【摘要】：生物修復(fù)方法由于其具有經(jīng)濟(jì)、生態(tài)效益等優(yōu)點(diǎn)而在重金屬污染治理中占據(jù)優(yōu)勢(shì)地位,而微生物作為生態(tài)修復(fù)的一個(gè)主體,在治理重金屬污染中起著重要作用。本研究取樣于湖南資興鉛鋅礦耐鉛鋅植物盆栽試驗(yàn)中長勢(shì)較好的植株夾竹桃的根系,對(duì)篩選、馴化所得菌株進(jìn)行了耐受性、生理生化等特性的研究,并進(jìn)行了分類學(xué)鑒定與電鏡掃描、傅里葉變換紅外光譜分析。具體實(shí)驗(yàn)結(jié)論如下：(1)經(jīng)過一系列分離、篩選及馴化實(shí)驗(yàn)得到了26株鉛鋅抗性菌,編號(hào)B1-B26。通過比較26株細(xì)菌在所設(shè)計(jì)的Pb (Ⅱ)、Zn (Ⅱ)不同濃度梯度培養(yǎng)基中的OD600,將生長量較高的B1、B4、B14確定為優(yōu)勢(shì)菌株。B1、B4、B14對(duì)Pb(Ⅱ)、Zn (Ⅱ)的最高耐受濃度分別可達(dá)800mg/L、800mg/L、600mg/L。(2)通過三株優(yōu)勢(shì)菌的富集特性研究,發(fā)現(xiàn)菌株B1在溫度為30℃、Pb (Ⅱ)和Zn (Ⅱ)初始濃度為50 mg/L、轉(zhuǎn)速為180r·min-1、pH5.0、吸附時(shí)間為50mmin、初始菌量為0.06g時(shí),對(duì)Pb (Ⅱ)、Zn (Ⅱ)的吸附率分別為84.22%、70.66%；菌株B4在溫度為30℃、Pb (Ⅱ)和Zn (Ⅱ)初始濃度為50 mg/L、轉(zhuǎn)速為180r·min-1,pH為6.0、吸附時(shí)間為50min、初始菌量為0.18g時(shí),對(duì)Pb (Ⅱ)、Zn (Ⅱ)的吸附率分別為72.63%、54.17%；菌株B14在溫度為30℃、Pb (Ⅱ)和Zn (Ⅱ)初始濃度為50mg/L、轉(zhuǎn)速為180r·min-1,pH為4.0、吸附時(shí)間為60min、初始菌量為0.10g時(shí),對(duì)Pb (Ⅱ)、Zn (Ⅱ)的吸附率分別為77.56%、50.63%。以上試驗(yàn)結(jié)果表明,篩選的三株優(yōu)勢(shì)菌在鉛、鋅污染土壤的修復(fù)和含Pb (Ⅱ)、Zn (Ⅱ)廢水的處理中將具有良好的應(yīng)用前景。(3)對(duì)三株優(yōu)勢(shì)菌株進(jìn)行了菌落形態(tài)觀察、革蘭氏染色、16S rDNA分子鑒定,然后把所得的三株菌的16S rDNA序列輸入NCBI進(jìn)行Blast比對(duì),得到與該細(xì)菌16S rDNA序列的同源性最高的已知序列。經(jīng)比對(duì)確定B1為蠟樣芽孢桿菌(Bacillus cereus)或炭疽桿菌(Bacillus anthracis);B4為解硫胺素硫胺素芽孢桿菌(Aneurinibacillus aneurinilyticus);B14為藤黃微球菌(Micrococcus luteus)。(4)電鏡掃描顯示在含Pb (Ⅱ)、Zn (Ⅱ)培養(yǎng)基中培養(yǎng)過的菌體細(xì)胞發(fā)生了畸變,部分菌體細(xì)胞發(fā)生破裂或聚集,菌體表面產(chǎn)生大量晶體以及絮狀或球形沉淀。傅里葉變換紅外光譜分析(FTIR)說明B1、B4、B14菌體細(xì)胞富含羥基(-O-H)、胺基(-N-H)、烷基、酰胺基(CONH-)、羧基(O=C-O-)、磷酸基(-PO43-)等多種活性基團(tuán)。對(duì)吸附前、后菌體的傅里葉變換紅外光譜圖進(jìn)行對(duì)比分析,發(fā)現(xiàn)羥基(O-H)、胺基(N-H)、烷基、酰胺基(CONH-)是吸附、絡(luò)合或螯合重金屬離子或原子的主要活性基團(tuán),重金屬與菌株表面的活性基團(tuán)結(jié)合反應(yīng)是其吸附Pb (Ⅱ)、Zn (Ⅱ)的主要作用機(jī)制。
[Abstract]:Bioremediation plays an important role in the treatment of heavy metal pollution because of its economic and ecological benefits. As a main body of ecological remediation, microorganisms play an important role in the treatment of heavy metal pollution. In this study, we sampled the roots of nectarine, which grew well in the pot experiment of lead-zinc tolerant plants in Zixing lead-zinc mine, Hunan Province, and studied the tolerance, physiological and biochemical characteristics of the selected and domesticated strains. The taxonomic identification, scanning electron microscope and Fourier transform infrared spectroscopy (FTIR) were carried out. The results are as follows: (1) after a series of isolation, screening and acclimation experiments, 26 strains of lead and zinc resistant bacteria were obtained, numbered B1-B26. By comparing the OD600, of 26 strains of bacteria in the Pb (鈪，

本文編號(hào)：2314873