ascorbic-acid and sodium-thiosulfate

To prevent the reactions of disinfection byproducts (DBPs) or natural organic matters with residual chlorine in drinking water in the course of the water store, residual chlorine is quenched by chlorine quenchers, while some chlorine quenchers may result in dechlorination of DBPs. Phenolic compounds are a group of highly toxic DBPs compared to regulated aliphatic DBPs (trihalomethanes (THMs) and haloacetic acids (HAAs)), which might be a great threat to drinking water safety. Nevertheless, impact of popular chlorine quenchers on phenolic DBPs is less understanding. In this study, the influences of ammonium chloride, ascorbic acid, sodium thiosulfate, and sodium sulfite on phenolic DBPs are assessed. Total concentration of 19 phenolic DBPs in drinking water from 7 Chinese cities was 145-1821 ng/L, suggesting a widely occurrence of these pollutants. Four assessed chlorine quenchers have not impacts on mass spectra of studied phenolic DBPs. Additionally, when the storage time ≤24 h, recoveries of 19 phenolic DBPs using four assessed chlorine quenchers are within the accept levels (70-130 %). However, when the storage time increased to 168 h, ascorbic acid and sodium thiosulfate satisfied the recovery requirement of phenolic DBPs during the sample analysis, and ammonium chloride and sodium sulfite showed a unacceptable impact on bromo-chloro-phenols. In general, ascorbic acid and sodium thiosulfate are recommended to be the ideal chlorine quenchers of phenolic DBPs. Mechanism study indicated that sodium sulfite induced the dechlorination of 2-chloro-4-bromophenol via nucleophilic reaction. This study is the first attempt to provide the impact of chlorine quenchers on phenolic DBPs and corresponding reaction mechanism.

Topics: Ammonium Chloride; Ascorbic Acid; Chlorides; Chlorine; Disinfectants; Disinfection; Drinking Water; Halogenation; Trihalomethanes; Water Pollutants, Chemical; Water Purification

A major barrier to the commercialization of somatic embryogenesis technology in loblolly pine (Pinus taeda L.) is recalcitrance of some high-value crosses to initiate embryogenic tissue (ET) and continue early-stage somatic embryo growth. Developing initiation and multiplication media that resemble the seed environment has been shown to decrease this recalcitrance. Glutathione (GSH), glutathione disulfide (GSSG), ascorbic acid and dehydroascorbate analyses were performed weekly throughout the sequence of seed development for female gametophyte and zygotic embryo tissues to determine physiological concentrations. Major differences in stage-specific oxidation-reduction (redox) agents were observed. A simple bioassay was used to evaluate potential growth-promotion of natural and inorganic redox agents added to early-stage somatic embryo growth medium. Compounds showing statistically significant increases in early-stage embryo growth were then tested for the ability to increase initiation of loblolly pine. Low-cost reducing agents sodium dithionite and sodium thiosulfate increased ET initiation for loblolly pine and Douglas fir (Mirb) Franco. Germination medium supplementation with GSSG increased somatic embryo germination. Early-stage somatic embryos grown on medium with or without sodium thiosulfate did not differ in GSH or GSSG content, suggesting that sodium thiosulfate-mediated growth stimulation does not involve GSH or GSSG. We have developed information demonstrating that alteration of the redox environment in vitro can improve ET initiation, early-stage embryo development and somatic embryo germination in loblolly pine.

Topics: Ascorbic Acid; Germination; Glutathione; Glutathione Disulfide; Ovule; Oxidation-Reduction; Pinus; Plant Somatic Embryogenesis Techniques; Pseudotsuga; Seeds; Thiosulfates

The inhibitory effect of commonly known oxidants and their quenching agents was investigated by employing a battery of toxicity tests. Hydrogen peroxide toxicity could be effectively eliminated by the enzyme catalase, whereas sodium thiosulfate and ascorbic acid were recommended as suitable quenching agents for the removal of the oxidants persulfate and peroxymonosulfate in the Vibrio fischeri bioassays. None of the studied quenching agents was found to be suitable for persulfate and peroxymonosulfate in the Daphnia magna bioassays since high inhibitory effects were obtained for both oxidants. In the case of Pseudokirchneriella subcapitata, manganese dioxide powder should be used as an alternative quenching agent to catalase, since this enzyme exhibited a highly toxic effect towards these microalgae. Sodium sulfite, which is extensively used as a quenching agent, was not appropriate for quenching peroxymonosulfate in all studied bioassays.

Topics: Aliivibrio fischeri; Animals; Antioxidants; Ascorbic Acid; Biological Assay; Catalase; Chlorophyta; Daphnia; Hydrogen Peroxide; Luminescence; Manganese Compounds; Oxidants; Oxidation-Reduction; Oxides; Peroxides; Potassium Compounds; Sulfates; Sulfites; Thiosulfates; Waste Disposal, Fluid; Water Purification

A practical, sensitive and environment-benign protocol for the detection of DNA on polyacrylamide gels was described. In this method, the most commonly used formaldehyde-based developer in DNA silver stain, which poses potential hazards to the health of operators, is firstly replaced by vitamin C (Vc) in sodium thiosulfate solution. This allows user-friendly and efficient visualization of DNA that takes about 20 min to complete all the procedures, and provides comparable sensitivity (8 pg of single band) to the most sensitive formaldehyde-based silver staining method developed before.

Topics: Ascorbic Acid; Conservation of Natural Resources; DNA; Dose-Response Relationship, Drug; Electrophoresis, Agar Gel; Formaldehyde; Humans; Occupational Health; Reproducibility of Results; Silver; Silver Staining; Thiosulfates; Time Factors

A simple, isocratic, and stability-indicating high-performance liquid chromatography (HPLC) method has been developed for the rapid determination of thiamine (VB(1)), niacinamide (VB(3)), pyridoxine (VB(6)), ascorbic acid (VC), pantothenic acid (VB(5)), riboflavin (VB(2)) and folic acid (VB(9)) in Vitamins with Minerals Tablets (VMT). An Alltima C(18) column (250 mm × 4.6 mm i.d., 5 μm) was used for the separation at ambient temperature, with 50mM ammonium dihydrogen phosphate (adjusting with phosphoric acid to pH 3.0) and acetonitrile as the mobile phase at the flow rate of 0.5 ml min(-1). VB(1), VB(3), VB(6), VC and VB(5) were extracted with a solution containing 0.05% phosphoric acid (v/v) and 0.3% sodium thiosulfate (w/v), and were then simultaneously analyzed by using the mobile phase of phosphate buffer-acetonitrile (95:5, v/v), while VB(2) and VB(9) were extracted with a solution containing 0.5% ammonium hydroxide solution (v/v), and were then simultaneously analyzed by using the mobile phase of phosphate buffer-acetonitrile (85:15, v/v). The detection wavelengths were 275 nm for VB(1), VB(3), VB(6), VC, 210 nm for VB(5), and 282 nm for VB(2) and VB(9). The method showed good system suitability, sensitivity, linearity, specificity, precision, stability and accuracy. All the seven water-soluble vitamins were well separated from other ingredients and degradation products. Method comparison indicated good concordance between the developed method and the USP method. The developed method was reliable and convenient for the rapid determination of VB(1), VB(3), VB(6), VC, VB(5), VB(2) and VB(9) in VMT.

Topics: Acetonitriles; Ammonium Hydroxide; Ascorbic Acid; Buffers; Calibration; Chromatography, High Pressure Liquid; Drug Combinations; Drug Stability; Folic Acid; Hydrogen-Ion Concentration; Hydroxides; Limit of Detection; Niacinamide; Pantothenic Acid; Phosphates; Phosphoric Acids; Pyridoxine; Reference Standards; Reproducibility of Results; Riboflavin; Sensitivity and Specificity; Solubility; Tablets; Temperature; Thiamine; Thiosulfates; Time Factors; Vitamins

Topics: Adult; Ascorbic Acid; Child; Drug Therapy, Combination; Female; Follow-Up Studies; Humans; Interferon Type I; Male; Prodigiozan; Psoriasis; Thiosulfates

The influences of methylene blue (MB), thionine, ascorbic acid (ASA), sodium thiosulfate (STS), N-(2-mercaptopropionyl)-glycine (MPG) and reduced glutathione (GSH) on methemoglobin-(MHb)-emia and sulf-hemoglobin (SHb)-emia induced by 4-chloroaniline (4-Cl-A) i.p. were studied. Preventive or therapeutic effect on MHb-emia and preventive effect on SHb-emia in mice: MHb formation was inhibited by MB i.p. whether it was administered simultaneously with or after 4-Cl-A, but SHb formation was increased. Similar effects were seen with thionine. Both compounds proved to have MHb and SHb forming activities. STS or MPG, if administered i.p. simultaneously with 4-Cl-A, inhibited formation of MHb, but exerted no effect on delayed SHb formation. However, if administered i.p. or i.v. 120 minutes after 4-Cl-A when the peak of MHb formation had passed, there was a preventive effect on delayed SHb formation. GSH inhibited MHb formation and prevented SHb formation only when it was administered i.v. 120 minutes after 4-Cl-A. ASA did not inhibit MHb formation when it was administered either i.p. or i.v., but showed a preventive effect on SHb formation, if administered 120 minutes after 4-Cl-A. Combined i.v. administration of the corresponding doses to the clinical ones of MB and ASA 120 minutes after 4-Cl-A showed a therapeutic effect on MHb-emia and a preventive effect on SHb-emia. However, at higher dose levels, MB masked the preventive effect of ASA on SHb-emia. Therapeutic effect on SHb-emia in mice and rats: None of MB, STS, GSH and ASA proved to have any therapeutic effects for established SHb-emia. On the basis of these results, significance of clinical usage of drugs in the treatment of chemically induced MHb-emia and SHb-emia is discussed.

Topics: Aniline Compounds; Animals; Ascorbic Acid; Ergothioneine; Glutathione; Male; Methemoglobinemia; Methylene Blue; Mice; Rats; Sulfhemoglobinemia; Thiosulfates; Tiopronin