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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang zhi-Li Zuo han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-jiang Hao Key Laboratory of Phytochemistry and natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Consuming fermented distillers＇ dried grains with solubles (DDGS) feed reveals a shift in the faecal microbiota of growing and fattening pigs using 454 pyrosequencing

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Journal of Integrative Agriculture 2017年第4期16卷 900-910页

作者： WANG Jin han ye ZHAO Jin-zhao zhou zhi-jiang FAN Huan School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P.R.China Tianjin Kuntai Environment & Energy Science and Technology Development Co. Ltd. Tianjin 300191 P.R. China Tianjin Animal Science and Veterinary Research Institute Tianjin 300381 P.R.China Key Laboratory of Systems Bioengineering Ministry of Education Tianjin 300072 P.R China

The objective of this study was to investigate pig fed by Bacillus coagulans-fermented distillers＇ dried grains with solubles （DDGS） on the faecal microbial composition and diversity using 454 pyrosequencing. Healthy crossbred （Durocx Yorkshirex Landrace） growing and fattening pigs （n=48）, with an average initial body weight of 65 kg, were divided into two groups （24 replicates per group; four pens per group; six pigs per pen）, and given either DDGS feed as the control, or B. coagulans-fermented DDGS feed as the treatment. Faecal samples were collected on day 0, 7, 14, 21, and 28. Dna was extracted, and the V3-V6 region of the 16S rRna gene was amplified. The fermented DDGS feed affected the relative abundance of bacteria populations at the phylum, genus, and species levels. At the genus level, the consumption of fermented DDGS feed led to higher relative abundances of faecal Prevotella, Lactobacillus, Clostridium, Bifidobacterium, Roseburia, and Bacillus, and lower relative abundances of faecal Escherichia, Ruminococcus, Dialister, unclassified Lachnospiraceae, unclassified Ruminococcaceae, and unclassified Enterobacteriaceae than in the control. At the species level, the consumption of fermented DDGS feed led to higher relative abundances of faecal Prevotella sp., Lactobacillus johnsonii, Lactobacillus fermentum, Lactobacillus mucosae, Lactobacillus reuteri, Clostridium butyricum, Bifidobacterium sp., and Roseburia sp., and lower relative abundances of faecal Prevotella copri, Escherichia coil, Ruminococcus gnavus, Ruminococcus flavefaciens, and Dialister sp. than in the control. Principal coordinates analysis indicated a distinct separation in the faecal microbial communities of pigs that were fed the fermented and unfermented DDGS feed. Fermented DDGS feed significantly increased the average daily gain （ADG） of pigs, and significantly decreased the average daily feed intake （ADFI） of feed and feed/gain （F/G）. Thus, our results demonstrate a beneficial shift in t

关键词： faecal microbiota growing and fattening pigs pyrosequencing fermented DDGS feed

Zwitterionic hyaluronic acid derivatives for co-delivery of both chemotherapeutic and nucleic acid drugs in breast cancer treatment

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nano Research 2025年第1期18卷 607-617页

作者： Ruo-Lin jiang Hui-na liu Yu-Fan Yang zhi-Cheng Zhang Qi Dai Xiao-Yan Bao Lin-Jie Wu Ya-Xin Qin Xin Tan Xiao-Yan Sun Xu-Fang Ying zhi-Qing Ben Min han Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionThe Second Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310058China hangzhou Institute of Innovative Medicine Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China national Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China Polytechnic institute Zhejiang UniversityHangzhou 310015China

Traditionally,hyaluronic acid has been widely used for drug delivery,but the current application bottleneck is that hyaluronic acid is hydrophilic and electronegative,which makes it difficult to carry hydrophobic drugs and small interfering Rna(siRna)with the same *** on previous studies,we designed and synthesized hyaluronic acid nanocarriers HA-spermine/N,N,N-trimethylcystamine/DOX-TPP(HSTD)for loading siRna to overcome the problem of siRna release caused by strong electrostatic ***,N,N,Ntrimethylcystamine in the carrier can be degraded by intracellular glutathione to completely and rapidly release siRna,thus promoting ***,when codelivered with the chemotherapy drug doxorubicin(DOX),this novel nanocarrier showed promising synergy in inhibiting tumor growth.

关键词： zwitterionic hyaluronic acid N N N-trimethylcystamine small interfering Rna(siRna) doxorubicin

Dehydration-triggered structural phase transition-associated ferroelectricity in a hybrid perovskite-type crystal

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Chinese Chemical Letters 2024年第10期35卷 461-464页

作者： zhi-Yuan Yue Hua-Kai Li na Wang shan-shan liu Le-Ping Miao Heng-Yun ye Chao Shi Chaotic Matter Science Research Center Jiangxi University of Science and TechnologyGanzhou 341000China

Since the appearance of Rochelle salt,ferroelectrics have received extensive attention from researchers due to they are playing an important role in sensors,memories,mechanical actuation,and so *** recent years,with the rapid development of molecular ferroelectrics,high-performance molecular ferroelectrics have become effective complement to inorganic ***,compared with inorganic ferroelectrics,the family of molecular ferroelectrics is relatively scarce,and exploring highperformance ferroelectric materials through new synthesis strategies has become the trend of molecular ***,we successfully transformed non-polar material 1(2-H_(2)PCA)_(2)(H_(2)O)CdCl_(6)(2-H_(2)PCA=2-picolylamine cation)into polar material 2(2-H_(2)PCA)2CdCl_(6)by single-crystal to single-crystal transformation(SCSCT).Meanwhile,2 exhibits clear ferroelectricity with a high-temperature Tc of 378 K,a Ps of 1.18μC/cm^(2)at 300 *** work not only realizes the purpose of synthesizing ferroelectrics by forming polar structures by SCSCT,but also realizes the reversibility of SCSCT,which provides ideas for the construction and exploration of new molecular ferroelectrics.

关键词： Hybrid perovskite Ferroelectric materials Single-crystal to single-crystal transformation Phase transition Stimulus-structure-response

Deciphering the molecular mechanisms of Simiaowan in the treatment of hyperuricemia: in vivo and in silico approaches

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Traditional Medicine Research 2025年第2期10卷 37-54页

作者： Yong-Chang Zeng Jun-Hong Wu Dan-Dan Xu Kang He Chang-Qing liu Li-Fei Song Zheng-zhi Wu Qian-Qian jiang Shao-Yu Liang Department of Neurology The First Affiliated Hospital of Shenzhen UniversityShenzhen 518020China Pharmaceutical Department The Affiliated TCM Hospital of Guangzhou Medical UniversityGuangzhou 510000China School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China Guangzhou Zeli Medical Technology Co. Ltd.Guangzhou 510700China

Background:Simiaowan(SMW),a well-known traditional Chinese medicine,has been employed to treat hyperuricemia(HUA)and gout for ***,the bioactive components and underlying mechanisms have not been *** objective of this study was to identify the active components and potential mechanisms of SMW by integrating pharmacological experimentation,serum pharmacochemistry,network pharmacology and molecular ***:HUA rats modelling by high-fat/high-sugar diet and potassium oxonate/adenine oral administration were used to evaluate the pharmacodynamic effects of ***-Q-Exactive-MS/MS was employed to detect the bioactive components present in SMW-containing *** pharmacology and molecular docking were utilized to elucidate the potential targets and underlying ***:SMW effectively ameliorated HUA rats via the inhibition of uric acid(UA)production,promotion of UA excretion,improvement of lipid and glucose metabolic abnormalities,antioxidant,anti-inflammatory and anti-insulin resistance effects.A total of 73 compounds detected in SMW-containing serum were identified as potential active components,with alkaloids,flavonoids,organic acids,and terpenoids emerging as the primary active *** 203 corresponding targets were obtained as SMW anti-HUA/gout targets,which mainly participated in apoptosis,insulin resistance,TNF,PI3K-Akt,HIF-1,NF-κB,MAPK,IL-17 and TLR signaling *** docking indicated that active compounds(***,phellodendrine,quercetin,formononetin,ferulic acid)had superior binding abilities to the key targets(*** carrier family 22 member 12(URAT1),solute carrier family 22 member 6(OAT1),ATP-binding cassette sub-family G member 2(ABCG2),solute carrier family 2,facilitated glucose transporter member 9(GLUT9),xanthine dehydrogenase/oxidase(XDH),transcription factor p65(RELA),toll-like receptor 4(TLR4),prostaglandin G/H synthase 2(PTGS2),caspase-3(CASP3),insulin(INS)).Conclusion:S

关键词： hyperuricemia network pharmacology serum pharmacochemistry Simiaowan UPLC-Q-Exactive-MS/MS

Recent advances of hydrogen production through particulate semiconductor photocatalytic overall water splitting

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Frontiers in Energy 2022年第1期16卷 49-63页

作者： zhi jiang Zhen ye Wenfeng shanGGUAN Research Center for Combustion and Environment Technology Shanghai Jiao Tong UniversityShanghai 200240China

Solar energy-driven photocatalytic water splitting has been investigated for decades to produce clean and renewable green *** this paper,the cutting-edge research within the overall water splitting system is summarized from the one-step photocatalytic overall water splitting(POWS)system to the two-step system and the cocatalysts research in this *** addition,the photocatalytic reaction engineering study is also reviewed which is crucial for future *** mini-review provides a picture of survey of recent progress of relevant overall water splitting system,with particular attention paid to material system and mechanistic breakthroughs,and highlights the challenge and opportunity of the current system.

关键词： photocatalysis overall water splitting hydrogen

Simulation of hard–soft material interaction under impact loading employing the material point method

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Science China(Technological Sciences) 2015年第4期58卷 763-768页

作者： liu han Tao jiang shan CHEN Zhen GAN Yong ChanG Jian Zhong WANG Yan Hua TONG zhi Hui Laboratory of Energy & Environment and Computational Fluid Dynamics North University of China Department of Civil and Environmental Engineering University of Missouri School of Aeronautics and Astronautics Zhejiang University

Understanding the mechanisms of hard–soft material interaction under impact loading is important not only in the defense industry but also in daily ***,traditional mesh-based spatial discretization methods that are time consuming owing to the need for frequent re-meshing,such as the finite element method and finite difference method,can hardly handle large deformation involving failure evolution in a multi-phase interaction *** objective of this research is to develop a quasi-meshless particle method based on the material point method for the model-based simulation of the hard–soft material interaction *** demonstrate the proposed procedure,scenarios of a hard–soft material impact test are considered,where a force is applied to layers of materials and a hard bar with an initial velocity impacts a target with layers of different *** stress wave propagation and resulting failure evolution are simulated and compared with available *** research tasks are then discussed on the basis of the preliminary results.

关键词： material point method hard--soft materials impact quasi-meshless particle method

Improvement of mechanical properties and investigation of strengthening mechanisms on the Ti_(3)AlC_(2) ceramic with nanosized WC addition

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Journal of Advanced Ceramics 2024年第6期13卷 861-876页

作者： Yi Zhong Ying liu Qinkai jiang na Jin Zifeng Lin Jinwen ye School of Materials Science&Engineering Sichuan UniversityChengdu 610065China Yibin R&D Park Yibin Industrial Technology Research InstituteSichuan UniversityYibin 644005China

Ti_(3)AlC_(2) (TAC) has great potential for use as an ablation material in aerospace applications due to its great oxidation/ablation resistance, but its high-temperature strength and thermal shock resistance still have much room for simultaneous improvement under fast temperature variation conditions. Herein, we used Ti_(3)AlC_(2) and WC powders as raw materials and successfully fabricated textured (Ti,W)_(3)AlC_(2) ceramic with small amounts of TiC and Al_(2)O_(3), and room temperature mechanical properties such as flexural strength (1146±46.9 MPa), fracture toughness (11.78±0.44 MPa·m^(1/2)), and hardness (5.81±0.11 GPa) at 5 wt% WC addition were achieved. The high-temperature strength of the ceramic was significantly improved, and better thermal shock resistance from 298 to 1173 K was simultaneously acquired together with the regulation of the elastic modulus, thermal conductivity, and thermal expansion coefficient, providing (Ti,W)_(3)AlC_(2) with more possibilities for fast-temperature variation applications. Strengthening and toughening mechanisms were proposed. Scanning transmission electron microscopy high-angle annular dark-field imaging (STEM-HADDF) showed that W randomly replaced the Ti1 and Ti2 sites of Ti_(3)AlC_(2), providing a good reference for establishing crystal models, and further density functional theory (DFT) calculations based on these models indicated a higher fracture energy of (Ti,W)_(3)AlC_(2) along different crystal planes, providing superior resistance to transgranular fracture;a lower mismatch degree of (Ti,W)_(3)AlC_(2)/Al_(2)O_(3) resulted in stronger interface bonding, resulting in greater resistance to intergranular fracture as well as more balanced stress distributions at different interfaces.

关键词： mechanical properties solid solution MAX phase transmission electron microscopy(TEM) ceramic atomic structure

Dynamic Recrystallization Behavior of GCr15SiMn Bearing Steel during Hot Deformation

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Journal of Iron and Steel Research International 2014年第11期21卷 1042-1048页

作者： Dan ZhanG Ya-zheng liu Le-yu zhou Qiang han Bo jiang Zhong-zhi LI School of Material Science and Engineering University of Science and Technology Beijing Dongbei Special Steel Group Corporation Limited

The hot deformation behavior of GCr15SiMn steel was studied through high temperature compression tests on the Gleeble-1500 thermal-mechanical simulator. The initiation and evolution of dynamic recrystallization （DRX） were investigated with microstructural analysis and then the process variables were derived from flow curves. In the present deformation conditions, the curves of strain hardening exponent （n） and the true strain （e） at the deformation temperature of 1423 K and strain rates of 0.1, 1 and 10 s^-1 exhibit single peak and single valley. According to Zener-Hollomon and Ludwik equation, the experimental data have been regressed by using linear method. An expression of Z parameter and hot deformation equation of the tested steel were established. Moreover, the Q values of GCrlSSiMn and GCr15 steels were compared. In order to determine the recrystallization fraction under different con ditions, the volume fraction of DRX as a function of process variables, such as strain rate （ε）, temperature （T）, and strain （ε）, was established. Itwas found that the calculated results agreed with the mierostructure of the steel at any deformation conditions.

关键词： GCr15SiMn strain hardening exponent dynamic recrystallization critical strain kinetic model