Screening of Myxobacteria and Preliminary Analysis of Its Antibiotic Activity

In order to screen the bioactive compound from Myxobacteria,three strains of Myxobacteria were obtained from dung of hare and rotting wood by means of selective medium,heating treatment and freezing treatment,etc.The antibiotic of the No.1 strain intracellular and exterior was detected by filter paper method.Both the interior and the exterior matter of the No.1 strain had the antibacterial activity,showing different antibiogram.The intracellular matter inhibited both the growth of Gram-positive bac-teria and some Gram-negative bacteria,such as Escherichia coli,but the bacteriostatic activity to Gram-negative bacteria was more powerful.Neither the interior nor exterior matter of the No.1 strain cell inhibits fungus.The antibiotic of the No.1 strain extracellular was isolated by thin-layer chromatography(TLC) and silica gel column chromatography.An anti-Streptomyces microflavus active component was obtained by purification with silica gel column chromatography.