碳氮源对P.Fluorescens吸附和还原U(Ⅵ)的影响研究  

Effects of carbon and nitrogen source on the adsorption and reduction of U( Ⅵ) by Pseudomonas Fluorescent

作　　者：宗美荣 董发勤[2] 刘明学[2] 孙仕勇[2] 郭玉婷[2] 周青[1] 吴传龙[2] 秦永莲[1] 

机构地区：[1]西南科技大学环境与资源学院,四川绵阳621010 [2]西南科技大学固体废物处理与资源化教育部重点实验室,四川绵阳621010

出　　处：《岩石矿物学杂志》2015年第6期880-886,共7页Acta Petrologica et Mineralogica

基　　金：国家重点基础研究发展计划(2014CB846003);研究生创新基金(14cyx0034);国家自然科学基金(41272371)

摘　　要：为探讨不同碳氮源对培养基中铀酰离子的络合形态及荧光假单胞菌对铀吸附和还原作用的影响,本文以查氏培养基为基础,将蔗糖替换为葡萄糖或将硝酸钠替代为氯化铵,采用Visual MINTEQ分析研究铀酰离子络合形态。研究结果表明,碳氮源的种类对微生物生长无影响。U（Ⅵ）浓度为10 mg/L时,3种培养基中铀酰离子的主要络合形态均为UO2PO-4。U（Ⅵ）浓度为50~200 mg/L,查氏和葡萄糖碳源培养基中铀酰离子主要络合形态均为UO2（SO4）2-2。氯化铵氮源培养基中,U（Ⅵ）浓度为50 mg/L时铀酰离子的主要络合形态为UO2HPO4（aq）,浓度为100~200 mg/L时主要是UO2Cl2（aq）。荧光假单胞菌对U（Ⅵ）耐受浓度高达100 mg/L,当U（Ⅵ）浓度达到200 mg/L时,菌体失活。荧光假单胞菌为活体时,对U（Ⅵ）的吸附率为84.02%~92.59%,还原率为3.32%~10.94%,不同碳氮源对铀吸附和还原的影响较小。荧光假单胞菌为死体时,对铀的吸附率为24.33%~39.05%;非葡萄糖碳源培养基中,对铀的还原率为37.50%~44.58%,含还原性葡萄糖的培养基条件下U（Ⅵ）的还原率为53.12%。还原性葡萄糖与荧光假单胞菌对铀的还原为协同作用。荧光假单胞菌为活体时,培养基成分被微生物充分利用,两者协同作用不明显。The aim of this study is to reveal the effects of the UO22＋ complexes and P. Fluorescens on adsorption and reduction of uranium under the condition of different carbon and nitrogen sources of CZA （Czapek-Dox medium）. On the basis of the formulation of CZA, sugar was replaced by glucose and sodium nitrate was re- placed by ammonium chloride, and then the Visual MINTEQ was used to analyze the UO22 ＋ complexes. The re- sults show that different types of carbon and nitrogen sources have no effects on the growth of P. Fluorescens. There exist different types of complexes of UO22 ＋ when uranium concentration is changed. UO22＋ mainly occurs as UO2PO4- when uranium concentration is 10mg/L, and as UO2（804）22＋ when uranium concentration is 50 to 200 mg/L in CZA medium. UO2＋ exists as UO2HPO4（aq） when dextrose serves as carbon source, and as UO2Cl2（aq） when ammonium chloride serves as nitrogen source. The tolerance concentration of uranium for fluorescent pseu- domonas is higher than 100 mg/L in general, and loses its activity at 200 mg/L. Compared with live and inacti- vation of P. Fluorescens, carbon and nitrogen sources have little effects on the adsorption and reduction of urani- um. The adsorptions range from 84.02% to 92.59% and 3.32% to 10.94%, and the reduction rates range from 3.32% to 10.94% for living P. Fluorescens. The adsorption rates are 24.33% --39.05% and the reduc- tion rates are 37.50 %- 44.58% for inactivated P. Fluorescens. The reduction rate of uranium is 53.12% when glucose is used as carbon source. The results indicate that inactive bacteria and reductive glucose as carbon source synergistically reduce uranium. However, no obviously synergistically effects exist for P, Fluorescens un- der living conditions.

关 键 词：荧光假单胞菌 碳氮源 UO22+ 吸附与还原 VISUAL MINTEQ 

分 类 号：P579[天文地球—矿物学] P619.1[天文地球—地质学]