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1.
Braz J Microbiol ; 55(1): 471-485, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38052770

ABSTRACT

Microorganisms that inhabit the cold Antarctic environment can produce ligninolytic enzymes potentially useful in bioremediation. Our study focused on characterizing Antarctic bacteria and fungi from marine sediment samples of King George and Deception Islands, maritime Antarctica, potentially affected by hydrocarbon influence, able to produce enzymes for use in bioremediation processes in environments impacted with petroleum derivatives. A total of 168 microorganism isolates were obtained: 56 from sediments of King George Island and 112 from Deception Island. Among them, five bacterial isolates were tolerant to cell growth in the presence of diesel oil and gasoline and seven fungal were able to discolor RBBR dye. In addition, 16 isolates (15 bacterial and one fungal) displayed enzymatic emulsifying activities. Two isolates were characterized taxonomically by showing better biotechnological results. Psychrobacter sp. BAD17 and Cladosporium sp. FAR18 showed pyrene tolerance (cell growth of 0.03 g mL-1 and 0.2 g mL-1) and laccase enzymatic activity (0.006 UL-1 and 0.10 UL-1), respectively. Our results indicate that bacteria and fungi living in sediments under potential effect of hydrocarbon pollution may represent a promising alternative to bioremediate cold environments contaminated with polluting compounds derived from petroleum such as polycyclic aromatic hydrocarbons and dyes.


Subject(s)
Microbiota , Petroleum , Polycyclic Aromatic Hydrocarbons , Antarctic Regions , Biodegradation, Environmental , Bioprospecting , Hydrocarbons , Gasoline , Geologic Sediments/microbiology , Bacteria/genetics
2.
J Sci Food Agric ; 103(11): 5578-5587, 2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37063086

ABSTRACT

BACKGROUND: The importance of pollination is recognized worldwide. This study investigates the influence of biotic pollination on the chemical composition of coffee (Coffea arabica L.) cultivated in the municipalities of Araguari and Monte Carmelo, in Minas Gerais state, Brazil. Twenty samples were analyzed, of which 10 were biotically pollinated (P) and 10 non-biotically pollinated (NP). Analyses of bioactive compounds, antioxidant capacity and centesimal composition of coffees were performed. RESULTS: The results revealed chemical differences between the P and NP samples, with significantly higher levels of the bioactive compounds caffeine, trigonelline, and chlorogenic acids in the P samples. The findings indicated that pollination of the coffee plants assisted germination and made the beans less susceptible to attack by external agents. CONCLUSION: The results demonstrated that pollination services are important mechanisms affecting the chemical composition of coffee beans. Considering that the compounds evaluated are precursors of volatile compounds in coffee, this directly affects the quality of the beans. © 2023 Society of Chemical Industry.


Subject(s)
Antioxidants , Coffea , Antioxidants/chemistry , Coffea/chemistry , Pollination , Seeds/chemistry , Caffeine/analysis
3.
MethodsX ; 9: 101774, 2022.
Article in English | MEDLINE | ID: mdl-35813162

ABSTRACT

HMF (hydroxymethylfurfural), a compound that occurs naturally in food, is derived from the dehydration of monosaccharides (glucose and fructose) in products subjected to high-temperature treatments or to aging processes. HMF can be obtained by acid-catalyzed dehydration of lignocellulosic biomasses such as sugarcane bagasse and other agricultural residues. In this work, analytical quantification of HMF and furfural (the main co-product) was performed using high-performance liquid chromatography coupled with diode array detection (HPLC-DAD). The official method employs isocratic elution with a mobile phase composed of water and acetonitrile at a ratio of 80:20 (v/v). The analytical method proposed here was developed using 2,5-furandicarboxylic acid (FDCA) as internal standard, for the first time, with 0.01 mol L-1 trisodium citrate and ultrapure water as the mobile phase, adjusted to pH 2.5. The acidity of the mobile phase was required to avoid FDCA deprotonation. Good peak resolution and selectivity were obtained, without differences in the retention times of the analytes present in the standard solutions used to obtain the analytical curve and in the aqueous and organic phases from the synthesis of HMF using lignocellulosic biomass hydrolysis. The method complies with the current recommendations of AOAC regarding validation parameters.•The proposed HPLC method improves peak selectivity and resolution.•The method is suitable for acid sample media, such as aqueous and organic hydrolysis phases.•2,5-Furandicarboxylic acid (FDCA) was used as internal standard.

4.
An Acad Bras Cienc ; 94(2): e20201718, 2022.
Article in English | MEDLINE | ID: mdl-35674605

ABSTRACT

The inappropriate disposal of toxic compounds generated by industrial activity has considerably impacted the environment. Microbial communities inhabiting contaminated sites may represent ecological alternatives for the decontamination of environments. The present work aimed to search the potential of fungi isolated from wastewater treatment plant of a textile industry for bioremediation processes. Twenty-three fungi previously isolated from textile effluent were evaluated for their abilities to degrade pollutants using heavy metal and hydrocarbon tolerance assays. One isolate was subjected to pyrene degradation due its ability to tolerate hydrocarbon. The majority of isolates were resistant to at least two metals tested, i.e. chrome, copper, lead and aluminum. Isolates Penicillium sp. ITF 2, Penicillium rubens ITF 4, Penicillium sp. ITF 12 and ITF 20 (not identified) showed tolerance to tested heavy metals in all concentrations. ITF 12 and ITF 20 were able to tolerate benzene, toluene and hexane, separately. ITF 12 was able to degrade 24.9% of pyrene after 5 days of cultivation. The results encourage future studies to optimize the tolerance and degradation assay using the isolates that showed the best results, as well as studies on the treatment of environments contaminated with heavy metals and hydrocarbons, including industrial textile effluents.


Subject(s)
Fungi , Metals, Heavy , Biodegradation, Environmental , Metals, Heavy/analysis , Pyrenes/metabolism , Textiles
5.
An Acad Bras Cienc ; 94(2): e20201718, 2022.
Article in English | MEDLINE | ID: mdl-35703692

ABSTRACT

The inappropriate disposal of toxic compounds generated by industrial activity has considerably impacted the environment. Microbial communities inhabiting contaminated sites may represent ecological alternatives for the decontamination of environments. The present work aimed to search the potential of fungi isolated from wastewater treatment plant of a textile industry for bioremediation processes. Twenty-three fungi previously isolated from textile effluent were evaluated for their abilities to degrade pollutants using heavy metal and hydrocarbon tolerance assays. One isolate was subjected to pyrene degradation due its ability to tolerate hydrocarbon. The majority of isolates were resistant to at least two metals tested, i.e. chrome, copper, lead and aluminum. Isolates Penicillium sp. ITF 2, Penicillium rubens ITF 4, Penicillium sp. ITF 12 and ITF 20 (not identified) showed tolerance to tested heavy metals in all concentrations. ITF 12 and ITF 20 were able to tolerate benzene, toluene and hexane, separately. ITF 12 was able to degrade 24.9% of pyrene after 5 days of cultivation. The results encourage future studies to optimize the tolerance and degradation assay using the isolates that showed the best results, as well as studies on the treatment of environments contaminated with heavy metals and hydrocarbons, including industrial textile effluents.


Subject(s)
Fungi , Metals, Heavy , Biodegradation, Environmental , Metals, Heavy/analysis , Pyrenes/metabolism , Textiles
6.
J Sci Food Agric ; 102(11): 4955-4960, 2022 Aug 30.
Article in English | MEDLINE | ID: mdl-35018655

ABSTRACT

BACKGROUND: Pollination enhances coffee quality at the material level, improves the symbolic attributes of coffee and promotes sustainability. The objective of this work was to quantify the composition of volatile compounds in roasted coffee produced in the presence and absence of biotic pollination, aiming at investigating the effects of pollination on the composition of volatile compounds in coffee beans. This is the first report of its kind in the literature. RESULTS: The analysis of volatile compounds in roasted coffee beans showed that pollination increased the amount of volatile compounds in the beans; there was a significant increase in the amount of the following classes of compounds: pyrazines, pyrroles, pyridines, alcohols and phenols. Considering that most volatile compounds in roasted coffee are derived from reactions involving carbohydrates, proteins, chlorogenic acids and some alkaloids, our hypothesis is that pollinated coffee beans are better prepared for germination and for defense of the crop against attack by external agents. CONCLUSION: The findings of this study point to the important role played by sustainable practices implemented in coffee cultivation. The results obtained in this study pave the way toward the conduct of further investigations, including the analysis of the chemical composition of aroma precursors and volatile compounds in raw coffee beans, and the study of the sensory aspects of roasted coffee. © 2022 Society of Chemical Industry.


Subject(s)
Coffea , Coffea/chemistry , Food Handling/methods , Odorants/analysis , Pollination , Seeds/chemistry
7.
Rev. chil. nutr ; 48(6)dic. 2021.
Article in English | LILACS-Express | LILACS | ID: biblio-1388550

ABSTRACT

ABSTRACT The present study aims to establish the fatty acid profile of a variety of traditional foods consumed regularly in Paraguay. Thirty-two high-lipid content foods were evaluated by gas chromatography coupled with a flame ionization detector (GC-FID). Meat and dairy products were found to present high levels of saturated fatty acids, and this led to an increase in the atherogenicity and thrombogenicity indices of these products. Among the monounsaturated acids evaluated, oleic acid (18:1n-9c) was mainly found in olives (71.7%) and chipa (62.7%), which had been industrially prepared with the addition of oleic acid. Milk-based ice cream (5.1%) and chipa guazú (3.8%) presented the highest content of trans fatty acids. The n-6/n-3 fatty acids ratio obtained for the traditional sopa Paraguaya and empanada (fried pasty) was higher than 37:1; this can be attributed to the addition of soybean and corn oils in the preparation of these foods. The data evaluated and presented in this study can contribute toward the improvement of eating habits among the Paraguayan population, as well as help combat the risk factors commonly associated with bad eating habits and chronic health issues.


RESUMEN El presente estudio tuvo como objetivo establecer los perfiles de ácidos grasos de una variedad de alimentos tradicionales que se consumen regularmente en Paraguay. Se evaluaron treinta y dos alimentos con alto contenido de lípidos mediante cromatografía de gases acoplada a detector de ionización de llama (GC-FID). Los productos cárnicos y lácteos presentaron un elevado nivel de ácidos grasos saturados, aumentando los índices de aterogenicidad y trombogenicidad. Entre los monoinsaturados, el ácido oleico (18: 1n-9c) se encuentró principalmente en aceitunas (71,7%) y chipa (62,7%), este último preparado industrialmente por adición de ácido oleico. En cuanto al contenido de ácidos grasos trans, los valores más altos se encontraron en los helados a base de leche (5,1%) y chipa guazú (3,8%). Los valores de la relación n-6 / n-3 fueron superiores a 37:1 en sopa paraguaya y empanada (frita) debido a la adición de aceite de soja y maíz utilizado en la preparación de alimentos. Los datos evaluados y presentados en este estudio pueden contribuir a la mejora de los hábitos alimentarios de la población paraguaya, así como ayudar a combatir los factores de riesgo comúnmente asociados con los malos hábitos alimentarios y los problemas crónicos de salud.

8.
Curr Microbiol ; 78(1): 358-368, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33230622

ABSTRACT

The intense use of pesticides in agricultural activities for the last several decades has caused contamination of the ecosystems connected with crop fields. Despite the well-documented occurrence of pesticide biodegradation by microbes, natural attenuation of atrazine (ATZ), and its effects on ecological processes in subtropical forested areas, such as Iguaçu National Park located in Brazil, has been poorly investigated. Subtropical environments sustain a great degree of fungal biodiversity, and the patterns and roles of these organisms should be better understood. This work aimed to evaluate nine ligninolytic-producer fungi isolated from the INP edge to degrade and detoxify ATZ solutions. ATZ degradation and the main metabolites produced, including deisopropylatrazine and deethylatrazine (DEA), were analyzed using dispersive liquid-liquid microextraction followed by gas chromatography-mass spectrometer. Four fungi were able to degrade ATZ to DEA, and the other five showed potential to grow and facilitate ATZ biodegradation. Furthermore, two strains of Fusarium spp. showed an enhanced potential for detoxification according to the Allium cepa (onion) test. Although the isolates produced ligninolytic enzymes, no ligninolytic activity was observed in the biodegradation of ATZ, a feature with ecological significance. In conclusion, Ascomycota fungi from the INP edge can degrade and detoxify ATZ in solution. Increasing the knowledge of biodiversity in subtropical protected areas, such as ecosystem services provided by microbes, enhances ecosystem conservation.


Subject(s)
Atrazine , Herbicides , Brazil , Ecosystem , Fungi/genetics , Plant Leaves
9.
Int J Vitam Nutr Res ; 91(5-6): 461-468, 2021 Sep.
Article in English | MEDLINE | ID: mdl-32138619

ABSTRACT

Dairy beverages containing emulsified linseed oil is a suitable vehicle for delivering polyunsaturated fatty acids to consumers. However, these beverages are prone to oxidation. The purpose of this study was to evaluate the effect of adding various concentrations (0, 0.001, 0.01 and 0.1% (w/w)) of green tea extract (GTE) to dairy beverages (DB) containing linseed oil (2.0%, w/w), in order to inhibit lipid oxidation during storage at high temperature (50 °C) or under fluorescent light exposure. During storage, the concentration of catechin (C), epicatechin (EC) and epicatechin gallate (ECG) were significantly reduced (P ≤ 0.05) and degradation rate was greater when the DB were exposed to light (C 35%, EC 74% and ECG 68%) as compared to high temperature (C 34%, EC 45% and ECG 49%). In DB without GTE, the conjugated dienes (CD) hydroperoxides concentration increased significantly (P ≤ 0.05) from 23 mmol kg-1 fat to 243 mmol kg-1 fat under 6-day-light exposition, and to 83 mmol kg-1 fat under 6-day-heat temperature. The addition of GTE significantly increased the antioxidant capacity of DB and reduced the formation of CD, propanal and hexanal, induced by light exposure or high temperature. GTE at 0.10% completely inhibited CD formation during the storage period and reduced propanal and hexanal concentrations below the threshold.


Subject(s)
Catechin , Beverages , Linseed Oil , Plant Extracts , Tea
10.
J Environ Sci Health B ; 55(10): 909-920, 2020.
Article in English | MEDLINE | ID: mdl-33084505

ABSTRACT

Glyphosate is the main herbicide used in soybean crops, and Brazil is one of the major soybean producers around the world. GLY and AMPA were evaluated in 124 surface waters samples of twenty one micro basins in Paraná Basin 3 (State of Parana, Brazil) over six subsequent weeks. A simple and economical routine methodology was established, based on lyophilization as a pre-concentration method. The validated method showed a limit of detection of 0.0125 and 0.025 µg L-1 for GLY and AMPA, respectively. In general, water samples presented concentrations ranging from 0.31 to 1.65 µg L-1 for GLY. Those values are below the maximum allowed amounts in Brazilian Law (65 µg L-1). The AMPA values were found in the range from 0.50 to 1.40 µg L-1. In summary, GLY was detected in 19.3% and it was quantified in 17.7% of the samples. AMPA was detected in 21.8% and it was quantified in 1.6% of the samples. Although samples did not present values higher than the established by Brazilian Law, GLY and AMPA appear constantly in the samples, which highlight the importance of monitoring studies in watersheds.


Subject(s)
Fresh Water/analysis , Glycine/analogs & derivatives , Herbicides/analysis , alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/analysis , Brazil , Chromatography, High Pressure Liquid , Fluorescence , Freeze Drying , Glycine/analysis , Glyphosate
11.
Extremophiles ; 24(6): 863-873, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32944821

ABSTRACT

In the last decades, efforts to reduce the use of fossil fuels have increased the search for alternative sustainable sources of renewable energy. In this scenario, hydrocarbons derived from fatty acids are among the compounds that have been drawing attention. The intracellular production of hydrocarbons by bacteria derived from cold environments such as the Antarctic continent is currently poorly investigated, as extremophilic microorganisms provide a great range of metabolic capabilities and may represent a key tool in the production of biofuels. The aim of this study was to explore the ability of bacterial cells derived from extreme environments to produce hydrocarbons with potential for further use as biofuels. Seven bacteria isolated from Antarctic samples were evaluated for hydrocarbon production using GC-MS approaches. Two isolates, identified as Arthrobacter livingstonensis 593 and Pseudoalteromonas arctica 628, were able to produce the hydrocarbon undecane (CH3-(CH2)9-CH3) in concentrations of 1.39 mg L-1 and 1.81 mg L-1, respectively. Results from the present work encourage further research focusing on the optimization of hydrocarbon production by the isolates identified as producers, which may be used in further aircraft biofuel production. This is the first report on the production of the undecane compound by bacteria isolated from waterlogged soil and sponge from Antarctica.


Subject(s)
Alkanes/metabolism , Arthrobacter/metabolism , Biofuels , Pseudoalteromonas/metabolism , Antarctic Regions , Soil Microbiology
12.
Ciênc. agrotec., (Impr.) ; 35(4): 735-741, ago. 2011. tab
Article in English | LILACS | ID: lil-597695

ABSTRACT

The objective of this study was to quantify alpha-linolenic acid (LNA, 18:3n-3) of dried wheat leaves, harvested at different development stages (20, 40 and 80 days), to determine the antioxidant potential and the total phenolic compounds of leaves harvested at 80 days, as well as to perform mineral analysis (Na, K, Fe, Ca, Mg, P, Zn, Cu and Mn). It was observed a predominance of polyunsaturated fatty acids (PUFA) compared to saturated fatty acids (SFA) in the lipid fraction of leaves. Leaves collected in all periods presented ratios of PUFA/SFA, omega-6 and omega-3 fatty acids (n-6/n-3) considered suitable for food. The highest content of LNA was found in leaves harvested at 60 days, corresponding to 2.146,72 mg 100 g-1 dried matter. The range time between 60 and 80 days showed a decline of nearly 30 percent in the concentration of LNA. The acetate fraction was the most effective over DPPH radical assay, showing IC50 value of 154 µg mL-1, and the phenolic compounds content was 615.4 ± 36.4 mg EAG L-1, both analyses carried out in leaves harvested at 80 days. In this development stage, wheat leaves showed significant levels of the minerals P, Zn, Cu and Mn. These results reinforce the potential of using wheat leaves in foods, according to its antioxidant content and significant levels of LNA.


Conduziu-se este estudo, com o objetivo de quantificar o ácido alfa-linolênico (LNA, 18:3n-3) em folhas de trigo secas e colhidas em diferentes estádios de desenvolvimento (20, 40 e 80 dias), determinar o potencial antioxidante e o conteúdo de fenólicos totais em folhas colhidas aos 80 dias, assim como realizar a analise de minerais (Na, K, Fe, Ca, Mg, P, Zn, Cu e Mn). Foi verificada uma predominância de ácidos graxos poli-insaturados (AGPI) comparado com os ácidos graxos saturados (AGS) na fração lipídica das folhas. As folhas colhidas em todos os períodos apresentaram razões de AGPI/AGS e de ácidos graxos ômega-6 e ômega-3 (n-6/n-3), dentro dos valores considerados adequados para a alimentação. O maior teor de LNA foi encontrado nas folhas colhidas aos 60 dias, correspondendo a 2.146,72 mg 100 g-1 de matéria seca. Entre 60 e 80 dias, observou-se uma queda de cerca de 30 por cento na concentração de LNA. A fração acetato foi eficiente na inibição do radical DPPH, apresentando valor de IC50 de 154 µg mL-1, e o teor de compostos fenólicos foi de 615,4 ± 36,4 mg EAG L-1, ambas as análises para as folhas colhidas aos 80 dias. Nesse estádio de crescimento, as folhas apresentaram consideráveis teores dos minerais P, Zn, Cu e Mn. Tais resultados reforçam a importância do uso de folhas de trigo para alimentação humana, em função de seu potencial antioxidante e consideráveis teores de LNA.

13.
Ciênc. agrotec., (Impr.) ; 34(6): 1500-1506, nov.-dez. 2010. tab
Article in Portuguese | LILACS | ID: lil-572324

ABSTRACT

O objetivo deste estudo foi quantificar o ácido alfa-linolênico [LNA, 18:3 (n-3)], avaliar a composição centesimal das folhas e caules de linho (Linum usitatissimum L.) submetidos à secagem e colhidos em diferentes estágios de desenvolvimento (40, 80 e 120 dias), e determinar o potencial antioxidante das folhas colhidas aos 80 dias através do teste com o radical DPPH. As folhas obtiveram maiores teores de cinzas, proteína e lipídios totais em relação aos caules. Tanto as folhas quanto os caules apresentaram razões de AGPI/AGS e n-6/n-3 dentro dos valores considerados adequados para a alimentação. Os caules colhidos nos diferentes tempos não apresentaram diferenças significativas (P<0,05), quanto ao teor de LNA. As folhas colhidas aos 80 dias apresentaram a maior concentração de LNA, correspondendo a 1,262,36 mg/100g de folhas desidratadas. Os diferentes extratos (metanólico, butanólico, acetato e aquoso) foram eficientes na inibição do radical DPPH, com destaque para as frações butanólica e acetato, sendo os valores de IC50 de aproximadamente 42ppm para as duas frações. Tais resultados evidenciaram a atividade antioxidante e potencial nutritivo das folhas e caules de linho para futuro uso na alimentação animal e humana.


The objective of this study was to quantify the alpha-linolenic acid [LNA, 18:3 (n-3)] and to evaluate the proximate composition of leaves and stems of flax (Linum usitatissimum L.) dried and harvested at different stages of development (40, 80 and 120 days), and to determine the antioxidant potential of the leaf harvested at 80 days using the test of DPPH radical. The leaves had higher levels of ash, protein and total lipids when compared to the stems. Both the leaves as the stems had ratios of PUFA/SFA and n-6/n-3 within the values considered suitable for food. Stems in the different stages showed no significant difference (P<0.05) of LNA content. Leaves harvested at 80 days showed the highest concentration of LNA, corresponding to 1,262.36 mg/100g dried leaf. The different extracts (methanol, butanol, acetate and water) were efficient in the inhibition of DPPH radical, with emphasis on the butanolic and acetate fractions and the values of IC50 were approximately 42 ppm. These results highlight the nutritional potential and antioxidant activity of leaves and stems of flaxseed for future use in the animal and human feeding.

14.
J Hazard Mater ; 162(1): 448-54, 2009 Feb 15.
Article in English | MEDLINE | ID: mdl-18573596

ABSTRACT

The treated wastewater consists of refractory materials and high organic content of hydrolyzed peptone residues from pharmaceutical factory. The combination of electrocoagulation (EC) followed by heterogeneous photocatalysis (TiO(2)) conditions was maximized. The EC: iron cathode/anode (12.50 cmx2.50 cmx0.10 cm), current density 763Am(-2), 90min and initial pH 6.0. As EC consequence, the majority of the dissolved organic and suspended material was removed (about 91% and 86% of the turbidity and chemical oxygen demand (COD), respectively). After EC, refractory residues still remained in the effluent. The subsequent photocatalysis: UV/TiO(2)/H(2)O(2) (mercury lamps), pH 3.0, 4h irradiation, 0.25gL(-1) TiO(2) and 10mmolL(-1) H(2)O(2) shows high levels of inorganic and organic compounds eliminations. The obtained COD values: 1753mgL(-1) for the sample from the factory, 160mgL(-1) after EC and 50mgL(-1) after EC/photocatalyzed effluents pointed out that the combined treatment stresses this water purification.


Subject(s)
Cosmetics , Drug Industry , Industrial Waste/analysis , Titanium/chemistry , Waste Disposal, Fluid/methods , Catalysis , Electric Conductivity , Electrochemistry , Hydrogen Peroxide/chemistry , Kinetics , Nephelometry and Turbidimetry , Oxidants/chemistry , Oxygen/analysis , Photochemistry , Spectrophotometry, Ultraviolet
15.
J Hazard Mater ; 160(1): 135-41, 2008 Dec 15.
Article in English | MEDLINE | ID: mdl-18417286

ABSTRACT

Cellulose and paper pulp factories utilize a large amount of water generating several undesirable contaminants. The present work is a preliminary investigation that associates the electrocoagulation-flotation (EC) method followed by photocatalysis to treat such wastewater. For EC, the experiment with aluminium and iron electrodes showed similar efficiency. Iron electrodes (anode and cathode) were chosen. By applying 30min of EC/Fe(0), 153A m(-2) and pH 6.0, the COD values, UV-vis absorbance and turbidity underwent an intense decrease. For the subsequent UV photocatalysis (mercury lamps) TiO(2) was employed and the favourable operational conditions found were 0.25g L(-1) of the catalyst and solution pH 3.0. The addition of hydrogen peroxide (50mmol L(-1)) highly increased the photo-process performance. By employing the UV/TiO(2)/H(2)O(2) system, the COD reduction was 88% compared to pre-treated effluents and complete sample photobleaching was verified. The salt concentration on EC (iron electrodes) showed that the electrolysis duration can be reduced from 30 to 10min by the addition of 5.0g L(-1) of NaCl. The biodegradability index (BOD/COD) increased from 0.15 (pre-treated) to 0.48 (after EC) and to 0.89 (after EC/photocatalysis irradiated for 6h), showing that the employed sequence is very helpful to improve the water quality. This result was confirmed by biotoxicity tests performed with microcrustaceous Artemia salina.


Subject(s)
Cellulose , Industrial Waste/analysis , Paper , Waste Disposal, Fluid/methods , Animals , Artemia , Biodegradation, Environmental , Brazil , Catalysis , Electrochemistry , Indicators and Reagents , Industrial Waste/legislation & jurisprudence , Photochemistry , Titanium/chemistry , Ultraviolet Rays , Waste Disposal, Fluid/legislation & jurisprudence , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
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