Photo-fenton degradation of pentachlorophenol l: competition between additives and photolysis

[EN] In the present work, the photo-Fenton degradation of pentachlorophenol (PCP, 1 mg/L) has been studied under simulated and natural solar irradiation; moreover, the effect on the process efficiency of urban waste-derived soluble bio-based substances (SBO), structurally comparable to humic acids, has been investigated. Experiments showed a crucial role of PCP photolysis, present in the solar pilot plant and hindered by the Pyrex (R) filter present in the solar simulator. Indeed, the SBO screen negatively affects PCP degradation when working under natural solar light, where the photolysis of PCP is relevant. In contrast, in the absence of PCP photolysis, a significant improvement of the photo-Fenton process was observed when added to SBO. Furthermore, SBO were able to extend the application of the photo-Fenton process at circumneutral pH values, due to their ability to complex iron, avoiding its precipitation as oxides or hydroxides. This positive effect has been observed at higher concentration of Fe(II) (4 mg/L), whereas at 1 mg/L, the degradation rates of PCP were comparable in the presence and absence of SBO.This work was realized with the financial support of the academic interchange from the Marie Sklodowska-Curie Research and Innovation Staff Exchange project, funded by the European Commission H2020-MSCA-RISE-2014 within the framework of the research project Mat4treaT (Project number: 645551).Vergura, EP.; García-Ballesteros, S.; Vercher Pérez, RF.; Santos-Juanes Jordá, L.; Bianco Prevot, A.; Arqués Sanz, A. (2019). Photo-Fenton Degradation of Pentachlorophenol: Competition between Additives and Photolysis. Nanomaterials. 9(8):1-8. https://doi.org/10.3390/nano9081157S189

Quantitative determination of active Bowman-Birk isoinhibitors, IBB1 and IBBD2, in commercial soymilks

Naturally-occurring serine protease inhibitors of the Bowman-Birk family exert their potential chemopreventive and/or therapeutic properties via protease inhibition. In this study, we have quantified the amounts of active BBI isoinhibitors, IBB1 and IBBD2, in six commercial soymilks. By using cation exchange chromatography, the BBI isoinhibitors were isolated and their specific trypsin inhibitory activity was used to estimate their amounts in soymilk samples. IBB1 and IBBD2 concentrations ranged from 0.44 to 5.20 and 0.27 to 4.60 mg/100 ml of soymilk, respectively; total BBI, considered as the sum of both isoinhibitors, ranged from 0.60 to 9.07 mg/100 ml of soymilk. These data show that physiologically relevant amounts of active BBI are present in commercial soymilk and may exert potential health-promoting effects.A.C. acknowledges support by ERDF-co-financed Grant from the Spanish CICYT (AGL2011-26353). A.C. is involved in COST Action FA1005 INFOGEST on Food Digestion. L.C.B.R. acknowledges support from CAPES (Programa Institucional de Doutorado Sanduíche no Exterior–PDSE process number 9004-11-4), Brazil. We are grateful to the proteomics Facility of University of Cordoba (Spain) for carrying out peptide mass fingerprinting. B.H.-L. thanks Ministry of Economy and Competitiveness for her “Ramón y Cajal” contract.Peer Reviewe

Humic-like substances from urban waste as auxiliaries for photo-Fenton treatment: a fluorescence EEM-PARAFAC study

[EN] In this work, analysis of excitation-emission-matrices (EEM) has been employed to gain further insight into the characterization of humic like substances (HLS) obtained from urban wastes (soluble bio-organic substances, SBOs). In particular, complexation of these substances with iron and changes along a photo-Fenton process have been studied. Recorded EEMs were decomposed by using parallel factor analysis (PARAFAC). Three fluorescent components were identified by PARAFAC modeling of the entire set of SBO solutions studied. The EEM peak locations (lambda(ex)/lambda(em)) of these components were 310-330 nm/400-420 nm (C1), 340-360 nm/450-500 nm (C2), and 285 nm/335-380 nm (C3). Slight variations of the maximum position of each component with the solution pH were observed. The interaction of SBO with Fe(III) was characterized by determining the stability constants of the components with Fe(III) at different pH values, which were in the order of magnitude of the ones reported for humic substances and reached their highest values at pH = 5. Photochemical experiments employing SBO and Fe(III), with and without H2O2, showed pH-dependent trends for the evolution of the modeled components, which exhibited a strong correlation with the efficiency reported for the photo-Fenton processes in the presence of SBO at different pH values.This work was supported by Generalitat Valenciana, Conselleria d'Ecuacio, Cultura i esport, Spain (GV/2015/074), Spanish Ministerio de Economia y Competitividad (CTQ2015-69832-C4-4-R) and by the Marie Sklodowska-Curie Research and Innovation Staff Exchange project funded by the European Commission H2020-MSCA-RISE-2014 (Project number: 645551). F. S. G. E. and L. C. are researchers from CONICET, Argentina.García-Ballesteros, S.; Constante, M.; Vicente Candela, R.; Mora Carbonell, M.; Amat Payá, AM.; Arques Sanz, A.; Carlos, L.... (2017). Humic-like substances from urban waste as auxiliaries for photo-Fenton treatment: a fluorescence EEM-PARAFAC study. Photochemical & Photobiological Sciences. 16:38-45. https://doi.org/10.1039/c6pp00236fS384516Malato, S., Fernández-Ibáñez, P., Maldonado, M. I., Blanco, J., & Gernjak, W. (2009). Decontamination and disinfection of water by solar photocatalysis: Recent overview and trends. Catalysis Today, 147(1), 1-59. doi:10.1016/j.cattod.2009.06.018WANG, J. L., & XU, L. J. (2012). Advanced Oxidation Processes for Wastewater Treatment: Formation of Hydroxyl Radical and Application. Critical Reviews in Environmental Science and Technology, 42(3), 251-325. doi:10.1080/10643389.2010.507698Pignatello, J. J., Oliveros, E., & MacKay, A. (2006). Advanced Oxidation Processes for Organic Contaminant Destruction Based on the Fenton Reaction and Related Chemistry. Critical Reviews in Environmental Science and Technology, 36(1), 1-84. doi:10.1080/10643380500326564Papoutsakis, S., Miralles-Cuevas, S., Oller, I., Garcia Sanchez, J. L., Pulgarin, C., & Malato, S. (2015). Microcontaminant degradation in municipal wastewater treatment plant secondary effluent by EDDS assisted photo-Fenton at near-neutral pH: An experimental design approach. Catalysis Today, 252, 61-69. doi:10.1016/j.cattod.2015.02.005Klamerth, N., Malato, S., Agüera, A., & Fernández-Alba, A. (2013). Photo-Fenton and modified photo-Fenton at neutral pH for the treatment of emerging contaminants in wastewater treatment plant effluents: A comparison. Water Research, 47(2), 833-840. doi:10.1016/j.watres.2012.11.008De Luca, A., Dantas, R. F., & Esplugas, S. (2015). Study of Fe(III)-NTA chelates stability for applicability in photo-Fenton at neutral pH. Applied Catalysis B: Environmental, 179, 372-379. doi:10.1016/j.apcatb.2015.05.025Bernabeu, A., Palacios, S., Vicente, R., Vercher, R. F., Malato, S., Arques, A., & Amat, A. M. (2012). Solar photo-Fenton at mild conditions to treat a mixture of six emerging pollutants. Chemical Engineering Journal, 198-199, 65-72. doi:10.1016/j.cej.2012.05.056Klamerth, N., Malato, S., Maldonado, M. I., Agüera, A., & Fernández-Alba, A. (2011). Modified photo-Fenton for degradation of emerging contaminants in municipal wastewater effluents. Catalysis Today, 161(1), 241-246. doi:10.1016/j.cattod.2010.10.074Voelker, B. M., Morel, F. M. M., & Sulzberger, B. (1997). Iron Redox Cycling in Surface Waters:  Effects of Humic Substances and Light. Environmental Science & Technology, 31(4), 1004-1011. doi:10.1021/es9604018De la Cruz, N., Giménez, J., Esplugas, S., Grandjean, D., de Alencastro, L. F., & Pulgarín, C. (2012). Degradation of 32 emergent contaminants by UV and neutral photo-fenton in domestic wastewater effluent previously treated by activated sludge. Water Research, 46(6), 1947-1957. doi:10.1016/j.watres.2012.01.014Gomis, J., Vercher, R. F., Amat, A. M., Mártire, D. O., González, M. C., Bianco Prevot, A., … Carlos, L. (2013). Application of soluble bio-organic substances (SBO) as photocatalysts for wastewater treatment: Sensitizing effect and photo-Fenton-like process. Catalysis Today, 209, 176-180. doi:10.1016/j.cattod.2012.08.036Gomis, J., Carlos, L., Prevot, A. B., Teixeira, A. C. S. C., Mora, M., Amat, A. M., … Arques, A. (2015). Bio-based substances from urban waste as auxiliaries for solar photo-Fenton treatment under mild conditions: Optimization of operational variables. Catalysis Today, 240, 39-45. doi:10.1016/j.cattod.2014.03.034Gomis, J., Bianco Prevot, A., Montoneri, E., González, M. C., Amat, A. M., Mártire, D. O., … Carlos, L. (2014). Waste sourced bio-based substances for solar-driven wastewater remediation: Photodegradation of emerging pollutants. Chemical Engineering Journal, 235, 236-243. doi:10.1016/j.cej.2013.09.009Avetta, P., Berto, S., Bianco Prevot, A., Minella, M., Montoneri, E., Persico, D., … Arques, A. (2015). Photoinduced transformation of waste-derived soluble bio-based substances. Chemical Engineering Journal, 274, 247-255. doi:10.1016/j.cej.2015.03.126Gomis, J., Gonçalves, M. G., Vercher, R. F., Sabater, C., Castillo, M.-A., Prevot, A. B., … Arques, A. (2015). Determination of photostability, biocompatibility and efficiency as photo-Fenton auxiliaries of three different types of soluble bio-based substances (SBO). Catalysis Today, 252, 177-183. doi:10.1016/j.cattod.2014.10.015Berkovic, A. M., García Einschlag, F. S., Gonzalez, M. C., Pis Diez, R., & Mártire, D. O. (2013). Evaluation of the Hg2+binding potential of fulvic acids from fluorescence excitation–emission matrices. Photochem. Photobiol. Sci., 12(2), 384-392. doi:10.1039/c2pp25280eStedmon, C. A., & Bro, R. (2008). Characterizing dissolved organic matter fluorescence with parallel factor analysis: a tutorial. Limnology and Oceanography: Methods, 6(11), 572-579. doi:10.4319/lom.2008.6.572Ishii, S. K. L., & Boyer, T. H. (2012). Behavior of Reoccurring PARAFAC Components in Fluorescent Dissolved Organic Matter in Natural and Engineered Systems: A Critical Review. Environmental Science & Technology, 46(4), 2006-2017. doi:10.1021/es2043504Su, Y., Chen, F., & Liu, Z. (2015). Comparison of optical properties of chromophoric dissolved organic matter (CDOM) in alpine lakes above or below the tree line: insights into sources of CDOM. Photochemical & Photobiological Sciences, 14(5), 1047-1062. doi:10.1039/c4pp00478gYang, X., Meng, F., Huang, G., Sun, L., & Lin, Z. (2014). Sunlight-induced changes in chromophores and fluorophores of wastewater-derived organic matter in receiving waters – The role of salinity. Water Research, 62, 281-292. doi:10.1016/j.watres.2014.05.050Wu, J., Zhang, H., He, P.-J., & Shao, L.-M. (2011). Insight into the heavy metal binding potential of dissolved organic matter in MSW leachate using EEM quenching combined with PARAFAC analysis. Water Research, 45(4), 1711-1719. doi:10.1016/j.watres.2010.11.022Yamashita, Y., & Jaffé, R. (2008). Characterizing the Interactions between Trace Metals and Dissolved Organic Matter Using Excitation−Emission Matrix and Parallel Factor Analysis. Environmental Science & Technology, 42(19), 7374-7379. doi:10.1021/es801357hNisticò, R., Barrasso, M., Carrillo Le Roux, G. A., Seckler, M. M., Sousa, W., Malandrino, M., & Magnacca, G. (2015). Biopolymers from Composted Biowaste as Stabilizers for the Synthesis of Spherical and Homogeneously Sized Silver Nanoparticles for Textile Applications on Natural Fibers. ChemPhysChem, 16(18), 3902-3909. doi:10.1002/cphc.201500721Ohno, T. (2002). Fluorescence Inner-Filtering Correction for Determining the Humification Index of Dissolved Organic Matter. Environmental Science & Technology, 36(4), 742-746. doi:10.1021/es0155276Bahram, M., Bro, R., Stedmon, C., & Afkhami, A. (2006). Handling of Rayleigh and Raman scatter for PARAFAC modeling of fluorescence data using interpolation. Journal of Chemometrics, 20(3-4), 99-105. doi:10.1002/cem.978Ryan, D. K., & Weber, J. H. (1982). Fluorescence quenching titration for determination of complexing capacities and stability constants of fulvic acid. Analytical Chemistry, 54(6), 986-990. doi:10.1021/ac00243a033Yan, M., Fu, Q., Li, D., Gao, G., & Wang, D. (2013). Study of the pH influence on the optical properties of dissolved organic matter using fluorescence excitation–emission matrix and parallel factor analysis. Journal of Luminescence, 142, 103-109. doi:10.1016/j.jlumin.2013.02.052Dryer, D. J., Korshin, G. V., & Fabbricino, M. (2008). In Situ Examination of the Protonation Behavior of Fulvic Acids Using Differential Absorbance Spectroscopy. Environmental Science & Technology, 42(17), 6644-6649. doi:10.1021/es800741uGhosh, K., & Schnitzer, M. (1981). Fluorescence Excitation Spectra and Viscosity Behavior of a Fulvic Acid and its Copper and Iron Complexes1. Soil Science Society of America Journal, 45(1), 25. doi:10.2136/sssaj1981.03615995004500010005xLyon, B. A., Cory, R. M., & Weinberg, H. S. (2014). Changes in dissolved organic matter fluorescence and disinfection byproduct formation from UV and subsequent chlorination/chloramination. Journal of Hazardous Materials, 264, 411-419. doi:10.1016/j.jhazmat.2013.10.065Poulin, B. A., Ryan, J. N., & Aiken, G. R. (2014). Effects of Iron on Optical Properties of Dissolved Organic Matter. Environmental Science & Technology, 48(17), 10098-10106. doi:10.1021/es502670rXu, H., Yan, Z., Cai, H., Yu, G., Yang, L., & Jiang, H. (2013). Heterogeneity in metal binding by individual fluorescent components in a eutrophic algae-rich lake. Ecotoxicology and Environmental Safety, 98, 266-272. doi:10.1016/j.ecoenv.2013.09.008Esteves da Silva, J. (1998). Fluorescence quenching of anthropogenic fulvic acids by Cu(II), Fe(III) and UO22+. Talanta, 45(6), 1155-1165. doi:10.1016/s0039-9140(97)00224-5Zhao, J., & Nelson, D. J. (2005). Fluorescence study of the interaction of Suwannee River fulvic acid with metal ions and Al3+-metal ion competition. Journal of Inorganic Biochemistry, 99(2), 383-396. doi:10.1016/j.jinorgbio.2004.10.005Mikutta, C., & Kretzschmar, R. (2011). Spectroscopic Evidence for Ternary Complex Formation between Arsenate and Ferric Iron Complexes of Humic Substances. Environmental Science & Technology, 45(22), 9550-9557. doi:10.1021/es202300wOrsetti, S., Laskov, C., & Haderlein, S. B. (2013). Electron Transfer between Iron Minerals and Quinones: Estimating the Reduction Potential of the Fe(II)-Goethite Surface from AQDS Speciation. Environmental Science & Technology, 47(24), 14161-14168. doi:10.1021/es403658gLopes, L., de Laat, J., & Legube, B. (2002). Charge Transfer of Iron(III) Monomeric and Oligomeric Aqua Hydroxo Complexes:  Semiempirical Investigation into Photoactivity. Inorganic Chemistry, 41(9), 2505-2517. doi:10.1021/ic011029

Combining ZVI reduction with photo-Fenton process for the removal of persistent pollutants

An iron-based photochemical process able to act via reductive and oxidative stages by tuning experimental conditions has been explored. In a first step, zero-valent iron (ZVI), added as steel wool, was used to reduce those pollutants reluctant to oxidative processes. Then, the iron released in the solution was employed, upon addition of hydrogen peroxide, to drive a photo-Fenton process. This procedure has been checked with a mixture of five chemicals, namely p-toluenesulfonic acid, benzoic acid, p-nitrobenzoic acid, acetaminophen and caffeic. p-Nitrobenzoic acid resulted to be the most reluctant against oxidation but it was reduced in the absence of H2O2 to form 4-aminobenzoic acid; the presence of salts (e.g. tap water) was required and best results were reached at neutral pH. As p-aminobenzoic acid can be more easily oxidized than p-nitrobenzoic, combination of both stages is meaningful: a ZVI-based reduction followed by a photo-Fenton like-oxidation was employed to remove this pollutant from tested solutions.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Internalization of the anti-carcinogenic IBB1, a major Bowman-Birk isoinhibitor from soybean (Glycine max), in HT29 colon cancer cells

Proceedings of the I Congress PIIISA celebrado en la Estación Experimental del Zaidín (Granada), en mayo de 2013.Protease inhibitors of the Bowman-Birk type, a major protease inhibitor family in legume seeds, which inhibit potently trypsin- and chymotrypsin-like proteases, are currently being investigated as colorectal chemopreventive agents. Although the therapeutic target/s and the action mechanism/s of Bowman-Birk inhibitors (BBI) have not yet been elucidated, the emerging evidence suggests that BBI exert their chemopreventive properties via protease inhibition; in this sense, serine proteases should be considered as primary targets in early stages of carcinogenesis. In this work, we have demonstrated that IBB1, a major protease inhibitor of the Bowman-Birk family in soybean (Glycine max), exerts anti-proliferative effect in human colorectal HT29 cancer cells at concentrations higher than 15 μM, in a dose dependent manner. By using confocal microscopy, we have demonstrated that IBB1 is taken up by HT29 colon cancer cells in a time-dependent manner, being the bulk of the internalized protease inhibitor localized in the cytoplasm where might interact with their potential therapeutic target/s.This work was supported by ERDF-co-financed grants AGL2011-26353 (Spanish Ministry of Economy and Competitiveness) and PE2010-CVI-5767 (Junta de Andalucía).Peer reviewe

Reaction kinetics and mechanisms of organosilicon fungicide flusilazole with sulfate and hydroxyl radicals

Flusilazole is an organosilane fungicide used for treatments in agriculture and horticulture for control of diseases. The reaction kinetics and mechanism of flusilazole with sulfate and hydroxyl radicals were studied. The rate constant of the radicals with the fungicide were determined by laser flash photolysis of peroxodisulfate and hydrogen peroxide. The results were 2.0 × 109 s-1M-1 for the reaction of the fungicide with HO· and 4.6 × 108 s-1 M-1 for the same reaction with SO4·⁻ radicals. The absorption spectra of organic intermediates detected by laser flash photolysis of S2O2/8⁻ with flusilazole, were identified as α-aminoalkyl and siloxyl radicals and agree very well with those estimated employing the time-dependent density functional theory with explicit account for bulk solvent effects. In the continuous photolysis experiments, performed by photo-Fenton reaction of the fungicide, the main degradation products were: (bis(4-fluorophenyl)-hydroxy-methylsilane) and the non-toxic silicic acid, diethyl bis(trimethylsilyl) ester, in ten and twenty minutes of reaction, respectively.Facultad de Ciencias ExactasInstituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Application of soluble bio-organic substances (SBO) as photocatalysts for wastewater treatment: Sensitizing effect and photo-Fenton-like process

Soluble bio-organic substances (SBO) isolated from urban biorefuses have been investigated in photocatalytic processes for wastewater treatment using a cationic dye, namely crystal violet (CV) as target compound. The SBO have been found to enhance the photobleaching of CV solutions with an optimal SBO concentration of ca. 20 mg L-1. Mechanistic investigation based on chemical probes and changes in the absorption spectrum of CV in the presence of SBO seems to indicate that a complex formed between sensitizer and substrate plays a major role in the process. SBO have also been tested for the implementation of photo-Fenton processes at circumneutral media: the observed pseudo first order rate constants for CV decoloration was higher for UV/SBO/Fe(II)/H2O2 (5.5 x 10(-3) min(-1)) than for UV/Fe(II)/H2O2 (1.5 x 10(-3) min(-1)). A modified mechanism, in which HO center dot are less relevant that at the acidic medium, is in agreement with results of experiments carried out with chemical probes. (C) 2012 Elsevier B.V. All rights reserved.Gomis Vicens, J.; Vercher Pérez, RF.; Amat Payá, AM.; Martire, DO.; Gonzalez, MC.; Prevot, AB.; Montoneri, E.... (2013). Application of soluble bio-organic substances (SBO) as photocatalysts for wastewater treatment: Sensitizing effect and photo-Fenton-like process. Catalysis Today. 209:176-180. doi:10.1016/j.cattod.2012.08.036S17618020

Current clinical applications of spectral tissue Doppler echocardiography (E/E' ratio) as a noninvasive surrogate for left ventricular diastolic pressures in the diagnosis of heart failure with preserved left ventricular systolic function

Congestive heart failure with preserved left ventricular systolic function has emerged as a growing epidemic medical syndrome in developed countries, which is characterized by high morbidity and mortality rates. Rapid and accurate diagnosis of this condition is essential for optimizing the therapeutic management. The diagnosis of congestive heart failure is challenging in patients presenting without obvious left ventricular systolic dysfunction and additional diagnostic information is most commonly required in this setting. Comprehensive Doppler echocardiography is the single most useful diagnostic test recommended by the ESC and ACC/AHA guidelines for assessing left ventricular ejection fraction and cardiac abnormalities in patients with suspected congestive heart failure, and non-invasively determined basal or exercise-induced pulmonary capillary hypertension is likely to become a hallmark of congestive heart failure in symptomatic patients with preserved left ventricular systolic function. The present review will focus on the current clinical applications of spectral tissue Doppler echocardiography used as a reliable noninvasive surrogate for left ventricular diastolic pressures at rest as well as during exercise in the diagnosis of heart failure with preserved left ventricular systolic function. Chronic congestive heart failure, a disease of exercise, and acute heart failure syndromes are characterized by specific pathophysiologic and diagnostic issues, and these two clinical presentations will be discussed separately

Mejoras en el diseño agronómico de la instalación de riego dirigidas al aumento de la productividad técnica y económica del agua en limonero temprano

El objetivo del trabajo fue incrementar la productividad en limonero temprano mediante mejoras en el diseño agronómico de la red de riego. El ensayo se llevó a cabo en una parcela experimental en Torre Pacheco (Murcia), en árboles adultos de limonero ‘Fino 49’ injertados sobre Citrus macrophylla Wester. Se han evaluado dos diseños del sistema de riego: diseño convencional (2L), con dos tuberías portagoteros (6 goteros árbol-1); y un diseño con mayor superficie mojada (3L), con tres tuberías (9 goteros árbol-1). Partiendo de los resultados agronómicos, se ha realizado un análisis económico comparativo entre dos diseños del sistema de riego. El diseño 3L fue el más productivo técnica y económicamente. El Producto Bruto Económico (PBE) fue un 14% superior en el diseño 3L respecto al 2L; el Producto Bruto Técnico (PBT) lo fue en un 6,2%. Este resultado se debe a dos motivos: por un lado y en mayor medida, al incremento en la proporción de limón de primer corte del diseño 3L y, por otro lado, a la disminución de limón derivado a la industria. El Margen Bruto (MB) sigue la misma pauta que el Producto Bruto (PB), ya que los costes diferenciales (CD) son de poca envergadura. El precio ponderado del kg de limón medio (PBE/PBT) es de 0,367 € kg-1 y 0,341 € kg-1, en 3L y 2L, respectivamente, y supone un ingreso de 2.631 € extras por hectárea y año a favor del sistema 3L. Por último, resaltar que el diseño 3L destaca principalmente por ser es más productivo económicamente, en relación al agua aplicada (€ m-3)