Mahsa Harirforoush - Department of Biology, Tehran Science and Research Branch, Islamic Azad University, Tehran, Iran
Mahmoud Shavandi - Microbiology and Biotechnology Group, Environment and Biotechnology Research Division, Research Institute of Petroleum Industry, Tehran, Iran
Mohammad Ali Amoozegar - Extremophiles Laboratory, Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran, Iran
Parvaneh Saffarian - Department of Biology, Tehran Science and Research Branch, Islamic Azad University, Tehran, Iran

Background and Aim : Naphthalene is one of the polycyclic aromatic hydrocarbons found inpetroleum, coal and other petrochemical products and can be a very important indicator of thepetroleum originated pollution in the environment. In this study, the microbial diversity and thegenes involved in the naphthalene degradation under anaerobic conditions were investigated, inthe waters of the national protected area of Nayband Gulf.Methods : The DNA was extracted from the Nayband Gulf water sample. The extracted DNAsample was sequenced using Illumina HiSeq ۲۵۰۰ platform (Novogene, Hong Kong), by the nextgenerationsequencing (NGS) technique. QIIME ۲ (version ۲۰۲۲.۲) was used to analyse ۱۶S rRNAgene amplicon sequencing. To predict the functional genes involved in naphthalene degradationunder anaerobic conditions from ۱۶S rRNA gene sequences, we used Phylogenetic Investigationof Communities by Reconstruction of Unobserved States (PICRUSt) (version ۱.۱.۴).Results : Our findings indicate that the most abundant genera in the Nayband Gulf water weremainly affiliated to Spongiibacter (۲۲%) and Alcanivorax (۱۸.۸۶%). It is predicted that thesebacteria have the most prominent metabolic genes coding for naphthalene degradation underanaerobic conditions in their genomes, according to PICRUSt.Conclusion : The results of this study showed that the presence of petrochemical and oil industriesin the Asalouye region has affected the waters of Nayband Gulf and caused oil pollution in thisregion. Oil-contaminated marine environments have been shown to have increased abundance ofbacteria that degrade oil pollutants. Naturally occurring Spongiibacter and Alcanivorax have ahigh ability to break down naphthalene and can be exploited in designing bioremediation strategiesfor treatment of naphthalene contaminated sites.

Naphthalene, NGS, PICRUSt, QIIME ۲, Nayband Gulf