PURPOSE This in vitro experiment studied the effects of sodium bicarbonate and hydrogen peroxide on the cariogenic bacteria Streptococcus mutans through analysis with a spectrophotometer. METHODS The growth of S. mutans was analyzed using seven different environments. Twelve wells in each of the seven rows of a multi-well plate were used to incubate the test materials. In combinations of 10 m...

We employ reversed-phase ion-pair high-performance liquid chromatography to quantitatively characterize the oxidation kinetics of thiourea oxidation by hydrogen peroxide. The HPLC technique makes it possible to monitor the concentrations of a variety of sulfur-containing species with different oxidation states and to elucidate the relative phase relations among them. The experimental results ar...

Bioassay-guided fractionation of the extract of Jamaican marine sponge Plakortis sp. followed by preparative TLC and HPLC yielded several known methyl ester cyclic peroxides (1a, 2a, 3a, 4, 5), known plakortides (6,7), known bicyclic lactone (8) and new cyclic peroxide acids (1b, 2b, 3b). The chemical structures were elucidated by extensive interpretation of their spectroscopic data. These natu...

Pectins isolated from sugar beet pulp by autoclaving contained significant amounts of ferulates, 8.8% of which were ferulate dehydrodimers. The 8-8 and 8-0-4 dehydrodimers were predominant. Oxidative cross-linking with hydrogen peroxide/peroxidase lowered the amount of ferulic acid by 78%, while an increase in ferulate dehydrodimers by a factor of 4.9 was observed. The highest increase was seen...

The activity of H(2)O(2) against the resistant cyst stage of the pathogenic free-living amoeba Acanthamoeba was enhanced by the addition of KI and either horseradish peroxidase or soybean peroxidase or, to a lesser degree, lactoperoxidase. This resulted in an increase in the cysticidal activity of 3% (wt/vol) H(2)O(2), and there was >3-log killing in 2 h, compared with the 6 h required for comp...

introduction: nowadays, spermatogonial stem cells (sscs) cultivation has been used by many researchers as an effective tool for infertility treatments. oxidative conditions can be effective on cell proliferation and differentiation of these cells. so, the aim of this study was to establish oxidative stress model for antioxidant activity of some drugs investigation during sscs in vitro culture. ...

introduction: the prevalence of chronic diseases increases with age. increased production of reactive oxygen species involves in the pathogenesis of cardiovascular diseases such as coronary atherosclerosis, hypertension, diabetic vascular complications, and heart failure. the present study aimed to explore the effects of resistance training on plasma hydrogen peroxide (h2o2) level of ageing wom...

leaching of molybdenite concentrate with hydrogen peroxide in sulfuric acid solution was investigated to determine the effects of reaction time, reaction temperature, h2o2 concentration, h2so4 concentration, pulp density and rotation speed on molybdenum extraction and molybdenite dissolution kinetics, using the taguchi method. from analysis of variance (anova) for molybdenum extraction, the mos...

BACKGROUND Microbial corneal infection is the most serious complication of contact lens wear. Contact lens cases are a recognised potential source of pathogens associated with corneal ulcers. METHODS This survey established the incidence of protozoal, bacterial, and fungal contact lens case contamination in 101 asymptomatic daily wear cosmetic contact lens wearers from a domiciliary contact l...

The vanadate anion in the presence of pyrazine-2-carboxylic acid (PCA) was found to effectively catalyze the oxidation of isopropanol to acetone with hydrogen peroxide. The electronic spectra of solutions and the kinetics of oxidation were studied. The conclusion was drawn that the rate-determining stage of the reaction was the decomposition of the vanadium(V) diperoxo complex with PCA, and the...