Four hydroxybenzoic acid building blocks, m-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxyterephthalic acid, and 5-hydroxyisophthalic acid, have been synthesized as robust cocrystallizing agents and emp...Four hydroxybenzoic acid building blocks, m-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxyterephthalic acid, and 5-hydroxyisophthalic acid, have been synthesized as robust cocrystallizing agents and employed in reactions with piperazine, including [(C4H12N2 2+).(C7H5O3-)2] (l), [(CaH12N2 2+).(C7H5O4-)2] (2), [(C4H12N2 2+).(C8H5O6 2- )] (3), and [(C4H12N2 2+)1/2. (C8H5O5)] . 2H2O (4). Hydrogen-bonded directed assemblies of four salts were validated by single-crystal X-ray diffraction analysis. In compounds 1-4, hydroxybenzoic acids are all deprotonated and piperazine molecules are all protonated to form piperazine dications and keep the chair conformation. Thermal stability of these compounds has been investigated.展开更多
Polycyclic aromatic hydrocarbons (PAHs) in soil retain for a quite long period due to their hydrophobicity and aggregation properties. Biofilm-forming marine bacterial consortium (named as NCPR), composed of Steno...Polycyclic aromatic hydrocarbons (PAHs) in soil retain for a quite long period due to their hydrophobicity and aggregation properties. Biofilm-forming marine bacterial consortium (named as NCPR), composed of Stenotrophomonas acidaminiphila NCW702, Alcaligenes faecalis NCW402, Pseudomonas mendocina NR802, Pseudornonas aeruginosa N6P6, and Pseudomonas pseudoalcaligenes NP103, was used for the bioremediation of PAHs in a soil microcosm. Phenanthrene and pyrene were used as reference PAHs. Parameters that can affect PAH degradation, such as chemotaxis, solubility of PAHs in extracellular polymeric substances (EPS), and catechol 2,3-dioxygenase (C230) activity, were evaluated. P. aeruginosa N6P6 and P. pseudoalcaligenes NP103 showed chemotactic movement towards both the reference PAHs. The solubility of both the PAHs was increased with an increase in EPS concentration (extracted from all the 5 selected isolates). Significantly (P 〈 0.001) high phenanthrene (70.29%) and pyrene (55.54%) degradation was observed in the bioaugmented soil microcosm. The C230 enzyme activity was significantly (P 〈 0.05) higher in the bioaugmented soil mi- crocosm with phenanthrene added at 173.26 ± 2.06 nmol rain-1 mg-1 protein than with pyrene added at 61.80 ± 2.20 nmol min-1 mg-1 protein. The C230 activity and gas chromatography-mass spectrometer analyses indicated catechol pathway of phenanthrene metabolism. However, the metabolites obtained from the soil microcosm added with pyrene revealed both the catechol and phthalate pathways for pyrene degradation.展开更多
基金supported by the National Natural Science Foundation of China (20701023,20971076)the Natural Science Foundation of Shandong Province,China (BS2010NJ004,2009ZRB019KH)
文摘Four hydroxybenzoic acid building blocks, m-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxyterephthalic acid, and 5-hydroxyisophthalic acid, have been synthesized as robust cocrystallizing agents and employed in reactions with piperazine, including [(C4H12N2 2+).(C7H5O3-)2] (l), [(CaH12N2 2+).(C7H5O4-)2] (2), [(C4H12N2 2+).(C8H5O6 2- )] (3), and [(C4H12N2 2+)1/2. (C8H5O5)] . 2H2O (4). Hydrogen-bonded directed assemblies of four salts were validated by single-crystal X-ray diffraction analysis. In compounds 1-4, hydroxybenzoic acids are all deprotonated and piperazine molecules are all protonated to form piperazine dications and keep the chair conformation. Thermal stability of these compounds has been investigated.
基金supported in part by the Department of Biotechnology, Ministry of Science and Technology, Government of India (No. BT/PR14998/GBD/ 27/279/2010)
文摘Polycyclic aromatic hydrocarbons (PAHs) in soil retain for a quite long period due to their hydrophobicity and aggregation properties. Biofilm-forming marine bacterial consortium (named as NCPR), composed of Stenotrophomonas acidaminiphila NCW702, Alcaligenes faecalis NCW402, Pseudomonas mendocina NR802, Pseudornonas aeruginosa N6P6, and Pseudomonas pseudoalcaligenes NP103, was used for the bioremediation of PAHs in a soil microcosm. Phenanthrene and pyrene were used as reference PAHs. Parameters that can affect PAH degradation, such as chemotaxis, solubility of PAHs in extracellular polymeric substances (EPS), and catechol 2,3-dioxygenase (C230) activity, were evaluated. P. aeruginosa N6P6 and P. pseudoalcaligenes NP103 showed chemotactic movement towards both the reference PAHs. The solubility of both the PAHs was increased with an increase in EPS concentration (extracted from all the 5 selected isolates). Significantly (P 〈 0.001) high phenanthrene (70.29%) and pyrene (55.54%) degradation was observed in the bioaugmented soil microcosm. The C230 enzyme activity was significantly (P 〈 0.05) higher in the bioaugmented soil mi- crocosm with phenanthrene added at 173.26 ± 2.06 nmol rain-1 mg-1 protein than with pyrene added at 61.80 ± 2.20 nmol min-1 mg-1 protein. The C230 activity and gas chromatography-mass spectrometer analyses indicated catechol pathway of phenanthrene metabolism. However, the metabolites obtained from the soil microcosm added with pyrene revealed both the catechol and phthalate pathways for pyrene degradation.