Biodegradation of nonylphenols, determination of degradation products and detection of responsible microorganisms using molecular techniques

Kara Murdoch, Fadime
Nonylphenol(poly)ethoxylates (NPnEO) have received special attention during the last decades due to their toxic and endocrine-disrupting effects for many organisms. They have limited degradation in wastewater treatment plants especially in activated sludge units. Since they accumulate in sludge, understanding of their fate during sludge treatment is important. With this motivation, this research aimed to monitor the degradation of nonylphenol diethoxylate (NP2EO, as a parent compound) into its degradation products, nonylphenol monoethoxylate (NP1EO) and nonylphenol (NP), in lab-scale semi-continuous anaerobic digesters. Determination and quantification of the degradation products were carried out with gas chromatography-mass spectrometry (GC/MS). Fluorescence in situ hybridization (FISH) and quantitative PCR (qPCR) were used to determine the abundance and composition of four sub-groups of Proteobacteria and acetoclastic methanogens in the total microbial community of anaerobic digesters in the presence and absence of NP2EO. Moreover, enrichment studies were performed in order to isolate diverse bacterial strains able to use branched NP as the sole carbon and energy source. Results showed that NP2EO degraded slowly under anaerobic conditions and NP accumulated as a final product in digesters. Digester performance monitored by solids reduction, chemical oxygen demand (COD) removal and methane production showed no deterioration due to NP2EO spike. Beta- and Gammaproteobacteria constituted the predominant sub-groups of Proteobacteria within the NP2EOspiked sludge community of anaerobic digesters according to FISH and qPCR results. The dominant proliferation of the Methanosaeta (62.5-77%) member of acetoclastic methanogens was determined in the all operated anaerobic digesters.


Biotransformation of Nonylphenol Diethoxylate in anaerobic digesters: Accumulation of metabolites and their effects on digester performance
Murdoch, Fadime Kara; Sanin, Faika Dilek (Elsevier BV, 2016-05-01)
Nonylphenol(poly)ethoxylates (NPnEOs) have caused great concern over the last few decades due to their lipophilic, hydrophobic, and toxic properties. NPnEOs can be degraded to a certain extent in wastewater treatment plants; however since they accumulate in sludge, understanding their influence on digester performance and their fate become important, especially in regards to land application of biosolids. In this respect, the biotransformation of nonylphenol diethoxylate (NP2EO), an accumulative metabolite ...
Covalent immobilization of alpha-amylase onto poly(2-hydroxyethyl methacrylate) and poly(styrene-2-hydroxyethyl methacrylate) microspheres and the effect of Ca2+ ions on the enzyme activity
Tumturk, H; Aksoy, S; Hasırcı, Nesrin (2000-02-01)
alpha-Amylase (1,4-alpha-D-glucan-glucanohydrolase; EC, Type VI-B from porcine pancreas, extra pure 29 units mg(-1)) was covalently immobilized on poly (2-hydroxyethyl methacrylate), p(HEMA), and poly (styrene-2-hydroxyethyl methacrylate), p(St-HEMA) microspheres, which were activated by using epichlorohydrin (ECH). The properties of the immobilized enzyme were investigated and compared with those of the free enzyme. For the assays carried out at 25 degrees C and pH 6.9, the relative activities were...
Crosslinking of Trimethylene Carbonate and D,L-Lactide (Co-) Polymers by Gamma Irradiation in the Presence of Pentaerythritol Triacrylate
Bat, Erhan; Feijen, Jan; Grijpma, Dirk W. (Wiley, 2011-07-07)
High-molecular-weight (co) polymers of trimethylene carbonate and D, L-lactide are efficiently crosslinked using PETA during gamma irradiation. Form-stable networks with gel contents of 86 +/- 5 to 96 +/- 1 are obtained from non-crystalline (co) polymers. Glass transition temperatures and elastic moduli of the networks can be varied by adjusting the copolymer composition. The PETA-containing (co) polymer networks are not cytotoxic. Upon incubation in macrophage cultures for 14 d, all (co) polymer films and ...
Seasonal variability of the Caspian Sea three-dimensional circulation, sea level and air-sea interaction
Ibrayev, R. A; Ozsoy, E; Schrum, C.; Sur, H. I. (Copernicus GmbH, 2010-3-3)
<jats:p>Abstract. A three-dimensional primitive equation model including sea ice thermodynamics and air-sea interaction is used to study seasonal circulation and water mass variability in the Caspian Sea under the influence of realistic mass, momentum and heat fluxes. River discharges, precipitation, radiation and wind stress are seasonally specified in the model, based on available data sets. The evaporation rate, sensible and latent heat fluxes at the sea surface are computed interactively through an atmo...
Illitization of Late Devonian-Early Carboniferous K-bentonites from Western Pontides, NW Turkey: Implications for their origin and age
BOZKAYA, ÖMER; Günal Türkmenoğlu, Asuman; Göncüoğlu, Mehmet Cemal; Unluce, Ozge; Yılmaz, İsmail Ömer; Schroeder, Paul A. (2016-12-01)
K-bentonite (tephra) layers are exposed as thin beds within Late Devonian-Early Carboniferous carbonates of the Yilanh formation at four different locations in northwestern, Turkey. Clays separated from K-bentonites in the Gavurpman, Yilanh Burnu (Barth) and Cimsir Cukurlari (Sapca) quarries and the highway tunnel section near Zonguldak were analyzed by X-ray diffraction, optical, scanning and high-resolution transmission electron microscopy and inductively coupled plasma-mass spectrometry. The clay mineral...
Citation Formats
F. Kara Murdoch, “Biodegradation of nonylphenols, determination of degradation products and detection of responsible microorganisms using molecular techniques,” Ph.D. - Doctoral Program, Middle East Technical University, 2015.