本文研究了注射含微囊藻毒素的微囊藻细胞抽提液对小鼠血液以及免疫系统的亚慢性毒性作用。实验分为3个处理组和1个对照组(每组10只昆明小鼠,雌雄各半),采用腹腔注射的染毒方法对3个处理组进行暴露,剂量分别为2.4、4.8和9.6μg microcys...本文研究了注射含微囊藻毒素的微囊藻细胞抽提液对小鼠血液以及免疫系统的亚慢性毒性作用。实验分为3个处理组和1个对照组(每组10只昆明小鼠,雌雄各半),采用腹腔注射的染毒方法对3个处理组进行暴露,剂量分别为2.4、4.8和9.6μg microcystin-LR/kg body weigh,对照组注射等量的生理盐水,连续注射14d。实验结果表明,14d染毒后,小鼠的肝体比和脾体比都明显增大(p<0.05),同时在9.6μg/kg处理组,血清丙氨酸转移酶、天冬氨酸转移酶、乳酸脱氢酶和碱性磷酸酶活性与对照相比明显升高,但血清总蛋白、白蛋白和白蛋白/球蛋白比率下降。这些指标的变化说明,含微囊藻毒素的微囊藻细胞提取液对处理组小鼠肝脏造成了损伤,肝组织学观察也印证了这个结果,在处理组小鼠肝组织有明显的水样变性。另外,9.6μg/kg处理组小鼠血液白细胞数量比对照组明显减少。组织细胞学观察发现,处理组小鼠脾脏也有明显的损伤。该实验结果说明,含微囊藻毒素的微囊藻细胞抽提液对小鼠的血液和免役系统都产生了一定程度的损伤。展开更多
[Objective]The relationship between signal molecule N-acety-homoserine lactones（AHLs） and Microcystis aeruginosa cell apoptosis was studied.[Method]With M.aeruginosa as the test materials treated by 5 μmol/L N-acet...[Objective]The relationship between signal molecule N-acety-homoserine lactones（AHLs） and Microcystis aeruginosa cell apoptosis was studied.[Method]With M.aeruginosa as the test materials treated by 5 μmol/L N-acety-homoserine lactones（AHLs）,the morphology of cell apoptosis was observed through staining with DAPI.[Result]Microcystis aeruginosa cell apoptosis was induced by signal molecule N-acetyhomoserine lactones（AHLs） with the concentration of 1 μmol/L to inhibit the growth and proliferation of Microcystis aeruginosa.[Conclusion] The results provided the important scientific basis and new management ideas for the treatment of water bloom of Microcystis aeruginosa.展开更多
Rice straw is supposed to be an environment-friendly biomaterial for inhibiting the growth of harmful blooms of the cyanobacterium Microcystis aeruginosa. However, its potential mechanism is not well known. To explore...Rice straw is supposed to be an environment-friendly biomaterial for inhibiting the growth of harmful blooms of the cyanobacterium Microcystis aeruginosa. However, its potential mechanism is not well known. To explore this mechanism, the growth, cell viability(esterase activity, membrane potential, and membrane integrity), photosynthesis, and cell size of M. aeruginosa were determined using fl ow cytometry and Phyto-PAM after exposure to rice straw extracts(RSE). The results show that doses from 2.0 to 10.0 g/L of RSE effi ciently inhibited the alga for 15 days, while the physiologic and morphologic responses of the cyanobacteria were time-dependent. RSE interfered with the cell membrane potential, cell size, and in vivo chlorophyll- a fl uorescence on the fi rst day. After 7 days of exposure, RSE was transported into the cytosol, which disrupted enzyme activity and photosynthesis. The cyanobacteria then started to repair its physiology(enzyme activity, photosynthesis) and remained viable, suggesting that rice straw act as an algistatic agent.展开更多
Microcystis often dominates phytoplankton in eutrophic lakes and must survive a long period of cold or dark conditions. However, the survival strategies of Microcystis to withstand cold or dark stress are less well kn...Microcystis often dominates phytoplankton in eutrophic lakes and must survive a long period of cold or dark conditions. However, the survival strategies of Microcystis to withstand cold or dark stress are less well known. In this study, we conducted experiments on the responses of two toxic Microcystis aeruginosa strains （FACHB-905 and FACHB-915） and their microcystin release in conditions of low temperature （15℃ or 4℃, with illumination） or darkness, and subsequent recovery in standard conditions （25℃ with illumination）. On exposure to 15℃, a small decrease in cell viability was observed, but the cell number increased gradually, suggesting that M. aeruginosa FACHB-905 and FACHB-915 cells seem in general tolerant in 15℃. Interestingly, our results show that a higher carotenoid content and microcystin release potentially enhance the fitness of surviving cells at 15℃. M. aeruginosa cells exposed to lower temperature light stress （4℃） did not completely lose viability and retained the ability to reinitiate growth. In darkness, the maximum quantum yield （Fv/Fm） and the maximum electron transport rate （ETRmax） values and cell viability of M. aeruginosa cells gradually decreased with time. During the recovery period, the photosynthetic efficiency of M. aeruginosa reverted to the normal level. Additionally, M. aeruginosa FACHB-905 and FACHB-915 exposed to low temperature had increased caspase-3-1ike activity and DNA fragmentation, which suggests the occurrence of a type of cell death in M. aeruginosa cells under cold stress similar to programmed cell death. Overall, our findings could confer certain advantages on the Microcystis for surviving cold or dark conditions encountered in the annual cycle, and help explain its repeated occurrence in water blooms in large and shallow lakes.展开更多
基金the Henan Innovation Project for University Prominent Research Talents(HAIPURT,2006KYCX021)the Research Project of Henan Normal University(No.521838)the Research Project of the Ministry of Education of China([2006]331)
文摘本文研究了注射含微囊藻毒素的微囊藻细胞抽提液对小鼠血液以及免疫系统的亚慢性毒性作用。实验分为3个处理组和1个对照组(每组10只昆明小鼠,雌雄各半),采用腹腔注射的染毒方法对3个处理组进行暴露,剂量分别为2.4、4.8和9.6μg microcystin-LR/kg body weigh,对照组注射等量的生理盐水,连续注射14d。实验结果表明,14d染毒后,小鼠的肝体比和脾体比都明显增大(p<0.05),同时在9.6μg/kg处理组,血清丙氨酸转移酶、天冬氨酸转移酶、乳酸脱氢酶和碱性磷酸酶活性与对照相比明显升高,但血清总蛋白、白蛋白和白蛋白/球蛋白比率下降。这些指标的变化说明,含微囊藻毒素的微囊藻细胞提取液对处理组小鼠肝脏造成了损伤,肝组织学观察也印证了这个结果,在处理组小鼠肝组织有明显的水样变性。另外,9.6μg/kg处理组小鼠血液白细胞数量比对照组明显减少。组织细胞学观察发现,处理组小鼠脾脏也有明显的损伤。该实验结果说明,含微囊藻毒素的微囊藻细胞抽提液对小鼠的血液和免役系统都产生了一定程度的损伤。
基金The Henan Scientific and Technological innovation Project for University Prominent Young Research Talents(094100510012)the Research Project of the Ministry of Education of China([2006]331)the Key Subject of Zoology,and Fishery in Henan Province,China
基金Supported by National Natural Science Fund(30960036)Key Schoollevel Project of Kunming University(20091016)~~
文摘[Objective]The relationship between signal molecule N-acety-homoserine lactones（AHLs） and Microcystis aeruginosa cell apoptosis was studied.[Method]With M.aeruginosa as the test materials treated by 5 μmol/L N-acety-homoserine lactones（AHLs）,the morphology of cell apoptosis was observed through staining with DAPI.[Result]Microcystis aeruginosa cell apoptosis was induced by signal molecule N-acetyhomoserine lactones（AHLs） with the concentration of 1 μmol/L to inhibit the growth and proliferation of Microcystis aeruginosa.[Conclusion] The results provided the important scientific basis and new management ideas for the treatment of water bloom of Microcystis aeruginosa.
基金Supported by the National Basic Research Program of China(973 Program)(No.2008CB418002)the National Major Science and Technology Program for Water Pollution Control and Treatment(No.2012ZX07103-002)+1 种基金the CAS/SAFEA International Partnership Program for Creative Research Teams of Chinese Academy of Sciences(No.KZZDEW-TZ-08-01)the National Natural Science Foundation of China(No.20807043)
文摘Rice straw is supposed to be an environment-friendly biomaterial for inhibiting the growth of harmful blooms of the cyanobacterium Microcystis aeruginosa. However, its potential mechanism is not well known. To explore this mechanism, the growth, cell viability(esterase activity, membrane potential, and membrane integrity), photosynthesis, and cell size of M. aeruginosa were determined using fl ow cytometry and Phyto-PAM after exposure to rice straw extracts(RSE). The results show that doses from 2.0 to 10.0 g/L of RSE effi ciently inhibited the alga for 15 days, while the physiologic and morphologic responses of the cyanobacteria were time-dependent. RSE interfered with the cell membrane potential, cell size, and in vivo chlorophyll- a fl uorescence on the fi rst day. After 7 days of exposure, RSE was transported into the cytosol, which disrupted enzyme activity and photosynthesis. The cyanobacteria then started to repair its physiology(enzyme activity, photosynthesis) and remained viable, suggesting that rice straw act as an algistatic agent.
基金Supported by the National Natural Science Foundation of China(Nos.31070355,31370418)
文摘Microcystis often dominates phytoplankton in eutrophic lakes and must survive a long period of cold or dark conditions. However, the survival strategies of Microcystis to withstand cold or dark stress are less well known. In this study, we conducted experiments on the responses of two toxic Microcystis aeruginosa strains （FACHB-905 and FACHB-915） and their microcystin release in conditions of low temperature （15℃ or 4℃, with illumination） or darkness, and subsequent recovery in standard conditions （25℃ with illumination）. On exposure to 15℃, a small decrease in cell viability was observed, but the cell number increased gradually, suggesting that M. aeruginosa FACHB-905 and FACHB-915 cells seem in general tolerant in 15℃. Interestingly, our results show that a higher carotenoid content and microcystin release potentially enhance the fitness of surviving cells at 15℃. M. aeruginosa cells exposed to lower temperature light stress （4℃） did not completely lose viability and retained the ability to reinitiate growth. In darkness, the maximum quantum yield （Fv/Fm） and the maximum electron transport rate （ETRmax） values and cell viability of M. aeruginosa cells gradually decreased with time. During the recovery period, the photosynthetic efficiency of M. aeruginosa reverted to the normal level. Additionally, M. aeruginosa FACHB-905 and FACHB-915 exposed to low temperature had increased caspase-3-1ike activity and DNA fragmentation, which suggests the occurrence of a type of cell death in M. aeruginosa cells under cold stress similar to programmed cell death. Overall, our findings could confer certain advantages on the Microcystis for surviving cold or dark conditions encountered in the annual cycle, and help explain its repeated occurrence in water blooms in large and shallow lakes.
