共查询到19条相似文献,搜索用时 78 毫秒
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合成了一系列不同银含量的硫脲壳聚糖-银配合物;利用傅立叶变换红外光谱分析了合成产物的结构,并测定了壳聚糖、硫脲壳聚糖及4种硫脲壳聚糖-Ag配合物对细菌和植物病原菌的抑菌性能.结果表明:硫脲壳聚糖-Ag配合物的抑菌性能优于单一的壳聚糖和硫脲壳聚糖;随着硫脲壳聚糖-Ag配合物中银含量的增大,抑菌效果明显增强. 相似文献
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用体外抑菌法研究了O-羧甲基壳聚糖镧、O-羧甲基壳聚糖钕配合物对大肠杆菌(E.coli)、金黄色葡萄球菌(St.aureus)、阴沟肠杆菌(E.cloacae)、枯草芽孢杆菌(B.subtilis)、粪肠杆菌(E.faecalis)和肺炎克罗伯杆菌(S.pneumoniae)的抑菌活性。采用紫外光谱研究了两种O-羧甲基壳聚糖稀土配合物与小牛胸腺DNA的相互作用。结果表明:O-羧甲基壳聚糖稀土配合物均有抑菌活性,且O-羧甲基壳聚糖稀土配合物与DNA以静电作用为主,能使DNA双螺旋结构破坏。 相似文献
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以壳聚糖(CTS)、水杨醛(Sal)、2-羟基-4-甲氧基苯甲醛(2-Hy)、香草醛(Val)和邻香草醛(O-val)为原料,经过缩合反应得到四种壳聚糖衍生物(CTS-Sal,CTS-2Hy,CTS-Val,CTS-O-val),采用红外光谱(FT-IR)和紫外分光光谱(UV)对结构进行了表征。通过微量液体稀释法和真菌菌丝生长速率法测定了四种衍生物对灰霉菌的最小抑菌浓度(MIC)和半抑制量浓度(EC50)。结果表明,与CTS相比,四种衍生物对灰霉菌均有明显抑制作用,其中CTS-2Hy的MIC和EC50均最小,分别为1 184.49μg·m L-1和724.44μg·m L-1。 相似文献
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Luminita Georgeta Confederat Cristina Gabriela Tuchilus Maria Dragan Mousa Shaat Oana Maria Dragostin 《Molecules (Basel, Switzerland)》2021,26(12)
Despite the advantages presented by synthetic polymers such as strength and durability, the lack of biodegradability associated with the persistence in the environment for a long time turned the attention of researchers to natural polymers. Being biodegradable, biopolymers proved to be extremely beneficial to the environment. At present, they represent an important class of materials with applications in all economic sectors, but also in medicine. They find applications as absorbers, cosmetics, controlled drug delivery, tissue engineering, etc. Chitosan is one of the natural polymers which raised a strong interest for researchers due to some exceptional properties such as biodegradability, biocompatibility, nontoxicity, non-antigenicity, low-cost and numerous pharmacological properties as antimicrobial, antitumor, antioxidant, antidiabetic, immunoenhancing. In addition to this, the free amino and hydroxyl groups make it susceptible to a series of structural modulations, obtaining some derivatives with different biomedical applications. This review approaches the physico-chemical and pharmacological properties of chitosan and its derivatives, focusing on the antimicrobial potential including mechanism of action, factors that influence the antimicrobial activity and the activity against resistant strains, topics of great interest in the context of the concern raised by the available therapeutic options for infections, especially with resistant strains. 相似文献
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酰基硫脲化合物的合成及其生理活性 总被引:22,自引:0,他引:22
通过酰基异硫氰酸酯与胺类化合物的加成反应,合成了15种酰基硫脉类化合物,化合物的结构经元素分析、IR、 ̄1HNMR等确证,初步生理活性实验表明,化合物2_j,2_1对玉米种子的萌发和幼苗叶中的呼吸速率、叶绿素含量有显著促进效应。 相似文献
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This study aimed at the development of antimicrobial (AM) packaging based on wheat starch incorporated with chitosan and lauric acid as antimicrobial agents. A series of blends with different ratio of starch, chitosan and lauric acid (S:C:LA) were prepared by casting method. Effects of incorporation of antimicrobial agents into starch-based film were investigated in order to improve the spectrum activity based on measured distributions of inhibitory results. The diffusivity equation approach for describing the antimicrobial effects was also extended to include information about the molecular size of particles in the formed matrices. The Agar Disc Diffusion Assay and Liquid Culture Test measure the distributions of inhibitory effect towards type of bacterial contamination in terms of Gram-positive, Gram-negative and their combination of wider spectrum activity in the blend films. For the first time, the inhibition size distribution resulting from rationing of base polymers and lauric acid as filler in the starch-base film itself was quantified. Spectrum activity of different Gram-stained bacteria as measured by the bacterial growth inhibition, gave surprisingly consistent pattern on rationing of compositions in the film. This indicates that the spectrum activity produced by the antimicrobial components can be related directly to the ratio on blending during film preparation. This phenomenon is proven by dominating of chitosan (S:C:LA ratio 1:9:0.08 to 3:7:0.24) for 48% increase of effective E. coli inhibition (Gram-negative bacteria). More positively, however, it signifies that the affinity of lauric acid towards starch as reported by previous researches indicates relatively unambiguously the ratio required to achieve a constant degree of B. subtilis (Gram-positive) bacterial inhibition from starch/lauric acid dominating of S:C:LA ratio at 4:6:0.32 to 7:3:0.56. Furthermore, S:C:LA ratio 8:2:0.64 and 9:1:0.72 showed good synergic inhibition of 54% higher relative to sole chitosan towards both bacteria. Further studies of antimicrobial effects investigated the mode of release from the base film. The release of lauric acid in fatty acid food stimulant was satisfactorily expressed by Fickian-diffusion mechanism described by zero order kinetics which indicated that lauric acid released from the film matrix remains constant over time. 相似文献
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The title complex [NiL]·H2O(C20H24N2NiO5,L = paeonol-ehylenediamine) was synthesized by the hydrothermal method and characterized by IR,cyclic voltammetry and X-ray single-crystal diffraction.The complex belongs to the monoclinic system,space group P21/c with a=13.4361(13),b=7.3290(10),c=20.981(2),β=109.244°,V=1950.6(4)3,Z=4,F(000)=904,Dc=1.468 g/cm3,μ(MoKα)=1.029 mm-1,the final R=0.0588 and wR=0.1577.The complex exhibits antimicrobial activities(antimicrobial activities against Staphylococcus aureus and Escherichia codi) by agar diffusion measurement. 相似文献
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Poowadon Muenraya Somchai Sawatdee Teerapol Srichana Apichart Atipairin 《Molecules (Basel, Switzerland)》2022,27(18)
Colistin is a potent peptide antibiotic that is effective against Gram-negative bacteria. However, nephrotoxicity limited its clinical use. Silver nanoparticles (AgNPs) have gained attention as a potential antimicrobial agent and nanodrug carrier. The conjugation of antibiotics and AgNPs has been found to increase the activity and decrease drug toxicity. In this study, colistin was conjugated with AgNPs (Col-AgNPs), which was confirmed by Fourier-transform infrared (FT-IR) and energy-dispersive X-ray (EDX) spectra. The optimized Col-AgNPs had the proper characteristics, including spherical shape, monodispersity, nanosized particle, high surface charge, and good stability. The powder X-ray diffraction (PXRD) pattern supported the crystallinity of Col-AgNPs and AgNPs. The drug loading of Col-AgNPs was 11.55 ± 0.93%. Col-AgNPs had higher activity against Gram-negative bacteria (Escherichia coli, Klebsiella pneumonia, and Pseudomonas aeruginosa) than AgNPs and colistin. The mechanism of actions of Col-AgNPs involved membrane disruption and genomic DNA damage. The Col-AgNPs and AgNPs were biocompatible with human red blood cells and renal cells at concentrations up to 16 µg/mL. Interestingly, Col-AgNPs exhibited higher cell survival than AgNPs and colistin at 32 µg/mL. Our results revealed that the Col-AgNPs could enhance the antimicrobial activity and cell biocompatibility more than colistin and AgNPs. 相似文献
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A new nickel(II) complex, C34H38N8NiO4, has been prepared and charac- terized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group P21/c with a = 11.715(5), b = 12.328(5), c =11.113(5) , β = 92.589(5)°, Z = 2, Dc = 1.411 g/cm3, μ = 0.658 mm-1, the final R = 0.0427 and wR = 0.1099 for 2229 observed reflections with I > 2σ(I). The complex is a centrosymmetric plane in which nickel(II) is coordinated in a regular octahedron to the ligand phenytoin through the nitrogen atoms of ethylenediamine, imine and amine. The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method, and found to be active against the four test bacterial organisms. Preliminary screening for antimicrobial activities showed that the title complex is quite active against standard strains of Salmonella species, Staphylococcus aureus, Bacillus pumilus and Eschierichia coli. 相似文献
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以乙二醇二缩水甘油醚(GDE)为偶联剂,将胍盐低聚物(PHMG)接枝到淀粉上,形成淀粉接枝物(Starch-g-PHMG)。然后,将一定比例的Starch-g-PHMG与淀粉-丙烯酸接枝共聚物共混,制备了抗菌水凝胶敷料(AHD)。通过红外光谱(FT-IR)、元素分析确定了Starch-g-PHMG的分子结构;通过吸液测试、抗菌测试表征了AHD的理化性能。结果表明:在反应温度为60°C,反应时间为3h,w(NaOH)=0.4%时,Starch-g-PHMG中PHMG的接枝效率最高,可达37.5%;AHD的吸液率随着Starch-g-PHMG含量的增加而减少;当w(PHMG)0.33%时,AHD对金黄色葡萄球菌与大肠杆菌的抑菌率可以达到100%。 相似文献