Fusarium moniliforme(F.moniliforme) and its secondary metabolite fumonisin pose a severe threat to food safety,and searching for effective antimicrobial agents is a focus of current research.In this study,the secondar...Fusarium moniliforme(F.moniliforme) and its secondary metabolite fumonisin pose a severe threat to food safety,and searching for effective antimicrobial agents is a focus of current research.In this study,the secondary structure of Sub3 was analyzed by circular dichroism,meanwhile,the inhibition rate of Sub3 against spores,mycelia of F.moniliforme and infected maize was studied.To explore the possible inhibition mechanisms,morphological and structural changes of spores treated with Sub3 at0,1/2 MIC(minimum inhibitory concentration) and MIC were observed by scanning electron microscopy and transmission electron microscopy;the cell wall integrity,membrane integrity,reactive oxygen species,mitochondrial membrane potential,ATP synthase activity,redox reactions,and the nuclear damage of F.moniliforme were also investigated.The results showed that Sub3 was mostly in the state of random in deionized water,while mainly showed the β-sheet structure in the hydrophobic environment of 50% Trifluoroethanol(TFE) solution,indicating that Sub3 might generate partial structure deformation when acting on the cell membrane;and its MIC on F.moniliforme spores was 0.2 g/L.Under the 1/2 MIC and MIC,the inhibition rates of Sub3 against F.moniliforme infected maize were 34.3% and75.6%,respectively.The results of inhibition mechanisms revealed that the defective pathogenicity of F.moniliforme caused by Sub3 was attributed to damages on both the cell wall and the cell membrane,which might upset balance of intracellular redox system and mitochondrial energy metabolism and trigger nucleus damage,ultimately leading to cell death.Meanwhile,Sub3 could diminished ATP synthase enzyme activity in a dose-dependent manner.The results provided direct evidence for inhibition of F.moniliforme infection of maize by Sub3,and useful knowledge applicable for food preservation.展开更多
The cobalt nanoparticles over γ-Al_2O_3 support were prepared via chemical reduction of CoCl_2·6H_2O using NaBH_4 with various values of pH in the range of 11. 92-13. 80. Synthesized catalysts were studied throu...The cobalt nanoparticles over γ-Al_2O_3 support were prepared via chemical reduction of CoCl_2·6H_2O using NaBH_4 with various values of pH in the range of 11. 92-13. 80. Synthesized catalysts were studied through X-ray diffraction( XRD),N_2 adsorption/desorption( BET),H_2-temperature programmed reduction( H_2-TPR),H_2-chemisorption,O_2 pulse titration and temperature programmed oxidation( TPO) methods. Obtained results exhibited the synthesis solution pH showed a significant influence on the activity and selectivity in partial oxidation of methane reaction. The methane conversion,CO selectivity and H_2 yield were enhanced by increasing of the synthesis solution pH. Compared to other catalysts,the catalyst that synthesized at pH of 13.80,showed a superior ability in syngas production with a H_2/CO ratio of near 2 and also a proper stability against deactivation during the partial oxidation of methane.展开更多
基金sponsored by grants from the Natural Science Foundation of China (31972176)the Cultivation Programme for Young Backbone Teachers in Henan University of Technology (21420114)+1 种基金the Innovative Funds Plan of Henan University of Technology (2020ZKCJ01)the National Key Research and Development Project of China(Project No.2019YFC1605303-04)
文摘Fusarium moniliforme(F.moniliforme) and its secondary metabolite fumonisin pose a severe threat to food safety,and searching for effective antimicrobial agents is a focus of current research.In this study,the secondary structure of Sub3 was analyzed by circular dichroism,meanwhile,the inhibition rate of Sub3 against spores,mycelia of F.moniliforme and infected maize was studied.To explore the possible inhibition mechanisms,morphological and structural changes of spores treated with Sub3 at0,1/2 MIC(minimum inhibitory concentration) and MIC were observed by scanning electron microscopy and transmission electron microscopy;the cell wall integrity,membrane integrity,reactive oxygen species,mitochondrial membrane potential,ATP synthase activity,redox reactions,and the nuclear damage of F.moniliforme were also investigated.The results showed that Sub3 was mostly in the state of random in deionized water,while mainly showed the β-sheet structure in the hydrophobic environment of 50% Trifluoroethanol(TFE) solution,indicating that Sub3 might generate partial structure deformation when acting on the cell membrane;and its MIC on F.moniliforme spores was 0.2 g/L.Under the 1/2 MIC and MIC,the inhibition rates of Sub3 against F.moniliforme infected maize were 34.3% and75.6%,respectively.The results of inhibition mechanisms revealed that the defective pathogenicity of F.moniliforme caused by Sub3 was attributed to damages on both the cell wall and the cell membrane,which might upset balance of intracellular redox system and mitochondrial energy metabolism and trigger nucleus damage,ultimately leading to cell death.Meanwhile,Sub3 could diminished ATP synthase enzyme activity in a dose-dependent manner.The results provided direct evidence for inhibition of F.moniliforme infection of maize by Sub3,and useful knowledge applicable for food preservation.
文摘The cobalt nanoparticles over γ-Al_2O_3 support were prepared via chemical reduction of CoCl_2·6H_2O using NaBH_4 with various values of pH in the range of 11. 92-13. 80. Synthesized catalysts were studied through X-ray diffraction( XRD),N_2 adsorption/desorption( BET),H_2-temperature programmed reduction( H_2-TPR),H_2-chemisorption,O_2 pulse titration and temperature programmed oxidation( TPO) methods. Obtained results exhibited the synthesis solution pH showed a significant influence on the activity and selectivity in partial oxidation of methane reaction. The methane conversion,CO selectivity and H_2 yield were enhanced by increasing of the synthesis solution pH. Compared to other catalysts,the catalyst that synthesized at pH of 13.80,showed a superior ability in syngas production with a H_2/CO ratio of near 2 and also a proper stability against deactivation during the partial oxidation of methane.
