Antibiotic resistant bacteria pass between humans, between animals and between humans and animals in both directions, the use of antibiotics in poultry has contributed to multiple antibiotic resistant in pathogenic ba...Antibiotic resistant bacteria pass between humans, between animals and between humans and animals in both directions, the use of antibiotics in poultry has contributed to multiple antibiotic resistant in pathogenic bacteria and use of two antibiotics might prevent the emergence of resistance to either. In this study, synergistic effect of combined antibiotics against multidrug resistant human pathogenic bacterial isolates from poultry droppings in Akure, Nigeria was examined. Collection of samples, isolation and identification of bacteria were carried out using standard microbiological method, antibiotic sensitivity test was performed by disc diffusion method and zone of inhibition was used to interpret the sensitivity test as resistant, susceptible or intermediate while combined effects of two antibiotics were investigated by macrobroth dilution and checkerboard assay methods while the synergetic effects of combined antibiotics were calculated using Fractional Inhibitory Concentration (FIC) and percentage synergistic interaction was calculated. All the ten (10) species of bacterial isolates were multidrug resistant and are less resistant to ofloxacin. The highest percentage synergistic interactions observed were Ofloxacin + Amoxicillin (90%), Ciprofloxacin + Amoxicillin (90%), Tetracycline + Amoxicillin (70%), Tetracycline + Augmentin (80%), Cotrimoxazol + Amoxicillin (50%), Cotrimoxazol + Augmentin (70%), Chloramphenicol + Amoxicillin (70%) and Chloramphenicol + Augmentin (80%). Poultry droppings is a potential source of human pathogenic bacteria, high frequency of multiple antibiotic resistance bacteria observed in this study is of great treat to man as this may cause the treatment of infection caused by these bacteria to be difficult. Combination of beta-lactam antibiotic with fluoroqunolones, tetracycline, Chloramphenicol and Cotrimoxazole was synergetic and this will reduce dose related toxicity and prevent resistance to single antibiotic.展开更多
Drought is a bottleneck for worldwide soybean production which is getting more serious as the climate continues to worsen. Dehydration responsive element binding（DREB） is a kind of transcription factor that regulate...Drought is a bottleneck for worldwide soybean production which is getting more serious as the climate continues to worsen. Dehydration responsive element binding（DREB） is a kind of transcription factor that regulates the expression of stress tolerance-related genes in response to drought, high salinity and cold stress in plant. Soybean with DREB gene possesses the drought resisting capability which is helpful to increase the yield. However, the potential risk of genetically modified plants（GMPs） on soil microbial community is still in debate. In order to understand the effects of transgenic DREB soybean on the nitrogen-fixing bacteria, the diversity of nif H gene in pot experiments planted transgenic soybean and near-isogenic nontransgenic soybean under normal water condition and drought stress condition was analyzed by PCR-DGGE and sequence analysis. The results showed that transgenic soybean under normal water condition decrease the diversity of the nitrogen-fixing bacteria in the seeding stage and flowering stage, but had no notable effect in other stages. Under drought stress, transgenic soybean reduced the diversity of the nitrogen-fixing bacteria in the flowering stage, but had no notable effects on other stages. Phylogenic analysis revealed that g7, g13, g15 and g19 had a close relationship with Alphaproteobacteria, g12 had a close relationship with Azonexus, others were related to Betaproteobacteria and Burkholderia.展开更多
Bioflocculant-producing bacteria Agrobacterium tumefaciens F2 and Bacillus sphaeicus F6 were immobilized onto mycelial pellets to investigate the bioflocculant-producing potential of this combined organism and the cor...Bioflocculant-producing bacteria Agrobacterium tumefaciens F2 and Bacillus sphaeicus F6 were immobilized onto mycelial pellets to investigate the bioflocculant-producing potential of this combined organism and the corresponding flocculating efficiency. The atomic force microscope ( AFM) images of mycelial surface indicate that the mycelia pellet can immobilize bioflocculant-producing bacteria F2 and F6 as a biomass carrier. The flocculating efficiency of bioflocculant produced by this combined organism was studied under the optimum flocculating conditions obtained by Response Surface Methodology ( RSM ) . The fermentation yield of the combined mycelial pellet is about 2. 6 g / L,which is higher than that of the free bacteria ( only 2. 2 g / L) . Flocculating efficiency of the combined mycelial pellet was comparable with that of bioflocculant generated by the free bacteria. The bioflocculant yield is enhanced and the flocculating efficiency of the co-culture is uninfluenced after immobilized with mycelial pellet as a carrier. In conclusion,the mycelial pellet is feasible as a biomass carrier for the immobilization of bioflocculant-producing bacteria.展开更多
Pneumonia is the single largest infectious cause of death in children worldwide and also a form of an acute respiratory infection that affects the lung. The purpose of the study was to develop a new approach to treat ...Pneumonia is the single largest infectious cause of death in children worldwide and also a form of an acute respiratory infection that affects the lung. The purpose of the study was to develop a new approach to treat antibiotic-resistant <i>K. pneumoniae</i> infection. This study aimed in quest of a drug to combine with ciprofloxacin, a broad spectrum antibiotic frequently used to treat lung infections. Methodology: A total of 23 lung infection bacterial samples were collected and studied against 14 antibiotics of different classes. The disk diffusion method was performed to determine synergy screening, MIC value, and qualitative toxicity analysis of ciprofloxacin and chloramphenicol combination. Results: After primary screening of antibiotic susceptibility, they were categorized into multidrug-resistant (MDR), extensively drug-resistant (XDR) and pan drug-resistant (PDR) pathogens where 9 isolates were MDR, 5 were XDR and 3 isolates were PDR. Furthermore, they were trialed in combination ciprofloxacin along with other 7 drugs in disk diffusion to explore the synergistic effect. The combination of ciprofloxacin and moxifloxacin, ciprofloxacin and chloramphenicol were found to be synergic. Then the MIC test was done for the combination ciprofloxacin and chloramphenicol. When the MIC result was generated, the MIC of the respective combination was analyzed. Furthermore, the fractional inhibitory concentration (FIC) was calculated and in accordance with the results of the FIC index, ciprofloxacin-chloramphenicol combination has shown value 0.4510 which revealed a synergistic effect against multi-drug resistant <i>Klebsiella pneumoniae</i>. Conclusion: Given these points, if the efficiency of this antibiotic can be accelerated from combination with other drugs, it might be lifesaving and cost effective as well.展开更多
文摘Antibiotic resistant bacteria pass between humans, between animals and between humans and animals in both directions, the use of antibiotics in poultry has contributed to multiple antibiotic resistant in pathogenic bacteria and use of two antibiotics might prevent the emergence of resistance to either. In this study, synergistic effect of combined antibiotics against multidrug resistant human pathogenic bacterial isolates from poultry droppings in Akure, Nigeria was examined. Collection of samples, isolation and identification of bacteria were carried out using standard microbiological method, antibiotic sensitivity test was performed by disc diffusion method and zone of inhibition was used to interpret the sensitivity test as resistant, susceptible or intermediate while combined effects of two antibiotics were investigated by macrobroth dilution and checkerboard assay methods while the synergetic effects of combined antibiotics were calculated using Fractional Inhibitory Concentration (FIC) and percentage synergistic interaction was calculated. All the ten (10) species of bacterial isolates were multidrug resistant and are less resistant to ofloxacin. The highest percentage synergistic interactions observed were Ofloxacin + Amoxicillin (90%), Ciprofloxacin + Amoxicillin (90%), Tetracycline + Amoxicillin (70%), Tetracycline + Augmentin (80%), Cotrimoxazol + Amoxicillin (50%), Cotrimoxazol + Augmentin (70%), Chloramphenicol + Amoxicillin (70%) and Chloramphenicol + Augmentin (80%). Poultry droppings is a potential source of human pathogenic bacteria, high frequency of multiple antibiotic resistance bacteria observed in this study is of great treat to man as this may cause the treatment of infection caused by these bacteria to be difficult. Combination of beta-lactam antibiotic with fluoroqunolones, tetracycline, Chloramphenicol and Cotrimoxazole was synergetic and this will reduce dose related toxicity and prevent resistance to single antibiotic.
基金Supported by the Special Scientific Fund for Non-profit Environmental Industry(2010467038)
文摘Drought is a bottleneck for worldwide soybean production which is getting more serious as the climate continues to worsen. Dehydration responsive element binding（DREB） is a kind of transcription factor that regulates the expression of stress tolerance-related genes in response to drought, high salinity and cold stress in plant. Soybean with DREB gene possesses the drought resisting capability which is helpful to increase the yield. However, the potential risk of genetically modified plants（GMPs） on soil microbial community is still in debate. In order to understand the effects of transgenic DREB soybean on the nitrogen-fixing bacteria, the diversity of nif H gene in pot experiments planted transgenic soybean and near-isogenic nontransgenic soybean under normal water condition and drought stress condition was analyzed by PCR-DGGE and sequence analysis. The results showed that transgenic soybean under normal water condition decrease the diversity of the nitrogen-fixing bacteria in the seeding stage and flowering stage, but had no notable effect in other stages. Under drought stress, transgenic soybean reduced the diversity of the nitrogen-fixing bacteria in the flowering stage, but had no notable effects on other stages. Phylogenic analysis revealed that g7, g13, g15 and g19 had a close relationship with Alphaproteobacteria, g12 had a close relationship with Azonexus, others were related to Betaproteobacteria and Burkholderia.
基金Sponsored by the National Hi-Tech Research and Development Program (Grant No. 2009AA062906)the National Creative Research Group from the National Natural Science Foundation of China (Grant No. 51121062)+1 种基金the State Key Lab of Urban Water Resource and Environment,Harbin Institute of Technology (Grant No. 2010DX09,2010TX03)the Science and Technology Development Program of Jilin Province (Grant No. 201101108)
文摘Bioflocculant-producing bacteria Agrobacterium tumefaciens F2 and Bacillus sphaeicus F6 were immobilized onto mycelial pellets to investigate the bioflocculant-producing potential of this combined organism and the corresponding flocculating efficiency. The atomic force microscope ( AFM) images of mycelial surface indicate that the mycelia pellet can immobilize bioflocculant-producing bacteria F2 and F6 as a biomass carrier. The flocculating efficiency of bioflocculant produced by this combined organism was studied under the optimum flocculating conditions obtained by Response Surface Methodology ( RSM ) . The fermentation yield of the combined mycelial pellet is about 2. 6 g / L,which is higher than that of the free bacteria ( only 2. 2 g / L) . Flocculating efficiency of the combined mycelial pellet was comparable with that of bioflocculant generated by the free bacteria. The bioflocculant yield is enhanced and the flocculating efficiency of the co-culture is uninfluenced after immobilized with mycelial pellet as a carrier. In conclusion,the mycelial pellet is feasible as a biomass carrier for the immobilization of bioflocculant-producing bacteria.
文摘Pneumonia is the single largest infectious cause of death in children worldwide and also a form of an acute respiratory infection that affects the lung. The purpose of the study was to develop a new approach to treat antibiotic-resistant <i>K. pneumoniae</i> infection. This study aimed in quest of a drug to combine with ciprofloxacin, a broad spectrum antibiotic frequently used to treat lung infections. Methodology: A total of 23 lung infection bacterial samples were collected and studied against 14 antibiotics of different classes. The disk diffusion method was performed to determine synergy screening, MIC value, and qualitative toxicity analysis of ciprofloxacin and chloramphenicol combination. Results: After primary screening of antibiotic susceptibility, they were categorized into multidrug-resistant (MDR), extensively drug-resistant (XDR) and pan drug-resistant (PDR) pathogens where 9 isolates were MDR, 5 were XDR and 3 isolates were PDR. Furthermore, they were trialed in combination ciprofloxacin along with other 7 drugs in disk diffusion to explore the synergistic effect. The combination of ciprofloxacin and moxifloxacin, ciprofloxacin and chloramphenicol were found to be synergic. Then the MIC test was done for the combination ciprofloxacin and chloramphenicol. When the MIC result was generated, the MIC of the respective combination was analyzed. Furthermore, the fractional inhibitory concentration (FIC) was calculated and in accordance with the results of the FIC index, ciprofloxacin-chloramphenicol combination has shown value 0.4510 which revealed a synergistic effect against multi-drug resistant <i>Klebsiella pneumoniae</i>. Conclusion: Given these points, if the efficiency of this antibiotic can be accelerated from combination with other drugs, it might be lifesaving and cost effective as well.
