Journal articles: 'Naphthalene Salicylic acid Environmental degradation'

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Kuiper, Irene, Lev V. Kravchenko, Guido V. Bloemberg, and Ben J. J. Lugtenberg. "Pseudomonas putida Strain PCL1444, Selected for Efficient Root Colonization and Naphthalene Degradation, Effectively Utilizes Root Exudate Components." Molecular Plant-Microbe Interactions® 15, no. 7 (2002): 734–41. http://dx.doi.org/10.1094/mpmi.2002.15.7.734.

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Previously, we have described the selection of a plant-bacterium pair that is efficient in rhizoremediating naphthalene pollution in microcosm studies. After repeated selection for efficient root tip colonization upon inoculation of seeds of grass cv. Barmultra and for stable and efficient growth on naphthalene, Pseudomonas putida PCL1444 was selected as the most efficient colonizer of Barmultra roots. Here, we report the analysis of Barmultra root exudate composition and our subsequent tests of the growth rate of the bacterium and of the expression of the naphthalene degradation genes on individual exudate components. High performance liquid chromatography analysis of the organic acid and sugar root-exudate components revealed that glucose and fructose are the most abundant sugars, whereas succinic acid and citric acid are the most abundant organic acids. Tn5luxAB mutants of PCL1444 impaired in naphthalene degradation appeared to be impaired in genes homologous to genes of the upper naphthalene degradation pathway present in various Pseudomonas strains and to genes of the lower pathway genes for naphthalene degradation in P. stutzeri. Highest expression for both pathways involved in naphthalene degradation during growth in minimal medium with the carbon source to be tested was observed at the start of the logarithmic phase. Naphthalene did not induce the upper pathway, but a different pattern of expression was observed in the lower pathway reporter, probably due to the conversion of naphthalene to salicylic acid. Salicylic acid, which is described as an intermediate of the naphthalene degradation pathway in many Pseudomonas strains, did induce both pathways, resulting in an up to sixfold higher expression level at the start of the logarithmic phase. When expression levels during growth on the different carbon sources present in root exudate were compared, highest expression was observed on the two major root exudate components, glucose and succinic acid. These results show an excellent correlation between successful naphthalene rhizoremediation by the Barmultra-P. putida PCL1444 pair and both efficient utilization of the major exudate components for growth and high transcription of the naphthalene catabolic genes on the major exudate components. Therefore, we hypothesize that efficient root colonizing and naphthalene degradation is the result of the applied colonization enrichment procedure.

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Chowdhury, Piyali Pal, Jayita Sarkar, Soumik Basu, and Tapan K. Dutta. "Metabolism of 2-hydroxy-1-naphthoic acid and naphthalene via gentisic acid by distinctly different sets of enzymes in Burkholderia sp. strain BC1." Microbiology 160, no. 5 (2014): 892–902. http://dx.doi.org/10.1099/mic.0.077495-0.

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Burkholderia sp. strain BC1, a soil bacterium, isolated from a naphthalene balls manufacturing waste disposal site, is capable of utilizing 2-hydroxy-1-naphthoic acid (2H1NA) and naphthalene individually as the sole source of carbon and energy. To deduce the pathway for degradation of 2H1NA, metabolites isolated from resting cell culture were identified by a combination of chromatographic and spectrometric analyses. Characterization of metabolic intermediates, oxygen uptake studies and enzyme activities revealed that strain BC1 degrades 2H1NA via 2-naphthol, 1,2,6-trihydroxy-1,2-dihydronaphthalene and gentisic acid. In addition, naphthalene was found to be degraded via 1,2-dihydroxy-1,2-dihydronaphthalene, salicylic acid and gentisic acid, with the putative involvement of the classical nag pathway. Unlike most other Gram-negative bacteria, metabolism of salicylic acid in strain BC1 involves a dual pathway, via gentisic acid and catechol, with the latter being metabolized by catechol 1,2-dioxygenase. Involvement of a non-oxidative decarboxylase in the enzymic transformation of 2H1NA to 2-naphthol indicates an alternative catabolic pathway for the bacterial degradation of hydroxynaphthoic acid. Furthermore, the biochemical observations on the metabolism of structurally similar compounds, naphthalene and 2-naphthol, by similar but different sets of enzymes in strain BC1 were validated by real-time PCR analyses.

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Meckenstock, Rainer U., Eva Annweiler, Walter Michaelis, Hans H. Richnow, and Bernhard Schink. "Anaerobic Naphthalene Degradation by a Sulfate-Reducing Enrichment Culture." Applied and Environmental Microbiology 66, no. 7 (2000): 2743–47. http://dx.doi.org/10.1128/aem.66.7.2743-2747.2000.

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ABSTRACT Anaerobic naphthalene degradation by a sulfate-reducing enrichment culture was studied by substrate utilization tests and identification of metabolites by gas chromatography-mass spectrometry. In substrate utilization tests, the culture was able to oxidize naphthalene, 2-methylnaphthalene, 1- and 2-naphthoic acids, phenylacetic acid, benzoic acid, cyclohexanecarboxylic acid, and cyclohex-1-ene-carboxylic acid with sulfate as the electron acceptor. Neither hydroxylated 1- or 2-naphthoic acid derivatives and 1- or 2-naphthol nor the monoaromatic compounds ortho-phthalic acid, 2-carboxy-1-phenylacetic acid, and salicylic acid were utilized by the culture within 100 days. 2-Naphthoic acid accumulated in all naphthalene-grown cultures. Reduced 2-naphthoic acid derivatives could be identified by comparison of mass spectra and coelution with commercial reference compounds such as 1,2,3,4-tetrahydro-2-naphthoic acid and chemically synthesized decahydro-2-naphthoic acid. 5,6,7,8-Tetrahydro-2-naphthoic acid and octahydro-2-naphthoic acid were tentatively identified by their mass spectra. The metabolites identified suggest a stepwise reduction of the aromatic ring system before ring cleavage. In degradation experiments with [1-13C]naphthalene or deuterated D8-naphthalene, all metabolites mentioned derived from the introduced labeled naphthalene. When a [13C]bicarbonate-buffered growth medium was used in conjunction with unlabeled naphthalene, 13C incorporation into the carboxylic group of 2-naphthoic acid was shown, indicating that activation of naphthalene by carboxylation was the initial degradation step. No ring fission products were identified.

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Foght, J. M., and D. W. S. Westlake. "Expression of dibenzothiophene-degradative genes in two Pseudomonas species." Canadian Journal of Microbiology 36, no. 10 (1990): 718–24. http://dx.doi.org/10.1139/m90-121.

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The genes encoding dibenzothiophene (DBT) degradation in Pseudomonas alcaligenes strain DBT2 were cloned into plasmid pC1 by other workers. This plasmid was conjugally transferred into a spontaneous variant of Pseudomonas sp. HL7b (designated HL7bR) incapable of oxidizing DBT (Dbt− phenotype). Acquisition of plasmid pC1 simultaneously restored oxidation of DBT and naphthalene to the transconjugant, although the primary DBT metabolite produced by transconjugant HL7bR(pC1) corresponded to that produced by wild-type strain DBT2 rather than that from wild-type strain HL7b. Inducers of the naphthalene pathway (naphthalene, salicylic acid, and 2-aminobenzoate) stimulated DBT oxidation in transconjugant HL7bR(pC1) when present at 0.1 mM concentrations but had no effect on wild-type strain HL7b. Higher concentrations (5 mM) of salicylic acid and naphthalene were inhibitory to DBT oxidation in all strains. DNA–DNA hybridization was not observed between plasmid pC1 and genomic DNA from strains HL7b or HL7bR, nor between authentic naphthalene-degradative genes (plasmid NAH2) and either plasmid pC1 or strain HL7b, despite the observation that the degradative genes encoded on plasmid pC1 functionally resembled broad-specificity naphthalene-degradative genes. Transconjugant HL7bR(pC1) is a mosaic of the parental types regarding DBT metabolite production, regulation, and use of carbon sources. Key words: dibenzothiophene, naphthalene, degradation, regulation, hybridization.

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Poonthrigpun, Siriwat, Kobchai Pattaragulwanit, Sarunya Paengthai, et al. "Novel Intermediates of Acenaphthylene Degradation by Rhizobium sp. Strain CU-A1: Evidence for Naphthalene-1,8-Dicarboxylic Acid Metabolism." Applied and Environmental Microbiology 72, no. 9 (2006): 6034–39. http://dx.doi.org/10.1128/aem.00897-06.

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ABSTRACT The acenaphthylene-degrading bacterium Rhizobium sp. strain CU-A1 was isolated from petroleum-contaminated soil in Thailand. This strain was able to degrade 600 mg/liter acenaphthylene completely within three days. To elucidate the pathway for degradation of acenaphthylene, strain CU-A1 was mutagenized by transposon Tn5 in order to obtain mutant strains deficient in acenaphthylene degradation. Metabolites produced from Tn5-induced mutant strains B1, B5, and A53 were purified by thin-layer chromatography and silica gel column chromatography and characterized by mass spectrometry. The results suggested that this strain cleaved the fused five-membered ring of acenaphthylene to form naphthalene-1,8-dicarboxylic acid via acenaphthenequinone. One carboxyl group of naphthalene-1,8-dicarboxylic acid was removed to form 1-naphthoic acid which was transformed into salicylic acid before metabolization to gentisic acid. This work is the first report of complete acenaphthylene degradation by a bacterial strain.

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Goi, A., Y. Veressinina, and M. Trapido. "Degradation of salicylic acid by Fenton and modified Fenton treatment." Chemical Engineering Journal 143, no. 1-3 (2008): 1–9. http://dx.doi.org/10.1016/j.cej.2008.01.018.

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Xu, Peng, Wencheng Ma, Hongjun Han, Baolin Hou, and Shengyong Jia. "Characterization of naphthalene degradation by Streptomyces sp. QWE-5 isolated from active sludge." Water Science and Technology 70, no. 6 (2014): 1129–34. http://dx.doi.org/10.2166/wst.2014.356.

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A bacterial strain, QWE-5, which utilized naphthalene as its sole carbon and energy source, was isolated and identified as Streptomyces sp. It was a Gram-positive, spore-forming bacterium with a flagellum, with whole, smooth, convex and wet colonies. The optimal temperature and pH for QWE-5 were 35 °C and 7.0, respectively. The QWE-5 strain was capable of completely degrading naphthalene at a concentration as high as 100 mg/L. At initial naphthalene concentrations of 10, 20, 50, 80 and 100 mg/L, complete degradation was achieved within 32, 56, 96, 120 and 144 h, respectively. Kinetics of naphthalene degradation was described using the Andrews equation. The kinetic parameters were as follows: qmax (maximum specific degradation rate) = 1.56 h−1, Ks (half-rate constant) = 60.34 mg/L, and KI (substrate-inhibition constant) = 81.76 mg/L. Metabolic intermediates were identified by gas chromatography and mass spectrometry, allowing a new degradation pathway for naphthalene to be proposed. In this pathway, monooxygenation of naphthalene yielded naphthalen-1-ol. Further degradation by Streptomyces sp. QWE-5 produced acetophenone, followed by adipic acid, which was produced as a combination of decarboxylation and hydroxylation processes.

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Lu, Yi Chen, Shuang Zhang, and Hong Yang. "Acceleration of the herbicide isoproturon degradation in wheat by glycosyltransferases and salicylic acid." Journal of Hazardous Materials 283 (February 2015): 806–14. http://dx.doi.org/10.1016/j.jhazmat.2014.10.034.

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Olmez-Hanci, Tugba, Idil Arslan-Alaton, and Ozlem Gelegen. "Photo-Fenton-like treatment of K-acid: assessment of treatability, toxicity and oxidation products." Water Science and Technology 70, no. 6 (2014): 1056–64. http://dx.doi.org/10.2166/wst.2014.330.

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Photo-Fenton-like treatment of the commercially important naphthalene sulphonate K-acid (2-naphthylamine-3,6,8-trisulphonic acid) was investigated using UV-C, UV-A and visible light irradiation. Changes in toxicity patterns were followed by the Vibrio fischeri bioassay. Rapid and complete degradation of K-acid accompanied with nearly complete oxidation and mineralization rates (&gt;90%) were achieved for all studied irradiation types. On the other hand, detoxification was rather limited and did not change significantly during photo-Fenton-like treatment. Several oxidation products could be identified via liquid chromatograph–mass spectrometer analyses, such as desulphonated and hydroxylated naphthalene derivatives, quinones, and ring-opening as well as dimerization products. Photo-Fenton-like treatment of K-acid with UV-C, UV-A and visible light irradiation occurred through a series of hydroxylation and desulphonation reactions, followed by ring cleavage. A common degradation pathway for photo-Fenton-like treatment of K-acid using different irradiation types was proposed.

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SHUNXING, L., Z. FENGYING, C. WENLIAN, H. AIQIN, and X. YUKUN. "Surface modification of nanometer size TiO2 with salicylic acid for photocatalytic degradation of 4-nitrophenol." Journal of Hazardous Materials 135, no. 1-3 (2006): 431–36. http://dx.doi.org/10.1016/j.jhazmat.2005.12.010.

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Li, Yuejin, Xili Shang, Changhai Li, Xiaoming Huang, and Jingjing Zheng. "Novel p–n junction UiO-66/BiOI photocatalysts with efficient visible-light-induced photocatalytic activity." Water Science and Technology 77, no. 5 (2018): 1441–48. http://dx.doi.org/10.2166/wst.2018.026.

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Abstract Novel visible-light-induced UiO-66/BiOI photocatalysts with a p–n junction structure have been prepared for the first time through a facile hydrothermal method. The prepared photocatalysts were characterized using the powder X-ray diffraction, high resolution transmission electron microscopy, scanning electron microscopy, UV–visible diffuse reflectance spectra, and N2 adsorption–desorption (Brunauer–Emmett–Teller) techniques respectively. The photodegradation performances of UiO-66/BiOI photocatalysts were evaluated by photodegrading salicylic acid under visible-light irradiation. The UiO-66/BiOI composites displayed much higher photocatalytic efficiencies than pure BiOI under visible light. When the content of UiO-66 was 5.2 wt%, the composite (UiO-66/BiOI-2) has the best photocatalytic activity. Most of the salicylic acid molecules can be degraded in 100 min. The degradation rate of UiO-66/BiOI-2 samples is higher than single BiOI and UiO-66. The enhanced photocatalytic performance of UiO-66/BiOI may be ascribed to the formation of p–n heterojunctions between BiOI and UiO-66, which facilitates the transfer and separation of the photogenerated charge carriers. After recycling of the photocatalyst for five times for the photodegradation of salicylic acid, more than 85% of salicylic acid could still be degraded in the fifth cycle, implying that the as-prepared photocatalysts are highly stable.

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Ding, Mingmei, Wei Chen, Hang Xu та ін. "Novel α-Fe2O3/MXene nanocomposite as heterogeneous activator of peroxymonosulfate for the degradation of salicylic acid". Journal of Hazardous Materials 382 (січень 2020): 121064. http://dx.doi.org/10.1016/j.jhazmat.2019.121064.

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13

Vilhunen, S. H., and M. E. T. Sillanpää. "Atomic layer deposited (ALD) TiO2 and TiO2−x-Nx thin film photocatalysts in salicylic acid decomposition." Water Science and Technology 60, no. 10 (2009): 2471–75. http://dx.doi.org/10.2166/wst.2009.660.

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Degradation of salicylic acid (SA) with thin film photocatalyst, titanium dioxide (TiO2) and nitrogen-doped TiO2 (TiO2−x-Nx) combined with ultraviolet (UV) radiation was studied. TiO2 film with thickness of 15 and 65 nm was tested. The TiO2−x-Nx film had thickness of 15 nm on top of TiO2 (50 nm). Photocatalysts were prepared on glass substrate by atomic layer deposition (ALD) technique. The effect of initial pH (3–10) was studied with SA concentration of 10 mg/l. Decomposition of SA was fastest at pH 6 with both films and the rate was equal at initial pH values 3 and 4.3. However, at higher pH values the non-doped film was more efficient.

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Li, Xiaozhou, Danliu Peng, Yue Zhang, Duan Ju, and Chunfeng Guan. "Achromobacter sp. PHED2 enhances the phenanthrene degradation and stress tolerance in maize involving the participation of salicylic acid." Environmental Technology & Innovation 21 (February 2021): 101365. http://dx.doi.org/10.1016/j.eti.2021.101365.

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Bracco, Estefania, Matías Butler, Patricio Carnelli, and Roberto Candal. "TiO2 and N-TiO2-photocatalytic degradation of salicylic acid in water: characterization of transformation products by mass spectrometry." Environmental Science and Pollution Research 27, no. 23 (2019): 28469–79. http://dx.doi.org/10.1007/s11356-019-06045-6.

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Wang, Junhong, Xianzhao Shao, Junhai Liu, Xiaohui Ji, Jianqi Ma, and Guanghui Tian. "Fabrication of CdS-SBA-15 nanomaterials and their photocatalytic activity for degradation of salicylic acid under visible light." Ecotoxicology and Environmental Safety 190 (March 2020): 110139. http://dx.doi.org/10.1016/j.ecoenv.2019.110139.

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17

Schönerklee, M., M. Peev, H. De Wever, T. Reemtsma, and S. Weiss. "Modelling the degradation of micropollutants in wastewater: parameter estimation and application to pilot (laboratory-scale) MBR data in the case of 2,6-NDSA and BTSA." Water Science and Technology 59, no. 1 (2009): 149–57. http://dx.doi.org/10.2166/wst.2009.590.

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The paper summarises the definition of an extended biokinetic model dedicated to micropollutant degradation in wastewater treatment and the parameter estimation methodology for this model. Additionally it describes results on experimental parameter estimation for two target micropollutants, naphthalene disulfonate (2,6-NDSA) and benzothiazole sulfonic acid (BTSA). Subsequently the parameterised model is applied to real operational data from two laboratory-scale (MBR) installations. The work presents the full chain of theoretical model development, model analysis and practical application to case study data for micropollutants.

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Hijosa-Valsero, M., V. Matamoros, R. Sidrach-Cardona, et al. "Influence of design, physico-chemical and environmental parameters on pharmaceuticals and fragrances removal by constructed wetlands." Water Science and Technology 63, no. 11 (2011): 2527–34. http://dx.doi.org/10.2166/wst.2011.500.

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The ability of several mesocosm-scale and full-scale constructed wetlands (CWs) to remove pharmaceuticals and personal care products (PPCPs) from urban wastewater was assessed. The results of three previous works were considered as a whole to find common patterns in PPCP removal. The experiment took place outdoors under winter and summer conditions. The mesocosm-scale CWs differed in some design parameters, namely the presence of plants, the vegetal species chosen (Typha angustifolia versus Phragmites australis), the flow configuration (surface flow versus subsurface flow), the primary treatment (sedimentation tank versus HUSB), the feeding regime (batch flow versus continuous saturation) and the presence of gravel bed. The full-scale CWs consisted of a combination of various subsystems (ponds, surface flow CWs and subsurface flow CWs). The studied PPCPs were ketoprofen, naproxen, ibuprofen, diclofenac, salicylic acid, carbamazepine, caffeine, methyl dihydrojasmonate, galaxolide and tonalide. The performance of the evaluated treatment systems was compound dependent and varied as a function of the CW-configuration. In addition, PPCP removal efficiencies were lower during winter. The presence of plants favoured naproxen, ibuprofen, diclofenac, salicylic acid, caffeine, methyl dihydrojasmonate, galaxolide and tonalide removal. Significant positive correlations were observed between the removal of most PPCPs and temperature or redox potential. Accordingly, microbiological pathways appear to be the most likely degradation route for the target PPCPs in the CWs studied.

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Jing, Chang, Wang Shaopo, Zhang Yaxue, et al. "Oxidation of salicylic acid in water by the O3 and UV/O3 processes: removal and reaction byproducts." Water Science and Technology 81, no. 4 (2020): 753–62. http://dx.doi.org/10.2166/wst.2020.155.

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Abstract In this study, the removal of salicylic acid (SA) in water by ozone (O3) and ultraviolet/ozone (UV/O3) processes was investigated. Results showed that more than 50% of SA (10 mg/L) could be effectively removed after 1 min during these two processes. However, the UV/O3 process was much more effective than the O3 process for SA mineralization, and the total organic carbon reduction after 30 min was 69.5% and 28.1%, respectively. In the two processes, the optimum pH value for SA removal was 4.3, while that for SA mineralization was 10.0. Both bicarbonate and dissolved organic carbon significantly inhibited SA removal during the two processes. Eleven oxidation byproducts were detected in O3 process, but only four byproducts were observed in UV/O3 process. Three hydroxylation aromatic products were identified as the initial byproducts during SA degradation. Glyoxylic acid monohydrate, glycolic acid, and oxalic acid were accumulated in O3 process but not observed in UV/O3 process. Oxalic acid was the only detected small molecular byproduct in UV/O3 process, and it could be further mineralized, thereby indicating that UV/O3 had a greater potential for degrading both SA and its reaction byproducts.

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Cai, Shaokang, Shurong Zhang, Canzhu Gao, and Zhongfa Cheng. "Degradation of fluorescent dye-Solvent Green 7 (HPTS) in wastewater by advanced oxidation process." Water Science and Technology 82, no. 11 (2020): 2525–35. http://dx.doi.org/10.2166/wst.2020.534.

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Abstract Solvent Green 7 (HPTS) is a widely used fluorescent dye. As a kind of polycyclic aromatic hydrocarbon (PAHs) derivative, HPTS would cause pollution when it is discharged into the environment. This study adopted advanced oxidation processes (UV/H2O2) to degrade the HPTS in aqueous solution and investigated the effects of various factors on the degradation. The results showed that: the initial concentration and the fluorescence characteristics of HPTS reduced the degradation efficiency. When the oxidant concentration of H2O2 was 3 mg/L, the degradation efficiency and cost of HPTS (20 mg/L) were the most appropriate; when there were various inorganic anions in the solution, the degradations were not affected, but when the solution was strong acid and there existed a lot of chloride ions, the degradation of HPTS was inhibited. The degradation pathways indicated HPTS degraded into naphthalene derivatives, benzene derivatives through oxidation and decarboxylation reactions, finally into water and carbon dioxide. Further research for substances similar to HPTS structure will make progress in understanding the degradation process of PAHs.

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Zhuang, W. Q., J. H. Tay, A. M. Maszenan, and S. T. L. Tay. "Isolation of naphthalene-degrading bacteria from tropical marine sediments." Water Science and Technology 47, no. 1 (2003): 303–8. http://dx.doi.org/10.2166/wst.2003.0071.

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Oil pollution is a major environmental concern in many countries, and this has led to a concerted effort in studying the feasibility of using oil-degrading bacteria for bioremediation. Although many oil-degrading bacteria have been isolated from different environments, environmental conditions can impose a selection pressure on the types of bacteria that can reside in a particular environment. This study reports the successful isolation of two indigenous naphthalene-degrading bacteria from oil-contaminated tropical marine sediments by enrichment culture. Strains MN-005 and MN-006 were characterized using an extensive range of biochemical tests. The 16S ribosomal deoxyribonucleic acid (rDNA) sequence analysis was also performed for the two strains. Their naphthalene degradation capabilities were determined using gas chromatography and DAPI counting of bacterial cells. Strains MN-005 and MN-006 are phenotypically and phylogenetically different from each other, and belong to the genera Staphylococcus and Micrococcus, respectively. Strains MN-005 and MN-006 had maximal specific growth rates (μmax) of 0.082 ± 0.008 and 0.30 ± 0.02 per hour, respectively, and half-saturation constants (Ks) of 0.79 ± 0.10 and 2.52 ± 0.32 mg per litre, respectively. These physiological and growth studies are useful in assessing the potential of these indigenous isolates for in situ or ex situ naphthalene pollutant bioremediation in tropical marine environments.

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Zhou, Chengyun, Danlian Huang, Piao Xu, et al. "Efficient visible light driven degradation of sulfamethazine and tetracycline by salicylic acid modified polymeric carbon nitride via charge transfer." Chemical Engineering Journal 370 (August 2019): 1077–86. http://dx.doi.org/10.1016/j.cej.2019.03.279.

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Duan, Yongzheng, and Yulian Shen. "Synthesis of ZnO-CuO/MCM-48 photocatalyst for the degradation of organic pollutions." Water Science and Technology 76, no. 1 (2017): 172–81. http://dx.doi.org/10.2166/wst.2017.196.

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The photocatalytic properties of ZnO-CuO catalysts supported on siliceous MCM-48 (Mobil Composition of Matter No. 48) for the degradation of organic pollutions such as methylene blue and salicylic acid under UV light irradiation were investigated. These catalysts were prepared by impregnation of MCM-48 with a mixed aqueous solution of copper acetate and zinc acetate. X-ray diffraction, N2-physisorption, high resolution transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and photoluminescence were used to characterize these samples. Results from characterizations showed that the addition of ZnO to CuO/MCM-48 could markedly improve the photocatalytic degradation properties. The enhanced photocatalytic behaviors of ZnO-CuO/MCM-48 may be due to the formation of p-n heterojunctions between ZnO and CuO, resulting in the effective separation of photogenerated electron–hole pairs. Moreover, the photocatalysts were easily recovered and reused for five cycles without considerable loss of activity.

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Yue, P. L., J. Y. Feng, and X. Hu. "Photo-Fenton reaction using a nanocomposite." Water Science and Technology 49, no. 4 (2004): 85–90. http://dx.doi.org/10.2166/wst.2004.0228.

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A laponite RD clay-based Fe nanocomposite (Fe-Lap-RD) has been synthesized by the so-called pillaring technique. The X-ray diffraction (XRD) results reveal that the Fe-Lap-RD mainly consists of Fe2O3 (maghemite) crystallites and Fe2SiO10(OH)2 (iron silicate hydroxide) crystallites, respectively. The photo-catalytic activity of the Fe-Lap-RD for the degradation of an organic azo dye Orange II is examined. It is found that the rate of mineralization of Orange II is slower than that of discoloration. Under optimal conditions, 100% color and 70% total organic carbon (TOC) of 0.2 mM Orange II can be removed in 45 and 90 minutes, respectively. In addition, the performance of a strongly acidic type of ion exchange resin based catalyst as a heterogeneous photo-Fenton catalyst for the degradation of salicylic acid is also discussed.

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Chen, Hao, Yan Feng, Ning Suo, et al. "Preparation of particle electrodes from manganese slag and its degradation performance for salicylic acid in the three-dimensional electrode reactor (TDE)." Chemosphere 216 (February 2019): 281–88. http://dx.doi.org/10.1016/j.chemosphere.2018.10.097.

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Arslan, Evrim, Basak Savun Hekimoglu, Sesil Agopcan Cinar, Nilsun Ince, and Viktorya Aviyente. "Hydroxyl radical-mediated degradation of salicylic acid and methyl paraben: an experimental and computational approach to assess the reaction mechanisms." Environmental Science and Pollution Research 26, no. 32 (2019): 33125–34. http://dx.doi.org/10.1007/s11356-019-06048-3.

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Li, Yang, Yi Ren, and Nan Jiang. "Analysis of Draft Genome Sequence of Pseudomonas sp. QTF5 Reveals Its Benzoic Acid Degradation Ability and Heavy Metal Tolerance." BioMed Research International 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/4565960.

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Pseudomonas sp. QTF5 was isolated from the continuous permafrost near the bitumen layers in the Qiangtang basin of Qinghai-Tibetan Plateau in China (5,111 m above sea level). It is psychrotolerant and highly and widely tolerant to heavy metals and has the ability to metabolize benzoic acid and salicylic acid. To gain insight into the genetic basis for its adaptation, we performed whole genome sequencing and analyzed the resistant genes and metabolic pathways. Based on 120 published and annotated genomes representing 31 species in the genus Pseudomonas, in silico genomic DNA-DNA hybridization (<54%) and average nucleotide identity calculation (<94%) revealed that QTF5 is closest to Pseudomonas lini and should be classified into a novel species. This study provides the genetic basis to identify the genes linked to its specific mechanisms for adaptation to extreme environment and application of this microorganism in environmental conservation.

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Zhang, Liping, Shengnian Wu, Jun Xiang, Xiaofei Jiao, and Jing Wang. "Research on treatment and mechanism of salicylhydroxamic acid flotation wastewater by O3-BAF process." Water Science and Technology 82, no. 5 (2020): 861–76. http://dx.doi.org/10.2166/wst.2020.388.

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Abstract Salicylhydroxamic acid is an effective and selective collector for tungsten and molybdenum ores. However, the salicylhydroxamic acid flotation wastewater discharge may cause damage to the water environment for the residual processing reagents with poor biodegradability. Combined O3 and biological aerated filter (BAF) has a well-known potential for removing refractory or toxic organic pollutants. Combined process of O3 and BAF (O3-BAF) was applied to treat the simulated wastewater from W-Mo mineral processing in this study. Compared single ozonation to O3-BAF, various influencing factors were discussed like O3 dosage, reaction time, initial pH value, gas–water ratio and organic loading. Meanwhile, degradation mechanism of salicylhydroxamic acid was reduced. Under the optimal experiment conditions as pH value 8, O3 dosage 1.3 mg·L−1, reaction time 15 min, the five-day biochemical oxygen demand (BOD5)/chemical oxygen demand of potassium dichromate (CODCr) value increased to from 0.19 to 0.35. The effluent was pumped to the following BAF process, when the optimal experiment conditions was organic load = 0.82 kgCODCr (m−3·d−1), gas-water ratio = 6:1, CODCr concentration of effluent was 28.92 mg·L−1 and the removal ratio was 86.26%, while the removal ratio could higher to 91.12% for the O3-BAF combined process. The effluent could meet the discharge and reuse emission standards requirements in China. UV-vis absorption spectra and high performance liquid chromatography showed the degradation pathway of salicylhydroxamic acid by ozone oxidation was salicylhydroxamic acid → salicylic acid + hydroxylamine → catechol → maleic → small molecular organic acid → carbon dioxide + water.

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Seo, Jong-Su, Young-Soo Keum, Yuting Hu, Sung-Eun Lee, and Qing X. Li. "Phenanthrene degradation in Arthrobacter sp. P1-1: Initial 1,2-, 3,4- and 9,10-dioxygenation, and meta- and ortho-cleavages of naphthalene-1,2-diol after its formation from naphthalene-1,2-dicarboxylic acid and hydroxyl naphthoic acids." Chemosphere 65, no. 11 (2006): 2388–94. http://dx.doi.org/10.1016/j.chemosphere.2006.04.067.

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Wang, Yin, Yun Wang, Lan Yu, Jiayuan Wang, Baobao Du, and Xiaodong Zhang. "Enhanced catalytic activity of templated-double perovskite with 3D network structure for salicylic acid degradation under microwave irradiation: Insight into the catalytic mechanism." Chemical Engineering Journal 368 (July 2019): 115–28. http://dx.doi.org/10.1016/j.cej.2019.02.174.

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Maruyama, Takahiro, Masaharu Ishikura, Hironori Taki, et al. "Isolation and Characterization of o-Xylene Oxygenase Genes from Rhodococcus opacus TKN14." Applied and Environmental Microbiology 71, no. 12 (2005): 7705–15. http://dx.doi.org/10.1128/aem.71.12.7705-7715.2005.

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ABSTRACT o-Xylene is one of the most difficult-to-degrade environmental pollutants. We report here Rhodococcus genes mediating oxygenation in the first step of o-xylene degradation. Rhodococcus opacus TKN14, isolated from soil contaminated with o-xylene, was able to utilize o-xylene as the sole carbon source and to metabolize it to o-methylbenzoic acid. A cosmid library from the genome of this strain was constructed in Escherichia coli. A bioconversion analysis revealed that a cosmid clone incorporating a 15-kb NotI fragment had the ability to convert o-xylene into o-methylbenzyl alcohol. The sequence analysis of this 15-kb region indicated the presence of a gene cluster significantly homologous to the naphthalene-inducible dioxygenase gene clusters (nidABCD) that had been isolated from Rhodococcus sp. strain I24. Complementation studies, using E. coli expressing various combinations of individual open reading frames, revealed that a gene (named nidE) for rubredoxin (Rd) and a novel gene (named nidF) encoding an auxiliary protein, which had no overall homology with any other proteins, were indispensable for the methyl oxidation reaction of o-xylene, in addition to the dioxygenase iron-sulfur protein genes (nidAB). Regardless of the presence of NidF, the enzyme composed of NidABE was found to function as a typical naphthalene dioxygenase for converting naphthalene and various (di)methylnaphthalenes into their corresponding cis-dihydrodiols. All the nidABEF genes were transcriptionally induced in R. opacus TKN14 by the addition of o-xylene to a mineral salt medium. It is very likely that these genes are involved in the degradation pathways of a wide range of aromatic hydrocarbons by Rhodococcus species as the first key enzyme.

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Lu, Feng Fan, Jin Tong Liu, Nan Zhang, Zhao Jie Chen, and Hong Yang. "OsPAL as a key salicylic acid synthetic component is a critical factor involved in mediation of isoproturon degradation in a paddy crop." Journal of Cleaner Production 262 (July 2020): 121476. http://dx.doi.org/10.1016/j.jclepro.2020.121476.

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Vila, Joaquim, Zaira López, Jordi Sabaté, Cristina Minguillón, Anna M. Solanas, and Magdalena Grifoll. "Identification of a Novel Metabolite in the Degradation of Pyrene by Mycobacterium sp. Strain AP1: Actions of the Isolate on Two- and Three-Ring Polycyclic Aromatic Hydrocarbons." Applied and Environmental Microbiology 67, no. 12 (2001): 5497–505. http://dx.doi.org/10.1128/aem.67.12.5497-5505.2001.

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ABSTRACT Mycobacterium sp. strain AP1 grew with pyrene as a sole source of carbon and energy. The identification of metabolites accumulating during growth suggests that this strain initiates its attack on pyrene by either monooxygenation or dioxygenation at its C-4, C-5 positions to give trans- orcis-4,5-dihydroxy-4,5-dihydropyrene, respectively. Dehydrogenation of the latter, ortho cleavage of the resulting diol to form phenanthrene 4,5-dicarboxylic acid, and subsequent decarboxylation to phenanthrene 4-carboxylic acid lead to degradation of the phenanthrene 4-carboxylic acid via phthalate. A novel metabolite identified as 6,6′-dihydroxy-2,2′-biphenyl dicarboxylic acid demonstrates a new branch in the pathway that involves the cleavage of both central rings of pyrene. In addition to pyrene, strain AP1 utilized hexadecane, phenanthrene, and fluoranthene for growth. Pyrene-grown cells oxidized the methylenic groups of fluorene and acenaphthene and catalyzed the dihydroxylation andortho cleavage of one of the rings of naphthalene and phenanthrene to give 2-carboxycinnamic and diphenic acids, respectively. The catabolic versatility of strain AP1 and its use ofortho cleavage mechanisms during the degradation of polycyclic aromatic hydrocarbons (PAHs) give new insight into the role that pyrene-degrading bacterial strains may play in the environmental fate of PAH mixtures.

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Duguet, J. P., B. Dussert, J. Mallevialle, and F. Fiessinger. "Polymerization Effects of Ozone: Applications to the Removal of Phenolic Compounds from Industrial Wastewaters." Water Science and Technology 19, no. 5-6 (1987): 919–30. http://dx.doi.org/10.2166/wst.1987.0270.

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Degradation of phenols by ozone has been extensively studied but the oxidative coupling pathway of ozone resulting in a phenol polymerization has not been largely investigated. Application of low ozone dose in solutions of 2.4 dichlorophenol and salicylic acid is characterized by the formation of high molecular compounds which are partially insoluble. Numerous polymers have been identified by gas chromatography coupled with mass spectrometry. Application of the polymerization effect of ozone to petrochemical and coking wastewaters containing phenols give similar results. In each case, phenolic compounds are efficiently removed, even if a large organic content is present. In the case of petrochemical wastewater, where phenols represent only 30% of TOC, the ozone effects are not sufficient to merit an ozonation step on the present treatment line. On the other hand, when phenols represent the greater part of the organics, as in coking wastewater, an important fraction of insoluble compounds, easily removed by filtration, are formed.

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Schink, B. "Anaerobic digestion: concepts, limits and perspectives." Water Science and Technology 45, no. 10 (2002): 1–8. http://dx.doi.org/10.2166/wst.2002.0274.

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Anaerobic degradation processes are faced with limitations with respect to reaction energetics and reaction kinetics. The small amount of energy available in methanogenic degradation of complex organic compounds allows in most cases only the conservation of minimum amounts of energy in the lowest range of energy exploitable by biochemical reactions for ATP-synthesis. This limit has to be defined in the range of 1/3–1/4 of an ATP unit, or 15–20 kJ per mol reaction. Such small amounts of energy are exploited efficiently by syntrophic microbial communities co-operating e.g. in fatty acid conversion to methane and CO2. Methanogens also set the stage for efficient conversion of sugars or amino acids, and channel electron fluxes to the utmost efficiency. Kinetic limitations are set by the inertness of certain compounds, e.g. hydrocarbons, to react in the absence of a strong oxidant. New reactions have been found recently which activate such compounds, e.g. aromatic hydrocarbons such as toluene, xylenes, naphthalene, methane, or ammonia. Refined techniques for analysis of microbial activities in ill defined natural environments such as digestive tracts of small invertebrates or polluted aquifers have shown an amazing capacity for anaerobic or oxygen-limited degradation processes that are still to be exploited. Thus, anaerobic digestion is still a matter of fast increasing knowledge, both on the side of basic research as well as on the side of application in treatment of soil, waste materials, or in understanding complex living communities.

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Godin, Simon, Pawel Kubica, Anthony Ranchou-Peyruse, et al. "An LC-MS/MS Method for a Comprehensive Determination of Metabolites of BTEX Anaerobic Degradation in Bacterial Cultures and Groundwater." Water 12, no. 7 (2020): 1869. http://dx.doi.org/10.3390/w12071869.

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BTEX (benzene, toluene, ethylbenzene, and the different xylene isomers), known for carcinogenic and neurotoxic effects, are common environmental contaminants. The first step for the development of the bioremediation technologies is the detection of intense microbial degradation in contaminated waters in the quest for the most active bacterial strains. This requires the multispecies analysis for BTEX metabolites which are considered as markers of microbial degradation. A direct (50 µL injection) HPLC–electrospray MS/MS analytical method was developed for the simultaneous analysis of 11 BTEX metabolites (o-, m-, p-toluic, salicylic, benzoate, benzyl, and phenyl succinic acids, 2-(1-phenylethyl)-, 2-(2-methylbenzyl), and 2-(3-methylbenzyl)-, 2-(4-methyl benzyl)-succinic acids) in bacterial cultures and ground waters down to 0.1 ng/mL. The optimization of the chromatographic conditions allowed for the resolution of position isomers of toluic and methylbenzyl-succinic acids. The stability of the analytes during sample storage tested in different conditions showed the instability of some of them when stored at room temperature. The feasibility of the method was demonstrated by the detection of all the investigated metabolites in a water sample of a deep aquifer hosting natural gas storage. A model laboratory study emphasized the importance of 2-(2-methylbenzyl)-succinic acid as a marker of anaerobic microbial degradation.

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Todeschini, Vítor, Maximiliano da Silva Sangoi, Alianise da Silva Meira, Diogo Miron, Alini Dall Cortivo Lange, and Nadia Maria Volpato. "Stability-Indicating Micellar Electrokinetic Chromatography Technique for Simultaneous Measurement of Delapril and Manidipine from a Combination Drug Formulation." Journal of AOAC INTERNATIONAL 97, no. 1 (2014): 114–20. http://dx.doi.org/10.5740/jaoacint.10-337.

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Abstract A stability-indicating micellar electrokineticchromatography (MEKC) method was developed and validated for simultaneous analysis of delapril (DEL) and manidipine (MAN) using salicylic acid as an internal standard. The MEKC method was performed using a fused-silica capillary (effective length of 72 cm) with 50 mM of borate buffer and 5 mM of anionic surfactant sodium dodecylsulfate at pH9.0 as the background electrolyte. The separationwas achieved at 25 kV applied voltage and 35°C. The injection was performed at 50 mbar for5s, with detection at 208 nm. The method was linear in the range of 15–150 μg/mL (r2 = 0.9966) for DEL and 5–50 μg/mL (r2 = 0.9985) for MAN with adequate results for the precision (≤1.87%) and accuracy (98.94% for DEL and 100.65% for MAN). The specificity of the method and its stability-indicating capability was demonstrated through forced degradation studies, which showed that there was no interference from the excipients. The Plackett-Burman experimental design was used for robustness evaluation, giving results within the acceptable range. The method was successfully applied for analysis of the drugs, and the results were compared to an LC method, resulting in nonsignificant differences (P = 0.78 and0.84 for DEL and MAN, respectively).

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Apostolaki, Maria-Athina, Alexia Toumazatou, Maria Antoniadou, et al. "Graphene Quantum Dot-TiO2 Photonic Crystal Films for Photocatalytic Applications." Nanomaterials 10, no. 12 (2020): 2566. http://dx.doi.org/10.3390/nano10122566.

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Photonic crystal structuring has emerged as an advanced method to enhance solar light harvesting by metal oxide photocatalysts along with rational compositional modifications of the materials’ properties. In this work, surface functionalization of TiO2 photonic crystals by blue luminescent graphene quantum dots (GQDs), n–π* band at ca. 350 nm, is demonstrated as a facile, environmental benign method to promote photocatalytic activity by the combination of slow photon-assisted light trapping with GQD-TiO2 interfacial electron transfer. TiO2 inverse opal films fabricated by the co-assembly of polymer colloidal spheres with a hydrolyzed titania precursor were post-modified by impregnation in aqueous GQDs suspension without any structural distortion. Photonic band gap engineering by varying the inverse opal macropore size resulted in selective performance enhancement for both salicylic acid photocatalytic degradation and photocurrent generation under UV–VIS and visible light, when red-edge slow photons overlapped with the composite’s absorption edge, whereas stop band reflection was attenuated by the strong UVA absorbance of the GQD-TiO2 photonic films. Photoelectrochemical and photoluminescence measurements indicated that the observed improvement, which surpassed similarly modified benchmark mesoporous P25 TiO2 films, was further assisted by GQDs electron acceptor action and visible light activation to a lesser extent, leading to highly efficient photocatalytic films.

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Lopez-Echartea, Eglantina, Jachym Suman, Tereza Smrhova, et al. "Genomic analysis of dibenzofuran-degrading Pseudomonas veronii strain Pvy reveals its biodegradative versatility." G3 Genes|Genomes|Genetics 11, no. 2 (2020). http://dx.doi.org/10.1093/g3journal/jkaa030.

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Abstract Certain industrial chemicals accumulate in the environment due to their recalcitrant properties. Bioremediation uses the capability of some environmental bacteria to break down these chemicals and attenuate the pollution. One such bacterial strain, designated Pvy, was isolated from sediment samples from a lagoon in Romania located near an oil refinery due to its capacity to degrade dibenzofuran (DF). The genome sequence of the Pvy strain was obtained using an Oxford Nanopore MiniION platform. According to the consensus 16S rRNA gene sequence that was compiled from six 16S rRNA gene copies contained in the genome and orthologous average nucleotide identity (OrthoANI) calculation, the Pvy strain was identified as Pseudomonas veronii, which confirmed the identification obtained with the aid of MALDI-TOF mass spectrometry and MALDI BioTyper. The genome was analyzed with respect to enzymes responsible for the overall biodegradative versatility of the strain. The Pvy strain was able to derive carbon from naphthalene (NP) and several aromatic compounds of natural origin, including salicylic, protocatechuic, p-hydroxybenzoic, trans-cinnamic, vanillic, and indoleacetic acids or vanillin, and was shown to degrade but not utilize DF. In total seven loci were found in the Pvy genome, which enables the strain to participate in the degradation of these aromatic compounds. Our experimental data also indicate that the transcription of the NP-dioxygenase α-subunit gene (ndoB), carried by the plasmid of the Pvy strain, is inducible by DF. These features make the Pvy strain a potential candidate for various bioremediation applications.

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Elmasry, Manal S., Ahmed Serag, Wafaa S. Hassan, Magda Y. El-Mammli, and Mohamed Badrawy. "Spectrophotometric Determination of Aspirin and Omeprazole in the presence of Salicylic Acid as a Degradation Product: A Comparative Evaluation of Different Univariate/Multivariate Post Processing Algorithms." Journal of AOAC INTERNATIONAL, August 13, 2021. http://dx.doi.org/10.1093/jaoacint/qsab105.

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Abstract Background A recent combination of aspirin (ASP) and omeprazole (OMP) has been presented in a fixed dosage form for treatment of many CVD, particularly in patients with gastric diseases. However, ASP is very sensitive to degradation into salicylic acid (SAL) as its main degradation product. Hence, it is very important to develop methods for the determination of ASP and OMP in the presence of SAL. Objective In this study, UV spectrophotometry assisted by different univariate/multivariate post processing algorithms have been presented for quantitative determination of ASP, OMP and SAL without any prior separation. Methods The univariate/multivariate algorithms include double divisor ratio difference and double divisor mean centering as the univariate approaches while the multivariate methods include principal component regression (PCR) and partial least squares (PLS) models. Validation of the univariate methods was done according to the ICH guidelines while the multivariate models were validated using external validation set. Results The univariate algorithms displayed excellent regression and validation capabilities in terms of linearity, accuracy, precision, and selectivity. Regarding PCR and PLS, the number of latent variables were carefully optimized, and the model’s validation criteria displayed excellent recoveries and lower errors of prediction. Conclusion Our findings indicate that the developed methods were comparable to the only reported chromatographic methods but with much shorter analysis time and simplicity. Highlights Overall, this report presents the first spectrophotometric methods applied for determination of possible combination of ASP, OMP, and SAL, and poses theses methods as valuable analytical tools in in-process testing and quality control analysis.

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Journal articles on the topic 'Naphthalene Salicylic acid Environmental degradation'

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