L-半胱氨酸促进氨氮降解菌絮凝并影响其脱氮特性的机制  

MECHANISM OF L-CYSTEINE PROMOTING FLOCCULATION OF AMMONIA NITROGEN DEGRADING BACTERIA AND AFFECTING ITS DENITRIFICATION CHARACTERISTICS

作　　者：王美妮 廖金强 张佳梦 王春英[1] 潘涛[1] Wang Meini;Liao Jinqiang;Zhang Jiameng;Wang Chunying;Pan Tao(Jiangxi Province Key Laboratory of Mining and Metallurgy Environmental Pollution Control,School of Resource and Environmental Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China;College of Food Science and Technology,Nanchang University,Nanchang 330031,China)

机构地区：[1]江西理工大学资源与环境工程学院,江西省矿冶环境污染与控制重点实验室,江西赣州341000 [2]南昌大学食品学院,南昌330031

出　　处：《环境工程》2023年第S02期189-194,共6页Environmental Engineering

基　　金：国家重点研发计划课题(2019YFC1805100);国家自然科学基金(21866015);江西理工大学清江青年英才支持计划资助(JXUSTQJYX2019011)

摘　　要：为减少水处理过程中降解菌的流失,利用L-半胱氨酸促进氨氮降解菌絮凝,并探索了对氨氮去除的影响。从赣州市某污水处理厂的活性污泥中分离到9株具有较高氨氮降解效率的脱氮菌,并命名为HY1-HY9,其中HY1、HY4和HY6的降解效率较高。经16S rRNA基因序列测定与系统发育树分析确定菌株HY1为不动杆菌(Acinetobacter sp.),HY4为农杆菌(Agrobacterium sp.),HY6为假单胞菌(Pseudomonas sp.)。在此基础上,研究了L-半胱氨酸对3株菌的脱氮特性、絮凝特性、挂膜能力及细胞表面润湿性和表面活性物质分泌的影响。研究表明:HY1、HY4和HY6以丁二酸钠为碳源,L-半胱氨酸浓度为1 g/L,培养48 h后氨氮去除率分别达到90.33%、20.76%和79.57%。L-半胱氨酸能够促进HY1和HY4的菌体细胞形成稳定的絮凝体,使得细胞表面形貌发生巨大的改变。在以石英砂为填料时,1 g/L的L-半胱氨酸可以提高HY1菌液的挂膜率,增加了42.46%;但是无论L-半胱氨酸浓度为多少,细胞发酵液的表面张力均未发生显著变化,并且测量值均接近于同温下水的表面张力(72.59 N/m)。结果表明:降解菌在L-半胱氨酸存在下表现出良好的絮凝效果,其在菌体絮凝方面具有很大的应用潜力。The experiment used L-cysteine to promote the flocculation of ammonia nitrogen degrading bacteria and to explore the effect on ammonia nitrogen removal,thereby reducing the loss of degrading bacteria in the water treatment process.The experiment isolated nine strains of nitrogen removal bacteria with high ammonia nitrogen degradation efficiency from the activated sludge of a sewage treatment plant in Ganzhou City,and named them HY1-HY9,of which HY1,HY4 and HY6 had higher degradation efficiency.Analysis of 16S rRNA gene sequences with phylogenetic trees showed that the strain HY1 was Acinetobacter sp.,HY4 was Agrobacterium sp.,and HY6 was Pseudomonas sp..On this basis,the effects of L-cysteine on the denitrification characteristics,flocculation characteristics and membrane attachment ability of the three strains were studied.The analysis showed that the removel rate of HY1,HY4 and HY6 were 90.33%,20.76%and 79.57%respectively after 48 h of incubation,with sodium succinate as the carbon source and L-cysteine concentration as 1 g/L.L-cysteine can promote the formation of stable flocs in HY1 and HY4,which greatly changes the surface morphology of the cells.When using quartz sand as a filler,1 g/L of L-cysteine can improve the film attachment rate of HY1 bacteria solution,increasing by 42.46%.However,no matter what the concentration of L-cysteine is,the surface tension of cell fermentation broth has not changed significantly,and the measured values are close to the surface tension of water at the same temperature(72.59 N/m).The results showed that the degradation bacteria showed good flocculation effect in the presence of L-cysteine,indicating that it had great potential application in bacterial flocculation.

关 键 词：L-半胱氨酸 氨氮降解 絮凝 脱氮细菌 

分 类 号：X172[环境科学与工程—环境科学] X703