摘要
以筛选分离得到的好氧反硝化菌HG-7为研究对象,经过16SrRNA同源性分析,初步鉴定该菌株为假单胞菌属(Pseudomonassp.)。对菌株HG-7反硝化功能基因的扩增结果表明,菌体HG-7内存在好氧反硝化功能基因napA和nirK,证实该细菌为好氧反硝化细菌。对菌株的脱氮特性和影响因素的研究表明,以硝酸盐氮为氮源时,菌株的最适碳源为乙酸钠和丁二酸钠,最佳C/N比为6~10,最适宜的温度范围为26~30℃。在上述条件下,菌株HG-7的好氧反硝化活性较高,48小时内对100 mg/L硝酸盐氮的去除率可达98%,且在反应过程中亚硝酸盐氮积累量较低。以亚硝酸氮为唯一氮源时,低浓度条件下可实现100%的氮素去除率;高浓度条件下,脱氮速率则受到明显的抑制,对91.4 mg/L的亚硝酸盐氮氮去除率约为40%。因此,将该菌株应用于废水的脱氮处理,可实现氮素的有效去除,具有潜在的应用价值。
Strain HG-7 was identified as Pseudomonas sp.through 16 s rRNA gene sequence analysis.The aerobic denitrification ability of strain HG-7 was further proved by the existence of the napA and nirK genes.Further studies showed that the optimal carbon resources for strain HG-7 were sodium acetate and sodium succinate,the optimal C/N ratio was 6-10,and the suitable temperature was 26-30℃.At this condition,with an initial nitrate nitrogen of 100 mg/L,98% of nitrate could be removed in 48 hours and the amount of nitrite accumulation was very small.Moreover,with nitrite as the sole nitrogen source,100% of nitrite could be removed at lower nitrite concentration.But the nitrite nitrogen removal rate was about 40% when the nitrite concentration increased to 91.4 mg/L,indicating that high nitrite concentration was harmful for aerobic denitrification by strain HG-7.The strain HG-7 has great potential to be used for biological nitrogen removal,which was particularly significant for actual wastewater treatment processes.
引文
[1]Padhi S K,Tripathy S,Sen R,et al.Characterisation of heterotrophic nitrifying and aerobic denitrifying Klebsiella pneumoniae CF-S9 strain for bioremediation of wastewater.International Biodeterioration&Biodegradation,2013,78(3):67-73
[2]孙庆花,于德爽,张培玉,等.1株海洋异养硝化-好氧反硝化菌的分离鉴定及其脱氮特性.环境科学,2016,37(2):647-654
[3]Huang X F,Li W G,Zhang D Y,et al.Ammonium removal by a novel oligotrophic Acinetobacter sp.Y16 capable of heterotrophic nitrification-aerobic denitrification at low temperature.Bioresource Technology,2013,146(10):44-50
[4]王静,丁国际,林玮,等.Acinetobacter baumannii WJ6茵落的生长及其异养硝化一好氧反硝化特性.净水技术,2016,35(1):67-69
[5]张培玉,曲洋,于德爽,等.菌株qy37的异养硝化/好氧反硝化机制比较及氨氮加速降解特性研究.环境科学,2010,31(8):1819-1826
[6]肖继波,江惠霞,褚淑祎.不同氮源下好氧反硝化菌Defluvibacter lusatiensis str.DN7的脱氮特性.生态学报,2012,32(20):6463-6470
[7]赵惊鸿,黄少斌.一株耐高温好氧反硝化菌的筛选及特性研究.环境科学与技术,2015,38(1):6-10
[8]Chen Q,Ni J R.Ammonium removal by Agrobacterium sp.LAD9 capable of heterotrophic nitrificationaerobic denitrification.Journal of Bioscience and Bioengineering,2012,113(5):619-623
[9]中华人民共和国环境保护总局.HJ/T 346-2007水质硝酸盐氮的测定紫外分光光度法(试行).北京:中国环境科学出版社,2007
[10]中华人民共和国国家环境保护局.GB 7493-1987水质亚硝酸盐氮的测定分光光度法.北京:中国标准出版社,1987
[11]张倩,王弘宇,桑稳姣,等.1株反硝化除磷菌的鉴定及其反硝化功能基因研究.环境科学学报,2013,34(7):2876-2881
[12]Bernat K,Wojnowska-Barya I.Carbon source in aerobic denitrification.Biochemical Engineering Journal,2007,36(2):116-122
[13]Her J J,Huang J S.Influences of carbon source and C/N ratio on nitrate/nitrate denitrificationand carbon breakthrough.Bioresource Technology,1995,95(54):45-51
[14]Richardson D J,Ferguson S J.The influence of carbon substrate on the activity of the periplasmic nitrate reductase in aerobically grown Thiosphaera pantotropha.Archives of Microbiology,1992,157(6):535-537
[15]姜磊,徐成斌,马溪平,等.1株好氧反硝化菌的分离鉴定和反硝化特性研究.环境科学与技术,2013,36(3):12-15
[16]陈玲,白洁,赵阳国,等.分离于河口区芦苇湿地1株好氧反硝化菌的鉴定及其反硝化特性.微生物学报,2016,56(8):1314-1325
[17]刘天琪,金若菲,周集体,等.异养硝化-好氧反硝化菌ADN-42的脱氮特性.环境工程学报,2015,9(2):889-996
[18]Zheng H Y,Liu Y,Gao X Y,et al.Characterization of a marine origin aerobic nitrifying-denitrifying bacterium.Journal of Bioscience&Bioengineering,2012,114(1):33-37
[19]王弘宇,马放,苏俊峰,等.好氧反硝化菌株的鉴定及其反硝化特性研究.环境科学,2007,28(7):1548-1552
[20]赵丹,于德爽,李津,等.菌株ZD8的分离鉴定及其异养硝化和缺氧/好氧反硝化特性研究.环境科学学报,2013,33(11):3007-3016
[21]田雪雪,程玉立,张圆圆,等.一株异养硝化-好氧反硝化功能菌的分离鉴定及其脱氮特性.环境工程学报,2017,11(2):1269-1275
[22]Rodriguez-Caballero A,Hallin S,Pahlson C,et al.Ammonia oxidizing bacterial communitycomposition and process performance in wastewater treatment plants under low temperature conditions.Water Science&Technology,2012,66(2):197-204
[23]Joo H S,Hirai M,Shoda M.Characteristics of ammonium removal by heterotrophic nitrificationaerobic denitrification by Alcaligenes faecalis No.4.Journal of Bioscience&Bioengineering,2005,100(4):184-191
[24]Ren Y X,Yang L,Liang X.The characteristics of a novel heterotropic nitrifying and aerobic denitrifying bacterium,Acinetobacter junii YB.Bioresource Technology,2014,171:1-9
[25]Yao S,Ni J R,Ma T,et al.Heterotrophic nitrification and aerobic denitrification at low temperature by a newly isolated bacterium,Acinetobacter sp.HA2.Bioresource Technology.2013,139:80-86
[26]Song Z F,An J,Fu G H,et al.Isolation and characterization of an aerobic denitrifying Bacillus sp.YX-6from shrimp culture ponds.Aquaculture,2011,319(1/2):188-193