Microcystin accumulation and biochemical responses in the edible clam Corbicula leana P. exposed to cyanobacterial crude extract  

作　　者：Thanh-Luu Pham Kazuya Shimizu Ayako Kanazawa Yu Gao Thanh-Son Dao Motoo Utsumi 

机构地区：[1]Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan [2]Faculty of Life Sciences, Toyo University, Ora-gun, Gunma 374-0193, Japan [3]College of Chemical and Environmental Engineering, Shandong, University of Science and Technology, qingdao 266590, China [4]Ho Chi Minh City University of Technology, 268 Ly Thuon9 Kiet St., Dist. 10, Ho Chi Mirth City, Viet Nam [5]Vietnam Academy of Science and Technology （VAST), Institute of Tropical Biology, 85 Tran Quoc Toan St., Dist. 3, Ho Chi Minh City, Viet Nam

出　　处：《Journal of Environmental Sciences》2016年第6期120-130,共11页环境科学学报（英文版）

基　　金：supported by the Ministry of Education, Culture, Sports, Science, and Technology of Japan (MEXT) under a Ph.D program;supported by Grants-in-Aid for Scientific Research (B) from the Japan Society for the Promotion of Science (JSPS) and MEXT

摘　　要：We investigated the accumulation and effects of cyanobacterial crude extract（CCE）containing microcystins（MCs） on the edible clam Corbicula leana P. Toxic effects were evaluated through the activity of antioxidant and detoxification enzymes： catalase（CAT）,superoxide dismutase（SOD）, and glutathione-S-transferases（GSTs） from gills, foot, mantle and remaining soft tissues. Clams were exposed to CCE containing 400 μg MC-LReq/L for10 days and were then kept in toxin-free water for 5 days. Clam accumulated MCs（up to 3.41 ± 0.63 μg/g dry weight（DW） of unbound MC and 0.31 ± 0.013 μg/g DW of covalently bound MC）. Detoxification and antioxidant enzymes in different organs responded differently to CCE during the experiment. The activity of SOD, CAT, and GST in the gills and mantle increased in MC-treated clams. In contrast, CAT and GST activity was significantly inhibited in the foot and mostly only slightly changed in the remaining tissues. The responses of biotransformation, antioxidant enzyme activity to CCE and the fast elimination of MCs during depuration help to explain how the clam can survive for long periods（over a week） during the decay of toxic cyanobacterial blooms in nature.We investigated the accumulation and effects of cyanobacterial crude extract（CCE）containing microcystins（MCs） on the edible clam Corbicula leana P. Toxic effects were evaluated through the activity of antioxidant and detoxification enzymes： catalase（CAT）,superoxide dismutase（SOD）, and glutathione-S-transferases（GSTs） from gills, foot, mantle and remaining soft tissues. Clams were exposed to CCE containing 400 μg MC-LReq/L for10 days and were then kept in toxin-free water for 5 days. Clam accumulated MCs（up to 3.41 ± 0.63 μg/g dry weight（DW） of unbound MC and 0.31 ± 0.013 μg/g DW of covalently bound MC）. Detoxification and antioxidant enzymes in different organs responded differently to CCE during the experiment. The activity of SOD, CAT, and GST in the gills and mantle increased in MC-treated clams. In contrast, CAT and GST activity was significantly inhibited in the foot and mostly only slightly changed in the remaining tissues. The responses of biotransformation, antioxidant enzyme activity to CCE and the fast elimination of MCs during depuration help to explain how the clam can survive for long periods（over a week） during the decay of toxic cyanobacterial blooms in nature.

关 键 词：Bioaccumulation Cyanotoxins Covalently bound microcystins Aqueous extracts 

分 类 号：X52[环境科学与工程—环境工程] X171.5