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Ajisha M, Shaima TC, Menon SV, Kunhi AAM. Bioaugmentation of Soil with Pseudomonas monteilii Strain Eliminates Inhibition of Okra (Abelmoschus esculentus) Seed Germination by m-Cresol. Curr Microbiol 2021; 78:1892-1902. [PMID: 33787977 DOI: 10.1007/s00284-021-02438-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 03/01/2021] [Indexed: 11/29/2022]
Abstract
Cresols are ubiquitous in nature due to their bulk production and end uses in various industrial processes as well as due to their natural presence. They are highly toxic to both fauna and flora and are included in the list of priority pollutants. In the present study, the effect of m-cresol on germination of ten different crop seeds was tested and the seeds of okra and eggplant were found to be very sensitive, okra being the most vulnerable. Okra seeds lost its viability in the presence of m-cresol, which was proportionate to its concentration as indicated by the standard 2,3,5-tetrazoliumtrichloride (TTC) test. Marked decrease in protease and amylase activities was observed in germinating seeds exposed to the compound. The inhibitory effect of m-cresol on germination was eliminated effectively by bioaugmentation of the soil with the cresol-degrading Pseudomonas monteilii S-CSR-0014. Normal germination and seedling vigor were obtained when the seeds were sown four and eight days after the soil inoculation with the bacterial cells, whereas the seeds sown immediately did not show proper germination. The inoculated bacterium degraded m-cresol efficiently from the spiked soil and exhibited concomitant growth. It can be concluded that m-cresol-contaminated soils could be effectively bioremediated to render the soil suitable for normal seed germination and healthy seedling growth of sensitive crops.
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Affiliation(s)
- M Ajisha
- SIAS-Centre for Scientific Research, SAFI Institute of Advanced Study (Affiliated to University of Calicut), Rasiya Nagar, Vazhayoor East P.O., Malappuram, Kerala, 673 633, India
| | - T C Shaima
- SIAS-Centre for Scientific Research, SAFI Institute of Advanced Study (Affiliated to University of Calicut), Rasiya Nagar, Vazhayoor East P.O., Malappuram, Kerala, 673 633, India
| | - Soumya V Menon
- SIAS-Centre for Scientific Research, SAFI Institute of Advanced Study (Affiliated to University of Calicut), Rasiya Nagar, Vazhayoor East P.O., Malappuram, Kerala, 673 633, India
| | - A A Mohammad Kunhi
- SIAS-Centre for Scientific Research, SAFI Institute of Advanced Study (Affiliated to University of Calicut), Rasiya Nagar, Vazhayoor East P.O., Malappuram, Kerala, 673 633, India.
- Ayesha Cottage, Door # 6/170, Ashok Nagar, Kasaragod, Kerala, 671 121, India.
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Ribeiro HB, Bampi J, da Silva TC, Dervanoski A, Milanesi PM, Fuzinatto CF, de Mello JMM, da Luz C, Vargas GDLP. Study of phenol biodegradation in different agitation systems and fixed bed column: experimental, mathematical modeling, and numerical simulation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:45250-45269. [PMID: 32789632 DOI: 10.1007/s11356-020-10380-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
Phenol degradation was studied in two different agitation systems in a batc h reactor (mechanical agitation and orbital agitation) and the support of the most efficient system was used for fixed bed bioreactor studies. The support used was coconut shell charcoal. The results showed that the mechanical agitation bioreactor was more effective in phenol removal, due to the amount of biomass adhered to the support (8.56 mg gsupport-1), running at approximately 100% of the phenol biodegradation in 300 min. The toxicity analysis of the waters was moderate, because the EC50,48h values in the analyzed samples are higher than 50%. Within the experimental data obtained from the batch system, it was possible to find the parameters of the kinetic model of Michaelis-Menten, which was used to simulate the bioreactor in a fixed bed. A mathematical model of a one-equation, which considers the effects of dispersion, convection, and reaction in the liquid phase, and diffusion and reaction inside the biofilm was used and the results obtained through numerical simulation were compared with the experimental results of the bioreactor in a fixed bed, and new operational conditions in the bed were simulated with good accuracy.
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Affiliation(s)
- Heraldo Baialardi Ribeiro
- Post-Graduate Program in Science and Environmental Technology, Federal University of Fronteira Sul, ERS 135-Km 72, No 200, PO Box 764, Erechim, RS, 99700-970, Brazil
| | - Josiane Bampi
- Environmental and Sanitary Engineering Department, Federal University of Fronteira Sul, ERS 135-Km 72, No 200, PO Box 764, Erechim, RS, 99700-970, Brazil
| | - Taina Cristini da Silva
- Environmental and Sanitary Engineering Department, Federal University of Fronteira Sul, ERS 135-Km 72, No 200, PO Box 764, Erechim, RS, 99700-970, Brazil
| | - Adriana Dervanoski
- Environmental and Sanitary Engineering Department, Federal University of Fronteira Sul, ERS 135-Km 72, No 200, PO Box 764, Erechim, RS, 99700-970, Brazil.
| | - Paola Mendes Milanesi
- Agronomy Department, Federal University of Fronteira Sul, ERS 135-Km 72, No 200, PO Box 764, Erechim, RS, 99700-970, Brazil
| | - Cristiane Funghetto Fuzinatto
- Environmental and Sanitary Engineering Department, Federal University of Fronteira Sul, ERS 135-Km 72, No 200, PO Box 764, Erechim, RS, 99700-970, Brazil
| | - Josiane Maria Muneron de Mello
- Post-Graduate Program in Environmental Sciences, Post-Graduate Program in Technology and Management of the Innovation, Universidade Comunitária da Região de Chapecó - Unochapecó, Chapecó, Brazil
| | - Cleuzir da Luz
- Post-Graduate Program in Food Science and Technology, University of Santa Catarina State, BR 282 km 573, Pinhalzinho, SC, 89870-000, Brazil
| | - Gean Delise Leal Pasquali Vargas
- Post-Graduate Program in Science and Environmental Technology, Federal University of Fronteira Sul, ERS 135-Km 72, No 200, PO Box 764, Erechim, RS, 99700-970, Brazil
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Okcu GD, Okten HE, Yalcuk A. A hybrid process for 2,4-dichlorophenoxy acetic acid herbicidal treatment and its microbial identification by MALDI-TOF mass spectrometry. ENVIRONMENTAL TECHNOLOGY 2020; 41:764-776. [PMID: 30092741 DOI: 10.1080/09593330.2018.1510433] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 08/05/2018] [Indexed: 06/08/2023]
Abstract
The feasibility of coupling photocatalysis and a biological treatment to remove a herbicide - 2,4-dichlorophenoxy acetic acid (2,4-D) - from pure water was examined using batch experiments following three protocols: aerated (A-BR) and non-aerated biodegradation (NA-BR) alone, and intimately combined photodegradation and biodegradation (P-B). In view of a subsequent biological treatment, 15 and 180 min irradiation times were chosen in accordance with spectrophotometric and LC-MS/MS results that indicated the decrease in the COD/TOC ratio during photocatalysis. Pre-treatment led to a quick decrease in concentration of 2,4-D and COD during the biological process: a 78.79 ± 0.30% COD removal and 38.23 ± 3.12% 2,4-D elimination was measured after 5760 min in A-BR, and 80.89 ± 0.81% COD and 81.36 ± 1.37% 2,4-D removal was achieved after 2880 min in P-B. For species identification using matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF)-TOF/MS equipment, Aeromonas eucrenophila, Stenotrophomonas acidaminiphila, Ralstonia pickettii, Sphingobacterium multivorum and Acinetobacter towneri were identified with high accuracy, and they play important roles in the degradation of 2,4-D.
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Affiliation(s)
- Gamze Dogdu Okcu
- Department of Environmental Engineering, Abant Izzet Baysal University, Bolu, Turkey
| | - Hatice Eser Okten
- Department of Environmental Engineering, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Arda Yalcuk
- Department of Environmental Engineering, Abant Izzet Baysal University, Bolu, Turkey
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González AJ, Fortunato MS, Papalia M, Radice M, Gutkind G, Magdaleno A, Gallego A, Korol SE. Selection and identification of a bacterial community able to degrade and detoxify m-nitrophenol in continuous biofilm reactors. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2015; 122:245-251. [PMID: 26283285 DOI: 10.1016/j.ecoenv.2015.07.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 07/22/2015] [Accepted: 07/24/2015] [Indexed: 06/04/2023]
Abstract
Nitroaromatics are widely used for industrial purposes and constitute a group of compounds of environmental concern because of their persistence and toxic properties. Biological processes used for decontamination of nitroaromatic-polluted sources have then attracted worldwide attention. In the present investigation m-nitrophenol (MNP) biodegradation was studied in batch and continuous reactors. A bacterial community able to degrade the compound was first selected from a polluted freshwater stream and the isolates were identified by the analysis of the 16S rRNA gene sequence. The bacterial community was then used in biodegradation assays. Batch experiments were conducted in a 2L aerobic microfermentor at 28 °C and with agitation (200 rpm). The influence of abiotic factors in the biodegradation process in batch reactors, such as initial concentration of the compound and initial pH of the medium, was also studied. Continuous degradation of MNP was performed in an aerobic up-flow fixed-bed biofilm reactor. The biodegradation process was evaluated by determining MNP and ammonium concentrations and chemical oxygen demand (COD). Detoxification was assessed by Vibrio fischeri and Pseudokirchneriella subcapitata toxicity tests. Under batch conditions the bacterial community was able to degrade 0.72 mM of MNP in 32 h, with efficiencies higher than 99.9% and 89.0% of MNP and COD removals respectively and with concomitant release of ammonium. When the initial MNP concentration increased to 1.08 and 1.44 mM MNP the biodegradation process was accomplished in 40 and 44 h, respectively. No biodegradation of the compound was observed at higher concentrations. The community was also able to degrade 0.72 mM of the compound at pH 5, 7 and 9. In the continuous process biodegradation efficiency reached 99.5% and 96.8% of MNP and COD removal respectively. The maximum MNP removal rate was 37.9 gm(-3) day(-1). Toxicity was not detected after the biodegradation process.
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Affiliation(s)
- Ana J González
- Cátedra de Higiene y Sanidad. Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina.
| | - María S Fortunato
- Cátedra de Higiene y Sanidad. Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina
| | - Mariana Papalia
- Laboratorio de Resistencia Bacteriana. Cátedra de Microbiología, Facultad de Farmacia y Bioquímica. Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina
| | - Marcela Radice
- Laboratorio de Resistencia Bacteriana. Cátedra de Microbiología, Facultad de Farmacia y Bioquímica. Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina
| | - Gabriel Gutkind
- Laboratorio de Resistencia Bacteriana. Cátedra de Microbiología, Facultad de Farmacia y Bioquímica. Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina
| | - Anahí Magdaleno
- Cátedra de Higiene y Sanidad. Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina
| | - Alfredo Gallego
- Cátedra de Higiene y Sanidad. Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina
| | - Sonia E Korol
- Cátedra de Higiene y Sanidad. Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Ciudad Autónoma de Buenos Aires, Argentina
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Biodegradation of P-Cresol by Mixed Culture in Batch Reactor – Effect of the Three Nitrogen Sources Used. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.proeng.2012.01.1225] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Relevance of the Luong model to describe the biodegradation of phenol by mixed culture in a batch reactor. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0294-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Wang P, Qu Y, Zhou J. Changes of microbial community structures and functional genes during biodegradation of phenolic compounds under high salt condition. J Environ Sci (China) 2009; 21:821-826. [PMID: 19803089 DOI: 10.1016/s1001-0742(08)62347-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The changes of microbial community structures and functional genes during the biodegradation of single phenol and phenol plus p-cresol under high salt condition were explored. It was found that the phenol-fed system (PFS) exhibited stronger degrading abilities and more stable biomass than that of the phenol plus p-cresol-fed system (PCFS). The microbial community structures were revealed by a modern DNA fingerprint technique, ribosomal intergenic spacer analysis (RISA). The results indicated that the microbial community of PFS changed obviously when gradually increased phenol concentration, while PCFS showed a little change. 16S rRNA sequence analysis of the major bands showed that Alcanivorax sp. genus was predominant species during phenolic compounds degradation. Furthermore, amplified functional DNA restriction analysis (AFDRA) on phenol hydroxylase genes showed that the fingerprints were substantially different in the two systems, and the fingerprints were not the same during the different operational periods.
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Affiliation(s)
- Ping Wang
- School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, China.
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Gallego A, Gemini VL, Fortunato MS, Dabas P, Rossi SL, Gómez CE, Vescina C, Planes EI, Korol SE. Degradation and detoxification of cresols in synthetic and industrial wastewater by an indigenous strain of Pseudomonas putida in aerobic reactors. ENVIRONMENTAL TOXICOLOGY 2008; 23:664-671. [PMID: 18293406 DOI: 10.1002/tox.20365] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We studied the degradation of mixtures of o-cresol, m-cresol, and p-cresol, by Pseudomonas putida isolated from natural sources, and the application of this degradation to the depuration and detoxification of synthetic and industrial wastewater. Biodegradation assays were performed in batch and continuous-flow fixed-bed aerobic reactors. Biodegradation was evaluated by cresol determination using micellar electrokinetic capillary chromatography, UV spectrophotometry, and chemical oxygen demand (COD). Mineralization of cresols was assessed by gas chromatography performed both at the end of the batch process and in the continuous flow reactor effluent. Microbial growth was measured by the plate count method. Scanning electronic microscopy was employed to observe bacterial cells adsorbed on polyvinyl chloride cylinders in the reactor. Detoxification was evaluated by Vibrio fischeri, Pseudokirchneriella subcapitata, and Daphnia magna toxicity tests. Results obtained show that under batch conditions the strain grew exponentially with 100, 200, and 300 mg/L of each of the isomers in synthetic minimal medium within 48 h; in industrial wastewater with 540 mg/L of cresols similar results were obtained. Removal of cresols and COD was higher than 99.9% and 95.0%, respectively. When assays were performed in continuous flow reactor in synthetic wastewater under operating conditions a removal of total cresols and COD of 99.9% and 96.4%, respectively, was achieved. Results of capillary electrophoresis may suggest a concurrent isomers utilization and simultaneous growth on the substrates. Toxicity was neither detected at the end of the batch process nor in the continuous flow reactor effluent.
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Affiliation(s)
- Alfredo Gallego
- Facultad de Farmacia y BioQuímica, Universidad de Buenos Aires, Junín 956, 4 Piso, CP 1113, Buenos Aires, Argentina
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Singh RK, Kumar S, Kumar S, Kumar A. Biodegradation kinetic studies for the removal of p-cresol from wastewater using Gliomastix indicus MTCC 3869. Biochem Eng J 2008; 40:293-303. [DOI: https:/doi.org/10.1016/j.bej.2007.12.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
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10
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Singh RK, Kumar S, Kumar S, Kumar A. Biodegradation kinetic studies for the removal of p-cresol from wastewater using Gliomastix indicus MTCC 3869. Biochem Eng J 2008. [DOI: 10.1016/j.bej.2007.12.015] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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11
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Ziagova M, Liakopoulou-Kyriakides M. Kinetics of 2,4-dichlorophenol and 4-Cl-m-cresol degradation by Pseudomonas sp. cultures in the presence of glucose. CHEMOSPHERE 2007; 68:921-7. [PMID: 17328941 DOI: 10.1016/j.chemosphere.2007.01.039] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2006] [Revised: 01/15/2007] [Accepted: 01/16/2007] [Indexed: 05/14/2023]
Abstract
Comparison of the ability of Pseudomonas sp. to degrade 2,4-dichlorophenol and 4-Cl-m-cresol in separate cultures in the presence of glucose, as a conventional carbon source, is reported. The specific growth rates at 0.1 mM 2,4-dichlorophenol and 4-Cl-m-cresol were estimated to be 0.181 and 0.154 h(-1), respectively, showing that Pseudomonas sp. is mainly inhibited by 4-Cl-m-cresol. The percentage of consumption ranges between 65% and 11% for 2,4-dichlorophenol and between 37% and 8% for 4-Cl-m-cresol, respectively, depending on its initial concentration. The dechlorination of the two compounds was investigated in the growth media and it was found that chloride liberation in the case of 2,4-dichlorophenol took place during the exponential phase of growth, followed by pH decrease from 6.1 to 5.8 at 0.1 mM. In contrast, in the case of 4-Cl-m-cresol chloride ion release was observed to a lesser extent, indicating the different metabolic pathway of 4-Cl-m-cresol. 2,4-Dichlorophenol and 4-Cl-m-cresol degradation followed a first-order kinetics model, whereas glucose consumption fitted well a zero-order kinetics model.
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Affiliation(s)
- M Ziagova
- Faculty of Chemical Engineering, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
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Bai J, Wen JP, Li HM, Jiang Y. Kinetic modeling of growth and biodegradation of phenol and m-cresol using Alcaligenes faecalis. Process Biochem 2007. [DOI: 10.1016/j.procbio.2006.10.004] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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Corvini PFX, Schäffer A, Schlosser D. Microbial degradation of nonylphenol and other alkylphenols—our evolving view. Appl Microbiol Biotechnol 2006; 72:223-43. [PMID: 16826376 DOI: 10.1007/s00253-006-0476-5] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Revised: 04/11/2006] [Accepted: 04/19/2006] [Indexed: 10/24/2022]
Abstract
Because the endocrine disrupting effects of nonylphenol (NP) and octylphenol became evident, the degradation of long-chain alkylphenols (AP) by microorganisms was intensively studied. Most NP-degrading bacteria belong to the sphingomonads and closely related genera, while NP metabolism is not restricted to defined fungal taxa. Growth on NP and its mineralization was demonstrated for bacterial isolates, whereas ultimate degradation by fungi still remains unclear. While both bacterial and fungal degradation of short-chain AP, such as cresols, and the bacterial degradation of long-chain branched AP involves aromatic ring hydroxylation, alkyl chain oxidation and the formation of phenolic polymers seem to be preferential elimination pathways of long-chain branched AP in fungi, whereby both intracellular and extracellular oxidative enzymes may be involved. The degradation of NP by sphingomonads does not proceed via the common degradation mechanisms reported for short-chain AP, rather, via an unusual ipso-substitution mechanism. This fact underlies the peculiarity of long-chain AP such as NP isomers, which possess highly branched alkyl groups mostly containing a quaternary alpha-carbon. In addition to physicochemical parameters influencing degradation rates, this structural characteristic confers to branched isomers of NP a biodegradability different to that of the widely used linear isomer of NP. Potential biotechnological applications for the removal of AP from contaminated media and the difficulties of analysis and application inherent to the hydrophobic NP, in particular, are also discussed. The combination of bacteria and fungi, attacking NP at both the phenolic and alkylic moiety, represents a promising perspective.
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Affiliation(s)
- P F X Corvini
- Department of Environmental Research, RWTH Aachen University, 52074, Aachen, Germany
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Minamidate W, Tokumura M, Znad HT, Kawase Y. Photodegradation of o-cresol in water by the H2O2/UV process. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2006; 41:1543-58. [PMID: 16835110 DOI: 10.1080/10934520600754722] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Photodegradation of o-cresol in water has been investigated using hydrogen peroxide as an oxidant along with ultra violet lamps. The synergistic effect of H(2)O(2) and UV light was found to be effective to decomposition of o-cresol in water. The effects of wave length of UV light, initial concentration of o-cresol, hydrogen peroxide dose and initial solution pH on photodegradation rate of o-cresol were systematically examined. Degradation of o-cresol with UV-C lamps (wavelength of 254 nm) was more significant than that with near-UV black light lamps (wavelength of 352 nm). The optimal solution pH was around 5 being the natural pH of the solution. The efficiency of o-cresol degradation increased as initial o-cresol concentration decreased. There was the optimal H2O2 dose being around 150 mM when the initial o-cresol concentration was 0.93 mM. Based on the experimental results, a kinetic model for the photodegradation of o-cresol by H(2)O(2)/UV has been developed. The model could simulate the experimental results reasonably.
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Affiliation(s)
- Wataru Minamidate
- Department of Applied Chemistry, Research Center for Biochemical and Environmental Engineering, Toyo University, Saitama 350-8585, Japan
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15
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Håkansson K, Welander U, Mattiasson B. Degradation of acetonitrile through a sequence of microbial reactors. WATER RESEARCH 2005; 39:648-654. [PMID: 15707638 DOI: 10.1016/j.watres.2004.10.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2004] [Revised: 08/26/2004] [Accepted: 10/27/2004] [Indexed: 05/24/2023]
Abstract
Degradation of nitrogen containing organic compounds often leads to formation of ammonium and some low molecular weight organic compounds. The study is focused on degradation of acetonitrile in a sequence of stirred biofilm reactors, where the degradation of acetonitrile into acetic acid and ammonia takes place in the first two reactors. A large fraction of the acetic acid is also degraded in these reactors. The subsequent two reactors were introduced in order to take care of the ammonia, while a fifth reactor was a polishing step before the water was released to the recipient. From earlier studies it is known that the rate of acetonitrile degradation is approximately 80 g acetonitrile/ (m3 reactor h). In the present study nitrification proceeded with 10 g NH4(+)-N/(m3 reactor h) and the denitrification by 35 g NOx(-)-N/ (m3 reactor h). This means that the reactors involved in removal of the nitrogen component needs to be far larger than those dealing with degradation of the more complex molecules.
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Affiliation(s)
- Kristina Håkansson
- Department of Biotechnology, Centre for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
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Mogil?naya OA, Krivomazova ES, Kargatova TV, Lobova TI, Popova LY. Formation of structured communities by natural and transgenic naphthalene-degrading bacteria. APPL BIOCHEM MICRO+ 2005. [DOI: 10.1007/s10438-005-0012-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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