TETRAHEDRON
·
2018
·
IF 2.377
Mengxuan Chen,Weiyun Chai,Rongyao Zhu,Tengfei Song,Zhizhen Zhang,Xiao-Yuan Lian
Secondary metabolites from marine-associated actinomycetes are important source for the discovery of novel bioactive compounds. In this study, an actinomycete Streptomyces sp. ZZ446 was isolated from coastal soils and different media were used to culture this isolated marine actinomycete. It has been found that this actinomycete in the liquid medium of 2216 E with sea salt produced five new compounds of streptopyrazinones A−D ( 1 – 4 ) and N -acetyl- l -isoleucine- l -leucinamide ( 5 ) as well as six known diketopiperazines ( 6 – 11 ) and one alkaloid ( 12 ). Structures of the new compounds were determined by extensive NMR analyses, HRESIMS data, electronic circular dichroism (ECD) calculation, chemical degradation , Marfey's method, and X-ray diffraction analysis. This type of streptopyrazinones A−D ( 1 – 4 ) is rarely found in the natural resources. New compounds 1 – 5 showed activity in inhibiting the growth of Candida albicans and methicillin-resistant Staphylococcus aureus .
研究领域:
微生物学
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药物化学
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天然产物研究
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高影响因子
CHEMISTRY OF MATERIALS
·
2026
·
IF 7.1
Shiyue Sun,Jie Zhu,Tingting Li,Shaolin Du,Yunzhe Ke,Chenfei Yang,Yajing Sun,Xiaotao Zhang,Shuaishuai Ding,Wenping Hu
The design of molecular magnets with programmable spin states at room temperature is challenging for quantum materials. Although organic charge transfer (CT) cocrystals offer a promising framework for tuning spin states through electronic coupling, the deliberate design of donor (D)-acceptor (A) pairs and based on orbital-regulation strategy to mediate effective magnetic interactions has remained unexplored. Here we prove that CT cocrystals provide a platform where metal orbital characteristics govern magnetic strength, while the ordered CT lattice mediates long-range exchange interactions to support collective magnetic ordering. We obtained C60-H2TPP, C60-CuTPP, C60-CoTPP with successively increasing ferromagnetism at 300 K. Through orbital-regulation strategy, the substitution of metal ion Cu2+ with Co2+ precisely reorients the unpaired electron orbital from an alignment parallel to the donor molecule plane to one that points directly toward the C60 molecule. This spatial orientation leads to a significant enhancement in saturation magnetization, revealing that the orbital orientation of the D and A molecules can systematically govern the ferromagnetic ground state in cocrystals. Our results support orbital-regulation strategy as an effective design principle for room-temperature molecular magnets, with implications for spintronic applications based on organic quantum materials.
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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2026
·
IF 6.7
Xurui Zhao,Xiufeng Wang,Yijie Sheng,Shuizhi Lin,Shuping Xu,Zhixiang Hu,Xueping Ling,Cuixue Chen,Mingfeng Cao,Haiyang Cui,Yinghua Lu
Phosphatidylserine (PS), a major brain phospholipid, supports the central nervous system’s health and may alleviate cognitive decline, including in Alzheimer’s disease. A key challenge in green enzymatic PS synthesis is the suppression of hydrolysis while enhancing PLD-catalyzed transphosphatidylation. Here, we developed a mechanism-guided engineering strategy for Streptomyces antibioticus phospholipase D (SaPLD). The substitution of W187I increased the PS yield to 58.3%, while V380W improved thermostability. Combining beneficial mutations generated SaPLD-R7 (W187I/V380W/G381A), which overcame the activity–stability trade-off and achieved up to 95.8% PS yield using the enzyme produced by 5 L scale fermentation. Molecular dynamics simulations showed that SaPLD-R7 enhanced substrate binding and catalysis by shortening the key active site distances and reducing local flexibility. Solvent contact and energy analyses further indicated improved stability. This work establishes a structure–mechanism–function framework for enhancing PLD transphosphatidylation and provides a robust enzymatic route for high-efficiency PS production as a valuable functional food ingredient.
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Catalysts
·
2026
·Vol. 16
·期 6
·552
·
IF 4.5
Chang-Li Xu,Xiao-Mei Wu,Bao-Di Ma,Yi Xu
The (3aS, 6aR)-lactone serves as the key chiral intermediate for the synthesis of d-biotin. A promising approach involves the asymmetric hydrolysis of meso-dimethyl ester catalyzed by an esterase to yield the (4S, 5R)-monomethyl ester, which is subsequently reduced and cyclized to afford (3aS, 6aR)-lactone. This study first optimized the fermentation medium and culture conditions for the recombinantE. colipET21a-EstSIT01 harboring theMicrobacteriumesterase gene, which exhibits high selectivity for the asymmetric synthesis of (4S, 5R)-monomethyl ester. Under optimal conditions (fermentation medium: glycerol 25 g/L, yeast extract 15 g/L, NaCl 10 g/L, MgSO4•7H2O 5 g/L; induction was initiated 2 h post-inoculation at 30 °C and pH 7.2), the enzyme activity increased 5.1-fold compared to the initial level, reaching 1072.7 U/L. Secondly, the reaction conditions for the whole-cell synthesis of (4S, 5R)-monomethyl ester catalyzed by EstSIT01 were optimized. The results indicated that organic solvents adversely affected enzyme stability, while high buffer salt concentration negatively impacted enzyme activity at elevated substrate concentrations. The optimal reaction strategy involved maintaining the pH of the aqueous reaction system at 7.5 by the controlled addition of aqueous ammonia to neutralize the (4S, 5R)-monomethyl ester produced during the reaction. Using 17.5 g/L cells and 200 mM substrate meso-dimethyl ester in deionized water, with the reaction pH mentioned at 7.5, complete conversion (100%) was achieved within 4 h at 30 °C. The space–time yield reached 441.6 g/L/d, exceeding the typical requirement for industrial biotransformation (>100 g/L/d), with 99.1% enantiomeric excess (ee) of (4S, 5R)-monomethyl ester. Finally, (4S, 5R)-monomethyl ester was reduced using sodium borohydride to synthesize (3aS, 6aR)-lactone with an ee value of 98.7%. The overall yield from meso-dimethyl ester to (3aS, 6aR)-lactone was 86.2%. These results demonstrate that this integrated chemo-enzymatic approach constitutes a greener method with promising potential for industrial application.
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Nature Communications
·
2025
·Vol. 16
·期 1
·1-9
·
IF 15.7
Zhou Yin,Yin Kun,Huang Yingying,Li Jiapei,Zhu Anquan,Lin Dewu,Gan Guoqiang,Zhang Jianfang,Liu Kai,Zhang Tian,Liu Kunlun,Luan Chuhao,Yang Huawei,Chen Hou,Guo Shaojun,Zhang Wenjun,Hong Guo
Charge overpotential for oxygen evolution reaction is a crucial parameter for the energy conversion efficiency of lithium-oxygen (Li-O 2 ) batteries. So far, the realization of low charge overpotential via catalyst design is a grand challenge in this field, which usually exceeds 0.25 V. Herein, we report an orbital reconstruction strategy to significantly decrease the charge overpotential to the low 0.11 V by employing PdCo nanosheet catalyst under a low-loading mass (0.3 mg/cm 2 ) and capacity (0.3 mAh/cm 2 ). Experimental and theoretical calculations demonstrate that the precise d-d orbital coupling ( d xz - d xz , d yz - d yz and d z 2 - d z 2 ) between the low-electronegativity Co and Pd leads to the reconstruction of Pd 4 d orbitals in PdCo nanosheets, thereby resulting in a downward shift of all the three active Pd 4 d orbitals ( d z 2 , d xz and d yz ) relative to that of Pd nanosheets. Furthermore, the highest energy level of the Pd 4 d z 2 orbital in PdCo is lower than the lowest energy levels of the Pd 4 d xz and 4 d yz orbitals in pure Pd, significantly decreasing the charge activation energy and achieving a highest energy conversion efficiency of 91%. This finding provides the orbital-level tuning into rational design of highly efficient electrocatalysts for Li-O 2 batteries.
研究领域:
材料科学
·
电化学
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ADVANCED MATERIALS
·
2025
·
IF 26.8
Guobin Yu,Xiaoya Liu,Weiyuan Huang,Shixin Wang,Jiqiang Zhan,Lu Ma,Hongpeng Li,Xiaojing Lin,Tongchao Liu,Khalil Amine,Hongsen Li
Rechargeable aluminum-sulfur batteries (Al-S) are emerging as a promising alternative energy storage system beyond lithium-ion batteries due to their high energy density, abundant material resources, and economic efficiency. However, their practical application remains challenged by sluggish conversion kinetics, polysulfide shuttling, and low sulfur cathode utilization. While extensive studies have focused on enhancing polysulfide adsorption through catalytic strategies, the roles of electronic structure in dictating catalytic performance remain underexplored. Here, this work unveils the critical effect of unpaired electronic structure on the catalytic performance of single atom ferromagnetic transition metals through a systematic evaluation of three typical atomically dispersed ferromagnetic single atoms—Fe, Co, and Ni—supported on porous carbon (denoted as PC-SAFAs). Comprehensive characterizations and density functional theory (DFT) calculations reveal that the PC-SAFe catalysts, exhibiting the highest spin polarization arising from unpaired electrons, demonstrate the strongest interactions with polysulfide, thereby facilitating rapid and reversible polysulfide conversion reactions. Consequently, Al-S batteries incorporating the optimized PC-SAFe cathode achieve an impressive specific capacity of 508.8 mAh g −1 at 1.0 A g −1 after 500 cycles, along with much improved rate capability. This work provides a deeper understanding of the role of electronic structure in catalytic chemistry, and offers new insights for developing high-performance Al-S batteries.
研究领域:
材料科学
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电化学
·
能源存储
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Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Xinying Su,Jintao Luo,Yu Wang,Jinghao Dong,Yu Tian
D -amino acids can inhibit the formation of biofilm without affecting bacterial growth, which is a new strategy to control membrane biofouling. This paper investigated the effects of D -tyrosine on the performance of membrane bioreactor (MBR) during short-term operation. The results showed that the critical flux of activated sludge in MBR increased with the existence of D -tyrosine. The removal efficiencies of wastewater were not affected by D -tyrosine. The fouling propensities of soluble microbial products (SMP) in both MBRs were almost the same. Extracellular polymeric substance (EPS) in D -tyrosine group exhibited weaker fouling propensity. Further research indicated that the addition of D -tyrosine did not have a significant impact on SMP. D -tyrosine lead to the reduction of EPS polysaccharides and the great fluctuation of EPS protein. Microbial community analysis demonstrated that the addition of D -tyrosine changed the microbial community structure in MBR, which might be one of the reasons for the change of EPS.
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FOOD CHEMISTRY
·
2023
·
IF 8.8
Maiquan Li,Mingzhi Zhu,Wei Quan,Weisu Huang,Xia Liu,Can Zhang,Baiyi Lu,Xing Xiao,Zhonghua Liu
Acteoside, an important phenylethanol glycoside, is the main active component in Osmanthus fragrans flower. Our previous study found that acteoside showed high antiaging effect but its absorption rate was low. We speculated acteoside palliated aging-related cognitive impairment before being absorbed, that was intestinal homeostasis underlie the antiaging effect of acteoside. In this study, acteoside was confirmed to palliate cognitive impairment in d -galactose induced aging mice. Acteoside treatment dramatically reduced oxidative stress, alleviated intestinal inflammation, restored intestinal mucosal barrier, rebuilt gut microbiome structure and upregulated gut microbiome metabolites short-chain fatty acids (SCFAs) and amino acids (AAs). Furthermore, antibiotic treatment revealed that the antiaging ability of acteoside was abolished in microbiota depleted mice, which offered direct evidence for the essential role of gut microbiota in the attenuation of cognitive impairment of acteoside. Together, our study indicated that acteoside palliated cognitive impairment by regulating intestinal homeostasisand acteoside intake might be a promising nutritional intervention in prevention of neurodegenerative diseases.
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Experimental and Therapeutic Medicine
·
2023
·Vol. 26
·期 2
·1-15
·
IF 2.7
Jianxin Wang,Peng Guan,Yu Chen,Meng Xu,Na Wang,Ensheng Ji
Myocardial dysfunction is a frequent complication in patients with severe sepsis. However, effective drugs for the prevention of myocardial dysfunction and the molecular mechanisms of the disease remain elusive. The present study demonstrated that Cyclovirobuxine D (CVB‑D) could improve cardiac dysfunction in a cecal ligation and puncture (CLP) model in rodents and in a lipopolysaccharide (LPS) model in vitro. Echocardiography and histopathological examination were used to detect changes in cardiac structure and function. Kits were used to detect indicators of cardiac injury, transmission electron microscopy to detect structural changes in mitochondria and reverse transcription‑quantitative PCR to detect prostaglandin‑endoperoxide synthase 2 and hamp expression levels. L‑Glutathione and malondialdehyde levels and superoxide dismutase activity were measured using kits. Cell viability was measured with the Cell Counting Kit‑8. Iron metabolism‑related proteins, inflammatory factor levels and related pathway proteins were detected using western blot analysis. Changes in L‑type calcium currents were detected by membrane clamp, and contractility of cardiomyocytes was measured by Ion Optix. CVB‑D attenuated CLP‑induced cardiac malfunction in septic rats, with changes observed in myocardial pathological structure, creatine kinase isoenzyme (CK‑MB), lactate dehydrogenase (LDH) and cardiac troponin I (cTnI). CVB‑D attenuated sepsis‑induced lipid peroxidation and iron overload. In addition, CVB‑D decreased the expression of CK‑MB, LDH and cTnI, suppressed oxidative stress index levels and reduced the production of reactive oxygen species. CVB‑D decreased LPS‑induced cytoplasmic iron overload by increasing upregulation of iron uptake molecules. Conversely, CVB‑D significantly increased the upregulation of ferroportin 1. CVB‑D pretreatment significantly reduced the levels of hamp mRNA compared with the LPS‑treated group. CVB‑D pretreatment significantly reduced inflammatory factor levels and the ratio of phosphorylated vs. total signal transducer and activator of transcription 3. The expression of SLC7A11 and GPX4 was upregulated in septic cells pretreated with CVB‑D, however treatment with ML385 largely decreased this upregulation. Of note, CVB‑D inhibited the inward flow of calcium ions through the LTCC. In conclusion, these findings suggest that CVB‑D alleviated sepsis‑induced cardiac iron toxicity by alleviating iron metabolism.
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Nanomaterials
·
2022
·Vol. 12
·期 19
·3294
·
IF 5.719
Beenish Mustafa,Wengang Lu,Zhiyuan Wang,Fuzhuo Lian,Andy Shen,Bing Yang,Jun Yuan,Chang Wu,Yangbowen Liu,Weiwei Hu,Lei Wang,Geliang Yu
Here, rational design electrodes are fabricated by mixing MXene with an aqueous solution of chloroauric acid (HAuCl4). In order to prevent MXene from self-restacking, the groups of -OH on the surface of Ti3C2Txnanosheets underwent a one-step simultaneous self-reduction from AuCl4-, generating spaces for rapid ion transit. Additionally, by using this procedure, MXene’s surface oxidation can be decreased while preserving its physio-chemical properties. The interlayered MX/Au NPs that have been obtained are combined into a conducting network structure that offers more active electrochemical sites and improved mass transfer at the electrode–electrolyte interface, both of which promote quick electron transfer during electrochemical reactions and excellent structural durability. The Ti3C2Tx-AuNPs film thus demonstrated a rate performance that was preferable to that of pure Ti3C2Txfilm. According to the results of the characterization, the AuNPs effectively adorn the MXene nanosheets. Due to the renowned pseudocapacitance charge storage mechanism, MXene-based electrode materials also work well as supercapacitors in sulfuric acid, which is why MXene AuNPs electrodes have been tested in 3 M and 1 M H2SO4. The symmetric supercapacitors made of MXene and AuNPs have shown exceptional specific capacitance of 696.67 Fg−1at 5 mVs−1in 3 M H2SO4electrolyte, and they can sustain 90% of their original capacitance for 5000 cycles. The highest energy and power density of this device, which operates within a 1.2 V potential window, are 138.4 Wh kg−1and 2076 W kg−1, respectively. These findings offer a productive method for creating high-performance metal oxide-based symmetric capacitors and a straightforward, workable approach for improving MXene-based electrode designs, which can be applied to other electro-chemical systems that are ion transport-restricted, such as metal ion batteries and catalysis.Keywords:symmetric supercapacitors;MXene;chloroauric acid (HauCl4);energy density;power density;aqueous electrolyte;energy storage;2D materials
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高影响因子
Nanoscale
·
2021
·Vol. 13
·期 17
·8174-8180
·
IF 7.79
Zehao Gu,Mengfan Lu,Kai Feng,Zhaoxia Jin
Cellulose nanocrystals (CNCs) are inherently right-handed nanostructures that originate from nature, showing chirality in their fibrils, bundles, and self-assembled films. However, the enantio-specific interaction between CNCs and other chiral molecules has not been explored so far. In this study, we first demonstrated a chirality-related difference in the composite films of cellulose nanocrystals and histidine with a D- or L-configuration. The distinction is not only presented in the self-assembled nanostructures of CNCs, optical properties, and the thermal decomposition of composites but also in the crystallization of the amino acid. We suppose that it might have originated from the packing of amino acids on the twisted surface of CNCs. The knowledge about the enantio-specific interaction between the chiral amino acid and polysaccharide nanostructure is of significant importance for developing a new strategy for enantiomeric separation.
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Drug Design Development and Therapy
·
2020
·
IF 3.216
Hongfang Li,Yunyan Tang,Yang Wang,Weipeng Wei,Chengchen Yin,Fushang Tang
Background Bupleurum is one of the most important traditional Chinese medicines and an ingredient in many compound preparations. It is widely used together with other drugs in clinical practice, and thus there is great potential for drug–drug interactions. Saikosaponin D (SsD) is a major bioactive triterpenoid saponin extracted from Bupleurum with anti-inflammatory, anticancer, antioxidative, and antihepatic fibrosis effects. Effects of the main components of Bupleurum on cytochromes P450 (CYPs) need to be clarified in the clinical application of combination therapies of formulations containing SsD or Bupleurum . Purpose This study aimed to investigate the effects of SsD on the CYP1A2 and CYP2D6 mRNAs, protein expression, and relative enzyme activities in HepaRG cells. Methods HepaRG cells were cultured with SsD at concentrations of 0.5, 1, 5 and 10 μM for 72 hours. mRNA and protein expression of CYP1A2 and CYP2D6 were analyzed with real-time PCR and Western blot analysis. Relative enzyme activities were analyzed with HPLC based on consumption of the specific probe substrate. Results SsD significantly induced expression of mRNA and increased relative activity of CYP1A2 in HepaRG cells after the cells had been treated with SsD at concentrations of 1, 5 and 10 μM. SsD also induced protein expression of CYP1A2 at concentrations of 5 and 10 μM. SsD exhibited an inductive effect on CYP2D6 mRNA and protein expression, while increasing the relative activity of CYP2D6 at concentrations of 5 and 10 μM. Conclusion This study is the first to investigate the effect of SsD on CYP1A2 and CYP2D6 in HepaRG cells, and the results may provide some useful information on potential drug–drug interactions related to clinical preparations containing SsD or Bupleurum .
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危险品化学品经营许可证（带存储）