scholarly journals A Novel Technique Using Advanced Oxidation Process (UV-C/H2O2) Combined with Micro-Nano Bubbles on Decontamination, Seed Viability, and Enhancing Phytonutrients of Roselle Microgreens

Horticulturae ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 53
Author(s):  
Surisa Phornvillay ◽  
Suwanan Yodsarn ◽  
Jiraporn Oonsrithong ◽  
Varit Srilaong ◽  
Nutthachai Pongprasert
Keyword(s):  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Microbiological Quality ◽  
Advanced Oxidation ◽  
Ascorbic Acid Content ◽  
Biochemical Properties ◽  
Total Phenolic ◽  
E Coli ◽  
Hydroxy Radicals ◽  
Uv C

Microbial contamination commonly occurs in microgreens due to contaminated seeds. This study investigated the decontamination effects of water wash (control), 5% hydrogen peroxide (H2O2), UV-C (36 watts), advanced oxidation process (AOP; H2O2 + UV-C), and improved AOP by combination with microbubbles (MBs; H2O2 + MBs and H2O2 + UV-C + MBs) on microbial loads, seeds’ viability, and physio-biochemical properties of microgreens from corresponding roselle seeds. Results showed that H2O2 and AOP, with and without MBs, significantly reduced total aerobic bacteria, coliforms, Escherichia coli (E. coli), and molds and yeast log count in seeds as compared to the control. Improved AOP treatment of H2O2 + UV-C + MBs significantly augmented antimicrobial activity against total bacteria and E. coli (not detected,) as compared to control and other treatments due to the formation of the highest hydroxy radicals (5.25 × 10−13 M). Additionally, H2O2 and combined treatments promoted seed germination, improved microbiological quality, total phenolic, flavonoids, and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) activity of the grown microgreens. Ascorbic acid content was induced only in microgreens developed from H2O2-treated seeds. Single UV-C treatment was ineffective to inactivate the detected microorganism population in seeds. These findings demonstrated that improved AOP treatment (H2O2 + UV-C + MBs) could potentially be used as a new disinfection technology for seed treatment in microgreens production.

scholarly journals Decontamination of N95 and surgical masks using a treatment based on a continuous gas phase-Advanced Oxidation Process

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248487
Author(s):  
Mahdiyeh Hasani ◽  
Tracey Campbell ◽  
Fan Wu ◽  
Keith Warriner
Keyword(s):  
Hydrogen Peroxide ◽  
Gas Phase ◽  
Hydroxyl Radicals ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Continuous Process ◽  
Oxidative Polymerization ◽  
Advanced Oxidation ◽  
Surgical Masks ◽  
Uv C

A gas-phase Advanced Oxidation Process (gAOP) was evaluated for decontaminating N95 and surgical masks. The continuous process was based on the generation of hydroxyl-radicals via the UV-C (254 nm) photo-degradation of hydrogen peroxide and ozone. The decontamination efficacy of the gAOP was dependent on the orientation of the N95 mask passing through the gAOP unit with those positioned horizontally enabling greater exposure to hydroxyl-radicals compared to when arranged vertically. The lethality of gAOP was independent of the applied hydrogen peroxide concentration (2–6% v/v) but was significantly (P<0.05) higher when H2O2 was introduced into the unit at 40 ml/min compared to 20 ml/min. A suitable treatment for N95 masks was identified as 3% v/v hydrogen peroxide delivered into the gAOP reactor at 40 ml/min with continuous introduction of ozone gas and a UV-C dose of 113 mJ/cm2 (30 s processing time). The treatment supported >6 log CFU decrease in Geobacillus stearothermophilus endospores, > 8 log reduction of human coronavirus 229E, and no detection of Escherichia coli K12 on the interior and exterior of masks. There was no negative effect on the N95 mask fitting or particulate efficacy after 20 passes through the gAOP system. No visual changes or hydrogen peroxide residues were detected (<1 ppm) in gAOP treated masks. The optimized gAOP treatment could also support >6 log CFU reduction of endospores inoculated on the interior or exterior of surgical masks. G. stearothermophilus Apex spore strips could be applied as a biological indicator to verify the performance of gAOP treatment. Also, a chemical indicator based on the oxidative polymerization of pyrrole was found suitable for reporting the generation of hydroxyl-radicals. In conclusion, gAOP is a verifiable treatment that can be applied to decontaminate N95 and surgical masks without any negative effects on functionality.

scholarly journals Degradation rates of benzotriazoles and benzothiazoles under UV-C irradiation and the advanced oxidation process UV/H2O2

2015 ◽  
Vol 74 ◽  
pp. 143-154 ◽  
Author(s):  
Sabrina Bahnmüller ◽  
Clara H. Loi ◽  
Kathryn L. Linge ◽  
Urs von Gunten ◽  
Silvio Canonica
Keyword(s):  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Advanced Oxidation ◽  
Degradation Rates ◽  
Uv C

scholarly journals ESTUDIO DE LA DECOLORACIÓN DEL COLORANTE SUNFIX YELLOW S4GL EMPLEANDO EL PROCESO DE OXIDACIÓN AVANZADA H2O2/UV

2018 ◽  
Vol 27 (1) ◽  
pp. 67
Author(s):  
Aldeir Pinedo ◽  
Fernando Anaya
Keyword(s):  
Hydrogen Peroxide ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Advanced Oxidation ◽  
Reactive Dye ◽  
Order Kinetic ◽  
Initial Concentration ◽  
Initial Ph ◽  
Order Kinetic Model ◽  
Uv C

Se ha realizado el estudio cinético de la decoloración del colorante reactivo Sunfix Yellow S4GL (RAS) empleando una disolución de 20 ppm del colorante mediante el proceso de oxidación avanzada (POA) H2O2/UV. Para ello se evaluó el efecto de la concentración inicial del peróxido de hidrógeno, el pH inicial de la solución, la concentración del colorante y la intensidad de la radiación UV‐C sobre la decoloración con el fin de optimizarlos. Los valores óptimos son los siguientes: concentración inicial de H2O2 a 3.8 x 10‐2 mol/L, pH3, concentración inicial del colorante a 20mg/L, potencia de radiación 3 lámparas con potencia de 15W de radiación UV‐C cada una. El estudio cinético de la decoloración sigue un modelo cinético de pseudo primer orden. Bajo condiciones óptimas se obtuvo un porcentaje de decoloración del 100% luego de una hora de tratamiento. Palabras clave.- decoloración, proceso de oxidación avanzada (POA), peróxido de hidrógeno, radiación UV‐C em> ABSTRACT A study of the kinetics of discoloration of a 20 ppm solution of Sunfix Yellow S4GL (RAS) reactive dye has been carried out using the H2O2/UV advanced oxidation process (AOP). To optimize the process, the effects on the discoloration of the initial concentration of hydrogen peroxide, the initial pH of the solution, the dye concentration and the intensity of the UV‐ C radiation were evaluated. The optimum values were the following: initial concentration of H2O2 a 3.8 x 10‐2 mol/L, pH3; initial dye concentration: 20 mg/L; UV radiation: 3 bulbs with 15 W of UV‐C power each. The discoloration reaction followed a pseudo first order kinetic model. Under optimum conditions, a one hour treatment yielded 100% discoloration. Keywords.- discoloration, advanced oxidation process (AOP), hydrogen peroxide, UV‐C radiation.

Influence of mineral water constituents, organic matter and water matrices on the performance of the H2O2/IO4−-advanced oxidation process

2019 ◽  
Vol 5 (11) ◽  
pp. 1985-1992 ◽  
Author(s):  
Nor Elhouda Chadi ◽  
Slimane Merouani ◽  
Oualid Hamdaoui ◽  
Mohammed Bouhelassa ◽  
Muthupandian Ashokkumar
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Mineral Water ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Advanced Oxidation ◽  
Water Constituents

We have recently reported that the reaction of H2O2/IO4− could be a new advanced oxidation process for water treatment [N. E. Chadi, S. Merouani, O. Hamdaoui, M. Bouhelassa and M. Ashokkumar, Environ. Sci.: Water Res. Technol., 2019, 5, 1113–1123].

scholarly journals Fate of Diclofenac and Its Transformation and Inorganic By-Products in Different Water Matrices during Electrochemical Advanced Oxidation Process Using a Boron-Doped Diamond Electrode

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1686 ◽  
Author(s):  
Carolin Heim ◽  
Mohamad Rajab ◽  
Giorgia Greco ◽  
Sylvia Grosse ◽  
Jörg E. Drewes ◽  
...  
Keyword(s):  
Current Density ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Early Stage ◽  
Advanced Oxidation ◽  
Target Compound ◽  
Duration Of Treatment ◽  
Boron Doped Diamond ◽  
Boron Doped ◽  
By Products

The focus of this study was to investigate the efficacy of applying boron-doped diamond (BDD) electrodes in an electrochemical advanced oxidation process, for the removal of the target compound diclofenac (DCF) in different water matrices. The reduction of DCF, and at the same time the formation of transformation products (TPs) and inorganic by-products, was investigated as a function of electrode settings and the duration of treatment. Kinetic assessments of DCF and possible TPs derived from data from the literature were performed, based on a serial chromatographic separation with reversed-phase liquid chromatographyfollowed by hydophilic interaction liquid chromatography (RPLC-HILIC system) coupled to ESI-TOF mass spectrometry. The application of the BDD electrode resulted in the complete removal of DCF in deionized water, drinking water and wastewater effluents spiked with DCF. As a function of the applied current density, a variety of TPs appeared, including early stage products, structures after ring opening and highly oxidized small molecules. Both the complexity of the water matrix and the electrode settings had a noticeable influence on the treatment process’s efficacy. In order to achieve effective removal of the target compound under economic conditions, and at the same time minimize by-product formation, it is recommended to operate the electrode at a moderate current density and reduce the extent of the treatment.

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