摘要
采用土壤稀释法和平板纯化法,从受阿特拉津污染土壤中分离出三株高效降解菌,通过形态观察、生理生化分析及16S rDNA鉴定,确定菌株的生物学特征和分类地位。同时选用海藻酸钠、聚乙烯醇、明胶和生物炭为载体包埋菌株,比较固定菌株24 h的物理性能。并采用气相色谱和分光光度法,测定固定化菌株、菌株的降解率及生长情况。经16S rDNA鉴定和构建的发育树结果表明3株降解菌分属Shinella、Herbaspirillum、Pseudomonas。菌株均在14 d D600达到最大且降解效率高于85%。综合比较4种固定材料后,确定海藻酸钠为最佳包埋菌体材料,其包埋菌株的机械强度、传质性能及成形性较好,且对菌株降解阿特拉津效果影响小。利用微生物固定化技术可提高菌株的耐受力,该方法为微生物修复污染土壤提供了理论基础。
In this study,3 strains with high-efficiency degradable bacteria were isolated from atrazine contaminated soil by soil dilution method and plate purification method,which were identified by morphologyical observation,physiological and biochemical analysis and 16S rDNA identification.The 3 strains were embeddedin four materials:sodium alginate,polyvinyl alcohol,gelatin,and biochar,and the physical properties of these fixed strains were compared after 24 hours.Meanwhile,the degradation rate and growth of the strains and immobilized strains were monitored by gas chromatography and spectrophotometry.The taxonomy of three degrading bacterias were found and identified by 16S rDNA sequencing and the phylogenetic tree constructed,respectively Shinella,Herbaspirillum,and Pseudomonas.All the strains reac-hed the maximum D600 at 14 days and the degradation efficiency was higher than 85 percent.After comprehensively comparing the 4 kinds of fixing materials,sodium alginate is the most ideal material for embedding strains with its great formability,mechanical strength,and mass transfer performance.Besides,it has little effect on the degradation of atrazine.The microbial immobilization technology canimprove the toelrance of the strains which provides a theoretical basis for microbial remediation of conta-minated soil.
作者
刘丹丹
孙宛玉
王鹤
LIU Dandan;SUN Wanyu;WANG He(College of Environmental and Safety Engineering, Shenyang University of Chemical Technology, Shenyang 110142, China)
出处
《浙江农业学报》
CSCD
北大核心
2021年第6期1078-1087,共10页
Acta Agriculturae Zhejiangensis
基金
辽宁省自然科学基金(201602599)
辽宁省教育厅项目(LQ2017006)。
关键词
阿特拉津
降解菌株
降解率
微生物固定化
atrazine
atrazine-degrading strains
degradation rate
microbial immobilization
