Photoenzymatic Hydroxylation of Ethylbenzene Catalyzed by Unspecific Peroxygenase: Origin of Enzyme Inactivation and the Impact of Light Intensity and Temperature

Photoenzymatic cascades can be used for selective oxygenation of C−H-Bonds under mild conditions circumventing the hydrogen peroxide mediated peroxygenase inactivation via in situ H₂O₂ generation. Here, we report the “on demand” production of hydrogen peroxide via methanol assisted reduction of molecular oxygen using UV...

Disinfection methods for swimming pool water: Byproduct formation and control

This paper presents a comprehensive and critical comparison of 10 disinfection methods of swimming pool water: chlorination, electrochemically generated mixed oxidants (EGMO), ultraviolet (UV) irradiation, UV/chlorine, UV/hydrogen peroxide (H₂O₂), UV/H₂O₂/chlorine, ozone (O₃)/chlorine, O...

Managed aquifer recharge as a barrier for ozone-based advanced oxidation by-products: BrO3- and H2O2

Managed Aquifer Recharge (MAR) is a technology that relies on soil passage - after pond infiltration - for water treatment. MAR is a proven technology for the removal of pathogenic micro-organisms, turbidity and a selection of specific organic micro-pollutions (OMPs). Nevertheless, removal of the wide variety of OMPs found in surface waters...

Efficacy of Plasma Activation on Bleaching

This in vitro study aimed to evaluate the bleaching efficacy and color stability of nonthermal atmospheric pressure plasma (NAPP)-activated 40% hydrogen peroxide (HP) and deionized water (DW). Methods: Two hundred-forty bovine enamel−dentin samples were stained with a coffee solution before bleaching. Samples were randomly divided into 12 (n =...

Multienzymatic in situ hydrogen peroxide generation cascade for peroxygenase-catalysed oxyfunctionalisation reactions

There is an increasing interest in the application of peroxygenases in biocatalysis, because of their ability to catalyse the oxyfunctionalisation reaction in a stereoselective fashion and with high catalytic efficiencies, while using hydrogen peroxide or organic peroxides as oxidant. However, enzymes belonging to this class exhibit a very...

Effect of residual H2O2 from advanced oxidation processes on subsequent biological water treatmen: A laboratory batch study

H2O2 residuals from advanced oxidation processes (AOPs) may have critical impacts on the microbial ecology and performance of subsequent biological treatment processes, but little is known. The objective of this study was to evaluate how H2O2 residuals influence sand systems with an emphasis on dissolved organic carbon (DOC) removal, microbial...

Light-driven enzymatic decarboxylation

Oxidoreductases belong to the most-applied industrial enzymes. Nevertheless, they need external electrons whose supply is often costly and challenging. Recycling of the electron donors NADH or NADPH requires the use of additional enzymes and sacrificial substrates. Interestingly, several oxidoreductases accept hydrogen peroxide as electron...

Electrochemical determination of hydrogen peroxide using Rhodobacter capsulatus cytochrome c peroxidase at a gold electrode

We describe the redox behaviour of horse heart cytochrome c (HHC) and Rhodobacter capsulatus cytochrome c peroxidase (RcCCP) at a gold electrode modified with 4,4?-bipyridyl. RcCCP shows no additional oxidation or reduction peaks compared to the electrochemistry of only HHC, which indicates that it most likely binds to HHC and results in a...