Degradation of 2,4,6-trinitrotoluene (TNT), a nitroaromatic explosive found in the soil and ground water, was investigated using Pseudomonas aeruginosa in in vitro experiments . Biodegradable abilitiy of this bacteria was performed with 50 and 75 mg L −1 TNT concentrations in a defined liquid medium for 96 h time period. Treatment of TNT in supernatant samples taken at 0, 6, 12, 24, 48, 72 and 96 h from agitated vessels was followed by reverse-phase high-performance liquid chromatography (HPLC). In cultures supplemented with 50 and 75 mgL −1 TNT, after 96 h of incubation 46% and 59% reduction were detected respectively. Two metabolites as degradation intermediates with nitrite release into the medium, 2,4-dinitrotoluene (2,4-DNT) and 4-aminodinitrotoluene (4-ADNT), were elucidated by thin layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS). These findings clearly indicate that Pseudomonas aeruginosa can be used in bioremediation of TNT contaminated sites.

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Identification and multiple antibiotic resistances of amphicillin, chloramphenicol, streptomycin and tetracycline resistant gram-negative bacteria that isolated microorganisms from Gölbaşı and Azaplı lakes (Adiyaman) were investigated in this study. Seasonally taken isolates of totally 386 bacteria in 10 different species from 7 genera were scanned against 16 antibiotics [gentamycin, imipenem, kanamycin, chloramphenicol, meropenem, nalidixic acid, nitrofurantoin, penicillin, cephalothin, cefazolin, cefpirome, ceftizoxime, cefuroxime, streptomycin, tetracycline and trimethoprim-sulphamethoxazole (Bioanalyse)] by using the disc diffusion method to determine the prevalence of multiple antibiotic resistance. Multiple antibiotic resistance of stations showed seasonal changes between 0.29 and 0.91. In generally, multiple antibiotic resistance in Golbasi and Azapli lakes were higher than the reference value and highest multiple antibiotic resistance values were obtained at summer season (3th period). When the obtained data are considered, high multiple antibiotic resistance poses a risk in terms of public health and for economically important animals.

In this study, physicochemical parameters such as total dissolved solids (TDS), pH, temperature, and electrical conductivity (EC) and antibiotic resistance profiles of Escherichia coli isolated from surface waters of 5 different stations of the Atatürk Dam in Adıyaman were investigated. It was found that the water was of good quality in terms of total dissolved solids and electrical conductivity. It shows alkaline properties in regard to pH values. In terms of temperature values, it is of fourth-class quality. Seventy E. coli strains were isolated as an indicator of fecal contamination. In isolated E. coli, antibiotic resistance was determined as 95% for erythromycin, 31.42% for ceftaroline, 30% for cefazolin, 14.28% for tertacycline, 8.50% for chloramphenicol, 4.28% for cefuroxine, and 2.85% for both safotaxime and cefepime. Multiple antibiotic resistance (MAR) rates of 85.71% of bacteria isolated from Sitilce station and 50% of bacteria isolated from Eğri stream station were found to be greater than 0.2. MAR indexes of all bacteria isolated from Kahta, Gerger, and Samsat stations were found to be lower than or equal to 0.2. The results indicated that surface waters of Eğri stream and Sitilce regions may be discharge points of domestic and industrial wastewaters.