Microbial Degradation of Aromatic hydrocarbon: Naphthalene through Nocardiopsis alba RD3

Abstract

Microorganisms play a vital role incleaning up the environment by degrading the pollutants like monoaromatics andpolycyclic aromatic hydrocarbons(PAHs) which are toxic andare among the most prevalent and persistent pollutants inthe environment. Soil contaminated with petroleum generally contains a mixtureof polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatics. Aromatic compoundsderived from industrial activities often have functional groups such as alkyls, halogens andnitro groups.Naphthalene is a polycyclic aromatic hydrocarbon (PAH) which is persistent in the environment and is toxigenic, carcinogenic and mutagenic that has motivated scientists in putting efforts to remove it from the environment. Incomplete combustion of fossil fuels releases them into the environment thereby polluting it. Bioremediation is one of the natural processes that help to remove xenobiotic compounds from the environment with the help of microorganisms. The aim of our study is to isolate some potential microbial agents to degrade naphthalene into non-hazardous or less hazardous derivatives.A bacterial strainwas isolated from oil contaminated soil of Guwahati Refinery, labeled as RD3, and later identified as Nocardiopsis alba,was found tolerant to naphthalene in culture media and wasable to degrade the naphthalene into its derivatives.The productsthat were detected in naphthalene culture broth were identified mainly as acetic acid andphthalic acid. However, the ring fission products,2-dodecan-1-yl-succinic anhydride and octadec-9-enoic acid were also detected as transformation products, which confirmed the degradation of naphthalene by the bacterial strain.