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HPLC Fingerprint Combined with Chemometrics and Network Pharmacology for Q-Markers Prediction Analysis of Saposhnikovia divaricata

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Journal of Analysis and Testing 2024年第1期8卷 83-94页

作者： Renguo Zhang Xinjian Liu Tong Wang Jie Yu Mengyuan Wang Jianmin Sun Xueling Yu Na Niu Ligang Chen College of Chemistry Chemical Engineering and Resource UtilizationKey Laboratory of Forest Plant EcologyNortheast Forestry UniversityHarbin 150040China

Saposhnikovia divaricata(SD)has high medicinal and edible value,but relatively little research has been done on its qual-ity markers(Q-markers).To further clarify the Q-markers of SD with their corresponding pharmacodynamic *** this experiment,14 batches of SD were identified and screened for Q-marker candidate components using a combination of HPLC fingerprint with similarity analysis,principal component analysis,hierarchical cluster analysis,and partial least squares discriminant ***,network pharmacology was used to predict Q-markers and core *** results showed that 5-O-methylvisammioside,cimifugin,and prim-O-glucosylcimifugin could be used as Q-markers of SD;while,MAPK1,MAPK3,PIK3CA,JUN,and MAPK8 were the core targets of SD for drug *** further evaluate the bind-ing efficiency of Q-markers,molecular docking of the main active ingredients of SD to the core targets was *** results showed that the compounds bind well to their targets,and binding energies were all less than-5 kcal/*** Q-markers obtained from the screening were closely related to the core target genes,which could achieve therapeutic effects by modulating the relevant signaling *** study offers a reference for the establishment of a set of quality control evaluation system for SD potential Q-markers prediction analysis,and lays the foundation for elucidating the mechanism of actionunderlying itspharmacodynamic substance.

关键词： Saposhnikovia divaricata Q-markers Fingerprint Chemometrics Network pharmacology Molecular docking

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin Dong-Sheng Ji Peng-Fei Xu State Key laboratory of applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key laboratory of chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

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Matrix Assisted Laser Desorption Ionization Time of Flight(MALDI-TOF)-Mass Spectrometry and^(13)C-NMR-Identified New Compounds in Paraberlinia bifoliolata(Ekop-Beli)Bark Tannins

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Journal of Renewable Materials 2024年第3期12卷 553-568页

作者： Liliane Nga Benoit Ndiwe Achille Bernard Biwolé Antonio Pizzi Jean Jalin Eyinga Biwole Joseph Zobo Mfomo laboratory of Forest Resources and Wood Valorization Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 1872DoualaCameroun laboratory of Mechanics Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 2701DoualaCameroun laboratory of Studies and research on Wood Material(LERMAB) University of LorraineNancyFrance

Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial *** discovery of new tannins is therefore *** aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica *** by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of *** are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic *** identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion *** information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the *** analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.

关键词： Tannin Paraberlinia bifoliolata Central African wood species MALDI-TOF/MS 13C NMR bark extracts thermomechanical behaviour wood-binder

Genome mining of sulfonated lanthipeptides reveals unique cyclic peptide sulfotransferases

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2773-2785页

作者： Meng Wang Wen-Wei Li Zhe Cao Jianong Sun Jiang Xiong Si-Qin Tao Tinghong Lv Kun Gao Shangwen Luo Shi-Hui Dong State Key laboratory of applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Although sulfonation plays crucial roles in various biological processes and is frequently utilized in medicinal chemistry to improve water solubility and chemical diversity of drug leads,it is rare and underexplored in ribosomally synthesized and post-translationally modified peptides(RiPPs).Biosynthesis of RiPPs typically entails modification of hydrophilic residues,which substantially increases their chemical stability and bioactivity,albeit at the expense of reducing water *** explore sulfonated RiPPs that may have improved solubility,we conducted co-occurrence analysis of RiPP class-defining enzymes and sulfotransferase(ST),and discovered two distinctive biosynthetic gene clusters(BGCs)encoding both lanthipeptide synthetase(LanM)and *** expressing these BGCs,we characterized the structures of novel sulfonated lanthipeptides and determined the catalytic details of LanM and *** demonstrate that SslST-catalyzed sulfonation is leader-independent but relies on the presence of A ring formed by *** LanM and ST are promiscuous towards residues in the A ring,but ST displays strict regioselectivity toward *** recognition of cyclic peptide by ST was further *** evaluation underscores the significance of the ST-catalyzed *** study sets up the starting point to engineering the novel lanthipeptide STs as biocatalysts for hydrophobic lanthipeptides improvement.

关键词： Lanthipeptides Sulfotransferases Sulfonation Biosynthesis Genome mining

Differential response of radial growth and δ^(13)C in Qinghai spruce(Picea crassifolia) to climate change on the southern and northern slopes of the Qilian Mountains in Northwest China

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Journal of Forestry research 2024年第3期35卷 205-218页

作者： Li Qin Huaming Shang Weiping Liu Yuting Fan Kexiang Liu Tongwen Zhang Ruibo Zhang Key laboratory of Tree-Ring Physical and chemical research(CMA)/Xinjiang Key laboratory of Tree-Ring ecology Institute of Desert MeteorologyChina Meteorological AdministrationUrimqi 830002People's Republicof China Xinjiang Meteorological Information Center Urimqi 830002People's Republic of China

Tree radial growth can have significantly differ-ent responses to climate change depending on the *** elucidate the effects of climate on radial growth and stable carbon isotope(δ^(13)C)fractionation of Qing-hai spruce(Picea crassifolia),a widely distributed native conifer in northwestern China in different environments,we developed chronologies for tree-ring widths and δ^(13)C in trees on the southern and northern slopes of the Qilian Mountains,and analysed the relationship between these tree-ring variables and major climatic ***-ring widths were strongly influenced by climatic factors early in the growing season,and the radial growth in trees on the northern slopes was more sensitive to climate than in trees on the ***-ring δ^(13)C was more sensitive to climate than radial growth.δ^(13)C fractionation was mainly influenced by summer temperature and precipitation early in the growing *** conductance more strongly limited stable carbon isotope fractionation in tree rings than photosynthetic rate *** response between tree rings and climate in mountains gradually weakened as climate *** in radial growth and stable carbon isotope fractionation of *** in response to climate in the Qilian Mountains may be further complicated by continued climate change.

关键词： Tree rings Qinghai spruce(Picea crassifolia Kom.) Stable carbon isotope(δ^(13)C) Qilian Mountains:Climate change

Cu single atoms embedded on hollow g-C_(3)N_(4)nanospheres with enhanced charge transfer and separation for efficient photocatalysis

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Chinese chemical Letters 2024年第2期35卷 455-459页

作者： Linlin Zhang Jianjun Liao Yakun Li Wei Sun Chengjun Ge Key laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province School of Ecology and EnvironmentHainan UniversityHaikou 570228China Shandong Ocean chemical Industry Scientific research Institute Weifang 262737China

Establishing an effective charge transfer mechanism in carbon nitride(g-C_(3)N_(4))to enhance its photocatalytic activity remains a limiting ***,the combination design of a single Cu atom with hollow g-C_(3)N_(4)nanospheres(Cu-N_(3)structure)has been proven to offer significant opportunities for this crucial ***,this structure endows two pathways for charge transfer in the reaction,namely,the N atoms in the three-dimensional planar structure are only bonded with a single Cu atom,and charge transfer occurs between the plane and the layered structure due to the bending of the interlayered g-C_(3)N_(4)hollow ***,Cu-N_(3)and hollow nanosphere structures have been certified to greatly enhance the efficiency of photogenerated carrier separation and transfer between the layers and planes by ultrafast spectral *** a result,this catalyst possesses unparalleled photocatalytic ***,the hydrogen production rate up to 2040μmol h^(−1) g^(−1),which is 51 times that of pure C_(3)N_(4)under visible light *** photocatalytic degradation performance of tetracycline and oxidation performance of benzene is also expressed,with a degradation rate of 100%,a conversion of 97.3%and a selectivity of 99.9%.This work focuses on the structure-activity relationship to provide the possibilities for the development of potential photocatalytic materials.

关键词： g-C_(3)N_(4) Cu single atom Hollow nanospheres Charge transfer pathways Photocatalytic hydrogen production

Total-factor energy efficiency of ten major global energy-consuming countries

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Journal of Environmental Sciences 2024年第3期137卷 41-52页

作者： Xuan Wang Yonglong Lu Chunci Chen Xiaojie Yi Haotian Cui State Key laboratory of Urban and Regional ecology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key laboratory of Marine Environmental Science and Key laboratory of the Ministry of Education for Coastal Wetland Ecosystems College of the Environment and EcologyXiamen UniversityFujian 361102China University of Chinese Academy of Sciences Beijing 100049China

Improving energy efficiency is regarded as a key path to tackling global warming and achieving the Sustainable Development Goals(SDGs).In 2020,the energy consumption of the world's ten major energy-consuming countries accounted for 66.8%of the global *** paper applied data envelopment analysis(DEA)to calculate these ten major energyconsuming countries'total-factor energy efficiency(TFEE)at national and sectoral levels from 2001-2020,and explored the infuencing factors of total-factor energy efficiency with the Tobit regression *** results showed significant difference in the ten countries'energy *** United States and Germany topped the list for total-factor energy efficiency,while China and India were at the ***,the energy efficiency of the industrial subsector has increased significantly over the past two decades,while that of the other subsectors has been relatively *** industrial structure upgrading,per capita GDP,energy consumption structure,and foreign direct investment had significant impacts on energy efficiency with national *** consumption structure and GDP per capita were determinative factors of energy efficiency.

关键词： Total-factor energy efficiency SBM-UN model Major energy-consuming country Carbon emission reduction

Highly selective adsorption of rhenium by amyloid-like protein material

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Science China(Technological Sciences) 2024年第5期67卷 1417-1430页

作者： MUHAMMAD Arif YANG QingMin KANWAL Aisha ZHAO Jian NAWAZ Mohsan REN Hao YANG Peng Key laboratory of applied Surface and Colloid Chemistry Ministry of Education Xi’an Key laboratory of Polymeric Soft Matter International Joint Research Center on Functional Fiber and Soft Smart TextileSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an710119China School of Chemistry and chemical Engineering Northwestern Polytechnical UniversityXi’an710072China

Rhenium separation from molybdenum in molybdenite minerals and waste leachate has become an emerging *** this challenge,we prepared a set of protein-based alkylamine/alkylammonium salts complexes as extractants for selective uptake of rhenium from molybdenum,where the protein component turned into the insoluble amyloid-like structure when its internal disulfide bonds were reduced,namely phase-transition *** them,the phase-transited lysozyme and methyletrioctyleammonium chloride complex(PTL-N263)exhibited the most efficient adsorption at the alkaline condition for the electrostatic interaction between negatively charged metal ions with positively charged center(R_(4)N^(+))in N263,where negatively charged protein residues hindered the ion exchange of Cl^(-)in N263 for larger size Mo species(Mo_(7)O_(24)^(6-))than smaller size Re species(ReO^(4-)).The adsorption follows the Freundlich model and pseudo-second-order kinetics,which exhibits toplevel adsorption performance with a maximum adsorption capacity of 124 mg/g and a separation factor(β_(Re/Mo))of 2.78×10^(3)for *** adsorption capacity per unit area(57.2 mg/(g m^(2)))is 1.6–41 times higher than previously reported adsorbents,and the cost for adsorbing 1 g of Re(VII)is$1.07,indicating its industrial *** adsorption strategy can be applied to separating Re from Mo in binary solutions and industrial wastewater with other competing ions.

关键词： amyloid phase-transited lysozyme selective adsorption rhenium waste leachate solution

Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yangsiding Wang Da Yang German Vargas G. Guangyou Hao Jennifer S.Powers Yan Ke Qin Wang Yunbing Zhang Jiaolin Zhang CAS Key laboratory of Tropical Forest ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China School of Biological Sciences University of UtahSalt Lake CityUT 84112USA CAS Key laboratory of Forest ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of ecology Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insight into divergence in ecophysiological strategies among plant functional groups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and evergreen woody species contributes to physiological trait tradeoffs in a dry-hot valley savanna. We investigated 11 photosynthetic, morphological and hydraulic traits of 24 species including 8 deciduous, 10 semi-deciduous and 6 evergreen species. Deciduous species were grouped in the fast and avoidance side associated with high values of maximum photosynthetic rates,stomatal conductance and leaf size, while evergreen species were grouped in the slow and tolerance side associated with high photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turgor loss point and water potential causing 50% loss of stem hydraulic conductance. Semideciduous species generally had intermediate trait values and represented different physiological characteristics when compared to deciduous and evergreen species. The physiological trait tradeoffs showed a close linkage to the differentiation of these three leaf habits. Our findings clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strategies among diverse savanna plants, suggesting a syndrome in multiple ecophysiology strategies across different leaf habits.

关键词： Dry-hot habitat Gas exchange Hydraulics Phenology Tolerance Valley savanna