剩余污泥超声提取液培养生物破乳菌Alcaligenes sp. S- XJ-1

将超声法预处理剩余污泥得到的提取液用于培养高效生物破乳菌Alcaligenes sp. S-XJ-1,以探索剩余污泥资源化利用的新途径.使用超声能量(ES)为443~56647kJ/kg TS的超声条件处理剩余污泥,获得的污泥提取液中氨氮、有机氮、总磷的浓度最高分别为171.94,142.20, 76.29mg/L,提取液中包含K、Ca、Mg、Fe等破乳菌生长必须的金属元素.将污泥提取液(ES为885~56647kJ/kg TS)作为培养基用于合成高效破乳菌Alcaligenes sp. S-XJ-1,产量较MMSM培养基可提高0.3%~68.3%,其中ES为56647kJ/kg TS时破乳菌产量最高,为2.03g/L.污泥提取液中的pH缓冲能力对菌体产量有重要影响,提取液的有机氮浓度可能是破乳菌产量提高的关键因素.污泥提取液培养的破乳菌破乳性能稳定保持在80.0%左右,菌体细胞表面疏水性与菌体C/N较MMSM培养基培养菌体无明显差异.说明以剩余污泥超声提取液作为培养基可以培养稳定高效的破乳菌Alcaligenes sp. S-XJ-1.     

杀螺微生物的分离与杀螺及抑菌活性的研究

对中国典型培养物保藏中心的凸形假单胞菌(Pseudomonasconvexa)AB93077,AB93065和浅灰链霉菌(Streptomycesgriseolus)AA93066,AA92070,AA94037的杀螺活性进行研究表明AA92070,AA94037具有杀螺活性,其它三种菌株在本实验条件下未见杀螺活性。另外从环境中分离到一株新的具杀螺活性的链霉菌WZ,与以往报道的杀螺链霉菌不同,它的孢子丝顶端为卷曲或螺旋状。链霉菌AA92070,AA94037,WZ的发酵液经100℃处理5min后仍具有杀螺活性,这表明三种链霉菌所产生的杀螺素具有一定的耐热性。通过测定三种链霉菌发酵液的抑菌谱,可初步看出三种菌的发酵产物主要抑制细菌的生长。     

Comparing results of cultured and uncultured biological methods used in biological phosphorus removal

Increasing attention has been paid to phosphate-accumulating organisms(PAOs)for their important role in biological phosphorus removal.In this study,microbial communities of PAOs cultivated under different carbon sources(sewage,glucose,and sodium acetate) were investigated and compared through culture-dependent and culture-independent methods,respectively.The results obtained using denaturing gradient gel electrophoresis(DGGE)of polymerase chain reaction-amplified 16S rDNA fragments revealed that the diversity of bacteria in a sewage-fed reactor(1#)was much higher than in a glucose-fed one(2#)and a sodium acetate-fed one(3#);there were common PAOs in three reactors fed by different carbon sources.Five strains were separated from three systems by using a phosphate- rich medium;they were from common bacteria isolated and three isolates could not be found in DGGE profile at all.Two isolates had good phosphorus removal ability.When the microbial diversity was studied,the molecular biological method was better than the culture-dependent one.When phosphorus removal characteristics were investigated,culture-dependent approach was more effective. Thus a combination of two methods is necessary to have a comprehensive view of PAOs.     

基于缓释固体碳源的好氧反硝化复合菌NF21+FX32脱氮特性研究

从活性污泥中筛选两株好氧反硝化菌NF21和FX32,由16S r DNA基因序列分析,确定NF21为假单胞菌属(Pseudomonas),FX32为氏菌属(Bosea).以复合菌NF21+FX32为对象,通过测定菌株的生长状况和脱氮特性,研究了缓释固体碳源聚丁二酸丁二醇酯(PBS)、聚己内酯(PCL)和聚乳酸(PLA)对复合菌脱氮性能的影响.结果表明：PBS具有良好的释碳能力,60 h内的COD平均释放速率可达0.98 mg·L^-1·h^-1;复合菌NF21+FX32均可用缓释固体碳源PBS、PCL和PLA降解废水中的NO₃^--N,其中以PBS为缓释固体碳源时对NO₃^--N的去除效果最好,去除率大于85%;NF21+FX32混合培养对废水中NO₃^--N去除具有协同作用,脱氮效果好于单菌株;以PBS为缓释固体碳源时,复合菌NF21+FX32更适宜于低浓度NO₃^--N废水脱氮...