摘要
亚硝酸盐具有一定的生理毒害作用,适于高浓度亚硝酸盐氮脱除的反硝化细菌的筛选及其性能研究对于废水处理具有重要意义。通过富集培养、平板初筛、摇瓶复筛从水产养殖厂废水中筛选反硝化细菌,经生理生化和 16S rRNA 分子生物学鉴定,确定菌株的种属;对碳源种类、亚硝酸盐浓度、pH、装液量、接种量、种龄、温度等因素对菌株降解亚硝酸盐的影响进行研究,提高菌株脱除亚硝酸盐氮的效率。鉴定结果所筛选菌株 Y7 隶属于芽孢杆菌属,将其命名为 Bacillus subtilis Y7。单因素优化的结果为:以甘油为最适碳源、起始 pH 7.0、250 mL 三角瓶中装液量 100 mL、种龄 24 h 且菌液(OD600=1.5)的接种量为 10%、在 30℃条件下 170 r/min 发酵培养 24 h 后,菌株 Y7 对 1 100 mg/L 亚硝酸盐的降解率达到 100%。菌株 Y7 不仅耐受高达 1 100 mg/L 的亚硝酸盐,而且 50℃的高温也不影响其降解亚硝酸盐的效率。菌株 Y7 适合处理含高浓度亚硝酸盐的高温工业废水及夏季的水产养殖废水。
Due to the toxic effect of nitrite,the screening and denitrification characteristics of denitrifying bacteria suitable for removing high-concentration nitrite-nitrogen are of great significance. Enrichment culturing,preliminary screening with plates and secondary screening with flasks were used to screen denitrifying bacteria from aquaculture wastewater,and a strain Y7 was identified through the physiological and biochemical characterization and the 16S rRNA gene sequence analysis. The effects of carbon sources,nitrite concentration,pH,liquid volume,inoculum size,inoculum age and temperature to the removal rate of nitrite-nitrogen by the strain Y7 were further investigated for increasing the efficacy of removing nitrite-nitrogen. As results,strain Y7 was identified as a member of the genus Bacillus and hence designated Bacillus subtilis Y7. Results of single-factor experiment showed that strain Y7 degraded nitrite from 1 100 mg/L to zero after fermentation for 24 hours at temperature 30℃ and 170 r/min,under the conditions of the glycerol as carbon source,the pH value of the medium being 7.0,the liquid volume being 100 mL in 250 mL triangular flask and the inoculum size being 10%(OD600=1.5). In conclusion,strain Y7 tolerates up to 1 100 mg/L nitrite,and the high temperature of 50℃ does not affect its degradation efficiency to the nitrite-nitrogen. Therefore,strain Y7 has great potential in the treatment of high-temperature industrial wastewater containing high concentration of nitrite and summer aquaculture wastewater.
作者
李誉琦
马佩钰
刘涵
王灵芝
高仁玲
李慧娟
LI Yu-qi;MA Pei-yu;LIU Han;WANG Ling-zhi;GAO Ren-ling;LI Hui-juan(College of Chemistry and Environmental Engineering,Shandong University of Science and Technology,Qingdao 266590;School ofLife Science,Beijing University of Chinese Medicine,Beijing 102488)
出处
《生物技术通报》
CAS
CSCD
北大核心
2019年第9期194-201,共8页
Biotechnology Bulletin
基金
国家自然科学基金项目(81872972)
关键词
芽孢杆菌
亚硝酸盐
反硝化细菌
高温
Bacillus
nitrite
denitrifying bacteria
high temperature
