유해 녹조 제어를 위한 2,4-thiazolidinedione 유도체 합성 및 활성평가

Abstract

The harmful algae species have often caused algae bloom in the Nakdong River and other parts of Korea recently, and it leads to great economic loss due to declining value of water resources and increasing cost of water treatment. Therefore, this study intended to synthesize the environment-friendly algicide that is highly effective in eliminating algae and yet not toxic to other species. 64 new derivatives of 2,4-thiazolidinedione, which was used as the derivatives of many compounds and proven to be safe, were synthesized, and the change of activity according to the structure was measured using the SAR (structure activity relationship). To select the most active compound among the synthesized derivatives, the algicidal effects against the microcystis aeruginosa, anabaena flos-aquae and aphnizomenon flos-aquae were evaluated and an ecotoxicology test using the zebra fish (daphnia magna) and an acute ecotoxicology test using the water flea (danio rerio) were conducted to assess the biological stability. Although the most new derivatives were highly active against the microcystis aeruginosa, they were not active against the anabaena flos-aquae or aphnizomenon flos-aquae. The compound that showed the most algicidal efficient against microcystis aeruginosa was the compound 52 which had the LC50 value of 0.318 μM. The compounds generally showed higher algicidal efficiency when the exchange reagents were applied. However, the compounds with the halogen substituents showed high toxicity to zebra fish and water flea while the compounds with the hydroxyl and alkoxy substituents showed lower toxicity. Therefore, the compound 2, 5-(2-hydroxy-3-methoxybenzylidene)thiazolidine-2,4-dio ne, which showed outstanding algicidal capability and yet much lower toxicity than the compound 52, was finally selected. The compound 2 developed in this study is judged to be the environment-friendly algicide that is less toxic to ecosystem and can effectively and selectively control microcystis aeruginosa.