Quorum sensing is one kind of cell-to-cell signalling system among microorganisms that works in response to their population density via autoinducers exemplified by AHL and oligopeptides. In this study, fourteen AHL d...Quorum sensing is one kind of cell-to-cell signalling system among microorganisms that works in response to their population density via autoinducers exemplified by AHL and oligopeptides. In this study, fourteen AHL derivatives were synthesised by a chemical synthesis method, and two types of AHL derivatives were measured and screened by crystal violet staining assay, which have more obvious inhibitory effects on A. ferrooxidans biofilms under arsenic environment. Their structures were verified through IR and NMR identification. The morphological changes of A. ferrooxidans under the influence of the AHL derivatives were compared. In addition, the effects of AHL derivatives(0.1 μg/mL and 1 μg/mL) on membrane formation of A. ferrooxidans under high concentration of arsenic resistance(1,600 mg/L) were explored. Solid experimental data firstly showed that a portion of logarithmic microorganisms were ruptured under the effect of high arsenic concentration. Secondly, the volume of the cell shrank and the number of extracellular polymeric substances decreased after the addition of the AHL derivatives at high concentrations. Therefore, we found here that two derivatives used at concentrations of 0.1 μg/mL and 1 μg/m L accompanied with high concentration of arsenic can both effectively restrict biofilms formation by A. ferrooxidans.展开更多
CuO powder with microspheres,submicron sheets had been synthesized only from CuSO4 and Na2CO3 aqueous solutions by a facile route.Significant effects of initial droplet size of CuSO4 aqueous solution were observed on ...CuO powder with microspheres,submicron sheets had been synthesized only from CuSO4 and Na2CO3 aqueous solutions by a facile route.Significant effects of initial droplet size of CuSO4 aqueous solution were observed on particle size,morphology and gas sensitivity of CuO.The morphologies of CuO powder varied from microspheres to submicron sheets with the introduction method of CuSO4 to Na2CO3 aqueous solutions.Based on the characterized structure and morphology,a possible formation mechanism of CuO had been proposed.High gas sensitivity to ethanol was obtained for the CuO microspheres synthesized by spray method,which exhibited the response sensitivity of 3.25 to ethanol with the concentration of 300 ppm at 250℃.It suggests that the facile route is promising to the batch synthesis of CuO powder with good gas sensing properties.展开更多
基金Project(31660026)supported by the National Natural Science Foundation of ChinaProject(lzujbky-2016-152)supported by the National Basic Research Program of China
文摘Quorum sensing is one kind of cell-to-cell signalling system among microorganisms that works in response to their population density via autoinducers exemplified by AHL and oligopeptides. In this study, fourteen AHL derivatives were synthesised by a chemical synthesis method, and two types of AHL derivatives were measured and screened by crystal violet staining assay, which have more obvious inhibitory effects on A. ferrooxidans biofilms under arsenic environment. Their structures were verified through IR and NMR identification. The morphological changes of A. ferrooxidans under the influence of the AHL derivatives were compared. In addition, the effects of AHL derivatives(0.1 μg/mL and 1 μg/mL) on membrane formation of A. ferrooxidans under high concentration of arsenic resistance(1,600 mg/L) were explored. Solid experimental data firstly showed that a portion of logarithmic microorganisms were ruptured under the effect of high arsenic concentration. Secondly, the volume of the cell shrank and the number of extracellular polymeric substances decreased after the addition of the AHL derivatives at high concentrations. Therefore, we found here that two derivatives used at concentrations of 0.1 μg/mL and 1 μg/m L accompanied with high concentration of arsenic can both effectively restrict biofilms formation by A. ferrooxidans.
基金Supported by the National Natural Science Foundation of China(No.51602055)
文摘CuO powder with microspheres,submicron sheets had been synthesized only from CuSO4 and Na2CO3 aqueous solutions by a facile route.Significant effects of initial droplet size of CuSO4 aqueous solution were observed on particle size,morphology and gas sensitivity of CuO.The morphologies of CuO powder varied from microspheres to submicron sheets with the introduction method of CuSO4 to Na2CO3 aqueous solutions.Based on the characterized structure and morphology,a possible formation mechanism of CuO had been proposed.High gas sensitivity to ethanol was obtained for the CuO microspheres synthesized by spray method,which exhibited the response sensitivity of 3.25 to ethanol with the concentration of 300 ppm at 250℃.It suggests that the facile route is promising to the batch synthesis of CuO powder with good gas sensing properties.
