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In this study, the immunity-enhancing effect of ginger polysaccharides UGP1 and UGP2 on CTX-induced immunosuppressed mice was evaluated. The results showed that ginger polysaccharide could effectively alleviate the symptoms of weight loss and dietary intake reduction induced by CTX, increase fecal water content, reduce fecal pH, and protect immune organs of immunosuppressed mice. In addition, ginger polysaccharides also stimulated the secretion of cytokines IL-2, IL-4, TNF-α and immunoglobulin Ig-G in the serum of mice, increased the expression of Occludin and Claudin-1, and restored the level of short-chain fatty acids in the intestine to improve immune deficiency. Furthermore, ginger polysaccharides significantly reduced the relative abundance ratio of the Firmicutes and Bacteroidetes in mice and increased the relative abundance of Verrucomicrobia and Bacteroidetes at the phylum level. At the family level, ginger polysaccharides increased the relative abundance of beneficial bacteria such as Muribaculaceae , Bacteroidaceae and Lactobacillaceae , and decreased the relative abundance of harmful bacteria such as Rikenellaceae and Lachnospiraceae. Spearman correlation analysis indicated that ginger polysaccharides could enhance intestinal immunity by modulating gut microbiota associated with immune function. These results indicated that ginger polysaccharides have the potential to be a functional food ingredients or a natural medicine for the treatment of intestinal barrier injury. [Display omitted] • The effect of UGPs on immunosuppressive mice was investigated. • UGPs could protect the immune organs of immunosuppressed mice. • UGPs could modulate the structure of gut microbiota associated. • UGPs have the potential for the treatment of intestinal barrier injury. [ABSTRACT FROM AUTHOR]

The emergence of various variants of concern (VOCs) necessitates the development of more efficient vaccines for COVID-19. In this study, we established a rapid and robust production platform for a novel subunit vaccine candidate based on eukaryotic HEK-293 T cells. The immunogenicity of the vaccine candidate was evaluated in pigs. The results demonstrated that the pseudovirus neutralizing antibody (pNAb) titers reached 7751 and 306 for the SARS-CoV-2 Delta and Omicron variants, respectively, after the first boost. Subsequently, pNAb titers further increased to 10,201 and 1350, respectively, after the second boost. Additionally, ELISPOT analysis revealed a robust T-cell response characterized by IFN-γ (171 SFCs/106 cells) and IL-2 (101 SFCs/106 cells) production. Our study demonstrates that a vaccine candidate based on the Delta variant spike protein may provide strong and broad protection against the prototype SARS-CoV-2 and VOCs. Moreover, the strategy for the efficient and stable expression of recombinant proteins utilizing HEK-293 T cells can be employed as a universal platform for future vaccine development. [ABSTRACT FROM AUTHOR]

Marine fungal exopolysaccharides play a crucial role in immunoregulation. In this investigation, a novel polysaccharide was extracted from the culture medium of the marine fungus Aspergillus medius SCAU-236. Compositional analysis revealed a structure composed of glucose units with (1,4)-α-D-Glc p , (1,3,4)-β-D-Glc p , and (1,4,6)-α-D-Glc p , along with side chains of 1-α-D-Glc p linked to carbon 6 of (1,4,6)-α-D-Glc p and carbon 3 of (1,3,4)-β-D-Glc p. Functional evaluations on RAW264.7 macrophage cells demonstrated Aspergillus medius polysaccharide (ASMP)'s effects on cell proliferation, nitric oxide levels, and the secretion of TNF-α, IL-6, and IL-1β cytokines. Additionally, metabolomics indicated ASMP's potential to modulate macrophage immune function by impacting key regulatory molecules, including COX-2, iNOS, Nrf2, SLC7A11, GPX4, and ACSL4. The Nrf2/SLC7A11/GPX4 axis and ACSL4 were suggested to be involved in ASMP-induced ferroptosis, leading to increased reactive oxygen species (ROS) levels and lipid peroxidation. These findings propose a unique mechanism by which ASMP exerts immunomodulatory effects through ferroptosis induction, contributing to the understanding of marine-derived compounds in immunomodulation research. [ABSTRACT FROM AUTHOR]

Starch, a natural storage polysaccharide of plant kingdom, has many industrial applications. However, native starch has some inherent shortages, which can be overcome by structural modification. Dialdehyde starch, one kind of oxidized starch produced by periodate oxidation, has good physical properties and bioactivities with wide applications in different fields. Dialdehyde starch is typically achieved by oxidizing native starch slurry through periodate oxidation under controlled reaction conditions. Several factors including the source of starch, the type of oxidant, the molar ratio of oxidant to starch, reaction temperature, reaction time and solution pH value can influence the synthesis of dialdehyde starch. Dialdehyde starch shows different spectroscopic/chromatographic characters and physicochemical properties from native starch. Moreover, dialdehyde starch exhibits good antioxidant activity, antimicrobial activity and cross-linking property. Based on these functional properties, dialdehyde starch has shown application potentials in food packaging, thermoplastic production, enzyme immobilization, heavy metal ion adsorption, drug delivery, wood adhesion and leather tanning. In this review, the preparation conditions, structural characteristics, physicochemical properties, functional properties and potential applications of dialdehyde starch are summarized for the first time. The future research and development prospects of dialdehyde starch are also discussed. • Dialdehyde starch is achieved by oxidizing native starch through periodate oxidation. • Dialdehyde starch has different physicochemical properties from native starch. • Dialdehyde starch exhibits good antioxidant and antimicrobial activity. • Dialdehyde starch can act as a cross-linking agent with wide applications. • The function of dialdehyde starch is related to its oxidation degree. [ABSTRACT FROM AUTHOR]

The level of polysaccharides in the mature Lycium barbarum fruit (LBF) cell wall depends on their metabolism, trafficking, and reassembly within the cell. In this study, we examined the composition, content, and ultrastructure of the cell wall polysaccharides of LBF during maturation, and further analyzed cell wall polysaccharide remodeling using isotope tagging with relative and absolute quantification (iTRAQ)-based proteomics. The results showed that the contents of cellulose and hemicellulose tended to increase in the pre-maturation stage and decrease in the later stage, while pectin level increased before fruit maturing. The differential expression of the 54 proteins involved in the metabolic pathways for glucose, fructose, galactose, galacturonic acid and arabinose was found to be responsible for these alterations. The work provides a biological framework for the reorganization of polysaccharides in the LBF cell wall, and supports the hypothesis that pectic polysaccharide glycosyl donors come from starch, cellulose, hemicellulose and isomorphic pectin. [Display omitted] • Pectin content increased during LBF maturation through depolymerization. • 54 DEPs in the carbohydrate and energy metabolic pathway are major cell wall polysaccharide remodeling proteins. • Glucose, fructose, galactose, galacturonic acid and arabinose metabolic pathways are major remodeling pathways. • Potential sources of glycosyl donors for pectin are starch, cellulose, hemicellulose and isomorphic pectin. [ABSTRACT FROM AUTHOR]

Natural polysaccharides are important biopolymers with unique physicochemical properties and valuable biological activities. Due to the lack of sufficient functional groups, the applications of natural polysaccharides are incomparable to synthetic biopolymers. In order to broaden the applications of polysaccharides, gallic acid (GA, one kind of phenolic acid with numerous functional properties) has been grafted onto polysaccharides through several chemical and enzymatic methods. The structural characteristics and physical properties (e.g. water solubility, thermal stability, crystalline character and viscosity) of polysaccharides are greatly changed by grafting with GA. Meanwhile, GA grafted polysaccharides (GA-g-polysaccharides) show improved biological activities (e. g. antioxidant, antimicrobial, antitumor, anti-inflammatory, anti-allergic, enzyme inhibitory, prebiotic, and calcium oxalate crystals formation inhibitory effects) and broadened applications in the fields of active packaging, edible coating, encapsulation, delivery and bioadsorption. Notably, the structural characteristics, physical properties, biological activities and applications of GA-g-polysaccharides are affected by the grafting ratio and grafting method. Herein, recent advances of GA-g-polysaccharides in terms of preparation methods, structural characteristics, biological activities and potential applications are summarized. This review will provide a guideline for the scientific community towards more rational design and targeted use of GA-g-polysaccharides in the future. • The preparation methods of gallic acid grafted polysaccharides are introduced. • The structures of the conjugates are related to their preparation methods. • Factors affect the grafting ratio of the conjugates are summarized. • The conjugates possess several biological activities. • The conjugates are useful in food, pharmaceutical, and environmental fields. [ABSTRACT FROM AUTHOR]

Plant derived flavonoids have been demonstrated to possess many valuable biological functions. In recent years, flavonoids have been successfully conjugated with polysaccharides through different graft copolymerization methods including chemical coupling, enzyme catalysis, free radical mediated grafting, and acid catalyzed condensation reactions. The successful grafting of flavonoids onto polysaccharides can be confirmed by several instrumental methods. The conjugation of flavonoids can significantly improve the antioxidant, antimicrobial, antitumor, hepatoprotective and enzyme inhibition properties of polysaccharides. Moreover, the applications of polysaccharides in food and pharmaceutical industries can be greatly broadened by grafting with flavonoids. Flavonoid-grafted polysaccharides can be developed as films for active packaging, hydrogels for controlled drug release, micelles for oral drug delivery, and emulsions for nutraceutical delivery. In general, the bioactivities and applications of conjugates are closely related to the type of flavonoid grafted, the grafting method used as well as the grafting efficiency. Recent advances in the synthesis, structural characterization, bioactivities and potential applications of flavonoid-grafted polysaccharides are summarized in this review. [ABSTRACT FROM AUTHOR]

In this study, chitosan (CS) was degraded by ascorbate radical (Asc •− ) and hydroxyl radical ( • OH), respectively. The structural, physicochemical, antioxidant and film forming properties of Asc •− and • OH degraded CS were compared for the first time. Results showed the structure and physicochemical property of Asc •− degraded CS were significantly different from those of CS. Asc •− had a deamination effect on CS with the formation of several unsaturated bonds. Accordingly, Asc •− degraded CS showed decreased crystallinity and thermal stability as well as a planar morphology. By contrast, OH degraded CS showed similar structure, crystallinity and thermal stability to CS. However, OH had an erosion effect on CS with the formation of many cavities inside. Antioxidant assay further demonstrated that the in vitro antioxidant activity of CS was improved by Asc •− and OH degradations. Moreover, film forming property of CS was also altered by Asc •− and OH degradations. Asc •− and OH degraded CS films showed higher thicknesses, UV–vis light barrier property and water vapor permeability than CS film. Besides, Asc •− degraded CS film had better mechanical properties than CS and OH degraded CS films. Therefore, Asc •− degradation could be a useful approach to improve the antioxidant and film forming properties of CS. [ABSTRACT FROM AUTHOR]

In this study, a novel method was developed to conjugate quercetin with Cynanchum auriculatum starch. Quercetin was first succinylized and then grafted onto C. auriculatum starch through a N , N ′‑carbonyldiimidazole mediated reaction. The obtained water soluble quercetin grafted starch (quercetin-g-starch) was characterized by several instrumental methods. UV–vis spectrum of quercetin-g-starch aqueous solution exhibited two absorption bands at around 300 and 430 nm. Fourier-transform infrared spectrum of quercetin-g-starch showed characteristic bands at 1731 and 1568 cm −1 , assigning to C O stretching of esterified carboxyl group and C C stretching of aromatic ring, respectively. Proton nuclear magnetic resonance spectrum of quercetin-g-starch showed partial proton signals of starch (3.30–5.47 ppm) and quercetin (6.19–7.68 ppm). All above results suggested quercetin was successfully grafted onto C. auriculatum starch. Besides, quercetin-g-starch particles were irregular in shape and were in an amorphous state. Notably, the thermal stability, resistant starch content as well as antioxidant activity of C. auriculatum starch was greatly enhanced by grafting with quercetin. This indicated the potential of quercetin-g-starch in the development of a novel resistant starch with antioxidant activity. [ABSTRACT FROM AUTHOR]

Accurate determination of the distribution of substitutions in the primary molecular structure of heteropolysaccharides and their derivatives is a prerequisite for their increasing application in the pharmaceutical and biomedical fields, which is unfortunately hindered due to the lack of effective analytical techniques. Acetylated galactoglucomannan (GGM) is an abundant plant polysaccharide as the main hemicellulose in softwoods, and therefore constitutes an important renewable resource from lignocellulosic biomass for the development of bioactive and functional materials. Here we present a methodology for profiling the intramolecular structure of spruce GGM and its chemical derivatives (cationic, anionic, and benzoylated) by combining chemo-enzymatic hydrolysis, liquid chromatography, and mass spectrometry. Fast identification and qualitative mass profiling of GGM and its derivatives was conducted using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF-MS) and electrospray ionization mass spectrometry (ESI-MS). Tandem mass fragmentation analysis and its hyphenation with hydrophilic interaction liquid chromatography (HILIC-ESI-MS/MS) provide further insights on the substitution placement of the GGM oligosaccharides and its derivatives. This method will be useful in understanding the structure-function relationships of native GGM and their derivatives, and therefore facilitate their potential application. [ABSTRACT FROM AUTHOR]

The root of Cynanchum auriculatum Royle ex Wight is a traditional Chinese herbal medicine and healthy food. Although C. auriculatum has already been processed into starch for human consumption in China, the structural characterizations of C. auriculatum starch is still unknown. Therefore, the morphology, structural and physicochemical properties of C. auriculatum starch were investigated in this study. C. auriculatum starch exhibited both spherical and polygonal shapes with granule size ranging from 2 to 12 μm. Some void cavities and serpentine channels were observed in the inner of starch granules. X-ray powder diffraction pattern revealed that C. auriculatum starch was a C B -type with relative crystallinity of 25.19%. Small-angle X-ray scattering spectrum indicated C. auriculatum starch had a lamellar repeat distance of 9.21 nm. The proportions of single helix, double helix and amorphous components in C. auriculatum starch were 3.42%, 27.11% and 69.47%, respectively. The amylose content of C. auriculatum starch was 28.0% with the gelatinization temperature ranging from 59.3 to 70.1 °C. The maximum weight loss rate of C. auriculatum starch appeared at 309 °C. In addition, C. auriculatum starch showed higher swelling power than other starches tested. Our results suggest C. auriculatum starch will have wide applications in food industry. [ABSTRACT FROM AUTHOR]

In this study, protocatechuic acid (PA) was grafted onto chitosan (CS) by a carbodiimide mediated cross-linking reaction. The structural characterization, physical property and antioxidant activity of PA grafted CS (PA-g-CS) was investigated. As results, three copolymers with different grafting ratios (61.64, 190.11 and 279.69 mg PAE/g) were obtained by varying the molar ratios of reaction substrates. PA-g-CS showed the same UV absorption peaks as PA at 258 and 292 nm. As compared to CS, PA-g-CS exhibited a decreased band at 1596 cm −1 and a new band at 1716 cm −1 , suggesting the formation of amide and ester linkages between PA and CS. New proton signals at δ 6.77–7⋅33 ppm were observed on 1 H NMR spectrum of PA-g-CS, assigning to the methine protons of PA. Signals at δ 150.8–116.6 ppm on 13 C NMR spectrum of PA-g-CS was assigned to the aromatic ring carbon of PA moieties. All the structural information confirmed the successful grafting of PA onto CS. SEM observation showed CS had a smooth surface, while PA- g -CS had a rough surface. TGA revealed the thermal stability of PA-g-CS was lower than CS. Antioxidant activity assays further verified the reducing power and DDPH radical scavenging activity of PA-g-CS was much higher than CS. [ABSTRACT FROM AUTHOR]

In this study, structural characterization, physical property and antioxidant activity of catechin grafted Tremella fuciformis polysaccharide (catechin-g-TPS) were investigated. Crude polysaccharides were isolated from the fruit bodies of T. fuciformis and further purified on DEAE-52 and Sepharose CL-4B chromatography to afford a main purified fraction (named TPS). The molecular weight of TPS was determined as 5.82 × 10 5 Da by HPLC. Then, the free radical mediated grafting of catechin onto TPS was achieved by using a redox system. As compared with the unmodified TPS, catechin-g-TPS showed new bands within the range of 1300–1600 cm −1 in FT-IR spectrum, and exhibited new signals at around δ 6.00 and 6.80 ppm in 1 H NMR spectrum. Thermogravimetric analysis indicated the thermal stability of catechin-g-TPS was higher than TPS. X-ray diffraction spectrum of catechin-g-TPS exhibited two sharp narrow diffraction peaks at 14.2 and 32.1°, corresponding to the crystalline peaks of catechin. Scanning electron microscopy observation revealed the surface of TPS was smooth, whereas the surface of catechin-g-TPS was much rough. These results all confirmed the successful grafting of catechin onto TPS. Moreover, catechin-g-TPS had higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power as compared to TPS. [ABSTRACT FROM AUTHOR]

In this study, the antioxidant activity and hepatoprotective effect of inulin and catechin grafted inulin (catechin-g-inulin) against carbon tetrachloride (CCl 4 )-induced acute liver injury were investigated. Results showed that both inulin and catechin-g-inulin had moderate scavenging activity on superoxide radical, hydroxyl radical and H 2 O 2 , as well as lipid peroxidation inhibition effect. The antioxidant activity decreased in the order of Vc > catechin > catechin-g-inulin > inulin. Administration of inulin and catechin-g-inulin could significantly reduce the elevated levels of serum aspartate transaminase, alanine transaminase and alkaline phosphatase as compared to CCl 4 treatment group. Moreover, inulin and catechin-g-inulin significantly increased the levels of hepatic superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione and total antioxidant capacity, whereas markedly decreased the malondialdehyde level when compared with CCl 4 treatment group. Notably, catechin-g-inulin showed higher hepatoprotective effect than inulin. In addition, the hepatoprotective effect of catechin-g-inulin was comparable to positive standard of silymarin. Our results suggested that catechin-g-inulin had potent antioxidant activity and potential protective effect against CCl 4 -induced acute liver injury. [ABSTRACT FROM AUTHOR]

Optimization of extraction conditions, preliminary characterization and in vitro antioxidant activity of polysaccharides from black soybean (BSPS) were investigated. The results of Box-Behnken design showed that the optimal extraction conditions for BSPS were as follows: ratio of water to material of 20 ml/g, extraction time of 6.4 h and extraction temperature of 92 °C, with a corresponding yield of 2.56%. The crude BSPS were further fractionated on DEAE-52 and Sepharose CL-4B chromatography to afford three purified fractions (BSPS-1, BSPS-2 and BSPS-3). Chemical analysis showed that the three purified fractions were mainly composed of carbohydrate and uronic acid. In addition, BSPS-1 was composed of arabinose, rhamnose, galactose, glucose and mannose in the molar ratio of 1.79:1.00:2.59:26.54:1.01. BSPS-2 was composed of arabinose, rhamnose, xylose, galactose and mannose in the molar ratio of 8.10:4.80:9.15:13.38:1.00. BSPS-3 was composed of arabinose, rhamnose, galactose and mannose in the molar ratio of 16.80:3.60:33.66:1.00. The results of Fourier transform-infrared spectroscopy further confirmed the characteristic polysaccharide structures of the three purified fractions. Moreover, antioxidant assays showed crude BSPS and its purified fractions had potential superoxide anion and DPPH radical scavenging activities, and their antioxidant activity decreased in the order of crude BSPS > BSPS-3 > BSPS-2 > BSPS-1. [ABSTRACT FROM AUTHOR]

A neutral polysaccharide fraction (CGPP) was extracted from Gynostemma pentaphyllum by water extraction and ethanol precipitation. Gas chromatography (GC) analysis showed that the CGPP was mainly composed of mannose, glucose, arabinose, rhamnose, galactose and glucuronic acid in molar ratios of 2.0:2.2:1.3:2.2:1.2:2.5. The present study aimed at evaluating the antitumor potentials of CGPP on the growth of H22 tumor transplanted in mice and the underlying mechanism. The results showed that CGPP (50 and 200 mg/kg) could effectively inhibit the solid tumor growth of H22 hepatocarcinoma transplanted in ICR mice. Besides, the body weight, spleen/thymus indexes and splenocytes proliferation of H22 tumor bearing mice were also improved in CGPP-treated groups. Furthermore, the level of the cytokines, such as IL-2, TNF-α and IFN-γ, as well as the activity of natural killer (NK) cells and cytotoxic T lymphocytes (CTL) in tumor-bearing mice were markedly promoted by CGPP oral administration. In addition, CGPP treatment greatly prolonged the survival period in H22 ascites tumor-bearing mice. Taken together, these findings indicate that CGPP has antitumor activity in vivo at least partly via improving immune responses of host organism, and seems to be a safe and effective supplementary agent for the treatment of hepatocellular carcinoma (HCC). [ABSTRACT FROM AUTHOR]

Highlights: [•] Caffeic and ferulic acids were grafted onto chitosan by a free radical mediated method. [•] Copolymers had good free radical scavenging and peroxidation inhibition effects. [•] Copolymers significantly increased antioxidant enzymes activities and decreased malondialdehyde levels in d-galactose induced aging mice. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a novel biological macromolecule with strong in vitro anti-diabetic activity was developed by grafting catechin onto inulin via a free radical mediated method. The characterization, α-glucosidase and α-amylase inhibitory activities of catechin grafted inulin (catechin-g-inulin) were investigated. Results showed that the grafting ratio of catechin-g-inulin was 124.8mg CAE/g. UV–vis spectrum of catechin-g-inulin exhibited a new band at 280nm, attributing to B ring of catechin moiety. FT-IR spectrum of catechin-g-inulin showed new absorption bands between 1540 and 1418cm−1, attributing to C C stretching vibration of catechin moiety. 1H NMR spectrum of catechin-g-inulin preserved all the characteristic proton signals of inulin and partial signals of catechin. These all confirmed the successful grafting copolymerization. Conjugation probably occurred between OH of inulin (C–6) and H–6/H–8 of catechin (A ring). Catechin-g-inulin also exhibited increased thermal stability and crystallinity as compared to inulin. Moreover, in vitro anti-diabetic assays showed the α-glucosidase inhibitory activity decreased in the order of catechin-g-inulin>catechin>acarbose>inulin, and α-amylase inhibitory activity decreased in the order of catechin-g-inulin>acarbose>catechin>inulin. These indicated the potential of catechin-g-inulin in the development of a novel effective anti-diabetic agent. [Copyright &y& Elsevier]

Abstract: In this study, chitosan grafted copolymer with gallic acid (GA) was synthesized by a novel and efficient free radical mediated method. The optimal grafting conditions, structural characterization, α-glucosidase and α-amylase inhibitory activities of chitosan grafted copolymers were investigated. Results showed that the maximum grafting ratio (128.3mg GA equivalents/g) was obtained at 12h with 5g/L chitosan, 16g/L GA, 2g/L ascorbic acid and 0.2M hydrogen peroxide. UV–vis, Fourier-transform infrared and nuclear magnetic resonance spectroscopy all confirmed the successful grafting of GA onto chitosan. The conjugation of GA onto chitosan probably occurred between amine (C-2), hydroxyl groups (C-3 and C-6) of chitosan and carboxyl groups of GA, forming amide and ester linkages, respectively. Differential scanning calorimetry and X-ray diffraction spectra indicated that GA grafted chitosan (GA-g-chitosan) had decreased thermal stability and crystallinity as compared to chitosan. Notably, GA-g-chitosan showed increased α-glucosidase and α-amylase inhibitory activity with the increase of grafting ratio. These results indicated the potential of GA-g-chitosan in the development of an effective anti-diabetic agent. [Copyright &y& Elsevier]

Abstract: In this study, three phenolic acids including gallic acid (GA), caffeic acid (CA) and ferulic acid (FA) were grafted onto N,O-carboxymethyl chitosan (NOCC) by a free radical mediated grafting method. The grafted copolymers obtained were all water-soluble samples. UV–vis absorption peaks of the grafted copolymers shifted toward longer wavelengths. FT-IR spectroscopy of the grafted copolymers exhibited additional phenolic characteristics of the aromatic ring C C stretching within 1450–1650cm−1. NMR spectroscopy of the grafted copolymers showed new peaks at 6.2–7.6ppm assigned to the phenyl protons of phenolic acids. These results all confirmed the successful grafting of three phenolic acids to NOCC. The conjugation probably occurred at amine of NOCC and carboxyl groups of phenolic acids. The grafted copolymers exhibited decreased crystallinity as compared to NOCC and chitosan. Moreover, antioxidant activity in vitro assays showed that the antioxidant property decreased in the order of GA-g-NOCC>CA-g-NOCC>FA-g-NOCC>NOCC>chitosan. Our results suggested the potential of phenolic acids grafted NOCC for the development of effective antioxidant agents. [Copyright &y& Elsevier]

A chitosan-based nanoparticle was prepared using chitosan (CS) and O -carboxymethyl chitosan (O -CMCS). Our study revealed that chitosan/ O -carboxymethyl chitosan/tebuconazole nanoparticles (CS/ O -CMCS/TBA NPs) exhibited superior antifungal activity, foliar adhesion, and microbial target adhesion performance compared to commercial suspension concentrate (SC). The antifungal activity of CS/ O -CMCS/TBA NPs against C. gloeosporioides , with a 3.13-fold increase in efficacy over TBA (SC). We also found that low concentrations of CS/ O -CMCS NPs promoted the growth of C. gloeosporioides and enhanced the fungal catabolism of chitosan. Overall, the CS/ O -CMCS/TBA NPs were found to possess the remarkable capability to selectively aggregate around pathogenic microorganisms and CS/ O -CMCS NPs can enhance the fungal catabolism of chitosan. CS/ O -CMCS/TBA NPs, as a "sugar-coated bomb", was a promising asset for effective plant disease management and pesticide utilization through the affinity of chitosan-based nanoparticles and C. gloeosporioides , enabling targeted delivery and targeted release of their encapsulated active ingredient, which was important for the development and application of biocompatible chitosan-based nanopesticides. [Display omitted] [ABSTRACT FROM AUTHOR]

Three different extraction technologies including hot water extraction (HWE), enzyme assisted extraction (EAE) and ultrasonic cell grinder extraction (UCGE) were employed to extract crude ginger polysaccharides (GPs) under their respective best parameters, then crude GPs were purified by DEAE cellulose-52 and Sephadex G-200 size-exclusion chromatography in that order. Five GPs fractions (HGP, EGP1, EGP2, UGP1, and UGP2, respectively) were obtained. The differences of five GPs in chemical composition, characterization and antitumor activities were further compared. The molecular weights were different in five GPs, varying from 11.81 to 1831.75 kDa. Mannose and glucose as the main monosaccharide and the glycosidic linkage of →4)-α-D-Glc(1→ and -α-Manp-(1→ existed in both five GPs. While EGP2 and UGP1 possessed specific structure of →6)-β-D-Galp-(1→ and UGP1 contained more sulfate group. Moreover, UGP1 exhibited strong inhibitory effect on three tumor cells especially the colon cancer. The inhibition rates of UGP1 on H1975, HCT116 and MCF-7 were 23.339 ± 2.285%, 56.843 ± 2.405% and 21.061 ± 1.920% respectively. The study indicated GPs extracted by UCGE could reserve more active structure and inhibit colon cancer more significantly. [ABSTRACT FROM AUTHOR]

In recent years, porous starch has attracted increasing attention due to its valuable functions and potential applications. Here, we present a comprehensive review of the recent advances of porous starch in different aspects, including the preparation and structural characterization methods, physicochemical properties, and potential applications. In general, different techniques including physical, chemical and enzymatic as well as their synergic methods have been extensively used to prepare porous starch. The prepared porous starch can be characterized by several instrumental methods including pore structure analyzer, scanning electron microscopy, X-ray diffractometer, Fourier-transform infrared spectroscopy, and nuclear magnetic resonance. As compared to native starch, porous starch shows enhanced adsorption efficiency, solubility and swelling power. Moreover, porous starch can be used to adsorb, encapsulate and release different substances. This review will provide a guideline for the rational preparation and applications of porous starch in the future. • Recent advances of porous starch are summarized. • Porous starch can be produced by physical, chemical, enzymatic and synergic methods. • Porous starch shows enhanced adsorption efficiency, solubility and swelling power. • Porous starch can be used to adsorb, encapsulate and release different substances. [ABSTRACT FROM AUTHOR]

In this study, the structural characterization and anti-inflammation effect of dilute alkali-soluble polysaccharides from purple sweet potato were investigated. Three fractions (F-1, F-2 and F-3) were obtained by purifying crude polysaccharides on DEAE-52 cellulose column. The main fraction (F-1) was further purified on Sephadex G-200 column to afford purified alkali-soluble sweet potato polysaccharide (ASPP). The chemical structure of ASPP was analyzed by gas chromatography, Fourier transform infrared spectroscopy, methylation analysis and nuclear magnetic resonance spectroscopy. Monosaccharide compositional analysis showed ASPP was composed of rhamnose, arabinose, xylose, mannose and glucose in the molar ratio of 2.8:1.9:1.0:7.6:53.3. Moreover, the backbone of ASPP was composed of 1,4-linked Glc p with side chains attached to the O-6 position. The anti-inflammation effect of ASPP was further investigated by in vitro and in vivo experiments. Results showed ASPP could inhibit the levels of nitric oxide, interleukin (IL)-6, IL-1β and TNF-α but increase the production of IL-10 in lipopolysaccharide (LPS)-treated RAW 264.7 macrophage cells. In addition ASPP could reduce the secretion of IL-6, IL-1β and TNF-α in LPS-treated mice. Our results suggest ASPP can be developed as a novel anti-inflammation agent. • Alkali-soluble polysaccharide (ASPP) was isolated from purple sweet potato. • ASPP was linear α-(1→4)-glucan with side chains attached to O-6 position. • ASPP had anti-inflammation effects both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Abstract Immune-enhancing effects of three kinds of purple sweet potato polysaccharides (PSPPs) including water-soluble polysaccharide (WSP), dilute alkali-soluble polysaccharide (DASP) and concentrated alkali-soluble polysaccharide (CASP) were evaluated. Scanning electron microscope analysis showed that all PSPPs could stimulate the formation of microvilli-like structures in cellular surfaces, which was possibly related to activation of macrophages. Neutral red uptake assay showed that PSPPs could increase the phagocytic activity of cells. High dose (400 μg/mL) of PSPPs could notably augment the level of nitric oxide (NO). ELISA analysis revealed that 200 and 400 μg/mL of PSPPs distinctly elevated the production of IL-1β. Cells received 200 and 400 μg/mL of WSP as well as 400 μg/mL of DASP exhibited higher level of IL-6. Results of animal experiments showed that WSP treatment (400 mg/kg) could promote the secretions of IgA, IgG, IgM and sIgA in both normal and immunosuppressed mice. Moreover, CASP treatment (400 mg/kg) elevated the production of IgM in the serum of normal and immunosuppressive mice, while DASP (400 mg/kg) only improved the secretion of IgM in normal mice. In summary, all three polysaccharides can stimulate immune responses of macrophages and positively regulate adaptive immunity by enhancing the production of immunoglobulins in mice. Highlights • Three kinds of polysaccharides were successively extracted from purple sweet potato. • All the polysaccharides could enhance immunomodulatory activity of macrophages. • Polysaccharides possessed ability to stimulate production of serum immunoglobulins. • Polysaccharides had potential to regulate innate and adaptive immunity. [ABSTRACT FROM AUTHOR]

Abstract Desalination of marine species has become an important development direction for aquaculture in China and other countries. However, that how to regulate the salt balance to adapt to new freshwater habitats is a serious challenge for marine species in desalination of aquaculture. In the study, Chinese mitten crabs (Eriocheir japonica sinensis) was selected to analyse the adaptively differential expression in salinity changes for their novel characteristics of life history. The results showed that gill was the most relevant tissue in osmoregulation that was validated by biomarkers (Na+/K+-ATP, V-type H+-ATPase) with qPCR. Na+/K+-ATPase is a primary transporter and maintains the body fluid osmolality by actively pumping Na+ to the hemolymph, and V-type H+-ATPase is responsible for acid-base balance and nitrogen excretion. So both transcriptome data and qPCR results showed the significantly differential expression of Na+/K+-ATPase and V-type H+-ATPase in gills. Moreover, NAK-α had the most significantly differential expression level in salinity change, and other genes such as GST , HSP90 , S27 , UBE , VATB also revealed significantly up-regulation. They are considered the key enzymes during the transition from a marine environment to land. Present results have provided a foundation to further understand the molecular adaptive mechanism in desalination of marine species. [ABSTRACT FROM AUTHOR]

In vivo hepatoprotective effect of a novel arabinogalactan (AG) from black soybean on carbon tetrachloride (CCl 4 )-induced acute liver injury was evaluated for the first time. Our results showed that administration of AG could significantly attenuate the increase in the levels of alkaline phosphatase, alanine transaminase and aspartate transaminase in the serum caused by CCl 4 treatment. AG treatment not only significantly elevated the levels of antioxidant enzymes including superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase; but also increased the levels of non-enzyme antioxidants (glutathione and total antioxidant capacity in liver tissues) when compared with CCl 4 -induced acute liver injury model. In addition, AG significantly reduced lipid peroxidation levels in liver tissues. The hepatoprotective effect of high-dose of AG was comparable to that of silymarin, which served as a positive standard. This study indicated that AG had a protective effect on CCl 4 -induced acute liver injury. [ABSTRACT FROM AUTHOR]

This study investigated the effects of dietary chitosan on growth, antioxidant, immunity, intestinal morphology and resistance against Aeromonas hydrophila of hybrid sturgeon (Acipenser baerii♀ × Acipenser schrenckii ♂). Sturgeons (18.18 ± 0.08 g) were randomly divided into four groups, fed with chitosan-supplemented diets for 8 weeks and then infected with A. hydrophila. The results showed significant differences of body weight gain, specific growth rate and feed conversion ratio in sturgeon fed chitosan and control diets. The oral administration of chitosan significantly increased the acid phosphatase, alkaline phosphatase, lysozyme, myeloperoxidase, superoxide dismutase, glutathione peroxidase and catalase activities, as well as the complement 3 and 4 contents and disease resistance against A. hydrophila. Moreover, enhancement of muscular thickness and goblet cells in mid intestine and increase of muscular thickness and villus height in spiral valve were observed in the chitosan supplemented groups. In addition, dietary chitosan-supplemented diets mitigated the changes of antioxidant and immune activity induced by A. hydrophila challenge, as well as prevented fish from bacterial invasion. The optimal dose was 3.00 g chitosan/kg diet for hybrid sturgeon. • Chitosan increased body weight, antioxidant and immune activity of hybrid sturgeon. • Chitosan improved the intestine enzyme activity and morphology in hybrid sturgeon. • Chitosan mitigated changes of antioxidant and immune activity induced by infection. • Chitosan inhibited the bacteria invasion and protected fish from bacterial infection. • The optimal chitosan level for hybrid sturgeon was recommended as 3.00 g/kg diet. [ABSTRACT FROM AUTHOR]

In this study, four dialdehyde starch-catechin (DAS-catechin) conjugates were prepared by conjugating (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG) and (-)-epigallocatechin gallate (EGCG) with dialdehyde starch. Then, DAS-catechin conjugates were used as antioxidant and cross-linking agents to produce chitosan (CS) based antioxidant packaging films. The functionality of CS/DAS-catechin conjugate films was determined. Results showed four DAS-catechin conjugates formed Schiff-base linkages and hydrogen bond interactions with CS, resulting in improved film uniformity. Compared with plain CS film, CS/DAS-catechin conjugate films owned higher UV–vis light, water vapor and oxygen barrier ability, lower swelling degree, and stronger tensile strength, thermal stability and antioxidant activity. The cross-linking between CS and DAS-catechin conjugates delayed the biodegradable process of CS film. CS/DAS-catechin conjugate films showed good performance on inhibiting sunflower seed oil oxidation. Notably, CS/DAS-ECG conjugate film had the highest oxygen barrier, mechanical and antioxidant performances among four CS/DAS-catechin conjugate films. Therefore, CS/DAS-ECG conjugate film is an antioxidant packaging candidate for edible oil. • Chitosan film was cross-linked by dialdehyde starch-catechin conjugates. • Conjugates formed Schiff-base linkages and hydrogen bonds with chitosan. • Conjugates elevated the barrier, mechanical and antioxidant properties of film. • Film with dialdehyde starch-epicatechin gallate conjugate had the best performance. [ABSTRACT FROM AUTHOR]

Infection is a huge obstacle to wound healing. Thus, to enhance the healing of infected wounds, wound dressings that permit the dual delivery of antimicrobials and antioxidants are highly desirable. In this study, a series of gelatin-based nanofiber membranes with different curcumin contents were fabricated via solution electrospinning. The obtained membranes were characterized in terms of their morphologies, in addition to their physical, mechanical, and in vitro properties. The results showed that the membranes maintained an integrated morphology, excellent water absorption capability, satisfactory mechanical properties, and a high dissolution rate of curcumin. The addition of curcumin and borneol conferred the membranes the ability to inhibit Staphylococcus aureus and eliminate free radicals. Furthermore, cytocompatibility testing using the L929 cell line confirmed the excellent biocompatibility of the membranes. These gelatin-based nanofiber membranes loaded with curcumin and borneol can therefore be considered as promising materials for dressing wounds. Moreover, the use of biodegradable polymers and environmentally sustainable production techniques in this system render it suitable for the commercial manufacture of composite membranes. • Curcumin and borneol were successfully loaded on membranes. • Fabricated membranes show Antibacterial and Antioxidant properties. • Fabricated membranes show excellent mechanical and sound cytocompatibility. [ABSTRACT FROM AUTHOR]

Carboxymethyl chitosan (CMCS) is a useful polysaccharide with potential applications in food, cosmetic and biomedical industries. Nonetheless, CMCS is unfavorable for maintaining intestinal flora balance. In this study, gallic acid (GA) was grafted with CMCS through ascorbic acid/hydrogen peroxide initiated graft copolymerization reaction, producing GA grafted CMCS (GA-g-CMCS). The digestive and fermentative behavior of CMCS and GA-g-CMCS were investigated by using in vitro simulated gastrointestinal digestion and colonic fermentation models. Results showed that the average molecular weight (M w) of CMCS gradually decreased during saliva-gastro-intestinal digestion, changing from original sheet-like morphology to porous and rod-like fragments. However, the M w and morphology of GA-g-CMCS were almost unchanged under saliva-gastro-intestinal digestion. Meanwhile, the grafted GA moiety was not released from GA-g-CMCS during saliva-gastro-intestinal digestion. As compared with CMCS fermentation, GA-g-CMCS fermentation significantly suppressed the relative abundance of Escherichia-Shigella , Paeniclostridium, Parabacteroides , Lachnoclostridium , Clostridium_sensu_stricto_1 , UBA1819 and Butyricimonas , while facilitated the relative abundance of Enterobacter , Enterococcus , Fusobacterium and Lachnospira. In addition, GA-g-CMCS fermentation significantly enhanced the production of short-chain fatty acids. These findings suggested that the digestive stability and prebiotic effect of CMCS were improved by grafting with GA. • Gallic acid (GA) was grafted onto carboxymethyl chitosan (CMCS) by covalent bond. • CMCS was gradually degraded during saliva-gastro-intestinal digestion. • GA-g-CMCS was very stable under saliva-gastro-intestinal digestion. • The prebiotic effect of GA-g-CMCS was improved by grafting GA. • GA-g-CMCS fermentation promoted the production of short-chain fatty acids. [ABSTRACT FROM AUTHOR]

Xyloglucan (XG), as a natural biopolymer, possesses a sound biocompatibility and an impressive biodegradability, which are usually featured with abundant hydroxyl groups available for the bioconjugation with a bioactive moiety, suggesting a promising or unique value possibly applied in the field of biomedicine. In this study, XG was extracted from Tamarind seeds and subjected to four regioselective oxidation methods to introduce carboxyl groups onto the XG molecules for a bioconjugation with collagen. Galactose oxidase and reducing end aldehyde group oxidation mainly resulted in a low carboxylate content at ∼0.34 mmol/g, whereas the primary and secondary hydroxyl group oxidations would lead to a high carboxyl content at ∼0.84 mmol/g. The number-average molar mass (Mn) and weight-average molar mass (Mw) of XG were 8.8 × 105 g/mol and 1.1 × 106 g/mol, respectively. The oxidized XGs were then subjected to a further biofunctionalization with the collagen through EDC/NHS coupling, which exhibited a degree of conjugation rate, ranged from 50 % to 72 %. The collagen-conjugated at the C6 position of XGs exhibited the highest cell viability recorded at 168 % in promoting cell growth and proliferation after 72 h of culture, surpassing that of pure collagen recorded at 138 %, which may indeed suggest a promising value in a biomedical application. [ABSTRACT FROM AUTHOR]

Active/intelligent packaging films were developed by incorporating purple sweetpotato anthocyanins (PSA) and purple cabbage anthocyanins (PCA) in locust bean gum/polyvinyl alcohol (LP), chitosan/polyvinyl alcohol (CP) and κ -carrageenan/polyvinyl alcohol (KP) film matrices. The joint effect of anthocyanins' source and polysaccharides' nature on the structure and functionality of the films was determined. Results showed PSA and PCA interacted with film matrices through hydrogen bonds and/or electrostatic interactions, resulting in improved film uniformity. PSA and PCA did not remarkably alter the water vapor permeability and tensile strength of the films; however, significantly improved the light barrier ability, antioxidant activity, pH-sensitivity and ammonia-sensitivity of films. For the films containing the same anthocyanins (PSA or PCA), LP-based films had relatively higher light barrier ability and storage stability, while CP-based had relatively weaker color changeable ability. When PSA and PCA were immobilized in the same film matrix, the films containing PCA had higher light barrier ability and antioxidant activity than the films containing PSA. Among the films, LP-PCA film exhibited a good potential to monitor the freshness of shrimp. Results suggested the structure and functionality of the films were influenced by the source of anthocyanins and the nature of polysaccharides. • Films were made based on different anthocyanins and polysaccharide/PVA matrices. • Anthocyanins-film matrix interactions depended on polysaccharides' nature. • Anthocyanins' source and polysaccharides' nature had joint effect on the films. • Polysaccharides' nature affected water vapor permeability and tensile strength. [ABSTRACT FROM AUTHOR]

Loropetalum chinense var. rubrum is an ornamental shrub rich in polyphenolic compounds. In this study, polyphenolic compounds were extracted from L. chinense var. rubrum petals (LCP) and further purified on macroporous resin column to afford two fractions. The crude extract of LCP (LCP-CE) and its two purified fractions (LCP-25PF and LCP-50PF) were individually incorporated into locust bean gum/polyvinyl alcohol matrix to develop smart packaging films. The structures, physical and functional properties of the films were compared. Results showed LCP-25PF was mainly composed of anthocyanins, while LCP-50PF was mainly composed of chlorogenic acid and vanillin. LCP-CE, LCP-25PF and LCP-50PF interacted with locust bean gum/polyvinyl alcohol matrix through hydrogen bonds, thereby improving the light and oxygen barrier ability, tensile strength, thermal stability, antioxidant activity and antimicrobial activity of the film. The film containing LCP-25PF showed the lowest water vapor permeability (10.36 × 10−11 g m−1 s−1 Pa−1) and oxygen permeability (0.42 cm3 mm m−2 day−1 atm−1) but the highest tensile strength (29.76 MPa), antioxidant activity and antimicrobial activity. In addition, the films containing LCP-CE and LCP-25PF had pH-/ammonia-sensitivity and effectively indicated shrimp freshness at 4 °C. Results suggested the film containing LCP-25PF could be used as smart packaging film. • Petal polyphenols were purified into two fractions by macroporous resin. • Smart packaging films were made by using petal extract and its purified fractions. • Anthocyanins-rich purified fraction improved the miscibility of film matrix. • Anthocyanins elevated the barrier, antioxidant and antimicrobial properties of film. • Films containing anthocyanins effectively indicated the freshness of shrimps. [ABSTRACT FROM AUTHOR]

Nanocellulose-based biomaterials have gained significant attention in various fields, especially in medical and pharmaceutical areas, due to their unique properties, including non-toxicity, high specific surface area, biodegradability, biocompatibility, and abundant feasible and sophisticated strategies for functional modification. The biosafety of nanocellulose itself is a prerequisite to ensure the safe and effective application of biomaterials as they interact with living cells, tissues, and organs at the nanoscale. Potential residual endogenous impurities and exogenous contaminants could lead to the failure of the intended functionalities or even serious health complications if they are not adequately removed and assessed before use. This review summarizes the sources of impurities in nanocellulose that may pose potential hazards to their biosafety, including endogenous impurities that co-exist in the cellulosic raw materials themselves and exogenous contaminants caused by external exposure. Strategies to reduce or completely remove these impurities are outlined and classified as chemical, physical, biological, and combined methods. Additionally, key points that require careful consideration in the interpretation of the biosafety evaluation outcomes were discussed to ensure the safety and effectiveness of the nanocellulose-based biomaterials in medical applications. [ABSTRACT FROM AUTHOR]

The soybean glycinin (11S)-chitosan (CS) complex gels with various textural properties were successfully constructed. The process involved the initial formation of 11S-CS coacervates through electrostatic interactions, followed by a heating treatment to obtain the final complex gels. The impacts of pH, heating temperature, and centrifugation on 11S-CS complex gel properties were investigated. The results indicated that the pore arrangement of the gel formed at pH 7.3 was more tightly and uniformly packed than those formed at pH 6.8 and 7.8. Centrifugation facilitated denser and more ordered gel structures at the three pH values, while increasing the heating temperature exhibited the opposite trend at pH 6.8 and 7.8. These structural differences were also reflected in the rheological and textural properties of the gel. The 11S-CS complex gels exhibited an elasticity-based gel property. The textural properties of gels formed at pH 6.8 were stronger compared to those formed at pH 7.3 and 7.8. However, when the 11S-CS coacervates were heated without centrifugation, the resulting gels were weak. This study emphasizes the potential of using protein/polysaccharide associative interactions during gel formation to alter the microstructure of the gel, meeting various production requirements. • 11S-CS complex gel was formed by heating electrostatic coacervates. • Centrifugation treatment contributed to denser gel structure with better elasticity. • 11S-CS complex gel exhibited an elasticity-based gel property. • pH, T°, and centrifugation affect the texture of 11S-CS complex gel. [ABSTRACT FROM AUTHOR]

In this study, chitosan (CS) was conjugated with epicatechin gallate (ECG) to prepare CS-ECG conjugates with different substitution degrees (5.18 %, 6.36 % and 7.74 %). Then, antioxidant packaging films were fabricated by blending CS and CS-ECG conjugates. The impact of CS-ECG conjugates' substitution degree on the functionality of CS/CS-ECG films was determined. CS-ECG conjugates showed UV absorption at 275 nm, proton signal at 6.85 ppm and infrared absorption at 1533 cm−1, assigning to the conjugated ECG. As compared with CS, CS-ECG conjugates exhibited less crystalline state but higher antioxidant activity. The structural characterization of CS/CS-ECG films showed CS and CS-ECG conjugates formed hydrogen bonds. CS/CS-ECG films displayed 26.35 %–29.23 % water solubility, 85.61°–86.96° water contact angle, 3.11–3.41 × 10−11 g m−1 s−1 Pa−1 water vapor permeability, 0.29–0.34 cm3 mm m−2 day−1 atm−1 oxygen permeability, 31.54–36.20 MPa tensile strength, 50.12 %–56.40 % elongation at break, as well as potent antioxidant activity and oil oxidation inhibitory ability. Notably, the film containing CS-ECG conjugate with 7.74 % substitution degree had the strongest barrier ability, mechanical property, antioxidant activity and oil oxidation inhibitory ability. Results suggested the substitution degree of CS-ECG conjugates was positively correlated with the barrier, mechanical and antioxidant properties of CS/CS-ECG films. • Chitosan (CS) was reacted with epicatechin gallate (ECG) to prepare conjugates. • Antioxidant packaging films were fabricated based on CS and CS-ECG conjugates. • ECG changed the crystallinity, morphology and antioxidant activity of CS. • CS-ECG conjugates improved the barrier, mechanical and antioxidant activity of films. • The substitution degree of conjugates positively affected the functionality of films. [ABSTRACT FROM AUTHOR]

In this study, a hexagonal plate ultrasound (HPU) pretreatment technology was employed to modify soy protein isolate (SPI) and enhance the hypocholesterolemic activity of enzymatic digests from SPI. Results demonstrated that under the condition of ultrasound power density of 40 W/L, the hypocholesterolemic activity of enzymatic digests from HPU-pretreated SPI (HPU-SPI) increased by 88.40 % compared to control group after gastrointestinal digestion. The sulfhydryl content of HPU-SPI increased by a maximum of 45.32 % compared to control group. Fourier transform infrared and scanning electron microscopy revealed that HPU pretreatment partially unfolded the SPI conformation, reduced the intermolecular interactions, and exposed the internal hydrophobic regions. Pearson correlation analysis showed that sulfhydryl groups (r = 0.860), disulfide bonds (r = −0.875) and random coil (r = 0.917) were strongly correlated with the cholesterol-lowering activity of soy protein hydrolysate (SPH), following a simulated gastrointestinal digestion. Finally, the effects of HPU pretreatment on enzymolysis kinetics and thermodynamics of the SPI enzymatic process showed that HPU pretreatment significantly reduced the Mie's constant, activation energy, activation enthalpy, activation entropy and Gibbs free energy. Overall, the study outcome suggested that HPU pretreatment could positively influence the hypocholesterolemic peptide activity, and thus, may be beneficial to the pharmaceutical/food industry. [ABSTRACT FROM AUTHOR]

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. • We investigated that ultrasonication made the (SPI)/(SHP) complex more stable. • SHP improved the emulsification and stability of the composite emulsions. • SHP improved the sensory quality and storage stability of fermented products. [ABSTRACT FROM AUTHOR]

Cockscomb (Celosia cristata L.) is an edible and ornamental plant rich in natural pigments of betacyanins. In this study, smart packaging films were developed based on locust bean gum (LBG), polyvinyl alcohol (PVA) and betacyanins from cockscomb flower. Effect of cockscomb flower extract content (4 wt%, 8 wt% and 12 wt%) on the structural, physical and functional properties of LBG/PVA blend films was investigated. The addition of cockscomb flower extract elevated the immiscibility between LBG and PVA. Cockscomb flower extract interacted with LBG and PVA through hydrogen bonds, resulting in reduced film crystallinity. The film containing 8 wt% of cockscomb flower extract showed the lowest water vapor permeability (10.34 × 10−11 g m−1 s−1 Pa−1) and the highest tensile strength (23.63 MPa). The film containing 12 wt% cockscomb flower extract exhibited the lowest light transmittance and the highest elongation at break (41.12%) and antioxidant activity. Cockscomb flower extract made the films become reddish-purple and endowed the films with pH-sensitivity and ammonia-sensitivity. The films containing cockscomb flower extract showed obvious color changes from reddish-purple to brown/yellow when shrimp spoiled. Our results suggested LBG/PVA blend films with cockscomb flower extract were suitable smart packaging films for indicating shrimp freshness. • Smart packaging films were prepared based on betacyanins from cockscomb flower. • Cockscomb flower extract improved the homogeneity of films. • Cockscomb flower extract elevated light barrier and antioxidant abilities of films. • Cockscomb flower extract endowed films with pH-/ammonia-sensitivity. • The prepared films effectively indicated the freshness of shrimp. [ABSTRACT FROM AUTHOR]

Chitosan (CS) films containing 0, 1, 3 and 5% (w/w) of polyphenol-rich rambutan peel extract (RPE) were developed. The micro-structural characterization and physical and functional properties of the films were determined. Results showed RPE formed strong interactions with CS, making film inner micro-structure become uniform and film crystallinity decline. Amongst different films, CS film containing 5% of RPE showed the lowest light transmission, moisture content (28.35%), water solubility (46.07%), water vapor permeability (8.41 × 10−10 g m−1 s−1 Pa−1) and oxygen permeability (0.28 cm3 mm m−2 day−1 atm−1). Meanwhile, CS film containing 5% of RPE exhibited the highest tensile strength (38.87 MPa) and elongation at break (51.73%) and the strongest antioxidant and antimicrobial activities. Finally, pork was wrapped with the films and stored at 4 °C for 8 days. Results showed pork wrapped with CS film containing 5% of RPE presented the lowest total volatile basic nitrogen level (9.17 mg/100 g), thiobarbituric acid reactive substance value (0.51 mg malondialdehyde/kg) and total viable count (4.53 log colony forming unit/g) and the best sensory attributes on the eighth day. Our results suggested the potential of CS film containing 5% of RPE as an active packaging material in pork preservation. • Active chitosan films were prepared by incorporating rambutan peel extract (RPE). • RPE made the films become compact and show decreased crystallinity. • RPE elevated the barrier ability and mechanical property of the films. • RPE enhanced the antioxidant and antimicrobial activity of the films. • CS-RPE films extended the shelf life of cold-stored pork to 8 days. [ABSTRACT FROM AUTHOR]

In this study, active and smart packaging films were prepared by individually adding betacyanins-rich plant extracts (red pitaya flesh extract (RPFE), prickly pear fruit extract (PPFE), red beetroot extract (RBRE), globe amaranth flower extract (GAFE) and red amaranth leaf extract (RALE)) into starch/polyvinyl alcohol. The structural, physical and functional properties of the films containing betacyanins from different plant sources were compared for the first time. Results showed betacyanins from RPFE, PPFE and RBRE were betanin-type betacyanins. Betacyanins from GAFE and RALE were gomphrenin-type and amaranthin-type betacyanins, respectively. The films containing RPFE and PPFE presented more uniform cross-sections and had the highest water vapor barrier (9.37 and 9.26 × 10−11 g m−1 s−1 Pa−1) and mechanical strength (8.26 and 7.87 MPa). However, the film containing GAFE presented the lowest light transmittance but the highest 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (EC 50 = 0.47 mg/mL). All the films containing betacyanins are sensitive to pH 8–12 buffer solutions and volatile ammonia. Notably, the film containing RPFE exhibited distinct color changes (from purple-red to pink) when shrimp spoiled. Our results suggest the structural, physical and functional properties of betacyanins-rich films are closely related to the source and type of betacyanins. • Active/smart films were prepared based on different types of betacyanins. • Film with red pitaya flesh/prickly pear extract had the highest mechanical properties. • Film containing globe amaranth flower extract had the highest antioxidant activity. • Film with red pitaya flesh extract was suitable for shrimp freshness monitoring. [ABSTRACT FROM AUTHOR]

Luteolin is a flavone with potent antioxidant and antimicrobial activities. In this study, luteolin was encapsulated in oil-in-water nanoemulsions that were emulsified by glycerol monooleate and Tween 20. Results showed 68 mg luteolin-loaded nanoemulsions had the highest stability (zeta potential of −39.8 mV) and encapsulation efficiency (89.52%). Then, active packaging films were developed by incorporating free or nano-encapsulated luteolin into chitosan-based matrix. The microstructure, physical and functional properties of CS film containing free luteolin (CS-LL) or nano-encapsulated luteolin (CS-LLNEs) were compared. Different from CS film, CS-LL and CS-LLNEs films had compact inner microstructure and strengthened intermolecular interactions. Moreover, CS-LLNEs film was more homogenous and compact than CS-LL film. As a result, CS-LLNEs film presented higher water vapor and oxygen barrier abilities and mechanical properties in comparison with CS-LL film. In addition, CS-LLNEs film showed slower release rate of luteolin in 95% ethanol (fatty food stimulant) as compared with CS-LL film. The controlled release of luteolin from film matrix could guarantee CS-LLNEs film to exert antioxidant activity up to 10 days. Our results suggest CS-LLNEs film can be developed as an emerging active packaging material that has potential applications in food industry. • Luteolin was encapsulated in oil-in-water nanoemulsions. • Packaging films were developed based on chitosan and free or encapsulated luteolin. • The addition of free or encapsulated luteolin into chitosan produced compact films. • Film with encapsulated luteolin had better water vapor/oxygen barrier properties. • Film with encapsulated luteolin exhibited antioxidant activity up to 10 days. [ABSTRACT FROM AUTHOR]

In this study, cassava starch aldehyde was functionalized with catechin through acid catalyzed condensation reaction. The structural characterization, stability and antioxidant activity of starch aldehyde-catechin conjugates were investigated. Thin layer chromatography revealed the conjugates did not contain free catechin. UV–vis spectra of the conjugates exhibited an absorption band at 280 nm, attributing to the B-ring of catechin moiety. Fourier-transform infrared and proton nuclear magnetic resonance spectroscopy demonstrated the conjugation occurred between the H–6/H–8 of catechin A-ring and the aldehyde groups of starch aldehyde. X-ray diffraction pattern indicated that the conjugates had an amorphous structure. Scanning electron microscopy showed the conjugates were fragmentary slices with rough surfaces. Notably, the conjugates were more stable than catechin in phosphate buffered saline (pH 7.4). In addition, the conjugates could not be digested in simulated saliva, gastric and small intestinal juices. The reducing power and free radical scavenging activity of starch aldehyde were remarkably elevated by conjugating with catechin. Meanwhile, the conjugates were non-cytotoxic to RAW264.7 mouse macrophage cells and possessed higher resistant starch contents than starch. Our results suggest starch aldehyde-catechin conjugates can be used as antioxidants in food industry. • Starch aldehyde-catechin conjugates were synthesized by graft copolymerization. • Conjugation occurred between catechin A-ring and starch aldehyde groups. • The conjugates were more stable than catechin. • The conjugates showed higher antioxidant activity than starch aldehyde. • The conjugates had higher resistant starch content than starch and starch aldehyde. [ABSTRACT FROM AUTHOR]

The interactions between carboxymethyl cellulose sodium and proteins can regulate the interfacial and rheological properties of HIPEs, which plays a leading role in the stabilities of HIPEs. This article prepared various ratios of soluble soy protein isolate/carboxymethyl cellulose sodium (SPI/CMC) complexes in different proportions and examined the impact of various ratios of complexes on the structure and interface properties of complexes systems. Additionally, it explored the co-emulsification mechanism of HIPEs using SPI and CMC. At appropriate ratios of SPI/CMC, SPI and CMC mainly combine through non covalent binding and form complexes with smaller particle sizes and stronger electrostatic repulsion. The interfacial properties indicated that adding appropriate CMC increased the pliability and reduced the interfacial tension, while also enhancing the wettability of SPI/CMC complexes. At the ratio of 2:1, the SPI/CMC complexes-stabilized HIPPEs exhibited smaller oil droplets size, tighter droplet packing, and thicker interfacial film through the bridging of droplets and the generation of stronger gel-like network structures to prevent the coalescence/flocculation of droplets. These results suggested that the appropriate ratios of SPI/CMC can improve the physical stability of HIPEs by changing the structure and interface characteristics of the SPI/CMC complexes. This work provided theoretical support for stable HIPEs formed with protein-polysaccharide complexes. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing efficient and safe antibacterial agents to inhibit pathogens including Physalospora piricola and Staphylococcus aureus is of great importance. Herein, a novel compound composed of Rosa roxburghii procyanidin, chitosan and selenium nanoparticle (RC-SeNP) was bio-synthesized, with the average diameter and zeta potential being 84.56 nm and −25.60 mV, respectively. The inhibition diameter of the RC-SeNP against P. piricola and S. aureus reached 18.67 mm and 13.13 mm, and the maximum scavenging activity against DPPH and ABTS reached 96.02% and 98.92%, respectively. Moreover, the RC-SeNP completely inhibited the propagation P. piricola and S. aureus on actual apples, suggesting excellent in vivo antimicrobial capacity. The transcriptome analysis and electron microscope observation indicated that the antibacterial activity would be attributed to adhering to and crack the cell walls as well as damage the cytomembrane and nucleus. Moreover, the RC-SeNP effectively maintained the vitamin C, total acid, and water contents of red bayberry, demonstrating potential application for fruit preservation. At last, the RC-SeNP showed no cell toxicity and trace selenium residual dose (0.03 mg/kg on apple, 0.12 mg/kg on red bayberry). This study would enlighten future development on novel nano-bioantibacterial agents for sustainable agriculture. • Novel compound composed of botanic procyanidin, chitosan and SeNP • Excellent in vitro antibacterial and antioxidant properties • Completely in vivo inhibition of P. piricola and S. aureus on apples • Application on red bayberry preservation with favorable antioxidant potential • Antibacterial mechanism by transcriptome analysis and micromorphology observation [ABSTRACT FROM AUTHOR]

Indigo (IND) and indirubin (INB) have demonstrated a synergistic effect in treating ulcerative colitis at a ratio of 7.5:1. However, the colon mucus layer, a critical physiological barrier against external threats, is also a biological barrier, limiting the potential for effective drug delivery to the lamina propria for regulating inflammatory cells. Inspired by the potential of Hyaluronic acid (HA), to enhance cellular uptake by inflammatory cells, and Pluronic® F127 (F127), known for overcoming the mucus barrier, this study innovatively developed INB/IND nanosuspensions by co-modifying with F127 and HA. Moreover, inulin serves a dual purpose as a spray protective agent and a regulator of intestinal flora. Therefore, it was incorporated into INB/IND nanosuspensions for subsequent spray drying, resulting in the preparation of INB/IND nanocrystals (INB/IND-NC). The mucus penetration of INB/IND-NC was 24.30 times that of the control group. Besides, INB/IND-NC exhibited enhanced cellular uptake properties proximately twice that of Raw INB/IND. Importantly, INB/IND-NC exhibited improved therapeutic efficacy in DSS-induced mice by regulating the expression of cytokines, regulating immune responses via downregulating the expression of macrophages, neutrophils, and dendritic cells and maintaining intestinal flora homeostasis. Our study provides a new perspective for applying natural products for treating inflammatory diseases. [ABSTRACT FROM AUTHOR]

The pH-response color-changeable films were prepared by adding different contents (1 %, 2 % and 3 %) of hyacinth bean anthocyanins (HBA) into guar gum/polyvinyl alcohol blend matrix. The structural characterization and optical, barrier, mechanical, thermal, antioxidant and color-changeable properties of the films were determined. The films were applied to monitor the freshness of chilled shrimp and pork. Results showed that HBA were pH-dependent color-changeable pigments that endowed the films with purple color. 2 % and 3 % of HBA improved the uniformity and compactness of the films by forming hydrogen bonds with film matrix. The barrier ability of the films against UV–vis light, water vapor and oxygen was significantly elevated by 2 % and 3 % of HBA. The mechanical, thermal and antioxidant properties of the films were improved by HBA. The films containing HBA were much sensitive to pH variation and ammonia vapor, presenting obvious color changes (purple→green→yellow-green). The films containing HBA showed good color stability when stored at 4 °C for 30 days. Moreover, the film containing 2 % HBA showed color changes (purple→green) when the chilled shrimp and pork decayed. The results suggested that the film containing 2 % HBA was suitable to monitor the freshness of meat products in intelligent packaging field. [ABSTRACT FROM AUTHOR]

During orthodontic treatment, the patients are susceptible to dental caries as a result of the bacterial adhesion and biofilm formation around the orthodontic brackets. Prevention of the caries-related biofilm formation is of significance for maintaining both aesthetics and health of the teeth. Herein, the brackets were functionalized with antibacterial activity via coating a layer of non-crosslinked chitosan (CS). We firstly demonstrated the ability of free CS scaffolds (not coated on brackets) to inhibit the formation of Streptococcus mutans biofilms (inhibition rate 94.3 % for CS-0.3 mg) and to eradicate the mature biofilms (biofilm loss rate 99.8 % for CS-1.2 mg). Further, the inhibition of S. mutans biofilm formation on brackets by CS coating was investigated for the first time. As a result, the CS-coated brackets (Br-CS) kept the great biofilm inhibition capacity of free CS scaffolds. In detail, the Br-CS, prepared by immersing brackets in CS solutions (containing 1.0, 2.5, 5.0 and 10 mg/mL CS) and freeze-drying, showed the biofilm inhibition rate of 48.5 %, 88.6 %, 96.4 % and 99.6 %, respectively. In conclusion, coating orthodontic brackets with the non-crosslinked CS is a potential approach for inhibiting biofilm formation and protecting patients from dental caries. [ABSTRACT FROM AUTHOR]

Sr 3.8 Fe 25.7 O 70.4 -chitosan magnetic microparticles (Sr 3.8 Fe 25.7 O 70.4 -CMNs) with a core-shell structure were synthesized, characterized and applied for the removal of two model cationic dyes. The results showed that these magnetic microparticles possess fast adsorption rate and high adsorption efficiency for both crystal violet (CV) and basic red 9 (BR9) at a temperature ranging 30 °C to 40 °C and suitable pH range (pH ≥ 7). The maximum removal efficiency for CV and BR9 attained to 94.5% and 97.5% in 30 min, which was significantly faster and higher than that of chitosan (<50% in 60 min) (P <0.01). And its maximum adsorption capacity for CV and BR9 reached 29.46 mg/g and 32.16 mg/g, respectively. The adsorption process of Sr 3.8 Fe 25.7 O 70.4 -CMNs follows the Langmuir isotherm with a high correlation coefficient (R 2 > 0.97) and the pseudo-second-order model. Additionally, the synthesized Sr 3.8 Fe 25.7 O 70.4 -CMNs were easy to regeneration and reuse, and the removal rate remained above 90% after 5 recycle times. This study would provide a new more environmental friendly material and method for the treatment of wastewater containing toxic dyes. [ABSTRACT FROM AUTHOR]