| Cadmium is a toxic heavy metal which has high value of application. Accordingly, because of its wide utilization, cadmium always causes very serious pollution. Generally, cadmium polluted area contains plenty of cadmium-resistant microbial population. Therefore it is profoundly significant to screen highly cadmium-resistant bacteria and do research on it. The research mainly contains the abilities and mechanism of resistance against cadmium, cadmium adsorption and accumulation of those bacteria in polluted areas. Furthermore, due to complex composition of pollutants which leads to associated and integrated pollution in real environment, combined pollution of organic matter and heavy mental is supposed to be focused as well. In this paper, the abilities of resistance against cadmium, cadmium adsorption and accumulation of selected bacteria are demonstrated with experiment. Moreover, what need to be mentioned is the result also shows that the bacteria perform well on phenol degradation after domestication so that further research has focused on this characteristic.In this paper, a cadmium-resistant bacterial strain, DX-T3-01, was isolated from tailing dam of De Xing Copper Mine, Jiangxi Province. According to its morphological, physiological characteristics, BIOLOG identification and the analysis of its 16S rRNA sequence, it was identified as a strain of Ralstonia pickettii. The strain could be tolerate to 18 mmol/L Cd2+ on solid medium and 16 mmol/L Cd2+ in liquid medium, which indicated it had high resistance to cadmium. The strain also has a high resistance of Zn2+ (20 mmol/L), Cu2+ (3 mmol/L), penicillin (1500 mg/L) and streptomycin (250 mg/L). Its optimum growth and cadmium-resistance conditions were:temperature 35℃, pH 7.0, shaking speed 150 r/min and glucose as carbon source. This paper studies cadmium accumulation of mature bacteria and freeze-dried bacteria. Most accumulation happens during stable growth, which means accumulation depends on proliferation of bacteria cell mostly. Optimum conditions of the accumulation are 40℃, PH 30, adsorption amounts to 80% in 30 minutes, adsorption tends to saturation and the adsorption process complies with second order rate equation. The differences before and after cadmium precipitation outside the cell were studied with scanning electron microscopy-energy dispersive spectroscopy (SEM-EDX), and the accumulation to Cd2+ in the strain was observed by infrared spectroscopy (FTIR). SEM-EDX shows that there was much granular cadmium precipitate on the cell wall. FTIR indicated the possible functional groups on the cell wall during the accumulation of Cd2+ were-PO43-,-C-N-,-M-O(O-M-O), C=O,-CO-NH-groups.Ralstonia pickettii strain DX-T3-01 was identified to have phenol-degrading capability by acclimation. The optimum phenol-degrading conditions were obtained by orthogonal experiment, which are 30℃, pH 7.0,150 r/min, and 1% (Ⅴ/Ⅴ). The effects of glucose as carbon source and heavy metal on phenol-degrading were discussed. Under the best conditions for degradation, phenol with initial concentration of 500 mg/L could be degraded completely in 56 hours, and 800 mg/L was the maximum degradation concentration. The kinetics of phenol degradation between 300 mg/L and 600 mg/L were preliminary studied with the Monod model zero-order reaction. The theoretical and experimental values fit preferably, and the model can well explain the experimental phenomena.
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