bowel disease.

The synergistic effect of epigallocatechin-3-gallate (E) and quercetin (Q) enhances the therapeutic efficacy on related diseases; however, the instability and lower bioavailability of E and Q limited their application. Therefore, E and Q were co-encapsulated in hydrogel beads (H) with sodium alginate (SA) and soybean protein isolate (SPI) to improve their stability and bioavailability. The anti-inflammatory effect and molecular mechanism of action of E and Q co-loaded H in inflammatory bowel disease (IBD) were also investigated. The results showed that EQH-treated macrophages produced the lowest NO and TNF-α at 18.64 µmol L-1 and 5855.25 ng mL-1, respectively. The protein expression of p-NF κB-p65 was the lowest in EQH, indicating that EQH inhibits the activation of the pro-inflammatory NF-κB signaling pathway. The colon length of IBD model rats fed EH, QH, and EQH increased; histological analysis revealed intact layers of colonic epithelial cells with no observable tissue damage. The TNF-α and IL-1ß levels in the plasma of the EQH-treated rats decreased, indicating the inhibition of the TLR4 and NF-κB signaling pathways, and Q's level in the colon was the highest at 0.04 mg mL-1. This study provides a theoretical basis for the application of E and Q in IBD.

Development of immobilized beta1-adrenoceptor chromatography for rapid discovery of ligands specifically binding to the receptor from herbal extract.

The discovery of beta1-adrenoceptor (ß1-AR) ligands is viewed as an enormous demand for fighting ailments mediated by the receptor including cardiovascular diseases. Such pursuit is gravely challenged due to the lack of lead screening methods with high efficiency. This work developed a chromatographic method for pursuing ß1-AR ligand from the herbal extract by fusing epidermal growth factor receptor (EGFR) as a tag at its C-terminus to stably express the fusion receptor in E. coli, immobilizing the expressed EGFR-tagged ß1-AR onto ibrutinib-derivatized amino microspheres, and applying the immobilized receptor in the analysis of ligand-receptor interaction and herbal extract. Comprehensive characterizations like X-ray photoelectron spectroscopy and retention behaviors of canonical drugs demonstrated high specificity and good stability of the immobilized ß1-AR prepared through the covalent reaction between the EGFR and ibrutinib decorated on the microsphere surface. Frontal analysis of atenolol, metoprolol, and esmolol confirmed their bindings to ß1-AR with association constants of 1.07 × 104, 6.54 × 103, and 1.45 × 104 M-1. The thermodynamic analysis provided proof of electrostatic interaction, hydrogen bonds, and van der Waals force driving those interactions. Pulegone was recognized as a bioactive compound that specifically binding to ß1-AR from the extract of Ziziphora clinopodioides Lam by analyzing the retention peak through reverse-phase high performance liquid chromatography coupled with tandem mass spectrometry. These results, taken together, indicated that the current method is possible to provide an alternative for discovering ß1-AR ligands with high efficiency from complex matrices like herbal extract.

Oppositely Charged Pickering Emulsion Co-Stabilized by Chitin Nanoparticles and Fucoidan: Influence of Environmental Stresses on Stability and Antioxidant Activity.

Single emulsifiers exhibit varying degrees of restriction in stabilizing emulsions. Oppositely charged chitin nanoparticles and fucoidan complex particles were used as emulsifiers to stabilize a o/w Pickering emulsion and explore its stability and antioxidant activity under different environmental stresses. The results showed that the emulsion with the smallest mean particle size (1.02 µm) and strongest zeta potential (-29.3 mV) was formed at pH 7. Moreover, at this pH, it presented the highest physical stability and antioxidant activity and the lowest emulsion creaming index. The investigation of the effect of temperature on the stability and antioxidant activity of the emulsion revealed that, after freezing/thawing at -20 °C, the emulsion was unstable, the particle size increased, and the stability and antioxidant activity were low. In contrast, the emulsions treated at 25, 37, and 60 °C displayed no significant differences and exhibited high stabilities and antioxidant activities. Additionally, increasing the salt ion concentration further decreased the emulsion stability and antioxidant activity. Particularly, the emulsion with a salt concentration of 500 mM displayed the lowest stability, and stratification occurred after 30 d of storage. The Pickering emulsion remained stable under different environmental stresses expect for at a temperature of -20 °C and 500 mM salt ion concentration.

Development of high-internal-phase emulsions stabilized by soy protein isolate-dextran complex for the delivery of quercetin.

BACKGROUND: Protein-polysaccharide complexes have been widely used to stabilize high-internal-phase emulsion (HIPEs). However, it is still unknown whether soy protein isolate-dextran (SPI-Dex) complexes can stabilize HIPEs or what is the effect of Dex concentration on the HIPEs. Furthermore, the non-covalent interaction mechanism between SPI and Dex is also unclear. Therefore, we fabricated SPI-Dex complexes and used them to stabilize HIPEs-loaded quercetin and explore the interaction mechanism between SPI and Dex, as well as the effect of Dex concentration on the particle size, ζ-potential, microstructure, rheology, quercetin encapsulation efficiency, and gastrointestinal fate of the HIPEs. RESULTS: Spectral analysis (fourier transform infrared spectroscopy, ultraviolet spectroscopy, and fluorescence spectroscopy) results identified the formation of SPI-Dex complexes, and indicated that the addition of Dex changed the spatial structure of SPI, whereas thermodynamic analysis (ΔH > 0, ΔS > 0) showed that hydrophobic interactions were the main driving forces in the formation of SPI-Dex complexes. Compared with HIPEs stabilized by SPI, the SPI-Dex complex-stabilized HIPEs had smaller particles (3000.33 ± 201.22 nm), as well as higher ζ-potential (-21.73 ± 1.10 mV), apparent viscosities, modulus, and quercetin encapsulation efficiency (98.19 ± 0.14%). In addition, in vitro digestion revealed that SPI-Dex complex-stabilized HIPEs significantly reduced the release of free fatty acid and improved quercetin bioaccessibility. CONCLUSION: HIPEs stabilized by SPI-Dex complexes delayed the release of free fat acid and improved the bioaccessibility of quercetin, and may be help in designing delivery systems for bioactive substances with specific properties. © 2022 Society of Chemical Industry.

Emulsions co-stabilized by soy protein nanoparticles and tea saponin: Physical stability, rheological properties, oxidative stability, and lipid digestion.

Herein, the effects of the concentration (0.1%-1.0%, w/v) and addition sequence of tea saponin (TS) on the physical stability, oxidative stability, rheological properties, and in vitro digestion of the emulsions stabilized by heat-induced soy protein isolate nanoparticles (SPs) were investigated. The results revealed that the concentration and addition sequence of TS have significant impact on the microstructure, stability, rheological properties, and in vitro digestion of the emulsions. TS was shown to not only fill the interfacial gaps but also adsorb on the particle surfaces, contributing to interfacial wettability. With increasing TS concentration, interfacial tension decay is clearly observed. Further, TS endows the droplets with electrostatic repulsion and steric resistance, preventing their flocculation, coalescence, and oxidation. Finally, in vitro digestion experiments demonstrated that the presence of TS delayed the lipid digestion of the emulsions.

Whey protein isolate-phytosterols nanoparticles: Preparation, characterization, and stabilized food-grade pickering emulsions.

The preparation of whey protein isolate (WPI) particles by heat induction usually reduces both protein nutritional value and functionality. In this study, WPI and phytosterols (PSs) were used to prepare whey protein isolate-phytosterol (WPS) nanoparticles as stabilizers of oil-in-water Pickering emulsions, and the effects of PSs on the structure and function of the nanoparticles were studied. The results showed that the WPI and PSs combine through non-covalent bonding, which alters the nanoparticle structure and function. When the WPI/PSs mass ratio was 25:2, the nanoparticles (WPS-4) exhibited excellent interfacial wettability, emulsification stability, and antioxidant activity. The nanoparticles formed thick and dense interfacial films on the droplet surfaces to protect them, and the emulsion stabilized with the WPS-4 nanoparticles exhibited the best storage stability and oxidation stability. The emulsion can also reduce the digestion of lipids. These results provide a theoretical basis for the application of WPS nanoparticles.

Co-encapsulation of (-)-epigallocatechin-3-gallate and quercetin in double emulsion hydrogel beads: Microstructures, functional properties, and digestion behaviors.

Co-loaded (-)-epigallocatechin-3-gallate (EGCG) and quercetin double emulsions and hydrogel beads were prepared, and their structure, functions, and digestion characteristics were investigated. The double emulsion particles were adsorbed by the cross-linked chains of the hydrogel beads. The encapsulation efficiencies of EGCG and quercetin within the hydrogel beads were higher than those within the double emulsion, while the antioxidant activities of the double emulsions were higher than those of the hydrogel beads. A lower amount of free fatty acids (FFAs) was released from the hydrogel beads than that released from the double emulsions. The bioavailability of EGCG was higher in the hydrogel beads than those in the double emulsions, while the quercetin bioavailability was not significantly different expect for the ratio of 3:7. The hydrogel beads remained intact in the stomach; however, numerous oil spills occurred in the small intestine. These data may improve double-emulsion-based delivery systems for controlled lipolysis and the release of co-encapsulated hydrophilic and lipophilic bioactive compounds.

Sodium alginate/soybean protein-epigallocatechin-3-gallate conjugate hydrogel beads: evaluation of structural, physical, and functional properties.

Sodium alginate (SA) hydrogel beads have been extensively studied as delivery systems for bioactive compounds. Key challenges include overcoming the highly porous and poor emulsifying properties of SA hydrogels. Herein, soy protein isolate (SPI) was modified by covalent and noncovalent conjugation with epigallocatechin-3-gallate (EGCG), followed by complexation with SA to change the SA structure and fabricate hydrogel beads with low porosities. Microencapsulation beads were fabricated from SA-, SA/SPI-, and SA/SPI-modified EGCG complexes with a corn oil/quercetin mixture core. After the covalent and noncovalent SPI-modified EGCG complexes were combined with SA, the OH stretching vibration shifted, indicating that hydrogen bonds formed between the protein and SA, and the crystal structure of SA was destroyed. To achieve crosslinking, the beads were injected into a CaCl2 solution, whereby Ca2+ ions replaced the Na+ ions in SA. Meanwhile, the addition of covalent and noncovalent SPI-modified EGCG complexes promoted the binding capacity of Ca2+ and SA. All hydrogel beads possessed open-cell microstructures with interconnecting pores. The SA/SPI-modified EGCG hydrogel beads exhibited smoother surfaces, thicker shells, and lower porosity than the SA hydrogel beads. Moreover, they exhibited significantly higher antioxidant activities. During digestion, all types of hydrogel bead maintained their structure, and only a small part of the encapsulated oil and quercetin was digested in the upper part of the gastrointestinal tract. In short, the formation mechanism of hydrogel beads was clarified, and hydrogel beads with low porosity and high antioxidation activities were successfully fabricated.

Molecular crowding prevents the aggregation of protein-dextran conjugate by inducing structural changes, improves its functional properties, and stabilizes it in nanoemulsions.

In most of the recent research on emulsions related to food products containing protein-polysaccharide interactions established via the Maillard reaction have been used as emulsifiers. Key challenges in such studies include long reaction times, uncontrollable extent of reaction, and protein denaturation and aggregation. The living cell is inherently crowded molecularly with biomacromolecules, occupying 20-40% of the total volume. In this study, to mimic cellular crowding conditions, we have used polyethylene glycol as a chemical crowding agent. The degree of glycation and the results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) indicated that a crowding environment triggers glycosylation and that the glycosylation degree gradually increases (p < 0.05) with increasing PEG concentration, which shortens the reaction time. The surface hydrophobicity of soybean protein isolate (SPI) significant decreased (p < 0.05), and the protein structure gradually unfolded from a helix to a random coil to prevent aggregation of SPI in the crowded environment. The solubility and the emulsifying and antioxidant properties improved upon adding the crowding reagent PEG. The chemical, freeze-thaw, and thermal stabilities of the nanoemulsion-stabilized SPI-dextran conjugate improved with increasing PEG concentration. However, the crowding environment had no effect on the salt stability of nanoemulsions.