Kinetics of Vitamin E Regeneration by Water-Soluble Antioxidants in Micellar Dispersions

Abstract. Aerosol composition and mixing state near anthropogenic sources can be highly variable and can challenge predictions of cloud condensation nuclei (CCN). The impacts of chemical composition on CCN activation kinetics is also an important, but largely unknown, aspect of cloud droplet formation. Towards this, we present in-situ size-resolved CCN measurements carried out during the 2008 summertime August Mini Intensive Gas and Aerosol Study (AMIGAS) campaign in Atlanta, GA. Aerosol chemical composition was measured by two particle-into-liquid samplers measuring water-soluble inorganic ions and total water-soluble organic carbon. Size-resolved CCN data were collected using the Scanning Mobility CCN Analysis (SMCA) method and were used to obtain characteristic aerosol hygroscopicity distributions, whose breadth reflects the aerosol compositional variability and mixing state. Knowledge of aerosol mixing state is important for accurate predictions of CCN concentrations and that the influence of an externally-mixed, CCN-active aerosol fraction varies with size from 31% for particle diameters less than 40 nm to 93% for accumulation mode aerosol during the day. Assuming size-dependent aerosol mixing state and size-invariant chemical composition decreases the average CCN concentration overprediction (for all but one mixing state and chemical composition scenario considered) from over 190–240% to less than 20%. CCN activity is parameterized using a single hygroscopicity parameter, κ, which averages to 0.16 ± 0.07 for 80 nm particles and exhibits considerable variability (from 0.03 to 0.48) throughout the study period. Particles in the 60–100 nm range exhibited similar hygroscopicity, with a κ range for 60 nm between 0.06–0.076 (mean of 0.18 ± 0.09). Smaller particles (40 nm) had on average greater κ, with a range of 0.20–0.92 (mean of 0.3 ± 0.12). Analysis of the droplet activation kinetics of the aerosol sampled suggests that most of the CCN activate as rapidly as calibration aerosol, suggesting that aerosol composition exhibits a minor (if any) impact on CCN activation kinetics.

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Solution Kinetics of a Water-Soluble Hydrocortisone Prodrug: Hydrocortisone-21-lysinate

Journal of Pharmaceutical Sciences ◽

10.1002/jps.2600740124 ◽

1985 ◽

Vol 74 (1) ◽

pp. 87-89 ◽

Cited By ~ 16

Author(s):

Kevin Johnson ◽

Gordon L. Amidon ◽

Stefano Pogany

Keyword(s):

Water Soluble ◽

Kinetics Of ◽

Solution Kinetics

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Kinetics of the reaction between ascorbate and free radical from vitamin E as studied by ESR steady-state method

Chemistry and Physics of Lipids ◽

10.1016/0009-3084(93)90043-3 ◽

1993 ◽

Vol 65 (2) ◽

pp. 103-112 ◽

Cited By ~ 12

Author(s):

V.A. Roginsky ◽

H.B. Stegmann

Keyword(s):

Steady State ◽

Free Radical ◽

Vitamin E ◽

Steady State Method ◽

State Method ◽

Kinetics Of

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Chlorine and Chlorinated Compounds Removal from Industrial Wastewater Discharges: A Review

Chiang Mai University Journal of Natural Sciences ◽

10.12982/cmujns.2021.047 ◽

2021 ◽

Vol 20 (3) ◽

Author(s):

Mohammad Al-Hwaiti ◽

Hamidi Abdul Aziz ◽

Mohd Azmier Ahmad ◽

Reyad Al-Shawabkeh

Keyword(s):

Industrial Wastewater ◽

Electrochemical Techniques ◽

Parent Compound ◽

Water Soluble ◽

Human Beings ◽

Catalytic Method ◽

Chlorinated Compounds ◽

Water Treatment Process ◽

Chlorine Removal ◽

Kinetics Of

Adsorption techniques for industrial wastewater treatment rich in heavy metals and aqueous solutions of water-soluble such as Cl−, F−, HCO3−, NO3−, SO2−4, and PO3−, often include technologies for toxicity removals. The recent advancement and technical applicability in the treatment of chlorine and chlorinated compounds from industrial wastewater are reviewed in this article. Chlorine and chlorinated compounds are among the common discharged constituents from numerous industries. They can be carcinogenic or naturally toxic and can pose issues to aquatic ecosystems and human beings. Thus, elimination of chlorides and chlorinated compounds from water or wastewater is inevitable to get rid of the problem. Several techniques are being applied for the reduction of chlorine and chlorinated compounds in water. These include biodegradation, photochemical, adsorption, chemical, electrochemical, photo-electrochemical, membrane, supercritical extraction and catalytic method. Chlorine can react with various organic and inorganic micro-pollutants. However, the potential reactivity of chlorine for specific compounds is small, and only minor variations in the structure of the parent compound are anticipated in the water treatment process under typical conditions. This paper reviews different techniques and aspects related to chlorine removal, the types of chlorine species in solution and their catalyst, chlorine fate and transport into the environment, electrochemical techniques for de-chlorination of water, kinetics, mechanisms of reduction of chlorinated compounds, and kinetics of the electrochemical reaction of chlorine compounds. Keywords: Industrial waste, Kinetics, Wastewater, Water purification

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Analysis of biochemical composition and antioxidant properties of nuts sold in the consumer marke

Proceedings of the Voronezh State University of Engineering Technologies ◽

10.20914/2310-1202-2020-2-124-130 ◽

2020 ◽

Vol 82 (2) ◽

pp. 124-130

Author(s):

L. P. Nilova ◽

S. M. Malyutenkova

Keyword(s):

Fatty Acids ◽

Vitamin E ◽

Phenolic Compounds ◽

Biochemical Composition ◽

Unsaturated Fatty Acids ◽

Antioxidant Properties ◽

Water Soluble ◽

Total Phenolic ◽

Consumer Market ◽

Triton X

The results of studies of the biochemical composition and antioxidant properties of nuts sold in the consumer market of St. Petersburg were presented in the work. The objects of research were kernels of nuts: sweet almonds, hazelnuts, cashews, walnuts. Total Soxhlet lipids, fatty acid composition, vitamin E, fractional composition of tocopherols and phytosterols, total phenolic compounds and flavonoids, antioxidant activity by FRAP with ferric chloride, o-phenanthroline and Triton X 100 were determined in nuts. Nuts varied in lipid content (42.6–65.4%) with a predominance of unsaturated fatty acids from 80.4 to 92.4 relative%. Oleic acid prevailed in the fatty acids of almonds, hazelnuts and cashews, while linoleic acid prevailed in walnuts. Walnuts contained the highest amount of polyunsaturated fatty acids. The antioxidant properties of nuts were formed by a complex of water and fat-soluble antioxidants. Fat-soluble antioxidants included vitamin E with a predominance of ?-tocopherol in the kernels of sweet almonds and hazelnuts, ?-tocopherol - in walnuts and cashews. Only sweet almond kernels contained all the tocopherol fractions. ?- and ?-tocopherols were absent in hazelnut lipids, while ?-tocopherols were absent in cashews and walnuts. ?-sitosterol, campesterol and stigmasterol with a predominance of ?-sitosterol were identified in the composition of phytosterols in all nut kernels. Water-soluble antioxidants are mainly represented by phenolic compounds, the amount of which varies widely depending on the type of nuts: cashews

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Water- and Fat-Soluble Antioxidants in Human Seminal Plasma and Serum of Fertile Males

Antioxidants ◽

10.3390/antiox8040096 ◽

2019 ◽

Vol 8 (4) ◽

pp. 96 ◽

Cited By ~ 7

Author(s):

Giacomo Lazzarino ◽

Ilaria Listorti ◽

Gabriele Bilotta ◽

Talia Capozzolo ◽

Angela Amorini ◽

...

Keyword(s):

Ascorbic Acid ◽

Uric Acid ◽

Vitamin E ◽

Vitamin C ◽

Seminal Plasma ◽

Sperm Count ◽

Venous Blood ◽

Water Soluble ◽

Human Seminal Plasma ◽

Serum Ratio

Reactive oxygen species (ROS) are physiologically involved in functions like sperm maturation, capacitation and acrosome reaction, but their excess is involved in male infertility. Antioxidants in seminal plasma (SP) are an important factor balancing physiologic and harmful ROS activities. In this study, we determined and compared the full profiles of the water- and fat-soluble antioxidants in SP and serum of 15 healthy fertile subjects (ranging between the ages of 35 and 42 years). Ejaculates were obtained after 2–5 days of sexual abstinence. After liquefaction and withdrawal of an aliquot for the sperm count, samples were centrifuged to obtain SP. Thirty min after semen donation, a venous blood sample was collected from each subject. Donors with lower SP concentrations of ascorbic acid (n = 5) or α-tocopherol (n = 5) received a 4 week oral administration of either vitamin C (100 mg/day) or vitamin E (30 mg/day). They were then re-assayed to determine the SP and serum levels of ascorbic acid and α-tocopherol. SP and serum samples were properly processed and analyzed by HPLC methods suitable to determine water (ascorbic acid, glutathione (GSH) and uric acid) and fat-soluble (all-trans-retinoic acid, all-trans-retinol, α-tocopherol, carotenoids and coenzyme Q10) antioxidants. Data demonstrate that only ascorbic acid is higher in SP than in serum (SP/serum ratio = 4.97 ± 0.88). The other water-soluble antioxidants are equally distributed in the two fluids (GSH SP/serum ratio = 1.14 ± 0.34; uric acid SP/serum ratio = 0.82 ± 0.12). All fat-soluble antioxidants are about 10 times less concentrated in SP than in serum. In donors treated with vitamin C or vitamin E, ascorbic acid and α-tocopherol significantly increased in both fluids. However, the SP/serum ratio of ascorbic acid was 4.15 ± 0.45 before and 3.27 ± 0.39 after treatment, whilst those of α-tocopherol were 0.11 ± 0.03 before and 0.10 ± 0.02 after treatment. The results of this study, by showing the peculiar composition in water- and fat-soluble antioxidants SP, indicate that it is likely that still-unknown mechanisms allow ascorbic acid accumulation in SP against a concentration gradient. SP mainly relies its defenses on water- rather than fat-soluble antioxidants and on the mechanisms ensuring their transfer from serum.

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