Production and characterization of antimicrobial active substance from the cyanobacterium Nostoc muscorum

In this investigation, the cyanobacterium Nostoc muscorum exhibited antagonistic activity against Gram-positive and Gram-negative bacteria and filamentous fungi. The results indicated that the active substance produced maximally after 12 days of incubation in shaken culture at 35 degrees C, at pH 8.0 in BG-I I medium. The increase in nitrate concentration of the medium led to an increase in the antimicrobial production. Chloroform was the best solvent for extracting the active material. The antagonistic material was purified using thin layer chromatography. The compound showed maximum absorption at 240 nm, Infrared (IR) and nuclear magnetic resonance (NMR) indicated presence of gamma OH, gamma CH aromatic, gamma CH aliphatic, gamma C equivalent to N, gamma C=O, gamma C=C and C-O. Mass spectroscopy indicated that its molecular weight is 279. The results also indicated that the compound is phenolic compound. (c) 2005 Elsevier B.V. All rights reserved.