Although enantiomers of 2-phenylpropionic acids (2-PPAs), or profens are important group of nonsteroidal anti-inflammatory drugs (NSAIDs) and have been in clinical use for many years, there is no literature covering i...Although enantiomers of 2-phenylpropionic acids (2-PPAs), or profens are important group of nonsteroidal anti-inflammatory drugs (NSAIDs) and have been in clinical use for many years, there is no literature covering its binding interaction in particular with cyclodextrins. NSAIDs are marketed as racemates, chiral discrimination and knowledge of enantiomeric bioavailability is essential. Circular dichroism (CD) spectroscopy is the technique of choice for elucidating chirality and monitoring and characterizing molecular recognition phenomena in solution. Methods em-ploying the fundamentals of the simultaneous measurements of absorbance and CD and a novel efficient titration method have been developed to study the binding of β-Cyclodextrin (β-CyD) and the two enantiomers of 2-PPA as a function of pH. The effect on physicochemical properties and bioavailability was investigated. The binding constant, stoichiometry and pKa for both the free and the bound drugs were determined using a Levenburg-Marquadt non-linear equation. The exact nature of the enantiomer discriminating interactions by cyclodextrins (CyDs) is not well understood. In this work, the interactions and co-conformations of both enantiomers of 2-PPA with β-CyD were explained and es-timated using spectroscopic variations upon complexation. The results indicated a change in the physicochemical prop-erties of 2-PPAs upon complexation and highlighted the enantioselective binding of β-CyD as a function of pH. The charge on the vip molecule and its stereochemistry are of great importance in regulating the stability of the vip/β-CyD complexes;hence the bioavailability of drugs. This work elucidates 2-PPAs/β-CyD binding interactions and highlights the effect of β-CyD on drugs with an effective novel method for binding titration and the potential of the simultaneous measurements of absorbance and CD in future chiral drug interactions studies.展开更多
As the only naturally occurring stable derivative of L-ascorbic acid(AA;vitamin C),2-O-β-D-glucopyranosyl-L-ascorbic acid(AA-2βG)is hydrolyzed in vivo to release active AA.AA-2βG exhibits strong antioxidant and ant...As the only naturally occurring stable derivative of L-ascorbic acid(AA;vitamin C),2-O-β-D-glucopyranosyl-L-ascorbic acid(AA-2βG)is hydrolyzed in vivo to release active AA.AA-2βG exhibits strong antioxidant and antiphotoaging effects comparable to those of AA,and it plays a key role in maintaining organismal health.Owing to its superior stability and bioavailability,AA-2βG is considered as a promising,longer-lasting natural alternative to conventional vitamin C.It was first identified and is particularly abundant in Lycii Fructus(Gouqizi in Chinese)but has been detected in several crop plants.This review offers a comprehensive overview of recent advances in AA-2βG research,covering key aspects including discovery,structure,natural sources,extraction and detection methods,chemical and in vitro enzymatic synthesis,biosynthetic pathways,as well as applications in health care,skin care,and functional foods.Additionally,we highlight strategies for leveraging plant resources and enhancing AA-2βG biosynthesis,which are expected to accelerate future research and support the sustainable development and utilization of AA-2βG and other high-value natural products.展开更多
Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performa...Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performance indicators such as catalytic activity,selectivity,and stability can be effectively optimized.As a result,they become essential parameters that must be considered in the design and development of high-efficiency catalysts.This study proposes a surface engineering method to accurately control the concentration of surface LA and LB sites in defect-laden In_(2)O_(3-x)(OH)_(y)(denoted as N-n%-IO),establishing three types of LB/LA stoichiometric ratios with different photocatalytic CO_(2)hydrogenation performances.It is demonstrated that the LB-rich system(LB/LA>1)shows suppressed activity.In contrast,the balanced stoichiometric ratio system(LB/LA=1)attains an optimal methanol yield(179.79μmol g^(-1)h^(-1))and selectivity(43.67%),while the LA-rich system(LB/LA<1)exhibits the best CO production rate(1913.76μmol g^(-1)h^(-1))and selectivity(94.96%).Systematic experiments disclose that the balanced LB/LA system with adjacent surface frustrated Lewis pairs(SFLPs)can effectively facilitate the adsorption/activation of reactants,stabilize intermediates,and regulate the dynamic behavior of photo-generated carriers.However,the imbalanced LB/LA systems either lack necessary active sites or can only follow an oxygen vacancy-mediated pathway during photocatalytic CO_(2)hydrogenation.This work offers a comprehensive understanding of the crucial functions of surface Lewis acid/base sites in the product distribution of solar-driven CO_(2)reduction.展开更多
Background:Mastitis seriously affects the mammary health of humans and animals.Studies have found that inflammation and oxidative stress play key roles in the occur-rence and development of mastitis.Therefore,in-depth...Background:Mastitis seriously affects the mammary health of humans and animals.Studies have found that inflammation and oxidative stress play key roles in the occur-rence and development of mastitis.Therefore,in-depth research on related molecular mechanisms is of great significance.Methods:Postpartum mice were anesthetized with pentobarbital and administered lipopolysaccharide to develop the mouse mastitis model.Proteomic analysis was per-formed to compare protein expression in mitochondria-associated endoplasmic retic-ulum membranes(MAM)from two mouse mammary gland groups.Western blot was used to detect the expression of MAM-related proteins in mitochondria.AlphaFold3 was used to predict the molecular structures of phosphofurin acidic cluster sorting protein 2(PACS2)and mitofusin 2(MFN2)and their interaction levels.The MFN2-PACS2 interaction was investigated using co-immunoprecipitation and small interfer-ing RNA.Results:The results showed that the inflammation level in the mammary gland tissue of mice with mastitis significantly increased,the total antioxidant capacity decreased,and the expression of MAM-related proteins MFN2 and PACS2 was significantly downregulated.In cell experiments,overexpression of MFN2 can inhibit inflamma-tion and oxidative stress responses,and promote the interaction between MFN2 and PACS2 to affect the formation of MAMs.Conclusion:In summary,this study suggests that mastitis can alter the expression of MAM-related proteins in mouse breast tissue.The interaction between MFN2 and PACS2 regulates the formation of MAMs.Overexpression of MFN2 can promote the formation of MAMs and inhibit inflammation and oxidative stress response in mam-mary epithelial cells.Our results provided a new theoretical basis and potential thera-peutic targets for the prevention and treatment of mastitis.展开更多
The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative...The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative solution in a pure acidic system,but the catalyst layer in direct contact with the hydrated proton environment usually leads to H_(2)evolution dominating.Herein,we show that polydimethyldiallyl-ammonium-chloride-coated Ag(Ag@PDDA)electrode exhibits outstanding performance with a FE of 86%,a single-pass conversion of 72%,and a stability of 28 h for CO production in pure-acid MEA compared with ammonium poly(N-methyl-piperidine-co-pterphenyl)decorated Ag(Ag/QAPPT)and cetyltrimethylammonium bromide decorated Ag(Ag/CTAB).The in situ ATR-SEIRAS reveal that PDDA creates a positive charge-rich protective outer layer and an N-rich hybrid inner layer,which not only suppresses the migration of H+during the electrolysis process and blocks the direct contact between H2O and Ag catalyst,but also promotes the generation from CO_(2)to*COOH in a pure-acid system.This work highlights the importance of polyelectrolyte engineering in regulating the electrocatalytic interface and accelerates the development of proton exchange membrane CO_(2)electrolysis.展开更多
（R）-2-hydroxy-3-phenylpropionic acid （PIP,） is an ideal antimicrobial compound with broad-spectrum activity against a wide range of Gram-positive bacteria, some Gram-negative bacteria, and fungi. We studied the bi...（R）-2-hydroxy-3-phenylpropionic acid （PIP,） is an ideal antimicrobial compound with broad-spectrum activity against a wide range of Gram-positive bacteria, some Gram-negative bacteria, and fungi. We studied the bioconversion of phenylpyruvate （PPA） to PLA using whole recombinant Escherichia coli cells in a series of buffer/organic solvent systems. Octane was found to be the best organic solvent. The optimum volume ratio of the water phase to the n-octane phase, conversion temperature, substrate concentration, and cell concentration were 6：4, 40 ℃, 12.5 g/L, and 30 g/L wet cells, respectively. Under the optimized conditions, the average PLA productivity in the aqueous/ n-octane system was 30.69% higher than that in the aqueous system, and 32.31 g/L PLA was obtained with the use of a stirred reactor （2-L scale）. Taken together, our findings indicated that PLA biosynthesis was more efficient in an aqueous/n-octane biphasic system than in a monophasic aqueous system. The proposed biphasic system is an effective strategy for enhancing PLA yield and the biosynthesis of its analogues.展开更多
Photoinduced[2+2]cycloaddition of biomass-derived cycloolefin is a promising approach to synthesize high-energy bio-fuels,however,the conversion efficiency and selectivity are still low.Herein,we provide an acid-promo...Photoinduced[2+2]cycloaddition of biomass-derived cycloolefin is a promising approach to synthesize high-energy bio-fuels,however,the conversion efficiency and selectivity are still low.Herein,we provide an acid-promoted photocycloaddition approach to synthesize a new kind of spiral fuel from biomass-derived cyclohexanone (CHOE) and camphene (CPE).BrΦnsted acids show higher catalytic activity than Lewis acids,and acetic acid (HOAc) possesses the best catalytic performance,with CHOE conversion up to 99.1%.Meanwhile,the HOAc-catalytic effect has been confirmed for[2+2]photocycloaddition of other biomass-derived ketenes and olefins.The catalytic mechanism and dynamics have been investigated,and show that HOAc can bond with C=O groups of CHOE to form H–CHOE complex,which leads to higher light adsorption and longer triplet lifetime.Meanwhile,H–CHOE complex reduces the energy gap between CHOE LUMO and CPE HOMO,shortens the distance of ring-forming atoms,and then decreases the energy barrier (from 103.3 kcal mol^(-1)to 95.8 kcal mol^(-1)) of rate-limiting step.After hydrodeoxygenation,the targeted bio-spiral fuel shows high density of 0.992 g cm^(-3),high neat heat of combustion of 41.89 MJ L^(-1),low kinetic viscosity of 5.69 mm^(2)s^(-1)at 20℃,which is very promising to serve as high-performance aerospace fuel.展开更多
The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain functio...The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders.展开更多
In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation...In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation recovery of bastnaesites can be achieved more than 90%when the aeration rate is 40 mL/min,the rotational speed is 200 r/min,the H205 dosage is 120 mg/L,and the pulp pH ranges from 7 to 9.The action mechanism of H205 on the surface of bastnaesite was studied by simultaneous thermogravimetry and differential scanning calorimetry(TG-DSC),Zeta potential measurements,Fourier transform-infrared spectra(FT-IR)and X-ray photoelectron spectroscopy(XPS).These analysis results show that under suitable flotation conditions,H205 has an obvious adsorption phenomenon on the surface of bastnaesite.The adsorption involves electrostatic interactions and chemical interactions,namely H205 has a strong collecting ability of bastnaesite due to the synergism of electrostatic adsorption and chemical adsorption.This study systematically reveals the flotation behavior and adsorption mechanism of H205 on the surface of bastnaesite,and provides useful theoretical guidance for efficient flotation separation of bastnaesite.展开更多
Carbon dioxide(CO_(2))marine sequestration by hydrate method is considered as one of the options to effectively achieve carbon reduction.However,the slow rate of hydrate formation becomes a major limiting factor.In vi...Carbon dioxide(CO_(2))marine sequestration by hydrate method is considered as one of the options to effectively achieve carbon reduction.However,the slow rate of hydrate formation becomes a major limiting factor.In view of the gas-water mass transfer problem which is the main obstacle,this paper explored the amphiphilic amino acids to promote the formation of CO_(2)hydrate and used low-field nuclear magnetic resonance(LNMR)to conduct an innovative study on its kinetics and spatiotemporal distribution.By comparing the promotion performance of L-methionine(L-met),L-cysteine(L-cys),and L-valine(L-val),the comprehensive kinetic promotion ability of L-met was the highest,reducing the induction time by 60.0%,achieving the maximum water conversion of about 57.0%within only 1 h,and reaching a final CO_(2)storage efficiency of 84.6%.LNMR results showed that hydrates were preferentially formed in large and medium pores in the reservoir region.Interestingly,we found that the combined effect of hydrophilic groups and the hydrophobic side chain of L-met not only promoted the rearrangement of water molecules and provided more nucleation sites,but also created a localized CO_(2)supersaturated environment and facilitated gas-water redistribution.Meanwhile,L-met promoted the formation of a hydrate porous structure to ensure the continuous formation of hydrates.This study innovatively explored CO_(2)hydrate formation behavior in amphiphilic amino acids and laid a theoretical foundation for the realization of CO_(2)marine sequestration by hydrate method.展开更多
Improving salt tolerance and mitigating senescence in the presence of high salinity are crucial for sustaining agricultural productivity.Previous research has demonstrated that hydrogen peroxide(H_(2)O_(2)),specifical...Improving salt tolerance and mitigating senescence in the presence of high salinity are crucial for sustaining agricultural productivity.Previous research has demonstrated that hydrogen peroxide(H_(2)O_(2)),specifically H_(2)O_(2)derived from roots and mediated by the respiratory burst oxidase homolog(NADPH),plays a significant role in regulating ion and plant hormone homeostasis in glycophytic plants,such as Arabidopsis.However,the extent to which root-derived H_(2)O_(2)fulfils similar functions in halophytic plants remains uncertain.Therefore,our study aimed to explore the potential contribution of root-sourced H_(2)O_(2)in delaying leaf senescence induced by high salinity,utilizing seashore paspalum as a model halophytic plant.The application of the NADPH-oxidase inhibitor DPI,coupled with a series of leaf senescence analyses,we revealed that root-derived H_(2)O_(2)significantly retards salt-induced leaf senescence.Furthermore,through the application of hormone analysis,lipidomics,ionomics,Non-invasive Micro-test Technology(NMT),and transcriptomics,we established that NADPH-dependent H_(2)O_(2)induced by salt stress in the roots was indispensable for maintaining the balance of the aging hormone,jasmonic acid(JA),and sodium ion homeostasis within this halophytic plant.Finally,by utilizing AtrbohD Arabidopsis mutants and virus-induced gene silencing(VIGs)in Paspalum vaginatum,we demonstrated the pivotal role played by root-sourced H_(2)O_(2)in upholding JA homeostasis and regulating JA-triggered leaf senescence in P.vaginatum.This study offers novel insights into the mechanisms that govern plant leaf senescence and its response to salinity-induced stress.展开更多
The catalytic oxidation of HMF involves a cascading reaction with multiple intermediate products,making it crucial to enhance the oriented adsorption capacity of specific functional groups for accelerating the entire ...The catalytic oxidation of HMF involves a cascading reaction with multiple intermediate products,making it crucial to enhance the oriented adsorption capacity of specific functional groups for accelerating the entire process.To achieve the efficient selective oxidation of HMF to FDCA,a series of NiCo_(2)O_(4)catalysts with different morphologies,such as flaky,echinoids,pompon and corolla,were prepared and characterized by XRD,SEM,TEM,BET,XPS,and FTIR.Among the four catalysts,flaky NiCo_(2)O_(4)exhibited the most excellent catalytic activity and stability,with a FDCA yield of 60.1%within 12 h at 80℃without alkali participation.The excellent performance of flaky NiCo_(2)O_(4)catalyst is attributed to the oxygen vacancies and acid sites generated by the exposed(400)facets.The oxygen vacancies and acid sites on the catalyst surface can precisely adsorb-CHO and-CH_(2)-OH of HMF,respectively,and this synergistic effect promotes the efficient production of FDCA.This work is of great significance for fundamentally study the effect of micro-topography or crystal-plane reaction properties on surfaces.展开更多
Electrochemical carbon dioxide reduction reaction(CO_(2)RR)converts CO_(2) into valuable chemicals by consuming renewable electricity at mild conditions,making it a promising approach to achieving carbon neutrality.Ho...Electrochemical carbon dioxide reduction reaction(CO_(2)RR)converts CO_(2) into valuable chemicals by consuming renewable electricity at mild conditions,making it a promising approach to achieving carbon neutrality.However,the reaction of CO_(2) with hydroxide ions to form carbonates leads to low carbon utilization and energy efficiency in near-neutral or alkaline CO_(2)RR.The high concentration of protons in acidic media can effectively mitigate carbonate formation and deposition,thereby significantly minimizing carbon loss and energy consumption.Unfortunately,hydrogen evolution reaction(HER)is more kinetically favorable than CO_(2)RR in acidic media.Herein,we comprehensively overview recent progress in acidic CO_(2)RR and propose two strategies derived from the competing reaction pathways of HER and CO_(2)RR:one focuses on regulating the H+mass transport,while the other aims to modulate the intrinsic kinetic activity of CO_(2)RR.The two strategies are designed to compete for the limited active sites on the catalyst surface,inhibit side reactions,and enhance the activity and selectivity of CO_(2)RR.The representative approaches include modulating the interface electric field,constructing a local alkaline environment,and regulating competing adsorption sites.Finally,we also review the technical challenges and future perspectives of acidic CO_(2)RR coupled with membrane electrode assemblies(MEAs).展开更多
Two different Mn-Ce-O_(x)/TiO_(2) catalysts were prepared by ordinary impregnation(denoted as MCT) and citric acid assisted impregnation(denoted as MCT-CA) methods,respectively.Excellent NOxremoval is achieved over MC...Two different Mn-Ce-O_(x)/TiO_(2) catalysts were prepared by ordinary impregnation(denoted as MCT) and citric acid assisted impregnation(denoted as MCT-CA) methods,respectively.Excellent NOxremoval is achieved over MCT-CA for selective catalytic reduction with NH3(NH_(3)-SCR),and 100% NOxconversion is obtained at 125℃ under weight hour space velocity(WHSV) of 80000 mL/(gcat·h).Particularly,100% NOxis converted on MCT-CA in the presence of 10 vol% H2O at 175℃.As H2O and SO2coexist in the reaction system for 9 h,NO_(x) conversion can still be maintained>90%,much higher than that(22%) of MCT.A series of characterization results indicates that MCT-CA exhibits a larger BET specific surface area,pore volume,and pore size,which enhances the dispersion of Mn and Ce oxides and promotes the rapid adsorption of reactants and desorption of products.Additionally,MCT-CA possesses more Mn^(4+),Ce^(3+),chemisorbed oxygen species,and stronger reducibility,facilitating the co nversion of NO to NO_(2).Specially,the amount of active NH_(3) species and active nitrate species on MCT-CA is much more than that over MCT,The combined effect of the aforementioned factors devotes to the excellent low-temperature SCR performance and tolerance to H2O/SO2over MCT-CA.展开更多
文摘Although enantiomers of 2-phenylpropionic acids (2-PPAs), or profens are important group of nonsteroidal anti-inflammatory drugs (NSAIDs) and have been in clinical use for many years, there is no literature covering its binding interaction in particular with cyclodextrins. NSAIDs are marketed as racemates, chiral discrimination and knowledge of enantiomeric bioavailability is essential. Circular dichroism (CD) spectroscopy is the technique of choice for elucidating chirality and monitoring and characterizing molecular recognition phenomena in solution. Methods em-ploying the fundamentals of the simultaneous measurements of absorbance and CD and a novel efficient titration method have been developed to study the binding of β-Cyclodextrin (β-CyD) and the two enantiomers of 2-PPA as a function of pH. The effect on physicochemical properties and bioavailability was investigated. The binding constant, stoichiometry and pKa for both the free and the bound drugs were determined using a Levenburg-Marquadt non-linear equation. The exact nature of the enantiomer discriminating interactions by cyclodextrins (CyDs) is not well understood. In this work, the interactions and co-conformations of both enantiomers of 2-PPA with β-CyD were explained and es-timated using spectroscopic variations upon complexation. The results indicated a change in the physicochemical prop-erties of 2-PPAs upon complexation and highlighted the enantioselective binding of β-CyD as a function of pH. The charge on the vip molecule and its stereochemistry are of great importance in regulating the stability of the vip/β-CyD complexes;hence the bioavailability of drugs. This work elucidates 2-PPAs/β-CyD binding interactions and highlights the effect of β-CyD on drugs with an effective novel method for binding titration and the potential of the simultaneous measurements of absorbance and CD in future chiral drug interactions studies.
基金funded by the National Key Research and Development Program(Nos.2023YFC3504104 and 2024YFD2100700)the Fundamental Research Funds for the Central public welfare research institutes(No.ZZ13-YQ-101)Scientific and technological innovation project of China Academy of Chinese Medical Sciences(No.CI2023E002-Y-28).
文摘As the only naturally occurring stable derivative of L-ascorbic acid(AA;vitamin C),2-O-β-D-glucopyranosyl-L-ascorbic acid(AA-2βG)is hydrolyzed in vivo to release active AA.AA-2βG exhibits strong antioxidant and antiphotoaging effects comparable to those of AA,and it plays a key role in maintaining organismal health.Owing to its superior stability and bioavailability,AA-2βG is considered as a promising,longer-lasting natural alternative to conventional vitamin C.It was first identified and is particularly abundant in Lycii Fructus(Gouqizi in Chinese)but has been detected in several crop plants.This review offers a comprehensive overview of recent advances in AA-2βG research,covering key aspects including discovery,structure,natural sources,extraction and detection methods,chemical and in vitro enzymatic synthesis,biosynthetic pathways,as well as applications in health care,skin care,and functional foods.Additionally,we highlight strategies for leveraging plant resources and enhancing AA-2βG biosynthesis,which are expected to accelerate future research and support the sustainable development and utilization of AA-2βG and other high-value natural products.
基金supported by the National Natural Science Foundation of China(22172086,22105117)the Taishan Scholars Program of Shandong Province(202103064)the Major Basic Research Project of Shandong Province(ZR2021ZD06)。
文摘Lewis acid(LA)and Lewis base(LB)sites on catalyst surfaces play a pivotal role in catalytic reactions.By precisely modulating the type,density,and spatial distribution of these Lewis acid/base sites,catalytic performance indicators such as catalytic activity,selectivity,and stability can be effectively optimized.As a result,they become essential parameters that must be considered in the design and development of high-efficiency catalysts.This study proposes a surface engineering method to accurately control the concentration of surface LA and LB sites in defect-laden In_(2)O_(3-x)(OH)_(y)(denoted as N-n%-IO),establishing three types of LB/LA stoichiometric ratios with different photocatalytic CO_(2)hydrogenation performances.It is demonstrated that the LB-rich system(LB/LA>1)shows suppressed activity.In contrast,the balanced stoichiometric ratio system(LB/LA=1)attains an optimal methanol yield(179.79μmol g^(-1)h^(-1))and selectivity(43.67%),while the LA-rich system(LB/LA<1)exhibits the best CO production rate(1913.76μmol g^(-1)h^(-1))and selectivity(94.96%).Systematic experiments disclose that the balanced LB/LA system with adjacent surface frustrated Lewis pairs(SFLPs)can effectively facilitate the adsorption/activation of reactants,stabilize intermediates,and regulate the dynamic behavior of photo-generated carriers.However,the imbalanced LB/LA systems either lack necessary active sites or can only follow an oxygen vacancy-mediated pathway during photocatalytic CO_(2)hydrogenation.This work offers a comprehensive understanding of the crucial functions of surface Lewis acid/base sites in the product distribution of solar-driven CO_(2)reduction.
基金National Natural Science Foundation of China,Grant/Award Number:32302826 and 32372961Jilin Provincial Special Project for Health Research Talents,Grant/Award Number:2020SCZ40China Postdoctoral Science Foundation,Grant/Award Number:2023M740623。
文摘Background:Mastitis seriously affects the mammary health of humans and animals.Studies have found that inflammation and oxidative stress play key roles in the occur-rence and development of mastitis.Therefore,in-depth research on related molecular mechanisms is of great significance.Methods:Postpartum mice were anesthetized with pentobarbital and administered lipopolysaccharide to develop the mouse mastitis model.Proteomic analysis was per-formed to compare protein expression in mitochondria-associated endoplasmic retic-ulum membranes(MAM)from two mouse mammary gland groups.Western blot was used to detect the expression of MAM-related proteins in mitochondria.AlphaFold3 was used to predict the molecular structures of phosphofurin acidic cluster sorting protein 2(PACS2)and mitofusin 2(MFN2)and their interaction levels.The MFN2-PACS2 interaction was investigated using co-immunoprecipitation and small interfer-ing RNA.Results:The results showed that the inflammation level in the mammary gland tissue of mice with mastitis significantly increased,the total antioxidant capacity decreased,and the expression of MAM-related proteins MFN2 and PACS2 was significantly downregulated.In cell experiments,overexpression of MFN2 can inhibit inflamma-tion and oxidative stress responses,and promote the interaction between MFN2 and PACS2 to affect the formation of MAMs.Conclusion:In summary,this study suggests that mastitis can alter the expression of MAM-related proteins in mouse breast tissue.The interaction between MFN2 and PACS2 regulates the formation of MAMs.Overexpression of MFN2 can promote the formation of MAMs and inhibit inflammation and oxidative stress response in mam-mary epithelial cells.Our results provided a new theoretical basis and potential thera-peutic targets for the prevention and treatment of mastitis.
基金financial support of the National Natural Science Foundation of China(NSFC)(52394202,52021004,52301232,and 52476056)the Natural Science Foundation of Chongqing Province(2024NSCQ-MSX1109).
文摘The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative solution in a pure acidic system,but the catalyst layer in direct contact with the hydrated proton environment usually leads to H_(2)evolution dominating.Herein,we show that polydimethyldiallyl-ammonium-chloride-coated Ag(Ag@PDDA)electrode exhibits outstanding performance with a FE of 86%,a single-pass conversion of 72%,and a stability of 28 h for CO production in pure-acid MEA compared with ammonium poly(N-methyl-piperidine-co-pterphenyl)decorated Ag(Ag/QAPPT)and cetyltrimethylammonium bromide decorated Ag(Ag/CTAB).The in situ ATR-SEIRAS reveal that PDDA creates a positive charge-rich protective outer layer and an N-rich hybrid inner layer,which not only suppresses the migration of H+during the electrolysis process and blocks the direct contact between H2O and Ag catalyst,but also promotes the generation from CO_(2)to*COOH in a pure-acid system.This work highlights the importance of polyelectrolyte engineering in regulating the electrocatalytic interface and accelerates the development of proton exchange membrane CO_(2)electrolysis.
基金Project supported by the National Natural Science Foundation of China(Nos.31470092 and 31501459)the Natural Science Youth Foundation of Jiangsu Province(No.BK20130380)China
文摘（R）-2-hydroxy-3-phenylpropionic acid （PIP,） is an ideal antimicrobial compound with broad-spectrum activity against a wide range of Gram-positive bacteria, some Gram-negative bacteria, and fungi. We studied the bioconversion of phenylpyruvate （PPA） to PLA using whole recombinant Escherichia coli cells in a series of buffer/organic solvent systems. Octane was found to be the best organic solvent. The optimum volume ratio of the water phase to the n-octane phase, conversion temperature, substrate concentration, and cell concentration were 6：4, 40 ℃, 12.5 g/L, and 30 g/L wet cells, respectively. Under the optimized conditions, the average PLA productivity in the aqueous/ n-octane system was 30.69% higher than that in the aqueous system, and 32.31 g/L PLA was obtained with the use of a stirred reactor （2-L scale）. Taken together, our findings indicated that PLA biosynthesis was more efficient in an aqueous/n-octane biphasic system than in a monophasic aqueous system. The proposed biphasic system is an effective strategy for enhancing PLA yield and the biosynthesis of its analogues.
基金the support from National Key R&D Program of China (2021YFC2103704)the National Natural Science Foundation of China (22222808)+4 种基金the Natural Science Foundation of Shandong Province (ZR2023QB152)the Youth Innovation Team Plan of Shandong Province (2022KJ270)the China National Postdoctoral Program for Innovative Talents (BX20240251)the Aeronautical Science Foundation of China (2023Z073048003)the Haihe Laboratory of Sustainable Chemical Transformations。
文摘Photoinduced[2+2]cycloaddition of biomass-derived cycloolefin is a promising approach to synthesize high-energy bio-fuels,however,the conversion efficiency and selectivity are still low.Herein,we provide an acid-promoted photocycloaddition approach to synthesize a new kind of spiral fuel from biomass-derived cyclohexanone (CHOE) and camphene (CPE).BrΦnsted acids show higher catalytic activity than Lewis acids,and acetic acid (HOAc) possesses the best catalytic performance,with CHOE conversion up to 99.1%.Meanwhile,the HOAc-catalytic effect has been confirmed for[2+2]photocycloaddition of other biomass-derived ketenes and olefins.The catalytic mechanism and dynamics have been investigated,and show that HOAc can bond with C=O groups of CHOE to form H–CHOE complex,which leads to higher light adsorption and longer triplet lifetime.Meanwhile,H–CHOE complex reduces the energy gap between CHOE LUMO and CPE HOMO,shortens the distance of ring-forming atoms,and then decreases the energy barrier (from 103.3 kcal mol^(-1)to 95.8 kcal mol^(-1)) of rate-limiting step.After hydrodeoxygenation,the targeted bio-spiral fuel shows high density of 0.992 g cm^(-3),high neat heat of combustion of 41.89 MJ L^(-1),low kinetic viscosity of 5.69 mm^(2)s^(-1)at 20℃,which is very promising to serve as high-performance aerospace fuel.
基金supported by the National Natural Science Foundation of China,Nos.32371070 (to JT),31761163005 (to JT),32100824 (to QX)the Shenzhen Science and Technology Program,Nos.RCBS20210609104606024 (to QX),JCY20210324101813035 (to DL)+4 种基金the Guangdong Provincial Key S&T Program,No.2018B030336001 (to JT)the Key Basic Research Program of Shenzhen Science and Technology Innovation Commission,Nos.JCYJ20200109115405930 (to JT),JCYJ20220818101615033 (to DL),JCYJ20210324115811031 (to QX),JCYJ20200109150717745 (to QX)Shenzhen Key Laboratory of Neuroimmunomodulation for Neurological Diseases,No.ZDSYS20220304163558001 (to JT)Guangdong Provincial Key Laboratory of Brain Connectome and Behavior,No.2023B1212060055 (to JT)the China Postdoctoral Science Foundation,No.2021M693298 (to QX)。
文摘The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders.
基金Project supported by the Natural Science Foundation Innovation Group Project of Hubei Province(2023AFA044)the National Natural Science Foundation of China(52222405)+1 种基金the Science and Technology Research Project of Education Department of Hubei Province(Q20221505)the China Postdoctoral Science(2023M731041)。
文摘In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation recovery of bastnaesites can be achieved more than 90%when the aeration rate is 40 mL/min,the rotational speed is 200 r/min,the H205 dosage is 120 mg/L,and the pulp pH ranges from 7 to 9.The action mechanism of H205 on the surface of bastnaesite was studied by simultaneous thermogravimetry and differential scanning calorimetry(TG-DSC),Zeta potential measurements,Fourier transform-infrared spectra(FT-IR)and X-ray photoelectron spectroscopy(XPS).These analysis results show that under suitable flotation conditions,H205 has an obvious adsorption phenomenon on the surface of bastnaesite.The adsorption involves electrostatic interactions and chemical interactions,namely H205 has a strong collecting ability of bastnaesite due to the synergism of electrostatic adsorption and chemical adsorption.This study systematically reveals the flotation behavior and adsorption mechanism of H205 on the surface of bastnaesite,and provides useful theoretical guidance for efficient flotation separation of bastnaesite.
基金supported by the National Key Research and Development Program of China for Young Scientists(Grant No.2023YFB4104100)the National Natural Science Foundation of China(Grant 52176057)+3 种基金the National Key Research and Development Program of China(Grant No.2023YFB4104201)supported by the Unveiling and Commanding Foundation of Liaoning Province(Grant 2023JH1/10400003)the Shenzhen Science and Technology Program(No.JCYJ20220818095605012)supported by the Young Changjiang Scholars programme of China。
文摘Carbon dioxide(CO_(2))marine sequestration by hydrate method is considered as one of the options to effectively achieve carbon reduction.However,the slow rate of hydrate formation becomes a major limiting factor.In view of the gas-water mass transfer problem which is the main obstacle,this paper explored the amphiphilic amino acids to promote the formation of CO_(2)hydrate and used low-field nuclear magnetic resonance(LNMR)to conduct an innovative study on its kinetics and spatiotemporal distribution.By comparing the promotion performance of L-methionine(L-met),L-cysteine(L-cys),and L-valine(L-val),the comprehensive kinetic promotion ability of L-met was the highest,reducing the induction time by 60.0%,achieving the maximum water conversion of about 57.0%within only 1 h,and reaching a final CO_(2)storage efficiency of 84.6%.LNMR results showed that hydrates were preferentially formed in large and medium pores in the reservoir region.Interestingly,we found that the combined effect of hydrophilic groups and the hydrophobic side chain of L-met not only promoted the rearrangement of water molecules and provided more nucleation sites,but also created a localized CO_(2)supersaturated environment and facilitated gas-water redistribution.Meanwhile,L-met promoted the formation of a hydrate porous structure to ensure the continuous formation of hydrates.This study innovatively explored CO_(2)hydrate formation behavior in amphiphilic amino acids and laid a theoretical foundation for the realization of CO_(2)marine sequestration by hydrate method.
基金supported by the Project funded by the Natural Science Foundation of Hainan Province(Grant No.322QN248)the National Natural Science Foundation of China(Grant Nos.32401488,32060409,32371782 and 32460358)+3 种基金the Innovational Fund for Scientific and Technological Personnel of Hainan Province(Grant No.KJRC 2023C21)the Hainan High-level Talents Project(Grant No.321RC475)Collaborative Innovation Center Project of Nanfan and High-Efficiency Tropical Agriculture in Hainan University(XTCX2022NYB08)Collaborative Innovation Center Project of Ecological Civilization in Hainan University(XTCX2022STC10).
文摘Improving salt tolerance and mitigating senescence in the presence of high salinity are crucial for sustaining agricultural productivity.Previous research has demonstrated that hydrogen peroxide(H_(2)O_(2)),specifically H_(2)O_(2)derived from roots and mediated by the respiratory burst oxidase homolog(NADPH),plays a significant role in regulating ion and plant hormone homeostasis in glycophytic plants,such as Arabidopsis.However,the extent to which root-derived H_(2)O_(2)fulfils similar functions in halophytic plants remains uncertain.Therefore,our study aimed to explore the potential contribution of root-sourced H_(2)O_(2)in delaying leaf senescence induced by high salinity,utilizing seashore paspalum as a model halophytic plant.The application of the NADPH-oxidase inhibitor DPI,coupled with a series of leaf senescence analyses,we revealed that root-derived H_(2)O_(2)significantly retards salt-induced leaf senescence.Furthermore,through the application of hormone analysis,lipidomics,ionomics,Non-invasive Micro-test Technology(NMT),and transcriptomics,we established that NADPH-dependent H_(2)O_(2)induced by salt stress in the roots was indispensable for maintaining the balance of the aging hormone,jasmonic acid(JA),and sodium ion homeostasis within this halophytic plant.Finally,by utilizing AtrbohD Arabidopsis mutants and virus-induced gene silencing(VIGs)in Paspalum vaginatum,we demonstrated the pivotal role played by root-sourced H_(2)O_(2)in upholding JA homeostasis and regulating JA-triggered leaf senescence in P.vaginatum.This study offers novel insights into the mechanisms that govern plant leaf senescence and its response to salinity-induced stress.
基金supported by the Swedish Energy Agency(P47500-1)the National Key R&D Program of China(2020YFA0710200)+2 种基金the National Natural Science Foundation of China(22378401 and U22A20416)the financial support from STINT(CH2019-8287)financial support from the European Union and Swedish Energy Agency(P2020-90066).
文摘The catalytic oxidation of HMF involves a cascading reaction with multiple intermediate products,making it crucial to enhance the oriented adsorption capacity of specific functional groups for accelerating the entire process.To achieve the efficient selective oxidation of HMF to FDCA,a series of NiCo_(2)O_(4)catalysts with different morphologies,such as flaky,echinoids,pompon and corolla,were prepared and characterized by XRD,SEM,TEM,BET,XPS,and FTIR.Among the four catalysts,flaky NiCo_(2)O_(4)exhibited the most excellent catalytic activity and stability,with a FDCA yield of 60.1%within 12 h at 80℃without alkali participation.The excellent performance of flaky NiCo_(2)O_(4)catalyst is attributed to the oxygen vacancies and acid sites generated by the exposed(400)facets.The oxygen vacancies and acid sites on the catalyst surface can precisely adsorb-CHO and-CH_(2)-OH of HMF,respectively,and this synergistic effect promotes the efficient production of FDCA.This work is of great significance for fundamentally study the effect of micro-topography or crystal-plane reaction properties on surfaces.
基金supported by the National Natural Science Foundation of China(52301259 and 22208019)the Research Fund Program for Young Scholars of Beijing Institute of Technology。
文摘Electrochemical carbon dioxide reduction reaction(CO_(2)RR)converts CO_(2) into valuable chemicals by consuming renewable electricity at mild conditions,making it a promising approach to achieving carbon neutrality.However,the reaction of CO_(2) with hydroxide ions to form carbonates leads to low carbon utilization and energy efficiency in near-neutral or alkaline CO_(2)RR.The high concentration of protons in acidic media can effectively mitigate carbonate formation and deposition,thereby significantly minimizing carbon loss and energy consumption.Unfortunately,hydrogen evolution reaction(HER)is more kinetically favorable than CO_(2)RR in acidic media.Herein,we comprehensively overview recent progress in acidic CO_(2)RR and propose two strategies derived from the competing reaction pathways of HER and CO_(2)RR:one focuses on regulating the H+mass transport,while the other aims to modulate the intrinsic kinetic activity of CO_(2)RR.The two strategies are designed to compete for the limited active sites on the catalyst surface,inhibit side reactions,and enhance the activity and selectivity of CO_(2)RR.The representative approaches include modulating the interface electric field,constructing a local alkaline environment,and regulating competing adsorption sites.Finally,we also review the technical challenges and future perspectives of acidic CO_(2)RR coupled with membrane electrode assemblies(MEAs).
基金the Alliance Project of Shanghai City in China(LM201641)。
文摘Two different Mn-Ce-O_(x)/TiO_(2) catalysts were prepared by ordinary impregnation(denoted as MCT) and citric acid assisted impregnation(denoted as MCT-CA) methods,respectively.Excellent NOxremoval is achieved over MCT-CA for selective catalytic reduction with NH3(NH_(3)-SCR),and 100% NOxconversion is obtained at 125℃ under weight hour space velocity(WHSV) of 80000 mL/(gcat·h).Particularly,100% NOxis converted on MCT-CA in the presence of 10 vol% H2O at 175℃.As H2O and SO2coexist in the reaction system for 9 h,NO_(x) conversion can still be maintained>90%,much higher than that(22%) of MCT.A series of characterization results indicates that MCT-CA exhibits a larger BET specific surface area,pore volume,and pore size,which enhances the dispersion of Mn and Ce oxides and promotes the rapid adsorption of reactants and desorption of products.Additionally,MCT-CA possesses more Mn^(4+),Ce^(3+),chemisorbed oxygen species,and stronger reducibility,facilitating the co nversion of NO to NO_(2).Specially,the amount of active NH_(3) species and active nitrate species on MCT-CA is much more than that over MCT,The combined effect of the aforementioned factors devotes to the excellent low-temperature SCR performance and tolerance to H2O/SO2over MCT-CA.
