Two Antibiotics (Lavendulin and Actinorubin) Produced by Two Strains of Actinomyces. III. Toxicity and Therapeutic Studies. ∗

Abstract

Summary

The toxic doses (LD₁₀₀) of actinorubin and lavendulin have been determined for white mice by intraperitoneal injection. In the case of lavendulin it was 0.5 mg, while in the case of actinorubin it was 1.37 mg. The ability of the antibiotics to protect mice from death following the intraperitoneal injection of 100 to 1000 M.L.D. of K. pneumoniae was determined. In the case of lavendulin this therapeutic dose was 25 μg and in the case of actinorubin it was found to be 13.7 μg in one experiment. In a second experiment 0.68 mg of actinorubin killed 50%percnt; of the mice while 30 μg protected 50%percnt; of the mice against 100 lethal doses of K. pneumoniae. Further testing of the 2 antibiotics has not been possible due to the limited supplies of the substances.