TETRANACTIN, A NEW MITICIDAL ANTIBIOTIC

I. ISOLATION, CHARACTERIZATION AND PROPERTIES OF TETRANACTIN

抄録

In our screening for pesticidal antibiotics using Azuki-bean weevil as a test insect, a new antibiotic, tetranactin, was isolated as crystalline rhombic prisms from the filter cake of the fermented broth of Streptomyces aureus strain S-3466. Tetranactin shows significant insecticidal activity against Azuki-bean weevil by the topical application method but lucks the activity by the film contact method. The adults of carmine mite are highly sensitive to the antibiotic, since LC₅₀ for the mite is 9 ppm bythe spray method. The antibiotic inhibits the growth of gram-positive bacteria and some phytopathogenic fungi in vitro at low concentrations. Acute toxicity of tetranactin is low ; mice tolerated an intraperitoneal administration of 300 mg/kg and an oral administration of 15, 000 mg/kg.