Isolation and purification techniques for benthic marine cyanobacteria : biotechnology potential

The difficulty often encountered in the generating of axenic cultures is commonly known and well reflected by the great variety of purification methods used. Although numerous techniques have been described, most of them have usually failed or were not suitable for all cultures. Differential gel electrophoresis and Percoll gradient centrifugation, applied by us, appear to be more effective than some other methods in reducing the number of microbial contaminants present in freshly isolated cultures of cyanobacteria from marine environments. The biotechnological potential lies in the working hypothesis that secondary metabolites in mixed cultures may differ markedly from those of axenic cyanobacteria and chemoorganotrophs, respectively.