INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2022
·Vol. 24
·期 1
·335
·
IF 6.208
Yajing Yang,Guoqiang Chen,Xiaoqi Zhao,Xiaohe Cao,Lei Wang,Jingjiu Mu,Fenghui Qi,Lijuan Liu,Haibo Zhang
Exopolysaccharides produced by edible microorganisms exhibit excellent constructive physicochemical and significant biological activity, which provide advantages for the food or pharmaceutical industries. Two novel exopolysaccharides produced byDebaryomyces hanseniiDH-1 were characterized, named S1 and S2, respectively. S1, with a molecular weight of 34.594 kDa, primarily consisted of mannose and glucose in a molar ratio of 12.19:1.00, which contained a backbone fragment of α-D-Manp-(1→4)-α-D-Manp-(1→2)-α-D-Glcp-(1→3)-α-D-Manp-(1→3)-β-D-Glcp-(1→4)-β-D-Manp-(1→. S2, with a molecular weight of 24.657 kDa, was mainly composed of mannose and galactose in a molar ratio of 4.00:1.00, which had a backbone fragment of α-D-Manp-(1→6)-β-D-Manp-(1→2)-α-D-Manp-(1→4)-α-D-Galp-(1→3)-β-D-Manp-(1→6)-α-D-Manp-(1→. Both S1 and S2 exhibited good thermal stability and potent hydroxyl radical scavenging activity, with ~98%. Moreover, S1 possessed an additional strong iron-reducing capacity. In vitro antitumor assays showed that S1 and S2 significantly inhibited the proliferation of Hela, HepG2, and PC-9 cancer cells. Moreover, PC-9 was more sensitive to S1 compared with S2. The above results indicate that S1 and S2 have great potential to be utilized as natural antioxidants and candidates for cancer treatment in the food and pharmaceutical industries.Keywords:Debaryomyces hansenii;exopolysaccharides;structure analysis;antioxidant activity;antitumor activity;thermal property
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Molecular Catalysis
·
2022
·
IF 5.089
Nan Li,Changping Jian,Yaping Song,Li Wang,Ata Ur Rehman,Yanghe Fu,Fumin Zhang,De-Li Chen,Weidong Zhu
Herein, we reported a facile and scalable approach for the synthesis of Fe-based MOF MIL-88A(Fe) via a simple liquid-phase route at atmosphere pressure, and its application as a heterogeneous catalyst for the efficient aerobic oxidation of cyclohexene to value-added 2-cyclohexene-1-ol. Over 130 g of spindle-shaped MIL-88A(Fe) nanocrystals with high crystallinity, monodispersed particle size, and large specific surface area were easily synthesized per batch according to our method. The resultant MIL-88A(Fe) exhibited a high catalytic activity (conversion: 81%) with 70% selectivity for 2-cyclohexene-1-ol in the aerobic oxidation of cyclohexene with O 2 as the sole oxidant under mild reaction conditions (0.5 MPa of O 2 , 353 K for 8 h), outperforming the analogues reported in the literatures. The combined experimental and theoretical approach support the reaction mechanism of the oxidation of cyclohexene via both the free radical reaction pathway and Fe-mediated reaction pathway, resulting in the selective formation of 2-cyclohexene-1-ol.
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ACS Omega
·
2023
·
IF 4.1
Haoyue Hao,MengYao Zhu,Liang Li
In this paper, Er3+/Yb3+ codoped Y2(1–x%)Lu2x %O3 solid solution was prepared through the sol–gel method, and the substitution of Y3+ by Lu3+ ions in Y2O3 was confirmed by X-ray diffraction data. The up-conversion emissions of samples under 980 nm excitation and the relative up-conversion processes are investigated. The emission shapes do not vary with the change in doping concentration due to the unaltered cubic phase. The red-to-green ratio changes from 2.7 to 7.8 and then declines to 4.4 as the doping concentration of Lu3+ increases from 0 to 100. The emission lifetimes of green and red have similar variation: the emission lifetime decreases with doping concentration changing from 0 to 60 and rises as the doping concentration continues to increase. The reason why the emission ratio and lifetime change could be originated to the exacerbation of cross-relaxing process and the change of radiative transition probabilities. The temperature-dependent fluorescence intensity ratio (FIR) shows that all samples can be used in noncontact optical temperature sensing, and the method of local structure distortion can be used to improve sensitivity further. The max sensing sensitivities of FIR based on R538/563 and Rred/green reach 0.011 K–1 (483 K) and 0.21 K–1 (300 K). The results display that Er3+/Yb3+ codoped Y2(1–x %)Lu2x %O3 solid solution can be potential candidates for optical temperature sensing in different temperature ranges.
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Acta Pharmaceutica Sinica B
·
2022
·
IF 14.903
Jingwen Dong,Chenfei Zhu,Ying Huang,Quanhao Li,Jing Li,Zheng Wang,Yixin Wang,Zhanwei Zhou,Minjie Sun
Fibrosis is one of the key factors that lead to the immune exclusion of solid tumors. Although degradation of fiber is a promising strategy, its application was still bottlenecked by the side effects of causing metastasis, resulting in the failure of immunotherapy. Here, we developed an antimetastatic polymer (HPA) for the delivery of chemo-drug and antifibrotic siPAI-1 to form the nano-permeator. Nano-permeator shrank after protonation and deeply penetrated into the tumor core to down-regulate the expression of PAI-1 for antifibrosis, and further promoted the sustained infiltration and activation of T cells for killing tumor cells. Moreover, metastasis after fiber elimination was prevented by multivalent CXCR4 antagonistic HPA to reduce the attraction of CXCL12 secreted by distant organs. The administration of stroma-alleviated immunotherapy increased the infiltration of CD8 + T cells to 52.5% in tumor tissues, inhibiting nearly 90% metastasis by HPA in distant organs. The nano-permeator reveals the mechanism and correlation between antifibrosis and antimetastasis and was believed to be the optimizing immunotherapy for solid fibrotic tumors.
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高影响因子
GREEN CHEMISTRY
·
2023
·Vol. 25
·期 5
·1823-1834
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IF 9.8
Ying Duan,Chi Zhang,Dongsheng Deng,Dong Sui,Xiaohan Gao,Yanliang Yang
The rearrangement of furan rings for valuable chemicals is an important topic for biomass conversion. In this study, 2,5-di(hydroxymethyl)furan (BHMF) was selectively converted to 6-methyldihydro-2H-pyran-3(4H)-one (MDPO) and 1-hydroxy-2,5-hexanedione (HHD) under atmospheric H2 pressure in water. The selectivity to MDPO or HHD could be regulated by a catalyst. The parameters (temperature, pH, catalyst loading, and BHMF concentration) for the transformation of BHMF were studied. The selectivity for the transformation of BHMF was very sensitive to the reaction conditions, especially for the conversion of BHMF to MDPO. 68% selectivity to MDPO on Pd/C and 72% selectivity to HHD on Rh/C were achieved under the optimized conditions. Both Pd/C and Rh/C could be reused at least 5 times without the loss of activity. The fresh and used Pd/C and Rh/C were characterized by XRD, XPS, SEM, TEM, EDS mappings and ICP-OES to study the changes during the reaction. The reaction process was studied through controlled experiments, and 6-methylene-2H-pyran-3(6H)-one (MEPO) and 6-hydroxy-6-methyl-2H-pyran-3(6H)-one (HMPO) were identified as intermediates. A reasonable reaction mechanism was proposed and the different selectivity to MDPO and HHD was well explained based on the controlled experiments and DFT calculations. The conditional sensitivity for the selectivity to MDPO and HHD could also be interpreted by the proposed reaction pathway.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
·
IF 8.2
Yan Hao,Jing Qu,Lei Tan,Zunyi Liu,Yicheng Wang,Tingrui Lin,Hui Yang,Jing Peng,Maolin Zhai
An eco-friendly superabsorbent polymer (SAP) was prepared by grafting 2-acrylamido-2-methyl-1-propanesulfonic acid onto microcrystalline cellulose in lithium chloride/ N, N -dimethylacetamide system. The synthesized SAP (cellulose- g -PAMPS) was characterized by FTIR, TGA , SEM, 1 H NMR, 13 C NMR and XRD. The water absorption equilibrium of cellulose- g -PAMPS could be achieved within 10 min in distilled water. Moreover, the maximum water absorption capacities of cellulose- g -PAMPS in distilled water, 0.9 wt% NaCl solution and 3.2 wt% Na 2 CO 3 solution were 648.9, 298.4 and 207.3 g·g −1 , respectively. The water absorption behavior of cellulose- g -PAMPS was interpreted by the pseudo-second-order model. Furthermore, cellulose- g -PAMPS could be used in some extreme conditions due to its high acid and alkali resistance. The water retention rate of cellulose- g -PAMPS could be maintained above 90 % at 25 °C for 6 h. As a consequence, the synthesized SAP can be applied to increase the plant growth and survival time under drought conditions, even under saline alkali conditions.
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RESEARCH ON CHEMICAL INTERMEDIATES
·
2022
·Vol. 49
·期 1
·241-252
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IF 3.134
Xing Qianqian,Zhao Jiancheng,Zhu Yulei,Hou Xianglin,Wang Yingxiong
5-Chloro-2-pentanone (5C2P) and its derivatives are widely utilized in the pharmaceutical and agrochemical industry. A new catalytic approach was proposed to convert 3-acetyl-1-propanol to 5C2P using bis(trichloromethyl)carbonate (triphosgene, BTC) as the efficient chlorine source. Various qualitative and quantitative nuclear magnetic resonance techniques ( 1 H, 13 C NMR), especially 1D selective gradient total correlation spectroscopy (Sel-TOCSY) and 2D heteronuclear single quantum correlation ( 1 H- 13 C HSQC) were used in the process. The reaction conditions, such as temperature, time, mole ratio, solvent as well as initiator were optimized. Experiment results showed that the yield of 5C2P reached a maximum of 97.93% in 1,2-dichloroethane at 80 °C after 2 h under the initiation of N,N-dimethylacetamide, and the optimal molar ratio of 3-acetyl-1-propanol to BTC was 1:0.4. The reaction mechanism was proposed and confirmed accordingly. Interestingly, an intermediate product of 1-(dimethylamino)ethyl carbonochloridate was observed, and its chemical structure was characterized by both Sel-TOCSY and 1 H- 13 C HSQC. This study enriched the catalytic reaction ways for the preparation of 5C2P.
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Frontiers in Pharmacology
·
2023
·
IF 5.6
Gao Rongyin,Zhang Ximei,Zou Kun,Meng Duo,Lv Jinpeng
Cutaneous pigmentation was recently shown to be an event regulated by clock proteins. Cryptochrome (CRY) is a key protein composing the feedback loop of circadian clock, however, the function of CRY in melanocytes remains unclear. Here, we found that KL001, a synthetic small molecule modulator of CRY1, inhibited melanin synthesis, as well as reduced melanocyte dendrite elongation and melanosome transport. In addition, the dominant role of CRY1 in KL001-induced anti-melanogenesis was revealed by small interfering RNA transfection. Cellular tyrosinase activity and expression level of melanogenic proteins, including tyrosinase, TRP-1, TRP-2, and transport proteins like Rab27a, Cdc42 and Myosin Va induced by α-MSH were remarkably reversed after KL001 treatment. Mechanistically, CRY1 activation inhibited melanogenesis through CREB-dependent downregulation of MITF and CREB phosphorylation was mediated by classical cAMP/PKA pathway. In addition, the other CRY1 activator, KL044 also suppressed cAMP/PKA/CREB pathway and inhibited melanogenesis. Finally, anti-melanogenic efficacy of KL001 was confirmed by determination of melanin contents in UVB-tanning model of brown guinea pigs, which indicated that targeting CRY1 activity, via topical application of small molecule activator, can be utilized therapeutically to manage human pigmentary disorders.
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DESALINATION
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2023
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IF 9.9
Yanshao Yang,Zhenggong Wang,Zejun Song,Dixin Liu,Jiaqi Zhang,Lele Guo,Wangxi Fang,Jian Jin
Despite the commercial success of polyamide reverse osmosis (RO) membranes for desalination , shortcomings of the material intrinsic properties hinder the further improvement of RO membrane permselectivity towards more energy-efficient desalination. Exploring new polymer materials is thus important to overcome the limitation of existing RO membrane materials. This work reports an investigation on an amidoxime modified polymer of intrinsic microporosity (AOPIM-1) as a membrane material for reverse osmosis desalination. AOPIM-1 is casted into a defect-free dense membrane , and followed by a thermal treatment to finetune its structural feature for enhanced salt rejection. As a polymer with stiff and distorted backbone structure, thermal treated AOPIM-1 possesses a high free volume and highly connected 0.3–0.8 nm micropores that provide fast water transport routes while regulating the permeation of ions. The rapid transport through the microporous channels gives the AOPIM-1 membrane a water permeability of 1.92 × 10 −7 m·kg/m 2 ·h·bar with NaCl rejection as high as 98.5 %. The thickness-normalized water permeability of AOPIM-1 membrane exhibits order-of-magnitude improvement comparing to conventional polyamide-based desalination membranes , and the permselectivity of the membrane is also found to be on the high side. This study confirms the possibility of utilizing microporous polymers as reverse osmosis membrane materials for high performance desalination.
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Materials
·
2022
·Vol. 15
·期 23
·8285
·
IF 3.748
Shu-Ming Cui,Saud Hashmi,Wen-Qiang Li,Stephan Handschuh-Wang,Cheng-Tian Zhu,Shi-Chang Wang,Pian-Pian Yang,Yan-Fei Huang,Guang-Ming Zhu,Florian J. Stadler
The dispersibility of flexible polymer chains present at the emulsion’s interface between the dispersed and continuous phase has obvious effects on rheology and dielectric properties of the whole emulsion. Cellulose nanofiber (CNF)-based Pickering emulsions are good systems to research these properties with respect to their microscopic phase structure, dielectric, and rheological properties by using CNF as a water-dispersible Pickering emulsifier, liquid paraffin as an oil phase, and didodecyldimethylammonium bromide (DDAB) as a cationic auxiliary surfactant. The CNF and DDAB contents were systematically varied while the water-to-paraffin oil ratio was kept constant to discern the influence of the Pickering emulsifiers. Polarized optical microscopic images reveal that the droplets tend to shrink at higher CNF content but grow bigger when increasing the DDAB content, which is proved by fluorescence analysis of the CNF dispersibility with varying DDAB content. The dielectric damping exhibits a minimum, whose value decreases with increasing DDAB and CNF content. Increasing the DDAB content promotes the solubilization of CNF in the aqueous phase, which will increase the overall viscosity and yield points. Similarly, a higher CNF content leads to a higher viscosity and yield point, but at high DDAB contents, the viscosity function exhibits an S-shape at intermediate CNF contents. To evaluate the results further, they were compared with CNF dispersions (without oil phase), which showed a surfactant effect slightly on maximum stress but strongly on yield stressτy, indicating that DDAB can promote the formation of a CNF network rather than the viscosity of the whole system. This paper provides information on how a systematical variation of the composition influences morphology and physico-chemical interactions as detected by broadband dielectric spectroscopy and rheological behavior.Keywords:cellulose nanofibers;CNF networks;physical entanglement;droplets clusters;startup flow
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International Journal of Electrochemical Science
·
2023
·
IF 1.5
Yanyan Xu,Wenwen Xiao,Pengli Ge,Wenguang Zeng,Qingshan Liu,Zhengyuan Gao,Yongbo Yan
This work aimed to develop a high-efficiency and reliable alternative for conventional and toxic corrosion inhibitor. A novel tetrazole derivative (1-Phenyltetrazole-5-thiol, PTT) that possessed excellent anti-corrosion capacity was exploited for the first time. Based on the traditional electrochemical investigation, morphological observation, and computer modeling, inhibition ability and adsorption type of PTT for X70 steel in 0.5 M H 2 SO 4 were varied. The electrochemical results showed that PTT was a mixed organic inhibitor, which could retard charge transfer impedance, and slowed down the corrosion rate of steel. Specifically, the highest inhibition efficiency was 95.1% when the added PTT dose was 2 mM. The adsorption model showed that the PTT film was formed via powerful physicochemical adsorption. As shown in theoretical calculations, the lower Δ E , higher μ values and E binding value of PTT corresponded to supreme adsorption performance, which was also a manifestation of the PTT high-efficiency corrosion inhibition.
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International Journal of Electrochemical Science
·
2023
·
IF 1.5
Kangquan Qiao,Ying Zeng
The inhibition effect of Diantipyrylmethane (DAM) and its synergistic effect with potassium thiocyanate (KSCN) on mild steel corrosion in 1 M HCl solution were investigated by electrochemical methods, gravimetric analysis and scanning electron microscopy (SEM). The experiment results show that the inhibition efficiency increases with the concentration of DAM alone and increases further with the presence of 2 mM KSCN. The synergism parameters demonstrate that DAM cation has a significant synergistic effect with thiocyanate anion, which is agree with the corresponding thermodynamic and kinetic parameters. The results of quantum chemical calculation confirm that the dication structure of DAM molecule in acid medium plays a vital role during corrosion inhibition of mild steel.
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