| Heavy metal and organic were main pollutants in environmental and caused a serie of environmental problems and did harm to human health that could not be ignored. Therefore, in order to achieve better protection of the environment,studied the toxicology effects mechanism of pollutants to the environment had become more importenr of many researchers. This study used of algae sensitive, short growth cycle, easier to be isolated and directly observed their poisoning symptoms and other characteristics to focuse on the Pb and phenanthrene for the toxicology experiment.Studied the changes of toxicity and mechanism of cyclodextrin and its derivatives to the Scenedesmus obliquus by single or compound pollution condition.And under alkaline conditions synthesised a new environmentally friendly materials ACD.Studied the effects of ACD to soil enzyme activity and microbial population distribution that polluted by heavy metal and organic. Laied the theroy foundation of the development of heavy metaland and organic extraction agent in contaminated soil remediation. The following main results were obtained in this study:.1: Used β-CD and aspartic acid as the raw materials,synthesized aspartate-β-CD(ACD)under alkaline conditions,and then analysised the ACD by infrared spectroscopy.Studied the effect of ACD and Pb with UV and XPS characterization and the effect of ACD and phenanthrene by fluorescence spectrum. The result showed that: ACD retained the cavity structure of β-CD. And at the same time, which had added a carboxyl and amino component that nade the interaction effect between Pb and phenanthrene.The effect of different kinds of CDs packaged phenanthrene showed :ACD> HP-β-CD>β-CD> γ-CD> α-CD.2: Selected plankton algae of Scenedesmus obliquus as test materials, the ACD as repair material, the effects of ACD on toxicities to Scenedesmus obliquuswere studied. The results showed that :with the culture time increase, the biomass of algae cells were larger than 100 mg/LACD added before.And made the conclision that ACD did not inhibit the cell growth and reproduction of Scenedesmus obliquuss cells, instead of promoting the cell growth and reproduction. Which showed that ACD didn’t harm to the environent and ACD was a kind of environmental friendly material. 3: Based on acute toxicity experiments of pollutants to Scenedesmus obliquus, the effects of cyclodextrins(CDs) and its derivatives on toxicities of individual pollution(Pb or phenanthrene) and combined pollution(Pb and phenanthrene) were studied. The results showed that under Pb or phenanthrene stress, pollutants with low concentration promoted the growth of Scenedesmus obliquus, there are good dose-effects relationships with the increase of pollutant concentration. After ACD was added, the cell density of Scenedesmus obliquus increased, however, the cell inhibition rate of Scenedesmus obliquus decreased, the 96 h EC50 of Pb to Scenedesmus obliquus changed from 0.96 mg/L to 3.79 mg/L, and the 96 h EC50 of phenanthrene to Scenedesmus obliquus changed from 40.15 μg/L to 104.38 μg/L, the toxicities of Pb and phenanthrene obviously decreased. Under the condition of combined pollution, the toxicities of Pb and phenanthrene to Scenedesmus obliquus showed a synergistic effect, and cyclodextrins(CDs) and its derivatives can obviously decrease the toxicities of combined pollution. According to inhibition effects on the toxicities of pollutants to algae cells, they were in the following order: ACD> HP-β-CD >β-CD>γ-CD>α-CD.4: Used the technology of SEM,studied the toxicities to Scenedesmus obliquus cell morphology changes under the stress of pollution(Pb, phenanthrene and combined pollution). The results showed that by normal circumstances, Scenedesmus obliquus cells showed a linear staggered arrangement, middle thick, and fine on both two sides,under the toxicities pollutants stress,the cell morphology will change and died.But after the 100 mg/L of ACD added. The surface morphology of exposured cells gradually approached to normal cells.5: The effects of ACD on the activities of urease and polyphenol oxidase and the number of microbial population in the polluted soil were studied.The result showed that urease activity was sensitive to cadmium metal, and polyphenol oxidase was sensitive to fluorene.With composite concentration of pollutant increasing, the activity of urease ranges from 0.943 to 0.151, the activity decreased 83.99%; while polyphenol oxidase activity ranges from 7.831 mg/g to 1.817 mg/g,which decreased 76.80%.The microbial population of bacteria, fungi, actinomycetes in the cadmium and fluorine pollution soil showed inhibitory effect, but the degree of inhibition was different, maximum fungal, actinomycete second and minimum bacteria, and the maximum rate was 95.27%, 78.35%, 69.54% respectively. But after adding 2% of ACD,urease activity changed from 0.94 to 1.17 and 0.15 to 0.18 and activity were increased by 24.18%, 22.52%, the activity of polyphenol oxidase changed from 7.83 mg / g to 10.21 and from 1.82 mg / g to 2.34 mg / g, the activities were increased 30.4%, 28.78% and the microbial population increased too, the number of bacteria changed from 6.04×l06cfu/g to 7.18×l06cfu/g and increased 18.87%; the number of fungi changed from 2.05×l04cfu/g to 3.24×l04cfu/g and increased 58.5%; the actinomycetes number changed from 4.25×l05cfu/g to 5.46×l05cfu/g and increased 28.47%. |
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