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Öğe Bioattenuation of Detergent Plant Effluents Enhanced via Single Microbial Augmentations(Springer Heidelberg, 2016) Icgen, Bulent; Salih, Salih Batuhan; Goksu, Lale; Ulusoy, Huseyin; Yilmaz, FadimeDue to natural attenuation, anionic detergents in surface waters are not inferred as big environmental issues. However, the effluents from large industrial areas with high detergent concentrations can have significant local impacts. These circumstances can be diminished by using efficient detergent-degrading bacterial isolates through bioaugmentation. In this study, detergent plant effluents were analysed by using a methylene blue active substance assay to determine detergent content during natural attenuation processes, and after single augmentations of 12 anionic detergent-degrading bacterial isolates with high detergent tolerating abilities in batch microcosms. Maximum bioattenuation of detergents was determined as 56 % after 66 h incubation under the conditions that mimicked the natural environment. Bioattenuation was enhanced as much as 83 and 91 % in 78 h incubation time through single microbial augmentations of filter-sterilized and non-sterilized effluents, respectively. Eight Pseudomonas and one Aeromonas species were found to be highly competitive by showing high biodegradation abilities in pure culture experiments as well as enhancing degradation of detergents in both filter-sterilized and non-sterilized effluents through their single augmentations. Although remaining three isolates, namely Pseudomonas fluorescens SDS6, P. resinovorans SDS10-2, and P. corrugata SDS10-3 displayed lower degrading abilities in pure culture experiments than the natural attenuation, they later turned out to be actively enhancing the degradation of detergents during their single augmentations.Öğe Challenging tin toxicity by a novel strain isolated from freshwaters(Taylor & Francis Inc, 2015) Cerit, Semih; Yilmaz, Fadime; Icgen, BulentThe first major challenge for the bioremediation field is to select the most promising types of biomass. Hence, the objective of this study was to isolate and identify a novel species which has the potential to remediate tin in freshwaters. For this reason, a bacterium designated as Sn11, with 59 mu g ml(-1) maximum tolerable concentration of tin was isolated selectively from the freshwater samples collected along the river Kirikkale-Kizilirmak, Turkey. Identification of the isolate was done using biochemical tests, fatty acid methyl ester analysis, and 16S rRNA sequencing. Fatty acids produced by the isolate investigated were assumed as typical for the genus Pantoea. Pantoea were highly homogeneous by dominant C-16:0 and C-16:1 cis 9 fatty acids. 16S rRNA sequence analysis also confirmed that the isolate Sn11 had 98% homology with Pantoea agglomerans. The complete sorption of 59 mu g ml(-1) tin by P. agglomerans was recorded at about 20 h incubation. Due to higher affinity toward tin sorption, P. agglomerans can be an important isolate for the natural attenuation of tin toxicity in contaminated freshwaters.Öğe Characterization of lead-resistant river isolate Enterococcus faecalis and assessment of its multiple metal and antibiotic resistance(Springer, 2013) Aktan, Yasin; Tan, Sema; Icgen, BulentContamination of surface waters has a direct impact on the public health of entire communities. Microorganisms inhabiting contaminated surface waters have developed mechanisms of coping with a variety of toxic metals and drugs. Investigations were carried out to isolate and identify lead-resistant bacteria from the river KA +/- zA +/- lA +/- rmak along the city of KA +/- rA +/- kkale, Turkey. Of the 33 lead-resistant isolates, one isolate with a minimal inhibitory concentration of 1,200 mg L-1 was isolated and identified as Enterococcus faecalis by using biochemical tests and 16S rRNA sequencing. Lead-resistant E. faecalis isolate was found out to be resistant to other heavy metals like aluminum, lithium, barium, chromium, iron, silver, tin, nickel, zinc, and strontium and to drugs like amikacin, aztreonam, and gentamicin. E. faecalis harbored four plasmids with the molecular sizes of 1.58, 3.06, 22.76, and 28.95 kb. Plasmid profile analyses of cured derivatives revealed that the lead resistance ability of E. faecalis was still existing despite the elimination of all the plasmids. Moreover, the antibiotic resistance pattern of the cured derivatives did not demonstrate any change from the parental strain. Our findings indicated that the lead resistance genes of E. faecalis were located on the chromosomal DNA rather than the plasmid.Öğe Higher alkyl sulfatase activity required by microbial inhabitants to remove anionic surfactants in the contaminated surface waters(Iwa Publishing, 2017) Icgen, Bulent; Salik, Salih Batuhan; Goksu, Lale; Ulusoy, Huseyin; Yilmaz, FadimeBiodegradation of anionic surfactants, like sodium dodecyl sulfate (SDS) are challenged by some bacteria through the function of the enzyme alkyl sulfatases. Therefore, identifying and characterizing bacteria capable of degrading SDS with high alkyl sulfatase enzyme activity are pivotal. In this study, bacteria isolated from surfactant contaminated river water were screened for their potential to degrade SDS. Primary screening carried out by the conventional enrichment culture technique and assessment of SDS-degrading ability through methylene blue active substance assay revealed 12, out of 290, SDS-degrading surface water bacteria with maximum SDS degrading abilities of 46-94% in 24-54 h. The isolates exhibited optimum growth at SDS concentration of 1 g/L, but tolerated up to 15-75 g/L. Eleven isolates were identified as the species of Pseudomonas and one isolate was identified as Aeromonas through 16S rRNA sequencing. Proteolytic activity of alkyl sulfatases in the identified isolates was shown by using native-PAGE analysis. The determined enzyme activities changed in between 1.32 and 2.90 U/mg in the crude extracts. Preliminary experiments showed that the isolates with the alkyl sulfatase enzyme activities >= 2.50 U/mg were strong gratuitous degraders. However, their relative importance in soil, sewage, and wastewater treatment plants remains to be assessed.Öğe Multidrug and Heavy Metal-Resistant Raoultella planticola Isolated from Surface Water(Springer, 2013) Koc, Serkan; Kabatas, Burak; Icgen, BulentA surface water isolate of Raoultella sp. having both multidrug- and multimetal-resistant ability was isolated and identified as Raoultella planticola. R. planticola displayed resistance to 15 drugs like ampicillin, amoxicillin/clavulanic acid, aztreonam, erythromycin, imipenem, oxacillin, pefloxacin, penicillin, piperacillin, piperacillin/tazobactam, rifampin, sulbactam/cefoperazone, ticarsillin, ticarsillin/clavulanic acid, vancomycin, and to 11 heavy metals like aluminum, barium, copper, iron, lead, lithium, manganese, nickel, silver, strontium, and tin. The multidrug and multi-metal-resistant R. planticola may remain present in the environment for a long time. Due to a possible health risk of these pathogenic bacteria, a need exists for an accurate assessment of their acquired resistance to multiple drugs and metals.Öğe Surface water isolates of hemolytic and non-hemolytic Acinetobacter with multiple drug and heavy metal resistance ability(Iwa Publishing, 2014) Akbulut, Sevilay; Yilmaz, Fadime; Icgen, BulentAcinetobacter in surface waters are a major concern because of their rapid development of resistance to a wide range of antimicrobials and their ability to persist in these waters for a very long time. Four surface water isolates of Acinetobacter having both multidrug-and multimetal-resistant ability were isolated and identified through biochemical tests and 16S rDNA sequencing. Based on these analyses, two hemolytic isolates were affiliated with Acinetobacter haemolyticus with an accession number of X81662. The other two non-hemolytic isolates were identified as Acinetobacter johnsonii and Acinetobacter calcoaceticus and affiliated with accession numbers of Z93440 and AJ888983, respectively. The antibiotic and heavy metal resistance profiles of the isolates were determined by using 26 antibiotics and 17 heavy metals. Acinetobacter isolates displayed resistance to beta-lactams, cephalosporins, aminoglycosides, and sulfonamides. The hemolytic isolates were found to show resistance to higher numbers of heavy metals than the non-hemolytic ones. Due to a possible health risk of these pathogenic bacteria, a need exists for an accurate assessment of their acquired resistance to multiple drugs and metals.Öğe Surface Water-Borne Multidrug and Heavy Metal-Resistant Staphylococcus Isolates Characterized by 16S rDNA Sequencing(Springer, 2013) Yilmaz, Fadime; Orman, Nazli; Serim, Gamze; Kochan, Ceren; Ergene, Aysun; Icgen, BulentFour Staphylococcus isolates having both multidrug- and multimetal-resistant ability were isolated from surface water. Further identification of the isolates was obtained through biochemical tests and 16S rDNA gene sequencing. One methicillin-resistant and two methicilin-sensitive isolates were determined as Staphylococcus aureus. The other isolate was identified as Staphylococcus warneri. The antibiotic and heavy metal resistance profiles of the Staphylococcus isolates were determined by using 26 antibiotics and 17 heavy metals. S. aureus isolates displayed resistance to most of the beta-lactam antibiotics tested. All Staphylococcus isolates were resistant to heavy metals including silver, lithium, and barium. Due to a possible health risk of these pathogenic bacteria, a need exists for an accurate assessment of their acquired resistance to multiple drugs and metals.
