BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were ...BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were randomly divided into three groups; control, low-dose alcohol, and high-dose alcohol. Each al- cohol group ( n = 12) was intravenously infused with etha- nol at a dose of 0.3 or 0.7 g/kg body weight respectively. The control group (n =11) was intravenously infused with normal saline at a dose of 0.5 g/kg body weight. Blood was collected for detection of hepatic enzymes and index of oxidation/antioxidation. RESULTS: The ratio of AST to ALT was 2.44±0.46, 2.57± 0.60 and 3.03 ±0.46 in the three groups, and the difference was significant between the control and high-dose alcohol groups (P^0.05). No significant changes were observed in the levels of serum alanine aminotransferase (ALT), aspar- tate aminotransferase (AST), total protein (Tp), albumin (Alb), alkaline phosphatase (ALP), cholinesterase (ChE), total bilirubin (TB), C-reactive protein (CRP) and amy- lase. The levels of serum nitric oxide (NO) in the 3 groups were 39.2 ±73.25 mol/L, 42.30 ±4.60 mol/L and 47.86± 4.66 mol/L, and significant difference was seen between the control group and the high-dose alcohol group (P < 0.01). No significant difference was found in the levels of serum superoxide dismutase (SOD), glutathione (GSH), malondiethylaldehyde (MDA), and CRP in the 3 groups. CONCLUSION: The ratio of AST to ALT appears to be a useful index for acute alcohol intoxication. NO is involved in the mechanism of acute alcohol intoxication.展开更多
Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-infla...Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-inflammatory,microbiota regulating,and memory-improving potentials in previous in vitro and AlCl3-induced zebrafish studies.However,its effects of memory-improving and gutbrain axis regulating on Aβ-induced mammalian AD models have not been explored.In this study,intragastric administrated BTL-Ⅰ ameliorated cognitive deficits related to recognition and spatial memory impaired by Aβ_(1-42)intracerebroventricular injection in mice.BTL-Ⅰ maintained gut microbiota balance by increasing the abundance of Blautia,Muribaculaceae,Bacteroides,Akkermansia,etc.,and decreasing CAG-352,Clostridia UCG-014,different Lachnospiraceae groups,etc.,and Firmicutes/Bacteroidota ratio and elevated the levels of short-chain fatty acids.Additionally,it alleviated intestinal oxidative stress,inflammatory responses,and pathological damage.Furthermore,BTL-I reversed Aβ_(1-42)-induced activation of microglia and astrocytes in the hippocampus and inhibited the elevated oxidative stress and proinflammatory cytokines in both plasma and brain.The correlation analysis between the regulated taxa and biomarkers supports the role of gut microbiota in adjusting inflammation,oxidative stress,and memory.In conclusion,BTL-I may serve as a valuable drug lead for treating Alzheimer’s disease by systematically inhibiting microbiota imbalance,inflammation,and oxidative stress along the gut-brain axis.展开更多
Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0...Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury.展开更多
The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that...The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that TiBw reinforcement accelerated the occurrence of Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium in the starting oxidation stage,and the Ti_(6O)/Ti_(3O) transformed into TiO_(2) with the progression of oxidation.Meanwhile,TiBw reinforcement promoted the formation of(101)crystal planes to be beneficial to the growth of TiO_(2) twins.The cross-sectional characterization showed that the oxide layer of Ti55 alloy and TiBw/Ti55 composites from outside to inside was TiO_(2)+Al_(2)O_(3),TiO_(2),Ti-Sn compounds,Ti_(6O)/Ti_(3O) in sequence,which was confirmed by calculating the standard Gibbs free energy of the oxide nucleation.The TiBw reinforcement accelerated the occurrence of suboxides Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium,and promoted the formation of(101)crystal planes which were beneficial to the growth of TiO_(2) twins.The optimal addition of TiBw induced the TiO_(2) twins,promoted the random orientation of oxides and refined the oxide size of the TiBw/Ti55 composites with 3.5%volume fractions of TiBw,resulting in the best resistance against oxidation.展开更多
Consumers are increasingly demanding natural colorants that are safe and offer health benefits.In addition to their ornamental characteristics,Kanzan cherry(KC)blossoms present a promising source of red-hued natural c...Consumers are increasingly demanding natural colorants that are safe and offer health benefits.In addition to their ornamental characteristics,Kanzan cherry(KC)blossoms present a promising source of red-hued natural colorants and functional bioactive substances.This research utilized distilled water to extract KC petals(KCP)and their ground powders(KCPP)under varying temperatures(30℃–90℃)and times(30–180 min).The total monomeric anthocyanins(TMAC)and total phenolics(TPC)in the extracts were evaluated via the pH differential and Folin–Ciocalteu methods.Antioxidant capacities were assessed by DPPH free radical scavenging ability and reducing power.Results indicated that the optimal extraction of TMAC and TPC from KCP occurred at 90℃ for 30 min,and the resulting extracts exhibited the highest antioxidant activities among all tested temperatures and durations.Compared to different particle sizes,the finest KCPP generally produced extracts with the highest TMAC,TPC,and antioxidant activity,due to enhanced mass and heat transfer.When compared with the acidified alcohol method,hot water extraction resulted in 68.23%and 71.41%TMAC yields for petals and powders,respectively,while TPC levels were similar or higher.TMAC or TPC showed a significantly positive correlation(p<0.01)with the antioxidant activities.These findings demonstrate that hot water extraction is a viable and environmentally friendly alternative for phytochemical recovery from KC.Additionally,elevated extraction temperature and pH accelerated anthocyanin degradation and shortened its half-life,while higher pH also lowered the activation energy,enthalpy,entropy,and Gibbs free energy.Thus,red–orange KC extracts with rich bioactivity may serve as promising ingredients for functional foods having acidic pH levels.展开更多
NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxi...NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxidation property and corrosion resistance of the NiTi alloy.In order to overcome the above problems,we constructed Zn/polydopamine(PDA)/Chitosan-Catechol(CS-C)composite coating on the surface of NiTi alloy in this paper.The surface morphology and wettability of the coating were characterized by scanning electron microscopy(SEM)and optical contact angle measuring instrument,respectively.The results showed that the Zn/CS-C coating was successfully prepared,and exhibited good hydrophilic property,especially the sample Zn/PDA/CS-C-24 h.In addition,the corrosion resistance,antioxidation property and biological properties of the coating were systematically analyzed.The results indicated that the Zn/PDA/CS-C composite coating exhibited good corrosion resistance and antibacterial property,antioxidant property and osteogenic activity,especially sample Zn/PDA/CS-C-24 h.The sample Zn/PDA/CS-C-24 h could effectively protect osteoblasts from reactive oxygen species(ROS)damage and promote cell proliferation and osteoblast differentiation.This study provides a feasible and effective strategy for the surface modification of orthopedic implant.展开更多
[Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a h...[Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a high-dose group,n=10; the protein content, the activities of the superoxide dismutase(SOD) and the glutathione peroxidase(GSH-PX), the content of the maleic dialdehyde(MDA) in serum and liver tissue of the rats from different groups were determined. [Result]The polyphenols of pomegranate peel could increase protein content, activities of superoxide dismutase(SOD) and glutathione peroxidase(GSH-PX) in serum and liver tissue, and decrease the maleic dialdehyde(MDA) content simultaneously. [Conclusion] Polyphenols of pomegranate peel have strong antioxidant activity in vivo.展开更多
[Objective] The aim was to compare contents of free and bound polyphenol and antioxidation of balsam pear in different varieties. [Method] Fourteen varieties of balsam pear were chosen to analyze total contents of fre...[Objective] The aim was to compare contents of free and bound polyphenol and antioxidation of balsam pear in different varieties. [Method] Fourteen varieties of balsam pear were chosen to analyze total contents of free or bound phenol and components of free phenol. FRAP (Freeic reducing/antioxidant power), DPPH (1,1diphenyl-2-picrylhydrazy), and ABTS +· (2, 2’-azinobis-3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) were used to measure antioxidation and analyze relationship between polyphenol content and antioxidation. [Result] Among the fourteen varieties of balsam pear, free, bound and total phenols were 157.58 -382.92, 6.46 -54 and 175.27 -413.79 mg GAE/100 g DW; coefficients of variance were 23.50% , 61.04% and 21.58%, respectively; free phenol accounted for 91.34% of total phenol and bound phenol accounted for 8.66% ; contents of total flavone for the fourteen varieties were from 8.97 to 18.22 mg CE/100 g DW and the coefficient was at 22.80%; vanillic aldehyde acid, epicatechin and rutin differed in contents among different varieties, which changed in 1.83-9.29, 35.17-114.52 and 0.91-4.53 mg/100 g DW and the coefficients were 43.85%, 26.97% and 33.09%; FRAP antioxidation was at 272.16 -713.32 mg TE/100 g DW and coefficient at 27.67% ; IC 50 of DPPH and ABTS +· clearance were 11.43-34.14 and 21.57-119.71 mg GAE/100 g DW and coefficients were at 35.10% and 63.75% , accordingly; content of total phenol was of extremely positive correlation with FRAP (P0.01) and of extremely negative correlation with IC 50 of DPPH and ABTS + · clearance (P0.01). [Conclusion] Contents of phenolic compounds and antioxidation are of significant genotype differences; and phenolic substance and antioxidation are mainly in free form and phenolic substance is the major basis for antioxidation.展开更多
To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre...To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.展开更多
Carbon fiber-reinforced carbon aerogel(C/CA)composites are one of the most promising candidates for applications requiring both thermal insulation and load bearing capabilities.The preparation of anti-oxidation coatin...Carbon fiber-reinforced carbon aerogel(C/CA)composites are one of the most promising candidates for applications requiring both thermal insulation and load bearing capabilities.The preparation of anti-oxidation coatings on C/CA to address its susceptibility to oxidation is a feasible approach to promote its application in oxidative environments.However,the currently reported coatings on C/CA mainly focus on improving the ablation performance and coating preparation process typically necessitating high-temperature heat treatment.This procedure can increase its thermal conductivity and reduce its thermal insulation ability.In this study,a series of ceramic-resin coatings were fabricated on C/CA through a simple slurry brushing-drying approach at room temperature.The effects of phenolic resin content on the coating structure,residual stress,thermal shock,and oxidation behaviors were investigated.Due to the adhesive properties and curing-induced shrinkage,the PR-7.5 coating(containing 7.5%(in mass)phenolic resin in the slurry)exhibits bonding strength close to fracture strength of the substrate and residual compressive stress of 0.853 GPa,which is beneficial for resisting thermal shock cracking.However,excessive resin content(PR-10.0 containing 10.0%(in mass)phenolic resin in the slurry)induces tensile stress due to uneven curing shrinkage,thereby leading to thermal shock cracking.Meanwhile,oxidation tests reveal significantly reduced weight losses for PR-7.5(17.46%at 800℃/100 min,8.15%at 1000℃/120 min,3.15%at 1200℃/120 min)versus uncoated C/CA’s 44.60%loss at 800℃/20 min.This work provides a brand-new and simple approach to improving the anti-oxidation performance of C/CA and expands its application in mild oxidative environments.展开更多
The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical pr...The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical properties,can significantly enhance the oxidation resistance of Mg alloys.Based on our previous study,we conclude that REs such as Gd,Y,and Ce enhance the oxidation resistance of Mg-RE alloys.This article comprehensively reviews recent research progress on high-temperature oxidation behavior and the potential mechanism in Mg-RE alloys.Based on the thermodynamic and kinetic analyses,the evolution of the complex oxide system formed during the high-temperature oxidation of Mg-RE alloys is first summarized.The diffusion behavior and concentration control mechanisms of REs during the oxidation process and how these mechanisms affect the sustained growth of the oxide film and antioxidant properties were elucidated.Moreover,the different structures of the oxide films were classified,and their properties were discussed.Finally,this paper introduces the applications of commonly used REs in Mg alloys and frontier research on their oxidation mechanisms.Based on the above review,we propose that future research perspectives can be explored in terms of expanding the experimental temperature range for oxidation tests,optimizing the chemical composition by adding trace REs to study their synergistic mechanism,revealing the underlying oxidation mechanism through advanced in situ microscopic characterization methods,and investigating the mechanical properties of oxide films using diverse approaches.展开更多
Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materi...Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected.展开更多
[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the r...[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the raw material,the effects of ethanol concentration,ultrasonic temperature,time,and solid-to-liquid ratio on the total flavonoid yield were investigated through single-factor and orthogonal experiments.[Results]All factors had a significant effect on the yield.The optimized conditions were determined as follows:ethanol concentration 75%,ultrasonic temperature 60℃,ultrasonic time 30 min,and solid-to-liquid ratio 1:50(g/ml).Under these conditions,the total flavonoid yield reached 3.08%.Evaluation of antioxidant activity revealed that the extract exhibited superior scavenging rates against both DPPH and hydroxyl radicals compared with the standard reference compound BHT.[Conclusions]This study holds significant importance for elucidating the pharmacological mechanisms of flavonoids in H.undatus and for expanding their application in medicine and health products.展开更多
The antioxidant activity of selenium-containing soybean peptides(SePPs)has been previously demonstrated,despite their limited absorption in the small intestine.This study investigates the antioxidant mechanism of a se...The antioxidant activity of selenium-containing soybean peptides(SePPs)has been previously demonstrated,despite their limited absorption in the small intestine.This study investigates the antioxidant mechanism of a selenium-containing tetrapeptide,Ser-Phe-Gln-SeM(SFQSeM),identified from SePPs,with particular emphasis on its interaction with the intestinal microbiota and its role in modulating host antioxidant defenses.The effects of SFQSeM were evaluated in a D-galactose-induced oxidative stress model and an antibiotictreated mouse model.SFQSeM supplementation significantly reduced the oxidative stress in D-galactosetreated mice.It also promoted the growth of beneficial bacteria and increased the levels of acetate,butyrate and lactate in the intestine(P<0.05).In the antibiotic-treated mouse model,depletion of the intestinal microbiota significantly reduced hepatic glutathione peroxidase(GSH-Px)activity(26.6%)and glutathione peroxidase 1(GPx-1)expression(48.77%)compared to normal mice supplemented with SFQSeM(P<0.05).In contrast to Na_(2)SeO_(3)and selenomethionine,SFQSeM effectively restored the diversity of the intestinal microbiota disrupted by antibiotics.Lactobacillus,Lachnospiraceae_NK4A136_group,and Muribaculaceae were identified as predominant bacteria in the SFQSeM group,and were strongly associated with increased hepatic GSH-Px activity and GPx-1 mRNA expression(P<0.05).In conclusion,intestinal microbiota enhances the antioxidant efficacy of SFQSeM by modulating microbial composition,producing active metabolites,and converting SFQSeM into a bioactive form of selenium.展开更多
[Objectives]To evaluate the in vitro antibacterial,antioxidant,andα-glucosidase inhibitory activities of the ethanol total extract and four different polarity fractions(n-butanol,ethyl acetate,petroleum ether,and wat...[Objectives]To evaluate the in vitro antibacterial,antioxidant,andα-glucosidase inhibitory activities of the ethanol total extract and four different polarity fractions(n-butanol,ethyl acetate,petroleum ether,and water)of Pilea peltata Hance,so as to provide a reference for its further development and research.[Methods]The antibacterial activity of P.peltata was evaluated in vitro by determining the minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of its ethanol total extract and four different polarity fractions against seven test bacterial strains using the broth microdilution method.The in vitro antioxidant activity was investigated through DPPH radical,hydroxyl radical,and superoxide anion radical scavenging assays,with vitamin C(Vit C)as the positive control and the half maximal scavenging concentration(IC 50)as the evaluation indicator.The in vitroα-glucosidase inhibitory activity was assessed by measuring the peak area of p-nitrophenol(PNP),the hydrolysis product of 4-nitrophenylα-D-glucopyranoside(PNPG),via high-performance liquid chromatography(HPLC),using the half maximal inhibitory concentration(IC 50)as the evaluation indicator.[Results]Both the ethanol total extract and the four different polarity fractions of P.peltata exhibited significant in vitro anti-Streptococcus pneumoniae activity.The DPPH radical scavenging capacities of the ethanol total extract and the various fractions were all weaker than that of VitC,with the order of efficacy being:n-butanol fraction>ethanol total extract>ethyl acetate fraction>petroleum ether fraction>aqueous fraction.For hydroxyl radical scavenging activity,the efficacy order of P.peltata fractions was:n-butanol extract>ethyl acetate extract>ethanol total extract>petroleum ether extract>aqueous extract.Notably,the n-butanol fraction(IC 50=0.068±0.001)demonstrated stronger activity than VitC(IC 50=0.097±0.001).The activity of the ethyl acetate fraction(IC 50=0.096±0.004)was comparable to that of VitC(IC 50=0.097±0.001).The superoxide anion scavenging capacities of the ethanol total extract and different polarity fractions from P.peltata were all weaker than that of VitC,with the order of efficacy being:n-butanol fraction>ethyl acetate fraction>ethanol total extract>petroleum ether fraction>aqueous fraction.The ethanol total extract and aqueous fraction of Pilea peltata showed no significant in vitroα-glucosidase inhibitory activity.Compared with the acarbose group,the IC 50 values of the ethyl acetate fraction and the n-butanol fraction both showed highly significant differences(P<0.01).[Conclusions]This study provides an experimental basis for the pharmacodynamic study and active component study of P.peltata.展开更多
Objectives:Oxidative stress(OS)plays a pivotal role in chronic and neurodegenerative diseases,which has sparked interest in molecules that modulate redox-regulating enzymes.Melatonin and its metabolites exhibit antiox...Objectives:Oxidative stress(OS)plays a pivotal role in chronic and neurodegenerative diseases,which has sparked interest in molecules that modulate redox-regulating enzymes.Melatonin and its metabolites exhibit antioxidant properties;however,their molecular mechanisms of enzymatic and transcriptional modulation remain unclear.This study aimed to investigate,through an exploratory in silico approach,the interactions of melatonin and related compounds with OS-related enzymes to generate hypotheses about their role in cellular redox control.Methods:A rational selection of antioxidant,pro-oxidant,and transcriptional targets was performed.Ligands were optimized at the DFT level(M05-2X/6-311+G(d,p))and docked to OS related enzymes.Docking results were analyzed using polygenic antioxidant indices(PAOX)and a similarity interaction index(SSI).Molecular dynamics simulations of selected complexes provided additional insight into potential ligand-protein interaction mechanisms.Results:In silico analyses revealed that N1-acetyl-5-methoxykynuramine(AMK),N1-acetyl-N2-formyl-5-methoxykynuramine(AFMK),and 3-hydroxymelatonin(3OH-M)could partially inhibit pro-oxidant enzymes such as neuronal nitric oxide synthase(nNOS),5-lipoxygenase(5-LOX),thioredoxin reductase(TrxR),and nicotinamide adenine dinucleotide phosphate oxidase(NOX5).The N-(2-(2-acetyl-6,7-dihydroxy-1H-indol-3-yl)ethyl)acetamide(IIcD)and N-(2-(6-hydroxy-7-mercapto-5-methoxy-1H-indol)ethyl)acetamide(dM38)derivatives could potentially stabilize superoxide dismutase(SOD1)and catalase(CAT)enzymes,respectively.Finally,AFMK and dM38 showed consistent interactions with transcriptional regulators,particularly peroxisome proliferator-activated receptor alpha(PPARα)and Kelchlike ECH-associated protein 1(KEAP1).Conclusion:These studies about melatonin-related compounds support a multifactorial profile of redox modulation and provide mechanistic hypotheses for future experimental validation.Among these approaches,the interaction-similarity index is introduced as a novel tool to facilitate the identification of promising redox-active candidates.展开更多
Carotenoids are natural pigments that are widely distributed in the flowers,fruits,and seeds of many plant species.These compounds not only endow diverse colors but also exhibit antioxidant,immune-modulatory,anti-agin...Carotenoids are natural pigments that are widely distributed in the flowers,fruits,and seeds of many plant species.These compounds not only endow diverse colors but also exhibit antioxidant,immune-modulatory,anti-aging,and photoprotective properties.Although carotenoid metabolism has been studied extensively in microbial and plant science,the genetic mechanisms underlying carotenoid metabolism in cotton remain underexplored.Here,we isolated gene GbDYA that regulates a dark-yellow anther color by map-based cloning using a BC1F1 population derived from a cross of Gossypium barbadense acc.Hai7124 with dark-yellow anthers and G.hirsutum acc.TM-1 with light-yellow anthers backcrossed with TM-1.GbDYA encodes phytoene synthase,a key rate-limiting enzyme in the carotenoid biosynthesis pathway.A long terminal repeat retrotransposon in the first exon of GhDYA(an ortholog of GbDYA in G.hirsutum acc.TM-1)caused loss of function and led to the light-yellow anther color.GbDYA is predominantly expressed in the early stages of anther development.Transcriptome,RT-qPCR and KEGG enrichment analyses revealed that GbDYA influences the synthesis and accumulation of carotenoids in anthers by modulating expression of key genes in the carotenoid biosynthesis pathway.Integrated transcriptomic and metabolomic analyses indicated that the accumulation of lutein,violaxanthin,antherxanthin,cryptoxanthin,zeaxanthin,andβ-carotene contributed to yellow coloration of anthers.Dual-luciferase and yeast one-hybrid assays confirmed that transcription factor GbMYB105(GB_A11G3511)binds to the promoter of GbDYA and activates its expression.High-temperature stress treatment indicated that carotenoids accumulation in anthers enhances pollen antioxidant activity.This study unravels the role of GbDYA in conferring the anther coloration,and provides the potential utilization by modulating accumulation of carotenoids in anthers to enhance pollen viability in high-temperature tolerance breeding in cotton.展开更多
Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive com...Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive compounds such as flavonoids and alkaloids,which influence multiple biological pathways.This review aims to summarise and critically analyse recent findings on the pharmacological properties of Passiflora incarnata L.,focusing on its neuropsychiatric,antioxidant,antimicrobial,and anticancer activities.A targeted literature search was conducted in PubMed,Scopus,Web of Science,and Google Scholar for peer-reviewed publications between 2000 to 2025.Relevant articles were screened,and a more appropriate article related to the objective of the review was selected.Some classical papers are also cited as per the requirement of the topic.Passiflora incarnata L.showed multifunctional medicinal properties with various applications in neuropsychiatry,oxidative stress management,antimicrobial agent,and as an anticancer agent.The U.S.Food and Drug Administration categorizes passionflower extracts as“generally recognized as safe”.However,most evidence remains preclinical,with methodological variation limiting generalisation.Standardised formulation,robust clinical trials,and in-depth in vivo studies are essential to establish its therapeutic relevance and safety in modern medicine.展开更多
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,...Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.展开更多
Asplactones A-E(1-5),five unique diphenyl ether hybrids,along with two rare spiro-diphenyl ethers,aspviolaceols A(6)and B(7),were isolated and characterized from Aspergillus sp.F1-8A,an endophytic fungus associated wi...Asplactones A-E(1-5),five unique diphenyl ether hybrids,along with two rare spiro-diphenyl ethers,aspviolaceols A(6)and B(7),were isolated and characterized from Aspergillus sp.F1-8A,an endophytic fungus associated with the parotoid glands of Bufo gargarizans Cantor.Compounds 1-5 represent the first examples of diphenyl ether hybrids fused with unusual moieties,including conjugatedγ-butyrolactone and cyclopentenone.Compounds 6 and 7 are the first known natural spiro-diphenyl ethers,with 6 featuring an uncommon 6/6/6/6-membered carbon skeleton,and 7 possessing a distinct 6/6/6/6/6/6-membered diphenyl ether spiro-heterodimer carbon framework.Structural elucidation was performed using a combination of spectroscopic techniques,X-ray crystallography,and quantum-chemical calculations,and plausible biosynthetic pathways were proposed.Biologically,compounds 1,2,4,6,and 7 exhibited antioxidant activity comparable to or surpassing that of vitamin C in 1,1-diphenyl-2-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate)(ABTS),and ferric reducing power assays.They also significantly improved cell viability in H2O2-induced oxidative injury assays using A549 cells.展开更多
文摘BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were randomly divided into three groups; control, low-dose alcohol, and high-dose alcohol. Each al- cohol group ( n = 12) was intravenously infused with etha- nol at a dose of 0.3 or 0.7 g/kg body weight respectively. The control group (n =11) was intravenously infused with normal saline at a dose of 0.5 g/kg body weight. Blood was collected for detection of hepatic enzymes and index of oxidation/antioxidation. RESULTS: The ratio of AST to ALT was 2.44±0.46, 2.57± 0.60 and 3.03 ±0.46 in the three groups, and the difference was significant between the control and high-dose alcohol groups (P^0.05). No significant changes were observed in the levels of serum alanine aminotransferase (ALT), aspar- tate aminotransferase (AST), total protein (Tp), albumin (Alb), alkaline phosphatase (ALP), cholinesterase (ChE), total bilirubin (TB), C-reactive protein (CRP) and amy- lase. The levels of serum nitric oxide (NO) in the 3 groups were 39.2 ±73.25 mol/L, 42.30 ±4.60 mol/L and 47.86± 4.66 mol/L, and significant difference was seen between the control group and the high-dose alcohol group (P < 0.01). No significant difference was found in the levels of serum superoxide dismutase (SOD), glutathione (GSH), malondiethylaldehyde (MDA), and CRP in the 3 groups. CONCLUSION: The ratio of AST to ALT appears to be a useful index for acute alcohol intoxication. NO is involved in the mechanism of acute alcohol intoxication.
基金Supported by the Guangdong Provincial Natural Science Foundation(No.2022A1515010783)the Sustainable Development Program of Shenzhen Science and Technology Major Program(No.KCXFZ20240903093925033)+4 种基金the Guangdong Provincial Special Project in Science and Technology(No.2021A05240)the Special Project in Key Fields of Guangdong Provincial Higher Education Institutions(No.2021ZDZX2064)the Basic Research Project of Shenzhen Science and Technology Innovation Commission(No.JCYJ20220530162014032)the Zhanjiang Marine Youth Talent Innovation Project(No.2022E05010)the Program for Scientific Research Start-up Funds of Guangdong Ocean University(Nos.R18008,060302042201)。
文摘Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-inflammatory,microbiota regulating,and memory-improving potentials in previous in vitro and AlCl3-induced zebrafish studies.However,its effects of memory-improving and gutbrain axis regulating on Aβ-induced mammalian AD models have not been explored.In this study,intragastric administrated BTL-Ⅰ ameliorated cognitive deficits related to recognition and spatial memory impaired by Aβ_(1-42)intracerebroventricular injection in mice.BTL-Ⅰ maintained gut microbiota balance by increasing the abundance of Blautia,Muribaculaceae,Bacteroides,Akkermansia,etc.,and decreasing CAG-352,Clostridia UCG-014,different Lachnospiraceae groups,etc.,and Firmicutes/Bacteroidota ratio and elevated the levels of short-chain fatty acids.Additionally,it alleviated intestinal oxidative stress,inflammatory responses,and pathological damage.Furthermore,BTL-I reversed Aβ_(1-42)-induced activation of microglia and astrocytes in the hippocampus and inhibited the elevated oxidative stress and proinflammatory cytokines in both plasma and brain.The correlation analysis between the regulated taxa and biomarkers supports the role of gut microbiota in adjusting inflammation,oxidative stress,and memory.In conclusion,BTL-I may serve as a valuable drug lead for treating Alzheimer’s disease by systematically inhibiting microbiota imbalance,inflammation,and oxidative stress along the gut-brain axis.
基金supported by the National Natural Science Foundation of China,Nos.82204360(to HM)and 82270411(to GW)National Science and Technology Innovation 2030 Major Program,No.2021ZD0200900(to YL)。
文摘Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury.
基金supported by the Special Project of the Central-Guided Local Science and Technology Development(Grant No.2022ZY2-JCYJ-01-06)the Key Research and Development Program(Grant No.2020-xxx-ZD-179-00-05)Prof.Lujun Huang Group at Harbin Institute of Technology for providing the TiBw/Ti55 composites.
文摘The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that TiBw reinforcement accelerated the occurrence of Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium in the starting oxidation stage,and the Ti_(6O)/Ti_(3O) transformed into TiO_(2) with the progression of oxidation.Meanwhile,TiBw reinforcement promoted the formation of(101)crystal planes to be beneficial to the growth of TiO_(2) twins.The cross-sectional characterization showed that the oxide layer of Ti55 alloy and TiBw/Ti55 composites from outside to inside was TiO_(2)+Al_(2)O_(3),TiO_(2),Ti-Sn compounds,Ti_(6O)/Ti_(3O) in sequence,which was confirmed by calculating the standard Gibbs free energy of the oxide nucleation.The TiBw reinforcement accelerated the occurrence of suboxides Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium,and promoted the formation of(101)crystal planes which were beneficial to the growth of TiO_(2) twins.The optimal addition of TiBw induced the TiO_(2) twins,promoted the random orientation of oxides and refined the oxide size of the TiBw/Ti55 composites with 3.5%volume fractions of TiBw,resulting in the best resistance against oxidation.
基金funded by the Research Fund(Project Number 2025YB12)Innovation and Entrepreneurship Project(2024)of Shanghai Sanda University.
文摘Consumers are increasingly demanding natural colorants that are safe and offer health benefits.In addition to their ornamental characteristics,Kanzan cherry(KC)blossoms present a promising source of red-hued natural colorants and functional bioactive substances.This research utilized distilled water to extract KC petals(KCP)and their ground powders(KCPP)under varying temperatures(30℃–90℃)and times(30–180 min).The total monomeric anthocyanins(TMAC)and total phenolics(TPC)in the extracts were evaluated via the pH differential and Folin–Ciocalteu methods.Antioxidant capacities were assessed by DPPH free radical scavenging ability and reducing power.Results indicated that the optimal extraction of TMAC and TPC from KCP occurred at 90℃ for 30 min,and the resulting extracts exhibited the highest antioxidant activities among all tested temperatures and durations.Compared to different particle sizes,the finest KCPP generally produced extracts with the highest TMAC,TPC,and antioxidant activity,due to enhanced mass and heat transfer.When compared with the acidified alcohol method,hot water extraction resulted in 68.23%and 71.41%TMAC yields for petals and powders,respectively,while TPC levels were similar or higher.TMAC or TPC showed a significantly positive correlation(p<0.01)with the antioxidant activities.These findings demonstrate that hot water extraction is a viable and environmentally friendly alternative for phytochemical recovery from KC.Additionally,elevated extraction temperature and pH accelerated anthocyanin degradation and shortened its half-life,while higher pH also lowered the activation energy,enthalpy,entropy,and Gibbs free energy.Thus,red–orange KC extracts with rich bioactivity may serve as promising ingredients for functional foods having acidic pH levels.
基金jointly supported by the Natural Science Foundation of Shanxi Province(Nos.202203021222127,202403021212109).
文摘NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxidation property and corrosion resistance of the NiTi alloy.In order to overcome the above problems,we constructed Zn/polydopamine(PDA)/Chitosan-Catechol(CS-C)composite coating on the surface of NiTi alloy in this paper.The surface morphology and wettability of the coating were characterized by scanning electron microscopy(SEM)and optical contact angle measuring instrument,respectively.The results showed that the Zn/CS-C coating was successfully prepared,and exhibited good hydrophilic property,especially the sample Zn/PDA/CS-C-24 h.In addition,the corrosion resistance,antioxidation property and biological properties of the coating were systematically analyzed.The results indicated that the Zn/PDA/CS-C composite coating exhibited good corrosion resistance and antibacterial property,antioxidant property and osteogenic activity,especially sample Zn/PDA/CS-C-24 h.The sample Zn/PDA/CS-C-24 h could effectively protect osteoblasts from reactive oxygen species(ROS)damage and promote cell proliferation and osteoblast differentiation.This study provides a feasible and effective strategy for the surface modification of orthopedic implant.
基金Supported by Scientific Research Projects Units of Science and Technology Department of Xinjiang Uygur Autonomous Region for Financial Support(Project No.2013911072)~~
文摘[Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a high-dose group,n=10; the protein content, the activities of the superoxide dismutase(SOD) and the glutathione peroxidase(GSH-PX), the content of the maleic dialdehyde(MDA) in serum and liver tissue of the rats from different groups were determined. [Result]The polyphenols of pomegranate peel could increase protein content, activities of superoxide dismutase(SOD) and glutathione peroxidase(GSH-PX) in serum and liver tissue, and decrease the maleic dialdehyde(MDA) content simultaneously. [Conclusion] Polyphenols of pomegranate peel have strong antioxidant activity in vivo.
基金Supported by Guangdong International Cooperation Program (2010B050600005)Guangdong Comprehensive Strategic Cooperation Project of CAS (2009B091300135)Guangdong Natural Science Foundation (10251064001000006)~~
文摘[Objective] The aim was to compare contents of free and bound polyphenol and antioxidation of balsam pear in different varieties. [Method] Fourteen varieties of balsam pear were chosen to analyze total contents of free or bound phenol and components of free phenol. FRAP (Freeic reducing/antioxidant power), DPPH (1,1diphenyl-2-picrylhydrazy), and ABTS +· (2, 2’-azinobis-3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) were used to measure antioxidation and analyze relationship between polyphenol content and antioxidation. [Result] Among the fourteen varieties of balsam pear, free, bound and total phenols were 157.58 -382.92, 6.46 -54 and 175.27 -413.79 mg GAE/100 g DW; coefficients of variance were 23.50% , 61.04% and 21.58%, respectively; free phenol accounted for 91.34% of total phenol and bound phenol accounted for 8.66% ; contents of total flavone for the fourteen varieties were from 8.97 to 18.22 mg CE/100 g DW and the coefficient was at 22.80%; vanillic aldehyde acid, epicatechin and rutin differed in contents among different varieties, which changed in 1.83-9.29, 35.17-114.52 and 0.91-4.53 mg/100 g DW and the coefficients were 43.85%, 26.97% and 33.09%; FRAP antioxidation was at 272.16 -713.32 mg TE/100 g DW and coefficient at 27.67% ; IC 50 of DPPH and ABTS +· clearance were 11.43-34.14 and 21.57-119.71 mg GAE/100 g DW and coefficients were at 35.10% and 63.75% , accordingly; content of total phenol was of extremely positive correlation with FRAP (P0.01) and of extremely negative correlation with IC 50 of DPPH and ABTS + · clearance (P0.01). [Conclusion] Contents of phenolic compounds and antioxidation are of significant genotype differences; and phenolic substance and antioxidation are mainly in free form and phenolic substance is the major basis for antioxidation.
基金National Natural Science Foundation of China(52071274)Key Research and Development Projects of Shaanxi Province(2023-YBGY-442)Science and Technology Nova Project-Innovative Talent Promotion Program of Shaanxi Province(2020KJXX-062)。
文摘To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.
基金National Natural Science Foundation of China(52272075,52472053)Research Fund of Youth Innovation Promotion Association of CAS,China(2021190)Defense Industrial Technology Development Program(JCKY2021130B007)。
文摘Carbon fiber-reinforced carbon aerogel(C/CA)composites are one of the most promising candidates for applications requiring both thermal insulation and load bearing capabilities.The preparation of anti-oxidation coatings on C/CA to address its susceptibility to oxidation is a feasible approach to promote its application in oxidative environments.However,the currently reported coatings on C/CA mainly focus on improving the ablation performance and coating preparation process typically necessitating high-temperature heat treatment.This procedure can increase its thermal conductivity and reduce its thermal insulation ability.In this study,a series of ceramic-resin coatings were fabricated on C/CA through a simple slurry brushing-drying approach at room temperature.The effects of phenolic resin content on the coating structure,residual stress,thermal shock,and oxidation behaviors were investigated.Due to the adhesive properties and curing-induced shrinkage,the PR-7.5 coating(containing 7.5%(in mass)phenolic resin in the slurry)exhibits bonding strength close to fracture strength of the substrate and residual compressive stress of 0.853 GPa,which is beneficial for resisting thermal shock cracking.However,excessive resin content(PR-10.0 containing 10.0%(in mass)phenolic resin in the slurry)induces tensile stress due to uneven curing shrinkage,thereby leading to thermal shock cracking.Meanwhile,oxidation tests reveal significantly reduced weight losses for PR-7.5(17.46%at 800℃/100 min,8.15%at 1000℃/120 min,3.15%at 1200℃/120 min)versus uncoated C/CA’s 44.60%loss at 800℃/20 min.This work provides a brand-new and simple approach to improving the anti-oxidation performance of C/CA and expands its application in mild oxidative environments.
基金supported by the Key R&D Program of Shandong Province,China(No.2025CXGC 010412)the National Key Research and Development Program of China(No.2022YFB3709300)the National Natural Science Foundation of China(No.U21A2048).
文摘The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical properties,can significantly enhance the oxidation resistance of Mg alloys.Based on our previous study,we conclude that REs such as Gd,Y,and Ce enhance the oxidation resistance of Mg-RE alloys.This article comprehensively reviews recent research progress on high-temperature oxidation behavior and the potential mechanism in Mg-RE alloys.Based on the thermodynamic and kinetic analyses,the evolution of the complex oxide system formed during the high-temperature oxidation of Mg-RE alloys is first summarized.The diffusion behavior and concentration control mechanisms of REs during the oxidation process and how these mechanisms affect the sustained growth of the oxide film and antioxidant properties were elucidated.Moreover,the different structures of the oxide films were classified,and their properties were discussed.Finally,this paper introduces the applications of commonly used REs in Mg alloys and frontier research on their oxidation mechanisms.Based on the above review,we propose that future research perspectives can be explored in terms of expanding the experimental temperature range for oxidation tests,optimizing the chemical composition by adding trace REs to study their synergistic mechanism,revealing the underlying oxidation mechanism through advanced in situ microscopic characterization methods,and investigating the mechanical properties of oxide films using diverse approaches.
文摘Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected.
基金Supported by Zhaoqing University-Zhanjiang Institute for Food and Drug Control Joint Laboratory(52).
文摘[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the raw material,the effects of ethanol concentration,ultrasonic temperature,time,and solid-to-liquid ratio on the total flavonoid yield were investigated through single-factor and orthogonal experiments.[Results]All factors had a significant effect on the yield.The optimized conditions were determined as follows:ethanol concentration 75%,ultrasonic temperature 60℃,ultrasonic time 30 min,and solid-to-liquid ratio 1:50(g/ml).Under these conditions,the total flavonoid yield reached 3.08%.Evaluation of antioxidant activity revealed that the extract exhibited superior scavenging rates against both DPPH and hydroxyl radicals compared with the standard reference compound BHT.[Conclusions]This study holds significant importance for elucidating the pharmacological mechanisms of flavonoids in H.undatus and for expanding their application in medicine and health products.
基金Financial support from the National Natural Science Foundation of China(32502106)One health Interdisciplinary Research Project,Institute of One Health Science,Ningbo University(NBUOH202502)the Ningbo Top Talent Project(215-432094250).
文摘The antioxidant activity of selenium-containing soybean peptides(SePPs)has been previously demonstrated,despite their limited absorption in the small intestine.This study investigates the antioxidant mechanism of a selenium-containing tetrapeptide,Ser-Phe-Gln-SeM(SFQSeM),identified from SePPs,with particular emphasis on its interaction with the intestinal microbiota and its role in modulating host antioxidant defenses.The effects of SFQSeM were evaluated in a D-galactose-induced oxidative stress model and an antibiotictreated mouse model.SFQSeM supplementation significantly reduced the oxidative stress in D-galactosetreated mice.It also promoted the growth of beneficial bacteria and increased the levels of acetate,butyrate and lactate in the intestine(P<0.05).In the antibiotic-treated mouse model,depletion of the intestinal microbiota significantly reduced hepatic glutathione peroxidase(GSH-Px)activity(26.6%)and glutathione peroxidase 1(GPx-1)expression(48.77%)compared to normal mice supplemented with SFQSeM(P<0.05).In contrast to Na_(2)SeO_(3)and selenomethionine,SFQSeM effectively restored the diversity of the intestinal microbiota disrupted by antibiotics.Lactobacillus,Lachnospiraceae_NK4A136_group,and Muribaculaceae were identified as predominant bacteria in the SFQSeM group,and were strongly associated with increased hepatic GSH-Px activity and GPx-1 mRNA expression(P<0.05).In conclusion,intestinal microbiota enhances the antioxidant efficacy of SFQSeM by modulating microbial composition,producing active metabolites,and converting SFQSeM into a bioactive form of selenium.
基金Supported by Scientific Research Project of the Guangxi Zhuang Autonomous Region Administration of Traditional Chinese Medicine(GXZYA20220105).
文摘[Objectives]To evaluate the in vitro antibacterial,antioxidant,andα-glucosidase inhibitory activities of the ethanol total extract and four different polarity fractions(n-butanol,ethyl acetate,petroleum ether,and water)of Pilea peltata Hance,so as to provide a reference for its further development and research.[Methods]The antibacterial activity of P.peltata was evaluated in vitro by determining the minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of its ethanol total extract and four different polarity fractions against seven test bacterial strains using the broth microdilution method.The in vitro antioxidant activity was investigated through DPPH radical,hydroxyl radical,and superoxide anion radical scavenging assays,with vitamin C(Vit C)as the positive control and the half maximal scavenging concentration(IC 50)as the evaluation indicator.The in vitroα-glucosidase inhibitory activity was assessed by measuring the peak area of p-nitrophenol(PNP),the hydrolysis product of 4-nitrophenylα-D-glucopyranoside(PNPG),via high-performance liquid chromatography(HPLC),using the half maximal inhibitory concentration(IC 50)as the evaluation indicator.[Results]Both the ethanol total extract and the four different polarity fractions of P.peltata exhibited significant in vitro anti-Streptococcus pneumoniae activity.The DPPH radical scavenging capacities of the ethanol total extract and the various fractions were all weaker than that of VitC,with the order of efficacy being:n-butanol fraction>ethanol total extract>ethyl acetate fraction>petroleum ether fraction>aqueous fraction.For hydroxyl radical scavenging activity,the efficacy order of P.peltata fractions was:n-butanol extract>ethyl acetate extract>ethanol total extract>petroleum ether extract>aqueous extract.Notably,the n-butanol fraction(IC 50=0.068±0.001)demonstrated stronger activity than VitC(IC 50=0.097±0.001).The activity of the ethyl acetate fraction(IC 50=0.096±0.004)was comparable to that of VitC(IC 50=0.097±0.001).The superoxide anion scavenging capacities of the ethanol total extract and different polarity fractions from P.peltata were all weaker than that of VitC,with the order of efficacy being:n-butanol fraction>ethyl acetate fraction>ethanol total extract>petroleum ether fraction>aqueous fraction.The ethanol total extract and aqueous fraction of Pilea peltata showed no significant in vitroα-glucosidase inhibitory activity.Compared with the acarbose group,the IC 50 values of the ethyl acetate fraction and the n-butanol fraction both showed highly significant differences(P<0.01).[Conclusions]This study provides an experimental basis for the pharmacodynamic study and active component study of P.peltata.
基金supported by the SECIHTI project Ciencia Basica y de Frontera(No.CBF2023-2024-1141)https://secihti.mx/(accessed on 01 August 2025).
文摘Objectives:Oxidative stress(OS)plays a pivotal role in chronic and neurodegenerative diseases,which has sparked interest in molecules that modulate redox-regulating enzymes.Melatonin and its metabolites exhibit antioxidant properties;however,their molecular mechanisms of enzymatic and transcriptional modulation remain unclear.This study aimed to investigate,through an exploratory in silico approach,the interactions of melatonin and related compounds with OS-related enzymes to generate hypotheses about their role in cellular redox control.Methods:A rational selection of antioxidant,pro-oxidant,and transcriptional targets was performed.Ligands were optimized at the DFT level(M05-2X/6-311+G(d,p))and docked to OS related enzymes.Docking results were analyzed using polygenic antioxidant indices(PAOX)and a similarity interaction index(SSI).Molecular dynamics simulations of selected complexes provided additional insight into potential ligand-protein interaction mechanisms.Results:In silico analyses revealed that N1-acetyl-5-methoxykynuramine(AMK),N1-acetyl-N2-formyl-5-methoxykynuramine(AFMK),and 3-hydroxymelatonin(3OH-M)could partially inhibit pro-oxidant enzymes such as neuronal nitric oxide synthase(nNOS),5-lipoxygenase(5-LOX),thioredoxin reductase(TrxR),and nicotinamide adenine dinucleotide phosphate oxidase(NOX5).The N-(2-(2-acetyl-6,7-dihydroxy-1H-indol-3-yl)ethyl)acetamide(IIcD)and N-(2-(6-hydroxy-7-mercapto-5-methoxy-1H-indol)ethyl)acetamide(dM38)derivatives could potentially stabilize superoxide dismutase(SOD1)and catalase(CAT)enzymes,respectively.Finally,AFMK and dM38 showed consistent interactions with transcriptional regulators,particularly peroxisome proliferator-activated receptor alpha(PPARα)and Kelchlike ECH-associated protein 1(KEAP1).Conclusion:These studies about melatonin-related compounds support a multifactorial profile of redox modulation and provide mechanistic hypotheses for future experimental validation.Among these approaches,the interaction-similarity index is introduced as a novel tool to facilitate the identification of promising redox-active candidates.
基金supported in part by grants from Biological Breeding-National Science and Technology Major Project(2023ZD04040)Jiangsu Key Research and Development Program(BE2022384)Collaborative Innovation Center for Modern Crop Production co-sponsored by Province and Ministry(CIC-MCP)(No.10).The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.
文摘Carotenoids are natural pigments that are widely distributed in the flowers,fruits,and seeds of many plant species.These compounds not only endow diverse colors but also exhibit antioxidant,immune-modulatory,anti-aging,and photoprotective properties.Although carotenoid metabolism has been studied extensively in microbial and plant science,the genetic mechanisms underlying carotenoid metabolism in cotton remain underexplored.Here,we isolated gene GbDYA that regulates a dark-yellow anther color by map-based cloning using a BC1F1 population derived from a cross of Gossypium barbadense acc.Hai7124 with dark-yellow anthers and G.hirsutum acc.TM-1 with light-yellow anthers backcrossed with TM-1.GbDYA encodes phytoene synthase,a key rate-limiting enzyme in the carotenoid biosynthesis pathway.A long terminal repeat retrotransposon in the first exon of GhDYA(an ortholog of GbDYA in G.hirsutum acc.TM-1)caused loss of function and led to the light-yellow anther color.GbDYA is predominantly expressed in the early stages of anther development.Transcriptome,RT-qPCR and KEGG enrichment analyses revealed that GbDYA influences the synthesis and accumulation of carotenoids in anthers by modulating expression of key genes in the carotenoid biosynthesis pathway.Integrated transcriptomic and metabolomic analyses indicated that the accumulation of lutein,violaxanthin,antherxanthin,cryptoxanthin,zeaxanthin,andβ-carotene contributed to yellow coloration of anthers.Dual-luciferase and yeast one-hybrid assays confirmed that transcription factor GbMYB105(GB_A11G3511)binds to the promoter of GbDYA and activates its expression.High-temperature stress treatment indicated that carotenoids accumulation in anthers enhances pollen antioxidant activity.This study unravels the role of GbDYA in conferring the anther coloration,and provides the potential utilization by modulating accumulation of carotenoids in anthers to enhance pollen viability in high-temperature tolerance breeding in cotton.
文摘Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive compounds such as flavonoids and alkaloids,which influence multiple biological pathways.This review aims to summarise and critically analyse recent findings on the pharmacological properties of Passiflora incarnata L.,focusing on its neuropsychiatric,antioxidant,antimicrobial,and anticancer activities.A targeted literature search was conducted in PubMed,Scopus,Web of Science,and Google Scholar for peer-reviewed publications between 2000 to 2025.Relevant articles were screened,and a more appropriate article related to the objective of the review was selected.Some classical papers are also cited as per the requirement of the topic.Passiflora incarnata L.showed multifunctional medicinal properties with various applications in neuropsychiatry,oxidative stress management,antimicrobial agent,and as an anticancer agent.The U.S.Food and Drug Administration categorizes passionflower extracts as“generally recognized as safe”.However,most evidence remains preclinical,with methodological variation limiting generalisation.Standardised formulation,robust clinical trials,and in-depth in vivo studies are essential to establish its therapeutic relevance and safety in modern medicine.
基金supported by the National Key Research and Development Program of China(2024YFA1612900)the National Natural Science Foundation of China(Grant No.52103365 and No.12375270)the Guangdong Innovative and Entrepreneurial Research Team Program,China(Grant No.2021ZT09L227).
文摘Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.
基金supported by the National Natural Science Foundation of China(No.82073721)Major Basic Research Project of the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.23KJA310003).
文摘Asplactones A-E(1-5),five unique diphenyl ether hybrids,along with two rare spiro-diphenyl ethers,aspviolaceols A(6)and B(7),were isolated and characterized from Aspergillus sp.F1-8A,an endophytic fungus associated with the parotoid glands of Bufo gargarizans Cantor.Compounds 1-5 represent the first examples of diphenyl ether hybrids fused with unusual moieties,including conjugatedγ-butyrolactone and cyclopentenone.Compounds 6 and 7 are the first known natural spiro-diphenyl ethers,with 6 featuring an uncommon 6/6/6/6-membered carbon skeleton,and 7 possessing a distinct 6/6/6/6/6/6-membered diphenyl ether spiro-heterodimer carbon framework.Structural elucidation was performed using a combination of spectroscopic techniques,X-ray crystallography,and quantum-chemical calculations,and plausible biosynthetic pathways were proposed.Biologically,compounds 1,2,4,6,and 7 exhibited antioxidant activity comparable to or surpassing that of vitamin C in 1,1-diphenyl-2-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate)(ABTS),and ferric reducing power assays.They also significantly improved cell viability in H2O2-induced oxidative injury assays using A549 cells.