counting and determining the quantiti of naphthalene degrading bacteria in the persian golf

Background and Aim : Persian Gulf has about ۲/۳ of world’s oil reserves. and its marine ecosystem is Seriously in danger because of oil pollution, THERE FORE studying about the statues of Hydrocarbons pollutions so necessary. increase in world oil production consumption caused Environmental pollution And made many serious problems for ecosystem. Asphaltenes, Heterocyclic, Aliphatics and Aromatics are four oil components which are regarded as main chemical pollutants. Aromatic compounds are very toxic and also have carcinogenic and mutagenic effects. So concerns about these compounds are not deniable.Methods : Material and Methods: For isolation of naphthalene-degrading bacteria, marine environmental samples were collected from polluted sites in the Persian Gulf. And with consecutive passage, Naphthalene-degrading bacteria were isolated in ONR۷a medium supplemented with ۲۰۰ ppm of naphthalene .and In order to determine the bacteria growth curve in different concentrations of naphthalene ONR۷a medium was supplemented with various concentrations of naphthalene from۲۰۰ ppm to ۲۰۰۰ ppm. Only one strain could tolerate ۲۰۰۰ppm concentration of naphthalene which is identified Biochemically and molecularly. The naphthalene removal assay was carried out using calibration curve of naphthalene at ۲۷۶ nm by spectrophotometer. Growth curves of the isolates were routinely assessed indirectly by turbidity measurement as (O.D. at ۶۰۰ nm).Results : ۲۳ different strains of Naphthalene-degrading were isolated from marine samples. Most of these strains were gram negative . All selected bacterial strains were grown in ۲۰۰ ppm of naphthalene but by increasing the concentration of naphthalene to ۱۵۰۰ ppm the count falls to ۳ strains. And in ۲۰۰۰ppm only one strain could degrade naphthalene which is chosen as top strain. Molecular identification showed that it’s a Bacillus.Conclusion : This study showed that there are high potent Naphthalene-degrading bacteria in Persian Golf region that can be used in Biological regeneration processes in contaminated areas.