The decreased interface tension increased the transmembrane transport of soy hull polysaccharide-derived SCFAs in the Caco-2 cells.

Polysaccharides impact intestinal fermentation and regulate interfacial properties which affect absorption and transportation. Short-chain fatty acids (SCFAs), the main metabolites of soy hull polysaccharide lysate, are readily absorbed by the body and perform various physiological functions. We analysed the interfacial properties and transport of soy hull polysaccharide-derived SCFAs in the Caco-2 cell model to clarify the transmembrane transport mechanism. The results showed that the interfacial properties of the co-culture system were influenced by both transit time and concentration of SCFAs, the uptake and transit rates of SCFAs at 1-3 h increased significantly with time (P < 0.05). With increasing transit time and concentration, the transit rates of SCFAs on the apical side (AP) â†’ basolateral side (BL) and BL â†’ AP sides increased and then stabilised, the transit rate of the AP â†’ BL side was higher than that of the BL â†’ AP side. Proteomic analysis showed that soy hull polysaccharide-derived SCFAs resulted in the differential expression of 285 upregulated and 501 downregulated after translocation across Caco-2 cells. The differentially expressed proteins were mainly enriched in ribosomes, oxidative phosphorylation, nuclear transport, and SNARE vesicular transport. This study lays the theoretical foundation for understanding the structure-activity relationship of soy hull polysaccharides in the intestine.

Pulsed light treatment enhances starch hydrolysis and improves starch physicochemical properties of germinated brown rice.

BACKGROUND: Recently, germinated brown rice (GBR) has gained substantial attention as a functional food because of its nutritional attributes. Notably, pulsed light technology (PLT) has emerged as a promising tool for enhancing rice germination and, consequently, has improved the nutritional and functional qualities of GBR-derived products. However, further research is required to comprehensively understand the impact of PLT on GBR physicochemical properties. The present study aimed to investigate the stimulating effects of PLT on starch hydrolysis, starch structure and functional properties of GBR. RESULTS: The PLT substantially boosted α-amylase activity during brown rice germination, leading to a 10.9% reduction in total starch content and a 17.3% increase in reducing sugar content, accompanied by elevated free water levels. Structural analysis indicated no changes in starch crystalline types, whereas gelatinization temperature slightly increased. Pasting properties exhibited a significant drop in peak viscosity. Scanning electron microscopy showed surface erosion of starch granules with microstructural changes. Furthermore, correlation analysis established positive links between α-amylase activity, reducing sugar accumulation, starch structure and functional properties in GBR. CONCLUSION: The present study demonstrates that PLT enhanced the physicochemical properties of GBR starch, significantly improving the stability of GBR products, thereby contributing to expanded applicability of rice starch in the food industry. © 2023 Society of Chemical Industry.

Application of soybean isolate protein (SPI) and soy hull polysaccharide (SHP) complex in fermentation products.

We investigated the stability of a soy protein isolate (SPI)/soy hull polysaccharide (SHP) composite and its effect on the quality of fermented products. Sonication contributed to a more stable SPI/SHP composite. Increasing SHP concentrations increased the viscoelasticity of the emulsions and decreased turbiscan stability index (TSI) values, indicating that SHP improved the emulsification and stability of the composite emulsions. The fermented products with SHP had an increased ability to bind to water. Hardness, gelling, chewiness, sourness, and astringency increased with polysaccharide addition. Additionally, SHP promoted acid production by lactic acid bacteria during storage. All groups had viscoelastic behavior (G' ˃ G″, tan δ < 1), with viscosity increasing and subsequently decreasing. TSI values were significantly lower in the treated groups than in the control group. The results revealed that SHP improved the sensory quality and storage stability of fermented products.

Storage stability and interfacial rheology analysis of high-internal-phase emulsions stabilized by soy hull polysaccharide.

High-internal-phase emulsions (HIPEs) are more promising candidates for development to replace hydrogenated fatty acids, yet the current HIPEs are limited for stabilizers require very high surface activity. This study showed that HIPEs could be prepared with 1.0-2.2 wt% soy hull polysaccharide (SHP) and the related stability indicators of HIPEs were analyzed. The plasticity, stress resistance, stability of the HIPEs were positively correlated with the SHP content. The interfacial adsorption experiments showed that SHP had the good ability to reduce interfacial tension and formed an elastic interfacial layer. Dilatational rheological results showed the interfacial film reached jammed saturation at about 1.8 wt% of SHP concentration, and the zeta potential results were consistent. This study demonstrated that SHP was an efficient stabilizer of HIPEs, which was useful both for the preparation of HIPEs and for developing uses for SHP.

Effect of soluble soybean polysaccharides on the short- and long-term retrogradation properties of instant rice.

BACKGROUND: Rice starch retrogradation is prone to occur during instant rice storage, which contributes to reduced viscosity, poor sensory characteristics, and shortened shelf life. The purpose of this study was to explore the anti-retrogradation effect of soybean soluble polysaccharides (SSPS) on instant rice and the possible interaction between SSPS and high-moisture starch products. RESULTS: We studied the effects of SSPS on the retrogradation of instant rice, using hardness as an index. The optimal amount of SSPS was 0.2%. Hardness, enthalpy, relative crystallinity, and full width at half maximum values were lower in the SSPS-treated group than in the control group (no SSPS) during storage. The weight loss rate of instant rice had the following trend: SSPS-treated group (0 day) < control group (0 day) < SSPS-treated group (28 days) < control group (28 days). The lower the weight loss rate, the lower was the material loss. Scanning electron microscopy results showed that the gaps between starch granules were less obvious in the control group than in the SSPS-treated group during storage. The SSPS-treated group presented a starch network with uniform chambers. SSPS might compete with starch molecules for water absorption, thereby improving water retention and limiting starch retrogradation. CONCLUSION: The results showed that adding SSPS to instant rice could effectively inhibit starch retrogradation, because the interaction of SSPS and amylopectin side chains inhibited the crosslinking of starch molecules through hydrogen bonds, which hindered the formation of ordered structures. It was helpful to understand the anti-retrogradation mechanism of SSPS during the storage of instant rice, and provided the basis for the industrial production of high-water-content starch foods. © 2023 Society of Chemical Industry.

Characterization of enzymatic cross-linking soy protein isolate xerogels and its shape memory effect induced by ethylcellulose.

In this study, the deformation behavior of soybean protein isolate (SPI) xerogels cross-linked with different transglutaminase (TGase) concentrations was investigated. The gel properties of TGase cross-linked SPI were analyzed by rheology and texture. Results showed that 0.4% TGase completely promoted the intermolecular cross-linking, SPI molecules had more binding sites and α-helix content and less irregular curl structure. The presence of 0.4% TGase enhanced the water binding ability and thermal stability of SPI xerogel, and its denaturation temperature was up to 181.50 °C. The corresponding texture characteristics showed that hardness and elasticity were significantly increased by 182.90% and 25.00%, respectively. Results showed that SPI containing 0.4% TGase had the best 3D (three-dimension) shape change after hydration. However, excessive TGase (1.0% w/v) led to excessive lysine covalent cross-linking, which increases the porosity of the gel surface, causing the disrupted gel network. The research provides insights and new ideas for food-processing technology called 4D (four-dimension) food.

Mytilus farming drives higher local bacterial diversity and facilitates the accumulation of aerobic anoxygenic photoheterotrophic related genera.

Research to assess the impacts of mariculture on the microbiota of the surrounding environment is still inadequate. Here, we examined the effects of Mytilus coruscus farming on the diversity of bacterial community in surrounding seawater using field investigations and indoor simulations, focusing on the variation of members of aerobic anoxygenic photoheterotrophic (AAP) bacteria. In the field, Mytilus farming shaped bacterial community and significantly increased their diversity, including biomass, OTUs, Shannon, relative abundance, number of enriched species, as compared with the non-farming area. Higher abundance of AAP related genera was observed in the Mytilus farming seawater. Under the controlled condition, the presence of M. coruscus significantly shaped the bacterial community composition and caused species composition to become similar after 10 days. Furthermore, the presence of M. coruscus consistently strengthened local diversity in seawater bacterial community, with linkages to the recruitment of AAP members as well. In addition, the tissue-related composition of M. coruscus significantly differed from those in seawater. Our findings highlight a ecological importance of Mytilus farming, as process that shape surrounding water-cultured bacterial community and offer experimental evidence for the accumulation of AAP-related genera in aquaculture systems.

Application of soy protein isolate fiber and soy soluble polysaccharide non-covalent complex: A potential way for pH-triggered release.

The non-covalent interactions between protein and polysaccharide have the potential to design responsive materials. In this study, soy protein isolate fiber/soy soluble polysaccharide (SPIF/SSPS) non-covalent complex was used to create an emulsion, and the pH-response performance was evaluated by investigating their microstructure, interfacial properties, and stability at pH values of 2.0-10.0. The SPIF/SSPS complex was relatively stable at pH 2.0 and 4.0, and the corresponding emulsions had uniform droplets that showed outstanding storage stability after 21 days. However, the SPIF/SSPS complex was dissociated gradually with the elevation of pH, especially under alkaline condition, that caused the flocculation and coalescence in emulsion. This phenomenon not only relate to electrostatic repulsion, but also relate to the disintegration of SPIF. Furthermore, the encapsulated curcumin is released rapidly from emulsion when the pH increased above 6.0. This research may provide an outstanding pH-response strategy that have the potential for pH-triggered release.

Effects of different enzyme extraction methods on the properties and prebiotic activity of soybean hull polysaccharides.

In this study, five different processes, including hot water (HW-ASP), single enzyme (cellulase, pectinase and papain; C-ASP, PE-ASP, and P-ASP), and compound-enzyme (cellulose: pectinase: papain = 3:3:1; CE-ASP) for the extraction of soybean hull polysaccharides (ASPs) were employed, and the characterization and prebiotics activity of five polysaccharides were analyzed. These polysaccharides possessed different primary structural characteristics, including molecular weight distribution, monosaccharide composition, chemical composition, surface morphology, potential particle size, etc., while similar functional groups. In vitro digestibility assay indicated that C-ASP had strong resistance to gastric juice hydrolysis and α-amylase as compared with HW-ASP. Furthermore, C-ASP elevated the acidifying activity and promoted the growth of probiotics (Lactobacillus paracasei, Lactobacillus rhamnosus, and Lactobacillus acidophilus) during the fermentation (p < 0.05). C-ASP improved the levels of total short-chain fatty acids (SCFAs) and had better prebiotic activity than HW-ASP (p < 0.05). These findings denote that enzyme-assisted polysaccharides extracted from soybean hulls have the potential to be served as novel probiotics.

Soy glycinin-soyasaponin mixtures at oil-water interface: Interfacial behavior and O/W emulsion stability.

Soy glycinin (11S) was mixed with soyasaponin (Ssa) to elucidate the mechanism(s) involved in the stabilization of emulsions by mixed systems based on dynamic interfacial tension and dilatational rheology at the oil-water interface. The short/long-term properties of oil-in-water emulsions stabilized by 11S-Ssa mixtures included droplet-size distribution, droplet ζ-potential, microstructure, and Turbiscan stability index. The combination of Ssa (0.05%) with 11S significantly affected the interfacial dilatational and emulsion properties although the interfacial properties were still dominated by the protein. Higher concentrations (0.1% and 0.2%) of Ssa combined with 11S synergistically decreased the interfacial tension, which was attributed to the interaction between 11S and Ssa. Using high Ssa concentrations (0.25%-0.5%) enhanced the long-term stability of emulsions (in response to external deformations) after 42 d. These results will aid the basic understanding of protein-Ssa interfacial adsorption during emulsion formation and can help prepare natural food additives for designing emulsions.

Contribution of soybean polysaccharides in digestion of oil-in-water emulsion-based delivery system in an in vitro gastric environment.

This study aims to evaluate the effects of soy soluble polysaccharide and soy hull polysaccharide on stability and characteristics of emulsions stabilised by soy protein isolate in an in vitro gastric environment. Zeta potential and particle size were used to investigate the changes of physico-chemical and stability in the three emulsions during in vitro gastric digestion, following the order: soy protein isolate-stability emulsion < soy protein isolate-soy soluble polysaccharide -stability emulsion < soy protein isolate-soy hull polysaccharide-stability emulsion, confirming that coalescence in the soy protein isolate-stability emulsion occurred during in vitro gastric digestion. Optical microscopy and stability measurement (backscattering) also validate that addition of polysaccharide (soy soluble polysaccharide and soy hull polysaccharide) can reduce the effect of simulated gastric fluid (i.e., pH, ionic strength and pepsin) on emulsion stability, especially, soy protein isolate-soy hull polysaccharide-stability emulsion, compared with soy protein isolate-stability emulsion. This suggests that the flocculation behaviours of these emulsions in the stomach lead to a difference in the quantity of oil and the size and structure of the oil droplets, which play a significant role in emulsion digestion in the gastrointestinal tract. This work may indicate a potential application of soy hull polysaccharide for the construction of emulsion food delivery systems.

Antimicrobial effect and membrane-active mechanism of tea polyphenols against Serratia marcescens.

In this study, we investigated the antimicrobial effect of tea polyphenols (TP) against Serratia marcescens and examined the related mechanism. Morphology changes of S. marcescens were first observed by transmission electron microscopy after treatment with TP, which indicated that the primary inhibition action of TP was to damage the bacterial cell membranes. The permeability of the outer and inner membrane of S. marcescens dramatically increased after TP treatment, which caused severe disruption of cell membrane, followed by the release of small cellular molecules. Furthermore, a proteomics approach based on two-dimensional gel electrophoresis and MALDI-TOF/TOF MS analysis was used to study the difference of membrane protein expression in the control and TP treatment S. marcescens. The results showed that the expression of some metabolism enzymes and chaperones in TP-treated S. marcescens significantly increased compared to the untreated group, which might result in the metabolic disorder of this bacteria. Taken together, our results first demonstrated that TP had a significant growth inhibition effect on S. marcescens through cell membrane damage.

Effects of sucrose and urea on soy hull pectic polysaccharide gel induced by D-glucono-1,5-lactone.

Gelation properties of pectic polysaccharide extracted with ammonium oxalate from soybean hulls assisted by microwave were seldom studied. Water mobility in soy hull pectic polysaccharide (SHPP) was firstly studied by low field NMR. D-Glucono-1,5-lactone (GDL) and sucrose both could decrease spin-spin relaxation times (T2) of SHPP solutions which indicated the SHPP network formed. Rheological analysis conformed that SHPP gel was formed induced by GDL and enhanced by sucrose. Urea can increase T2 and collapse the network of SHPP. TGA was used to draw the profiles of water desorption from SHPP solutions or gels, during heating at a controlled rate. It was found that sucrose increased the bound water content and urea acted a conversely role. Hydrogen bond is the main force to maintain SHPP gel network.