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Chronic cutaneous wounds present a significant challenge for healthcare providers globally, with the risk of bacterial infections emerging as a particularly concerning issue. There is an increasing need to employ a combination of diverse antibacterial strategies to address infections comprehensively in chronic wounds. This study introduces a highly efficient antibacterial platform that encapsulates the NO precursor (BNN6) into β-cyclodextrin-modified hemin-bearing polydopamine nanoparticles called NO/CHPDA. These nanoparticles are seamlessly integrated into a hydrogel composite comprised of L-arginine grafted chitosan (Arg-CS) and oxide dextrans (oDex). The amalgamation of photothermal therapy (PTT), chemodynamic therapy (CDT), and nitric oxide (NO) antibacterial strategies within the NO/CHPDA@Arg-CS/oDex nanocomposite hydrogel demonstrates a synergistic and highly effective capacity to eradicate bacteria and accelerate the wound healing process in vivo. Remarkably, this nanocomposite hydrogel maintains excellent biocompatibility and induces minimal side effects. The resulting nanocomposite hydrogel represents a promising therapeutic solution for treating bacterial infections in wound healing applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Tetrahydrocurcumin-hyaluronic acid (THC-HA) conjugate was synthesized in order to improve the bioaccessibility of tetrahydrocurcumin (THC). The successful conjugation was confirmed by the results from 1H-nuclear magnetic resonance (1H NMR), Differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Bioaccessibility enhancement from the THC-HA conjugate compared to the free crystalline THC suspension was demonstrated by the results from ex vivo Franz diffusion cell using small intestine from porcine and in vitro TNO dynamic gastrointestinal model-1 (TIM-1). Additionally, in vitro release was studied, and the integrity of the conjugate in both simulated gastric and intestinal conditions was found to maintain for up to 4 h. Mucoadhesive assay and rheological results indicated that the mucoadhesive property of THC-HA, in combination with the aqueous solubility enhancement, might contribute to the increased bioaccessibility. This study provides a promising approach to enhance the bioaccessibility of tetrahydrocurcumin through the innovative conjugation with hyaluronic acid. [Display omitted] [ABSTRACT FROM AUTHOR]

The emphasis of this study lies in that we present a novel fluorescence scanning approach to evaluate the antioxidant capacity of Fritillaria ussuriensis polysaccharide-zinc (FUP-Zn) complex. FUP was extracted successfully, and the corresponding FUP-Zn complexes with different substitution degrees were obtained after modified chemically with ZnCl 2. The physiochemical characteristics of the as-prepared samples were determined by ultraviolet-visible spectroscopy, infrared spectroscopy, X-ray powder diffraction, scanning electron microscope, energy dispersive spectrum, thermo gravimetric-differential thermal analyses and etc. , and these characterization results confirmed the successful synthesis of FUP-Zn complexes with good stability. The scavenging ability investigation of FUP-Zn complexes towards hydroxyl radicals and superoxide anion radicals carried out by us has revealed that the integration of FUP and Zn greatly enhanced the antioxidant activity due to the synergistic effect and larger pore size of FUP-Zn complexes, and the antioxidant activity of FUP-Zn complex with different substitution degrees is heavily dependent on the amount of Zn. This study indeed provides vital theoretical basis for the promising antioxidant and zinc supplement evaluation from more novel polysaccharide-zinc complexes with suited Zn amount. • The antioxidant activities of FUP-Zn- n complexes towards •OH and O 2 −• were evaluated by a new fluorescent scanning method. • Fritillaria ussuriensis Maxim polysaccharide-zinc (FUP-Zn- n) complexes with distinct Zn contents were prepared for the first time. • The structural and morphological characterizations of FUP-Zn- n complexes were performed in detail using various methods. • The underlying antioxidant mechanism of FUP-Zn- n complexes was elaborated in vitro. • FUP-Zn- n complexes could be applied as potential candidate for next generation antioxidant and zinc supplement. [ABSTRACT FROM AUTHOR]

In recent years, natural resources have proven to be tremendous sources of glycoproteins. As biological macromolecules, glycoproteins are essential to the growth and development of organisms, and have attracted increasing attention around the world. This review summarized and discussed the development of glycoproteins from natural resources, including isolation methods, purification processes, structural features and biological activities. Generally, the vast majority of glycoproteins can be isolated by hot water extraction followed by purification through gel filtration chromatography. Combined with component analysis, the physicochemical properties of glycoproteins are studied by using several spectroscopic techniques such as ultraviolet-visible (UV–visible), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR). Moreover, natural glycoproteins possess various remarkable biological activities, including anti-tumor, anti-oxidant, anti-coagulant and anti-microbial activities. The content of this review will provide a theoretical basis for the research on related glycoproteins and give a perspective on the use of these medical resources. [ABSTRACT FROM AUTHOR]

The structure and properties of lignin can vary depending on the type of lignocellulosic biomass it comes from and the separation techniques used, and also affects its suitability for different applications. In this work, the structure and properties of lignin isolated from moso bamboo, wheat straw, and poplar wood by different treatment processes were compared. Results show that deep eutectic solvent (DES) extracted lignin exhibits well-preserved structures (including β-O-4, β–β, and β-5 linkages), a low molecular weight (M n = 2300–3200 g/mol), and relatively homogeneous lignin fragments (1.93 < PDI < 2.33) compared to dealkaline lignin (DL) and milled wood lignin (MWL). Besides, lignin samples extracted by DES have a regular nanostructure, higher carbon residue content (>40 %), and excellent antioxidant properties (the free radical scavenging index >20). Among the three types of biomass, the structural destruction of lignin in straw is the most obvious, which is due to the degradation of β-O-4 and β-β linkages during DES treatment. These findings can contribute to a better understanding of the structural changes that occur in various treatment processes from different lignocellulosic biomass, and help maximize the targeted development of their applications based on the characteristics of lignin. [Display omitted] • Different lignins were prepared from various biomass by different processes. • Various lignin structural and property characteristics were elaborately analyzed. • DESs isolated lignin showed nanostructures structure and antioxidant properties. • Various processes provided a wide vision for better use of lignin in future biorefineries. [ABSTRACT FROM AUTHOR]

It is highly desirable to develop novel multifunctional wound dressing materials capable of delivering active molecules capable of resolving bacterial infections and replenishment of appropriate growth factors for bacteria-infected wound healing. Polysaccharides have numerous biomedical benefits and have been widely used to construct biomaterial scaffolds. Herein, multifunctional chitosan/alginate hydrogel decorated with β-cyclodextrin (β-CD) modified polydopamine (PDA)-bioactive glass (BG) nanoparticles (NPs) integrating photothermal performance and nitric-oxide release activities for the treatment of bacterially infected wounds is presented. As the NO precursor N , N ′-di-sec-butyl-N,N′-dinitroso-1,4-phenylenediamine (BNN6) encapsulated into the hydrophobic cavity of β-CD on the PDA-coated BG NPs, the resultant NO@CD-PDA/BG NPs, are imparted with the feature of NIR triggered NO release and desired PTT/NO synergetic antibacterial effects. Furthermore, the release of NO, Ca, and Si ions from the NO@CD-PDA/BG NPs, has the benefit of regulating inflammation, promoting fibroblast proliferation, and stimulating angiogenesis. Besides, the chitosan/alginate hydrogel scaffolds provided a suitable microenvironment to accelerate wound healing. By applying the multifunctional chitosan/alginate nanocomposite hydrogel to S. aureus -infected full-thickness skin defect mouse model, the authors demonstrated that chitosan/alginate nanocomposite hydrogel has multiple functions in preventing bacterial infections, accelerating angiogenesis and wound regeneration, indicating promising application in wound healing. [Display omitted] [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]

A novel acidic polysaccharide named SSPA50–1 was isolated from Scapharca subcrenata using a simulated gastric fluid extraction method. SSPA50–1 is a heteropolysaccharide with an average molecular weight of 44.7 kDa that is composed of galacturonic acid, glucose, galactose, mannose, ribose, rhamnose, fucose, xylose and arabinose at a molar ratio of 1.00:5.40:9.04:3.10:1.59:4.01:2.10:2.21:2.28. The structural characterization based on the methylation and 1D/2D NMR analyses indicated that SSPA50–1 is composed of →3)- β -L-Rha p -(1→, →3)- β -L-2-O-Me-Fuc p -(1→, →2)- α -D-Xyl p -(1→, →5)- α -L-Ara f -(1→, →3)- β -D-Gal p -(1→, →6)- α -D-Glc p -(1→, →3,4)- β -D-Man p -(1→, →3,4)- β -D-Gal p -(1→, β -D-Rib f -(1→, α -D-Glc p -(1→, and α -D-GalA p 6Me-(1→. Furthermore, SSPA50–1 possessed potent immunoregulatory activity by enhancing the phagocytosis and NO, iNOS, TNF- α and IL-6 secretion capacity of RAW264.7 cells. Otherwise, SSPA50–1 significantly promoted the proliferation of splenic lymphocytes and RAW264.7 macrophages. These results indicated that SSPA50–1 could be developed as a potential ingredient for immunostimulatory agents. • The novel acidic Scapharca subcrenata polysaccharide (SSPA50–1) was isolated. • SSPA50–1 is a heteropolysaccharide that composed of 9 types of monosaccharide. • GalA was first found in the polysaccharides of S. subcrenata. • SSPA50–1 promoted the proliferation of RAW264.7 macrophages and splenocytes. • SSPA50–1 increased the secretion of NO, IL-6 and TNF- α in RAW264.7 cells. [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]

The development of environmental-friendly antibacterial agents with high efficiency and low cost has become the focus of attention. In this work, the Ag nanoparticles doped into chitosan (Ag NPs-CS) were synthesized by a green and facile method, and the samples were characterized by UV–Vis spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The antibacterial tests implied that Ag NPs-CS obtained from glucose (G-Ag NPs-CS) exhibited the excellent antimicrobial activities against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) microbes. Besides, the utilization of antibacterial agents in polymeric materials plays an significant role in healthy living. The aim is to impart the antibacterial properties and maintain/improve the mechanical properties. Therefore, the G-Ag NPs-CS with 5 wt% Ag was chosen as the optimal additive to endow polypropylene with antimicrobial activity via a simple melt blending method. The results demonstrated that the suppression of bacteria proliferation was enhanced with increasing the amount of antibacterial agent, and the microorganisms were almost killed when the content reached to 8 wt%. Meanwhile, the considerable improvement in elastic modulus and impact strength along with a slight decrease of elongation at break provided the evidence that Ag NPs-CS/PP nanocomposites were the promising candidate for practical applications. Unlabelled Image [ABSTRACT FROM AUTHOR]

Nanoscale metal–organic frameworks (NMOFs) have attracted considerable attention for controlled drug delivery. However, the interaction between nanoparticles and the biological macromolecules of physiological system must be valued because the formed protein corona will endow NMOFs with new biorecognition properties. In this study, we carried out detailed protein adsorption studies in vitro and cell uptake tests of HeLa cells for nanospherical Uio66 and nanooctahedral Uio67. Uio67 with higher binding constants to human serum albumin needed to combine more protein molecules to achieve colloidal stability state than that needed by Uio66, and this phenomenon led Uio67 to aggregate under the same incubation condition due to the formation of a single-layer protein. Uio67 also induced an evident conformation change in protein to stabilize the combination. In particular, the cell uptake efficiencies of the two systems showed a significant thickness dependence on the protein corona. When samples incubated in 10% fetal bovine serum (FBS), the intracellular rate was the highest for both systems, but the rate was not proportional to the FBS concentration. Results of this work are important to the development of the considerable potential NMOFs-based medicals and also provide additional insight into protein corona. Unlabelled Image • Distinct morphologies impacted on surface chemistry and cell uptake differently. • Cell uptake efficiencies showed thickness dependence on the protein corona. • Uio67 needed to combine more protein to achieve the colloidal stability state • HSA experienced different degrees conformation change to stabilize the combination. [ABSTRACT FROM AUTHOR]

Abstract: Five polysaccharides from unprocessed Chinese angelica (UCAP), parched one with alcohol (ACAP), soil (SCAP), sesame oil (OCAP) and parched into charred (CCAP) were extracted and purified. Their structures were identified by Fourier transform-infrared spectroscopy (FT-IR), compositions were analyzed by gas chromatography–mass spectrometry (GC–MS) and antioxidative activities were compared by determining MDA contents and SOD activities of liver tissue in mice damaged with CCl4 after gavage. The results showed that the FT-IR spectra of CCAP and OCAP displayed lower transmittance at around 1050cm−1 in comparison with that of UCAP. Five polysaccharides were all composed of rhamnose, arabinose, mannose, glucose and galactose. In CCAP, ACAP, OCAP and SCAP, the proportions of arabinose were significantly increased in comparison with that of UCAP. The SOD activities in CCAP and SCAP groups were significantly enhanced, and MDA contents in CCAP, OCAP and SCAP groups were significantly decreased as compared with UCAP group. This indicated that processing could change the structure, composition and enhance antioxidative activity of polysaccharide in Chinese angelica, and CCAP possessed the strongest antioxidative activity. [Copyright &y& Elsevier]

Corrigendum to "Characterization and antioxidative activities of polysaccharide in Chinese angelica and its processed products" [Int. J. Biol. Macromol. [Extracted from the article]