Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

A Study on The Degradation Ability of The Bacteria Isolated from The Sea of Marmara in Polycyclıc Aromatıc Hydrocarbons (Pah)

In this study, the aim was to determine the ability of bacteria isolated from seawater samples collected in 4 stations selected between ports, fishing harbors, oil stations and marinas of Marmara Sea coastal area. Indicator bacteria, total mesophilic aerobic culturable bacteria, nutrients and chlorophyll a analyses were also realized in order to determine bacteriological pollution bacteria abundance and chemical and biological water quality of the stations respectively.

Membrane filtration technique was used for feacal and total coliform analyses of surface seawater samples that were monthly sampled between July 2007 and June 2008. Marine agar and spread culture method was used in order to determine total culturable bacteria abundance. Nutrients and chlorophyll a analyses were carried out by spectrophotometric method. Bacillus subtilis, Serratia marcescens, Enterococcus faecalis, Pseudomonas aeruginosa, Pseudomonas oryzihabitans, Vibrio fluvialis, Esherichia coli, Burkholderia cepacea, Aeromonas hydrophila, Citrobacter frenduii, Providencia sp., Klebsiella ornitholytica, Klebsiella oxytoca, Proteus mirabilis, Enterobacter sakazakii, Eikenella corrodens were selected between a total of 122 isolates were identified by API 20 E and API 50 CHB.. Minimum Inhibition Concentration (MIC) tests were effected on selected species with Batman crude oil obtained from Batman oil refinery. Isolates for which MIC values were determined and mixed cultures of these isolates were incubated in a shaking incubator at 150 rpm during 30 days and the ability of the isolates to degrade oil hydrocarbons was investigated by recording the oil layer thickness and the pH values in 72 hours intervals.

The results show that the studied areas have feacal and total coliform bacteria values higher than national and international limit values. The species E. sakazakii was recorded as the best candidate species between bacteria isolated from the studied area for bioremediation studies followed by single cultures of E. feacalis, E. corrodens and P. aeruginosa and mixed culture of P. aeruginosa+ B. subtilis+E. coli, mixed culture of P. aeruginosa+B. subtilis+V. fluvialis, and mixed culture of K. oxytoca+P. oryzihabitans+ P. mirabilis+E. sakazakii+E. corrodens. Low oil degradation abilities were found for K. oxytoca, A. hydrophila, C. frenduii, Providencia sp., B. cepacea The stocking of bacteria able to degrade oil hydrocarbons constitute basic data for our further studies intended to analytically determine which fractions of the oil was degraded by these bacteria.