The Experts below are selected from a list of 1368 Experts worldwide ranked by ideXlab platform
Hongxun Hao - One of the best experts on this subject based on the ideXlab platform.
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Solubility and isoelectric point of Cefradine in different solvent systems
Journal of Molecular Liquids, 2020Co-Authors: Jingkang Wang, Jinyue Yang, Na Wang, Beiqian Tian, Xin Huang, Hongxun HaoAbstract:Abstract The solubility data of Cefradine in different solvent systems as a function of pH were determined by dynamic method. The effect of pH and solvent compositions on the solubility data and the isoelectric points were evaluated and discussed. It was found that the solubility data of Cefradine are consistent with the dissolution property of ampholyte, whether in mono-solvent or binary mixed solvent, which has a large solubility at large pH and small pH values and the solubility curves exhibit U shapes. The isoelectric points of Cefradine in different solvent systems were also determined and discussed. Two theoretical models were used to correlate the experimental solubility data. It was found that model I can give better correlation results.
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Determination and Correlation of Solubility of Cefradine Form I in Five Pure Solvents from (283.15 to 308.15) K
Journal of Chemical & Engineering Data, 2013Co-Authors: Yongli Wang, Chuang Xie, Guan Wang, Hongxun HaoAbstract:The solubility of Cefradine form I in five pure solvents from (283.15 to 308.15) K was experimentally determined by using an equilibrium method. It was found that the solubility of Cefradine form I in all tested solvents increased with the increase of temperature. Four thermodynamic models were used to correlate the experimental solubility data. The infinite-dilution activity coefficient and mixing properties including the mixing free Gibbs energy, enthalpy, and entropy of Cefradine form I solution were also calculated by using the nonrandom two-liquid (NRTL) model. It was found that the correlated results by the van’t Hoff equation, the modified Apelblat equation, and the NRTL model agreed well with the experimental data.
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Determination and Correlation of Solubility of Cefradine Form I in Five Pure Solvents from (283.15 to 308.15) K
2013Co-Authors: Yongli Wang, Chuang Xie, Guan Wang, Hongxun HaoAbstract:The solubility of Cefradine form I in five pure solvents from (283.15 to 308.15) K was experimentally determined by using an equilibrium method. It was found that the solubility of Cefradine form I in all tested solvents increased with the increase of temperature. Four thermodynamic models were used to correlate the experimental solubility data. The infinite-dilution activity coefficient and mixing properties including the mixing free Gibbs energy, enthalpy, and entropy of Cefradine form I solution were also calculated by using the nonrandom two-liquid (NRTL) model. It was found that the correlated results by the van’t Hoff equation, the modified Apelblat equation, and the NRTL model agreed well with the experimental data
Yan Zhou - One of the best experts on this subject based on the ideXlab platform.
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Article Combined Toxic Effects of Heavy Metals and Antibiotics on a Pseudomonas fluorescens Strain ZY2 Isolated from Swine Wastewater
2016Co-Authors: Yan Zhou, Xiao-hua ZhangAbstract:Abstract: A Pseudomonas fluorescens strain ZY2, isolated from swine wastewater, was used to investigate the synergistic effects of five heavy metals (Pb, Cu, Zn, Cr(VI) and Hg) on bacterial resistance to antibiotics. Results indicate that the combined effects of antibiotic type, heavy metal type and concentration were significant (p < 0.01). Cross-resistance to Hg and antibiotics was the most noticeable. Moreover, the resistance to Hg and Cefradine or amoxicillin, and Cr and amoxicillin were synergistic for low heavy metal concentrations, and turned antagonistic with increasing concentrations, while the resistances to Cr or Cu and Cefradine, Pb or Cu and amoxicillin, Cu and norfloxacin showed reverse effects. In addition, resistance to Zn and amoxicillin were always synergetic, while resistance to Pb and Cefradine or norfloxacin, Cr or Hg and norfloxacin as well as all the heavy metals and tetracycline were antagonistic. These results indicate that bacterial resistance to antibiotics can be affected by the type and concentration of co-exposed heavy metals and may further threaten people’s health and ecological security severely via horizontal gene transfer
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Antioxidative responses of Pseudomonas fluorescens YZ2 to simultaneous exposure of Zn and Cefradine.
Ecotoxicology (London England), 2015Co-Authors: Jin-liang Chen, Yan Zhou, Lu Huang, Shao-qi Zhou, Li-hua WenAbstract:Binary pollution of both heavy metals and antibiotics has received increasing attentions for their joint effects of eco-toxicity and health hazards. To reveal the effects of mixtures of different pollutants on bacterial antioxidant response system, Pseudomonas fluorescens ZY2, a new strain isolated from swine wastewater, was chosen to determinate growth (bacterial density OD600), reactive oxygen species (ROS) concentration, protein concentration and superoxide dismutase (SOD) activity under exposure treatments of Zn, Cefradine or Zn + Cefradine. Bacterial densities of all the treatment groups increased significantly over the incubation time, but those containing pollutant addition were slightly lower than the control at different times of incubation. Both ROS concentration and SOD activity increased first and then decreased (p < 0.01) over time, which was opposite to the protein concentrations (p < 0.01), showing a much significant increase by Cefradine alone. With Zn concentration increasing from 40 to 160 mg/L, the intracellular SOD activity increased as a response to the improvement of ROS (p < 0.05), while the balance between ROS and SOD was broken down due to the disproportionate change of total SOD activity and ROS concentration, the bacterial densities therefore decreased for the weak resistance. With the combined treatment of Zn (200 mg/L) and Cefradine (1 mg/L), though the toxicity of Zn caused a much significant increase of ROS, the bacterial resistance was further improved showing a more significant increase of total SOD activity and the bacterial densities therefore increased bacterial growth. Zn concentration also affected the protein synthesis. Either single or binary stress induced the bacterial resistance by regulating SOD activity to eliminate ROS. All results of the bacterial oxidant stress, SOD response and protein synthesis in the combined treatment groups were more complicated than those in single treatment groups, which depended on the properties of the single treatment as well as the interaction between the two treatments upon bacterial activity. For P. fluorescens ZY2, the mediation of SOD activity to eliminate ROS in response to the combined exposure to Zn and Cefradine was first revealed as one of the co-resistance mechanisms, which is informative to further understanding the risk of antibiotics resistant bacteria to human and environmental health more accurately.
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Endogenous nitric oxide in Pseudomonas fluorescens ZY2 as mediator against the combined exposure to zinc and Cefradine.
Ecotoxicology (London England), 2015Co-Authors: Yan Zhou, Jing-jing Ruan, Shao-song Huang, Li Zheng, Bao-hong Yuan, Li-hua WenAbstract:A better understanding on the mechanism involved in bacterial resistance to combined exposure to antibiotics and heavy metals is helpful in implementing practices to mitigate their ecological risk and spread of resistance genes in microbial population. Pseudomonas fluorescens ZY2, a strain isolated from swine wastewater, was chosen to study its growth (bacterial density OD600), the formation of reactive oxygen species (ROS), nitric oxide (NO) and NO synthases (NOS) under Zn, Cefradine or Zn + Cefradine treatments. Using Zn and Cefradine as representative heavy metal and antibiotic in this investigation, respectively, the resistance of P. fluorescens ZY2 to toxic chemical exposure was investigated. Bacterial densities of treatment groups significantly increased over the time of incubation, but less than the control. ROS, NO and NOS initially increased, but then decreased after the initial 8 h of culturing, and were positively related to Zn concentrations. Moreover, the formation of ROS, NOS, and NO was activated by Cefradine at Zn of up to 160 mg/L, but inhibited at Zn of 200 mg/L whether Cefradine was added or not. Zn concentration affected ROS and NO concentrations between treatments and also was closely related to the variation of the relative bacterial density. For P. fluorescens ZY2, the mediation of endogenous NO to overcome ROS in response to the combined exposure of Zn and Cefradine was suggested as a co-resistance mechanism, which would be beneficial to evaluate the ecological risk of heavy metals and antibiotics.
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Combined Toxic Effects of Heavy Metals and Antibiotics on a Pseudomonas fluorescens Strain ZY2 Isolated from Swine Wastewater
MDPI AG, 2015Co-Authors: Yan Zhou, Xiao-hua ZhangAbstract:A Pseudomonas fluorescens strain ZY2, isolated from swine wastewater, was used to investigate the synergistic effects of five heavy metals (Pb, Cu, Zn, Cr(VI) and Hg) on bacterial resistance to antibiotics. Results indicate that the combined effects of antibiotic type, heavy metal type and concentration were significant (p < 0.01). Cross-resistance to Hg and antibiotics was the most noticeable. Moreover, the resistance to Hg and Cefradine or amoxicillin, and Cr and amoxicillin were synergistic for low heavy metal concentrations, and turned antagonistic with increasing concentrations, while the resistances to Cr or Cu and Cefradine, Pb or Cu and amoxicillin, Cu and norfloxacin showed reverse effects. In addition, resistance to Zn and amoxicillin were always synergetic, while resistance to Pb and Cefradine or norfloxacin, Cr or Hg and norfloxacin as well as all the heavy metals and tetracycline were antagonistic. These results indicate that bacterial resistance to antibiotics can be affected by the type and concentration of co-exposed heavy metals and may further threaten people’s health and ecological security severely via horizontal gene transfer
Xiao-hua Zhang - One of the best experts on this subject based on the ideXlab platform.
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Article Combined Toxic Effects of Heavy Metals and Antibiotics on a Pseudomonas fluorescens Strain ZY2 Isolated from Swine Wastewater
2016Co-Authors: Yan Zhou, Xiao-hua ZhangAbstract:Abstract: A Pseudomonas fluorescens strain ZY2, isolated from swine wastewater, was used to investigate the synergistic effects of five heavy metals (Pb, Cu, Zn, Cr(VI) and Hg) on bacterial resistance to antibiotics. Results indicate that the combined effects of antibiotic type, heavy metal type and concentration were significant (p < 0.01). Cross-resistance to Hg and antibiotics was the most noticeable. Moreover, the resistance to Hg and Cefradine or amoxicillin, and Cr and amoxicillin were synergistic for low heavy metal concentrations, and turned antagonistic with increasing concentrations, while the resistances to Cr or Cu and Cefradine, Pb or Cu and amoxicillin, Cu and norfloxacin showed reverse effects. In addition, resistance to Zn and amoxicillin were always synergetic, while resistance to Pb and Cefradine or norfloxacin, Cr or Hg and norfloxacin as well as all the heavy metals and tetracycline were antagonistic. These results indicate that bacterial resistance to antibiotics can be affected by the type and concentration of co-exposed heavy metals and may further threaten people’s health and ecological security severely via horizontal gene transfer
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Combined Toxic Effects of Heavy Metals and Antibiotics on a Pseudomonas fluorescens Strain ZY2 Isolated from Swine Wastewater
MDPI AG, 2015Co-Authors: Yan Zhou, Xiao-hua ZhangAbstract:A Pseudomonas fluorescens strain ZY2, isolated from swine wastewater, was used to investigate the synergistic effects of five heavy metals (Pb, Cu, Zn, Cr(VI) and Hg) on bacterial resistance to antibiotics. Results indicate that the combined effects of antibiotic type, heavy metal type and concentration were significant (p < 0.01). Cross-resistance to Hg and antibiotics was the most noticeable. Moreover, the resistance to Hg and Cefradine or amoxicillin, and Cr and amoxicillin were synergistic for low heavy metal concentrations, and turned antagonistic with increasing concentrations, while the resistances to Cr or Cu and Cefradine, Pb or Cu and amoxicillin, Cu and norfloxacin showed reverse effects. In addition, resistance to Zn and amoxicillin were always synergetic, while resistance to Pb and Cefradine or norfloxacin, Cr or Hg and norfloxacin as well as all the heavy metals and tetracycline were antagonistic. These results indicate that bacterial resistance to antibiotics can be affected by the type and concentration of co-exposed heavy metals and may further threaten people’s health and ecological security severely via horizontal gene transfer
Ruixin Guo - One of the best experts on this subject based on the ideXlab platform.
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The concentration of Cefradine in the first and second treatment batches.
2015Co-Authors: Jianqiu Chen, Fengzhu Zheng, Ruixin GuoAbstract:The concentration of Cefradine in the first and second treatment batches.
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Adsorption of Cefradine onto Powder and Activated Carbon Prepared from Orange Peel
Applied Mechanics and Materials, 2013Co-Authors: Ruixin Guo, Zhi Liang Wang, Jianqiu ChenAbstract:The adsorption of Cefradine was carried out using biological adsorbents of powder and carbon prepared from orange peels, an agriculture by-product. The equilibrium was easily reached in less than 10 minutes, with adsorption rates of more than 98%. Cefradine showed a firm combination to the adsorbent, which could hardly be damaged or affected by pH values. After equilibrium was reached within 1 h, no desorption behavior was observed in the next 30 minutes. The adsorption process could be well fitted thermodynamically to both Freundlich and Langmuir equations. Similar results could also be obtained using ashes of orange peel, as well as carbon prepared from pistachio and peanut hull, indicating an attractive option to treat industrial wastewater.
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Access the toxic effect of the antibiotic Cefradine and its UV light degradation products on two freshwater algae.
Journal of Hazardous Materials, 2012Co-Authors: J.q. Chen, Ruixin GuoAbstract:Two common freshwater algae Microcystis aeruginosa and Scenedesmus obliquus were employed as test organism to evaluate the toxic effects of the widely used antibiotic, Cefradine. In general, Cefradine had significantly toxic effect on population growth and chlorophyll-a accumulation of two algae and the cyanophyceae was more sensitive than the chlorophyceae. In addition, Cefradine UV light degraded products had adverse effect on M. aeruginosa's growth and chlorophyll-a accumulation. In comparison, even if S. obliquus had growth ability when exposed to Cefradine UV light-degradation products, the algal photosynthesis function was also disrupted.
Jingkang Wang - One of the best experts on this subject based on the ideXlab platform.
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Solubility and isoelectric point of Cefradine in different solvent systems
Journal of Molecular Liquids, 2020Co-Authors: Jingkang Wang, Jinyue Yang, Na Wang, Beiqian Tian, Xin Huang, Hongxun HaoAbstract:Abstract The solubility data of Cefradine in different solvent systems as a function of pH were determined by dynamic method. The effect of pH and solvent compositions on the solubility data and the isoelectric points were evaluated and discussed. It was found that the solubility data of Cefradine are consistent with the dissolution property of ampholyte, whether in mono-solvent or binary mixed solvent, which has a large solubility at large pH and small pH values and the solubility curves exhibit U shapes. The isoelectric points of Cefradine in different solvent systems were also determined and discussed. Two theoretical models were used to correlate the experimental solubility data. It was found that model I can give better correlation results.