The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion w...The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion were also studied here. The results indicated that the UV maximum absorption wavelength of the inclusion remained at 223 nm, while its intensity decreased. The XRD peaks of atrazine disappeared, weakened and shifted in the inclusion, and the chemical shift of H-3 and H-5 of cyclodextrin inner cavity led to the upfield. The characterization data showed that the atrazine-HPCD inclusion had already formed. At the same time, the solubility of the atrazineHPCD inclusion in water became 20.08 times as that of atrazine. Moreover, the atrazine-HPCD inclusion had better herbicidal activity. When the concentration of the inclusion was 6.5 mg/mL, the inhibition ratios of the inclusion to taproot length, taproot fresh weight, sprout length and sprout fresh weight of barnyard grass were 66.96%, 57.22%, 70% and 57.53%, respectively, which were all higher than those of atrazine.展开更多
The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great concern.The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability.Enhanced biode...The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great concern.The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability.Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized.However,the quantitative relationship concerning the impact of solids was rarely reported.A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin(HPCD)into a mixture of phenanthrene solution and various glass beads(GB37-63,GB105-125,and GB350-500).The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium.A model was proposed to describe the biodegradation process.The regression results indicated that the partition coefficient kd(1.234,0.726 and 0.448 L·g–1)and the degradation rate k(0 mmol·L^(–1):0.055,0.094,and 0.112;20 mmol·L^(–1):0.126,0.141,and 0.156;40 mmol·L^(–1):0.141,0.156 and 0.184 d^(–1))were positively and negatively correlated with the calculated total surface area(TSA)of solids,respectively.Degradation enhanced in the presence of HPCD,and the enhancing factor f was calculated(20 mmol·L^(–1):15.16,40.01,and 145.5;40 mmol·L^(–1):13.29,37.97,and 138.4),indicating that the impact of solids was significant for the enhancement of biodegradation.展开更多
基金Supported by the National Natural Science Foundation of China(No.31370709)
文摘The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion were also studied here. The results indicated that the UV maximum absorption wavelength of the inclusion remained at 223 nm, while its intensity decreased. The XRD peaks of atrazine disappeared, weakened and shifted in the inclusion, and the chemical shift of H-3 and H-5 of cyclodextrin inner cavity led to the upfield. The characterization data showed that the atrazine-HPCD inclusion had already formed. At the same time, the solubility of the atrazineHPCD inclusion in water became 20.08 times as that of atrazine. Moreover, the atrazine-HPCD inclusion had better herbicidal activity. When the concentration of the inclusion was 6.5 mg/mL, the inhibition ratios of the inclusion to taproot length, taproot fresh weight, sprout length and sprout fresh weight of barnyard grass were 66.96%, 57.22%, 70% and 57.53%, respectively, which were all higher than those of atrazine.
文摘The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great concern.The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability.Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized.However,the quantitative relationship concerning the impact of solids was rarely reported.A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin(HPCD)into a mixture of phenanthrene solution and various glass beads(GB37-63,GB105-125,and GB350-500).The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium.A model was proposed to describe the biodegradation process.The regression results indicated that the partition coefficient kd(1.234,0.726 and 0.448 L·g–1)and the degradation rate k(0 mmol·L^(–1):0.055,0.094,and 0.112;20 mmol·L^(–1):0.126,0.141,and 0.156;40 mmol·L^(–1):0.141,0.156 and 0.184 d^(–1))were positively and negatively correlated with the calculated total surface area(TSA)of solids,respectively.Degradation enhanced in the presence of HPCD,and the enhancing factor f was calculated(20 mmol·L^(–1):15.16,40.01,and 145.5;40 mmol·L^(–1):13.29,37.97,and 138.4),indicating that the impact of solids was significant for the enhancement of biodegradation.
