Screening and molecular identification of nocardia with ability to biodegradation of Polycyclic Aromatic Hydrocarbons and phenol from Iranian ecosystems

Anthropogenic pollutants are known to have adverse effect on ecosystem, and human health. Biodegradation is an option that has been widely used to remediate organic contaminants and reduce the risk of these hazardous materials. Microorganisms are readily available to screen and can be rapidly characterized to be applied in many extreme environmental conditions. Actinomycetes have a great potential for the production of bioactive secondary metabolites which have biodegradation activity. This study aimed to screen and characterize Nocardia species with biodegradation potential from diverse Iranian ecosystems. The isolates were screened from 90 collected environmental samples, identified and characterized using conventional and molecular microbiological methods including the PCR amplification and sequencing analysis of 16S rRNA and rpoB genetic markers. Growth rate in presence of pollutants, chromatography, Gibbs and turbidometric methods were used to determine bioremediation ability. A total of 19 Nocardia isolates were recovered from the cultured samples (21.1%) that belonged to 10 various species. The most prevalent species was N. farcinica; 4 isolate (21%), followed by N. cyriacigeorgica and N. cashijiensis; 3 isolates each (15.7%) and N. asteroides 2 isolates (10.5%). In this study isolates showed biodegradation activity against PAHs, phenol and oil derivations. Discussion and Our results showed that various Nocardia species isolated from Iranian ecosystems have great potential for biodegradation of environmental contaminant, therefore we can used this bacteria in bioremediation process, although they have not received much attention for such significant usage.