【作者】 陈晓雯；

【导师】 杨劭；

【作者基本信息】 华中师范大学 ， 微生物学， 2008， 硕士

【摘要】 从大量合成化合物中筛选出一种微囊藻杀藻剂的先导化合物MS1,当MS1的浓度大于等于1 mg·L^-1时,3d内使铜绿微囊藻DS（Microcystis aeruginosa）的细胞密度降低90%。MS1对铜绿微囊藻DS、7806、7820生长抑制率的72h-EC50均小于0.25 mg·L^-1。而MS1对水华鱼腥藻（Anabaena flosaquae 7120）、纤细裸藻（Euglenagracilis）、莱因衣藻（Chlamydomonas reinhardtii）、舟型藻（Navicula pelliculosa）、斜生栅藻（Scenedesmus obliquu）生长抑制率的72h-EC₅₀分别为12.76、32.3、3.13、10.17和22.4 mg·L^-1,证明这几种藻对MS1的敏感程度相对较低。MS1对浮游动物大型溞（Daphnia Magna）和淡水鱼青鳉（Oryzias latipes）的死亡率72h-LC₅₀分别为1.33 mg·L^-1和1.04mg·L^-1。可见此杀藻剂先导化合物对微囊藻杀灭活性高,专一性较强,但对浮游动物和鱼类的毒性偏大。通过对MS1的基团修饰可降低其环境残留期及对非靶标的毒性,通过此先导化合物合成的杀藻剂,适用于景观水体和工业水处理的杀藻。为了解MS1对微囊藻的杀藻机制,以铜绿微囊藻DS为实验材料,采用室内培养的方法,在各杀藻剂浓度下暴露后分别测定铜绿微囊藻DS的生长量、叶绿素、总蛋白含量等生理生化指标。结果表明,随着MS1的浓度增大,铜绿微囊藻的细胞密度降低,光合色素量减少,总蛋白的含量降低,细胞内MDA的含量仅在低浓度时增加。当MS1浓度大于等于1mg·L^-1时,24h内藻细胞内的总蛋白含量比对照出现显著差异,预计暴露时间延长,其蛋白合成的抑制可能更为显著,因此推测MS1主要的杀藻机理是抑制蛋白质的合成,同时也抑制了叶绿素的合成。更多还原

【Abstract】 Alead compound of algaecide,named MS1,was obtained by screening a number of synthesized chemicals.MS1(≥1 mg·L^-1)decreased the cell density of Microcystis aeruginosa DS by 90%in 3d treatment.72h-EC₅₀of MS1 on Microcystis aeruginosa DS, 7806,and 7820 were all less than 0.25 mg·L^-1,while 72h-EC₅₀of MS1 on Anabaena flosaquae 7120,Euglena gracilis,Chlamydomonas reinhardtii,Navicula pelliculosa,and Scenedesmus obliquu were 12.76,32.3,3.13,10.17 and 22.4 mg·L^-1respectively.The results showed those algal species were less sensitive than Microcystis aeruginosa to MS1.The acute toxicity test of Oryzias latipes and Daphnia Magna to MS1 showed that the 72h-LC₅₀were 1.04 mg·L^-1and 1.33mg·L^-1respectively.The data above indicates MS1 high and specific algaecidal effect on Microcystis but also toxic to fish and zooplankton.As a lead compound of algaecide,it can be modified by changing side groups of the chemical structure to reduce its toxicity to non-target organisms and increase its degradability in the environment.MS1 derivative algaecides can be applied to urban water bodies and industrial water treatment.In order to study the toxic effects of MSl on the M.aeruginosa DS,the algae was exposed to MS1 to measure the content of photosynthetic pigment,MDA,and protein. Results showed that,MSl had inhibition effect on growth of M.aeruginosa DS compared with the control.With the increase of concentrations,the inhibition increased correspondingly.MDA contents increased significantly（compared with the control, p＜0.01）,only when concentration of MS1 was in a low level.Protein contents decreased significantly（p＜0.05）,when concentration of MS1 was higher than 1 mg’L^-1.It indicated the main mechanism of MS1 inhibition in M.aeruginosa was inhibition the synthesis of protein and chlorophyll.更多还原