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1.
Two new oxazole/thiazole derivatives, named tetroazolemycins A (1) and B (2), have been isolated from the acetone extract of the mycelium of Streptomyces olivaceus FXJ8.012 derived from deep-sea water, together with three known compounds, spoxazomicins A–C (3–5), isolated from the fermentation supernatant. The planar structure and relative configuration of tetroazolemycins were elucidated by a combination of spectroscopic analyses, including 1D- and 2D-NMR techniques, and showed to be new pyochelin-type antibiotics. Both compounds showed metal ion-binding activity and their Zn2+ complexes exhibited weak activity against pathogenic bacteria Klebsiella pneumoniae.  相似文献   

2.
Electromagnetic shielding polyester fabrics were prepared using carboxymethyl chitosan-palladium (CMCS-Pd) complexes as activation solution, followed by electroless nickel plating. CMCS-Pd complexes were prepared by the complexing adsorption between CMCS and Pd2+. The effects of reaction time and pH value on the adsorption of Pd2+ by CMCS were discussed. The maximum adsorption capacity was calculated as 4.27 mmol/g. CMCS-Pd complexes were characterized by ultraviolet (UV) spectrophotometer and Fourier transform-infrared (FTIR) spectroscopy. The induction time of electroless plating decreased gradually with the increase of Pd2+ concentration. The lowest surface resistance 125 mΩ/sq of the treated polyester fabric was obtained when Pd2+ concentration in CMCS-Pd complex was 1.5 g/l. The prepared polyester fabrics had excellent electromagnetic shielding effectiveness (SE) of 40–60 dB. The treated polyester fabrics were also characterized by scanning electron microscopy (SEM). Results showed that CMCS-Pd was effective to form an active catalyzed layer on polyester substrate and the 1.5 g/l Pd2+ was sufficient to initiate electroless nickel plating reaction. The CMCS-Pd complex activation and electroless nickel plating treatment caused small changes in the polyester fabrics’ tensile strength and air permeability.  相似文献   

3.
Cyclopeptides usually play a pivotal role, either in the viability or virulence of fungi. Two types of cyclopeptides, six new hydroxamate siderophore cyclohexapeptides (1–6), including acremonpeptides E and F, and their complexes with aluminum and ferric ions; one new cyclic pentapeptolide, aselacin D (9); together with a known compound, aselacin C (10), were isolated and characterized from the sponge-derived fungus Acremonium persicinum F10. In addition, two new siderophore analogues chelating gallium ions (Ga3+), Ga (III)-acremonpeptide E (7) and Ga (III)-acremonpeptide F (8), using isolated acremonpeptides E and F, were prepared. The planar structures of 1–10 were elucidated by HRESIMS and (1D and 2D) NMR. The absolute configurations of amino acids were determined by means of the advanced Marfey’s method and X-ray single-crystal diffraction analysis. X-ray fluorescence (XRF) spectrometer was performed to disclose the elements of compound 1, indicating the existence of aluminum (Al). Al (III)-acremonpeptides E (1), Ga (III)-acremonpeptides E (5), Al (III)-acremonpeptide F (7), and Ga (III)-acremonpeptide F (8) displayed high in vitro anti-fungal activities, which are comparable to amphotericin B, against Aspergillus fumigatus and Aspergillus niger.  相似文献   

4.
Antimetastatic properties on both murine and human osteosarcoma cell lines (POS-1 and KHOS) have been evidenced using exopolysaccharide (EPS) derivatives, produced by Alteromonas infernus bacterium. These derivatives had no significant effect on the cell cycle neither a pro-apoptotic effect on osteosarcoma cells. Based on this observation, these EPSs could be employed as new drug delivery systems for therapeutic uses. A theranostic approach, i.e., combination of a predictive biomarker with a therapeutic agent, has been developed notably by combining with true pair of theranostic radionuclides, such as scandium 47Sc/44Sc. However, it is crucial to ensure that, once complexation is done, the biological properties of the vector remain intact, allowing the molecular tropism of the ligand to recognize its molecular target. It is important to assess if the biological properties of EPS evidenced on osteosarcoma cell lines remain when scandium is complexed to the polymers and can be extended to other cancer cell types. Scandium-EPS complexes were thus tested in vitro on human cell lines: MNNG/HOS osteosarcoma, A375 melanoma, A549 lung adenocarcinoma, U251 glioma, MDA231 breast cancer, and Caco2 colon cancer cells. An xCELLigence Real Cell Time Analysis (RTCA) technology assay was used to monitor for 160 h, the proliferation kinetics of the different cell lines. The tested complexes exhibited an anti-proliferative effect, this effect was more effective compared to EPS alone. This increase of the antiproliferative properties was explained by a change in conformation of EPS complexes due to their polyelectrolyte nature that was induced by complexation. Alterations of both growth factor-receptor signaling, and transmembrane protein interactions could be the principal cause of the antiproliferative effect. These results are very promising and reveal that EPS can be coupled to scandium for improving its biological effects and also suggesting that no major structural modification occurs on the ligand.  相似文献   

5.
Lignosulfonates (LS) were used to modify the surface of a mica substrate using Cu2+ as the binding agent through layer-by-layer (LbL) self-assembly. The average thickness and roughness of the self-assembled multilayer of LS–Cu2+ complexes increased with the number of layers as revealed by atomic force microscopy. The hydrophilicity of the modified surface decreased with the increase in the number of layers. The contact angle was increased from 6.5° to 86° after the mica surface was coated with 18 layers of LS–Cu2+ complexes. This suggests that surface hydrophilicity can be modified in a controllable manner via LbL assembly of lignosulfonates.  相似文献   

6.
Ionic conductivity and mechanical properties of a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresin type M (CRM) with various lithium salts and plasticizer were examined. The CRM used was a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) with a molar ratio of 1:1, mixed plasticizer was ethylene carbonate (EC) and propylene carbonate (PC) at a volume ratio of 1:1. The conductive behavior of polymer electrolytes in the temperature range of 298∼338 K was investigated. The PEG/LiClO4 complexes exhibited the highest ionic conductivity of ∼10−5 S/cm at 25°C with the salt concentration of 1.5 M. In addition, the plasticized PEG/LiClO4 complexes exhibited improvement of ionic conductivity. However, their complexes showed decreased mechanical properties. The improvement of ionic conductivity and mechanical properties could be obtained from the polymer electrolytes by using CRM. The highest ionic conductivity of PEG/CRM/LiClO4/(EC-PC) was 5.33×10−4 S/cm at 25°C.  相似文献   

7.
Gliadins were extracted from hard red spring wheat flour with 70% (v/v) aqueous ethanol and lyophilized. These crude gliadins were dissolved in 70% (v/v) aqueous ethanol or 4 mM acetic acid with or without ultrasonication. Precise measurements of the density and ultrasound velocity of the solutions were made at 20 °C. For non-sonicated solutions, crude gliadins solubilized in ethanol had a slightly larger partial specific volume (0.76 cm3 g−1), and a larger partial specific adiabatic compressibility coefficient (15 × 10−11 Pa−1) compared to those solubilized in acid (0.739 cm3 g−1, 3.1 × 10−11 Pa−1, respectively). Larger values are consistent with the existence of complexes formed by gliadins and lipids in aqueous ethanol solutions. Utrasonication had no effect on these protein–lipid complexes based on measurements of density, but it did alter the compressibility of gliadins in dilute acid (making them almost twice as compressible). Novel insights into gluten protein properties can be gained from compressibility measurements of solutions using ultrasonic resonators when coupled with measurements of protein specific volume.  相似文献   

8.
A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m2 g-1, 0.783 cm3 g-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g-1 for BC-GR and 842.5 mg g-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible.  相似文献   

9.
Since protein aggregation and formation of a continuous protein matrix in rye dough is very limited, an enzyme-induced protein aggregation method to improve the baking properties was investigated. The effects of microbial transglutaminase (TG) on the properties of rye dough were studied by rheological tests, confocal laser scanning microscopy (CSLM), standard-scale baking tests and crumb texture profile analysis. Addition of TG in the range of 0-4000 Ukg−1 rye flour modified the rheological properties of rye flour dough, resulting in a progressive increase of the complex shear modulus (|G∗|) and in a decrease of the loss factor (tan δ) due to protein cross-linking or aggregation. CLSM image analysis illustrated a TG-induced increase of the size of rye protein complexes. Standard baking tests showed positive effects on loaf volume and crumb texture of rye bread with TG applied up to 500 Ukg−1 rye flour. Higher levels of TG (500 U ≤ TG ≤ 4000 U) had detrimental effects on loaf volume. Increasing TG concentration resulted in an increase of crumb springiness and hardness. In conclusion, the results of this work demonstrated that TG can be used to improve the bread making performance of rye dough by creating a continuous protein network.  相似文献   

10.
Deep-sea sediment-derived bacterium may make full use of self-genes to produce more bioactive metabolites to adapt to extreme environment, resulting in the discovery of novel metabolites with unique structures and metabolic mechanisms. In the paper, we systematically investigated the metabolites in structurally diversity and their biosynthesis from the deep-sea sediment-derived bacterium Agrococcus sp. SCSIO 52902 based on OSMAC strategy, Molecular Networking tool, in combination with bioinformatic analysis. As a result, three new compounds and one new natural product, including 3R-OH-1,6-diene-cyclohexylacetic acid (1), linear tetradepsipeptide (2), N1,N5-di-p-(EE)-coumaroyl-N10-acetylspermidine (3) and furan fatty acid (4), together with nineteen known compounds (5–23) were isolated from the ethyl acetate extract of SCSIO 52902. Their structures were elucidated by comprehensive spectroscopic analysis, single-crystal X-ray diffraction, Marfey’s method and chiral-phase HPLC analysis. Bioinformatic analysis revealed that compounds 1, 3, 9 and 13–22 were closely related to the shikimate pathway, and compound 5 was putatively produced by the OSB pathway instead of the PKS pathway. In addition, the result of cytotoxicity assay showed that compound 5 exhibited weak cytotoxic activity against the HL-60 cell line.  相似文献   

11.
The new copolymers from different feed compositions of glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesized using free radical polymerization in toluene at 70±1 °C using benzoyl peroxide (BPO) as initiator. The polymers were characterized by 1H NMR, 13C NMR and FTIR spectroscopic techniques. The polydispersities of the copolymers suggest a strong tendency for chain termination by disproportionation. The glass transition temperature of the copolymers increases with increase in GMA content. The thermal stability of the copolymers increases with increase in THFA content. The copolymer compositions were determined using 1H NMR analysis. Reactivity ratios for GMA and THFA as determined by the Mao-Huglin method were r1=0.379 and r2=0.266. The results showed that all these copolymerizations are strictly linear systems describable by the Mayo-Lewis equation based on the terminal model and that accurate reactivity ratio data can be obtained.  相似文献   

12.
This paper presents the synthesis of metal complex acid dyes obtained from the reaction of o,o′-dihydroxyazo dyes and chromium and cobalt sulfate. The 1H-NMR, FT-IR and UV/Visible Spectrophotometer, TLC (Thin Layer Chromatography) and ICP (Ion Chromatography) of the intermediates and the metal complexes were studied and compared. Their properties such as dyeing, fastness and toxicity on nylon were also assessed according to standard methods.  相似文献   

13.
A new thermal conductive poly(vinylidene fluoride) (PVDF) composite has been developed via a hybrid functionalized graphene sheets (FGS)-nanodiamonds (NDs) filler by a simple solution method. The PVDF composite showed different thermal conductivities at different proportion of hybrid filler. The thermal conductivity of the composite was up to 0.66 W/m·K for a mixture containing 45 wt% hybrid filler, which is about 2-fold increment in comparison to the PVDF martrix. The PVDF composites consisting of 20 wt% hybrid FGS/ND filler at the weight ratio of 1:3 shows the best thermal stability. The electrical conductivity of composites was increased from 5.1×10?15 S cm?1 (neat PVDF) to 7.1×10?7 S cm?1 of the PVDF composite with 10 wt% hybrid filler.  相似文献   

14.
A high Mr glutenin subunit, which has not been described previously, was found in several Swedish wheat (Triticum aestivum L.) breeding lines. The electrophoretic mobility (sodium dodecyl sulphate polyacrylamide gel electrophoresis) of this band was close to the mobility of the subunit that has been referred to as band 21 encoded on chromosome 1B. Reciprocal crosses between wheat materials with and without this band have shown that the synthesis of this subunit is controlled by the locus on chromosome 1A. The new band, called 21*, is thus allelic to bands 1 and 2*. The relevance of the novel-subunit to breadmaking quality was investigated by partial-least-square regression analysis. Using this method, the relationship between the electrophoretic patterns of high Mr glutenin subunits and the specific Zeleny volume was determined. The novel glutenin subunit was found in cultivars with a high specific Zeleny volume. Further investigations are needed before it is possible to determined the influence of the new glutenin subunit on baking quality.  相似文献   

15.
Two new lipo-decapeptides, namely taeanamides A and B (1 and 2), were discovered from the Gram-positive bacterium Streptomyces sp. AMD43, which was isolated from a mudflat sample from Anmyeondo, Korea. The exact molecular masses of 1 and 2 were revealed by high-resolution mass spectrometry, and the planar structures of 1 and 2 were elucidated using NMR spectroscopy. The absolute configurations of 1 and 2 were determined using a combined analysis of 1H-1H coupling constants and ROESY correlations, the advanced Marfey’s method, and bioinformatics. The putative nonribosomal peptide synthetase pathway for the taeanamides was identified by analyzing the full genome sequence data of Streptomyces sp. AMD43. We also found that taeanamide A exhibited mild anti-tuberculosis bioactivity, whereas taeanamide B showed significant bioactivity against several cancer cell lines.  相似文献   

16.
Seven new amino alcohol compounds, pseudoaminols A–G (1–7), were isolated from the ascidian Pseudodistoma sp. collected off the coast of Chuja-do, Korea. Structures of these new compounds were determined by analysis of the spectroscopic data and from chemical conversion. The presence of an N-carboxymethyl group in two of the new compounds (6 and 7) is unprecedented among amino alcohols. Several of these compounds exhibited moderate antimicrobial activity and cytotoxicity, as well as weak inhibitory activity toward Na+/K+-ATPase.  相似文献   

17.
A high-yielding japonica rice variety, Wuyunjing 7, bred in Jiangsu Province, China as a female parent was crossed with a Japanese rice variety Kantou 194, which carries a rice stripe disease resistance gene Stv-bi and a translucent endosperm mutant gene Wx-mq. From F2 generations, a sequence characterized amplified region (SCAR) marker tightly linked with Stv-bi and a cleaved amplified polymorphic sequence (CAPS) marker for Wx-mq were used for marker-assisted selection. Finally, a new japonica rice line, Ning 9108, with excellent agronomic traits was obtained by multi-generational selection on stripe disease resistance and endosperm appearance. The utilization of the markers from genes related to rice quality and disease resistance was helpful not only for establishing a marker-assisted selection system of high-quality and disease resistance for rice but also for providing important intermediate materials and rapid selection method for good quality, disease resistance and high yield in rice breeding.  相似文献   

18.
Further purification of the apolar extracts of the sponge Plakinastrella mamillaris, afforded a new oxygenated polyketide named gracilioether K, together with the previously isolated gracilioethers E–G and gracilioethers I and J. The structure of the new compound has been elucidated by extensive NMR (1H and 13C, COSY, HSQC, HMBC, and ROESY) and ESI-MS analysis. With the exception of gracilioether F, all compounds are endowed with potent pregnane-X-receptor (PXR) agonistic activity and therefore represent a new chemotype of potential anti-inflammatory leads. Docking calculations suggested theoretical binding modes of the identified compounds, compatible with an agonistic activity on hPXR, and clarified the molecular basis of their biological activities.  相似文献   

19.
Summary The method of Vadukul (1991) for determining maleic hydrazide (MH) was modified and gave recoveries of free MH of 89%±4%. The values recorded on individual tubers ranged from 2–14 mg kg−1. Maleic hydrazide was evenly distributed throughout the tuber (peel, outer and inner flesh) but concentration increased slightly as tuber size increased. The concentration of free MH decreased from 7 to 3 mg kg−1 over the storage period of 5 1/2 months. Acid hydrolysis released substantial amounts of MH particularly from older potatoes (13 mg kg−1) compared with 6 mg kg−1 from new potatoes, implying that free MH is gradually converted to a bound form with time after treatment. No evidence was found for the presence of a β-glucoside of MH.  相似文献   

20.
为掌握黄淮南片小麦品种(系)的生产潜力,对2009-2017年度黄淮南片小麦区试参试品种(系)进行分析。结果显示:(1)黄淮南片冬麦区已初步形成科研院所和企业双主体的育种体系,9年内参试品种(系)共283个,其中教学科研单位提供的参试品种(系)155个,通过国家审定的60个,育种效率为42.27%;农业企业提供的参试品种(系)115个,通过国家审定的44个,育种效率为38.26%;(2)黄淮南片小麦育种水平逐年提高,产量稳步增加,品种改良效果明显,9年间,冬水组小麦产量增加32.84kg·667m~(-2),年均增产3.65kg·667m~(-2),春水组产量增加22.38kg·667m~(-2),年均增产2.49kg·667m~(-2);(3)育种方法上仍以传统杂交育种为主,品种遗传同质化严重,抗逆性风险加大,283个参试品种(系)和107个审定品种中,以杂交育种方法育成的分别为269个(95.05%)和102个(95.33%)。分析参试品种的系谱发现,周麦系列和百农系列亲缘系数值(COP)之和为39.82,占一级系谱COP总和的18.02%;周麦系列COP之和为20.42,占二级系谱COP总和的7.73%。  相似文献   

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