IHB OpenIR  > 学位论文
两株溶藻细菌的分离及其溶藻特性
Alternative TitleIsolation of Two Algae-Lysing Bacteria and Their Algae-Lytic Characters
卢兰兰
Subtype硕士
Thesis Advisor刘永定
2008-06-14
Degree Grantor中国科学院水生生物研究所
Place of Conferral水生生物研究所
Keyword溶藻细菌 蓝藻 分离 芽孢杆菌 培养条件
Abstract有害藻类水华的频繁暴发己成为世界性的环境灾害,严重影响人类生活、生产和身体健康,危害生态系统的可持续发展。探索控制藻类水华的有效途径是非常迫切的。微生物特别是溶藻细菌在控制水华暴发方面有巨大的潜力和应用前景。本研究从滇池水体分离到两株高效的溶藻细菌,初步研究其溶藻效果、溶藻范围、生物安全性、作用机理、培养条件和实际应用效果,结果如下: 1)从滇池水华集聚区分离到两株溶解铜绿微囊藻的细菌,编号为DC-L5和DC-L14。经中国典型培养物武汉保藏中心鉴定为Bacillus pumilus和Lysinibacillus fusiformis。用小白鼠进行生物安全实验,小白鼠无中毒症状。两株细菌能使滇池水华藻类——惠氏微囊藻、绿色微囊藻、水华束丝藻和水华鱼腥藻的Chl.a浓度4 d平均下降62.25%和67.20%。 2)DC-L5和DC-L14分别在对数生长期和稳定生长期的溶藻效果最强,5 d能使铜绿微囊藻的Chl.a浓度下降83.33%和82.10%。DC-L5可能是通过直接接触使铜绿微囊藻细胞凝聚下沉及进一步的生物降解,同时,存在抑制藻细胞生长的胞外分泌物,此物质不耐高温;DC-L5溶解自然藻华微囊藻时先破坏其群体性和漂浮性,再降解单细胞藻的色素和释放其他内含物。DC-L14可能是通过分泌溶藻物质溶藻,该物质应为非蛋白质类,高温可能有利于溶藻物质的释放。 3)DC-L14生长的最适温度为35 ℃,最适pH为7.5。在肉汤培养基中分别添加1%葡萄糖、0.1% MgSO4和0.1% KH2PO4,使DC-L14浓度分别提高24.53%、14.94% 和12.46%,溶藻效果分别提高11.10%、2.75%、3.80%。按照正交实验设计添加1 %葡萄糖、0.1% MgSO4和0.2% KH2PO4,细菌浓度提高20.36%,溶藻效果提高8.86%。 4)室内溶藻试验结果显示,DC-L5对单藻培养物和自然藻华都有较强的溶藻能力。DC-L5种群的增长和溶藻效果在单藻培养物中比在自然藻华中更明显;添加DC-L5到室内培养的单藻培养物和自然藻华中,TP、TN和CODMn都升高,pH保持稳定。随着作用时间的延长,TP保持较高浓度,TN和CODMn显著下降;滇池围隔内溶藻应用试验结果显示,DC-L5能使试验水体叶绿素下降,透明度提高,第4 d溶藻效果最明显,持续时间13 d左右。
Other AbstractThe occurence of harmful algal blooms (HAB) widely in the world has recently increased as a global environment problem, which affects people's life, health, productive activities and the sustainable development of ecosystems severely. It is necessary to look for some effective methods to control HAB. Algae-lysing bacteria have been regarded as a candidative measure of microbiological control on water bloom with more and more concern. In this study, two high-effect algae-lysing bacteria were isolated and purified from Lake Dianchi. The effect, host range, biosafety, lysing mechanism, culture condtion and application test of these two algae-lysing bacteria were analyzed. Results are as the followings. 1) Two algae-lysing bacteria were isolated from the heavy cyanobacterial blooming area of Lake Dianchi, which were labeled as DC-L5 and DC-L14. They were identified as Bacillus pumilus and Lysinibacillus fusiformiseir respectively by means of morphological observation and 16S rDNA sequence analysis in the CCTCC. Toxicity test with mouse primarily showed that the two bacterial strains were non-toxic. For the lysing effect, average reduction rates of Chlorophyll a of 62.25% and 67.20% in cultures of Microcystis viridis, Microcystis wesenbergii, Aphanizomenon flos-aquae and Anabaena flos-aquae with the two bacteria in 4 days were observed. 2) The strongest algae-lytic abilities were found in the log and stationary phases of DC-L5 and DC-L14 cultures, Chlorophyll a contents in cultures of Microcystis aeruginosa reduced by 83.33% and 82.10% respectively in 5 days . Strain DC-L5 could directly cause the cyanobacterial cells agglomerated, sinked down and further lysed; while this strain could excrete extra-cellular substances able to lysing cyanobacterial cells. With wild Microcystis aeruginosa bloom, Strain DC-L5 firstly disaggregated the cyanobacterial colony, reduced the floatability, degraded the pigments and then released inclusions of algal cells. Extracellular substance produced by strain DC-L14 was thermostable, and high temperature possibly reinforced the release of this kind of substance. 3) For the cultivation of DC-L4 in broth medium, the optimal pH was 7.5 and cultural temperature was 35 ℃. Test of adding carbon source, and inorganic salt into the culture, showed that, additional glucose (1%, w/w), MgSO4 (0.1%) and KH2PO4 (0.1%) could enhance the cell number of DC-L14 by 24.53%, 14.94% and 12.46% respectively, and reduced the Chl.a content of bloom by 11.10%, 2.75% and 3.80% in correspondance. Thus, it can be taken in account that, the recipe of fermentation medium would be optimized through the uniform-design. A suitable fermentation condition for culture of DC-L14 could be optimalized as adding 1%glucose, 0.1 %MgSO4 and 0.2% KH2PO4 into broth medium, by which, the culture of DC-L14 could increase by 20.36% and the Chl.a content of bloom could reduced by 8.86%. 4) The algae-lysing results showed that, DC-L5 was a well algae-lytic strain against Microcystis aeruginosa both in uni-algal culture and with wild bloom from lake, but more obvious Chl.a decrese was observed in the former case than in the latter one. On the other hand, results showed that, algae-lysing caused changes in water chemistry as, adding strain DC-L5 into uni-algal culture of and the wild bloom dominant with Microcystis aeruginosa, the content of TN, TP and CODMn increased soon, then the content of TP remained at a high level, meanwhile the content of TN and CODMn reduced obviousely. Algae-lysing results in an experimental enclosure in Lake Dianchi showed that DC-L5 could reduce the content of Chl.a and improve the SD in the water body, the best algae-lytic effect displayed on the 4th day, and the effect could last for 13 days.
Pages77
Language中文
Document Type学位论文
Identifierhttp://ir.ihb.ac.cn/handle/342005/12342
Collection学位论文
Recommended Citation
GB/T 7714
卢兰兰. 两株溶藻细菌的分离及其溶藻特性[D]. 水生生物研究所. 中国科学院水生生物研究所,2008.
Files in This Item:
File Name/Size DocType Version Access License
10001_20052801191505(1337KB) 限制开放--View Application Full Text
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[卢兰兰]'s Articles
Baidu academic
Similar articles in Baidu academic
[卢兰兰]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[卢兰兰]'s Articles
Terms of Use
No data!
Social Bookmark/Share
File name: 10001_200528011915052卢兰兰_paper.pdf
Format: Adobe PDF
This file does not support browsing at this time
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.