Development of Loreclezole Derivatives K31565 and K31567 Having Highly Selective Algicidal Effects

Jin-Seog Kim*   Bo Gwan Kim   Yun Gyeong Hwang   Hee Seung Lim   Heejin Park   Byoung-Seok Lee2   Ill Young Lee1   

1Research Center for Eco-Friendly New Materials, Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
2Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon 34114, Korea


This study was conducted to investigate the biological activities of K31565 and K31567 which were screened from loreclezole (Lore) derivatives, on the various microalgae and plant species. Among the tested microalgae, they had a sensitive response in the order of Microcystis aeruginosa (Ma) and Scenedesmus spp. (Sce)>Raphidocelis subcapitata>Chlorella sorokiniana (Cs)>C. vulgaris (KCTC)>C. vulgaris (FBCC), showing the broaded differences in the acitvity among species of microalgae. That is, compared to those of Lore, K31565 and K31567 exhibited slightly higher algicidal activity against Sce (IC90 was 0.11 and 2.25 µM, respectively), significantly higher algicidal activity against Ma (IC90 was 0.14 and 0.28 µM, respectively) and moderately lower against Cs, Cv (KCTC), and Cv (FBCC). On the other hand, their phytotoxicity to various weeds containing Lemna paucicostata were dramatically alleviated and changed into a highly selective compounds compared to Lore. In addition, K31565 and K31567 did not induced any injury and herbicidal symptoms against pepper, rice, and tomato seedlings by the application rate of 40 ppm (110.9 µM and 126.5 µM, respectively). Taken together, our results suggested that K31565 and K31567 had a potential as a new life environmental algicide for solving an algal problems in the fields such as the hydroponic culture in smart farm, aquarium, municipal agriculture, ecology exhibition hall, etc.

Figures & Tables

Fig. 1. Biological activities of sereoisomers derived from loreclezole against spp. (A, Sce), (B, Ma) and (C, LEMPA) at 9 d, 10 d and 5 d after treatment.