本文關(guān)鍵詞： 鐵錳代謝菌 硒鐵成礦 生物合成材料 光熱治療 環(huán)丙沙星降解 元素循環(huán) 氧化還原驅(qū)動(dòng)力　出處：《中國(guó)科學(xué)技術(shù)大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：鐵錳代謝菌所具有的氧化還原驅(qū)動(dòng)力是其被應(yīng)用于環(huán)境領(lǐng)域的基礎(chǔ),雖然已有一些關(guān)于鐵錳代謝菌在環(huán)境領(lǐng)域應(yīng)用的報(bào)道,但是對(duì)其在有微量元素成礦機(jī)制、元素循環(huán)與污染物降解中作用的認(rèn)識(shí)尚不夠清晰。本論文主要探索幾種模式鐵錳代謝菌在微量元素成礦、材料生物合成以及污染物降解中的作用。論文的主要內(nèi)容和結(jié)果如下:1.以環(huán)境中含量較高且廣受關(guān)注的Se作為微量元素代表、水合氧化鐵作為自然界中廣泛存在的鐵礦物代表,以鐵錳還原菌Geobacter sulfurreducens為對(duì)象,開展了鐵錳還原菌介導(dǎo)的微量元素成礦試驗(yàn)。通過一系列固相表面的表征,證明了 Geobacter可以實(shí)現(xiàn)水合鐵與Se032-的共還原,且在較長(zhǎng)的時(shí)間尺度下(120天)能夠在HFO表面形成FeSe復(fù)合物。此外,還證明了Geobactr的鐵還原過程受電子供體種類和電子穿梭體存在與否的影響,發(fā)現(xiàn)以氫氣作為電子供體能夠加快鐵還原速率但是降低細(xì)菌活性,電子穿梭體的加入則能夠顯著加快鐵的還原速率,彌補(bǔ)了乙酸鈉作為電子供體相對(duì)于氫氣的不足。2.以鐵錳還原菌ShewanellaoneidensisMR-1的胞外還原能力為基礎(chǔ),充分發(fā)揮其能夠利用多種電子供體的優(yōu)勢(shì),胞外合成納米材料。將S2O32-作為S源還原生成S2-,后與Cu2+結(jié)合合成了 CuS納米顆粒;通過投加原料比的調(diào)控,顯著簡(jiǎn)化了納米材料的分離純化步驟,得到了尺寸均一、小粒徑、高分散的CuS納米顆粒;通過對(duì)CuS納米顆粒光熱性能的檢測(cè)表明,該生物合成顆粒具有優(yōu)于貴金屬的光熱轉(zhuǎn)化效率,且擁有優(yōu)異的循環(huán)穩(wěn)定性;利用人肺癌細(xì)胞A594R的體外實(shí)驗(yàn)則顯示出S.oneidensis MR-1生物合成的CuS納米顆粒能夠在不損傷正常組織細(xì)胞的情況下高效殺死癌細(xì)胞。3.以錳氧化物氧化分解環(huán)丙沙星(CIP)為切入點(diǎn),構(gòu)建了生物強(qiáng)化的污染物化學(xué)降解系統(tǒng)。利用PseudomonasputidaMnB-1氧化Mn~(2+)形成MnO_2的能力,通過投加Mn~(2+)獲得高反應(yīng)活性的MnO_2顆粒,從而完成環(huán)丙沙星的高效降解;觀察到MnO_2的存在使細(xì)菌保持活性,實(shí)現(xiàn)將環(huán)丙沙星還原的MnO_2的再次氧化,從而構(gòu)成了錳元素的微生物循環(huán),進(jìn)而實(shí)現(xiàn)了環(huán)丙沙星的非生物降解;Mn(Ⅲ)絡(luò)合劑的加入導(dǎo)致環(huán)丙沙星降解速率的降低,從而證明Mn(Ⅲ)在這該循環(huán)反應(yīng)中所起的促進(jìn)作用。
[Abstract]:The redox driving force of ferromanganese metabolites is the basis of their application in the field of environment. Although there have been some reports on the application of ferromanganese metabolites in the field of environment, there are metallogenic mechanisms of trace elements in them. The role of element cycling and pollutant degradation is not clear. In this paper, several models of iron and manganese metabolism bacteria in trace element mineralization. The main contents and results of this paper are as follows: 1. The high content of se in the environment and its widespread concern are taken as the representative of trace elements. As the representative of iron minerals widely existed in nature, hydrated iron oxide takes ferromanganese reducing bacteria Geobacter sulfurreducens as the object. Through a series of solid surface characterization, it is proved that Geobacter can realize the co-reduction of iron hydrate and Se032-. In addition, FeSe complex can be formed on the surface of HFO at a longer time scale (120 days). It is also proved that the process of iron reduction of Geobactr is affected by the type of electron donor and the existence of electron shuttle. It is found that hydrogen can accelerate the rate of iron reduction but reduce the activity of bacteria. The addition of electron shuttle can significantly accelerate the reduction rate of iron. It makes up the deficiency of sodium acetate as electron donor relative to hydrogen. It is based on the extracellular reduction ability of ferromanganese reducing bacteria ShewanellaoneidensisMR-1. S2O32- was used as the source of S to form S2-and then combined with Cu2 to synthesize CuS nanoparticles. By adjusting the ratio of raw materials, the separation and purification of nanomaterials were greatly simplified, and CuS nanoparticles with uniform size, small particle size and high dispersion were obtained. The photothermal properties of CuS nanoparticles showed that the biosynthetic particles were superior to precious metals in photothermal conversion efficiency and had excellent cycling stability. In vitro experiments using human lung cancer cell line A594R showed that S. oneidensis. The CuS nanoparticles synthesized by MR-1 can efficiently kill cancer cells without damaging normal tissue cells. The oxidative decomposition of ciprofloxacin (ciprofloxacin) with manganese oxide (MNO). CIP) as the entry point. A bioenhanced chemical degradation system for pollutants was constructed. The ability of PseudomonasputidaMnB-1 to oxidize Mn~(2 to form MnO_2 was established. The highly reactive MnO_2 particles were obtained by adding Mn~(2) to achieve the efficient degradation of ciprofloxacin. It was observed that the presence of MnO_2 kept the bacteria active and reoxidized the MnO_2 that reduced ciprofloxacin, thus forming the microbial cycle of manganese. The non-biodegradation of ciprofloxacin was realized. The addition of mn (鈪，

本文編號(hào)：1471123