Altemicidin is a monoterpene alkaloid originally isolated from S. sioyaensis with acaricidal and anticancer activities. It is acaricidal to two-spotted spider mites (T. urticae) in a greenhouse pot test at concentrations of 10 and 100 ppm. Altemicidin inhibits the growth of murine L1210 lymphocytic leukemia and IMC carcinoma cells (IC50s=0.84 and 0.82 μg/mL, respectively). It is toxic to mice with an LD50 value of 0.3 mg/kg.
[1] Takahashi, et al. Altemicidin, a new acaricidal and antitumor substance. I. Taxonomy, fermentation, isolation and physico-chemical and biological properties. J. Antibiot. (Tokyo) 42(11), 1556-1561 (1989).
