本文選題：氣單胞菌 + 胞外物質(zhì)�。� 參考：《山東大學(xué)》2015年碩士論文

【摘要】：水體富營(yíng)養(yǎng)化程度日益加劇,藻類(lèi)水華頻發(fā),已經(jīng)成為困擾我國(guó)乃至世界的較為嚴(yán)重的環(huán)境污染問(wèn)題之一。目前對(duì)于藻類(lèi)水華的治理方法包括物理措施、化學(xué)措施和生物措施等,其中以溶藻細(xì)菌為代表的微生物抑藻技術(shù)嶄露頭角,成為人們?nèi)找骊P(guān)注和研究的焦點(diǎn)。課題組前期從水庫(kù)中分離獲得一株溶藻細(xì)菌FM,經(jīng)鑒定為氣單胞菌(Aeromonas sp. strain FM)。本文在此基礎(chǔ)上以水華暴發(fā)常見(jiàn)藻類(lèi)銅綠微囊藻(Microcystis aeruginosa)為研究對(duì)象,初步探討了氣單胞菌菌株FM的胞外物質(zhì)對(duì)銅綠微囊藻生理生化特性的影響,主要研究結(jié)果如下：1)菌藻密度和環(huán)境因素對(duì)氣單胞菌菌株FM的溶藻效應(yīng)的影響。當(dāng)氣單胞菌初始菌濃度達(dá)到3.4×108cfu·mL-1及以上時(shí),具有明顯的溶藻效果,可有效作用于藻密度達(dá)到2.45×107cells · mL-1的銅綠微囊藻；溶藻效應(yīng)發(fā)生的最佳溫度為25℃,菌藻共培養(yǎng)體系處于偏堿性環(huán)境,且在光照充分條件下溶藻效果更好。2)以LB液體培養(yǎng)基培養(yǎng)氣單胞菌菌株FM、制備具有溶藻活性的胞外物質(zhì),優(yōu)化培養(yǎng)方法與培養(yǎng)條件。經(jīng)優(yōu)化獲得的最佳培養(yǎng)時(shí)間為24h,溫度為30。C,pH為8。經(jīng)液體培養(yǎng)和固體平板培養(yǎng)菌株FM制備得到的細(xì)菌胞外物質(zhì)對(duì)銅綠微囊藻均具有良好的溶藻效果,8天的溶藻效率分別為86.0%和84.7%。3)氣單胞菌FM對(duì)銅綠微囊藻的生理生化指標(biāo)的影響。檢測(cè)分析表明,氣單胞菌FM通過(guò)分泌胞外物質(zhì)作用于銅綠微囊藻細(xì)胞,藻細(xì)胞胞內(nèi)總蛋白和部分酶的含量降低,藻細(xì)胞的生理代謝活性發(fā)生改變；同時(shí)藻細(xì)胞的抗氧化能力被激發(fā),膜脂過(guò)氧化水平提高；另外,藻細(xì)胞通過(guò)分泌胞外多糖保護(hù)自身免受傷害,藻細(xì)胞生長(zhǎng)受到抑制,最終導(dǎo)致藻細(xì)胞的裂解和死亡。4)對(duì)處理第7天的銅綠微囊藻多糖進(jìn)行提純和制備,并初步研究其化學(xué)性質(zhì),結(jié)果表明：實(shí)驗(yàn)組的藻多糖干重明顯高于空白組；在菌株FM胞外物質(zhì)的作用下,藻細(xì)胞多糖的分子量比對(duì)照組有升高的趨勢(shì)；經(jīng)檢測(cè)藻細(xì)胞多糖中含總糖、糖醛酸和硫酸根等組分。5)氣單胞菌胞外物質(zhì)對(duì)銅綠微囊藻藻毒素的釋放有一定的抑制作用。但投加的氣單胞菌胞外物質(zhì)濃度較高時(shí),會(huì)導(dǎo)致藻細(xì)胞破裂,使得胞外藻毒素含量明顯升高。隨著氣單胞菌胞外物質(zhì)濃度的增加,銅綠微囊藻胞內(nèi)藻毒素的含量降低,同樣表明氣單胞菌胞外物質(zhì)對(duì)銅綠微囊藻的生理代謝過(guò)程具有顯著影響。
[Abstract]:The degree of eutrophication in water is becoming more and more serious, and the frequent occurrence of algae Shui Hua has become one of the more serious environmental pollution problems in our country and even in the world. At present, the control methods of algae Shui Hua include physical, chemical and biological measures, among which the microorganism inhibition technology, represented by algae-lysing bacteria, has become the focus of more and more attention and research. A algae-lysing bacterium, FM, was isolated from the reservoir and identified as Aeromonas sp. strain FM. On this basis, the effects of extracellular substances of Aeromonas aeruginosa strain FM on the physiological and biochemical characteristics of microcystis aeruginosa were studied. The main results were as follows: (1) the effect of algal density and environmental factors on the algae-lysing effect of Aeromonas aeruginosa strain FM. When the initial concentration of Aeromonas aeruginosa reached 3.4 脳 108cfu mL-1 and above, it had obvious algolytic effect, and could effectively act on microcystis aeruginosa with algae density up to 2.45 脳 107cells mL-1, and the optimum temperature for algolytic effect was 25 鈩，

本文編號(hào)：1922588