土壤微生物对铜、镍和矿物浮选捕收剂的单一和交互作用的响应—细胞和群落层面的分析

发布时间：2020-09-28 20:21

　　来自采矿和矿石加工排放的金属及其相关的矿物浮选试剂产生的污染具有很大的生态和健康影响,需要加以充分理解和解决。本研究旨在分析镍,铜和最有效和常用的硫化物矿物浮选捕收剂,如黄原酸盐,异戊基黄原酸钠(SIAX),异丁基黄原酸钠(SIBX),异丙基黄原酸钠(SIPX),乙基黄原酸钠(SEX),戊基黄原酸钾(PAX)和乙基黄原酸钾(PEX)对土壤微生物群落单独和联合的效应。通过不同的补充方法进行分析,主要是微生物生长(细胞密度和活细胞计数)和酶活性(过氧化氢酶和FDA水解)的测量,土壤微生物活动的微量量热测定,以及基于分子生物学的不同剂量化学剂下的微生物群落结构和多样性分析。所有黄原酸盐剂量均对土壤微生物生长、过氧化氢酶和FDA水解活性产生不利影响,呈现剂量-效应正相关,且随着培养时间的延长抑制率呈下降趋势。在所有分析参数中,SIPX 比SIBX更不利。Cu、Ni和黄原酸盐均表现出剂量-效应正相关关系,Cu、Ni、SIPX、PAX、SIAX、SEX、PEX的抑制浓度(IC50)分别为447.5、438.69、225.76、158.3、83.95、74.08和39.63。与其相应的金属混合物相比,黄原酸盐对微生物活性的抑制作用更强。在大多数情况下,化学品混合物的抑制率低于相应的混合物组分抑制率的总和,这种情况对应于拮抗型反应。单一最不利的黄原酸盐与较低的混合逆境相关(即,PEX在有镍的混合的情况下,SIAX在有铜的混合的情况下)。与对照样品相比,所有处理的样品表现出较低的微生物丰富度和多样性,最低值与含有铜的化学混合物有关。六种最丰富的门是Proteobacteria(56.7%),Firmicutes(22%),Actinobacteria(10.53%),Bacteroidetes(3.26%),Acidobacteria(2.80%)和Chloroflexi(2.242%)。每个样品或样品组中最优势的物种是对照样品中的Bacillus selenatarsenatis(17%),铜处理样品中的unclassified_f_Micrococcaceae(40.31%),镍处理样品中unclassified_f_/Micrococcaceae(19.97%),较低浓度黄原酸盐处理样品(50μg.g-l 土壤)中的 Cupriavidus taiwanensis(19%),较高浓度黄原酸盐处理样品(100μHg.g-l 土)中的unclassified_f_Enterobacteriaceae(31%),Cupriavidus taiwanensis(45.32%)存在于较低黄原酸盐,unclassified_g_seudomo as(51.06)存在较高黄原酸盐剂量和铜混合物中,Bacillus korlensis(25.04 9,%)存在于较低黄原酸盐剂量混合物中,以及镍于较高黄原酸盐剂量混合物中(35.14%)。分别在铜、镍和黄原酸盐单一和混合处理中,发现了具有潜在适应能力或受影响较小的细菌种类,并应进行进一步分析,以确定它们的耐药能力和潜在的生物技术应用。
【学位单位】：北京科技大学
【学位级别】：博士
【学位年份】：2019
【中图分类】：X172;X75
【文章目录】：
Acknowledgement
摘要
Abstract
List of abbreviations and symbols
1 Introduction
    1.1 Research background
    1.2 Study interest and motivation
    1.3 Research hypotheses and objectives
    1.4 Dissertation structure
2 Literature review
    2.1 Metals occurrence, distribution and fate in the environment
        2.1.1 Occurrence and distribution in the environment
        2.1.2 Fate in the soil end environment
        2.1.3 Effect of metals on the living system
        2.1.4 Microbial adaptation to metal toxicity
    2.2 Xanthates use and interaction with the living organisms
        2.2.1 Xanthates use in flotation and its environmental implication
        2.2.2 Interactions between xanthates and the living organisms
3 Research content and methodology
    3.1 Introduction to methods in soil microbial ecology
    3.2 Material
        3.2.1 Samples collection and analysis
        3.2.2 Reagents
    3.3 Experimentation
        3.3.1 Turbidimetric measurement
        3.3.2 Spread plating and viable cell count
        3.3.3 Microcalorimetric measurement
        3.3.4 Enzymes activities measurement
            3.3.4.1 Catalase activity
            3.3.4.2 Fluorescein diacetate (FDA) hydrolyases activity
        3.3.5 Molecular biology-based analysis
    3.4 Data analysis
4 Toxic effects of xanthates on soil microbial community and enzymes activities
    4.1 Turbidity measurement
    4.2 Microbial viable cell count
    4.3 Enzymes activity analysis
        4.3.1 FDA hydrolyases activity
        4.3.2 Catalase activity
        4.3.3 Comparison between FDA hydrolyases and catalase activities
    4.4 Discussion
    4.5 Summary
5 Interactive effects of nickel,copper, and minerals collectors on soil microbialactivity
    5.1 Single toxicity of Ni, Cu and minerals collectors
    5.2 Interactive effects of Ni and its flotation collectors
    5.3 Interactive effects of Cu and xanthates (SIAX and PAX)
    5.4 Discussion
    5.5 Summary
6 Single and interactive effect of nickel,copper and xanthates on the soilmicrobial diversity and structure-Molecular approach
    6.1 Bacterial community diversity
    6.2 Venn diagram analysis
    6.3 Simples distance matrix
    6.4 Bacterial community composition
    6.5 Discussion
    6.6 Traits of potentially nickel and xanthates tolerant bacteria
    6.7 Summary
7 Conclusions and recommendations
    7.1 General conclusions
    7.2 Research contribution
    7.3 Recommendation
References
作者简历及在学研究成果
学位论文数据集

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