Fully Printed Multilayer Ceramic Capacitors Based on High-k Perovskite Nanosheets.

Printing technology enables the integration of chemically exfoliated perovskite nanosheets into high-performance microcapacitors. Theoretically, the capacitance value can be further enhanced by designing and constructing multilayer structures without increasing the device size. Yet, issues such as interlayer penetration in multilayer heterojunctions constructed using inkjet printing technology further limit the realization of this potential. Herein, a series of multilayer configurations, including Ag/(Ca2NaNb4O13/Ag)n and graphene/(Ca2NaNb4O13/graphene)n (n = 1-3), are successfully inkjet-printed onto diverse rigid and flexible substrates through optimized ink formulations, inkjet printing parameters, thermal treatment conditions, and rational multilayer structural design using high-k perovskite nanosheets, graphene nanosheets and silver. The dielectric performance is optimized by fine-tuning the number of dielectric layers and modifying the electrode/dielectric interface. As a result, the graphene/(Ca2NaNb4O13/graphene)3 multilayer ceramic capacitors exhibit a remarkable capacitance density of 346 ± 12 nF cm-2 and a high dielectric constant of 193 ± 18. Additionally, these devices demonstrate moderate insulation properties, flexibility, thermal stability, and chemical sensitivity. This work shed light on the potential of multilayer structural design in additive manufacturing of high-performance 2D material-based ceramic capacitors.

Modulating the d-Band Center of RuO2 via Ni Incorporation for Efficient and Durable Li-O2 batteries.

Rechargeable Li-O2 batteries (LOBs) are considered as one of the most promising candidates for new-generation energy storage devices. One of major impediments is the poor cycle stability derived from the sluggish reaction kinetics of unreliable cathode catalysts, hindering the commercial application of LOBs. Therefore, the rational design of efficient and durable catalysts is critical for LOBs. Optimizing surface electron structure via the negative shift of the d-band center offers a reasonable descriptor for enhancing the electrocatalytic activity. In this study, the construction of Ni-incorporating RuO2 porous nanospheres is proposed as the cathode catalyst to demonstrate the hypothesis. Density functional theory calculations reveal that the introduction of Ni atoms can effectively modulate the surface electron structure of RuO2 and the adsorption capacities of oxygen-containing intermediates, accelerating charge transfer between them and optimizing the growth pathway of discharge products. Resultantly, the LOBs exhibit a large discharge specific capacity of 19658 mA h g-1 at 200 mA g-1 and extraordinary cycle life of 791 cycles. This study confers the concept of d-band center modulation for efficient and durable cathode catalysts of LOBs.

Tumour necrosis factor α regulates the miR-27a-3p-Sfrp1 axis in a mouse model of osteoporosis.

Osteoporosis is a metabolic bone disease that involves gradual loss of bone density and mass, thus resulting in increased fragility and risk of fracture. Inflammatory cytokines, such as tumour necrosis factor α (TNF-α), inhibit osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), and several microRNAs are implicated in osteoporosis development. This study aimed to explore the correlation between TNF-α treatment and miR-27a-3p expression in BMSC osteogenesis and further understand their roles in osteoporosis. An osteoporosis animal model was established using ovariectomized (OVX) mice. Compared with Sham mice, the OVX mice had a significantly elevated level of serum TNF-α and decreased level of bone miR-27a-3p, and in vitro TNF-α treatment inhibited miR-27a-3p expression in BMSCs. In addition, miR-27a-3p promoted osteogenic differentiation of mouse BMSCs in vitro, as evidenced by alkaline phosphatase staining and Alizarin Red-S staining, as well as enhanced expression of the osteogenic markers Runx2 and Osterix. Subsequent bioinformatics analysis combined with experimental validation identified secreted frizzled-related protein 1 (Sfrp1) as a downstream target of miR-27a-3p. Sfrp1 overexpression significantly inhibited the osteogenic differentiation of BMSCs in vitro and additional TNF-α treatment augmented this inhibition. Moreover, Sfrp1 overexpression abrogated the promotive effect of miR-27a-3p on the osteogenic differentiation of BMSCs. Furthermore, the miR-27a-3p-Sfrp1 axis was found to exert its regulatory function in BMSC osteogenic differentiation via regulating Wnt3a-ß-catenin signalling. In summary, this study revealed that TNF-α regulated a novel miR-27a-3p-Sfrp1 axis in osteogenic differentiation of BMSCs. The data provide new insights into the development of novel therapeutic strategies for osteoporosis.

Understanding the electrochemical properties of Mg-doped Li2MnO3: first-principles calculations.

Non-transition metal doping, especially for Mg, has been gradually employed to optimize the electrochemical performance of Li-rich cathode material Li2MnO3. However, the effects of Mg doping on the electrochemical behavior of Li2MnO3 have not been studied extensively. In this work, we investigate the effect of Mg doping at both the 2b (in the Li/Mn mixed layer) and 4h (in the Li layer) Li sites on the electrochemical properties of Li2MnO3 through first-principles calculations and ab initio molecular dynamics simulations. The local lattice structure, electronic density of states, Bader charge, delithiation voltage, lattice oxygen stability and Li diffusion kinetics are examined. Electronic structure analysis shows that Mg can activate the electrochemical activity of surrounding Mn by charge transfer, making Mn participate in charge compensation at the initial delithiation stage. Mg doping can also cause an increase in the average oxygen vacancy formation energy and hence depress the oxygen release during the delithiation process. Molecular dynamics simulations show that the diffusion kinetics of Li ions in Mg2b-Li2MnO3 is enhanced with respect to the undoped one, whereas Mg doped at the 4h site cannot improve the diffusion kinetics of Li ions. Further studies found that Mg doped at the 2b site results in a decrease in the energy barrier for the intra-layer diffusion and an increase in the energy barrier for the inter-layer diffusion of the nearby Li vacancies.

Oxidation of tetracycline hydrochloride with a photoenhanced MIL-101(Fe)/g-C3N4/PMS system: Synergetic effects and radical/nonradical pathways.

MIL-101(Fe)-based catalysts have been widely used for degradation of organic pollutants based on peroxymonosulfate (PMS) activation. Hence, a facile calcination and hydrothermal method was used in this study to prepare a MIL-101(Fe)/g-C3N4 composite catalyst with high activity and high stability for PMS activation to degrade tetracycline hydrochloride (TC) under visible-light irradiation. We clearly elucidated the mechanism involved in the MIL-101(Fe)/g-C3N4 photo Fenton-catalyzed PMS activation process by separating the PMS activation and pollutant oxidation processes. The synergetic effects of MIL-101(Fe) and g-C3N4 involved MIL-101(Fe) acting as an electron shuttle mediating electron transfer from the organic substrate to PMS, accompanied by redox cycling of the surface Fe(II)/Fe(III). Multiple experimental results indicated that PMS was bound to the surface of MIL-101(Fe)/g-C3N4 during visible irradiation and generation of sulfate radicals (SO4•-), hydroxyl radicals (•OH) and superoxide anion free radicals (•O2-) for the radical pathway and singlet oxygen (1O2) and holes (h+) for the nonradical pathway. The major degradation pathways for TC can be described as demethylation, deamination, deamidation and carbonylation. This work provides valuable information and advances the fundamental understanding needed for design and syntheses of metal-free conjugated polymers modified by metal-organic frameworks for heterogeneous photo-Fenton reactions.

Efficient Fe3C-CF Cathode Catalyst Based on the Formation/Decomposition of Li2-xO2 for Li-O2 Batteries.

Lithium-oxygen batteries have attracted considerable attention in the past several years due to their ultra-high theoretical energy density. However, there are still many serious issues that must be addressed before considering practical applications, including the sluggish oxygen redox kinetics, the limited capacity far from the theoretical value, and the poor cycle stability. This study proposes a surface modification strategy that can enhance the catalytic activity by loading Fe3C particles on carbon fibers, and the microstructure of Fe3C particle-modified carbon fibers is studied by multiple materials characterization methods. Experiments and density functional theory (DFT) calculations show that the discharge products on the Fe3C carbon fiber (Fe3C-CF) cathode are mainly Li2-xO2. Fe3C-CF exhibits high catalytic ability based on its promotion of the formation/decomposition processes of Li2-xO2. Consequently, the well-designed electrode catalyst exhibits a large specific capacity of 17,653.1 mAh g-1 and an excellent cyclability of 263 cycles at a current of 200 mA g-1.

Enriched Surface Oxygen Vacancies of Fe2(MoO4)3 Catalysts for a PDS-Activated photoFenton System.

The environmentally benign Fe2(MoO4)3 plays a crucial role in the transformation of organic contaminants, either through catalytically decomposing oxidants or through directly oxidizing the target pollutants. Because of their dual roles and the complex surface chemical reactions, the mechanism involved in Fe2(MoO4)3-catalyzed PDS activation processes remains obscure. In this study, Fe2(MoO4)3 was prepared via the hydrothermal and calcine method, and photoFenton degradation of methyl orange (MO) was used to evaluate the catalytic performance of Fe2(MoO4)3. Fe2(MoO4)3 catalysts with abundant surface oxygen vacancies were used to construct a synergistic system involving a photocatalyst and PDS activation. The oxygen vacancies and Fe2+/Fe3+ shuttle played key roles in the novel pathways for generation of •O2-, h+, and 1O2 in the UV-Vis + PDS + FMO-6 photoFenton system. This study advances the fundamental understanding of the underlying mechanism involved in the transition metal oxide-catalyzed PDS activation processes.

Efficient Degradation of Congo Red in Water by UV-Vis Driven CoMoO4/PDS Photo-Fenton System.

In order to improve the catalytic activity of cobalt molybdate (CoMoO4), a PDS-activated and UV-vis assisted system was constructed. CoMoO4 was prepared by coprecipitation and calcination, and characterized by XRD, FTIR, Raman, SEM, TEM, XPS, TGA Zeta potential, BET, and UV-Vis DRS. The results showed that the morphology of the CoMoO4 nanolumps consisted of stacked nanosheets. XRD indicated the monoclinic structures with C2/m (C32h, #12) space group, which belong to α-CoMoO4, and both Co2+ and Mo6+ ions occupy distorted octahedral sites. The pH of the isoelectric point (pHIEP) of CMO-8 at pH = 4.88 and the band gap of CoMoO4 was 1.92 eV. The catalytic activity of CoMoO4 was evaluated by photo-Fenton degradation of Congo red (CR). The catalytic performance was affected by calcination temperature, catalyst dosage, PDS dosage, and pH. Under the best conditions (0.8 g/L CMO-8, PDS 1 mL), the degradation efficiency of CR was 96.972%. The excellent catalytic activity of CoMoO4 was attributed to the synergistic effect of photo catalysis and CoMoO4-activated PDS degradation. The capture experiments and the ESR showed that superoxide radical (·O2-), singlet oxygen (1O2), hole (h+), sulfate (SO4-·), and hydroxyl (·OH-) were the main free radicals leading to the degradation of CR. The results can provide valuable information and support for the design and application of high-efficiency transition metal oxide catalysts.

Undercorrection: the undesired effect of compression on the osteotomy gap of the medial opening wedge high tibial osteotomy and its clinical significance.

INTRODUCTION: Undercorrection is a common problem in opening wedge high tibial osteotomy (OWHTO). We investigated the compression effect of cortex screw on the osteotomy gap and its clinical significance. MATERIALS AND METHODS: A standard OWHTO using the TomoFix plate was conducted on 20 bone models in two groups to get a 10-mm medial osteotomy gap. A cortex screw was used temporarily in a neutral (at the center) and an eccentric position (near the inclined plane) of the dynamic hole in group 1 and group 2, respectively. The mean of undercorrection observed in the two groups was compared using an independent t test. Also, the effect of compression on the gap between the plate and medial tibial cortex, and the osteotomy gap was evaluated using a Sine rule. Besides, the mean undercorrection observed was assessed for clinical significance based on the effect on the weight-bearing axis (WBA) using a Cosine Rule. RESULTS: The mean undercorrection was 1.3 ± 0.6 mm and 2.6 ± 0.6 mm in group 1 and group 2, respectively. A significantly greater undercorrection was observed in group 2 (p < 0.001). The correction loss in group 2 has resulted from combinations of the sliding effect of the dynamic hole and oblique compression effect over the gap between the plate and medial tibial cortex whereas in group 1 it has only resulted from the oblique compression effect. The observed undercorrection in group 2 has resulted in clinically significant WBA shift (10%) over the width of the tibial plateau. CONCLUSIONS: In OWHTO, compression is important for the stability and healing of osteotomy, but it can also cause loss of correction. In patients requiring large correction, the surgeon should control the amount of compression required and consider making extra osteotomy gap to avoid undercorrection. Furthermore, the placement of cortex screws in neutral is essential to lower the risk of undercorrection.

Abscisic acid-dependent PMT1 expression regulates salt tolerance by alleviating abscisic acid-mediated reactive oxygen species production in Arabidopsis.

Phosphocholine (PCho) is an intermediate metabolite of nonplastid plant membranes that is essential for salt tolerance. However, how PCho metabolism modulates response to salt stress remains unknown. Here, we characterize the role of phosphoethanolamine N-methyltransferase 1 (PMT1) in salt stress tolerance in Arabidopsis thaliana using a T-DNA insertional mutant, gene-editing alleles, and complemented lines. The pmt1 mutants showed a severe inhibition of root elongation when exposed to salt stress, but exogenous ChoCl or lecithin rescued this defect. pmt1 also displayed altered glycerolipid metabolism under salt stress, suggesting that glycerolipids contribute to salt tolerance. Moreover, pmt1 mutants exhibited altered reactive oxygen species (ROS) accumulation and distribution, reduced cell division activity, and disturbed auxin distribution in the primary root compared with wild-type seedlings. We show that PMT1 expression is induced by salt stress and relies on the abscisic acid (ABA) signaling pathway, as this induction was abolished in the aba2-1 and pyl112458 mutants. However, ABA aggravated the salt sensitivity of the pmt1 mutants by perturbing ROS distribution in the root tip. Taken together, we propose that PMT1 is an important phosphoethanolamine N-methyltransferase participating in root development of primary root elongation under salt stress conditions by balancing ROS production and distribution through ABA signaling.

Flexible n-type thermoelectric materials by organic intercalation of layered transition metal dichalcogenide TiS2.

Organic semiconductors are attracting increasing interest as flexible thermoelectric materials owing to material abundance, easy processing and low thermal conductivity. Although progress in p-type polymers and composites has been reported, their n-type counterpart has fallen behind owing to difficulties in n-type doping of organic semiconductors. Here, we present an approach to synthesize n-type flexible thermoelectric materials through a facile electrochemical intercalation method, fabricating a hybrid superlattice of alternating inorganic TiS2 monolayers and organic cations. Electrons were externally injected into the inorganic layers and then stabilized by organic cations, providing n-type carriers for current and energy transport. An electrical conductivity of 790 S cm(-1) and a power factor of 0.45 mW m(-1) K(-2) were obtained for a hybrid superlattice of TiS2/[(hexylammonium)x(H2O)y(DMSO)z], with an in-plane lattice thermal conductivity of 0.12 ± 0.03 W m(-1) K(-1), which is two orders of magnitude smaller than the thermal conductivities of the single-layer and bulk TiS2. High power factor and low thermal conductivity contributed to a thermoelectric figure of merit, ZT, of 0.28 at 373 K, which might find application in wearable electronics.

CaWRKY40, a WRKY protein of pepper, plays an important role in the regulation of tolerance to heat stress and resistance to Ralstonia solanacearum infection.

WRKY proteins form a large family of plant transcription factors implicated in the modulation of numerous biological processes, such as growth, development and responses to various environmental stresses. However, the roles of the majority WRKY family members, especially in non-model plants, remain poorly understood. We identified CaWRKY40 from pepper. Transient expression in onion epidermal cells showed that CaWRKY40 can be targeted to nuclei and activates expression of a W-box-containing reporter gene. CaWRKY40 transcripts are induced in pepper by Ralstonia solanacearum and heat shock. To assess roles of CaWRKY40 in plant stress responses we performed gain- and loss-of-function experiments. Overexpression of CaWRKY40 enhanced resistance to R. solanacearum and tolerance to heat shock in tobacco. In contrast, silencing of CaWRKY40 enhanced susceptibility to R. solanacearum and impaired thermotolerance in pepper. Consistent with its role in multiple stress responses, we found CaWRKY40 transcripts to be induced by signalling mechanisms mediated by the stress hormones salicylic acid (SA), jasmonic acid (JA) and ethylene (ET). Overexpression of CaWRKY40 in tobacco modified the expression of hypersensitive response (HR)-associated and pathogenesis-related genes. Collectively, our results suggest that CaWRKY40 orthologs are regulated by SA, JA and ET signalling and coordinate responses to R. solanacearum attacks and heat stress in pepper and tobacco.

2-Methyl-1,1-diphenyl-2-[(4S)-4-phenyl-4,5-di-hydro-1,3-oxazol-2-yl]propan-1-ol.

In the title compound, C25H25NO2, the phenyl ring on the 1,3-oxazole ring is disordered over two positions with occupancies of 0.600 (4) and 0.400 (4). The inter-planar angle between these two disordered rings is 77.8 (2)°. There is an intra-molecular O-H⋯N hydrogen bond of moderate strength. In the crystal, C-H⋯π inter-actions interconnect neighbouring molecules. The absolute structure has been derived from the known absolute structure of the reagents.

Highly Stable Garnet Fe2 Mo3 O12 Cathode Boosts the Lithium-Air Battery Performance Featuring a Polyhedral Framework and Cationic Vacancy Concentrated Surface.

Lithium-air batteries (LABs), owing to their ultrahigh theoretical energy density, are recognized as one of the next-generation energy storage techniques. However, it remains a tricky problem to find highly active cathode catalyst operating within ambient air. In this contribution, a highly active Fe2 Mo3 O12 (FeMoO) garnet cathode catalyst for LABs is reported. The experimental and theoretical analysis demonstrate that the highly stable polyhedral framework, composed of FeO octahedrons and MO tetrahedrons, provides a highly effective air catalytic activity and long-term stability, and meanwhile keeps good structural stability. The FeMoO electrode delivers a cycle life of over 1800 h by applying a simple half-sealed condition in ambient air. It is found that surface-rich Fe vacancy can act as an O2 pump to accelerate the catalytic reaction. Furthermore, the FeMoO catalyst exhibits a superior catalytic capability for the decomposition of Li2 CO3 . H2 O in the air can be regarded as the main contribution to the anode corrosion and the deterioration of LAB cells could be attributed to the formation of LiOH·H2 O at the end of cycling. The present work provides in-depth insights to understand the catalytic mechanism in air and constitutes a conceptual breakthrough in catalyst design for efficient cell structure in practical LABs.

Piezo-photocatalytic properties of BaTiO3/CeO2 nanoparticles with heterogeneous structure synthesized by a gel-assisted hydrothermal method.

BaTiO3/CeO2 nanoparticles with heterogeneous structure were successfully synthesized via a gel-assisted hydrothermal method. The molar ratio of Ti/Ce was set as 1 : 0, 0.925 : 0.075, 0.9 : 0.1; 0.875 : 0.125, and 0.85 : 0.15 in the dried gels. Affected by the values of Ti/Ce, the particle sizes of hydrothermal products decreased obviously, and the surface of nanoparticles became rough and even had small protrusions. XRD, SEM, HRTEM, XPS, DRS, ESR, and PFM were used to characterize the nanoparticle textures. We speculated that the main body and surface of nanoparticles were BaTiO3 and CeO2 protrusions, respectively. The catalytic performance of BaTiO3/CeO2 nanoparticles was characterized by their abilities to degrade RhB in water under different external conditions (light irradiation, ultrasonic oscillation, or both). In all test groups, BaTiO3/CeO2 nanoparticles with a Ti/Ce molar ratio of 0.875 : 0.125 in the initial dried gel exhibited the strongest catalytic ability when light irradiation and ultrasonication were applied simultaneously owing to the appropriate amount of Ce3+ and oxygen vacancies.

Interfacial Engineering of MoS2/V2O3@C-rGO Composites with Pseudocapacitance-Enhanced Li/Na-Ion Storage Kinetics.

Molybdenum sulfide has been widely investigated as a prospective anode material for Li+/Na+ storage because of its unique layered structure and high theoretical capacity. However, the enormous volume variation and poor conductivity limit the development of molybdenum sulfide. The rational design of a heterogeneous interface is of great importance to improve the structure stability and electrical conductivity of electrode materials. Herein, a high-temperature mixing method is implemented in the hydrothermal process to synthesize the hybrid structure of MoS2/V2O3@carbon-graphene (MoS2/V2O3@C-rGO). The MoS2/V2O3@C-rGO composites exhibit superior Li+/Na+ storage performance due to the construction of the interface between the MoS2 and V2O3 components and the introduction of carbon materials, delivering a prominent reversible capacity of 564 mAh g-1 at 1 A g-1 after 600 cycles for lithium-ion batteries and 376.3 mAh g-1 at 1 A g-1 after 450 cycles for sodium-ion batteries. Theoretical calculations confirm that the construction of the interface between the MoS2 and V2O3 components can accelerate the reaction kinetics and enhance the charge-ionic transport of molybdenum sulfide. The results illustrate that interfacial engineering may be an effective guide to obtain high-performance electrode materials for Li+/Na+ storage.

Identification, in silico selection, and mechanism study of novel antioxidant peptides derived from the rice bran protein hydrolysates.

The work aimed to assess the antioxidant ability and obtain a new antioxidant peptide from rice bran protein. Rice bran protein was hydrolyzed by Alcalase, Neutral, Pepsin, Chymotrypsin, and Trypsin, separately. Trypsin hydrolysate (T-RBPH) showed high Fe2+ chelating activity (IC50, 2.271 ± 0.007 mg/mL), DPPH and hydroxyl radical scavenging ability (IC50, 0.191 ± 0.006 and 1.038 ± 0.034 mg/mL). Moreover, T-RBPH could alleviate the H2O2-induced oxidative damage in Caco-2. The T-RBPH was purified and identified by UF, GF, FPLC, and LC-MS/MS. Finally, 9-amino acid peptide-AFDEGPWPK with low molecular weight (1045.48 Da), high antioxidant activity, good safety, and solubility was screened by in silico method and chemical oxidation determination, and its interaction with Keap1 was also demonstrated. The ORAC and DPPH radical scavenging ability of AFDEGPWPK were 44.16 ± 0.79 and 28.38 ± 0.14 µmol TE/mM. Moreover, the Molecular docking and Western blot (WB) results showed that AFDEGPWPK could enter the binding pocket in the Kelch domain and activate Keap1/Nrf2/HO-1 pathway.

Fabrication of dielectric nanocubes in ordered structure by capillary force assisted self-assembly method and their piezoresponse properties.

Ordered structures of barium titanate (BT) nanocubes, strontium titanate (ST) nanocubes and BT/ST nanocubes mixture were directly fabricated on Si and Pt-coated Si substrates using a capillary force assisted assembly method. The morphology of self-assembled structures was observed using field emission scanning electron microscopy (FE-SEM) and scanning probe microscopy (SPM). It was revealed that nanocubes were arranged with various degrees of ordering to develop multilayer and monolayer regions at the surface of substrates. The elemental mapping of the structure consisting of the nanocubes mixture was also investigated by transmission electron microscopy (TEM) with an energy dispersive X-ray spectroscopy (EDX). It was revealed that BT and ST nanocubes coexisted homogeneously in the structure and had possibility to be arranged in order to each other. The piezoresponse properties obtained by scanning probe microscopy (SPM) indicated that the hetero-interface between BT and ST nanocubes would introduce anomaly in piezoelectric properties.

Sappanone A Alleviated IL-1ß-Induced Inflammation in OA Chondrocytes through Modulating the NF-κB and Nrf2/HO-1 Pathways.

Objective: This study was to examine the anti-inflammatory effect of sappanone A on interleukin- (IL-) 1ß-stimulated osteoarthritis (OA) chondrocytes. Methods: Chondrocytes were pretreated with sappanone A for 2 h before subsequent IL-1ß stimulation. The mRNA expression levels of iNOs, COX-2, aggrecan, and collagen-II were measured with qRT-PCR. The levels of TNF-α, IL-6, IL-8, MMP-3, and MMP-13 were determined by ELISA. The protein levels of iNOs, COX-2, ADAMTS-4, ADAMTS-5, aggrecan, collagen-II, p-p65, p65, IκBα, Nrf2, and HO-1 were assessed by Western blot. Results: Sappanone A inhibited the IL-1ß-stimulated production of NO, PGE2, iNOS, COX-2, TNF-α, IL-6, and IL-8 in OA chondrocytes. In addition, sappanone A suppressed the expression of MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5 in IL-1ß-stimulated OA chondrocytes. The degradation of ECM components was reversed by sappanone A. Sappanone A prevented NF-κB activation while enhanced Nrf2/HO-1 activation in IL-1ß-treated chondrocytes. Conclusion: Sappanone A may be a potent therapeutic agent for OA.

Identification and in silico analysis of novel antioxidant peptides in broken rice protein hydrolysate and its cytoprotective effect against H2O2-induced 2BS cell model.

Broken rice is an important by-product during milling process of rice, which is rich in protein. To increase the value of by-products and search for effective antioxidants, the antioxidant peptides from broken rice protein hydrolysate were separated and identified by ultrafiltration, gel filtration chromatography, fast protein liquid chromatography, and LC-MS/MS in this study. These identified peptides were further screened using a combined in silico and in vitro method and their antioxidant mechanism was explored by Western blot and molecular docking analysis. Ninety-eight peptides were obtained after antioxidant activity-oriented isolation and four novel peptides, SGDWSDIGGR, DFGSEILPR, GEPFPSDPKKQLQ, and GEKGGIPIGIGK, with excellent solubility, safety, and antioxidant activity were synthesized. Among these, SGDWSDIGGR showed good antioxidant activities in the extracellular assay (41.57 µmol TE/g and 29.41 % in ORAC and DPPH assay, respectively.), and it possessed a protective effect against H2O2-injured oxidative stress in 2BS cells in a dose-dependent manner. Furthermore, Western blot and molecular docking results showed that SGDWSDIGGR achieves antioxidant ability by occupying the Nrf2-binding site, activating the Keap1-Nrf2 signaling pathway, and upregulating the expression of antioxidant enzymes. This study extends the rice industry chain and provides insights into the selection and mechanisms research of antioxidant peptides.