Efficacy Of Hydrogen Peroxide Research Articles

Does repeated exposure to hydrogen peroxide induce Candida auris resistance?

BackgroundTo minimize environmental colonization by microorganisms that may persist and thrive in healthcare settings, thus reducing healthcare-associated infections (HAIs), new insights over already known biocides are certainly of relevance. Although the efficacy of hydrogen peroxide (H2O2) against the emergent yeast Candida auris is moderately documented, concerns over the potential induction of resistance after repeated exposure do persist. The main objective of the present study was to evaluate the hypothetical induction of Candida auris resistance following 30 days of consecutive exposure to lethal and sublethal concentrations of H2O2. Furthermore, the authors aimed to elucidate about the rank of efficacy of H2O2 against C. auris comparing to other Candida species and whether different strains of C. auris may display different susceptibilities to H2O2.MethodsDuring the induction of resistance assays, both type strains and clinical isolates of Candida auris, Candida albicans and Candida parapsilosis were exposed repeatedly to defined concentrations of H2O2, for 30 days.ResultsAfter that period, no significant differences were found when comparing the minimal inhibitory concentration values of H2O2 in case of the induced strains versus each respective positive control. Moreover, H2O2 displayed similar effectiveness against all the tested Candida species and no differences were demonstrated among the distinct strains of C. auris.ConclusionsThe adoption of H2O2 solutions in routine protocols in order to promote disinfection standards against Candida auris, improving patient safety and reducing healthcare costs, is certainly welcomed.

Inhibition of Phytophthora cinnamomi mycelial growth with stabilised hydrogen peroxide

The efficacy of hydrogen peroxide (H2O2) was evaluated for the inhibition of mycelial growth of Phytophthora cinnamomi in vitro. Phytophthora cinnamomi infects many crops globally causing root, collar and crown rot, resulting in significant economic losses for producers. Two 30% (w/v) H2O2 products, each stabilised with a different concentration of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP) (3% versus 0.003% w/v) were compared to determine the most efficacious H2O2 concentration as well as potential interactive effects of the stabilising compound. Inhibition of P. cinnamomi growth was evaluated by amending potato dextrose agar media (PDA) with a range of concentrations of the test solutions. The biocidal activity of H2O2 was enhanced by a higher concentration of HEDP. Concentrations from 6.25 mL/L of the H2O2 product with 3% HEDP provided 100% inhibition of mycelial growth in vitro. Neither the product with 0.003% HEDP, nor HEDP stabiliser without H2O2, achieved comparable inhibition. Our results highlight an opportunity to expand the use of stabilised H2O2 products developed for cleaning of drip irrigation emitters to include the control of Phytophthora spp. and potentially other waterborne plant pathogens.

Resistance enhancement of faba bean plants to rust disease by some compounds and plant extracts

The current study aimed to evaulate the efficacy of hydrogen peroxide, ammonium chloride and sulfur nanoparticles, aqueous plant extracts of pelargonium, thyme and carnation and Tilt 25% fungicide for controlling fabae bean rust disease and investigate the induction of resistance of faba bean plants against rust disease. All above treatments were tested on urediniospores germination of Uromyces viciae-fabae in vitro. Among the treatments used, hydrogen peroxide at 50 mM and pelargonium extract at 20% were the most effective, which decreased of urediniospores germination 34.2 and 36.75%, respectively, than the other treatments. Spraying of infected faba bean plants Spanish cultivar with all tested treatments was effective in reducing disease severity of rust disease under greenhouse and field conditions. The highest reduction in disease severity was observed in case of Tilt 25% fungicide treatment, followed by hydrogen peroxide. Furthermore, all treatments significantly increased total phenol content and enzymes activity in treated plants compared to untreated plants. Morevere, the application of these treatments enhanced significantly all studied agronomic characters, i.e., plant height (cm), number of pods per plant and weight of 100 seeds (gm). The study indicated that these treatments can be useful for the protection of faba bean plants from rust disease, especially in clean farming.

The role of hydrogen peroxide in hip arthroplasty: A narrative review.

Hydrogen peroxide has become more commonly used in hip arthroplasties due to high risk of periprosthetic infections. Its purported roles include irrigation, haemostasis, reduction of aseptic loosening and attachment of antibiotics. However, current literature does not provide conclusive evidence on the efficacy of hydrogen peroxide in preventing aseptic loosening, with some controversy around whether it in fact contributes to aseptic loosening. The complications of hydrogen peroxide across medicine are well distinguished; however, the risks within orthopaedic surgery and hip arthroplasties are not well known. Beyond cytotoxicity, the most dangerous reported risk associated with hydrogen peroxide in hip arthroplasties was an oxygen embolism in an unvented femoral canal and acrylic bone cement, consequentially leading to cardiac arrest. However, it may be inappropriate to solely attribute the oxygen embolism to the use of hydrogen peroxide and thus if used appropriately, hydrogen peroxide may have a justifiable role in hip arthroplasty surgery. In this narrative review, we present the current uses of hydrogen peroxide while evaluating its associated risks. We have summarised the key indications and aggregated recommendations to provide guidelines for the use of hydrogen peroxide in hip arthroplasty.

Histopathological changes of neuronal tissue following the use of hydrogen peroxide in neurosurgical procedures.

Background: Hydrogen peroxide (HP) is routinely used in neurosurgical procedures to achieve surgical hemostasis. However, its safety profile is still debatable with various reports depicting range of adverse effects on neuronal tissue. The objective of this paper is to evaluate the safety and efficacy of HP as a hemostatic agent in normal neuronal tissue during neurosurgical procedures conducted on rats.Methods: One hundred rats were divided into three groups. The first and third group underwent cortical irrigation with HP and the second group underwent spinal irrigation with HP. All groups were irrigated with different concentrations of HP (1%, 3%, or 6%) for 3 min and tissue biopsies were obtained immediately afterwards (Groups A and B) or 1 week after HP irrigation (Group C). Study specimens were examined histologically and compared to control tissue.Results: All rats showed normal behavioral, functional, and motor neurological activity following the procedures. Histopathologically, dark neurons were observed in all HP exposed tissue. The cytoplasm revealed condensed and dark Nissl substance and the neurites and axons exhibited a corkscrew morphology. No ischemic changes or inflammatory infiltrates were detected. The majority of dark neurons were observed at the periphery of tissue fragments. These findings were present and consistent in both the short- and long-term groups.Conclusion: HP irrigation showed no significant short- or long-term clinical and histopathological changes in comparison to normal saline when used on rats’ neuronal tissue. This may confirm the safety of intraoperative HP usage as hemostatic agent during neurosurgical procedures.

188. The safety and efficacy of hydrogen peroxide in controlling blood loss and surgical site infection after multi-segmental lumbar spine surgery: a retrospective, case-controlled study of 2,626 patients

BACKGROUND CONTEXT Multiple-level lumbar fusion surgery is associated with prolonged duration of surgery and significant blood loss, which are deemed significant risk factors for postoperative SSI. Controlling the blood loss and improving local resistance to pathogens is extremely valuable to reduce perioperative complications, including SSI, and speed up recovery after surgery. Concerns regarding the safety profile of TXA, whether it increases the incidence of thromboembolic events, such as deep vein thrombosis (DVT), pulmonary embolism (PE), and myocardial infarctions (MI), have been raised frequently, especially for the patients who have accompanying cardiovascular and cerebrovascular diseases, which are relatively common in patients with degenerative spinal disease. Additionally, it is strongly debated whether the usage of vancomycin powder can induce culture-negative seroma formation and affect bone healing. Hydrogen peroxide (H2O2) is an inexpensive and readily available option whose hemostatic and antiseptic properties have been separately confirmed in several previous studies. However, whether H2O2 can integrate the advantages of vancomycin and TXA in controlling blood loss and postoperative SSI simultaneously after lumbar spine surgery has not been explored, neither have its complications. PURPOSE This study aimed to explore the safety and efficacy of H2O2 in controlling blood loss and SSI after multi-segmental lumbar spine surgery. STUDY DESIGN/SETTING Retrospective case-control study. PATIENT SAMPLE A total of 2,626 patients who underwent multi-segmental lumbar spinal surgery between January 2015 and January 2018 were included in this study. According to whether H2O2 irrigation was applied, they were divided into control group (1,345 patients) and experimental group (1,281 patients).The inclusion criteria were: (1) patients were diagnosed with thoracic and/or lumbar degenerative diseases, such as spinal canal stenosis, disc herniation, spondylolisthesis, and/or degenerative scoliosis; (2) patients treated with multilevel (operated level > 2) posterior lumbar interbody fusion (PLIF) with or without posterolateral fusion. The exclusion criteria were: patients diagnosed with spinal fracture-dislocation, infection, tuberculosis, tumor, congenital spinal deformity or received revision surgery; patients with a coagulation or hemoglobin dysfunction before surgery; dura tear accompanied by cerebrospinal fluid leakage detected intraoperatively; the perioperative use of hemostatic agents such as TXA or treatment with antifibrinolytic drugs. OUTCOME MEASURES The primary outcome evaluated was the incidence of SSI. The definition of SSI including superficial and deep infection after lumbar spinal surgery was derived from the guidelines published by the U.S. Centers for Disease Control and Prevention. Superficial infection is defined as occurring within 30 days after surgery, involving only the incision skin and subcutaneous tissue. Deep infection is defined as occurring within 1 year after operation, characterized by superficial infection, the involving fascia and myometrium. Besides the demographic parameters, the laboratory examination results and surgery related information such as operative time, numbers of operated levels, intraoperative blood loss, postoperative drainage, postoperative SSI and extubation time were recorded. The perioperative complications including pneumocephalus, symptomatic DVT, PE and MI were included in the evaluation. METHODS A standard posterior midline incision and exposure was applied; and irrigation with 1 L of saline was performed before skin closure in all patients. For the experimental group, the incision was soaked with 50 mL of 3% H2O2 solution for 30 s before the saline irrigation. RESULTS No significant differences were seen regarding demographic parameters, laboratory examination results, comorbidities and surgical related information. The extubation time and postoperative drain collection were lower in the experimental group (3.6±0.5 days vs 4.1±0.6, p=0.402; 251.8±67.5 vs 291.8±71.3, p=0.013). In the control group, the rate of SSI was 2.4% (32/1345), including 17 superficial wound infections and 15 deep wound infections. In the experimental group, the SSI rate was 1.4% (18/1281), including 15 patients with superficial wound infection and three with deep wound infection. Staphylococcus aureus was the most common organism, especially in the experimental group (66.7% vs 50%). There was no significant difference between both groups in the perioperative complications such as hematencephalon, DVT, PE and MI (p>0.05, respectively). Pneumocephalus was not observed in either group. CONCLUSIONS The application of H2O2 in PLIF does not increase the perioperative complications such as hematencephalon, DVT, PE, MI, and especially pneumocephalus; it also reducing the blood loss and SSI after surgery, which is quite promising for patients with a high risk of thromboembolic events and beneficial for controlling the increasing number of vancomycin-resistant bacteria. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

The Efficacy of Hydrogen Peroxide in Mitigating Cyanobacterial Blooms and Altering Microbial Communities across Four Lakes in NY, USA.

Hydrogen peroxide (H2O2) has been proposed as an agent to mitigate toxic cyanobacterial blooms due to the heightened sensitivity of cyanobacteria to reactive oxygen species relative to eukaryotic organisms. Here, experiments were conducted using water from four diverse, eutrophic lake ecosystems to study the effects of H2O2 on cyanobacteria and non-target members of the microbial community. H2O2 was administered at 4 µg L−1 and a combination of fluorometry, microscopy, flow cytometry, and high throughput DNA sequencing were used to quantify the effects on eukaryotic and prokaryotic plankton communities. The addition of H2O2 resulted in a significant reduction in cyanobacteria levels in nearly all experiments (10 of 11), reducing their relative abundance from, on average, 85% to 29% of the total phytoplankton community with Planktothrix being highly sensitive, Microcystis being moderately sensitive, and Cylindrospermopsis being most resistant. Concurrently, eukaryotic algal levels increased in 75% of experiments. The bacterial phyla Actinobacteria, cyanobacteria, Planctomycetes, and Verrucomicrobia were most negatively impacted by H2O2, with Actinobacteria being the most sensitive. The ability of H2O2 to reduce, but not fully eliminate, cyanobacteria from the eutrophic water bodies studied here suggests it may not be an ideal mitigation approach in high biomass ecosystems.

A novel micellar formulation based on natural plant extracts enhances the efficacy of hydrogen peroxide against biofilms of Staphylococcus spp. and Pseudomonas aeruginosa

The antibacterial efficacy of hydrogen peroxide encapsulated in micelles (mH2O2) against biofilms was compared with that of hydrogen peroxide alone and of three commercially available aqueous biocides. The activity of mH2O2 on 24-h biofilms of reference strains of Staphylococcus spp. and Pseudomonas aeruginosa was tested in a static microtiter plate model. The biofilms were incubated with mH2O2 (17% v/v H2O2, 2% lactic acid, 0.3% phytoextract, H2O) and its individual ingredients and compared with three aqueous biocides at different concentrations and times of exposure. After 5-min exposure, 10% mH2O2 (corresponding to 1.7% v/v H2O2) achieved > 8 log10 reductions against all the test strains, while 1.7% H2O2 achieved a maximum of 1.5 log10 reduction. After 5-min exposure, none of the commercially available biocides tested showed themselves to be capable of completely eliminating the test strains embedded in biofilms. Hydrogen peroxide encapsulated in micelles demonstrated enhanced activity against planktonic cells and biofilms of Staphylococcus spp. and P. aeruginosa.

Effect of violet LED light on in-office bleaching protocols: a randomized controlled clinical trial.

ObjectiveThis study evaluated the clinical effect of violet LED light on in-office bleaching used alone or combined with 37% carbamide peroxide (CP) or 35% hydrogen peroxide (HP).MethodologyA total of 100 patients were divided into five groups (n=20): LED, LED/CP, CP, LED/HP and HP. Colorimetric evaluation was performed using a spectrophotometer (ΔE, ΔL, Δa, Δb) and a visual shade guide (ΔSGU). Calcium (Ca)/phosphorous (P) ratio was quantified in the enamel microbiopsies. Measurements were performed at baseline (T 0 ), after bleaching (T B ) and in the 14-day follow-up (T 14 ). At each bleaching session, a visual scale determined the absolute risk (AR) and intensity of tooth sensitivity (TS). Data were evaluated by one-way (ΔE, Δa, ΔL, Δb), two-way repeated measures ANOVA (Ca/P ratio), and Tukey post-hoc tests. ΔSGU and TS were evaluated by Kruskal-Wallis and Mann-Whitney, and AR by Chi-Squared tests (a=5%).ResultsLED produced the lowest ΔE (p<0.05), but LED/HP promoted greater ΔE, ΔSGU and Δb (T 14 ) than HP (p<0.05). No differences were observed in ΔE and ΔSGU for LED/CP and HP groups (p>0.05). ΔL and Δa were not influenced by LED activation. After bleaching, LED/CP exhibited greater Δb than CP (p>0.05), but no differences were found between these groups at T 14 (p>0.05). LED treatment promoted the lowest risk of TS (16%), while HP promoted the highest (94.4%) (p<0.05). No statistical differences of risk of TS were found for CP (44%), LED/CP (61%) and LED/HP (88%) groups (p>0.05). No differences were found in enamel Ca/P ratio among treatments, regardless of evaluation times.ConclusionsViolet LED alone produced the lowest bleaching effect, but enhanced HP bleaching results. Patients treated with LED/CP reached the same efficacy of HP, with reduced risk and intensity of tooth sensitivity and none of the bleaching protocols adversely affected enamel mineral content.

The susceptibility of Proteus mirabilis and Enterococcus faecalis to various antimicrobial agents in polymicrobial biofilms formed using a drip flow reactor

Objectives: Interspecies interactions in poly-species biofilm are substantial. Our aim is to set up dynamic biofilm models ofEnterococcus faecalis and Proteus mirabilis using Drip Flow Biofilm Reactor (DFR) and to evaluate the effect of these dual populationon anti-biofilms of some antimicrobials.Materials and Methods: E.faecalis and P.mirabilis biofilms were formed in a DFR. Influences of the dual interactions on theirsusceptibilities to antimicrobial agents (disinfectants, antibiotics and probiotic strains) were determined.Results: Gluteraldehyde and quaternary ammonium compounds (QAC) effectively killed the cells in both biofilms of E.faecalis andP.mirabilis. However, the efficacy of hydrogen peroxide (H2O2) was dependant on the microbial species present. P. mirabilis was lesssusceptible to the ampicillin and ciprofloxacin in co-culture compared to when cultured alone. Here, the influence of the presenceof E.faecalis on P.mirabilis susceptibility was determined. For high concentrations of ciprofloxacin (1024 and 512 μg/ml), the logreduction in P.mirabilis cells was determined as approximately 4.5 and 3.5 in mono and dual-species biofilms respectively. Comparedto B.lactis, L.acidophilus was found to be more effective both on single and dual species.Conclusion: The effect of antimicrobial agents on microbial cells in a polymicrobial biofilm may depend on the composition of thebiofilm.

Efficacy of Hydrogen Peroxide on Postharvest Quality of White Button Mushroom

Efficacy of Hydrogen Peroxide on Postharvest Quality of White Button Mushroom

Assessment of Chemical Disinfectants Efficacy against Escherichia coli Biofilm Developed on Glass and Wood at Refrigeration and Room Temperatures

Article history: Received on: 04/10/2015 Revised on: 07/11/2015 Accepted on: 26/11/2015 Available online: 27/12/2015 Objectives: The aim of this work was to study the formation of biofilm on glass and wood coupons at refrigeration and room temperatures, different incubation periods and to assess the efficacy of hydrogen peroxide (HP), Para Acetic Acid (PAA), Sodium hypochlorite (SH) and mixture of PAA + SH against the biofilm. Method: 200 μL of 10 8 suspension E. coli ATCC 29922 was inoculated on the coupons inside petri dishes containing 20 ml of tryptic soy broth, incubated at 10 and 27 0 C for 24, 48, 72 and 168 hours. Biofilm developed at each hour above was quantified by bead-vortex followed by agar plating. The action of disinfectants was tested on 168 hours biofilm. The surfaces were exposed to the disinfectants and incubated at 27 °C for 10 minutes, followed by deactivation for 5 minutes. Cells that resisted disinfectants effect were vortexed and enumerated by agar plating. Results: The results showed that E. coli can develop high biofilm on wood apart from glass. After disinfection treatment, HP had the highest efficacy at 27°C followed by PAA then SH, whilst PAA + SH had the least. Conclusion: It can be concluded that HP and PAA can be good disinfectants agents against E. coli biofilm.

Mineralization of Azo Dye Using Combined Photo-Fenton and Photocatalytic Processes under Visible Light

Visible-light-assisted photodegradation of an azo dye, Reactive Red 180 (RR180), in the presence of nitrogen-doped TiO2 (N-TiO2) has been studied. The photodegradation of RR180 is evaluated through decolorization studies and total organic carbon analysis. The efficacy of hydrogen peroxide (H2O2), potassium peroxomonosulfate (oxone or PMS), and potassium peroxodisulfate (PDS) in improving the photodegradation of the dye in the N-TiO2-RR180 system is also examined. The effect of combining photo-Fenton-like reaction with N-TiO2-mediated photodegradation of RR180 under visible light has been investigated. The photoactivity of N-TiO2-RR180-Fe3+/Cu2+-oxidant systems is compared with the individual techniques of photocatalysis and photo-Fenton-like reactions. The coupled system possesses superior photomineralization ability towards the abatement of RR180.

Comparison of total peroxide exposure values and biocidal efficacy of hydrogen peroxide disinfecting systems

Comparison of total peroxide exposure values and biocidal efficacy of hydrogen peroxide disinfecting systems

Effect of temperature and bleaching agent on bleaching of liquid Cheddar whey

The use of whey protein as an ingredient in foods and beverages is increasing, and thus demand for colorless and mild-tasting whey protein is rising. Bleaching is commonly applied to fluid colored cheese whey to decrease color, and different temperatures and bleach concentrations are used. The objectives of this study were to compare the effects of hot and cold bleaching, the point of bleaching (before or after fat separation), and bleaching agent on bleaching efficacy and volatile components of liquid colored and uncolored Cheddar whey. First, Cheddar whey was manufactured, pasteurized, fat-separated, and subjected to one of a number of hot (68°C) or cold (4°C) bleaching applications [hydrogen peroxide (HP) 50 to 500mg/kg; benzoyl peroxide (BP) 25 to 100mg/kg] followed by measurement of residual norbixin and color by reflectance. Bleaching agent concentrations were then selected for the second trial. Liquid colored Cheddar whey was manufactured in triplicate and pasteurized. Part of the whey was collected (no separation, NSE) and the rest was subjected to fat separation (FSE). The NSE and FSE wheys were then subdivided and bleaching treatments (BP 50 or 100mg/kg and HP 250 or 500mg/kg) at 68°C for 30min or 4°C for 16h were applied. Control NSE and FSE with no added bleach were also subjected to each time–temperature combination. Volatile compounds from wheys were evaluated by gas chromatography-mass spectrometry, and norbixin (annatto) was extracted and quantified to compare bleaching efficacy. Proximate analysis, including total solids, protein, and fat contents, was also conducted. Liquid whey subjected to hot bleaching at both concentrations of HP or at 100mg/kg BP had greater lipid oxidation products (aldehydes) compared with unbleached wheys, 50mg/kg BP hot-bleached whey, or cold-bleached wheys. No effect was detected between NSE and FSE liquid Cheddar whey on the relative abundance of volatile lipid oxidation products. Wheys bleached with BP had lower norbixin content compared with wheys bleached with HP. Bleaching efficacy of HP was decreased at 4°C compared with 68°C, whereas that of BP was not affected by temperature. These results suggest that fat separation of liquid Cheddar whey has no effect on bleaching efficacy or lipid oxidation and that hot bleaching may result in increased lipid oxidation in fluid whey.

Efficacy of Hydrogen Peroxide and Dihydroxy Benzol Mixture (Disinfectant) on Toxocara canis Eggs

Efficacy of Hydrogen Peroxide and Dihydroxy Benzol Mixture (Disinfectant) on Toxocara canis Eggs

Acidified nitrite enhances hydrogen peroxide disinfection of Acanthamoeba, bacteria and fungi

In the human innate immune system, stimulated phagocytes release reactive nitrogen intermediates that can react with superoxide to form the powerful oxidant peroxynitrite and other less abundant species. In this study, the efficacy of hydrogen peroxide (H2O2) and acidified nitrite (NaNO2) alone and in combination was compared against a variety of bacteria, fungi and protozoa. Challenge test assays based on the international standard (ISO 14729) were used to determine the antimicrobial activity of H2O2 and acidified NaNO2 at pH 5 alone and in combination against Pseudomonas aeruginosa, Serratia marcescens, Staphylococcus aureus, Mycobacterium aurum, Bacillus subtilis spores, Candida albicans, Fusarium solani conidia and Acanthamoeba polyphaga trophozoites and cysts. When tested alone, both H2O2 (0.4% v/v) and NaNO2 (2 mg/mL, pH 5) produced a >or=4 log reduction in viability after 4 h of exposure for all bacteria and A. polyphaga trophozoites, but not B. subtilis spores, F. solani and A. polyphaga cysts, which gave a <or=1 log kill after 6 h, and M. aurum, which gave a <1 log kill with NaNO2 only. However, the combination of H2O2 and NaNO2 resulted in a >or=4 log kill of all test organisms within 1 h. Addition of NaNO2 also enhanced the antimicrobial efficacy of a H2O2-based contact lens disinfection system. The findings of this study demonstrate that acidified NaNO2 can significantly enhance the antimicrobial activity of H2O2 probably through the generation of peroxynitrite. The addition of acidified nitrite to 3% (v/v) H2O2 solution may represent an improved one-step method for the disinfection of contact lenses, especially against highly resistant cysts of Acanthamoeba spp.

Inactivation of Animal and Human Prions by Hydrogen Peroxide Gas Plasma Sterilization

Prions cause various transmissible spongiform encephalopathies. They are highly resistant to the chemical and physical decontamination and sterilization procedures routinely used in healthcare facilities. The decontamination procedures recommended for the inactivation of prions are often incompatible with the materials used in medical devices. In this study, we evaluated the use of low-temperature hydrogen peroxide gas plasma sterilization systems and other instrument-processing procedures for inactivating human and animal prions. We provide new data concerning the efficacy of hydrogen peroxide against prions from in vitro or in vivo tests, focusing on the following: the efficiency of hydrogen peroxide sterilization and possible interactions with enzymatic or alkaline detergents, differences in the efficiency of this treatment against different prion strains, and the influence of contaminating lipids. We found that gaseous hydrogen peroxide decreased the infectivity of prions and/or the level of the protease-resistant form of the prion protein on different surface materials. However, the efficiency of this treatment depended strongly on the concentration of hydrogen peroxide and the delivery system used in medical devices, because these effects were more pronounced for the new generation of Sterrad technology. The Sterrad NX sterilizer is 100% efficient (0% transmission and no protease-resistant form of the prion protein signal detected on the surface of the material for the mouse-adapted bovine spongiform encephalopathy 6PB1 strain and a variant Creutzfeldt-Jakob disease strain). Thus, gaseous or vaporized hydrogen peroxide efficiently inactivates prions on the surfaces of medical devices.

Use of Hydrogen Peroxide to Improve Golden Shiner Egg Hatchability

AbstractThe efficacy of hydrogen peroxide (H2O2) in controlling fungal infections (saprolegniasis) in the eggs of golden shiner Notemigonus crysoleucas was assessed in two experiments. Golden shiner eggs were exposed in a 15‐min static bath (21°C) to 0, 50, 100, or 200 mg H2O2/L in the first experiment and to 0, 200, 400, and or 800 mg/L in the second experiment. All treatments were based on the amount of active ingredient (30% active ingredient concentration of H2O2) in a single treatment. Three replicates of each concentration were used in each experiment. The objective was to determine the H2O2 concentration that would result in optimum hatching success. The hatching rate significantly increased in each treatment level until 800 mg/L. The mean ± SE percent egg hatchability was 72.3 ± 8.55% and 68.2 ± 5.03% at 400 and 800 mg/L, respectively. Regression analysis revealed the peak treatment level to be between 400 and 800 mg/L.

Occurrence of a Monogenean Gill Parasite Pseudorhabdosynochus epinepheli on Red Spotted Grouper Epinephelus akaara and Its Experimental Treatment by Hydrogen Peroxide Bathing

Since 1997, infection of a monogenean gill parasite Pseudorhabdosynochus epinepheli has been occurring in red spotted grouper Epinephelus akaara at the Kagawa Prefectural Sea-Farming Center, Japan. The efficacy of hydrogen peroxide (H2O2) bathing was examined in vivo. Bathing in a 700 ppm H2O2 solution for 45 min at 10 or 15°C, or for 15 min at 20 or 25°C, with infected fish of 230-2100 g in body weight, resulted in 100% mortality of P. epinepheli on the gills. Mortality occurred in fish (550-1730 g) bathed for 30 min or longer at 25°C, but not in fish bathed for at least 60 min at 10, 15 or 20°C. Results indicate that chemotherapy with H2O2 has a high potential as an effective treatment for P. epinepheli infection in red spotted grouper.