【作者】 叶丙静；

【导师】 方建；

【作者基本信息】 兰州大学 ， 物理化学， 2008， 硕士

【摘要】 生物热化学是从能量角度对生命现象进行实验研究和理论解释的科学,而微量热是生物热化学研究的重要方法之一。微量热由于其本身特有的高灵敏、自动化等优点,已经在生命科学、环境科学、土壤学等众多领域取得了广泛的应用。本论文通过TAM-2277热活性检测仪,采用停流法研究了AlCl₃、CaCl₂对大肠杆菌代谢活性的影响以及AlCl₃和CaCl₂对大肠杆菌的联合作用;安瓿法研究了平凉土壤、青藏高原冻土微生物的代谢活性。论文主要包括以下内容:1.使用停流法分别研究了AlCl₃、CaCl₂对大肠杆菌生长代谢的影响,以及AlCl₃和CaCl₂对大肠杆菌的联合作用。研究发现,AlCl₃对大肠杆菌生长具有抑制作用,作用机理取决于AlCl₃溶液中三价铝的具体存在形态;CaCl₂在低浓度时对大肠杆菌生长代谢具有促进作用,而高浓度时具有抑制作用;AlCl₃和CaCl₂同时作用时,对大肠杆菌生长代谢的影响的机理更为复杂,即存在协同作用,也存在拮抗作用,具体表现主要取决于两者的浓度。微量热法关于这两种化合物对大肠杆菌代谢的影响的研究尚未见文献报道。2.使用安瓿法研究了不同保存温度对平凉土壤微生物活性的影响。实验结果表明,保存温度在-20℃～25℃范围内,土壤微生物产热速率及对数期生长速率等与保存温度呈正相关;但是在4℃产热最高,说明该温度保存的土壤微生物具有最高活性。微量热法研究保存温度对土壤微生物活性的影响尚未见文献报道。3.使用安瓿法研究了青藏高原不同植被覆盖及不同退化程度冻土土样微生物活性的差异。实验研究表明,相同植被覆盖下的冻土微生物的热谱图形状相似,说明其微生物结构相似;冻土中的微生物代谢活性相比较于普通土壤要小的多。微生物数量与总热呈正相关,植被退化越严重,冻土中微生物数量越少,产热也越低。用微量热法对青藏高原冻土微生物活性及微生物活性与植被关系的研究尚未见报道。更多还原

【Abstract】 The biothemochemistry is an art of observation, identification, description, experimental investigation, and theoretical explanation of biological phenomena in the view of energy. Calorimetry is the most important tools in the fields of biothermochemistry. Microcalorimetry as a new kind of techniques has been widely used in life sciences, environmental sciences,clinical medicine and agrology for its advantages of high sensitivity, automability. The main interest in this research work was focused on metabolic characteristics of microbes. By using TAM-2277 Thermal Activity Monitor, we have studied the effects of the AlCl₃, CaCl₂ and the associated action of AlCl₃ and CaCl₂ on E.coli（DH5α） metabolic activity by the stopped-flow method, and studied the soil microbial metabolic activity by the ampoule method. The main research includes:1. The effects of AlCl₃, CaCl₂ and the associated action of AlCl₃ and CaCl₂ on the metabolic activity of E. coli（DH5α） were studied by the stopped-flow method. The experimental results show that the inhibitory effect of AlCl₃ on the growth metabolism of E.coli（DH5α）, and the mechanism depends on the species of Al（III） in the solution; CaCl₂ has a stimulatory effect on the growth of E.coli（DH5α） at the low concentration, while inhibit at the high concentration; when the two compounds affect E.coli（DH5α） simultaneously, the mechanism is complicated, namely, there are antagonistic or cooperative interaction between AlCl₃ and CaCl₂. This depend on the relative concentrations of AlCl₃ and CaCl₂. It has not been reported that the microcalorimetry method study the effects of the two compounds on the metabolic activity of E.coli.2. The effects of different preserved temperatures on the microorganism activity of the Pingliang soil were studied by the ampoule method. Experimental results show that the heat production rate and the growth rate of the log phase of the soil microoganisms have a positive correlation with the preserved temperature from -20℃to 25℃. But there are the highest total heat production at 4℃, which shows that the soil microbial have the highest activity at this preserved temperature. The effects of preserved temperatures on the microorganism activity of the soil have not been reported previousely by microcalorimetry method.3. The differences of the microbial activity between the permafrost soil samples of different vegetation coverage and degradation in different degree in Tibetan Plateau were studied by the ampoule method. Experimental studies show that the structures of the permofrost microbial and thermal spectra shape of the frozen soils are similar under the same vegetation coverage and the total number of microorganisms is positive correlation with the total heat production, but the frozen soil microbial metabolic activity is small campared to ordinary soil. The more serious degradation degradation of vegetation, the fewer the number of the microbial of permafrost soils, and the lower heat production. The research about the activity of permafrost and the relation between the microbial and the vegetation coverage have not been reported previously by microcalorimetry method.更多还原