【作者】 钱伟；

【导师】 陈盛；

【作者基本信息】 福建师范大学 ， 物理化学， 2004， 硕士

【摘要】 微生物絮凝剂是天然高分子絮凝剂的重要种类。它具有无毒、无二次污染的显著特点，而且在絮凝沉降的同时还具有可生化降解等功能。产絮凝剂的微生物种类多，生长快，易于采取生物方法实现产业化，具有广阔的发展前途。 从福州郊区地表土壤中分离得到一株絮凝剂产生菌，其菌落具有表面光滑、呈透明的蛋清状、形状较大的特点。筛选结果表明：从产荚膜微生物的菌落形态来初步筛选、分离絮凝剂产生菌的方法是可行性的，并具有快速和简便的优点。同时也证明荚膜与微生物絮凝活性存在一定的联系。微生物鉴定结果为链球菌属。 在实验室条件下确立了该菌株的发酵培养基组成和最适摇瓶发酵条件及絮凝剂使用的实验室最佳条件。对高岭土的絮凝实验研究表明：金属阳离子能影响絮凝剂的絮凝活性。结合离子形态、特性和有机高分子絮凝的化学模型，初步分析了该种微生物絮凝剂可能的絮凝机理。 对发酵获得的絮凝活性物质进行了分离和提取。应用DEAE-Sephadex A25，Sephdarose 4B凝胶色谱柱从发酵液中提取活性物质并纯化。通过TLC、GC、UV、IR、元素分析等表征后初步推测了其主要成分为酸性多糖，其中多糖含量（73％）、糖醛酸含量（20.6％）、多糖分子量为1.0×10^5.63Da，可能还有少量氨基或短肽结构。 应用该絮凝剂处理南安市某石板材厂废水，结果表明：微生物絮凝剂能有效去除石材废水中的固体颗粒悬浮物。在废水处理过程中少量Ca²⁺和搅拌能有效降低出水的浊度，去除率可达83％。更多还原

【Abstract】 Bioflocculant is an important sort of the macromolecular flocculants. It has such advantages: no toxicity, no pollution. Bioflocculant produced by microorganism can be easy to achieve industrialization through biology engineering and biodecomposed.The microorganism that can produce bioflocculant was screened by conventional method from the soil. One streptococcus strain possess capsule was separated completely. The result indicates: the method observing the community shapes was simple and convenient for screening flocculants producing microorganisms.The studies were focused on the optimum culture medium, culture conditions and apply conditions. The investigation of flocculating the alkaline kaolin suspensions suggests that metal ions can affect the flocculate rate distinctly. A likely model was put forward based on experiment phenomena.Ethanol and Sevag precipitated the bioflocculant that was purified to homogeneity through Sephadex-DEAE A-25 and Sepharose 4B gel chromatogram columns. The results suggested the effective component in bioflocculant was polysaccharide characterized by TLC GC UV IR and elemental analysis. The biopolymer contained sugar (73%) and uronic acid (20.6%), elemental analysis suggested little amdio and peptide might exist. The molecular weight measured by HPLC was 1.0 X 105.63Da.The flocculation effect, SS was removed distinctly; of bioflocculant on the treatment of lapis waste water was observed. Turbidity analysis indicated additional Ca2+ and agitation would improve the water quality. Turbidity Removal efficiency is up to 83%.更多还原