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antibacterial activity and Structure-activity Relationships of Schiff Bases on Staphylococcus aureus by Microcalorimetry

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Wuhan University Journal of Natural Sciences 2010年第1期15卷 71-77页

作者： HOU Hanna ZHU Juncheng QI Zude ZHOU Bo LI Meiying LIU Yi College of Chemistry and Molecular Sciences/State Key Laboratory of Virology Wuhan University Wuhan 430072 Hubei China Department of Chemistry Hubei University of Education Wmhan 430205 Hubei China

The growth of Staphylococcus aureus under the action of six kinds of Schiff bases（A,B,C,D,E,F） was studied by means of microcalorimetry. Growth constant k and inhibition ratio I were calculated. Also,the antibacterial activity,the action characteristics and the structure-activity relationships of the compounds on S. aureus were analyzed. Results indicate that B,F show good antibacterial activity（IC50：293.6 mg · L-1 and 307.8 mg · L-1） ,D,E show moderate antibacterial activity（IC50：966.3 mg · L-1 and 1 126.7 mg · L-1） ,and A,C just show weak antibacterial activity（IC50 〉1 200 mg · L-1） . The I-c curves mainly present a straight line shape for B,D,E and F,but an inverse ＂S＂ shape for A and C. Structure-activity relationships analysis suggests that the species and position of the substituents determine the antibacterial activity of these Schiff bases,and the charge density distribution is one of the most important influencing factors.

关键词： Schiff bases Staphylococcus aureus microcalorimetry antibacterial activity structure-activity relationships

antibacterial activity of Extracts from Zostera marina Against Pathogens of Apostichopus japonicus Skin Ulceration Disease

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Journal of Ocean University of China 2010年第1期9卷 68-70页

作者： LIU Yang JIANG Guoliang WU Zhiqiang College of Marine Life Sciences Ocean University of China Qingdao 266003 P. R. China

The purpose of this study was to investigate the antibacterial activity of extracts from Zostera marina against the pathogens of Apostichopus japonicus skin ulceration *** 95% ethanol (v/v) solvent was used to extract Zostera marina at 50℃,aqueous extract (ZA) showed obvious bacteriostatic effects on the tested bacterial strains (inhibition halo diameters between 8.23 mm and 13.62 mm),whereas the ethyl acetate extract (ZE) was almost *** minimal inhibitory concentration (MIC) of ZA against four pathogens were homogeneous at 12.8 g *** components were analyzed by thin layer chromatography (TLC) assay and six fractions were *** another study,the six fractions showed inhibitory effects against the tested bacteria while their functions seemed to counteract the ZA activity.

关键词： Zostera marina Apostichopusjaponicus skin ulceration disease antibacterial activity

Facile Fabrication of Hyperbranched Polyacetal Quaternary Ammonium with pH-Responsive Curcumin Release for Synergistic antibacterial activity

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Chinese Journal of Polymer Science 2023年第4期41卷 564-573,I0008页

作者： Xing Wang Ya-Qiang Wang De-Cheng Wu Beijing National Laboratory for Molecular Sciences State Key Laboratory of Polymer Physics&ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen518055China

In the current global crisis of antibiotic resistance,persuit of an effective multi-pathway collaborative approach to enhance antibacterial activity is urgently ***,a kind of hyperbranched polyacetal quaternary ammonium(Hyper-ace-QA)with efficiently antibacterial function were synthesized by a succession of efficient click *** high molecular weights can be obtained just after UV irradiation for 3 h,and the grafting ratio can be easily adjusted through controlling solvent system,molar ratio,and *** studies indicated that Hyper-ace-QA had good biocompatibility and can be used as a potential antibacterial *** importantly,after in situ encapsulation of bioactive curcumin drugs into the hyperbranched intramolecular cavities,the acid-liable acetal linkers within the hyperbranched backbone made the loading antibacterial drugs rapidly release with pH-or bacterial-responsive behaviors since many bacteria can produce acids at the infection site by the combined actions of immune response and bacterial ***,the integration of quaternary ammonium characteristics and pH-triggered curcumin release could facilitate the antibacterial activity against gram-positive Staphylococcus *** work represents a synergistic strategy on offering important guidance to rational design of multifunctional antimicrobial vehicles,which would be promising therapeutic alternatives for first aid treatment of wound infection in critical situations.

关键词： Hyperbranched polymer Acetal Quaternary ammonium pH-Responsive antibacterial activity

Controlled release and enhanced antibacterial activity of salicylic acid by hydrogen bonding with chitosan

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Chinese Journal of Chemical Engineering 2016年第3期24卷 421-426页

作者： Zujin Yang Yanxiong Fang HongbingJi School of Chemistry and Chemical Engineering The Key Laboratory of Low-carbon Chemistry&Energy Conservation of Guangdong ProvinceSun Yat-sen UniversityGuangzhou 510275China Huizhou Research Institute Huizhou 516216China Faculty of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China

Microcapsules of salicylic acid （SA） with chitosan were prepared by spray drying method. Various analytical methods were used to characterize the nature of microcapsules. Fourier-transform infrared spectroscopy （FTIR） confirmed the presence of intermolecular interactions between chitosan and SA. Particle size analysis showed that the average size ofmicrocapsules ranged from 2 to 20 pro, Scanning electron microscopy （SEM） studies indicated that the microspheres were spherical and had a relatively smooth surface. Microbiological assay of antibacterial activity for SA and its microcapsules was measured using different bacterial strains. It was found that the antibacterial activity of SA was improved after the formation of microcapsules. The in vitro release profile showed that the microcapsules could control SA release from I h to 4 h. Kinetic studies revealed that the release pattern follows Korsmeyer-Peppas mechanism. Enhanced antibacterial activity of the SA micro- capsules was attributed to the synergistic effects of intermolecular hydrogen-bonding interactions N-H...O and O-H...O=C between SA and chitosan. It was also confirmed by quantum chemical calculation.

关键词： Salicylic acid Microcapsule Release performance antibacterial activity Quantum-chemical calculations

Reduced graphene oxide (RGO) reinforced Mg biocomposites for use as orthopedic applications: Mechanical properties, cytocompatibility and antibacterial activity

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Journal of Magnesium and Alloys 2022年第12期10卷 3612-3627页

作者： Somayeh Abazari Ali Shamsipur HamidRezaBakhsheshi-Rad Department of Materials and Metallurgical Engineering Amirkabir University of TechnologyTehranIran Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran

Magnesium(Mg) has attracted wide interest in orthopedic applications as they exhibit great biodegradability and strong biocompatibility,while corrosion is the main concern for Mg that should be addressed prior to biomedical applications. In this work, ZM31(Mg-3Zn-1Mn)/x RGO(x = 0, 0.5, 1 and 1.5 wt%) biocomposites were synthesized by semi-powder metallurgy method. The results showed that the RGO acting as an effective reinforcing filler to prevent deformation and showed better compressive strength(282.3 ± 9 MPa) and revealed enhancement in failure Strain(7.8 ± 2.1%) at 1 wt% RGO concentration compared to Mg alloy(244.5 ± 9 MPa and 7.1 ± 1.5%respectively). Moreover, fracture analysis indicated a more ductile fracture of the nanocomposites after the incorporation of RGO. Crack bridging, crack deflection and crack branching are dominant mechanisms for reinforcement of Mg-based containing RGO. Mg composites containing 0.5 wt% RGO showed a low corrosion rate(2.75 mm/year), while more incorporation of RGO resulted in an increased corrosion rate(4.38 mm/year). In addition, the degradation rate of ZM31 alloy(2.57 mg·cm-2·d-1) obviously decreased with the addition of 0.5 wt%RGO(1.84 mg·cm-2·d-1) in the SBF. Besides, continuous apatite layers were created on the composites in the SBF solution. Also, the cell culture examinations showed good cell viability and adhesion on composites with 0.5 and 1 wt% RGO, which was demonstrated by the SEM and MTT assay The alkaline phosphatase(ALP) activity of the ZM3–0.5RGO composite was considerably higher than that of ZM31matrix alloy in 24 h and 48 h, implying higher osteoblastic differentiation. The antibacterial behavior toward both bacteria(E. coli and ***) exhibited that escalating RGO concentration in Mg-matrix composites leads to further inhibition of bacteria growth. These findings suggested that ZM31–0.5RGO biocomposite could be a more promising candidate for orthopedic implants.

关键词： Mg alloys Reduced graphene oxide Mechanical properties Corrosion resistance antibacterial activity Biocompatibility

Structure and antibacterial activity of Ce3+ exchanged montmorillonites

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Journal of Rare Earths 2009年第5期27卷 858-863页

作者： OUYANG Yousheng XIE Yushan TAN Shaozao SHI Qingshan CHEN Yiben Guangdong Institute of Microbiology Guangzhou 510070 China Department of Chemistry Jinan University Guang1zhou 510632 China Department of Chemistry Jinan University Guang1zhou 510632 China Guangdong Institute of Microbiology Guangzhou 510070 China Guangdong Institute of Microbiology Guangzhou 510070 China

Four kinds of Ce3+ exchanged montmorillonites (Ce/MMTs) were prepared by an ion-exchange reaction, and characterized with energy dispersive X-ray analysis (EDX), X-ray difference (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The surface properties and antibacterial activity of Ce/MMTs were also investigated. The chemical compositions of Ce/MMTs were determined, and the cerium of Ce/MMTs was confirmed to be present as trivalent cerium state. The d001 basal spacings of Ce/MMTs were enlarged with the enhancement of the cerium contents, and the particles were formed with irregular shape. On increasing the Ce contents of Ce/MMTs, the special surface areas were decreased, but the total pore volumes and the average pore sizes were increased. The antibacterial activity of Ce/MMTs is increased with increasing the cerium contents, and 1.5 g/L of Ce/MMT-3 containing 11.46wt.% of curium could remove all the Staphylococcus aureus and more than 99.9% of the Escherichia coli within 24.0 h of contact. Moreover, Ce/MMTs displayed bactericidal activity.

关键词： Ce3+ exchanged montmorillonite chemical composition microstructure antibacterial activity rare earths

Synthesis and antibacterial activity of Novel Oxazolidinone Analogs Containing Substituted Thiazole/Fused-Bicyclic Groups

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Chemical Research in Chinese Universities 2006年第4期22卷 459-464页

作者： ZHAI Xin ZHAO Yan-fang WANG Jia HONG Wei HUANG Liang GONG Ping School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 P. R. China

Sixteen novel oxazolidinone analogs containing substituted thiazole/fused-bicyclic（imidazo[ 1,2-b] pyridazine/ imidazo[2,1-b] thiazole） groups were designed and synthesized. A new method for the preparation of the key intermediate compound 11 was proposed. The structures of the target compounds were confirmed by ^1H NMR, IR and MS, and their in vitro antibacterial activities against staphylococcus aureus were evaluated. Among them, compound 16a displays a promising antibacterial activity comparable to that of linezolid.

关键词： Oxazolidinone analog Synthesis antibacterial activity

Synthesis and antibacterial activity of Selenium-functionalized Poly(ε-caprolactone)

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Chinese Journal of Polymer Science 2022年第1期40卷 67-74页

作者： Ying-Ying Li Dong Xing Xiang-Qiang Pan Jian Zhu Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationState and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsDepartment of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

A selenium-functionalizedε-caprolactone was synthesized by introducing a phenyl selenide group at the 7-position.A polymer was obtained through the ring-opening polymerization of this monomer in a base/thiourea binary organocatalytic system.A living polymerization process was achieved under mild *** resulting polymers had a controlled molecular weight with a narrow molecular weight distributions and high end-group *** copolymers could be obtained by copolymerizing this monomer withε-*** thermal degradation temperature of the obtained copolymers decreased with the increasing molar ratio of selenide functionalized monomer in copolymers,while the glass transition temperature *** addition,the phenyl selenide side group could be further modified to a polyselenonium salt,which resulted in a polymer with good antibacterial *** survival rate of *** and *** was only 9%with a polymer concentration of 62.5μg/mL.

关键词： Selenium-containing polyester Polycations antibacterial activity Degradable

Integrated two-phase free radical hydrogel:Safe,ultra-fast tooth whitening and antibacterial activity

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Journal of Materials Science & Technology 2022年第5期100卷 59-66页

作者： Lujie Zhang Jie Pan Jue Zhang Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China Department of General Dentistry Peking University School and Hospital of Stomatology&National Center of Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Laboratory for Digital and Material Technology of Stomatology&Beijing Key Laboratory of Digital StomatologyBeijing 100081China

The growing demand for brilliant smile and tooth whitening has led to the increasing significance of tooth whitening ***,the development of tooth whitening materials with high efficiency and safety has been considered to be an urgent ***,we report a novel tooth whitening strategy,which overcomes the limitation of conventional methods,shows excellent tooth whitening efficiency and safety,and even exhibits outstanding antibacterial *** by stomata and chloroplasts in green leaves,we have developed an integrated two-phase free radical hydrogel(TP-GEL),which integrates solid-phase and liquid-phase free radical functional components fabricated by cold plasma ***-GEL demonstrated safe and ultrafast tooth-whitening effect with or without visible light,which can be more significant than that of 30% H_(2)O_(2),the commonly whitening material in dental clinical *** importantly,we also avoid the damage to enamel,such as microhardness,roughness,surface *** from free radicals,much higher antibacterial properties than commercial products(Chlorhexidine)was *** research provides fundamental design criteria for the development of dual functional oral health care materials with advanced tooth whitening and antibacterial activity.

关键词： Tooth whitening Integrated two-phase material Free radical Safety antibacterial activity