scholarly journals Alternative use of Pseudomonas aeruginosa as indicator for greywater disinfection

2018 ◽  
Vol 78 (6) ◽  
pp. 1361-1369 ◽  
Author(s):  
Anderson Teodoro ◽  
Amilcar Machulek Júnior ◽  
Marc Árpád Boncz ◽  
Paula Loureiro Paulo
Keyword(s):  
Hydrogen Peroxide ◽  
Pseudomonas Aeruginosa ◽  
Solar Radiation ◽  
Acute Toxicity ◽  
High Resistance ◽  
Surfactant Concentration ◽  
Advanced Oxidation ◽  
Natural Concentration ◽  
Log Linear ◽  
Uv Lamps

Abstract Greywater presents great potential for reuse; if treated correctly and efficiently, it can be used for several residential uses. The objective of this work was to test advanced oxidation for greywater disinfection through UV/TiO2, UV/TiO2/H2O2, photo-Fenton, UV/H2O2 and photolysis (UV) processes, using Pseudomonas aeruginosa as an alternative indicator. In general, the processes with hydrogen peroxide (150 mg.L−1) mixed in the pretreated greywater and exposed to solar radiation or artificial radiation from UV lamps were the most efficient in the disinfection experiments, with total inactivation of P. aeruginosa. These processes (UV/H2O2 and photo-Fenton) were better fitted to the log-linear/caudal decay model with remaining microorganism for the hydrogen peroxide concentration of 25 mg.L−1. The use of P. aeruginosa as an alternative indicator for the greywater disinfection was very promising due to its high resistance and high natural concentration in the effluent used in the experiments. The treatment applied with the UV/H2O2 process with the hydrogen peroxide concentration at 150 mg.L−1 was the only one that showed acute toxicity, even though it removed a good part of the surfactant concentration from the pre-treated greywater.

Chemical Models of Advanced Oxidation Processes

1992 ◽  
Vol 27 (1) ◽  
pp. 23-42 ◽  
Author(s):  
William H. Glaze ◽  
Fernando Beltran ◽  
Tuula Tuhkanen ◽  
Joon-Wun Kang
Keyword(s):  
Hydrogen Peroxide ◽  
Advanced Oxidation Processes ◽  
Advanced Oxidation ◽  
Industrial Wastes ◽  
Organic Substances ◽  
Ultrapure Water ◽  
Radical Scavengers ◽  
Oxidation Processes ◽  
Radical Intermediates ◽  
Chemical Models

Abstract Advanced oxidation processes (AOPs) have been defined as near-ambient temperature processes that involve the generation of highly reactive radical intermediates, especially the hydroxyl radical. These processes show promise for the destruction of hazardous organic substances in municipal and industrial wastes, in drinking water and in ultrapure water. Three types of AOPs are considered in this paper: catalyzed decomposition of ozone; ozone with hydrogen peroxide (Peroxone); and photolysis of hydrogen peroxide with ultraviolet radiation. Kinetic models for these processes are being developed based on known chemical and photochemical principles. The models take into account measured effects of radical scavengers such as bicarbonate; dose ratios of the oxidants or UV intensity; pH; and the presence of generic radical scavengers. The models are used to discuss two cases: oxidation of parts-per-million levels of nitrobenzene with ozone, Peroxone and peroxide/UV and oxidation of naphthalene and pentachlorophenol with peroxide/UV.

scholarly journals Effect of pH on the Electrochemical Behavior of Hydrogen Peroxide in the Presence of Pseudomonas aeruginosa

2021 ◽  
Vol 9 ◽  
Author(s):  
Javier Espinoza-Vergara ◽  
Paulo Molina ◽  
Mariana Walter ◽  
Miguel Gulppi ◽  
Nelson Vejar ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Pseudomonas Aeruginosa ◽  
Enzymatic Activity ◽  
Electrochemical Behavior ◽  
Electrochemical Techniques ◽  
Stable State ◽  
Reduction Reaction ◽  
Maximum Activity ◽  
Open Circuit ◽  
Mueller Hinton

The influence of pH on the electrochemical behavior of hydrogen peroxide in the presence of Pseudomonas aeruginosa was investigated using electrochemical techniques. Cyclic and square wave voltammetry were used to monitor the enzymatic activity. A modified cobalt phthalocyanine (CoPc) carbon electrode (OPG), a known catalyst for reducing O2 to H2O2, was used to detect species resulting from the enzyme activity. The electrolyte was a sterilized aqueous medium containing Mueller-Hinton (MH) broth. The open-circuit potential (OCP) of the Pseudomonas aeruginosa culture in MH decreased rapidly with time, reaching a stable state after 4 h. Peculiarities in the E / I response were observed in voltammograms conducted in less than 4 h of exposure to the culture medium. Such particular E/I responses are due to the catalase’s enzymatic action related to the conversion of hydrogen peroxide to oxygen, confirming the authors’ previous findings related to the behavior of other catalase-positive microorganisms. The enzymatic activity exhibits maximum activity at pH 7.5, assessed by the potential at which oxygen is reduced to hydrogen peroxide. At higher or lower pHs, the oxygen reduction reaction (ORR) occurs at higher overpotentials, i.e., at more negative potentials. In addition, and to assess the influence of bacterial adhesion on the electrochemical behavior, measurements of the bacterial-substrate metal interaction were performed at different pH using atomic force microscopy.

Phytochemical Content, Radical Scavenging and Antibacterial Properties of Aqueous Extract of Jatropha curcas Linn Leaves

2012 ◽  
Vol 1 (1) ◽  
Author(s):  
O B Oloyede
Keyword(s):  
Escherichia Coli ◽  
Hydrogen Peroxide ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Aqueous Extract ◽  
Jatropha Curcas ◽  
Radical Scavenging ◽  
Klebsiella Pneumonia ◽  
Phytochemical Content ◽  
Proteus Species

This study investigated phytochemical content, radical scavenging and antibacterial activities of aqueous extract of leaves of Jatropha curcas Linn. Quantitative phytochemical analyses of alkaloids, phenols, tannins and flavonoids contents were carried out; radical scavenging activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and hydrogen peroxide inhibition assays while Disc diffusion and Agar well (ditch) diffusion methods were used for antibacterial activity against Klebsiella pneumonia, Escherichia coli, Pseudomonas aeruginosa, Staphilococcus aureus and Proteus species at 62.5, 125, 250 and 500 mg/mL. The extract contained alkaloids (1.600± 0.58 %), tannins (0.121 ± 0.00 mg/mL), phenols (0.463 ± 0.06 mg/mL) and flavonoids (0.672 ± 0.00 mg/mL), and showed radical scavenging activities against DPPH (IC50 = 21.24) and hydrogen peroxide (15.67 mg/mL) which were less than that of Butylated hydroxyanisole (BHA); IC50 = 3.92 (DPPH) and 6.19 mg/mL (hydrogen peroxide) respectively. It also showed antibacterial activity against Klebsiella pneumonia, Escherichia coli, and Pseudomonas aeruginosa at 250 and 500 mg/ml (MIC = 125 mg/mL), which were resistant to ampicillin, chloxacillin and erythromycin, and the extract was inactive against Staphilococcus aureus and Proteus species at these concentrations, though all were sensitive to gentamycin. This shows that the aqueous extract of leaves of Jatropha curcas Linn may possess some of the folkloric properties claimed.

Combinative dyebath treatment with activated carbon and UV/H2O2: a case study on Everzol Black-GSP®

2002 ◽  
Vol 46 (4-5) ◽  
pp. 51-58 ◽  
Author(s):  
N.H. Ince ◽  
D.A. Hasan ◽  
B. Üstün ◽  
G. Tezcanli
Keyword(s):  
Hydrogen Peroxide ◽  
Activated Carbon ◽  
Carbon Mineralization ◽  
Oxidative Degradation ◽  
Advanced Oxidation ◽  
Color Removal ◽  
Operating Parameters ◽  
Cost Reductions ◽  
H2o2 System

Treatability of textile dyebath effluents by two simultaneously operated processes comprising adsorption and advanced oxidation was investigated using a reactive dyestuff, Everzol Black-GSP® (EBG). The method was comprised of contacting aqueous solutions of the dye with hydrogen peroxide and granules of activated carbon (GAC) during irradiation of the reactor with ultraviolet light (UV). Control experiments were run separately with each individual process (advanced oxidation with UV/H2O2 and adsorption on GAC) to select the operating parameters on the basis of maximum color removal. The effectiveness of the combined scheme was tested by monitoring the rate of decolorization and the degree of carbon mineralization in effluent samples. It was found that in a combined medium of advanced oxidation and adsorption, color was principally removed by oxidative degradation, while adsorption contributed to the longer process of dye mineralization. Economic evaluation of the system based on total color removal and 50% mineralization showed that in the case of Everzol Black-GSP®, which adsorbs relatively poorly on GAC, the proposed combination provides 25% and 35% reduction in hydrogen peroxide and energy consumption relative to the UV/H2O2 system. Higher cost reductions are expected in cases with well adsorbing dyes and/or with less costly adsorbents.

Optimizing Potable Water Reuse Systems: Chloramines or Hydrogen Peroxide for UV-Based Advanced Oxidation Process?

2019 ◽  
Vol 53 (22) ◽  
pp. 13323-13331 ◽  
Author(s):  
Kiranmayi P. Mangalgiri ◽  
Samuel Patton ◽  
Liang Wu ◽  
Shanhui Xu ◽  
Kenneth P. Ishida ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Water Reuse ◽  
Potable Water ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Advanced Oxidation
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