Mineralization of Melanoidin by H₂O₂ Producing Enzymes from Marine Cyanobacteria Oscillatoria boryana BDU 92181

Intracellular enzymes of Oscillatoria boryana BDU 92181 exhibited mineralizing activity on melanoidin, a recalcitrant pigment present in the distillery wastewater. Melanoidin decolourization was postulated to be due to the production of hydrogen peroxide and molecular oxygen released by the cyanobacterium during photosynthesis. The present study was aimed to find out the efficacy of the marine cyanobacterium O. boryana BDU 92181 in producing H2O2 and enzymes involved in hydrogen peroxide production with a view to utilize its potential for decolorization of melanoidin pigment in the distillery effluent. The enzymes involved in the melanoidin degradation have not so far been attempted with cyanobacteria. The results obtained in the present work suggested the activity of the glucose oxidase and Manganese peroxidase enzymes in a marine cyanobacterium Oscillatoria boryana BDU 92181 and whose activity was found to be enhanced in the presence of melanoidin.

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Hydrogen peroxide production and killing of Staphylococcus aureus by human polymorphonuclear leukocytes

Blood ◽

10.1182/blood.v49.3.437.437 ◽

1977 ◽

Vol 49 (3) ◽

pp. 437-444 ◽

Cited By ~ 21

Author(s):

MF Tsan ◽

KH Douglass ◽

PA McIntyre

Keyword(s):

Hydrogen Peroxide ◽

Staphylococcus Aureus ◽

Horseradish Peroxidase ◽

Polymorphonuclear Leukocytes ◽

H2o2 Production ◽

Intracellular Killing ◽

Hydrogen Peroxide Production ◽

Production Of Hydrogen ◽

Human Polymorphonuclear Leukocytes ◽

Stimulation Of

Abstract The effects of bacterial neuraminidase on production of hydrogen peroxide (H2O2) and killing of Staphylococcus aureus by human polymorphonuclear leukocytes (PMN) were studied. The concentration of H2O2 was measured by the disappearance of scopoletin fluorescence in the presence of horseradish peroxidase. The results indicated that desialylation of human PMN inhibited the stimulation of H2O2 production during phagocytosis. It also markedly impaired the killing of S. aureus. Impaired killing of S. aureus by desialylated PMN was due to impaired intracellular killing rather than defective phagocytosis.

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Hydrogen peroxide production and killing of Staphylococcus aureus by human polymorphonuclear leukocytes

Blood ◽

10.1182/blood.v49.3.437.bloodjournal493437 ◽

1977 ◽

Vol 49 (3) ◽

pp. 437-444

Author(s):

MF Tsan ◽

KH Douglass ◽

PA McIntyre

Keyword(s):

Hydrogen Peroxide ◽

Staphylococcus Aureus ◽

Horseradish Peroxidase ◽

Polymorphonuclear Leukocytes ◽

H2o2 Production ◽

Intracellular Killing ◽

Hydrogen Peroxide Production ◽

Production Of Hydrogen ◽

Human Polymorphonuclear Leukocytes ◽

Stimulation Of

The effects of bacterial neuraminidase on production of hydrogen peroxide (H2O2) and killing of Staphylococcus aureus by human polymorphonuclear leukocytes (PMN) were studied. The concentration of H2O2 was measured by the disappearance of scopoletin fluorescence in the presence of horseradish peroxidase. The results indicated that desialylation of human PMN inhibited the stimulation of H2O2 production during phagocytosis. It also markedly impaired the killing of S. aureus. Impaired killing of S. aureus by desialylated PMN was due to impaired intracellular killing rather than defective phagocytosis.

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Manganese Peroxidase-Dependent Oxidation of Glyoxylic and Oxalic Acids Synthesized by Ceriporiopsis subvermispora Produces Extracellular Hydrogen Peroxide

Applied and Environmental Microbiology ◽

10.1128/aem.64.1.68-73.1998 ◽

1998 ◽

Vol 64 (1) ◽

pp. 68-73 ◽

Cited By ~ 94

Author(s):

Ulises Urzúa ◽

Philip J. Kersten ◽

Rafael Vicuña

Keyword(s):

Hydrogen Peroxide ◽

Organic Acids ◽

Manganese Peroxidase ◽

Specific Activity ◽

Extracellular Fluid ◽

In Vitro Assays ◽

Phenol Red ◽

Ceriporiopsis Subvermispora ◽

Production Of Hydrogen

ABSTRACT The ligninolytic system of the basidiomycete Ceriporiopsis subvermispora is composed of manganese peroxidase (MnP) and laccase. In this work, the source of extracellular hydrogen peroxide required for MnP activity was investigated. Our attention was focused on the possibility that hydrogen peroxide might be generated by MnP itself through the oxidation of organic acids secreted by the fungus. Both oxalate and glyoxylate were found in the extracellular fluid ofC. subvermispora cultures grown in chemically defined media, where MnP is also secreted. The in vivo oxidation of oxalate was measured; 14CO2 evolution was monitored after addition of exogenous [14C]oxalate to cultures at constant specific activity. In standard cultures, evolution of CO2 from oxalate was maximal at day 6, although the MnP titers were highest at day 12, the oxalate concentration was maximal (2.5 mM) at day 10, and the glyoxylate concentration was maximal (0.24 mM) at day 5. However, in cultures containing low nitrogen levels, in which the pH is more stable, a better correlation between MnP titers and mineralization of oxalate was observed. Both MnP activity and oxidation of [14C]oxalate were negligible in cultures lacking Mn(II). In vitro assays confirmed that Mn(II)-dependent oxidation of [14C]oxalate by MnP occurs and that this reaction is stimulated by glyoxylate at the concentrations found in cultures. In addition, both organic acids supported phenol red oxidation by MnP without added hydrogen peroxide, and glyoxylate was more reactive than oxalate in this reaction. Based on these results, a model is proposed for the extracellular production of hydrogen peroxide by C. subvermispora.

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A catalyst design for selective electrochemical reactions: direct production of hydrogen peroxide in advanced electrochemical oxidation

Journal of Materials Chemistry A ◽

10.1039/d0ta01869d ◽

2020 ◽

Vol 8 (19) ◽

pp. 9859-9870 ◽

Cited By ~ 2

Author(s):

Young-Jin Ko ◽

Keunsu Choi ◽

Boram Yang ◽

Woong Hee Lee ◽

Jun-Yong Kim ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Electrochemical Oxidation ◽

Catalyst Design ◽

Electrochemical Reactions ◽

Attractive Alternative ◽

Hydrogen Peroxide Production ◽

Direct Production ◽

Production Of Hydrogen ◽

Commercial Process

Hydrogen peroxide production by enhanced electrocatalysts is an attractive alternative to the present commercial process.

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Photoelectrocatalytic Hydrogen Peroxide Production Using Nanoparticulate WO3 as Photocatalyst and Glycerol or Ethanol as Sacrificial Agents

Processes ◽

10.3390/pr8010037 ◽

2019 ◽

Vol 8 (1) ◽

pp. 37 ◽

Cited By ~ 1

Author(s):

Ioannis Papagiannis ◽

Nikolaos Balis ◽

Vassilios Dracopoulos ◽

Panagiotis Lianos

Keyword(s):

Hydrogen Peroxide ◽

Carbon Black ◽

Visible Spectrum ◽

Carbon Cloth ◽

Organic Fuel ◽

Hydrogen Peroxide Production ◽

Faradaic Efficiency ◽

Production Of Hydrogen ◽

A Cell ◽

Sacrificial Agent

Photoelectrochemical production of hydrogen peroxide was studied by using a cell functioning with a WO3 photoanode and an air breathing cathode made of carbon cloth with a hydrophobic layer of carbon black. The photoanode functioned in the absence of any sacrificial agent by water splitting, but the produced photocurrent was doubled in the presence of glycerol or ethanol. Hydrogen peroxide production was monitored in all cases, mainly in the presence of glycerol. The presence or absence of the organic fuel affected only the obtained photocurrent. The Faradaic efficiency for hydrogen peroxide production was the same in all cases, mounting up to 74%. The duplication of the photocurrent in the presence of biomass derivatives such as glycerol or ethanol and the fact that WO3 absorbed light in a substantial range of the visible spectrum promotes the presently studied system as a sustainable source of hydrogen peroxide production.

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In vitro immunitary impact and antioxidant activity of aqueous extracts of Maprounea africana Müll (Euphorbiaceae) and Mitragyna stipulosa O.Kze (Rubiaceae)

The Journal of Phytopharmacology ◽

10.31254/phyto.2017.6501 ◽

2017 ◽

Vol 6 (5) ◽

pp. 260-263

Author(s):

Morabandza Cyr Jonas ◽

◽

Nkounkou Loupangou Celestine ◽

Etou Ossibi Arnaud Wilfrid ◽

Ongoka Pascal Robin ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Antioxidant Activity ◽

Aqueous Extract ◽

Stem Bark ◽

Aqueous Extracts ◽

Hydrogen Peroxide Production ◽

Total Lymphocyte ◽

Production Of Hydrogen ◽

New Compounds

This study aims to investigate the in vitro immunitary impacts and antioxidant activity of aqueous extracts of Maprounea africana (Euphorbiaceae) leaves and Mitragyna stipulosa (Rubiaceae) stem barks. Impact on leukocyte cells (total lymphocyte, polynuclears, monocyte, NK, TCD8 and TCD4) was quantified by using flow cytometry and, antioxidant activity by quantification of hydrogen peroxide production after immunomarking of specific monoclonal antibodies. The results showed a significant descrease of total lymphocyte, polynuclear, NK, TCD8 and, a non-significant descrease of TCD4 and monocyte induces by aqueous extract of M. africana leaves. Whereas aqueous extract of the stem bark of M. stipulosa induces a significant increase of total lymphocyte, TCD4, NK, TCD8 and, a significant descrease of polynuclear and monocyte. The two extracts significantly reduce (p˂0.001) the production of hydrogen peroxid by polynuclear, lymphocytes and monocytes. These results suggest an immunomodulatory and immunostimulant effect of M. africana and M. stipulosa respectively and, antioxidant activity. The present study established pharmacological evidence to support traditional uses of these two species and may open up the possibility of finding the new compounds against immunological desseases.

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