Carbazomycin B is a bacterial metabolite that has been found inStreptomycesand has diverse biological activities.^1,2,3,4It is active against a panel of seven fungi (MICs = 3.2-200 µg/ml) and a panel of seven bacteria (MICs = 25-50 µg/ml), as well asP. falciparumandC. albicans(IC₅₀s = 2.37 and 19.6 µg/ml, respectively).^1,3It is also active against a panel of five plant pathogenic fungi (MICs = 12.5-200 µg/ml).²Carbazomycin B is cytotoxic to MCF-7, KB, NCI H187, and Vero cells (IC₅₀s = 8.4, 8.6, 4.2, and 48.9 µM, respectively).³It also inhibits 5-lipoxygenase (5-LO) activity in RBL-1 cell extracts (IC₅₀= 1.5 µM).⁴

1.Sakano, K.-I., Ishimaru, K., and Nakamura, S.New antibiotics, carbazomycins A and B. I. Fermentation, extraction, purification and physico-chemical and biological propertiesJ Antibiot. (Tokyo)33(7)683-689(1980) 2.Naid, T., Kitahara, T., Kaneda, M., et al.Carbazomycins C, D, E and F, minor components of the carbazomycin complexJ. Antibiot. (Tokyo)40(2)157-164(1987) 3.Intaraudom, C., Rachtawee, P., Suvannakad, R., et al.Antimalarial and antituberculosis substances from Streptomyces sp. BCC26924Tetrahedron67(39)7593-7597(2011) 4.Hook, D.J., Yacobucci, J.J., O'Connor, S., et al.Identification of the inhibitory activity of carbazomycins B and C against 5-lipoxygenase, a new activity for these compoundsJ. Antibiot. (Tokyo)43(10)1347-1348(1990)