Efficacy and safety of gut microbiota-based therapies in autoimmune and rheumatic diseases: a systematic review and meta-analysis of 80 randomized controlled trials.

BACKGROUND: Previous randomized controlled trials (RCTs) suggested that gut microbiota-based therapies may be effective in treating autoimmune diseases, but a systematic summary is lacking. METHODS: Pubmed, EMbase, Sinomed, and other databases were searched for RCTs related to the treatment of autoimmune diseases with probiotics from inception to June 2022. RevMan 5.4 software was used for meta-analysis after 2 investigators independently screened literature, extracted data, and assessed the risk of bias of included studies. RESULTS: A total of 80 RCTs and 14 types of autoimmune disease [celiac sprue, SLE, and lupus nephritis (LN), RA, juvenile idiopathic arthritis (JIA), spondyloarthritis, psoriasis, fibromyalgia syndrome, MS, systemic sclerosis, type 1 diabetes mellitus (T1DM), oral lichen planus (OLP), Crohn's disease, ulcerative colitis] were included. The results showed that gut microbiota-based therapies may improve the symptoms and/or inflammatory factor of celiac sprue, SLE and LN, JIA, psoriasis, PSS, MS, systemic sclerosis, Crohn's disease, and ulcerative colitis. However, gut microbiota-based therapies may not improve the symptoms and/or inflammatory factor of spondyloarthritis and RA. Gut microbiota-based therapies may relieve the pain of fibromyalgia syndrome, but the effect on fibromyalgia impact questionnaire score is not significant. Gut microbiota-based therapies may improve HbA1c in T1DM, but its effect on total insulin requirement does not seem to be significant. These RCTs showed that probiotics did not increase the incidence of adverse events. CONCLUSIONS: Gut microbiota-based therapies may improve several autoimmune diseases (celiac sprue, SLE and LN, JIA, psoriasis, fibromyalgia syndrome, PSS, MS, T1DM, Crohn's disease, and ulcerative colitis).

Characteristics of Dialdehyde Cellulose Nanofibrils Derived from Cotton Linter Fibers and Wood Fibers.

Two types of cellulose nanofibrils (CNFs) were isolated from cotton linter fibers and hardwood fibers through mechanical fibrillation methods. The dialdehyde cellulose nanofibrils (DACNFs) were prepared through the periodate oxidation method, and their morphological and structural properties were investigated. The characteristics of the DACNFs during the concentration process were also explored. The AFM analysis results showed that the mean diameters of wood fiber-based CNFs and cotton fiber-based CNFs were about 52.03 nm and 69.51 nm, respectively. However, the periodate oxidation treatment process obviously reduced the nanofibril size and destroyed the crystalline region of the nanofibrils. Due to the high crystallinity of cotton fibers, the cotton fiber-based DACNFs exhibited a lower aldehyde content and suspension stability compared to the wood fiber-based DACNFs. For the concentration process of the DACNF suspension, the bound water content of the concentrated cotton fiber-based DACNFs was lowered to 0.41 g/g, which indicated that the cotton fiber-based DACNFs could have good redispersibility. Both the wood fiber-based and cotton fiber-based DACNF films showed relatively good transmittance and mechanical strength. In addition, to the cotton fiber-based DACNF films had a very low swelling ratio, and the barrier water vapor and oxygen properties of the redispersed cotton fiber-based DACNF films decreased by very little. In sum, this study has demonstrated that cotton fibers could serve as an effective alternative to wood fibers for preparing CNFs, and that cotton fiber-based DACNFs have huge application prospects in the field of packaging film materials due to their stable properties during the concentration process.

Enhancing Mechanical and Antimicrobial Properties of Dialdehyde Cellulose-Silver Nanoparticle Composites through Ammoniated Nanocellulose Modification.

Given the widespread prevalence of viruses, there is an escalating demand for antimicrobial composites. Although the composite of dialdehyde cellulose and silver nanoparticles (DAC@Ag1) exhibits excellent antibacterial properties, its weak mechanical characteristics hinder its practical applicability. To address this limitation, cellulose nanofibers (CNFs) were initially ammoniated to yield N-CNF, which was subsequently incorporated into DAC@Ag1 as an enhancer, forming DAC@Ag1/N-CNF. We systematically investigated the optimal amount of N-CNF and characterized the DAC@Ag1/N-CNF using FT-IR, XPS, and XRD analyses to evaluate its additional properties. Notably, the optimal mass ratio of N-CNF to DAC@Ag1 was found to be 5:5, resulting in a substantial enhancement in mechanical properties, with a 139.8% increase in tensile elongation and a 33.1% increase in strength, reaching 10% and 125.24 MPa, respectively, compared to DAC@Ag1 alone. Furthermore, the inhibition zones against Escherichia coli and Staphylococcus aureus were significantly expanded to 7.9 mm and 15.9 mm, respectively, surpassing those of DAC@Ag1 alone by 154.8% and 467.9%, indicating remarkable improvements in antimicrobial efficacy. Mechanism analysis highlighted synergistic effects from chemical covalent bonding and hydrogen bonding in the DAC@Ag1/N-CNF, enhancing the mechanical and antimicrobial properties significantly. The addition of N-CNF markedly augmented the properties of the composite film, thereby facilitating its broader application in the antimicrobial field.

Sustainable and Scalable Synthesis of 2D Ultrathin Hierarchical Porous Carbon Nanosheets for High-Performance Supercapacitor.

2D carbon nanomaterials such as graphene, carbon nanosheets, and their derivatives, representing the emerging class of advanced multifunctional materials, have gained great research interest because of their extensive applications ranging from electrochemistry to catalysis. However, sustainable and scalable synthesis of 2D carbon nanosheets (CNs) with hierarchical architecture and irregular structure via a green and low-cost strategy remains a great challenge. Herein, prehydrolysis liquor (PHL), an industrial byproduct of the pulping industry, is first employed to synthesize CNs via a simple hydrothermal carbonization technique. After mild activation with NH4 Cl and FeCl3 , the as-prepared activated CNs (A-CN@NFe) display an ultrathin structure (≈3 nm) and a desirable specific surface area (1021 m2 g-1 ) with hierarchical porous structure, which enables it to be both electroactive materials and structural support materials in nanofibrillated cellulose/A-CN@NFe/polypyrrole (NCP) nanocomposite, and thus endowing nanocomposite with impressive capacitance properties of 2546.3 mF cm-2 at 1 mA cm-2 . Furthermore, the resultant all-solid-state symmetric supercapacitor delivers a satisfactory energy storage ability of 90.1 µWh cm-2 at 250.0 µW cm-2 . Thus, this work not only opens a new window for sustainable and scalable synthesis of CNs, but also offers a double profits strategy for energy storage and biorefinery industry.

Dialdehyde Cellulose Solution as Reducing Agent: Preparation of Uniform Silver Nanoparticles and In Situ Synthesis of Antibacterial Composite Films with High Barrier Properties.

The demand for antimicrobial materials is gradually increasing due to the threat of infections and diseases caused by microorganisms. Silver nanoparticles (AgNPs) are widely used because of their broad-spectrum antimicrobial properties, but their synthesis methods are often environmentally harmful and AgNPs difficult to isolate, which limits their application in several fields. In this study, an aqueous solution of dialdehyde cellulose (DAC) was prepared and used as a reducing agent to synthesize AgNPs in an efficient and environmentally friendly process. The synthesized AgNPs can be easily separated from the reducing agent to expand their applications. In addition, the AgNPs were immobilized in situ on dialdehyde cellulose to form antibacterial composite films. The results showed that the prepared silver nanoparticles were mainly spherical and uniformly dispersed, with an average size of about 25 nm under optimal conditions. Moreover, the dialdehyde cellulose-nanosilver (DAC@Ag) composite films had excellent mechanical properties, positive transparency, ultraviolet-blocking properties, and effective antibacterial activity against E. coli and S. aureus. Notably, the composite films exhibited excellent oxygen and water vapor barrier properties, with WVT and ORT of 136.41 g/m2·24 h (30 °C, 75% RH) and <0.02 cm3/m2·24 h·0.1 MPa (30 °C, 75% RH), respectively, better than commercial PE films. Hence, this study not only provides an environmentally friendly method for the preparation of silver nanoparticles, but also offers a simple and novel strategy for the in situ synthesis of silver-loaded antibacterial composite films.

Regulatory Mechanism of Opposite Charges on Chiral Self-Assembly of Cellulose Nanocrystals.

The charge plays an important role in cellulose nanocrystal (CNC) self-assembly to form liquid crystal structures, which has rarely been systematically explored. In this work, a novel technique combining atomic force microscopy force and atomistic molecular dynamics simulations was addressed for the first time to systematically investigate the differences in the CNC self-assembly caused by external positive and negative charges at the microscopic level, wherein sodium polyacrylate (PAAS) and chitosan oligosaccharides (COS) were used as external positive and negative charge additives, respectively. The results show that although the two additives both make the color of CNC films shift blue and eventually disappear, their regulatory mechanisms are, respectively, related to the extrusion of CNC particles by PAAS and the reduction in CNC surface charge by COS. The two effects both decreased the spacing between CNC particles and further increased the cross angle of CNC stacking arrangement, which finally led to the color variations. Moreover, the disappearance of color was proved to be due to the kinetic arrest of CNC suspensions before forming chiral nematic structure with the addition of PAAS and COS. This work provides an updated theoretical basis for the detailed disclosure of the CNC self-assembly mechanism.

Switchable Circularly Polarized Signals with High Asymmetric Factor Triggered by Dual Photonic Bandgap Structure.

Currently, the smart photonic materials that can switch circularly polarized signals in real-time have attracted extensive attention due to numerous potential applications in information storage and photonics displays. However, the dynamically reversible switching of circularly polarized signals requires precise structural reconfiguration, which is rarely achieved in traditional biomaterials. Herein, a dual photonic bandgap (PBG) structure is constructed based on the optical propagation principle of cellulose-based photonic crystals, enabling the flexible switching of the intensity, wavelength, and direction of circularly polarized luminescence (CPL). By adjusting the fluorescence intensity and the matching degree of chiral structure, the asymmetric factor value of dual PBG structure is up to -1.47, far exceeding other cellulose-based materials. Importantly, it is demonstrated that dual CPL emission can be efficiently induced by two different PBGs, opening a new approach for on-demand switching of single and dual CPL emission. In addition, the dual PBG structure exhibits dual circularly polarized reflected signals under the circular polarizer, which perfectly embodies the applicability of multiple encryptions in QR codes. This work provides new insights into the real-time manipulation of circularly polarized signals by chiral photonic materials.

Boosting Alkaline Hydrogen and Oxygen Evolution Kinetic Process of Tungsten Disulfide-Based Heterostructures by Multi-Site Engineering.

Alkaline water electrolysis is an advanced technology for scalable H2 production using surplus electricity from intermittent energy sources, but it remains challenging for non-noble electrocatalysts to split water into hydrogen and oxygen efficiently, especially for tungsten disulfide (WS2 )-based catalysts. Density functional theory calculations in combination with experimental study are used to establish a multi-site engineering strategy for developing robust WS2 -based hybrid electrocatalyst on mesoporous bimetallic nitride (Ni3 FeN) nanoarrays for bifunctional water splitting. This ingenious design endows the catalyst with numerous edge sites chemically bonded with the conductive scaffold, which are favorable for water dissociation and hydrogen adsorption. Benefiting from the synergistic advantages, the N-WS2 /Ni3 FeN hybrid exhibits exceptional bifunctional properties for hydrogen and oxygen evolution reactions (HER and OER) in base with excellent large-current durability, requiring 84 mV to afford 10 mA cm-2 for HER, and 240 mV at 100 mA cm-2 for OER, respectively. Assembling the catalytic materials as both the anode and cathode to construct an electrolyzer, it is actualized very good activities for overall water splitting with only 1.5 V to deliver 10 mA cm-2 , outperforming the IrO2 (+) //Pt(-) coupled electrodes and many non-noble bifunctional electrocatalysts thus far. This work provides a promising avenue for designing WS2 -based heterogeneous electrocatalysts for water electrolysis.

Engineering In-Plane Nickel Phosphide Heterointerfaces with Interfacial sp HP Hybridization for Highly Efficient and Durable Hydrogen Evolution at 2 A cm-2.

The catalytic hydrogen-evolving activities of transition-metal phosphides are greatly related to the phosphorus content, but the physical origin of performance enhancement remains ambiguous, and tuning the catalytic activity of nickel phosphides (NiP2 /Ni5 P4 ) remains challenging due to unfavorable H* adsorption. Here, a strategy is introduced to integrate P-rich NiP2 and P-poor Ni5 P4 into in-plane heterostructures by anion substitution, in which P atoms at the in-plane interfaces perform as active sites to adsorb H* and thus facilitate the hydrogen evolution reaction (HER) process via modulating the electronic structure between NiP2 and Ni5 P4 . Consequently, the NiP2 /Ni5 P4 hybrid exhibits an outstanding hydrogen-evolving activity, requiring only 30 and 76 mV to afford 10 and 100 mA cm-2 in acid, respectively. It surpasses most of the earth-abundant electrocatalysts thus far, and is comparable to Pt catalysts (30/72 mV at 10/100 mA cm-2 ). Particularly, it can run smoothly at large current density and only requires 247 mV to reach 2000 mA cm-2 . Detailed theoretical calculations reveal that its exceptional activity stems from the moderate overlap of density states between P 2p and H 1s orbitals, thus optimizing the H*-adsorption strength. This work highlights a new avenue toward the fabrication of robust non-noble electrocatalysts by constructing in-plane heterojunctions.

Chiral Photonic Liquid Crystal Films Derived from Cellulose Nanocrystals.

As a nanoscale renewable resource derived from lignocellulosic materials, cellulose nanocrystals (CNCs) have the features of high purity, high crystallinity, high aspect ratio, high Young's modulus, and large specific surface area. The most interesting trait is that they can form the entire films with bright structural colors through the evaporation-induced self-assembly (EISA) process under certain conditions. Structural color originates from micro-nano structure of CNCs matrixes via the interaction of nanoparticles with light, rather than the absorption and reflection of light from the pigment. CNCs are the new generation of photonic liquid crystal materials of choice due to their simple and convenient preparation processes, environmentally friendly fabrication approaches, and intrinsic chiral nematic structure. Therefore, understanding the forming mechanism of CNCs in nanoarchitectonics is crucial to multiple fields of physics, chemistry, materials science, and engineering application. Herein, a timely summary of the chiral photonic liquid crystal films derived from CNCs is systematically presented. The relationship of CNC, structural color, chiral nematic structure, film performance, and applications of chiral photonic liquid crystal films is discussed. The review article also summarizes the most recent achievements in the field of CNCs-based photonic functional materials along with the faced challenges.

Involvement of Connexin40 in the Protective Effects of Ginsenoside Rb1 Against Traumatic Brain Injury.

Ginsenosides are the major active components of ginseng, which have been proven to be effective in therapies for neurodegenerative diseases. Ginsenoside Rb1 (GS-Rb1) is the most abundant among all the identified ginsenosides and has been shown to exert neuroprotective effects, although the underlying molecular mechanisms remain unclear. Connexins are a family of transmembrane proteins that form gap junctions, which are important for diffusion of cytosolic factors such as ions and second messenger signaling molecules. Previous studies have shown that a subset of connexin proteins is involved in neuroprotection. We investigated the protective effects of GS-Rb1 against traumatic brain injury (TBI) and the potential mechanism using TBI mouse model. We discovered that TBI-induced brain injury and up-regulation of connexin40 (Cx40) protein expression as early as 6 h post-TBI, which was reversed by administration of GS-Rb1. In addition, we found that the protective effects of GS-Rb1 are dose and time dependent and are partially mediated through phosphorylation of ERK1/2 signaling pathway, as evidenced by the abolishment of GS-Rb1-mediated elevation of p-ERK1/2 expression and inhibition of Cx40 expressions when ERK inhibitor U0126 was used. Our study provides evidence that Cx40 is implicated in TBI-induced brain injuries, and GS-Rb1 exerts neuroprotective activity against TBI involving down-regulation of Cx40 expression.

Protective effect of ginsenoside Rb1 on integrity of blood-brain barrier following cerebral ischemia.

Ginsenosides, the major bioactive compounds in ginseng root, have been found to have antioxidant, immunomodulatory, and anti-inflammatory activities. In the present study, we sought to investigate whether and how ginsenoside Rb1 (GS-Rb1), the most abundant ginsenoside, can protect blood-brain barrier (BBB) integrity following cerebral ischemia in middle cerebral artery occlusion (MCAO) animal model. ICR mice underwent MCAO and received GS-Rb1 by intraperitoneal injection at 3 h after reperfusion. We evaluated infarction, neurological scores, brain edema, Evans blue (EB) extravasation, and tight junction protein expression at 48 h after MCAO. We further examined whether GS-Rb1 protected BBB integrity by suppressing post-ischemic inflammation-induced activity of matrix metalloproteinase-9 (MMP-9) and nicotinamide adenine dinucleotide phosphate oxidase (NOX). First, GS-Rb1 decreased infarction and improved neurological deficits in MCAO animals. In addition, GS-Rb1 reduced EB extravasation and brain edema and preserved expression of tight junction proteins in the ischemic brain. Moreover, GS-Rb1 inhibited expression of pro-inflammatory factors including nitric oxide synthase and IL-1ß, but increased expression of anti-inflammatory markers arginase 1 and IL-10 in the ischemic brain. Consistently, GS-Rb1 attenuated ischemia-induced expression and activity of MMP9. Finally, GS-Rb1 reduced NOX-4 mRNA expression and NOX activity in ischemic brain. These results suggest that GS-Rb1 protects loss of BBB integrity in ischemic stroke by suppressing neuroinflammation induction of MMP-9 and NOX4-derived free radicals, and indicate its potential for treating brain injuries, such as ischemia and stroke.

Development of high-barrier composite films for sustainable reduction of non-biodegradable materials in food packaging application.

Widely employed petroleum-based food packaging materials have inflicted irreparable harm on ecosystems, primarily stemming from their non-biodegradable attributes and recycling complexities. Inspired by natural nacre with a layered aragonite platelet/nanofiber/protein multi-structure, we prepared high-barrier composite films by self-assembly of cellulose nanofibrils (CNF), cellulose nanocrystals (CNC), montmorillonite (MMT), polyvinyl alcohol (PVA) and alkyl ketene dimer (AKD). The composite films demonstrated outstanding barrier properties with oxygen vapor transmission of 0.193 g·mm·m-2·day-1 and water vapor transmission rates of 0.062 cm3·mm·m-2·day-1·0.1 MPa-1, which were significantly lower than those of most biomass-degradable packaging materials. Additionally, the impacts of mixing nanocellulose with various aspect ratios on the tensile strength and folding cycles of the films were examined. The exceptional resistance of the composite films to oil and water provides a novel and sustainable approach to reduce non-biodegradable plastic packaging.

Water-soluble silver nanoclusters with multicolor fluorescence generated by dialdehyde nanofibrillated cellulose for biological imaging.

Water-soluble silver nanoclusters (AgNCs) as a new type of fluorescent material have attracted much attention for their remarkable optical properties and excellent cytocompatibility. However, it is still challenging to synthesize water-soluble AgNCs with good cytocompatibility and excellent fluorescence. Herein, the dialdehyde nanofibrillated cellulose (DANFC)- reduced water-soluble AgNCs capped by glutathione (GSH) with tunable fluorescence emissions were first reported. The DANFC provides a mild reduction environment and crystal growth system for the coordination between silver ions and GSH compared to conventional methods using strong reducing agents. The AgNCs with intense red fluorescence (R-AgNCs@GSH, size ∼2.24 nm) and green fluorescence (G-AgNCs@GSH, size ∼1.93 nm) were produced by varying the ratios of silver sources and ligands, and could maintain stable fluorescence intensity over 6 months. Moreover, the CCK-8 study demonstrated that the R-AgNCs@GSH and G-AgNCs@GSH reduced by DANFC of excellent cytocompatibility (cell viability >90 %) and enable precise multicolor intracellular imaging of Hela cells in 1 h. This work proposes a novel method to synthesize water-soluble AgNCs with tunable fluorescence emission at room temperature based on the classical silver- mirror reaction (SMR) using DANFC as reducing agent, and the synthesized fluorescent AgNCs have great potential as novel luminescent nanomaterials in biological research.

In Situ Regulating Cobalt/Iron Oxide-Oxyhydroxide Exchange by Dynamic Iron Incorporation for Robust Oxygen Evolution at Large Current Density.

The key dilemma for green hydrogen production via electrocatalytic water splitting is the high overpotential required for anodic oxygen evolution reaction (OER). Co/Fe-based materials show superior catalytic OER activity to noble metal-based catalysts, but still lag far behind the state-of-the-art Ni/Fe-based catalysts probably due to undesirable side segregation of FeOOH with poor conductivity and unsatisfied structural durability under large current density. Here, a robust and durable OER catalyst affording current densities of 500 and 1000 mA cm-2 at extremely low overpotentials of 290 and 304 mV in base is reported. This catalyst evolves from amorphous bimetallic FeOOH/Co(OH)2 heterostructure microsheet arrays fabricated by a facile mechanical stirring strategy. Especially, in situ X-ray photoelectron spectroscopy (XPS) and Raman analysis decipher the rapid reconstruction of FeOOH/Co(OH)2 into dynamically stable Co1-x Fex OOH active phase through in situ iron incorporation into CoOOH, which perform as the real active sites accelerating the rate-determining step supported by density functional theory calculations. By coupling with MoNi4 /MoO2 cathode, the self-assembled alkaline electrolyzer can deliver 500 mA cm-2 at a low cell voltage of 1.613 V, better than commercial IrO2 (+) ||Pt/C(-) and most of reported transition metal-based electrolyzers. This work provides a feasible strategy for the exploration and design of industrial water-splitting catalysts for large-scale green hydrogen production.

Protective effects of degraded Bletilla striata polysaccharides against UVB-induced oxidative stress in skin.

The Bletilla striata polysaccharides (BSP) extracted through alkali-assisted method exhibit significant antioxidant activity, but its bioaccessibility was inadequate due to its tightly filamentous reticulation structure and high molecular weight. The anti-photoaging and anti-melanogenesis effects of degraded BSP (DBSPs) against UVB-induced oxidative stress on the skin were investigated. The molecular weights of the DBSPs were reduced to 153.94 kDa, 66.96 kDa, and 15.54 kDa from an initial value of 298.82 kDa. The degradation treatment altered the branched chain structure of the DBSPs, while the backbone structure, triple-helix structure, and crystallinity remained. DBSPs with a lower molecular weight exhibit better in vitro antioxidant activity. DBSPs did not show cytotoxicity to HSF cells but inhibited B16F10 cell proliferation. The addition of DBSPs protected HSF and B16F10 cells from oxidative stress and reduced ROS levels, B16F10 melanin content, and B16F10 tyrosinase activity after UVB damage, but DBSP-10 particles were slightly less effective due to aggregation. In contrast, DBSP-5 demonstrated effectiveness in reducing MDA levels in cells stressed by oxidative stress, increased total antioxidant capacity, and inhibited melanogenesis in B16F10, suggesting that DBSP-5 has potential as a topical therapeutic agent for the treatment of skin diseases associated with oxidative stress.

Ultrastrong Nanopapers with Aramid Nanofibers and Silver Nanowires Reinforced by Cellulose Nanofibril-Assisted Dispersed Graphene Nanoplates for Superior Electromagnetic Interference Shielding.

High-strength, lightweight, ultrathin, and flexible electromagnetic interference (EMI) shielding materials with a high shielding effectiveness (SE) are essential for modern integrated electronics. Herein, cellulose nanofibrils (CNFs) are employed to homogeneously disperse graphene nanoplates (GNPs) into an aramid nanofiber (ANF) network and silver nanowire (AgNW) network, respectively, producing high-performance nanopapers. These nanopapers, featuring nacre-mimetic microstructures and layered architectures, exhibited high tensile strength (601.11 MPa) and good toughness (103.56 MJ m-3) with a thickness of only 24.58 µm. Their specific tensile strength reaches 447.59 MPa·g-1·cm3, which is 1.74 times that of titanium alloys (257 MPa·g-1·cm3). The AgNW/GNP composite conductive layers exhibit an electrical conductivity of 12010.00 S cm-1, providing the nanopapers with great EMI shielding performance, achieving an EMI SE of 63.87 dB and an EMI SE/t of 25978.80 dB cm-1. The nanopapers also show reliable durability, retaining a tensile strength of 500.96 MPa and an EMI SE of 57.59 dB after 120,000 folding cycles. Additionally, they have a good electrical heating performance with a fast response time, low driving voltage, effective deicing capability, and reliable heating capacity in water. This work presents a strategy to develop a high-performance nanopaper, showing great potential for applications in electromagnetic compatibility, national defense, smart electronics, and human health.

Acid-catalyzed phenolation of lignin with tea polyphenol: Enhancing uv resistance and oxidation resistance for potential applications.

The rapid development of the industry has led to the destruction of the earth's ozone layer, resulting in an increasingly serious problem of excessive ultraviolet radiation. Exploring effective measures to address these problems has become a hot topic. Lignin shows promise in the design and preparation of anti-ultraviolet products due to its inherent properties. However, it is important to investigate way to enhance the reactivity of lignin and determine its application form in related products. In this study, phenolic reactions with tea polyphenols were conducted through acid-catalyzed conversion, utilizing organic solvent lignin as the primary material. The phenolic hydroxyl content of the original lignin increased significantly by 218.8 %, resulting in notable improvements in UV resistance and oxidation resistance for phenolic lignin. Additionally, micro-nanocapsule emulsions were formed using phenolic lignin particles as surfactants through ultrasonic cavitation with small-molecule sunscreens. A bio-based sunscreen was prepared with phenolated lignin micro-nanocapsules as the active ingredient, achieving an SPF 100.2 and demonstrating excellent stability. The sunscreen also exhibited strong antioxidant properties and impermeability, ensuring user safety. This research offers a current solution for improving the application of lignin in sunscreens while also broadening the potential uses of plant-based materials in advanced functional products.

Skin healthcare protection with antioxidant and anti-melanogenesis activity of polysaccharide purification from Bletilla striata.

In this study, we investigated the structural characterization and biological activities of Bletilla striata polysaccharides (BSPs) for their role as antioxidants and anti-melanogenesis agents in skin healthcare protection. Three neutral polysaccharides (BSP-1, BSP-2, and BSP-3) with molecular weights of 269.121 kDa, 57.389 kDa, and 28.153 kDa were extracted and purified. Their structural characteristics were analyzed by ion chromatography, GC-MS, and 1D/2D NMR. The results showed that BSP-1, which constitutes the major part of BSPs, was composed of α-D-Glcp, ß-D-Glcp, ß-D-Manp, and 2-O-acetyl-ß-D-Manp, with the branched-chain accompanied by ß-D-Galp and α-D-Glcp. BSP-1, BSP-2, and BSP-3 can enhance the total antioxidant capacity of skin fibroblasts with non-toxicity. Meanwhile, BSP-1, BSP-2, and BSP-3 could significantly inhibit the proliferative activity of melanoma cells. Among them, BSP-1 and BSP-2 showed more significance in anti-melanogenesis, tyrosinase inhibition activity, and cell migration inhibition. BSPs have effective antioxidant capacity and anti-melanogenesis effects, which should be further emphasized and developed as skin protection components.

Ultra-strong, nonfreezing, and flexible strain sensors enabled by biomass-based hydrogels through triple dynamic bond design.

Biomass-based hydrogels have displayed excellent potential in flexible strain sensors due to their adequacy, biocompatibility, nontoxic and degradability. Nevertheless, their inferior mechanical properties, particularly at cryogenic temperatures, impeded their extensive utilization. Herein, we reported a rationally designed strain sensor fabricated from a gelatin and cellulose-derived hydrogel with superior mechanical robustness, cryogenic endurance, and flexibility, owing to a triple dynamic bond strategy (TDBS), namely the synergistic reinforcement among potent hydrogen bonds, imine bonds, and sodium bonds. Beyond conventional sacrificing bonds consisting of hydrogen bonds, dynamic covalent bonds and coordinate bonds, synergetic triple dynamic bonds dominated by strong hydrogen bonds and assisted by imine and sodium bonds with higher strength can dissipate more mechanical energy endowing the hydrogel with 38-fold enhancement in tensile strength (6.4 MPa) and 39-fold improvement in toughness (2.9 MPa). We further demonstrated that this hydrogel can work as a robust and biodegradable strain sensor exhibiting remarkable flexibility, broad detection range, considerable sensitivity and excellent sensing stability. Furthermore, owing to the improved nonfreezing performance achieved from incorporating sodium salts, the sensor delivered outstanding sensing properties under subzero conditions such as -20 and -4 °C. It is anticipated that the TDBS can create diverse high-performance soft-electronics for broad applications in human-machine interfaces, energy and healthcare.