Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redo...Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redox chemistry through elaborate surface OO–Ru–OH and bulk Ru–O–Ni/Fe coordination moieties within single-atom Ru-decorated defective NiFe LDH nanosheets(Ru@d-NiFe LDH)in conjunction with strong metal-support interactions(SMSI).Rigorous spectroscopic characterization and theoretical calculations indicate that single-atom Ru can delocalize the O 2p electrons on the surface and optimize d-electron configurations of metal atoms in bulk through SMSI.The^(18)O isotope labeling experiment based on operando differential electrochemical mass spectrometry(DEMS),chemical probe experiments,and theoretical calculations confirm the encouraged surface lattice oxygen,stabilized bulk lattice oxygen,and enhanced adsorption of oxygen-containing intermediates for bulk metals in Ru@d-NiFe LDH,leading to asymmetric redox chemistry for OER.The Ru@d-NiFe LDH electrocatalyst exhibits exceptional performance with an overpotential of 230 mV to achieve 10 mA cm^(−2)and maintains high robustness under industrial current density.This approach for achieving asymmetric redox chemistry through SMSI presents a new avenue for developing high-performance electrocatalysts and instills confidence in its industrial applicability.展开更多
Ginsenoside Rb3(G-Rb3)is one of the primary active compounds isolated from Panax ginseng Meyer,which belongs to protopanaxadiol ginsenosides(PPD).Based on the structure-activity relationship(SAR)of ginsenosides,the pe...Ginsenoside Rb3(G-Rb3)is one of the primary active compounds isolated from Panax ginseng Meyer,which belongs to protopanaxadiol ginsenosides(PPD).Based on the structure-activity relationship(SAR)of ginsenosides,the pentose structure of G-Rb3 limited itself to possess more pharmacological activity to a certain extent.However,pharmacokinetics show that G-Rb3 is processed through deglycosylation in the intestinal tract and converted into more active rare saponins,such as Compound K,F2,etc.A series of studies focused on neuroprotection and the cardiovascular system demonstrating its therapeutic potentials,which was achieved by diminishing oxidative stress and apoptosis.Therefore,more systematic and in-depth studies are needed to complete the pharmaceutical value and to promote its clinical applications.This article highlights the multiple pharmacological effects and mechanisms of G-Rb3 and prospects for its development.展开更多
Medicago polymorpha L(MPL),a high-protein legume from southern China,is difficult to ferment and preserve due to its high moisture content and buffering capacity.Effects of three different wilting times(4,8,and 12 h)a...Medicago polymorpha L(MPL),a high-protein legume from southern China,is difficult to ferment and preserve due to its high moisture content and buffering capacity.Effects of three different wilting times(4,8,and 12 h)and chopping lengths(2,4,and 6 cm)on the fermentation ripening rate,chemical composition,microbial communities,and functional properties of MPL during anaerobic fermentation in small packages were evaluated.The results indicate that reducing the wilting time and chopping length increased the lactic acid content and decreased the pH during fermentation.Additionally,the content of Lactobacillus brevis was positively correlated with free amino acids.Shortening the chopping length increased the abundance of Levilactobacillus brevis(7.913%vs.26.100%)and Ligilactobacillus animalis(0.038%vs.0.163%).Under shorter chopping lengths,extending the wilting time increased the abundance of Methylobacterium adhaesivum and Methylorubrum extorquens(0.121%vs.1.292%)and decreased the content of non-protein nitrogen.Bacterial community analysis showed that Lactobacillus and Weissella were the core microbiota after fermentation,with the former promoting the increase of organic acids,free amino acids,and flavor compounds.In conclusion,the high quality and rich flavor compounds of fermented MPL can be ensured by reducing the wilting time(4 h)and shortening the chopping length(2 cm).展开更多
基金supported by the Guangdong Basic and Applied Basic Research Foundation(2021B1515120072)the Natural Science Foundation of China(22279096 and T2241003)the Fundamental Research Funds for the Central Universities(WUT:2023IVA094).
文摘Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redox chemistry through elaborate surface OO–Ru–OH and bulk Ru–O–Ni/Fe coordination moieties within single-atom Ru-decorated defective NiFe LDH nanosheets(Ru@d-NiFe LDH)in conjunction with strong metal-support interactions(SMSI).Rigorous spectroscopic characterization and theoretical calculations indicate that single-atom Ru can delocalize the O 2p electrons on the surface and optimize d-electron configurations of metal atoms in bulk through SMSI.The^(18)O isotope labeling experiment based on operando differential electrochemical mass spectrometry(DEMS),chemical probe experiments,and theoretical calculations confirm the encouraged surface lattice oxygen,stabilized bulk lattice oxygen,and enhanced adsorption of oxygen-containing intermediates for bulk metals in Ru@d-NiFe LDH,leading to asymmetric redox chemistry for OER.The Ru@d-NiFe LDH electrocatalyst exhibits exceptional performance with an overpotential of 230 mV to achieve 10 mA cm^(−2)and maintains high robustness under industrial current density.This approach for achieving asymmetric redox chemistry through SMSI presents a new avenue for developing high-performance electrocatalysts and instills confidence in its industrial applicability.
基金This work was funded by the grant of Jilin Science&Technology Development Plan(No.20200301037RQ).
文摘Ginsenoside Rb3(G-Rb3)is one of the primary active compounds isolated from Panax ginseng Meyer,which belongs to protopanaxadiol ginsenosides(PPD).Based on the structure-activity relationship(SAR)of ginsenosides,the pentose structure of G-Rb3 limited itself to possess more pharmacological activity to a certain extent.However,pharmacokinetics show that G-Rb3 is processed through deglycosylation in the intestinal tract and converted into more active rare saponins,such as Compound K,F2,etc.A series of studies focused on neuroprotection and the cardiovascular system demonstrating its therapeutic potentials,which was achieved by diminishing oxidative stress and apoptosis.Therefore,more systematic and in-depth studies are needed to complete the pharmaceutical value and to promote its clinical applications.This article highlights the multiple pharmacological effects and mechanisms of G-Rb3 and prospects for its development.
基金supported by the National Key R&D Pro-gram of China(2021YFD1300300)Guizhou Provincial Science and Technology Project(BQW[2024]003)Guizhou University Doctoral Fund[grant numbers(2022)31].
文摘Medicago polymorpha L(MPL),a high-protein legume from southern China,is difficult to ferment and preserve due to its high moisture content and buffering capacity.Effects of three different wilting times(4,8,and 12 h)and chopping lengths(2,4,and 6 cm)on the fermentation ripening rate,chemical composition,microbial communities,and functional properties of MPL during anaerobic fermentation in small packages were evaluated.The results indicate that reducing the wilting time and chopping length increased the lactic acid content and decreased the pH during fermentation.Additionally,the content of Lactobacillus brevis was positively correlated with free amino acids.Shortening the chopping length increased the abundance of Levilactobacillus brevis(7.913%vs.26.100%)and Ligilactobacillus animalis(0.038%vs.0.163%).Under shorter chopping lengths,extending the wilting time increased the abundance of Methylobacterium adhaesivum and Methylorubrum extorquens(0.121%vs.1.292%)and decreased the content of non-protein nitrogen.Bacterial community analysis showed that Lactobacillus and Weissella were the core microbiota after fermentation,with the former promoting the increase of organic acids,free amino acids,and flavor compounds.In conclusion,the high quality and rich flavor compounds of fermented MPL can be ensured by reducing the wilting time(4 h)and shortening the chopping length(2 cm).
