2000 年 48 巻 10 号 p. 1442-1446
A new chitinase inhibitor, designated as argadin (1), was isolated form the cultured broth of a fungal strain FO-7314. The strain was identified as Clonostachys sp. from the morphological characteristics. Argadin was purified from the cultured mycelium by a combination of cation exchange, adsorption and gel filtration chromatographic methods. The structure of argadin was elucidated as cyclo(Nω-acetyl-L-arginyl-D-prolyl-homoseryl-histidyl-L-2-aminoadipyl) in which homoseryl γ-methylene bonded to histidyl α-amino residue. The IC50 value of argadin against Lucilia cuprina (blowfly) chitinase was 150 nM at 37°C and 3.4 nM at 20°C. Argadin arrested the moult of cockroach larvae upon injection into the ventral abdominal part.
