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Sample records for acid orange ii

  1. Ozonation of azo dyes (Orange II and Acid Red 27) in saline media

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    Silva, Alessandra C. [Chemical Engineering Program, COPPE, Federal University of Rio de Janeiro, Av. Horacio Macedo, 2030, P.O. Box, 68502, CEP 21941-972, Rio de Janeiro, RJ (Brazil); Pic, Jean Stephane [Institut National des Sciences Appliquees, INSA-GPE-LIPE, Toulouse (France); Sant' Anna, Geraldo L., E-mail: lippel@peq.coppe.ufrj.br [Chemical Engineering Program, COPPE, Federal University of Rio de Janeiro, Av. Horacio Macedo, 2030, P.O. Box, 68502, CEP 21941-972, Rio de Janeiro, RJ (Brazil); Dezotti, Marcia [Chemical Engineering Program, COPPE, Federal University of Rio de Janeiro, Av. Horacio Macedo, 2030, P.O. Box, 68502, CEP 21941-972, Rio de Janeiro, RJ (Brazil)

    2009-09-30

    Ozonation of two azo dyes was investigated in a monitored bench scale bubble column reactor (8.5-L), varying liquid media salt content (0, 1, 40 and 100 g L{sup -1}, NaCl). In experiments with Orange II pH was varied (5, 7.5 and 9) but ozonation of Acid Red 27 was performed at pH 7.5. Ozone self-decomposition rate-constant increased with salt concentration. Color removal was very effective and fast achieved under all experimental conditions. For the two azo dyes tested, more than 98% of color intensity was removed in 30-min ozonation assays. However, only partial mineralization of azo dyes (45%-Orange II; 20%-Acid Red 27) was attained in such experiments. The degree of mineralization (TOC removal) was negatively affected by salt concentration. Biodegradation assays conducted by respirometry revealed the inhibitory effect of dye degradation products formed during ozonation.

  2. Photoelectrochemical synergetic degradation of Acid Orange II with TiO2 modified β-PbO2 electrode

    Institute of Scientific and Technical Information of China (English)

    LI Guoting; QU Jiuhui; WU Rongcheng

    2005-01-01

    Electrochemically assisted photocatalysis is an effective approach to improve photocatalytic efficiency. In this paper, modified β-PbO2 electrode was prepared by TiO2 co-deposition and characterized by SEM and XRD. Then 2.0 g TiO2 modified β-PbO2 electrode (2.0 g TiO2 involved in the 200 mL co-deposition solution) was used in electrochemically assisted photocatalytic degradation of Acid Orange II and the influence of initial pH values was investigated when the potential applied across the electrodes was 1.5 V. When the potential applied was 2.5 V, the difference of the degradation process and the final products were studied. The results indicated that 2.0 g TiO2 modified β-PbO2 electrode was different from the unmodified one in that the β-PbO2 crystals became finer and the electrode became more compact and more uniform. The synergetic effect in electrochemically assisted photocatalytic degradation of Acid Orange II was observed and degradation efficiency and TOC removal were the highest at initial solution pH 2.0. By UV-visible spectral analysis, it was proved that photoelectrochemical synergetic degradation of Acid Orange II went through the step of producing main product maleic acid for the solution at the initial pH 2.0 within 2 h, but the degradation was slow for the solution at the initial pH 12.0.

  3. Process parameters for decolorization and biodegradation of orange II (Acid Orange 7) in dye-simulated minimal salt medium and subsequent textile effluent treatment by Bacillus cereus (MTCC 9777) RMLAU1.

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    Garg, Satyendra Kumar; Tripathi, Manikant

    2013-11-01

    In this study, Bacillus cereus isolate from tannery effluent was employed for orange II dye decolorization in simulated minimal salt broth and textile effluent. Most of the physicochemical parameters of textile effluent were above the permissible limits. The strain was highly tolerant to dye up to 500 mg l(-1). Increasing dye concentration exerted inhibitory effect on the bacterial growth and decolorization. The maximum decolorization of initial 100 mg dye l(-1) was achieved at optimum pH 8.0 and 33 °C under static culture conditions during 96-h incubation. Supplementation with optimized glucose (0.4%, w/v) and ammonium sulfate (0.1%, w/v) with 3.0% B. cereus inoculum further enhanced dye decolorization to highest 68.5% within 96-h incubation. A direct correlation was evident between bacterial growth and dye decolorization. Under above optimized conditions, 24.3% decolorization of unsterilized real textile effluent by native microflora was achieved. The effluent decolorization enhanced substantially to 37.1% with B. cereus augmentation and to 40.5% when supplemented with glucose and ammonium sulfate without augmentation. The maximum decolorization of 52.5% occurred when textile effluent was supplemented with optimized exogenous carbon and nitrogen sources along with B. cereus augmentation. Gas chromatography-mass spectrometry identified sulfanilic acid as orange II degradation product. Fourier transform infra red spectroscopy of metabolic products indicated the presence of amino and hydroxyl functional groups. This strain may be suitably employed for in situ decolorization of textile industrial effluent under broad environmental conditions.

  4. Determination of Orange II in food samples after cloud point extraction using mixed micelles.

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    Pourreza, N; Zareian, M

    2009-06-15

    In this paper, a cloud point extraction method for the determination of trace amounts of Orange II by spectrophotometry is described. The method is based on the extraction of Orange II from aqueous solution using mixed micelles of non-ionic surfactant, Triton X-100 and cationic surfactant cetyltrimethyl ammonium bromide (CTAB) in acidic media. The extracted surfactant rich phase is diluted with water and its absorbance is measured at 484 nm by a spectrophotometer. The effects of surfactant, acid and salt concentration, incubation time and temperature were investigated. The calibration graph was linear in the range of 2.1-420 ng mL(-1) of Orange II in the initial solution with r=0.9991 (n=12). Detection limit based on three times the standard deviation of the blank (3S(b)) was 0.67 ng mL(-1) and the relative standard deviation (RSD) for 35 and 105 ng mL(-1) of Orange II was 1.20% and 1.49% (n=10), respectively. The method was applied to the determination of Orange II in different food samples.

  5. Application of Acid Whey in Orange Drink Production

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    Grażyna Jaworska

    2013-01-01

    Full Text Available The aim of this study is to compare qualitative changes in orange and orange beverages containing whey during 12 months of storage. The beverages contained 12 % extract, half of which was orange concentrate, the rest was sugar or sugar and whey extract. Acid whey was used in the production of beverages, added at a rate of 50 % of the used water. Orange beverages with whey contained more protein, ash, glucose, lactose and vitamin B2 than the orange beverages, but less sucrose, fructose and vitamin C, and also showed lower antioxidant activity against the DPPH radical. No significant differences between the two types of beverages were found in the polyphenolic content or activity against the ABTS cation radical. The type of beverage had a significant effect on the colour parameter values under the CIELAB system, although no significant differences were found between the beverages in the sensory evaluation of colour desirability. The overall sensory evaluation of orange beverages with whey was 2–10 % lower than of other orange beverages. The intensity of orange, sweet and refreshing taste was greater in orange beverages, while that of sour and whey taste was greater in orange beverages containing whey. There were significant decreases in sucrose, lactose, all indicators of antioxidant activity and sensory quality during storage. Levels of glucose and fructose rose with the storage period, while the intensity of sour, orange and refreshing taste decreased.

  6. An Improved Method for Removal of Azo Dye Orange II from Textile Effluent Using Albumin as Sorbent

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    Tadashi Ohashi

    2012-11-01

    Full Text Available Azo dyes are generally resistant to biodegradation due to their complex structures. Acid orange II is one of the most widely used dyes in the textile industry. The influence of bovine serum albumin (BSA in different concentrations, pH, and time of contact on Orange II was investigated using kinetics and adsorption-isotherm experiments. The results showed that the maximum colour removed from dye/albumin was 99.50% and that a stable dye-protein complex had been formed at pH 3.5 and in a proportion of 1:3 (v/v, respectively. The synthetic effluent did not show toxicity to the microcrustacean Artemia salina, and showed a CL50 equal to 97 µg/mL to azo dye orange II. Additionally, the methodology was effective in removing the maximum of orange II using BSA by adsorption at pH 3.5 which mainly attracted ions to the azo dye during the adsorption process. This suggests that this form of treatment is economical and easy to use which potentially could lead to bovine serum albumin being used as a sorbent for azo dyes.

  7. An improved method for removal of azo dye orange II from textile effluent using albumin as sorbent.

    Science.gov (United States)

    Ohashi, Tadashi; Jara, Alícia M T; Batista, Anabelle C L; Franco, Luciana O; Barbosa Lima, Marcos A; Benachour, Mohand; Alves da Silva, Carlos A; Campos-Takaki, Galba M

    2012-11-30

    Azo dyes are generally resistant to biodegradation due to their complex structures. Acid orange II is one of the most widely used dyes in the textile industry. The influence of bovine serum albumin (BSA) in different concentrations, pH, and time of contact on Orange II was investigated using kinetics and adsorption-isotherm experiments. The results showed that the maximum colour removed from dye/albumin was 99.50% and that a stable dye-protein complex had been formed at pH 3.5 and in a proportion of 1:3 (v/v), respectively. The synthetic effluent did not show toxicity to the microcrustacean Artemia salina, and showed a CL₅₀ equal to 97 µg/mL to azo dye orange II. Additionally, the methodology was effective in removing the maximum of orange II using BSA by adsorption at pH 3.5 which mainly attracted ions to the azo dye during the adsorption process. This suggests that this form of treatment is economical and easy to use which potentially could lead to bovine serum albumin being used as a sorbent for azo dyes.

  8. One-step green synthesis of bimetallic Fe/Pd nanoparticles used to degrade Orange II

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    Luo, Fang; Yang, Die; Chen, Zuliang, E-mail: zuliang.chen@newcastle.edu.au; Megharaj, Mallavarapu; Naidu, Ravendra

    2016-02-13

    Highlights: • Green synthesis of bimetallic Fe/Pd NPs was firstly reported using the one-step method. • 98.0% of Orange II was removed by Fe/Pd NPs, but only 16.0% by Fe NPs. • Fe/Pd NPs with a diameter ranging from 10 to 100 nm were observed. • Removing Orange II using Fe/Pd NPs involved both adsorption and catalytic degradation. - Abstract: To reduce cost and enhance reactivity, bimetallic Fe/Pd nanoparticles (NPs) were firstly synthesized using grape leaf aqueous extract to remove Orange II. Green synthesized bimetallic Fe/Pd NPs (98.0%) demonstrated a far higher ability to remove Orange II in 12 h compared to Fe NPs (16.0%). Meanwhile, all precursors, e.g., grape leaf extract, Fe{sup 2+} and Pd{sup 2+}, had no obvious effect on removing Orange II since less than 2.0% was removed. Kinetics study revealed that the removal rate fitted well to the pseudo-first-order reduction and pseudo-second-order adsorption model, meaning that removing Orange II via Fe/Pd NPs involved both adsorption and catalytic reduction. The remarkable stability of Fe/Pd NPs showed the potential application for removing azo dyes. Furthermore, Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the changes in Fe/Pd NPs before and after reaction with Orange II. High Performance Liquid Chromatography–Mass Spectrum (HPLC–MS) identified the degraded products in the removal of Orange II, and finally a removal mechanism was proposed. This one-step strategy using grape leaf aqueous extract to synthesize Fe/Pd NPs is simple, cost-effective and environmentally benign, making possible the large-scale production of Fe/Pd NPs for field remediation.

  9. One-step green synthesis of bimetallic Fe/Pd nanoparticles used to degrade Orange II.

    Science.gov (United States)

    Luo, Fang; Yang, Die; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2016-02-13

    To reduce cost and enhance reactivity, bimetallic Fe/Pd nanoparticles (NPs) were firstly synthesized using grape leaf aqueous extract to remove Orange II. Green synthesized bimetallic Fe/Pd NPs (98.0%) demonstrated a far higher ability to remove Orange II in 12h compared to Fe NPs (16.0%). Meanwhile, all precursors, e.g., grape leaf extract, Fe(2+) and Pd(2+), had no obvious effect on removing Orange II since less than 2.0% was removed. Kinetics study revealed that the removal rate fitted well to the pseudo-first-order reduction and pseudo-second-order adsorption model, meaning that removing Orange II via Fe/Pd NPs involved both adsorption and catalytic reduction. The remarkable stability of Fe/Pd NPs showed the potential application for removing azo dyes. Furthermore, Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the changes in Fe/Pd NPs before and after reaction with Orange II. High Performance Liquid Chromatography-Mass Spectrum (HPLC-MS) identified the degraded products in the removal of Orange II, and finally a removal mechanism was proposed. This one-step strategy using grape leaf aqueous extract to synthesize Fe/Pd NPs is simple, cost-effective and environmentally benign, making possible the large-scale production of Fe/Pd NPs for field remediation. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Reduced acid frozen concentrated orange juice. 146... SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced...

  11. Strategies comparison of eliminating the passivation of non-aromatic intermediates in degradation of Orange II by Fe{sup 3+}/H{sub 2}O{sub 2}

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    Chen Feng, E-mail: fengchen@ecust.edu.cn [Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Li Yan, E-mail: liyan235235@sohu.com [Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Guo Liqin, E-mail: cloud1133@163.com [Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Zhang Jinlong, E-mail: jlzhang@ecust.edu.cn [Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China)

    2009-09-30

    The degradation kinetics of Orange II by Fe{sup 3+}/H{sub 2}O{sub 2} was examined under various conditions in the presence of the non-aromatic organic intermediates such as malonic acid (MA), oxalic acid (OX) and EDTA. Various strategies were adopted to eliminate the passivation of the non-aromatic organic intermediates in the Fenton-like degradation of Orange II. UV irradiation, visible irradiation, hydroquinone (HQ) additive and their hybrid were used to accelerate the decoloration of Orange II; however, some of them were failed to show a good performance in the presence of non-aromatic organics, especially for the mineralization of Orange II. Aluminum ions additive released the ferric ions via a competitive chelation process, and accelerated the reaction obviously. From the decoloration and the mineralization data of Orange II, UV irradiation combined with Al{sup 3+} ion additive was regarded as the most favorable strategy for deep mineralization of Orange II by Fe{sup 3+}/H{sub 2}O{sub 2} in the presence of non-aromatic intermediates. However, by considering the decoloration of Orange II with moderate mineralization, the combination of visible irradiation and Al{sup 3+} ion additive might present the best performance.

  12. Degradation of acid orange 7 in an aerobic biofilm.

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    Coughlin, Michael F; Kinkle, Brian K; Bishop, Paul L

    2002-01-01

    A stable microbial biofilm community capable of completely mineralizing the azo dye acid orange 7 (AO7) was established in a laboratory scale rotating drum bioreactor (RDBR) using waste liquor from a sewage treatment plant. A broad range of environmental conditions including pH (5.8-8.2), nitrification (0.0-4.0 mM nitrite), and aeration (0.2-6.2 mg O2 l(-1)) were evaluated for their effects on the biodegradation of AO7. Furthermore the biofilm maintained its biodegradative ability for over a year while the effects of these environmental conditions were evaluated. Reduction of the azo bond followed by degradation of the resulting aromatic amine appears to be the mechanism by which this dye is biodegraded. Complete loss of color, sulfanilic acid, and chemical oxygen demand (COD) indicate that AO7 is mineralized. To our knowledge this is the first reported occurrence of a sulfonated phenylazonaphthol dye being completely mineralized under aerobic conditions. Two bacterial strains (ICX and SAD4i) originally isolated from the RDBR were able to mineralize, in co-culture, up to 90% of added AO7. During mineralization of AO7, strain ICX reduces the azo bond under aerobic conditions and consumes the resulting cleavage product 1-amino-2-naphthol. Strain SAD4i consumes the other cleavage product, sulfanilic acid. The ability of the RDBR biofilm to aerobically mineralize an azo dye without exogenous carbon and nitrogen sources suggests that this approach could be used to remediate industrial wastewater contaminated with spent dye.

  13. Effect of acid orange 7 on nitrification process

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    He, Yongjie (ManTech Environmental Tech., Inc., Dayton, OH (United States)); Bishop, P.L. (Univ. of Cincinnati, OH (United States). Dept. of Civil and Environmental Engineering)

    The effect of Acid Orange 7 (AO7), an azo dye commonly used in textile, pharmaceutical, food, and cosmetic industries, on the nitrification process is studied using completely stirred tank reactors (CSTR) and batch treatment systems. Azo dyes are of concern because many of the dyes or their metabolic intermediates are carcinogenic. AO7 biodegradation is found to be essentially complete when solids retention times (SRT) are maintained above 7.5 days, but systems with lower SRTs are unstable. It is shown that AO7 inhibits all stages of the nitrification process. Nitrite oxidizers are found to be more sensitive to AO7 than ammonium oxidizers. The results of kinetic studies indicate that the inhibition of ammonium oxidation is typified by noncompetitive inhibition; the presence of AO7 decreases the maximum substrate utilization rate and very slightly increases K[sub s], the half-saturation constant. AO7 is found to be less toxic to nitrification than some metal and phenolic compounds, but more toxic than some common organic compounds such as formalin, methanol, or acetone.

  14. Ascorbic Acid Determination in Natural Orange Juice: As a Teaching Tool of Coulometry and Polarography.

    Science.gov (United States)

    Bertotti, Mauro; And Others

    1995-01-01

    Describes an experiment designed to determine ascorbic acid concentrations in natural orange juice. The experiment is used with undergraduate pharmacy students to allow understanding of the principles of operation of the coulometer and polarograph. (DDR)

  15. Adsorption characteristics of Orange II and Chrysophenine on sludge adsorbent and activated carbon fibers.

    Science.gov (United States)

    Hsiu-Mei, Chiang; Ting-Chien, Chen; San-De, Pan; Chiang, Hung-Lung

    2009-01-30

    Sludge adsorbent (SA) and commercial activated carbon fibers (ACFC and ACFT) were applied to Orange II and Chrysophenine (CH) adsorption (BET surface area: ACFC>ACFT>SA). ACFT was primarily in the micropore range, while SA was approximately 500 A (macropore) and 80 A (mesopore). The ACFC pore volume was high in both the mesopore and micropore regions. Measurement of the oxygen surface functional groups of the adsorbents using Boehm's titration method showed a similar distribution on the carbon fibers (mainly in the carbonyl group), while SA was mainly in the carboxyl, lactone and phenolic groups. The SA, ACFC and ACFT adsorption capacities of Orange II (30-80 mg/l) ranged from 83 to 270, 209-438, and 25-185 mg/g at temperatures ranging from 10 to 60 degrees C, respectively. CH concentration ranged from 30 to 80 mg/l, corresponding to SA and ACFC adsorption capacities of 39-191 and 48-374 mg/g over the defined temperature range, from 10 to 60 degrees C. CH adsorption on ACFT was low. The adsorption capacity of Orange II on ACFT was lower than on SA at 10 degrees C, but at higher temperatures the Orange II molecules were transported into the ACFT, producing an adsorption capacity similar to that of SA. Mass transfer increased with temperature, overcoming the adsorption energy barrier. Overall, SA and ACFC were more effective than ACFT.

  16. Discoloration and mineralization of Orange II using different heterogeneous catalysts containing Fe: a comparative study.

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    Feng, Jiyun; Hu, Xijun; Yue, Po Lock

    2004-11-01

    Four heterogeneous catalysts containing Fe including a bentonite-clay-based Fe nanocomposite (Fe-B), hematite (alpha-Fe2O3), amorphous FeOOH, and calcined FeOOH (denoted as FeOOH-M) were employed for the photo-Fenton discoloration and mineralization of 0.2 mM Orange II in the presence of 10 mM H2O2 and 8 W UVC at two different initial solution pH values (3.0 and 6.6). It was found that, at an initial solution pH of 3.0, their photocatalytic activities follow the order Fe-B > FeOOH, FeOOH-M > alpha-Fe2O3. When the Fe-B nanocomposite, FeOOH, and FeOOH-M were used as heterogeneous catalysts, both heterogeneous and homogeneous photo-Fenton reactions were responsible for the discoloration and mineralization of 0.2 mM Orange II because homogeneous photo-Fenton reaction occurred due to the presence of Fe ions leached from the catalysts. At an initial solution pH of 6.6, their photocatalytic activities still follow the order Fe-B > FeOOH, FeOOH-M > alpha-Fe2O3. However, only heterogeneous photo-Fenton reaction accounted for the discoloration and mineralization of 0.2 mM Orange II because Fe leaching from the catalysts was significantly depressed. In the case of alpha-Fe2O3 as a catalyst, whether at an initial solution pH of 3.0 or 6.6, only heterogeneous photo-Fenton reaction happened for the discoloration and mineralization of 0.2 mM Orange II because Fe leaching from the catalyst is negligible. The apparent discoloration kinetics of Orange II with the four catalysts at two different initial solution pH values was also investigated.

  17. Effect of fermentation and subsequent pasteurization processes on amino acids composition of orange juice.

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    Cerrillo, I; Fernández-Pachón, M S; Collado-González, J; Escudero-López, B; Berná, G; Herrero-Martín, G; Martín, F; Ferreres, F; Gil-Izquierdo, A

    2015-06-01

    The fermentation of fruit produces significant changes in their nutritional composition. An orange beverage has been obtained from the controlled alcoholic fermentation and thermal pasteurization of orange juice. A study was performed to determine the influence of both processes on its amino acid profile. UHPLC-QqQ-MS/MS was used for the first time for analysis of orange juice samples. Out of 29 amino acids and derivatives identified, eight (ethanolamine, ornithine, phosphoethanolamine, α-amino-n-butyric acid, hydroxyproline, methylhistidine, citrulline, and cystathionine) have not previously been detected in orange juice. The amino acid profile of the orange juice was not modified by its processing, but total amino acid content of the juice (8194 mg/L) was significantly increased at 9 days of fermentation (13,324 mg/L). Although the pasteurization process produced partial amino acid degradation, the total amino acid content was higher in the final product (9265 mg/L) than in the original juice, enhancing its nutritional value.

  18. Retention of ascorbic acid in fortified orange juice powers during storage

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    G. S. Siddappa

    1960-10-01

    Full Text Available Both Coorg and Sathgudi orange juice powders are good carriers for added ascorbic acid during prolonged storage at ordinary temperatures. There is not much difference between nitrogen and air packs as regards retention of ascorbic acid during storage. Nitrogen pack, however, helps to keep the power in a better free-flowing condition.

  19. Citric acid production from orange peel wastes by solid-state fermentation

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    Ana María Torrado

    2011-03-01

    Full Text Available Valencia orange (Citrus sinensis peel was employed in this work as raw material for the production of citric acid (CA by solid-state fermentation (SSF of Aspergillus niger CECT-2090 (ATCC 9142, NRRL 599 in Erlenmeyer flasks. To investigate the effects of the main operating variables, the inoculum concentration was varied in the range 0.5·10³ to 0.7·10(8 spores/g dry orange peel, the bed loading from 1.0 to 4.8 g of dry orange peel (corresponding to 35-80 % of the total volume, and the moisture content between 50 and 100 % of the maximum water retention capacity (MWRC of the material. Moreover, additional experiments were done adding methanol or water in different proportions and ways. The optimal conditions for CA production revealed to be an inoculum of 0.5·10(6 spores/g dry orange peel, a bed loading of 1.0 g of dry orange peel, and a humidification pattern of 70 % MWRC at the beginning of the incubation with posterior addition of 0.12 mL H2O/g dry orange peel (corresponding to 3.3 % of the MWRC every 12 h starting from 62 h. The addition of methanol was detrimental for the CA production. Under these conditions, the SSF ensured an effective specific production of CA (193 mg CA/g dry orange peel, corresponding to yields of product on total initial and consumed sugars (glucose, fructose and sucrose of 376 and 383 mg CA/g, respectively. These results, which demonstrate the viability of the CA production by SSF from orange peel without addition of other nutrients, could be of interest to possible, future industrial applications.

  20. Enhanced Adsorption of Orange II Using Cationic Surfactant Modified Biochar Pyrolyzed from Cornstalk

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    Xiao Mi

    2016-01-01

    Full Text Available As dissolution of raw biomass is serious when used as an adsorbent, the cheap biochar pyrolyzed from biomass might be a good matrix. Raw cornstalk biochar was intentionally modified by cetyltrimethylammonium bromide (CTAB to prepare the composite adsorbent designed for the removal of negatively charged pollutants. After modification, the removal efficiency for anionic dye Orange II (ORII increased from 46.9% of the virgin cornstalk biochar to 99.7% of the CTAB-modified cornstalk biochar. The uptake of ORII proved to be favorable under acidic conditions but unfavorable under alkaline conditions. By nonlinear simulation, the Elovich model was the best to describe the adsorption kinetics. For linear simulation of the kinetic data, the pseudo-second-order kinetic model fitted the experimental points better than the pseudo-first-order model. Kinetic analysis indicated that the ORII adsorption process on the CTAB-modified cornstalk biochar might be chemical adsorption accompanied by ion exchange. At 298 K, the maximal adsorption capacity of the modified biochar is 26.9 mg/g by the Langmuir model. The adsorption of ORII increased with a rise in the reaction temperature. The enthalpy and entropy of the adsorption process are calculated to be 38.45 KJ mol−1 and 185.0 J mol−1 K−1, respectively. The negative values of ΔG0 at 288, 298, and 308 K were −14.92, −16.50, and −18.62 KJ mol−1, respectively. The above thermodynamic analysis demonstrates that the adsorption process was endothermic and spontaneous.

  1. Texture effect of layered double hydroxides on chemisorption of Orange II

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    Géraud, Erwan; Bouhent, Mustapha; Derriche, Zoubir; Leroux, Fabrice; Prévot, Vanessa; Forano, Claude

    2007-05-01

    The chemisorption properties of hydrotalcite (HT) with novel macroporous properties have been investigated for azo dye, Orange II (O-II), and compared to coprecipitated HT and their calcined derivatives. Adsorption isotherms satisfactorily fit the Langmuir model. Adsorption capacities of the layered double hydroxides (LDH) macroporous structures are very high, particularly for the calcined materials (4.34 mmol/g) compared to standard HT (0.504 mmol/g), showing that accessibility to the LDH layer surface insures better sorptive properties. For both synthetic materials, the calcination/reconstruction process gives rise to highest concentrations of adsorbed O-II and a partial intercalation of O-II molecules in the structure as shown by the expansion of the basal spacing (d=2.4nm). Conversely, the uncalcined HT phases mainly display a surface exchange chemisorption process.

  2. Poly(lactic acid) and Osage Orange Wood Fiber Composites for Agricultural Mulch Films

    Science.gov (United States)

    Osage orange wood(OO)was combined with poly(lactic acid)(PLA)to form a polymer composite intended for use as an agricultural mulch film. The PLA-OO mechanical properties were comparable to existing mulch film products and had the advantage of being completely biodegradable through a single growing ...

  3. STUDI PENURUNAN ZAT WARNA ACID ORANGE 7 DENGAN PROSES OKSIDASI MENGGUNAKAN FERRAT (FeO42-

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    Dian Windy Dwiasi

    2011-05-01

    Full Text Available Colour removal from textile wastewater has been a matter of considerable interest during the last two decades, not only because of the potential toxicity of certain dyes but often due to their visibility in receiving waters and to their low biodegradability. Due to the limited success of some physical and chemical techniques for the treatment of dye effluents it is necessary to develop destructive systems leading to complete mineralization or, at least, to less harmful or easy-to-treat compounds. Oxidation processes using ferrate (FeO42- have been found to be very effective in the degradation of dye pollutants and for the treatment of waste waters from the textile industry. Acid Orange 7 (AO7 commonly used as a textile dye and could be degraded by ferrate oxidation processes. In the oxidation degradation of dye by ferrate process, effect of some parameters such as time, pH, and molar ratio of dye was examined at experimental condition. AO7 removal by this process was calculated to be equal to 12 minute at experimental condition. Ferrate can oxidize acid orange 7 effectively at optimum pH of 9.8, with the molar ratio of ferrate : acid orange 7 at 4:1. The percentages of acid orange 7 degradation reached to 98.9%.

  4. Adsorption of Azo-Dye Orange II from Aqueous Solutions Using a Metal-Organic Framework Material: Iron- Benzenetricarboxylate

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    Elizabeth Rojas García

    2014-12-01

    Full Text Available A Metal-Organic Framework (MOF, iron-benzenetricarboxylate (Fe(BTC, has been studied for the adsorptive removal of azo-dye Orange II from aqueous solutions, where the effect of various parameters was tested and isotherm and kinetic models were suggested. The adsorption capacities of Fe(BTC were much higher than those of an activated carbon. The experimental data can be best described by the Langmuir isotherm model (R2 > 0.997 and revealed the ability of Fe(BTC to adsorb 435 mg of Orange II per gram of adsorbent at the optimal conditions. The kinetics of Orange II adsorption followed a pseudo-second-order kinetic model, indicating the coexistence of physisorption and chemisorption, with intra-particle diffusion being the rate controlling step. The thermodynamic study revealed that the adsorption of Orange II was feasible, spontaneous and exothermic process (−25.53 kJ·mol−1. The high recovery of the dye showed that Fe(BTC can be employed as an effective and reusable adsorbent for the removal of Orange II from aqueous solutions and showed the economic interest of this adsorbent material for environmental purposes.

  5. Adsorption of Azo-Dye Orange II from Aqueous Solutions Using a Metal-Organic Framework Material: Iron- Benzenetricarboxylate

    Science.gov (United States)

    Rojas García, Elizabeth; López Medina, Ricardo; May Lozano, Marcos; Hernández Pérez, Isaías; Valero, Maria J.; Maubert Franco, Ana M.

    2014-01-01

    A Metal-Organic Framework (MOF), iron-benzenetricarboxylate (Fe(BTC)), has been studied for the adsorptive removal of azo-dye Orange II from aqueous solutions, where the effect of various parameters was tested and isotherm and kinetic models were suggested. The adsorption capacities of Fe(BTC) were much higher than those of an activated carbon. The experimental data can be best described by the Langmuir isotherm model (R2 > 0.997) and revealed the ability of Fe(BTC) to adsorb 435 mg of Orange II per gram of adsorbent at the optimal conditions. The kinetics of Orange II adsorption followed a pseudo-second-order kinetic model, indicating the coexistence of physisorption and chemisorption, with intra-particle diffusion being the rate controlling step. The thermodynamic study revealed that the adsorption of Orange II was feasible, spontaneous and exothermic process (−25.53 kJ·mol−1). The high recovery of the dye showed that Fe(BTC) can be employed as an effective and reusable adsorbent for the removal of Orange II from aqueous solutions and showed the economic interest of this adsorbent material for environmental purposes. PMID:28788289

  6. Retention of Ascorbic Acid and Solid Concentration via Centrifugal Freeze Concentration of Orange Juice

    Directory of Open Access Journals (Sweden)

    P. Orellana-Palma

    2017-01-01

    Full Text Available Freeze concentration of liquid foods produces high-quality concentrates while retaining the heat-labile compounds found in fresh samples. Centrifugal freeze concentration is a cryoconcentration method assisted by an external force, centrifugation, to enhance the separation of concentrate from the ice. When applying centrifugal freeze concentration to orange juice, after the third cryoconcentration cycle, the ascorbic acid content in the concentrate showed retention close to 70% of the initial value. After the third cycle, the solutes in the concentrate increased 4 times the initial value of the fresh sample with 70% efficiency. The color evaluation showed that the final concentrated fraction was darker than the fresh juice. The centrifugal freeze concentration in orange juice was effective for obtaining a high-quality concentrate with a higher concentration of solids and ascorbic acid retention.

  7. Photodegradation of Orange II using waste paper sludge-derived heterogeneous catalyst in the presence of oxalate under ultraviolet light emitting diode irradiation.

    Science.gov (United States)

    Zhou, Guoqiang; Guo, Jinyi; Zhou, Guowang; Wan, Xiankai; Shi, Huixiang

    2016-09-01

    A waste paper sludge-derived heterogeneous catalyst (WPS-Fe-350) was synthesized via a facile method and successfully applied for the degradation of Orange II in the presence of oxalic acid under the illumination of ultraviolet light emitting diode (UV-LED) Powder X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electronic microscopy and N2 sorption isotherm analysis indicated the formation of α-Fe2O3 in the mesoporous nanocomposite. The degradation test showed that WPS-Fe-350 exhibited rapid Orange II (OII) degradation and mineralization in the presence of oxalic acid under the illumination of UV-LED. The effects of pH, oxalic acid concentration and dosage of the catalyst on the degradation of OII were evaluated, respectively. Under the optimal conditions (1g/L catalyst dosage, 2mmol/L oxalic acid and pH3.0), the degradation percentage for a solution containing 30mg/L OII reached 83.4% under illumination by UV-LED for 80min. Moreover, five cyclic tests for OII degradation suggested that WPS-Fe-350 exhibited excellent stability of catalytic activity. Hence, this study provides an alternative environmentally friendly way to reuse waste paper sludge and an effective and economically viable method for degradation of azo dyes and other refractory organic pollutants in water. Copyright © 2016. Published by Elsevier B.V.

  8. Evaluation of heterogeneous photo-Fenton oxidation of Orange II using response surface methodology.

    Science.gov (United States)

    Gong, Y H; Zhang, H; Li, Y L; Xiang, L J; Royer, S; Valange, S; Barrault, J

    2010-01-01

    A mesoporous SBA-15 doped iron oxide (Fe2O3/SBA-15) was synthesized by co-condensation, characterized and used as heterogeneous catalysts for the photo-Fenton decolorization of azo dye Orange II under UV irradiation. Response surface methodology (RSM) was used to investigate operating condition effects, such as hydrogen peroxide concentration, initial pH and catalyst loadings, on the decolorization rate. UV irradiation is found to enhance the activity of the catalyst in the process. RSM analysis evidenced the influence of the initial pH value and H2O2 concentration on the dye degradation rate. The coupled UV/Fe2O3/SBA-15/H2O2 process at room temperature is revealed as a promising friendly process for wastewater treatment. Indeed, the use of a heterogeneous catalyst allows an easy active phase recycling without multi-step recovering while the heterogeneous catalyst used here exhibits high catalytic activity for the reaction considered.

  9. Visible light degradation of Orange II using xCuyOz/TiO2 heterojunctions.

    Science.gov (United States)

    Helaïli, N; Bessekhouad, Y; Bouguelia, A; Trari, M

    2009-08-30

    Cu(2)O/TiO(2), Cu/Cu(2)O/TiO(2) and Cu/Cu(2)O/CuO/TiO(2) heterojunctions were prepared and studied for their potential application as photocatalysts able to induce high performance under visible light. Orange II was used as a representative dye molecule. The effect of the amount and composition of the photosensitizers toward the activation of TiO(2) was studied. In each case, the global mechanism of Inter Particle Electrons Injection (IPEI) was discussed. The highest photocatalytic activity was observed for the system Cu/Cu(2)O/CuO (MB2 catalyst) under visible light (t(1/2)=24 min, k=159.7 x 10(-3)min(-1)) and for the heterojunction cascade Cu/Cu(2)O/CuO/TiO(2) (MB2 (50%)/TiO(2)) under UV-vis light (t(1/2)=4 min, k=1342 x 10(-3)min(-1)). In the last case, the high performance was attributed firstly to the electromotive forces developed under this configuration in which CuO energy bands mediate the electrons transfer from Cu(2)O to TiO(2). The formation of monobloc sensitizers also accounts for the decrease of the probability of the charges lost. It was demonstrated that "Cu(2)O/CuO" governs the capability of the heterojunction cascade and Cu does not play a significant role regardless of the heterojunction cascade efficiency. The electrical energy consumption per order of magnitude for photocatalytic degradation of Orange II was investigated for some representative catalytic systems. Visible/MB2 and UV/vis MB2 (50%)/TiO(2) exhibited respectively 0.340 and 0.05 kW hm(-3) demonstrating the high efficiency of the systems.

  10. BIOSORPTION STUDIES OF CADMIUM (II IONS FROM AQUEOUS SOLUTIONS ONTO ORANGE RIND (CITRUS SINENSIS L. OSBECK

    Directory of Open Access Journals (Sweden)

    Satish A. Bhalerao

    2015-03-01

    Full Text Available The biosorption studies for effective removal of cadmium (II ions from aqueous solutions using orange rind (Citrus sinensis L. Osbeck, cost effective biosorbent, was carried out in batch system. FTIR analysis of biosorbent confirmed that carboxyl, hydroxyl, carbonyl group which was responsible for biosorption of cadmium (II ions. The SEM represents porous structure with surface area. The effects of operational factors including solution pH, biosorbent dose, initial cadmium (II ions concentration, contact time and temperature were studied. The optimum solution pH for cadmium (II ions biosorption by biosorbent was 7.0 with the optimal removal 80.30 %. The biosorbent dose 5 mg/ml was enough for optimal removal of 65.15 %. The biosorption process was relatively fast and equilibrium was achieved after 90 minutes of contact. The experimental equilibrium biosorption data were analysed by four widely used two-parameters Langmuir, Freundlich, Dubinin-Kaganer-Redushkevich (DKR and Temkin isotherm models. Langmuir isotherm model provided a better fit with the experimental data than Freundlich, Temkin and Dubinin-Kaganer-Redushkevich (DKR isotherm models by high correlation coefficient value (R2 = 0.911. The maximum adsorption capacity determined from Langmuir isotherm was found to be 83.33 mg/g of biosorbent. Simple kinetic models such as pseudo-first-order, pseudo-second-order, Elovich equation and Weber and Morris intra-particle diffusion rate equation were employed to determine the adsorption mechanism. Results clearly indicates that the pseudo-second-order kinetic model (R2 = 0.998 was found to be correlate the experimental data strongest than other three kinetic models and this suggests that chemical adsorption process was more dominant. Thermodynamic study revealed that the biosorption process was spontaneous, endothermic and increasing randomness of the solid solution interfaces. Orange rind (Citrus sinensis L. Osbeck was successfully used for the

  11. Oxalate enhanced mechanism of hydroxyl-Fe-pillared bentonite during the degradation of Orange II by UV-Fenton process.

    Science.gov (United States)

    Chen, Jianxin; Zhu, Lizhong

    2011-01-30

    An enhanced method of hydroxyl-Fe-pillared bentonite (H-Fe-P-B) during the degradation of Orange II was studied to provide novel insight to interactions of degradation intermediates with heterogeneous catalyst in UV-Fenton system. Based on the degradation mechanism of Orange II, oxalate enhanced mechanism of H-Fe-P-B in heterogeneous UV-Fenton system was developed. The results showed that additional oxalate could increase the Fe leaching of H-Fe-P-B during heterogeneous UV-Fenton process, which led to higher mineralization efficiency of Orange II and lower energy consumption of treatment. When the concentrations of additional sodium oxalate increased up to 0.1 mmol L(-1), 0.2 mmol L(-1) and 0.4 mmol L(-1), the rate of Orange II degradation could increase 30%, 46% and 63%, respectively. The iron ions leached from catalyst could be adsorbed back to the catalyst again after the organic intermediates were mineralized completely. Then the catalyst of H-Fe-P-B could be reused and additional pollution caused by iron ions could be avoided.

  12. Response of `Nagpur' mandarin, `Mosambi' sweet orange and `Kagzi' acid lime to gamma radiation

    Science.gov (United States)

    Ladaniya, M. S.; Singh, Shyam; Wadhawan, A. K.

    2003-07-01

    The effects of irradiation dose and refrigerated storage conditions on 'Nagpur' mandarin ( Citrus reticulata Blanco), 'Mosambi' sweet orange ( Citrus sinensis Osbeck) and 'Kagzi' acid lime ( Citrus aurantifolia Swingle) were investigated. Mature fruits of these three species were treated with 0, 0.25, 0.5, 1 and 1.5 kGy radiation. 'Nagpur' mandarin and 'Mosambi' sweet oranges were stored at 6-7°C and 90-95% r.h. for 75 and 90 days, respectively, while 'Kagzi' acid limes were stored at 8±1°C and 90-95% r.h. for 90 days. Physico-chemical parameters, sensory attributes and respiration rate were measured besides losses and disorders. In 'Nagpur' mandarin, radiation dose upto 1.5 kGy did not cause any rind disorder. Radiation treatments did not reduce the extent of decay. Penicillium rot was delayed in fruit treated with 1.5 kGy, while it appeared early in 0 kGy. Irradiation doses were ineffective to control rots due to Botryodiplodia theobromae and Alternaria citri. Doses upto 1.5 kGy did not cause any significant effect on fruit firmness and juice content; however, total soluble solids increased, while titratable acidity and vitamin 'C' content decreased. Texture and flavour scores as recorded after a week, were not affected by irradiation except in 1.5 kGy. In 'Mosambi' sweet orange, radiation treatments caused peel disorder in the form of brown sunken areas after 90 days and reduced fruit firmness, acidity and vitamin C content. The TSS content was higher in treated fruit. Flavour and texture were not affected by the doses of irradiation used. In treated acid limes (mature yellow), weight loss and decay were higher than untreated fruit (0 kGy) although difference was non-significant. Juice, TSS, titratable acidity and vitamin C contents were significantly less in treated fruit than in 0 kGy. Texture and flavour scores were also less in treated fruit than in 0 kGy. The stem-end rind breakdown was higher in untreated fruit than treated ones although difference was

  13. Novel bentonite clay-based Fe-nanocomposite as a heterogeneous catalyst for photo-Fenton discoloration and mineralization of Orange II.

    Science.gov (United States)

    Feng, Jiyun; Hu, Xijun; Yue, Po Lock

    2004-01-01

    A novel bentonite clay-based Fe-nanocomposite (Fe-B) was successfully developed as a heterogeneous catalyst for photo-Fenton discoloration and mineralization of an azo-dye Orange II. X-ray diffraction (XRD) analysis clearly reveals that the Fe-B nanocomposite catalyst mainly consists of Fe2O3 (hematite) and SiO2 (quartz) crystallites, and the Fe concentration of the Fe-B catalyst determined by X-reflective fluorescence (XRF) is 31.8 wt %. The catalytic activity of the Fe-B was evaluated in the discoloration and mineralization of Orange II in the presence of H2O2 and UVC light (254 nm). It was found that the optimal Fe-B catalyst dosage is around 1.0 g/L, and the efficiency of discoloration and mineralization of Orange II increases as initial Orange II concentration decreases or reaction temperature increases. In addition, at optimal conditions (10 mM H2O2, 1.0 g of Fe-B/L, 1 x 8W UVC, and pH = 3.0), complete discoloration and mineralization of 0.2 mM Orange II can be achieved in less than 60 and 120 min, respectively. The result strongly indicates that the Fe-B nanocomposite catalyst exhibits a high catalytic activity not only in the photo-Fenton discoloration of Orange II but also in the mineralization of Orange II. The reaction kinetics analysis illustrates that the photo-Fenton discoloration of Orange II in the first 15 min obeys the pseudo-first-order kinetics. The reaction activation energy calculated was 9.94 kJ/mol, indicating that the photo-Fenton discoloration of Orange II is not very sensitive to reaction temperature.

  14. Indole-3-Acetic Acid Biosynthesis in the Mutant Maize orange pericarp, a Tryptophan Auxotroph.

    Science.gov (United States)

    Wright, A D; Sampson, M B; Neuffer, M G; Michalczuk, L; Slovin, J P; Cohen, J D

    1991-11-15

    The maize mutant orange pericarp is a tryptophan auxotroph, which results from mutation of two unlinked loci of tryptophan synthase B. This mutant was used to test the hypothesis that tryptophan is the precursor to the plant hormone indole-3-acetic acid (IAA). Total IAA in aseptically grown mutant seedlings was 50 times greater than in normal seedlings. In mutant seedlings grown on media containing stable isotopelabeled precursors, IAA was more enriched than was tryptophan. No incorporation of label into IAA from tryptophan could be detected. These results establish that IAA can be produced de novo without tryptophan as an intermediate.

  15. A Multifunctional Mn(II) Phosphonate for Rapid Separation of Methyl Orange and Electron-Transfer Photochromism.

    Science.gov (United States)

    Gao, Chao-Ying; Yang, Yang; Ai, Jing; Tian, Hong-Rui; Li, Lei-Jiao; Yang, Weiting; Dang, Song; Sun, Zhong-Ming

    2016-08-08

    A Mn(II) phosphonate of the general formula [Mn(H2 L)2 (H2 O)2 (H2 bibp)] adopts a layered motif with protonated H2 bibp(2+) cations embedded in the channels (H4 L=thiophene-2-phosphonic acid; bibp=4,4'-bis(1-imidazolyl)biphenyl). The title compound exhibits excellent adsorptive removal of methyl orange (MO) dye from aqueous solution. Its advantageous features include fast adsorption, high uptake capacity, selective removal, and reusability, which are of great significance for practical application in wastewater treatment. Meanwhile, the compound displays rapid photochromism upon irradiation with visible light at room temperature. Extensive research has demonstrated that such behavior is based on a ligand-to-ligand charge-transfer (LLCT) mechanism. The irradiated sample possesses an ultra-long-lived charge-separated state. Moreover, not only is the compound the first Mn-based photochromic MOF, but it is also one of the very few examples showing LLCT with non-photochromic components. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. The sonochemical decolourisation of textile azo dye Orange II: effects of Fenton type reagents and UV light.

    Science.gov (United States)

    Dükkancı, Meral; Vinatoru, Mircea; Mason, Timothy J

    2014-03-01

    The removal of Orange II (O-II) from aqueous solution under irradiation at 850 kHz has been studied. The effects of both homogeneous (with FeSO4/H2O2), and heterogeneous (Fe containing ZSM-5 zeolite/H2O2) Fenton type reagents are reported together with the effect of UV irradiation in combination with ultrasound both alone and with homogeneous Fenton-type reagent. Degrees of decolourisation of 6.5% and 28.9% were observed using UV radiation and ultrasound, respectively, whereas under the simultaneous irradiation of ultrasound and UV light, the decolourisation degree reached 47.8%, indicating a synergetic effect of ultrasound and UV light. The decolourisation was increased with the addition of Fenton's reagent with an optimal Fenton molar reagent ratio, Fe(2+):H2O2 of 1:50. In the combined process of ultrasound and UV light with the homogeneous Fenton system 80.8% decolourisation could be achieved after 2h indicating that UV improves this type of Orange II degradation. The degree of decolourisation obtained using the heterogeneous sono-Fenton system (Fe containing ZSM-5 zeolite catalysts+H2O2+ultrasound) were consistently lower than the traditional homogeneous ultrasound Fenton system. This can be attributed to the greater difficulty of the reaction between Fe ions and hydrogen peroxide. In all cases the Orange II ultrasonic decolourisation was found to follow first order kinetics.

  17. Influence of orange cultivar and mandarin postharvest storage on polyphenols, ascorbic acid and antioxidant activity during gastrointestinal digestion.

    Science.gov (United States)

    De Ancos, Begoña; Cilla, Antonio; Barberá, Reyes; Sánchez-Moreno, Concepción; Cano, M Pilar

    2017-06-15

    Polyphenols, ascorbic acid content and antioxidant activity of two sweet oranges (Navel-N and Cara Cara-CC) and mandarin (Clementine-M) as well as their bioaccessibilities were evaluated in pulps and compared to those in fresh juice. Thus, pulps of oranges and mandarins displayed higher hesperidin (HES), narirutin (NAR), total flavonoids (TF), total phenols (TP) and antioxidant activity (AAC) than their corresponding juices. Also, CC products presented higher bioactive compounds content than N ones. Bioaccessibility of bioactive compounds and AAC were higher in pulps of both oranges and mandarin than in their corresponding juices. Oranges (N and CC) pulps and juices presented higher bioaccessibilities than mandarin ones. The postharvest storage of mandarin at 12°C during 5weeks not only produced a significant increase of the bioactive compounds but also an increase of their bioaccessibility. The bioaccessibility of Citrus bioactive compounds is necessary for calculating more accurately their daily intake amount.

  18. Femtochemistry of orange II in solution and in chemical and biological nanocavities

    Science.gov (United States)

    Douhal, Abderrazzak; Sanz, Mikel; Tormo, Laura

    2005-01-01

    In this work, we report on studies of the nature of the dynamics and hydrophobic binding in cyclodextrins and human serum albumin protein complexes with orange II. With femtosecond time resolution, we examined the proton-transfer and trans-cis isomerization reactions of the ligand in these nanocavities and in pure solvents. Because of confinement at the ground state, the orientational motion in the formed phototautomer is restricted, leading to a rich dynamics. Therefore, the emission lifetimes span a large window of tens to hundreds of picoseconds in the cavities. Possible H-bond interactions between the guest and cyclodextrin do not affect the caged dynamics. For the protein–ligand complexes, slow diffusional motion (≈630 ps) observed in the anisotropy decay indicates that the binding structure is not completely rigid, and the embedded guest is not frozen with the hydrophobic pocket. The ultrafast isomerization and decays are explained in terms of coupling motions between N–N and C–N stretching modes of the formed tautomer. We discuss the role of confinement on the trans-cis isomerization with the cavities and its relationships to frequency and time domains of nanostructure emission. PMID:16365300

  19. Electrochemical treatment of Orange II dye solution-Use of aluminum sacrificial electrodes and floc characterization

    Energy Technology Data Exchange (ETDEWEB)

    Mollah, M. Yousuf A. [Department of Chemistry, University of Dhaka, Dhaka-1000 (Bangladesh); Gomes, Jewel A.G., E-mail: jewel.gomes@lamar.edu [Dan F. Smith Department of Chemical Engineering, Lamar University, P.O. Box 10053, Beaumont, TX 77710 (United States); Das, Kamol K.; Cocke, David L. [Gill Chair of Chemical Engineering, Lamar University, P.O. Box 10053, Beaumont, TX 77710 (United States)

    2010-02-15

    Electrocoagulation (EC) of Orange II dye in a flow through cell with aluminum as sacrificial electrodes was carried out under varying conditions of dye concentration, current density, flow rate, conductivity, and the initial pH of the solution in order to optimize the operating parameters for maximum benefits. Maximum removal efficiency of 94.5% was obtained at the following conditions: dye concentration = 10 ppm, current density = 160 A/m{sup 2}, initial pH 6.5, conductance = 7.1 mS/cm, flow rate = 350 mL/min, and concentration of added NaCl = 4.0 g/L of dye solution. The EC-floc was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy, and powder X-ray diffraction techniques. The removal mechanism has been proposed that is in compliance with the Pourbaix diagram, solubility curve of aluminum oxides/hydroxides, and physico-chemical properties of the EC-floc.

  20. Electro-assisted heterogeneous activation of persulfate by Fe/SBA-15 for the degradation of Orange II.

    Science.gov (United States)

    Cai, Chun; Zhang, Zhuoyue; Zhang, Hui

    2016-08-05

    The removal of Orange II by activation of persulfate (S2O8(2-), PS) using synthesized Fe/SBA-15 in the electrochemical (EC) enhanced process was reported in this study. The reaction rate constants, degradation mechanism, catalyst stability, and evolution of mineralization and toxicity were detailed investigated. On the basis of radical scavenger results, both the sulfate radicals (SO4(-)) and hydroxyl radicals (OH) were responsible for the degradation of Orange II. A possible pathway is suggested to describe the degradation of Orange II according to the degradation intermediates identified. The results showed that the Fe/SBA-15 catalyst maintained strong reusability and stability with a low level of iron leaching. In addition, favorable mineralization efficiency in terms of COD removal efficiency (75.4%) and TOC removal efficiency (46.3%) was obtained when the reaction time was prolonged to 24h. The toxicity experiments implied that the toxicity of the treated solution ascended at the first 30min but then dropped to almost zero eventually. This study provides a proof-of-concept that can be applied widely for the PS remediation of contaminated water.

  1. Degradation kinetic modelling of ascorbic acid and colour intensity in pasteurised blood orange juice during storage.

    Science.gov (United States)

    Remini, Hocine; Mertz, Christian; Belbahi, Amine; Achir, Nawel; Dornier, Manuel; Madani, Khodir

    2015-04-15

    The stability of ascorbic acid and colour intensity in pasteurised blood orange juice (Citrus sinensis [L.] Osbeck) during one month of storage was investigated at 4-37 °C. The effects of ascorbic acid fortification (at 100, 200 mg L(-1)) and deaeration, temperature/time storage on the kinetic behaviour were determined. Ascorbic acid was monitored by HPLC-DAD and colour intensity by spectrophotometric measurements. Degradation kinetics were best fitted by first-order reaction models for both ascorbic acid and colour intensity. Three models (Arrhenius, Eyring and Ball) were used to assess the temperature-dependent degradation. Following the Arrhenius model, activation energies were ranged from 51 to 135 kJ mol(-1) for ascorbic acid and from 49 to 99 kJ mol(-1) for colour intensity. The effect of storage temperature and deaeration are the most influent factors on kinetics degradation, while the fortification revealed no significant effect on ascorbic acid content and colour intensity.

  2. New insights into the electrochemical behavior of acid orange 7: Convergent paired electrochemical synthesis of new aminonaphthol derivatives

    Science.gov (United States)

    Momeni, Shima; Nematollahi, Davood

    2017-02-01

    Electrochemical behavior of acid orange 7 has been exhaustively studied in aqueous solutions with different pH values, using cyclic voltammetry and constant current coulometry. This study has provided new insights into the mechanistic details, pH dependence and intermediate structure of both electrochemical oxidation and reduction of acid orange 7. Surprisingly, the results indicate that a same redox couple (1-iminonaphthalen-2(1H)-one/1-aminonaphthalen-2-ol) is formed from both oxidation and reduction of acid orange 7. Also, an additional purpose of this work is electrochemical synthesis of three new derivatives of 1-amino-4-(phenylsulfonyl)naphthalen-2-ol (3a–3c) under constant current electrolysis via electrochemical oxidation (and reduction) of acid orange 7 in the presence of arylsulfinic acids as nucleophiles. The results indicate that the electrogenerated 1-iminonaphthalen-2(1 H)-one participates in Michael addition reaction with arylsulfinic acids to form the 1-amino-3-(phenylsulfonyl)naphthalen-2-ol derivatives. The synthesis was carried out in an undivided cell equipped with carbon rods as an anode and cathode.

  3. Preparation and physicochemical properties of soluble dietary fiber from orange peel assisted by steam explosion and dilute acid soaking.

    Science.gov (United States)

    Wang, Lei; Xu, Honggao; Yuan, Fang; Fan, Rui; Gao, Yanxiang

    2015-10-15

    The coupled pretreatment of orange peel with steam explosion (SE) and sulfuric-acid soaking (SAS) was investigated to enhance the yield and improve the functionality of soluble dietary fiber (SDF). When orange peel was pretreated by SE at 0.8MPa for 7 min, combined with 0.8% SAS, the content of SDF was increased from 8.04% to 33.74% in comparison to the control and SDF prepared with SE-SAS showed the high water solubility, water-holding capacity, oil-holding capacity, swelling capacity, emulsifying activity, emulsion stability and foam stability. SDF from orange peel treated by SE-SAS exhibited significantly (p < 0.05) higher binding capacity for three toxic cations (Pb, As and Cu) and smaller molecular weight (Mw = 174 kDa). Furthermore, differential scanning calorimetry (DSC) measurement showed that SDF from orange peel treated by SE-SAS had a higher peak temperature (170.7 ± 0.4 °C) than that of the untreated sample (163.4 ± 0.3 °C). Scanning electron micrograph (SEM) images demonstrated that the surface of SDF from orange peel treated by SE-SAS was rough and collapsed. It can be concluded that SDF from orange peel treated by SE-SAS has the higher potential to be applied as a functional ingredient in food products.

  4. An evaluation of the accuracy of the ORange® (Gen II) by comparing it to the IOLMaster® in the prediction of postoperative refraction

    Science.gov (United States)

    Chen, Ming

    2012-01-01

    Purpose The aim of this study was to evaluate the accuracy of ORange® Gen II (WaveTec Vision, Aliso Viejo, CA). Setting The Surgical Suites, Honolulu, HI. Methods The prospective 28 consecutive cataract surgical cases were selected from 85 cataract surgical cases between December 16, 2010 and February 24, 2011. With the same intraocular lens implantation, the predicted spherical equivalent refraction from IOLMaster® (Carl Zeiss AG, Oberkochen, Germany) and ORange Gen II were statistically compared and verified with 1-month postoperative manifest refraction. The data were put into IBM SPSS 19 (SPSS Inc, Chicago, IL) for analysis of variance. Pearson’s correlation coefficient was also calculated to evaluate the correlation between the IOLMaster, ORange Gen II, and 1-month postoperative manifest refraction. Results There were no statistically significant differences in the mean spherical equivalent refraction from the IOLMaster, ORange Gen II, and 1-month postoperative manifest refraction (IOLMaster −0.40 diopters, P = 0.07; ORange Gen II −0.43 diopters, P = 0.16; 1-month refraction −0.41 diopters, P = 0.07). Pearson’s correlation study demonstrated that all three were positively correlated (P refraction (r = +0.6, P < 0.01). Conclusion The ORange Gen II can be considered as an alternative method for intraocular lens selection for cataract patients. PMID:22457590

  5. An evaluation of the accuracy of the ORange (Gen II) by comparing it to the IOLMaster in the prediction of postoperative refraction.

    Science.gov (United States)

    Chen, Ming

    2012-01-01

    The aim of this study was to evaluate the accuracy of ORange(®) Gen II (WaveTec Vision, Aliso Viejo, CA). The Surgical Suites, Honolulu, HI. The prospective 28 consecutive cataract surgical cases were selected from 85 cataract surgical cases between December 16, 2010 and February 24, 2011. With the same intraocular lens implantation, the predicted spherical equivalent refraction from IOLMaster(®) (Carl Zeiss AG, Oberkochen, Germany) and ORange Gen II were statistically compared and verified with 1-month postoperative manifest refraction. The data were put into IBM SPSS 19 (SPSS Inc, Chicago, IL) for analysis of variance. Pearson's correlation coefficient was also calculated to evaluate the correlation between the IOLMaster, ORange Gen II, and 1-month postoperative manifest refraction. There were no statistically significant differences in the mean spherical equivalent refraction from the IOLMaster, ORange Gen II, and 1-month postoperative manifest refraction (IOLMaster -0.40 diopters, P = 0.07; ORange Gen II -0.43 diopters, P = 0.16; 1-month refraction -0.41 diopters, P = 0.07). Pearson's correlation study demonstrated that all three were positively correlated (P refraction (r = +0.6, P < 0.01). The ORange Gen II can be considered as an alternative method for intraocular lens selection for cataract patients.

  6. Pleurotus ostreatus manganese-dependent peroxidase silencing impairs decolourization of Orange II.

    Science.gov (United States)

    Salame, Tomer M; Yarden, Oded; Hadar, Yitzhak

    2010-01-01

    Decolourization of azo dyes by Pleurotus ostreatus, a white-rot fungus capable of lignin depolymerization and mineralization, is related to the ligninolytic activity of enzymes produced by this fungus. The capacity of P. ostreatus to decolourize the azo dye Orange II (OII) was dependent and positively co-linear to Mn(2+) concentration in the medium, and thus attributed to Mn(2+)-dependent peroxidase (MnP) activity. Based on the ongoing P. ostreatus genome deciphering project we identified at least nine genes encoding for MnP gene family members (mnp 1-9), of which only four (mnp 1-4) were previously known. Relative real-time PCR quantification analysis confirmed that all the nine genes are transcribed, and that Mn(2+) amendment results in a drastic increase in the transcript levels of the predominantly expressed MnP genes (mnp 3 and mnp 9), while decreasing versatile peroxidase gene transcription (mnp 4). A reverse genetics strategy based on silencing the P. ostreatus mnp 3 gene by RNAi was implemented. Knock-down of mnp 3 resulted in the reduction of fungal OII decolourization capacity, which was co-linear with marked silencing of the Mn(2+)-dependent peroxidase genes mnp 3 and mnp 9. This is the first direct genetic proof of an association between MnP gene expression levels and azo dye decolourization capacity in P. ostreatus, which may have significant implication on understanding the mechanisms governing lignin biodegradation. Moreover, this study has proven the applicability of RNAi as a tool for gene function studies in Pleurotus research.

  7. Pleurotus ostreatus manganese‐dependent peroxidase silencing impairs decolourization of Orange II

    Science.gov (United States)

    Salame, Tomer M.; Yarden, Oded; Hadar, Yitzhak

    2010-01-01

    Summary Decolourization of azo dyes by Pleurotus ostreatus, a white‐rot fungus capable of lignin depolymerization and mineralization, is related to the ligninolytic activity of enzymes produced by this fungus. The capacity of P. ostreatus to decolourize the azo dye Orange II (OII) was dependent and positively co‐linear to Mn2+ concentration in the medium, and thus attributed to Mn2+‐dependent peroxidase (MnP) activity. Based on the ongoing P. ostreatus genome deciphering project we identified at least nine genes encoding for MnP gene family members (mnp1–9), of which only four (mnp1–4) were previously known. Relative real‐time PCR quantification analysis confirmed that all the nine genes are transcribed, and that Mn2+ amendment results in a drastic increase in the transcript levels of the predominantly expressed MnP genes (mnp3 and mnp9), while decreasing versatile peroxidase gene transcription (mnp4). A reverse genetics strategy based on silencing the P. ostreatus mnp3 gene by RNAi was implemented. Knock‐down of mnp3 resulted in the reduction of fungal OII decolourization capacity, which was co‐linear with marked silencing of the Mn2+‐dependent peroxidase genes mnp3 and mnp9. This is the first direct genetic proof of an association between MnP gene expression levels and azo dye decolourization capacity in P. ostreatus, which may have significant implication on understanding the mechanisms governing lignin biodegradation. Moreover, this study has proven the applicability of RNAi as a tool for gene function studies in Pleurotus research. PMID:21255310

  8. Integrated systems biology analysis of transcriptomes reveals candidate genes for acidity control in developing fruits of sweet orange (Citrus sinensis L. Osbeck

    Directory of Open Access Journals (Sweden)

    Dingquan eHuang

    2016-04-01

    Full Text Available Organic acids, such as citrate and malate, are important contributors for the sensory traits of fleshy fruits. Although their biosynthesis has been illustrated, regulatory mechanisms of acid accumulation remain to be dissected. To provide transcriptional architecture and identify candidate genes for citrate accumulation in fruits, we have selected for transcriptome analysis four varieties of sweet orange (Citrus sinensis L. Osbeck with varying fruit acidity, Succari (acidless, Bingtang (low acid, and Newhall and Xinhui (normal acid. Fruits of these varieties at 45 days post anthesis (DPA, which corresponds to Stage I (cell division, had similar acidity, but they displayed differential acid accumulation at 142 DPA (Stage II, cell expansion. Transcriptomes of fruits at 45 and 142 DPA were profiled using RNA sequencing and analyzed with three different algorithms (Pearson correlation, gene coexpression network and surrogate variable analysis. Our network analysis shows that the acid-correlated genes belong to three distinct network modules. Several of these candidate fruit acidity genes encode regulatory proteins involved in transport (such as AH10, degradation (such as APD2 and transcription (such as AIL6 and act as hubs in the citrate accumulation gene networks. Taken together, our integrated systems biology analysis has provided new insights into the fruit citrate accumulation gene network and led to the identification of candidate genes likely associated with the fruit acidity control.

  9. Electroanalytical method for determination of lead(II) in orange and apple using kaolin modified platinum electrode.

    Science.gov (United States)

    El Mhammedi, M A; Achak, M; Bakasse, M; Chtaini, A

    2009-08-01

    This paper reports on the use of platinum electrode modified with kaolin (K/Pt) and square wave voltammetry for analytical detection of trace lead(II) in pure water, orange and apple samples. The electroanalytical procedure for determination of the Pb(II) comprises two steps: the chemical accumulation of the analyte under open-circuit conditions followed by the electrochemical detection of the preconcentrated species using square wave voltammetry. The analytical performances of the extraction method has been explored by studying the incubating time, and effect of interferences due to other ions. During the preconcentration step, Pb(II) was accumulated on the surface of the kaolin. The observed detection and quantification limits in pure water were 3.6x10(-9)molL(-1) and 1.2x10(-8)molL(-1), respectively. The precision of the method was also determined; the results was 2.35% (n=5).

  10. Synthesis of Magnetically Modified Fe-Al Pillared Bentonite and Heterogeneous Fenton-like Degradation of Orange II

    Institute of Scientific and Technical Information of China (English)

    CHEN Kun; WANG Guanghua; LI Wenbing; WAN Dong; HU Qin; LU Lulu; WEI Xiaobi; CHENG Zhengzai

    2015-01-01

    Magnetically modified Fe-Al pillared bentonite (Fe3O4/ Fe-Al-Bent) was prepared via chemical co-precipitation method and characterized by powder X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). A series of experiments were carried out to investigate the degradation of Orange II by the obtained heterogeneous catalysts in the presence of H2O2. The experimental result indicated that the synthetic materials had a high catalytic activity and good reusability.

  11. Discoloration and mineralization of Orange II by using a bentonite clay-based Fe nanocomposite film as a heterogeneous photo-Fenton catalyst.

    Science.gov (United States)

    Feng, Jiyun; Hu, Xijun; Yue, Po Lock

    2005-01-01

    Discoloration and mineralization of an azo dye Orange II was conducted by using a bentonite clay-based Fe nanocomposite (Fe-B) film as a heterogeneous photo-Fenton catalyst in the presence of UVC light and H(2)O(2). Under optimal conditions (pH=3.0, 10 mM H(2)O(2), and 1 x 8W UVC), 100% discoloration and 50-60% TOC removal of 0.2 mM Orange II can be achieved in 90 and 120 min, respectively. The mineralization kinetics of 0.2 mM Orange II is much slower than the corresponding discoloration kinetics. Under the same conditions, the Fe leaching from the Fe-B-coated catalyst film is very low. The Fe-B-coated catalyst film could be used in the pre-treatment of wastewater for an integrated system consisting of a photochemical reactor and a biological reactor. Multi-run experimental results reveal that the Fe-B-coated catalyst film could have a long-term stability for the discoloration and mineralization of Orange II. A comparison between the performance of the Fe-B-coated catalyst film and a suspended Fe-B catalyst in the discoloration and mineralization of Orange II was also discussed.

  12. Electrochemical degradation applied to the metabolites of Acid Orange 7 anaerobic biotreatment.

    Science.gov (United States)

    Carvalho, C; Fernandes, A; Lopes, A; Pinheiro, H; Gonçalves, I

    2007-04-01

    The electrochemical oxidation of the biotic degradation products of the textile dye C.I. Acid Orange 7 (AO7) was achieved using a boron doped diamond electrode (BDD). Tests were performed with model solutions of the biotic degradation products, sulphanilic acid (SA) and 1-amino-2-naphthol (AN), and also with real effluents obtained in experiments carried out in an up-flow anaerobic sludge blanket (UASB) reactor, fed with a simulated textile effluent containing AO7, working in mesophilic or thermophilic conditions. Bulk electrolysis was studied using two different supporting electrolytes - NaCl and Na(2)SO(4). The influence of initial metabolite concentration and current density on the electrodegradation rates of the biotic products was investigated. For the UASB effluents, oxidation tests were carried out for different electrolytes and at different current densities. Samples were collected at pre-selected intervals and absorbance measurements, chemical oxygen demand (COD) and total organic carbon (TOC) tests and high performance liquid chromatography (HPLC) analysis were performed. Results have shown an almost complete elimination of the persistent pollutants and a COD removal higher than 70% for both AN and SA. For the UASB effluents, COD removals between 45% and 90% and TOC removals varying from 19% to 41% were obtained.

  13. Degradation of Acid Orange 7 in an Atmospheric-Pressure Plasma-Solution System (Gliding Discharge)

    Science.gov (United States)

    NI, Mingjiang; YANG, Huan; CHEN, Tong; ZHANG, Hao; WU, Angjian; DU, Changming; LI, Xiaodong

    2015-03-01

    In this work, a plasma-solution system was applied to the degradation of Acid Orange 7 (AO7). The effects of initial concentration and type of feed gases (air, oxygen, nitrogen or argon) were studied. As the initial concentration increased from 100 mg/L to 160 mg/L, the discolouration rate of AO7 decreased from 99.3% to 95.9%, whereas the COD removal rate decreased from 37.9% to 22.6%. Air provided the best discolouration and COD removal rates (99.3% and 37.9%, respectively). In the presence of a zero-valent iron (ZVI) catalyst, the AO7 COD removal rate increased to 76.4%. The degradation products were analysed by a GC-MS, revealing that the degradation of the dye molecule was initiated through the cleavage of the -N=N- bond before finally being converted to organic acids. supported by National Natural Science Foundation of China (Nos. 50908237, 51076142) and the Open Foundation of the State Key Laboratory of Clean Energy Utilization of China (No. ZJUCEU2009008)

  14. Adsorption of Acid Orange 8 Dye from Aqueous Solution Onto Unmodified and Modified Zeolites

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    Tharcila Colachite Rodrigues Bertolini

    2015-12-01

    Full Text Available The adsorption of the acid dye Acid Orange 8 (AO8 onto unmodified and modified zeolites from coal fly ash and bottom ash was evaluated. The coal fly ash and bottom ash used in the synthesis of the zeolites by alkaline hydrothermal treatment were collected in the Thermoelectric Complex Jorge Lacerda, located in the Santa Catarina State, Brazil, the largest coal burning thermoelectric complex of Latin America. The modified zeolites were modified using the surfactant hexadecyltrimethylammonium bromide. The zeolitic materials were characterized predominantly as hydroxysodalite and NaX. The kinetics studies indicated that the adsorption followed the pseudo-second order kinetics. Linear and non-linear regression methods were used to determine the best fit of equilibrium data. The Freundlich model was better adjusted to the experimental data for all systems studied. The parameters of adsorption isotherms were used to predict the design of the equipment for performing adsorption discontinuous single stage. DOI: http://dx.doi.org/10.17807/orbital.v7i4.764 

  15. [Degradation of Acid Orange 7 with Persulfate Activated by Silver Loaded Granular Activated Carbon].

    Science.gov (United States)

    Wang, Zhong-ming; Huang, Tian-yin; Chen, Jia-bin; Li, Wen-wei; Zhang, Li-ming

    2015-11-01

    Granular activated carbon with silver loaded as activator (Ag/GAC) was prepared using impregnation method. N2 adsorption, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) were adopted to characterize the Ag/GAC, showing that silver was successfully loaded on granular activated carbon. The oxidation degradation of acid orange 7 (AO7) by the Ag/GAC activated by persulfate (PS) was investigated at ambient temperature. The influences of factors such as Ag loading, PS or Ag/GAC dosages and initial pH on the degradation of AO7 were evaluated. The results demonstrated that the degradation rate of AO7 could reach more than 95.0% after 180 min when the Ag loading content, PS/AO7 molar ratio, the Ag/GAC dosage were 12.7 mg x g(-1), 120: 1, 1.0 g x L(-1), respectively. The initial pH had significant effect on the AO7 degradation, with pH 5.0 as the optimal pH for the degradation of AO7. The possible degradation pathway was proposed for the AO7 degradation by using UV-visible spectroscopy and gas chromatography-mass spectrometry (GG/MS). The azo bond and naphthalene ring in the AO7 were destroyed during the degradation, with phthalic acid and acetophenone as the main degradation products.

  16. In vitro study of DNA damage induced by acid orange 52 and its biodegradation derivatives.

    Science.gov (United States)

    Ben Mansour, Hedi; Barillier, Daniel; Corroler, David; Ghedira, Kamel; Chekir-Ghedira, Leila; Mosrati, Ridha

    2009-03-01

    Mutagenicity of acid orange 52 (AO52) and its degradation products by Pseudomonas putida mt-2 was evaluated with the use of Salmonella Typhimurium TA102 and TA104 with and without the metabolic activation system (S9). No mutagenicity was observed in the absence of S9 and in the presence of S9 for biodegradation under shaking conditions, but it increased significantly in the presence of S9 after biodegradation under static conditions. In addition, the ability of tested compounds to induce DNA damage in vitro was evaluated with the DNA strand scission assay. The toxicity generated by the pure azo dye and the corresponding azoreduction products (4-aminobenzenesulfonic acid and N,N'-dimethyl-p-phenylenediamine) were compared. We suggest that the mutagenicity mechanism of these molecules occurs through free radical generation processes. In this study, we demonstrate that P. putida mt-2 incubated under aerobic conditions undergoes catabolism that enables it to degrade AO52 completely and, especially, to detoxify the dye mixtures.

  17. Microwave-assisted degradation of acid orange using a conjugated polymer, polyaniline, as catalyst

    Directory of Open Access Journals (Sweden)

    Ufana Riaz

    2014-01-01

    Full Text Available Microwave-assisted photocatalytic degradation of dyes is one of the emerging technologies for waste water remediation. Microwave effectively accelerates photocatalytic degradation, when microwave electrodeless lamp (MEL substitutes traditional UV lamp as light source. This setup can be extremely simplified if MEL and photocatalyst can be replaced by a catalyst which can work under microwave irradiation in the absence of any light source. The present work reports for the first time degradation of acid orange 7 (AO under microwave irradiation using polyaniline (PANI as catalyst in the absence of any UV lamp as light source. The degradation/decolourization was carried out in neutral acidic and basic media and was monitored spectrophotometrically to evaluate the ability of microwave irradiation to degrade AO. Microwave irradiation showed excellent performance as it completely decolourizes AO dye solution in 10 min. With the advantages of low cost and rapid processing, this novel catalyst is expected to gain promising application in the treatment of various dyestuff wastewaters on a large scale.

  18. Catalytic degradation of Acid Orange 7 by manganese oxide octahedral molecular sieves with peroxymonosulfate under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Lian; Sun, Binzhe; Wei, Mingyu; Luo, Shilu; Pan, Fei; Xu, Aihua [School of Environmental Engineering, Wuhan Textile University, Wuhan 430073 (China); Li, Xiaoxia, E-mail: lixxwh@163.com [School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430073 (China)

    2015-03-21

    Highlights: • OMS-2/PMS/Vis system could efficiently catalyze the degradation of organic dyes. • The system showed much higher activity than that of OMS-2/PMS and OMS-2/Vis. • The OMS-2 catalyst exhibited stable performance for multiple runs. • Sulfate radicals were suggested to be the major reactive species in the system. • The radicals production might involve the redox cycle of Mn(IV)/Mn(III) and Mn(III)/Mn(II). - Abstract: In this paper, the photodegradation of Acid Orange 7 (AO7) in aqueous solutions with peroxymonosulfate (PMS) was studied with manganese oxide octahedral molecular sieves (OMS-2) as the catalyst. The activities of different systems including OMS-2 under visible light irradiation (OMS-2/Vis), OMS-2/PMS and OMS-2/PMS/Vis were evaluated. It was found that the efficiency of OMS-2/PMS was much higher than that of OMS-2/Vis and could be further enhanced by visible light irradiation. The catalyst also exhibited stable performance for multiple runs. Results from ESR and XPS analyses suggested that the highly catalytic activity of the OMS-2/PMS/Vis system possible involved the activation of PMS to sulfate radicals meditated by the redox pair of Mn(IV)/Mn(III) and Mn(III)/Mn(II), while in the OMS-2/PMS system, only the redox reaction between Mn(IV)/Mn(III) occurred. Several operational parameters, such as dye concentration, catalyst load, PMS concentration and solution pH, affected the degradation of AO7.

  19. Adsorption of Orange II dye in aqueous solution onto surfactant-coated zeolite: characterization, kinetic and thermodynamic studies.

    Science.gov (United States)

    Jin, Xiaoying; Yu, Bing; Chen, Zuliang; Arocena, Joselito M; Thring, Ronald W

    2014-12-01

    Adsorption of anionic dye - Orange II - in aqueous solution onto hexadecyltrimethylammonium bromide (HDTMA)-coated zeolite (HCZ) reached 38.96mg/g compared with 8.13mg/g onto natural zeolite. Fourier Transform Infrared (FTIR), scanning electronic microscopy (SEM) and X-ray powder diffraction (XRD) data showed that HDTMA-coated zeolite developed surficial positive charges. The adsorption reaction fits the Freundlich isotherm (R(2)=0.93) and the value of 1/n was less than unity (=0.81) and suggest a multi-layer physi-sorption process. The kinetics of the adsorption is a pseudo-second-order model. The activation energy (Ea) of the reaction is +35.70kJ/mol to further support a physi-sorption process while the ΔH(o) (+82.79kJ/mol) is characteristic for an endothermic reaction. The ΔG(o) values of -2.33, -0.98 and -0.37kJ/mol at 25°C, 30°C and 35°C, respectively implied that the adsorption reaction was feasible and thermodynamically spontaneous. We proposed that both electrostatic interactions and partitioning process are involved in the adsorption mechanisms of Orange II dye onto HCZ. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Biochemical characterization of blood orange, sweet orange, lemon, bergamot and bitter orange.

    Science.gov (United States)

    Moufida, Saïdani; Marzouk, Brahim

    2003-04-01

    This paper reports on the composition of aroma compounds and fatty acids and some physico-chemical parameters (juice percentage, acidity and total sugars) in five varieties of citrus: blood orange, sweet orange, lemon, bergamot and bitter orange. Volatile compounds and methyl esters have been analyzed by gas chromatography. Limonene is the most abundant compound of monoterpene hydrocarbons for all of the examined juices. Eighteen fatty acids have been identified in the studied citrus juices, their quantification points out that unsaturated acids predominate over the saturated ones. Mean concentration of fatty acids varies from 311.8 mg/l in blood orange juice to 678 mg/l in bitter orange juice.

  1. Removal of azo dye acid orange 7 using aerobic membrane bioreactor

    Directory of Open Access Journals (Sweden)

    A.H. Konsowa

    2011-03-01

    Full Text Available A laboratory scale aerobic membrane bioreactor (MBR using a submerged microfiltration (MF; hollow-fiber membrane was used for treating wastewater polluted with azo dye acid orange 7 (AO7. Initial dye concentrations studied were from 50 to 400 mg/l with a COD ranging from 95 to 550 mg O2/l and hydraulic retention times (HRT 4, 6, 8 and 24 h. Results showed that the biological process was responsible for almost 60–80% of COD removal and almost all the removal of AO7 color. Membrane microfiltration merely balanced the unstable biological treatment of COD and demonstrated almost no contribution to AO7 color removal. Trans-membrane pressure (TMP increased with time, and with the increase of dye concentration reaching a maximum of 4.175 psi. Scanning electron microscope (SEM images of the membrane’s filament were taken and compared with a SEM image of a virgin membrane; clear deformation in membrane’s pore structure could be noticed as well as scale formation on the outer surface of filaments, foulants were determined using the energy dispersive X-ray analysis (EDX.

  2. Chromate enhanced visible light driven TiO₂ photocatalytic mechanism on Acid Orange 7 photodegradation.

    Science.gov (United States)

    Wang, Yeoung-Sheng; Shen, Jyun-Hong; Horng, Jao-Jia

    2014-06-15

    When hexavalent chromium (Cr(VI)) is added to a TiO2 photocatalytic reaction, the decolorization and mineralization efficiencies of azo dyes Acid Orange 7 (AO7) are enhanced even though the mechanism is unclear. This study used 5,5-dimethyl-l-pyrroline-N-oxide (DMPO) as the scavenger and the analysis of Electron Spin Resonance (ESR) to investigate this enhancement effect by observing the hydroxyl radical (OH) generation of the Cr(VI)/TiO2 system under UV and visible light (Vis) irradiation. With Cr(VI), the decolorization efficiencies were approximately 95% and 62% under UV and Vis, and those efficiencies were 25% less in the absence of Cr(VI). The phenomena of the DMPO-OH signals during the ESR analysis under Vis 405 and 550 nm irradiation were obviously the enhancement effects of Cr(VI) in aerobic conditions. In anoxic conditions, the catalytic effects of Cr(VI) could not be achieved due to the lack of a redox reaction between Cr(VI) and the adsorbed oxygen at the oxygen vacancy sites on the TiO2 surfaces. The results suggest that by introducing the agents of redox reactions such as chromate ions, we could lower the photoenergy of TiO2 needed and allow Vis irradiation to activate photocatalysis.

  3. Mechanistic Study of Adsorption of Acid Orange-7 over Aluminum Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ekta Khosla

    2013-01-01

    Full Text Available The adsorption behavior of acid orange-7 (AO-7 on aluminum oxide nanoparticles (ANP generated by sol-gel method has been investigated to understand the physicochemical process involved and to explore the potential use of nano particles in textile effluent treatment and management. The results revealed that ANP can remove AO-7 dye up to 97.6 mg/g at 303 K. The adsorption process is found to be pH dependent and the optimum pH obtained is 2.0. The equilibrium was established in 1 h. Langmuir, Freundlich, and Temkin Isotherm models were applied on the system. Scanning electron microscopic analysis reveals eye-catching nanoporous morphology of the material. The results of FTIR spectroscopy reveal that the process is electrostatic complexation mechanism driven. XRD studies revealed nanocrystalline structure of ANP. BET surface area measurement suggests high pore volume and surface area of adsorbent. The kinetic measurements suggest pseudo-second-order kinetic processes. The thermodynamic measurements suggest that all processes are endothermic accompanied with negative ΔG° and positive ΔS°, ΔH°.

  4. Activated carbon catalyzed persulfate oxidation of Azo dye acid orange 7 at ambient temperature.

    Science.gov (United States)

    Yang, Shiying; Yang, Xin; Shao, Xueting; Niu, Rui; Wang, Leilei

    2011-02-15

    Persulfate (PS) oxidative degradation of azo dye acid orange 7 (AO7) in an aqueous solution was studied in the presence of suspended granular activated carbon (GAC) at ambient temperature (e.g., 25°C). It was observed that there existed a remarkable synergistic effect in the GAC/PS combined system. Higher PS concentration and GAC dosage resulted in higher AO7 degrading rates. Near-neutral was the optimal initial pH. Adsorption had an adverse effect on AO7 degradation. AO7 had not only a good decolorization, but a good mineralization. The decomposition of PS followed a first-order kinetics behavior both in the presence and in the absence of AO7. Radical mechanism was studied and three radical scavengers (methanol (MA), tert-butanol (TBA), phenol) were used to determine the kind of major active species taking part in the degradation of AO7 and the location of degradation reaction. It was assumed that the degradation of AO7 did not occur in the liquid phase, but in the porous bulk and boundary layer on the external surface of GAC. SO(4)(-•) or HO•, generated on or near the surface of GAC, played a major role in the AO7 degradation. Finally, the recovery performance of GAC was studied through the GAC reuse experiments.

  5. Modified ferrous ammonium sulfate benzoic acid xyelenol orange (MFBX) and thermoluminescent dosimeters--a comparative study.

    Science.gov (United States)

    Brindha, S; Rose, J V R; Sathyan, S; Singh I, Rabi Raja; Ravindran, B Paul

    2002-06-07

    Radiation dosimetry deals with the determination of absorbed dose to the medium exposed to ionizing radiation. Chemical dosimetry depends on oxidation or reduction of chemicals by ionizing radiation. A ferrous ammonium sulfate benzoic acid xyelenol orange (FBX) dosimeter based on this principle is being used as a clinical dosimeter at present. Certain modifications were carried out in the preparation and storage of the FBX dosimeter to increase its shelf life. The resulting dosimeter was called a modified FBX (MFBX) dosimeter and has been used in our department for the past few years. An extensive study of the dose, dose rate and energy response of the dosimeter was carried out and compared with a thermoluminescent (LiF7) dosimeter. The results obtained were found to be comparable to the thermoluminescent (LiF7) dosimeter. Hence it was concluded that the MFBX dosimeter could be used for phantom dosimetry, data collection and in vivo measurements. Easier preparation and availability of the reagents are added advantages of using MFBX as a clinical dosimeter in small radiotherapy departments.

  6. Linear sweep polarographic determination of nucleic acids using acridine orange as a bioprobe

    Directory of Open Access Journals (Sweden)

    WEI SUN

    2007-11-01

    Full Text Available The interaction of acridine orange (AO with double-stranded (ds DNA in aqueous solution was investigated by linear sweep polarography (LSP on a dropping mercury working electrode (DME. In pH 2.5 Britton–Robinson (B–R buffer solution, AO had a sensitive linear sweep polarographic reductive peak at –0.89 V (vs. SCE, which could be greatly inhibited by the addition of dsDNA, with a positive shift of the peak potential. Based on the decrease of the reductive peak current, a new quantitative electrochemical determination method for dsDNA was developed with a linear range of 2.0−20.0 mg l-1 and the linear regression equation: ΔIp” (nA = 111.90 C (mg l-1+125.32 (n = 9, γ = 0.997. The influences of commonly co-existing substances, such as metal ions, amino acid, etc., on the determination were also investigated. The method is sensitive, rapid and simple with good selectivity. The new proposed method was further applied to the detection of RNA and three synthetic samples containing dsDNA with satisfactory results. The binding number and the equilibrium constant between dsDNA and AO were calculated by an electrochemical method.

  7. Efficient photocatalytic degradation of acid orange 7 on metal oxide p-n junction composites under visible light

    Science.gov (United States)

    Suk Jang, Jum; Gyu Kim, Hyun; Lee, Se-Hee

    2012-11-01

    MO(=CuO, Co3O4, NiO)/BiVO4 p-n junction composites were synthesized by urea-precipitation and wet impregnation method. The physicochemical and optical properties of the as-prepared materials were investigated by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-visible diffuse reflectance spectra. The photocatalytic performance of the as-prepared materials was investigated for decomposition of azo dye, acid orange 7. The CuO/BiVO4 and Co3O4/BiVO4 p-n junction composite photocatalysts exhibited the higher photocatalytic degradation of acid orange 7 than those of BiVO4 and NiO/BiVO4 as-prepared samples under visible light irradiation. We also discussed the mechanism of enhanced photocatalytic activity of p-n junctioned composites based on their energy band structures.

  8. Application of Modified Red Mud for Adsorption of Acid Orange 7 (AO7 Dye from Aqueous Solution: Isotherms, Kinetics Studies

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Zazouli

    2015-09-01

    Full Text Available Application of modified red mud for adsorption of Acid Orang 7 (AO7 dye from aqueous solution: Isotherms, Kinetics studies Abstract: Backgroud: Existence of color is one of the problems of industrial effluent such as textile industries. The dyes can be removed by various methods. Therefore, the aim of this study is evaluation of adsorption rate of acid orange (AO7 from aqueous solution by activated red mud. Material and method: This is an empirical lab study. Red mud was used as an absorbent to remove of acid orange 7 dye. The effect of various parameters on performance of absorbent was investigated and the isotherms and kinetics of adsorption was determined. The dye concentration was measured in wavelength of 452 nm by spectrophotometer. Results: The results showed that red mud surface area is 30 m2/g. The results showed that dye removal was highest at a solution pH 3 and a powder dose of 12 g/L. The AO7 removal percentage decreased from %98 to %55 at 60 min contact time when the concentration of dye was increased from 10 mg/L to 100 mg/L. The equilibrium data is best fitted on Langmuir isotherm and the adsorption kinetic model follows pseudo-second model. conclusion: The results of this study showed that red mud is able to adsorption of dye and can be used as effective and inexpensive absorbent to treat of textile effluent.

  9. Involvements of chloride ion in decolorization of Acid Orange 7 by activated peroxydisulfate or peroxymonosulfate oxidation

    Institute of Scientific and Technical Information of China (English)

    Ping Wang; Shiying Yang; Liang Shan; Rui Niu; Xueting Shao

    2011-01-01

    The effects of chloride anion (C1-) (up to 1.0 mol/L) on the decolorization of a model compound,azo dye Acid Orange 7 (AO7),by sulfate radical (SO4-*) based-peroxydisulfate (PS) or peroxymonosulfate (PMS) oxidation under various activated conditions (UV254 nm/PS,Thermal (70℃/PS,UV254 nm/PMS,Co2+/PMS) were investigated.Methanol and NH4+ were used as quenching reagents to determine the contributions of active chlorine species (dichloride radical (Cl2-*) and hypochlorous acid (HClO)).The results indicated that the effects of Cl- on the reaction mechanism were different under various activated conditions.For UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl-concentration increased,probably due to the reaction between Cl- and SO4-* and the generation of Cl2-* or HClO.For UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/L.As Cl-concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with C1- to form HC1O.For Co2+/PMS,Cl- exhibited a significant inhibiting effect even at low concentration (≤ 0.01 mol/L).When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co2+ was almost completely inhibited.Under this condition,HClO maybe played a major role in decolorization of AO7.The results implicated that chloride ion is an important factor in SO4-*-based degradation of organic contamination in chloride-containing water.

  10. Degradation of Acid Orange 7 Dye in Two Hybrid Plasma Discharge Reactors

    Institute of Scientific and Technical Information of China (English)

    SHEN Yongjun; LEI Lecheng; ZHANG Xingwang; DING Jiandong

    2014-01-01

    To get an optimized pulsed electrical plasma discharge reactor and to increase the energy utilization efficiency in the removal of pollutants,two hybrid plasma discharge reactors were designed and optimized.The reactors were compared via the discharge characteristics,energy transfer efficiency,the yields of the active species and the energy utilization in dye wastewater degradation.The results showed that under the same AC input power,the characteristics of the discharge waveform of the point-to-plate reactor were better.Under the same AC input power,the two reactors both had almost the same peak voltage of 22 kV.The peak current of the point-to-plate reactor was 146 A,while that of the wire-to-cylinder reactor was only 48.8 A.The peak powers of the point-to-plate reactor and the wire-to-cylinder reactor were 1.38 MW and 1.01 MW,respectively.The energy per pulse of the point-to-plate reactor was 0.2221 J,which was about 29.4% higher than that of the wire-to-cylinder reactor (0.1716 J).To remove 50% Acid Orange 7 (AO7),the energy utilizations of the point-to-plate reactor and the wireto-cylinder reactor were 1.02×10-9 mol/L and 0.61×10-9 mol/L,respectively.In the point-to-plate reactor,the concentration of hydrogen peroxide in pure water was 3.6 mmol/L after 40 min of discharge,which was higher than that of the wire-to-cylinder reactor (2.5 mmol/L).The concentration of liquid phase ozone in the point-to-plate reactor (5.7×10-2 mmol/L) was about 26.7% higher than that in the wire-to-cylinder reactor (4.5× 10-2 mmol/L).The analysis results of the variance showed that the type of reactor and reaction time had significant impacts on the yields of the hydrogen peroxide and ozone.The main degradation intermediates of AO7 identified by gas chromatography and mass spectrometry (GCMS) were acetic acid,maleic anhydride,pbenzoquinone,phenol,benzoic acid,phthalic anhydride,coumarin and 2-naphthol.Proposed degradation pathways were elucidated in light of the analyzed

  11. Preparation of a novel pH optical sensor using orange (II) based on agarose membrane as support.

    Science.gov (United States)

    Heydari, Rouhollah; Hosseini, Mohammad; Amraei, Ahmadreza; Mohammadzadeh, Ali

    2016-04-01

    A novel and cost effective optical pH sensor was prepared using covalent immobilization of orange (II) indicator on the agarose membrane as solid support. The fabricated optical sensor was fixed into a sample holder of a spectrophotometer instrument for pH monitoring. Variables affecting sensor performance including pH of dye bonding to agarose membrane and dye concentration were optimized. The sensor responds to the pH changes in the range of 3.0-10.0 with a response time of 2.0 min and appropriate reproducibility (RSD ≤ 0.9%). No significant variation was observed on sensor response after increasing the ionic strength in the range of 0.0-0.5M of sodium chloride. Determination of pH using the proposed optical sensor is quick, simple, inexpensive, selective and sensitive in the pH range of 3.0-10.0.

  12. Excellent performance of cobalt-impregnated activated carbon in peroxymonosulfate activation for acid orange 7 oxidation.

    Science.gov (United States)

    Huang, Tianyin; Chen, Jiabin; Wang, Zhongming; Guo, Xin; Crittenden, John C

    2017-03-01

    Cobalt-impregnated activated carbon (GAC/Co) was used to produce sulfate radical (SO4(·-)) from peroxymonosulfate (PMS) in aqueous solution (hereafter called PMS activation). We evaluated its effectiveness by examining the degradation of orange acid 7 (AO7). GAC/Co exhibited high activity to activate PMS to degrade AO7. The degradation efficiency of AO7 increased with increasing dosage of GAC/Co or PMS and elevated temperatures. pH 8 was most favorable for the degradation of AO7 by GAC/Co-activated PMS. The radical quenching experiments indicated that the reactions most likely took place both in the bulk solution and on the surface of GAC/Co. We found that SO4(·-) played a dominant role in AO7 degradation. Sodium chloride (NaCl) which presents in most dye wastewater had a significant impact on AO7 degradation. Low dosages (dosages (0.8 M) increased the reaction rate. HOCl was confirmed as the main contributor for accelerating AO7 degradation with high concentration of NaCl. In a continuous-flow reaction with an empty-bed contact time of 1.35 min, AO7 was not detected in the effluent for 0 to 18.72 L of treated influent volume (156 h) and 85% removal efficiency was still observed after 40.32 L of treated volume (336 h). Finally, the azo bond and the naphthalene structure in AO7 were destroyed and the degradation pathway was proposed.

  13. Treatment of azo dye Acid Orange 52 using ozonation and completed-mixed activated sludge process

    Science.gov (United States)

    Abidin, C. Z. A.; Fahmi; Ong, S. A.; Ahmad, R.; Sabri, S. N.

    2017-06-01

    In this study, the characteristic of colour and COD removal of azo dye Acid Orange 52 (AO52) by ozonation, in combination with complete-mixed activated sludge process (CMAS) was evaluated. The experimentation was arranged in two phases: during the first one, only ozonation was performed, while, during the second phase, it was integrated with CMAS. The performance of colour and COD concentration of AO52 with and without CMAS treatment, is compared and evaluated. From the results, it is obvious that high decolourization from the start of CMAS was contributed from the pre-treatments. The colour removal was due to the fact that ozonation able to cleave the azo bonds that represent colour. Thus, CMAS without pre-treatment are unable to decolourize the dyes sufficiently. 59.6% COD was removed from the first-stage, while merely 9.8% COD fraction removed from the subsequence second-stage CMAS. It is suggested that the rapid COD removal without ozonation are due to activated sludge adsorption processes. The decreased of mixed liquor suspended solids (MLSS) affected the CMAS performances, as the biomass decreased due to lack of nutrient for activated sludge microorganisms to multiply. Results from pre-ozonation alone contributed more than 50% of total COD removal, which indicated that at higher ozone dosage, tend to mineralize azo dye. Thus, ozonation not oxidized the dye though complete mineralization that produce carbon dioxide and water. However, it is a potential process for enhancing colour removal and biodegradability of dye-containing wastewater, once the appropriate ozonation time is determined. Therefore, the role of ozonation seems to break down the dye molecules and created ozonation by-product that is easily biodegraded in the subsequent biological treatment.

  14. Fresnel lens to concentrate solar energy for the photocatalytic decoloration and mineralization of orange II in aqueous solution.

    Science.gov (United States)

    Monteagudo, J M; Durán, A

    2006-11-01

    The decoloration and mineralization of the azo dye orange II under conditions of artificial ultraviolet light and solar energy concentrated by a Fresnel lens in the presence of hydrogen peroxide and TiO(2)-P25 was studied. A comparative study to demonstrate the viability of this solar installation was done to establish if the concentration reached in the focus of the Fresnel lens was enough to improve the photocatalytic degradation reaction. The degradation efficiency was higher when the photolysis was carried out under concentrated solar energy irradiation as compared to UV light source in the presence of an electron acceptor such us H(2)O(2) and the catalyst TiO(2). The effect of hydrogen peroxide, pH and catalyst concentration was also determined. The increase of H(2)O(2) concentration until a critical value (14.7 mM) increased both the solar and artificial UV oxidation reaction rate by generating hydroxyl radicals and inhibiting the (e(-)/h(+)) pair recombination, but the excess of hydrogen peroxide decreases the oxidation rate acting as a radical or hole scavenger and reacting with TiO(2) to form peroxo-compounds, contributing to the inhibition of the reaction. The use of the response surface methodology allowed to fit the optimal values of the parameters pH and catalyst concentration leading to the total solar degradation of orange II. The optimal pH range was 4.5-5.5 close to the zero point charge of TiO(2) depending on surface charge of catalyst and dye ionization state. Dosage of catalyst higher than 1.1 gl(-1) decreases the degradation efficiency due to a decrease of light penetration.

  15. The mechanism for degrading Orange II based on adsorption and reduction by ion-based nanoparticles synthesized by grape leaf extract

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Fang; Yang, Die [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of Environments, University of South Australia, Mawson Lakes, SA 5095 (Australia); Chen, Zuliang, E-mail: zuliang.chen@unisa.edu.au [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of Environments, University of South Australia, Mawson Lakes, SA 5095 (Australia); Megharaj, Mallavarapu; Naidu, Ravendra [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of Environments, University of South Australia, Mawson Lakes, SA 5095 (Australia)

    2015-10-15

    Biomolecules taken from plant extracts have often been used in the single-step synthesis of iron-based nanoparticles (Fe NPs) due to their low cost, environmental safety and sustainable properties. However, the composition of Fe NPs and the degradation mechanism of organic contaminants by them are limited because these are linked to the reactivity of Fe NPs. In this study, Fe NPs synthesized by grape leaf extract served to remove Orange II. Batch experiments showed that more than 92% of Orange II was removed by Fe NPs at high temperature based on adsorption and reduction and confirmed by kinetic studies. To understand the role of Fe NPs in the removal process of azo dye, surface analysis via X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) were employed, showing that the Fe NPs were composed of biomolecules, hydrous iron oxides and Fe{sup 0}, thus providing evidence for the adsorption of Orange II onto hydrous iron oxides and its reduction by Fe{sup 0}. Degraded products such as 2-naphthol were identified using LC–MS analysis. A degradation mechanism based on asymmetrical azo bond cleavage for the removal of Orange II was proposed.

  16. Adsorption of methyl orange and salicylic acid on a nano-transition metal composite: Kinetics, thermodynamic and electrochemical studies.

    Science.gov (United States)

    Arshadi, M; Mousavinia, F; Amiri, M J; Faraji, A R

    2016-12-01

    In this work synthesis of Mn-nanoparticles (MnNPs) supported on the Schiff base modified nano-sized SiO2Al2O3 mixed-oxides (Si/Al) and its implementation as an adsorbent for the removal of organic pollutions such as methyl orange (MO) and salicylic acid (SA) was investigated. Si/Al were functionalized by grafting Schiff base ligand and in the next step, MnNPs were prepared over the modified nano sol-gel Si/Al. Structures and adsorption characteristics of the obtained organometallic-modified SiO2/Al2O3 mixed oxide were studied by several methods such as elemental analysis, diffuse reflectance UV-vis spectroscopy, FT-IR spectroscopy, nitrogen adsorption/desorption, scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX), inductively coupled plasma (ICP-AES), Electron Paramagnetic Resonance (EPR), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). EPR data of the immobilized manganese ions resulted that the transition state of active sites in the nano-adsorbent are in the form of Mn(II) ions at the surface. The adsorption properties of heterogeneous Mn(II) ions showed that this nano-adsorbent has very good potential to remove MO and SA ions from aqueous solution. The removal efficiency of the SAPAS@MnNPs towards MO reached out to 89.3 and 29.1% and for SA approached to 54.6 and 18.9% at 150 and 500mg/dm(3) initial organic pollution concentrations, respectively. To investigate the adsorption kinetic of Mn(II) ions onto the nano-sized support, pseudo first and pseudo second order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherm models have also been applied to the equilibrium adsorption data. The contact time to obtain equilibrium for maximum adsorption capacity was 45min. The adsorption process was spontaneous and endothermic in nature and it was well explained with pseudo-second-order kinetic model. No remarkable loss of removal capacity even after 8th times regeneration

  17. Influence of sub-lethal stresses on the survival of lactic acid bacteria after spray-drying in orange juice.

    Science.gov (United States)

    Barbosa, J; Borges, S; Teixeira, P

    2015-12-01

    The demand for new functional non-dairy based products makes the production of a probiotic orange juice powder an encouraging challenge. However, during drying process and storage, loss of viability of the dried probiotic cultures can occur, since the cells are exposed to various stresses. The influence of sub-lethal conditions of temperature, acidic pH and hydrogen peroxide on the viability of Pediococcus acidilactici HA-6111-2 and Lactobacillus plantarum 299v during spray drying in orange juice and subsequent storage under different conditions was investigated. At the end of storage, the survival of both microorganisms through simulated gastro-intestinal tract (GIT) conditions was also determined. The viability of cells previously exposed to each stress was not affected by the drying process. However, during 180 days of storage at room temperature, unlike P. acidilactici HA-6111-2, survival of L. plantarum 299v was enhanced by prior exposure to sub-lethal conditions. Previous exposure to sub-lethal stresses of each microorganism did not improve their viability after passage through simulated GIT. Nevertheless, as cellular inactivation during 180 days of storage was low, both microorganisms were present in numbers of ca. 10(7) cfu/mL at the end of GIT. This is an indication that both bacteria are good candidates for use in the development of an orange juice powder with functional characteristics.

  18. Removal of basic (Methylene Blue) and acid (Egacid Orange) dyes from waters by sorption on chemically treated wood shavings.

    Science.gov (United States)

    Janos, Pavel; Coskun, Sezen; Pilarová, Vera; Rejnek, Jaroslav

    2009-02-01

    Spruce wood shavings from Picea abies were used for an adsorptive removal of both basic as well as acid dyes from waters. The sorption properties of the sorbents were modified with HCl, Na(2)CO(3) and Na(2)HPO(4). The treatment of the wood sorbents with alkaline carbonate solution as well as with phosphate solution increased the sorption ability for the basic dye (Methylene Blue), whereas the treatment with mineral acid decreased the sorption ability for Methylene Blue to some extent. The opposite is true for the sorption of the acid dye--Egacid Orange. The maximum sorption capacities estimated from the Langmuir-Freundlich isotherms ranged from 0.060 to 0.165 mmol g(-1) for Methylene Blue, and from 0.045 to 0.513 mmol g(-1) for Egacid Orange. The basic dye sorption decreased at low pH values in accordance with a presupposed ion-exchange mechanism of the sorption. The sorption of acid dye, on the other hand, decreased with increasing pH. The presence of inorganic salts as well as surfactants exhibited only minor effects on the dye sorption.

  19. Survival of acid adapted and non-acid adapted Salmonella Typhimurium in pasteurized orange juice and yogurt under different storage temperatures.

    Science.gov (United States)

    Álvarez-Ordóñez, Avelino; Valdés, Lorena; Bernardo, Ana; Prieto, Miguel; López, Mercedes

    2013-10-01

    The survival capacity of Salmonella enterica serovar Typhimurium acid adapted and non-acid adapted cells was monitored in pasteurized yogurt (pH 4.1) and orange juice (pH 3.6) during storage at different temperatures (4, 10, 25 and 37 ). Acid adapted and non-acid adapted cells were obtained by means of their growth for 36 h in Brain Heart Infusion broth acidified at pH 4.8 with citric acid and buffered (pH 7.0) Brain Heart Infusion broth, respectively. S. typhimurium showed a great ability to survive in both foodstuffs and, especially, in yogurt, where both acid adapted and non-acid adapted populations suffered only a reduction of about 1.3-1.9 log10 cycles after 43 days of storage in the range of temperatures 4-25 . At 37  a higher bacterial inactivation was observed (4.0-4.4 log10 cycles). In orange juice, a different behaviour was observed for acid-adapted and non-acid adapted cells. Whereas non-acid adapted cells survived better than acid adapted cells at 4 and 10 , acid adapted cells showed enhanced survival abilities at higher temperatures (25 and 37 ). Thus, the times required to achieve a 5 log10 cycles reduction for non-acid adapted and acid adapted cells were 10.2 and 6.0 (4 ), 6.3 and 4.2 (10 ), 0.6 and 1.0 (25 ) and 0.10 and 0.15 (37 ) days, respectively. Evidence found in this study demonstrates that refrigeration temperatures protect S. typhimurium from inactivation in acid foods and indicates that S. typhimurium acid tolerance response (ATR) is determined by storage temperature and food composition.

  20. A single amino acid substitution in an ORANGE protein promotes carotenoid overaccumulation in arabidopsis

    Science.gov (United States)

    Carotenoids are crucial for plant growth and human health. The finding of ORANGE (OR) protein as a pivotal regulator of carotenogenesis offers a unique opportunity to comprehensively understand the regulatory mechanisms of carotenoid accumulation and develop crops with enhanced nutritional quality. ...

  1. N, S co-doped carbon dots with orange luminescence synthesized through polymerization and carbonization reaction of amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Ya-Wen [Nanomaterials and Chemistry Key Laboratory, Wenzhou University, Wenzhou, Zhejiang 325027 (China); Ma, De-Kun, E-mail: dkma@wzu.edu.cn [Nanomaterials and Chemistry Key Laboratory, Wenzhou University, Wenzhou, Zhejiang 325027 (China); Wang, Wei; Chen, Jing-Jing; Zhou, Lin; Zheng, Yi-Zhou [Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027 (China); Yu, Kang, E-mail: yukang62@126.com [Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027 (China); Huang, Shao-Ming, E-mail: smhuang@wzu.edu.cn [Nanomaterials and Chemistry Key Laboratory, Wenzhou University, Wenzhou, Zhejiang 325027 (China)

    2015-07-01

    Graphical abstract: N, S co-doped CDs with orange luminescence were synthesized through one-pot polymerization and carbonization reactions under hydrothermal conditions, using two different amino acids as raw materials. - Highlights: • N, S co-doped CDs were synthesized by one-pot carbonization reactions, using two different amino acids as raw materials. • The as-obtained N, S co-doped CDs showed unique orange fluorescence under excitation at room temperature. • The products could be applied in the imaging of peritoneal macrophages of mice without any functionalization. - Abstract: For practical application, it is highly desirable to obtain carbon dots (CDs) through environmentally benign synthetic route, using green raw materials. On the other hand, at present, most of CDs reported in the literature showed blue, green and yellow emission. Therefore it is still necessary to develop new strategy to obtain CDs with longer wavelength emission in order to expand their application range. Toward this end, in this study, N, S co-doped CDs were synthesized through one-pot condensation polymerization and carbonization reactions under hydrothermal conditions, using two different amino acids as raw materials. Taking the reaction of L-serine with L-cystine as an example, the as-obtained products were characterized by various techniques such as transmission electron microscopy, elemental analysis, Fourier-transform infrared spectrum, X-ray photoelectron spectra, and so on. Interestingly, N, S co-doped CDs displayed unique orange emission at room temperature. The possible photoluminescence mechanism of N, S co-doped CDs was proposed. Furthermore, the as-synthesized N, S co-doped CDs were directly applied in the imaging of peritoneal macrophages of mice.

  2. Photocatalytic decolouration of Orange II by ZnO active layers screen-printed on ceramic tiles.

    Science.gov (United States)

    Marto, J; São Marcos, P; Trindade, T; Labrincha, J A

    2009-04-15

    In this work ZnO layers have been deposited by screen-printing in common ceramic tiles. These layers were characterized and tested for the photocatalytic degradation of the organic dye Orange II in aqueous solutions, using a batch photoreactor either under visible light provided by a Philips ML-160 W lamp or under direct exposure to sunlight. For sake of comparison, ZnO suspensions have also been evaluated for similar reacting conditions. The influence of experimental parameters such as (i) firing temperature of the printed layer; (ii) layer thickness; and (iii) operation time have been investigated. Screen-printed ZnO layers obtained in optimal processing conditions showed photocatalytic activity comparable to aqueous ZnO suspensions. The maximal attenuation degree is over 70% and decolourisation rate, assuming that reaction kinetics follows a pseudo-first order rate law, is over 0.015 min(-1). Thus these ZnO-layered ceramic tiles can be regarded as an alternative to photocatalytic suspensions of the same material with the advantage of avoiding the removal of the photocatalyst.

  3. Effect of cyclic AMP and acridine orange on the enzymatic reduction of usnic acid in the lichen Usnea aurantiaco-atra (Jacq. Bory

    Directory of Open Access Journals (Sweden)

    C. Vicente

    2014-01-01

    Full Text Available A fluorescence-detection HPLC procedure has been applied to identify and quantify acridine orange in lichen samples. The dye accumulates in thalli of the lichen Usnea aurantiaco-atra and, in part, it is recovered from protamine-precipitated nucleic acids extracted from the samples. A supply of exogenous cyclic AMP reverses the uptake of acridine orange by thallus samples and its binding to nucleic acids. The dye impedes neither the loss of endogenously-produced cyclic AMP by thallus samples nor inhibits the uptake of that exogenously supplied. However, part of the endogenously produced cyclic AMP is secreted to the incubation medium in which phosphodiesterase activity has never been detected. Since the synthesis of D-usnic acid: NAD+(H oxido-reductase is impeded by acridine orange, oxidative catabolism of usnic acid is inhibited in thalli floated on the dye. Cyclic AMP reverses this effect.

  4. Modelling of the simultaneous photodegradation of Acid Red 97, Acid Orange 61 and Acid Brown 425 using factor screening and response surface strategies.

    Science.gov (United States)

    Fernández, Cristina; Larrechi, M Soledad; Callao, M Pilar

    2010-08-15

    In this paper the influence of seven variables that could be relevant in the photodegradation of three textile dyes - Acid Red 97, Acid Orange 61 and Acid Brown 425 - has been studied with the aim of determining the most efficient conditions for this process. The type and concentration of catalyst, the presence and concentration of H(2)O(2), the stirring, the pH and the dye concentration have been studied as variables. In the first stage the more basic variables were analyzed using a screening methodology (saturated fractional factorial design) and it was concluded that the most influential variable was the presence of H(2)O(2). In the second stage, a central composite design was used to establish a response surface for the behavior of the photodegradation. In this stage the concentration of Acid Brown 425 was fixed and the degradation was carried out without catalyst. The most remarkable aspects of the experiment are that brown dye is always the most persistent in the solution and that a catalyst is not needed to degrade the dyes quickly. A second-order equation is needed to model this process. The response surface obtained could be useful for reducing the time and money needed to treat effluent wastewater. Copyright 2010 Elsevier B.V. All rights reserved.

  5. Thermodynamical and structural insights of orange II adsorption by Mg RAlNO 3 layered double hydroxides

    Science.gov (United States)

    Mustapha Bouhent, Mohamed; Derriche, Zoubir; Denoyel, Renaud; Prevot, Vanessa; Forano, Claude

    2011-05-01

    [Mg 1- x Al x(OH) 2][(NO 3) x, nH 2O] Layered Double Hydroxide (LDH) sorbents with variable Mg/Al molar ( R=(1- x)/ x) ratios were investigated for adsorption of azo dye, orange II (OII) at various pH and temperature conditions. Mg 2AlNO 3 displays the highest adsorption capacity with 3.611 mmol of OII per gram of Mg 2AlNO 3 at 40 °C. Adsorption isotherms have been fitted using the Langmuir model and free energy of adsorption (Δ G°), enthalpy (Δ H°) and entropy (Δ S°) were calculated. The experimental values for Δ G° in temperature range between 10 and 40 °C were found to be negative indicating that a spontaneous process occurred. Positive calculated enthalpy values, characteristic of an endothermic process were found. Characterization of solids (PXRD, FTIR, UV-vis, TGA/DTA, adsorption isotherm BET analysis, SEM and Zetametry) before and after adsorption showed that adsorption proceeds in two steps. First, adsorption occurs at the LDH surface, followed by intercalation via anion exchange.

  6. TiO2/ZnS/CdS Nanocomposite for Hydrogen Evolution and Orange II Dye Degradation

    Directory of Open Access Journals (Sweden)

    Václav Štengl

    2011-01-01

    Full Text Available TiO2/ZnS/CdS composites for photocatalytic hydrogen production from water were prepared by homogeneous hydrolysis of aqueous solutions mixture of TiOSO4, ZnSO4, and CdSO4 with thioacetamide. Hydrogen evolution was observed in the presence of palladium and platinum nanoparticles deposited on TiO2/ZnS/CdS composites. The morphology was obtained by scanning electron microscopy, the nitrogen adsorption-desorption was used for determination of surface area (BET and porosity. The method of UV-VIS diffuse reflectance spectroscopy was employed to estimate band-gap energies of prepared TiO2/ZnS/CdS nano-composites. The photocatalytic activity of the prepared samples were assessed by photocatalytic decomposition of Orange II dye in an aqueous slurry under UV irradiation at 365 nm wavelength and visible light up to 400 nm wavelength. Doped titanium dioxide by the CdS increased band-gap energy and doping with ZnS increased photocatalytic activity. The best photocatalytic activity for H2 evolution shows sample named TiZnCd7 on surface deposited with palladium, which contains 20.21% TiO2, 78.5% ZnS, and 1.29% CdS.

  7. Anatase/rutile TiO{sub 2} composites: Influence of the mixing ratio on the photocatalytic degradation of Malachite Green and Orange II in slurry

    Energy Technology Data Exchange (ETDEWEB)

    Bojinova, A.; Kralchevska, R. [Department of General and Inorganic Chemistry, Faculty of Chemistry, University of Sofia, Sofia 1164 (Bulgaria); Poulios, I. [Laboratory of Physical Chemistry, Department of Chemistry, Aristotle University, 54124 Thessaloniki (Greece); Dushkin, C. [Department of General and Inorganic Chemistry, Faculty of Chemistry, University of Sofia, Sofia 1164 (Bulgaria)], E-mail: nhtd@wmail.chem.uni-sofia.bg

    2007-12-15

    The present study is directed to clarify the influence of the ratio of anatase to rutile phase, containing in the TiO{sub 2} samples, on their activity as photocatalysts in slurry. A series of samples corresponding to different percentages of anatase is prepared from commercial anatase and rutile TiO{sub 2} brands (KRONOS). The crystalline phase composition of the samples is characterized by X-ray diffraction. The photocatalytic action of the mixtures is tested in photodegradation of the commercial organic dyes Malachite Green Hydrochloride and Orange II in aqueous solutions under UV irradiation. Comparative tests with Degussa P-25 are performed. The apparent rate constants of the process are determined from the kinetic curves using appropriate models. They generally increase with the anatase ratio, being always larger for Malachite Green than for Orange II.

  8. Heterogeneous photo-Fenton decolorization of Orange II over Al-pillared Fe-smectite: Response surface approach, degradation pathway, and toxicity evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Huiyuan; Li, Yanli [Department of Environmental Engineering, Wuhan University, Wuhan 430079 (China); Xiang, Luojing [Department of Environmental Engineering, Wuhan University, Wuhan 430079 (China); Université de Poitiers, UMR CNRS 7285, IC2MP, ENSIP, B1, 1 rue Marcel Doré, TSA 41105, Poitiers 86073 Cedex 9 (France); Huang, Qianqian; Qiu, Juanjuan [Department of Environmental Engineering, Wuhan University, Wuhan 430079 (China); Zhang, Hui, E-mail: eeng@whu.edu.cn [Department of Environmental Engineering, Wuhan University, Wuhan 430079 (China); Sivaiah, Matte Venkata; Baron, Fabien; Barrault, Joel; Petit, Sabine [Université de Poitiers, UMR CNRS 7285, IC2MP, ENSIP, B1, 1 rue Marcel Doré, TSA 41105, Poitiers 86073 Cedex 9 (France); Valange, Sabine, E-mail: sabine.valange@univ-poitiers.fr [Université de Poitiers, UMR CNRS 7285, IC2MP, ENSIP, B1, 1 rue Marcel Doré, TSA 41105, Poitiers 86073 Cedex 9 (France)

    2015-04-28

    Highlights: • Al-pillared Fe-smectite was synthesized and used as the photo-Fenton catalyst. • Response surface methodology was used to study the effects of reaction parameters. • The main intermediate products were identified by GC–MS technique. • A possible degradation pathway of Orange II was proposed. • All the generated products of Orange II were less toxic than the original dye. - Abstract: A ferric smectite clay material was synthesized and further intercalated with Al{sub 2}O{sub 3} pillars for the first time with the aim of evaluating its ability to be used as heterogeneous catalyst for the photo-Fenton decolorization of azo dye Orange II. UV irradiation was found to enhance the activity of the catalyst in the heterogeneous photo-Fenton process. Catalyst loading of 0.5 g/L and hydrogen peroxide concentration of 13.5 mM yielded a remarkable color removal, accompanied by excellent catalyst stability. The decolorization of Orange II followed the pseudo-first-order kinetics for initial dye concentrations from 20 to 160 mg/L. The central composite design (CCD) based on the response surface methodology (RSM) was applied to evaluate the effects of several operating parameters, namely initial pH, catalyst loading and hydrogen peroxide concentration, on the decolorization efficiency. The RSM model was derived and the response surface plots were developed based on the results. Moreover, the main intermediate products were separated and identified using gas chromatography–mass spectrometry (GC–MS) and a possible degradation pathway was proposed accordingly. The acute toxicity experiments illustrated that the Daphniamagna immobilization rate continuously decreased during 150 min reaction, indicating that the effluent was suitable for sequential biological treatment.

  9. Genetic variation and balancing selection at MHC class II exon 2 in cultured stocks and wild populations of orange-spotted grouper (Epinephelus coioides).

    Science.gov (United States)

    Meng, Z N; Yang, S; Fan, B; Wang, L; Lin, H R

    2012-11-12

    Major histocompatibility complex (MHC) molecules play vital roles in triggering adaptive immune responses and are considered the most variable molecules in vertebrates. Recently, many studies have focused on the polymorphism and evolution mode of MHC in both model and non-model organisms. Here, we analyzed the MHC class II exon 2-encoding β chain in comparison with the mitochondrial Cytb gene and our previously published microsatellite data set in three cultured stocks and four wild populations of the orange-spotted grouper (Epinephelus coioides) in order to investigate its genetic variation and mechanism of evolution. We detected one to four alleles in one individual, suggesting that at least two loci exist in the orange-spotted grouper, as well as a particularly high level of allelic diversity at the MHC loci. Furthermore, the cultured stocks exhibited reduced allelic diversity compared to the wild counterparts. We found evidence of balancing selection at MHC class II exon 2, and codon sites under positive selection were largely correspondent to the protein-binding region. In addition, MHC class II exon 2 revealed significant differences between population differentiation patterns from the neutral mitochondrial Cytb and microsatellites, which may indicate local adaptation at MHC loci in orange-spotted grouper originating from the South China Sea and Southeast Asia.

  10. Ultrasound enhanced heterogeneous activation of peroxymonosulfate by a bimetallic Fe-Co/SBA-15 catalyst for the degradation of Orange II in water.

    Science.gov (United States)

    Cai, Chun; Zhang, Hui; Zhong, Xing; Hou, Liwei

    2015-01-01

    Mesoporous silica SBA-15 supported iron and cobalt (Fe-Co/SBA-15) was prepared and used as catalyst in the ultrasound (US) enhanced heterogeneous activation of peroxymonosulfate (PMS, HSO5(-)) process. The effects of some important reaction parameters on the removal of Orange II by US/Fe-Co/SBA-15/PMS process were investigated. The results indicated that the removal rate of Orange II was not significantly affected by the initial pH, and it increased with the higher PMS concentration, reaction temperature, Fe-Co/SBA-15 dosage and ultrasonic power. Furthermore, sulfate radicals (SO4(-)) were assumed to be the dominating reactive species for the Orange II decolorization. Moreover, the Fe-Co/SBA-15 catalyst showed high activity during the repeated experiments. The intermediate products were identified by GC-MS, thereby a plausible degradation pathway is proposed. In addition, the chemical oxygen demand (COD) removal efficiencies at 2 and 24h were 56.8% and 80.1%, respectively and the corresponding total organic carbon (TOC) removal efficiencies were 33.8 and 53.3%. Finally, toxicity tests with activated sludge showed that the toxicity of the solution increased during the first stage and then decreased significantly with the progress of the oxidation.

  11. Determination of creatinine, uric and ascorbic acid in bovine milk and orange juice by hydrophilic interaction HPLC.

    Science.gov (United States)

    Zuo, Ruiting; Zhou, Si; Zuo, Yuegang; Deng, Yiwei

    2015-09-01

    Creatinine (Cr), uric (UA) and ascorbic acid (AA) are common constituents in human fluids. Their abnormal concentrations in human fluids are associated with various diseases. Thus, apart from the endogenous formation in human body, it is also important to examine their sources from food products. In this study, a rapid and accurate HILIC method was developed for simultaneous determination of Cr, UA and AA in bovine milk and orange juice. Milk samples were pretreated by protein precipitation, centrifugation and filtration, followed by HPLC separation and quantification using a Waters Spherisorb S5NH2 column. The developed method has been successfully applied to determine the concentration of UA, AA and Cr in milk and fruit juice samples. The milk samples tested were found to contain UA and creatinine in the concentration range of 24.1-86.0 and 5.07-11.2 μg mL(-1), respectively. The orange juices contain AA over 212 μg mL(-1).

  12. STUDY ON THE SUGAR-ACID RATIO AND RELEVANT METABOLIZING ENZYME ACTIVITIES IN NAVEL ORANGE FRUITS FROM DIFFERENT ECO-REGIONS

    Directory of Open Access Journals (Sweden)

    GONG RONGGAO

    2015-12-01

    Full Text Available ABSTRACT The flavor quality of citrus fruits is largely determined by the sugar-acid ratio, but it remains uncertain how sugar- and/or acid-metabolizing enzymes regulate the sugar-acid ratio of navel oranges and further affect the fruit quality. In the present study, Robertson navel oranges (Citrus sinesis Osb. were collected from six representative habitats in three eco-regions of Sichuan, China. The changes in the sugar-acid ratio and the activities of sucrose phosphate synthase (SPS, sucrose synthase (SS, cytosolic cio-aconitase (ACO, and isocitrate dehydrogenase (IDH were examined in navel oranges during fruit development. The results indicated that the sugar-acid ratio of fruits in different eco-regions changed significantly from 150 days after full bloom. The SPS and cytosolic ACO fruit activities had minor changes among different ecoregions throughout the experimental periods, whereas the activities of SS and IDH changed significantly in fruits among three eco-regions. Furthermore, the sugar-acid ratio and the activities of SS in the synthetic direction and IDH were the highest in south subtropics and the lowest in north mid-subtropics, probably due to the effects of climate conditions and/or other relevant eco-factors. It demonstrated that SS in the synthetic direction and IDH were of greater importance in regulating the sugar-acid ratio of navel oranges in different eco-regions, which provided new insights into the factors that determine the flavor quality of navel oranges and valuable data for guiding relevant agricultural practices.

  13. Photocatalytic degradation of acid orange 7 in aqueous solution with La3+-doped TiO2 photocatalysts

    Institute of Scientific and Technical Information of China (English)

    XIA Changbin; ZHOU Yi; LI Xun; ZENG Jing; XU Ruiyin

    2005-01-01

    Nanocrystalline La3+-doped TiO2 of 20-30 nm in size was prepared by a sol-gel technique. The photocatalytic activities of the samples were evaluated by the degradation of harmful acid orange 7(AO7) azo-dye in aqueous solution. The effects of La3+ ion implantation on the photocatalytic activity of TiO2 were also discussed. The results show that the La3+content plays an essential role in affecting the photocatalytic activity of the La3+-doped TiO2 and the optimum content of La3+-doped is 1.0 wt.%. The photocatalytic activity of the samples with La3+-doped TiO2 is higher than that of pure TiO2 in the treatment of AO7 wastewater. The photodegradation effect of AO7 effluent is the best by means of La3+-doped TiO2 with 1.0% La3+.

  14. A novel photochemical system of ferrous sulfite complex: kinetics and mechanisms of rapid decolorization of Acid Orange 7 in aqueous solutions.

    Science.gov (United States)

    Zhou, Danna; Chen, Long; Zhang, Changbo; Yu, Yingtan; Zhang, Li; Wu, Feng

    2014-06-15

    We previously reported the decolorization of the azo dye Acid Orange 7 (AO7) by sulfate radical (SO4(-)) in the presence of iron(II) sulfite complex and oxygen under UV-vis irradiation (photo-iron(II) sulfite system). This system, however, achieves very limited mineralization of AO7 (in terms of total organic carbon (TOC) removal), which is not in accordance with literature reports on the oxidation of organic contaminants by SO4(-). In the present work, kinetics and products under irradiation of xenon lamp (350 W) were analyzed to reveal the reaction pathway of decolorization of AO7. Steady-state approximation (SSA) of SO4(-) radicals and apparent kinetics of AO7 were examined. The reaction between AO7 and SO4(-) was found to proceed in two steps, namely, electron transfer and SO4(-) addition. The second-order rate constant for the reaction between AO7 and SO4(-) was found to be 8.07 ± 1.07 × 10(9) M(-1) s(-1) by SSA and 6.80 ± 0.68 × 10(9) M(-1) s(-1) by competition kinetics method. The apparent kinetics of the decolorization of AO7 under irradiation closely fits the mechanism of radical chain reactions of various reactive sulfur species. By liquid chromatography coupled with mass spectrometry, we identified the sulfate adduct AO7-SO4 and confirmed the two-step reaction between AO7 and SO4(-). This stable sulfate adduct provides a good explanation of the poor TOC removal during decolorization of AO7 by the photo-iron(II) sulfite system.

  15. Research Advances in the Detection Methods of Non-edible Pigment of Acid Orange Ⅱ%非食用色素酸性橙Ⅱ的检测方法研究进展

    Institute of Scientific and Technical Information of China (English)

    廖上铁

    2012-01-01

    The detection methods of acid orange II in food were reviewed, including the HPLC-hased methods, such as HPLC, Re-HPLC, HPLC-MS and UPLC, and other detection methods, such as ELISA, TLCs, fluorescence spectroscopy and polarograph. The research aimed to provide references for improving the detection methods of acid orange II.%对食品中酸性橙Ⅱ的检测方法进行了综述,其中包括基于高效液相色谱( HPLC)的检测方法,如HPLC法、反相高效液相色谱(Re-HPLC)法、高效液相色谱-质谱(HPLC-MS)法、超高效液相色谱(UPLC)法,以及其他检测方法,如酶联免疫(ELISA)法、薄层色谱扫描法、荧光光谱检测法和极谱法,以期为酸性橙Ⅱ检测方法的改进提供依据.

  16. The cyanobacterial Fluorescence Recovery Protein has two distinct activities: Orange Carotenoid Protein amino acids involved in FRP interaction.

    Science.gov (United States)

    Thurotte, Adrien; Bourcier de Carbon, Céline; Wilson, Adjélé; Talbot, Léa; Cot, Sandrine; López-Igual, Rocio; Kirilovsky, Diana

    2017-04-01

    To deal with fluctuating light condition, cyanobacteria have developed a photoprotective mechanism which, under high light conditions, decreases the energy arriving at the photochemical centers. It relies on a photoswitch, the Orange Carotenoid Protein (OCP). Once photoactivated, OCP binds to the light harvesting antenna, the phycobilisome (PBS), and triggers the thermal dissipation of the excess energy absorbed. Deactivation of the photoprotective mechanism requires the intervention of a third partner, the Fluorescence Recovery Protein (FRP). FRP by interacting with the photoactivated OCP accelerates its conversion to the non-active form and its detachment from the phycobilisome. We have studied the interaction of FRP with free and phycobilisome-bound OCP. Several OCP variants were constructed and characterized. In this article we show that OCP amino acid F299 is essential and D220 important for OCP deactivation mediated by FRP. Mutations of these amino acids did not affect FRP activity as helper to detach OCP from phycobilisomes. In addition, while mutated R60L FRP is inactive on OCP deactivation, its activity on the detachment of the OCP from the phycobilisomes is not affected. Thus, our results demonstrate that FRP has two distinct activities: it accelerates OCP detachment from phycobilisomes and then it helps deactivation of the OCP. They also suggest that different OCP and FRP amino acids could be involved in these two activities.

  17. 钛酸纳米管光催化降解甲基橙的研究%Study on Photocatalytic Degradation of Methyl Orange by Titanic Acid Nanotubes

    Institute of Scientific and Technical Information of China (English)

    孔德国; 张红美; 杨瑛; 罗华平

    2013-01-01

    在紫外灯照射下,以钛酸纳米管为催化剂对甲基橙溶液进行光催化降解.结果表明,甲基橙初始浓度、催化剂用量及光照时间均对甲基橙降解率有一定程度的影响,而pH则几乎无影响.在35 mL初始浓度为10 mg/L甲基橙溶液、30 mg催化剂、pH中性、紫外光照60 min条件下,甲基橙降解率达到99.6%.%Using titanic acid nanotubes as catalyst,methyl orange was degraded under UV radiation.The results indicated that the initial concentration of methyl orange,amount of catalyst and illuminative time had some effects on the degradation rate,while pH of the solution hadn't influence on the degradation of methyl orange.The optimal conditions was 30 mg catalyst that added into 35 mL,pH 7.0,10 mg/L methyl orange solution,UV radiation for 60 minutes,the degradation rate of methyl orange reached 99.6%.

  18. Effect of Different Conditions of Growth and Storage on the Cell Counts of Two Lactic Acid Bacteria after Spray Drying in Orange Juice

    Directory of Open Access Journals (Sweden)

    Joana Barbosa

    2016-03-01

    Full Text Available Consumers increasingly require innovative food products with health benefits. Thus, a dried orange juice incorporating probiotics could be a novel challenge. In this context, we investigated whether different sugars added to the culture media used for growth of two lactic acid bacteria contributed to their protection during spray drying in orange juice and subsequent storage under different conditions of temperature, light exposure and water activity. Cell viability during passage through simulated gastro-intestinal conditions was also investigated. Cells grown in culture medium containing fructose resulted in the worst survival rates during storage. High survival was observed for cells grown in the presence of lactose, followed by glucose. The survival of dried bacteria was enhanced at 4 °C, water activity of 0.03 and absence of daylight. For cells grown in standard culture medium and after 12 months of storage at 4 °C in orange juice powder (about 109 cfu/mL, there was a reduction of approximately 2 log-units for both lactic acid bacteria after gastro-intestinal tract passage simulation. Using the conditions of growth and storage investigated, it is possible to improve the survival rate of lactic acid bacteria and produce an orange juice powder with probiotic characteristics with shelf life of at least 12 months.

  19. Orange Book

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Approved Drug Products with Therapeutic Equivalence (Orange Book or OB) is a list of drugs approved under Section 505 of the Federal Food, Drug and Cosmetic Act...

  20. Effect of initial solution pH on the degradation of Orange II using clay-based Fe nanocomposites as heterogeneous photo-Fenton catalyst.

    Science.gov (United States)

    Feng, Jiyun; Hu, Xijun; Yue, Po Lock

    2006-02-01

    Effect of initial solution pH on the discoloration and mineralization of 0.2 mM Orange II by using two clay-based Fe nanocomposites (Fe-B (Fe supported on bentonite clay) and Fe-Lap-RD (Fe supported on laponite clay)) as catalysts was studied in detail. It was found that the initial solution pH not only influences the photo-catalytic activity of Fe-B and Fe-Lap-RD but also the Fe leaching from the two catalysts. Both catalysts show the best photo-catalytic activity at an initial solution pH of 3.0, and the activity of the catalysts decreases as the initial solution pH increases. At optimal conditions, 100% discoloration and mineralization of 0.2 mM Orange II are achieved in 60 and 120 min reaction in the presence of 10 mM H2O2, 1.0 g/L Fe-B, and 1 x 8 W UVC at initial solution pH of 3.0. 100% discoloration and 90% mineralization of 0.2 mM Orange II are achieved when Fe-Lap-RD is used as catalyst under the same conditions. Both catalysts also display a reasonable good photo-catalytic activity and negligible Fe leaching at an initial solution pH of 6.6 that is very close to neutral pH. This characteristic makes it possible for the Fe-B and Fe-Lap-RD to have a long-term stability. It also becomes feasible for the photo-Fenton process to treat the original wastewater without the need to pre-adjust the solution pH.

  1. High performance degradation of azo dye Acid Orange 7 and sulfanilic acid in a laboratory scale reactor after seeding with cultured bacterial strains.

    Science.gov (United States)

    Coughlin, Michael F; Kinkle, Brian K; Bishop, Paul L

    2003-06-01

    Bacterial strains 1CX and SAD4i--previously isolated from the mixed liquor of a municipal sewage treatment plant--are capable of degrading the azo dye Acid Orange 7 (AO7) and sulfanilic acid, respectively. A rotating drum bioreactor (RDBR), operating under continuous flow and nutrient conditions designed to simulate the effluent from a dye manufacturing plant, was seeded with strains 1CX and SAD4i, forming a biofilm capable of degrading AO7 and sulfanilic acid. In addition, an RDBR containing a pre-existing biofilm capable of degrading AO7, but not sulfanilic acid, was seeded with strain SAD4i alone. Strain SAD4i was incorporated into the existing biofilm and degraded the sulfanilic acid resulting from the degradation of AO7 by indigenous members of the biofilm. The ability to seed a bioreactor with bacterial strains capable of degrading azo dyes, and resulting by-products, in a mixed microbial community suggests that this process could have commercial applications.

  2. Ni(II) complexes of dithiophosphonic acids

    Indian Academy of Sciences (India)

    Afshin Saadat; Alireza Banaee; Patrick McArdle; Karim Zare; Khodayar Gholivand; Ali Asghar Ebrahimi Valmoozi

    2014-07-01

    The reaction of 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (Lawesson reagent) with isobutanol, cyclohexylamine and phenylethylamine produced (4-methoxy-phenyl)-phosphonodithioic acid o-isobutyl ester HS2P(p-C6H4OMe) (OCH2CH(CH3)2) (I), [S2P(C6H11NH)(p-C6H4OMe) H3N+C6H11] (II) and [S2P(phCH2CH2NH) (p-C6H4OMe)H3N+CH2CH2ph] (III), respectively. The reaction of alcohol with Lawesson reagent produced neutral product (I) while that with amines led to an ion pair (II, III). Furthermore, reaction of I, II and III with NiCl2.6H2O in methanol produced novel complexes: IV, V and VI. The compounds were characterized by 1H, 13C and 31P NMR, IR spectroscopy and elemental analysis. The single crystal X-ray structures of IV and V showed that the nickel complexes are square planar. Compound V formed a three-dimensional supramolecular structure via intermolecular P-O…H-N hydrogen bonds. The Xray crystallography of V showed that those three hydrogens of +NH3 cation produced three hydrogen bonds with different distances. The new compounds were additionally tested in view of their anti-bacterial properties. The ligands containing amine substituents exhibited more activity toward tested bacteria than their alcohol substituents, while the Ni(II) complexes including alcohol substituents exhibited high potential.

  3. Computational photochemistry of the azobenzene scaffold of Sudan I and Orange II dyes: excited-state proton transfer and deactivation via conical intersections.

    Science.gov (United States)

    Guan, Pei-Jie; Cui, Ganglong; Fang, Qiu

    2015-03-16

    We employed the complete active space self-consistent field (CASSCF) and its multistate second-order perturbation (MS-CASPT2) methods to explore the photochemical mechanism of 2-hydroxyazobenzene, the molecular scaffold of Sudan I and Orange II dyes. It was found that the excited-state intramolecular proton transfer (ESIPT) along the bright diabatic (1) ππ* state is barrierless and ultrafast. Along this diabatic (1) ππ* relaxation path, the system can jump to the dark (1) nπ* state via the (1) ππ*/(1) nπ* crossing point. However, ESIPT in this dark state is largely inhibited owing to a sizeable barrier. We also found two deactivation channels that decay (1) ππ* keto and (1) nπ* enol species to the ground state via two energetically accessible S1 /S0 conical intersections. Finally, we encountered an interesting phenomenon in the excited-state hydrogen-bonding strength: it is reinforced in the (1) ππ* state, whereas it is reduced in the (1) nπ* state. The present work sets the stage for understanding the photophysics and photochemistry of Sudan I-IV, Orange II, Ponceau 2R, Ponceau 4R, and azo violet.

  4. Electrochemical enhanced heterogeneous activation of peroxydisulfate by Fe-Co/SBA-15 catalyst for the degradation of Orange II in water.

    Science.gov (United States)

    Cai, Chun; Zhang, Hui; Zhong, Xin; Hou, Liwei

    2014-12-01

    Mesoporous silica SBA-15 supported iron and cobalt catalysts (Fe-Co/SBA-15) were prepared and used in the electrochemical (EC) enhanced heterogeneous activation of peroxydisulfate (PDS, S2O8(2-)) process for the removal of Orange II. The effects of some important reaction parameters such as initial pH, current density, PDS concentration and dosage of Fe-Co/SBA-15 catalysts were investigated. The results showed that the decolorization efficiency was not significantly affected by the initial pH value, and it did increase with the higher PDS concentration, current density and Fe-Co/SBA-15 dosage. Both the sulfate radical (SO4(·-)) and the hydroxyl radical (OH) are considered as the primary reactive oxidants for the Orange II decolorization. The Fe-Co/SBA-15 catalyst maintained its high activity during repeated batch experiments. The intermediate products were identified by GC-MS analysis and a plausible degradation pathway is proposed accordingly. The removal efficiencies of chemical oxygen demand (COD) and total organic carbon (TOC) were 52.1% and 31.9%, respectively after 60 min of reaction time but reached 82.9% and 51.5%, respectively when the reaction time was extended to 24 h. Toxicity tests with activated sludge indicated that the toxicity of the solution increased during the first 30 min and then decreased as the oxidation proceeded.

  5. Heterogeneous photo-Fenton decolorization of Orange II over Al-pillared Fe-smectite: response surface approach, degradation pathway, and toxicity evaluation.

    Science.gov (United States)

    Li, Huiyuan; Li, Yanli; Xiang, Luojing; Huang, Qianqian; Qiu, Juanjuan; Zhang, Hui; Sivaiah, Matte Venkata; Baron, Fabien; Barrault, Joel; Petit, Sabine; Valange, Sabine

    2015-04-28

    A ferric smectite clay material was synthesized and further intercalated with Al2O3 pillars for the first time with the aim of evaluating its ability to be used as heterogeneous catalyst for the photo-Fenton decolorization of azo dye Orange II. UV irradiation was found to enhance the activity of the catalyst in the heterogeneous photo-Fenton process. Catalyst loading of 0.5g/L and hydrogen peroxide concentration of 13.5mM yielded a remarkable color removal, accompanied by excellent catalyst stability. The decolorization of Orange II followed the pseudo-first-order kinetics for initial dye concentrations from 20 to 160mg/L. The central composite design (CCD) based on the response surface methodology (RSM) was applied to evaluate the effects of several operating parameters, namely initial pH, catalyst loading and hydrogen peroxide concentration, on the decolorization efficiency. The RSM model was derived and the response surface plots were developed based on the results. Moreover, the main intermediate products were separated and identified using gas chromatography-mass spectrometry (GC-MS) and a possible degradation pathway was proposed accordingly. The acute toxicity experiments illustrated that the Daphniamagna immobilization rate continuously decreased during 150min reaction, indicating that the effluent was suitable for sequential biological treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Kinetic analysis of acid orange 7 degradation by pulsed discharge plasma combined with activated carbon and the synergistic mechanism exploration.

    Science.gov (United States)

    Guo, He; Wang, Huijuan; Wu, Qiangshun; Zhou, Guangshun; Yi, Chengwu

    2016-09-01

    The synergistic technique of pulsed discharge plasma (PDP) and activated carbon (AC) was built to investigate the kinetics of acid orange 7 (AO7) degradation under different conditions of AC addition, electrode gap, initial pH value of solution, gas variety and gas flow rate. Emission spectra of OH and O, UV-vis absorption spectra of the AO7 solution and TOC removal were measured to illustrate the synergistic mechanism of the PDP and the AC. The obtained results indicated that the kinetic constant of AO7 degradation increased from 0.00947 min(-1) to 0.01419 min(-1) when 4 g AC was added into the PDP system; AO7 degradation was higher in the case of alkaline solution when oxygen was used as the flow gas in the PDP/AC system, 2 L/min oxygen flow was more favorable for the degradation. Results of the relative emission intensities of OH and O indicated the catalytic effect of the AC on the active species formation as well as the important role of the two radicals for the AO7 degradation. There was no new peaks appeared by the UV-vis analysis of the AO7 solution after 60 min treatment. The highest TOC removal in the PDP/AC system was 30.3%, which was achieved under the condition of 4 L/min air flow rate and 3 initial pH value.

  7. Enhancement of azo dye Acid Orange 7 removal in newly developed horizontal subsurface-flow constructed wetland.

    Science.gov (United States)

    Tee, Heng-Chong; Lim, Poh-Eng; Seng, Chye-Eng; Mohd Nawi, Mohd Asri; Adnan, Rohana

    2015-01-01

    Horizontal subsurface-flow (HSF) constructed wetland incorporating baffles was developed to facilitate upflow and downflow conditions so that the treatment of pollutants could be achieved under multiple aerobic, anoxic and anaerobic conditions sequentially in the same wetland bed. The performances of the baffled and conventional HSF constructed wetlands, planted and unplanted, in the removal of azo dye Acid Orange 7 (AO7) were compared at the hydraulic retention times (HRT) of 5, 3 and 2 days when treating domestic wastewater spiked with AO7 concentration of 300 mg/L. The planted baffled unit was found to achieve 100%, 83% and 69% AO7 removal against 73%, 46% and 30% for the conventional unit at HRT of 5, 3 and 2 days, respectively. Longer flow path provided by baffled wetland units allowed more contact of the wastewater with the rhizomes, microbes and micro-aerobic zones resulting in relatively higher oxidation reduction potential (ORP) and enhanced performance as kinetic studies revealed faster AO7 biodegradation rate under aerobic condition. In addition, complete mineralization of AO7 was achieved in planted baffled wetland unit due to the availability of a combination of aerobic, anoxic and anaerobic conditions.

  8. Efficiency of a Photoreactor Packed with Immobilized Titanium Dioxide Nanoparticles in the Removal of Acid Orange 7.

    Science.gov (United States)

    Sheidaei, Behnaz; Behnajady, Mohammad A

    2016-05-01

    In this paper, the removal efficiency of Color Index Acid Orange 7 (AO7) as a model contaminant was investigated in a batch-recirculated photoreactor packed with immobilized titanium dioxide type P25 nanoparticles on glass beads. The effects of different operational parameters such as the initial concentration of AO7, the volume of solution, the volumetric flowrate, and the light source power in the photoreactor were investigated. The results indicate that the removal percent increased with the rise in volumetric flowrate and power of the light source, but decreased with the rise of the initial concentration of AO7 and the volume of solution. The AO7 degradation was followed through total organic carbon, gas chromatography/mass spectroscopy (GC/MS), and mineralization products analysis. The ammonium and sulfate ions were analyzed as mineralization products of nitrogen and sulfur heteroatoms, respectively. The results of GC/MS revealed the production of 1-indanone, 1-phthalanone, and 2-naphthalenol as intermediate products for the removal of AO7 in this process.

  9. Preparation, characterization of a ceria loaded carbon nanotubes nanocomposites photocatalyst and degradation of azo dye Acid Orange 7

    Directory of Open Access Journals (Sweden)

    Wen Tao

    2016-06-01

    Full Text Available A ceria loaded carbon nanotubes (CeO2/CNTs nanocomposites photocatalyst was prepared by chemical precipitation, and the preparation conditions were optimized using an orthogonal experiment method. HR-TEM, XRD, UV-Vis/DRS, TGA and XPS were used to characterize the photocatalyst. Nitrogen adsorption-desorption was employed to determine the BET specific surface area. The results indicated that the photocatalyst has no obvious impurities. CeO2 was dispersed on the carbon nanotubes with a good loading effect and high loading efficiency without agglomeration. The catalyst exhibits a strong ability to absorb light in the ultraviolet region and some ability to absorb light in the visible light region. The CeO2/CNTs nanocomposites photocatalyst was used to degrade azo dye Acid Orange 7 (40 mg/L. The optical decolorization rate was 66.58% after xenon lamp irradiation for 4 h, which is better than that of commercial CeO2 (43.13%. The results suggested that CeO2 loading on CNTs not only enhanced the optical decolorization rate but also accelerated the separation of CeO2/CNTs and water.

  10. Adsorption Kinetics of Acid Orange 7 on Nano-CeO2-TiO2 in Water.

    Science.gov (United States)

    Song, Xiaozhen; Zhao, Bin; Gu, Mingjie; Li, Ruixing

    2015-09-01

    To investigate the application of nano-CeO2-TiO2 as a sorbent in wastewater treatment, CeO2-TiO2 powder was prepared by the solvothermal method and then characterized. The adsorption kinetics of the adsorption of acid orange 7 (AO7) on CeO2-TiO2 were investigated under various conditions, such as initial concentration, temperature, and pH of the AO7 solution. Kinetic analyses were conducted with both Lagergren pseudo-first and pseudo-second order models. The results showed that the CeO2-TiO2 powder was composed of cubic CeO2 and anatase TiO2 with a specific surface area of 140.42 m2 x g(-1). The adsorption capacity of AO7 on CeO2-TiO2 increased with increasing starting concentration of AO7, but decreased with increasing temperature. The most favorable pH range of the A07 solution was 3-8 for the adsorption of AO7 on CeO2-TiO2. The results revealed that the adsorption kinetics of AO7 on CeO2-TiO2 matched the pseudo-second order model very well. The results indicate that CeO2-TiO2 has a potential application in the removal of AO7 from wastewater.

  11. Removal of Congo Red and Acid Yellow 36 Dye Using Orange Peel and Rice Husk as Absorbent

    Directory of Open Access Journals (Sweden)

    K. N. Ranjini

    2014-06-01

    Full Text Available Many researchers have identified the capability of agricultural wastes as absorbents to remove different types of pollutants including dyes. This study represents the use of orange peel (OP and rice husk (RH to remove two types of dye, Congo Red (CR and Acid Yellow 36 (AY 36 dye and provides simple comparison between granular form of OP and RH and activated form of OP and RH. Both types of dyes are toxic and can cause severe problems to the environment. Factor such as absorbent dosage was studied. Batch absorption studies were conducted at 27˚C with constant stirring at 150 rpm for 2 hours and absorbent dosage of 0.2 to 1.0 g. The results showed that the activated form of OP and RH had the highest removal percentage of CR and AY 36 dyeswhich were up to 100% removal. This study indicates that OP and RH could be employed as low cost materials for the removal of textile dyes from effluents.

  12. Decolourisation of Acid Orange 7 recalcitrant auto-oxidation coloured by-products using an acclimatised mixed bacterial culture.

    Science.gov (United States)

    Bay, Hui Han; Lim, Chi Kim; Kee, Thuan Chien; Ware, Ismail; Chan, Giek Far; Shahir, Shafinaz; Ibrahim, Zaharah

    2014-03-01

    This study focuses on the biodegradation of recalcitrant, coloured compounds resulting from auto-oxidation of Acid Orange 7 (AO7) in a sequential facultative anaerobic-aerobic treatment system. A novel mixed bacterial culture, BAC-ZS, consisting of Brevibacillus panacihumi strain ZB1, Lysinibacillus fusiformis strain ZB2, and Enterococcus faecalis strain ZL bacteria were isolated from environmental samples. The acclimatisation of the mixed culture was carried out in an AO7 decolourised solution. The acclimatised mixed culture showed 98 % decolourisation within 2 h of facultative anaerobic treatment using yeast extract and glucose as co-substrate. Subsequent aerobic post treatment caused auto-oxidation reaction forming dark coloured compounds that reduced the percentage decolourisation to 73 %. Interestingly, further agitations of the mixed culture in the solution over a period of 48 h significantly decolourise the coloured compounds and increased the decolourisation percentage to 90 %. Analyses of the degradation compounds using UV-visible spectrophotometer, Fourier transform infrared spectroscopy (FTIR) and high performance liquid chromatography (HPLC) showed complete degradation of recalcitrant AO7 by the novel BAC-ZS. Phytotoxicity tests using Cucumis sativus confirmed the dye solution after post aerobic treatment were less toxic compared to the parent dye. The quantitative real-time PCR revealed that E. faecalis strain ZL was the dominant strain in the acclimatised mix culture.

  13. The use of artificial neural network for modeling the decolourization of acid orange 7 solution of industrial by ozonation process

    Science.gov (United States)

    Fatimah, S.; Wiharto, W.

    2017-02-01

    Acid Orange 7 (AO7) is one of the synthetic dye in the dyeing process in the textile industry. The use of this dye can produce wastewater which will be endangered if not treated well. Ozonation method is one technique to solve this problem. Ozonation is a waste processing techniques using ozone as an oxidizing agent. Variables used in this research is the ozone concentration, the initial concentration of AO7, temperature, and pH. Based on the experimental result that the optimum value decolourization percentage is 80% when the ozone concentration is 560 mg/L, the initial concentration AO7 is 14 mg/L, the temperature is 390 °C, and pH is 7,6. Decolourization efficiency of experimental results and predictions successfully modelled by the neural network architecture. The data used to construct a neural network architecture quasi newton one step secant as many as 31 data. A comparison between the predicted results of the designed ANN models and experiment was conducted. From the modeling results obtained MAPE value of 0.7763%. From the results of this artificial neural network architecture obtained the optimum value decolourization percentage in 80,64% when the concentration of ozone is 550 mg/L, the initial concentration AO7 is 11 mg/L, the temperature is 41 °C, and the pH is 7.9.

  14. Equilibrium, kinetic and thermodynamic studies of acid Orange 52 dye biosorption by Paulownia tomentosa Steud. leaf powder as a low-cost natural biosorbent.

    Science.gov (United States)

    Deniz, Fatih; Saygideger, Saadet D

    2010-07-01

    The biosorption of Acid Orange 52 onto the leaf powder of Paulownia tomentosa Steud. was studied in a batch adsorption system to estimate the equilibrium, kinetic and thermodynamic parameters as a function of solution pH, biosorbent concentration, dye concentration, biosorbent size, temperature and contact time. The Langmuir, Freundlich and Temkin isotherm models were used for modeling the biosorption equilibrium. The experimental equilibrium data could be well interpreted by the Temkin and Langmuir isotherms with maximum adsorption capacity of 10.5 mg g(-1). In order to state the sorption kinetics, the fits of pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion kinetic models were investigated. It was obtained that the biosorption process followed the pseudo-second order rate kinetics. Thermodynamic studies indicated that this system was exothermic process. The results revealed that P. tomentosa leaf powder could be an efficient biosorbent for the treatment of wastewater containing Acid Orange 52.

  15. Effects of Lactic Acid Fermentation on the Retention of Β-Carotene Content in Orange Fleshed Sweet Potatoes

    Directory of Open Access Journals (Sweden)

    Benard O. Oloo

    2014-04-01

    Full Text Available This study aimed to establish the effects of lactic fermentation on the levels of β-carotene in selected  orange fleshed sweet potato (OFSP varieties from Kenya.  Furthermore,it sought to demonstrate fermentation as a potential process for making new products from sweet potato with enhanced nutraceutical attributes. The varieties (Zapallo, Nyathiodiewo and SPK004/06 were fermented with Lactobacillus plantarum MTCC 1407 at 25 ± 2°C for 48 h and kept for 28 days to make lacto-pickles. During fermentation both analytical [pH, titratable acidity (TA, lactic acid (LA, starch, total sugar, reducing sugar (g/kg roots, texture (N/m2, β-carotene (mg/kg roots] and sensory (texture, taste, flavour and after taste attributes of sweet potato lacto-juice were evaluated. Process conditions were optimized by varying brine levels, with fermentation time. A UV-visible spectrophotometer was used to identify and quantify β-carotene. Any significant variations (p < 0.05 in analytical attributes between the fermented and unfermented samples (pH, LA, TA and β-carotene concentration of lacto-pickles, prepared from the potato roots, were assessed. The study reported a final composition of 156.49mg/kg, 0.53mg/kg, 0.3N/m2, 1.3g/kg, 5.86g/kg, 0.5g/kg and 5.86g/kg for β-carotene, Ascorbic acid, texture; Starch, total sugars, LA and TA respectively, and a pH of 3.27. The fermented products were subjected to flavour profiling by a panel. The product sensory scores were 1.5 to 2.5 on a 5 point hedonic scale, ranging from dislike slightly to like much. The products with brine levels at 4 and 6% were most preferred. The retention of β-carotene was 93.97%. This demonstrated lactic acid fermentation as a better method for processing OFSP as the main nutritional attributes are retained. The final product was resistant to spoilage microorganisms after 28 days of fermentation. Further preservation could be obtained by addition of sodium metabisulphite. In conclusion, Lactic

  16. Biosorption and biodegradation of Acid Orange 7 by Enterococcus faecalis strain ZL: optimization by response surface methodological approach.

    Science.gov (United States)

    Lim, Chi Kim; Bay, Hui Han; Aris, Azmi; Abdul Majid, Zaiton; Ibrahim, Zaharah

    2013-07-01

    Reactive dyes account for one of the major sources of dye wastes in textile effluent. In this study, decolorization of the monoazo dye, Acid Orange 7 (AO7) by the Enterococcus faecalis strain ZL that isolated from a palm oil mill effluent treatment plant has been investigated. Decolorization efficiency of azo dye is greatly affected by the types of nutrients and the size of inoculum used. In this work, one-factor-at-a-time (method and response surface methodology (RSM) was applied to optimize these operational factors and also to study the combined interaction between them. Analysis of AO7 decolorization was done using Fourier transform infrared (FTIR) spectroscopy, desorption study, UV-Vis spectral analysis, field emission scanning electron microscopy (FESEM), and high performance liquid chromatography (HPLC). The optimum condition via RSM for the color removal of AO7 was found to be as follows: yeast extract, 0.1% w/v, glycerol concentration of 0.1% v/v, and inoculum density of 2.5% v/v at initial dye concentration of 100 mg/L at 37 °C. Decolorization efficiency of 98% was achieved in only 5 h. The kinetic of AO7 decolorization was found to be first order with respect to dye concentration with a k value of 0.87/h. FTIR, desorption study, UV-Vis spectral analysis, FESEM, and HPLC findings indicated that the decolorization of AO7 was mainly due to the biosorption as well as biodegradation of the bacterial cells. In addition, HPLC analyses also showed the formation of sulfanilic acid as a possible degradation product of AO7 under facultative anaerobic condition. This study explored the ability of E. faecalis strain ZL in decolorizing AO7 by biosorption as well as biodegradation process.

  17. Simultaneous determination of banned acid orange dyes and basic orange dyes in foodstuffs by liquid chromatography-tandem electrospray ionization mass spectrometry via negative/positive ion switching mode.

    Science.gov (United States)

    Fang, Guozhen; Wu, Yu; Dong, Xiaomeng; Liu, Cuicui; He, Shaoyuan; Wang, Shuo

    2013-04-24

    Simultaneous detection of two classes of dyes possessing different chemical properties is difficult. In this study, through negative/positive ion switching mode, simultaneous determination of four typical acid orange dyes and three typical basic orange dyes was achieved by a single high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, and the analytical efficiency of multiresidues identification was greatly improved. To enhance detection sensitivity, the sample pretreatment conditions and HPLC-MS/MS determining conditions were carefully optimized. Under optimal conditions, good linearity was obtained over the range of 5-500 μg L(-1) with a correlation coefficient (R(2)) >0.9998. Limits of detection (LODs) and limits of quantification (LOQs) of the seven dyes were 0.5-3.0 and 2.0-6.0 μg kg(-1), respectively. The recoveries of the seven dyes in soybean products and marinated eggs were 74-126% with relative standard deviations (RSDs) of 2.22-25.4%, suggesting the developed method is promising for the accurate quantification of the seven dyes at trace levels in foods.

  18. Efficient degradation of Acid Orange 7 in aqueous solution by iron ore tailing Fenton-like process.

    Science.gov (United States)

    Zheng, Jianming; Gao, Zhanqi; He, Huan; Yang, Shaogui; Sun, Cheng

    2016-05-01

    An effective method based on iron ore tailing Fenton-like process was studied for removing an azo dye, Acid Orange 7 (AO7) in aqueous solution. Five tailings were characterized by X-ray fluorescence spectroscope (XFS), Brunner-Emmet-Teller (BET) measurement, and Scanning Electron Microscope (SEM). The result of XFS showed that Fe, Si and Ca were the most abundant elements and some toxic heavy metals were also present in the studied tailings. The result of BET analysis indicated that the studied tailings had very low surface areas (0.64-5.68 m(2) g(-1)). The degradation efficiencies of AO7 were positively correlated with the content of iron oxide and cupric oxide, and not related with the BET surface area of the tailings. The co-existing metal elements, particularly Cu, might accelerate the heterogeneous Fenton-like reaction. The effects of other parameters on heterogeneous Fenton-like degradation of AO7 by a converter slag iron tailing (tailing E) which contains highest iron oxide were also investigated. The tailing could be reused 10 times without significant decrease of the catalytic capacity. Very low amount of iron species and almost undetectable toxic elements were leached in the catalytic degradation of AO7 by the tailing E. The reaction products were identified by gas chromatography-mass spectrometry and a possible pathway of AO7 degradation was proposed. This study not only provides an effective method for removing azo dyes in polluted water by employing waste tailings as Fenton-like catalysts, but also uses waste tailings as the secondary resource. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Response of 'Nagpur' mandarin, 'Mosambi' sweet orange and 'Kagzi' acid lime to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ladaniya, M.S. E-mail: mslngp@nagpur.dot.net.in; Singh, Shyam; Wadhawan, A.K

    2003-07-01

    The effects of irradiation dose and refrigerated storage conditions on 'Nagpur' mandarin (Citrus reticulata Blanco), 'Mosambi' sweet orange (Citrus sinensis Osbeck) and 'Kagzi' acid lime (Citrus aurantifolia Swingle) were investigated. Mature fruits of these three species were treated with 0, 0.25, 0.5, 1 and 1.5 kGy radiation. 'Nagpur' mandarin and 'Mosambi' sweet oranges were stored at 6-7 deg. C and 90-95% r.h. for 75 and 90 days, respectively, while 'Kagzi' acid limes were stored at 8{+-}1 deg. C and 90-95% r.h. for 90 days. Physico-chemical parameters, sensory attributes and respiration rate were measured besides losses and disorders. In 'Nagpur' mandarin, radiation dose upto 1.5 kGy did not cause any rind disorder. Radiation treatments did not reduce the extent of decay. Penicillium rot was delayed in fruit treated with 1.5 kGy, while it appeared early in 0 kGy. Irradiation doses were ineffective to control rots due to Botryodiplodia theobromae and Alternaria citri. Doses upto 1.5 kGy did not cause any significant effect on fruit firmness and juice content; however, total soluble solids increased, while titratable acidity and vitamin 'C' content decreased. Texture and flavour scores as recorded after a week, were not affected by irradiation except in 1.5 kGy. In 'Mosambi' sweet orange, radiation treatments caused peel disorder in the form of brown sunken areas after 90 days and reduced fruit firmness, acidity and vitamin C content. The TSS content was higher in treated fruit. Flavour and texture were not affected by the doses of irradiation used. In treated acid limes (mature yellow), weight loss and decay were higher than untreated fruit (0 kGy) although difference was non-significant. Juice, TSS, titratable acidity and vitamin C contents were significantly less in treated fruit than in 0 kGy. Texture and flavour scores were also less in treated fruit than in 0 kGy. The

  20. Copper(II and lead(II complexation by humic acid and humic-like ligands

    Directory of Open Access Journals (Sweden)

    IVANA KOSTIĆ

    2011-09-01

    Full Text Available The stability of metal–humate complexes is an important factor determining and predicting speciation, mobility and bioavailability of heavy metals in the environment. A comparative investigation of the complexation of Cu(II and Pb(II with humic acid and humic-like ligands, such as benzoic and salicylic acid, was performed. The analysis was realized at pH 4.0, a temperature of 25 °C and at an ionic strength of 0.01 mol dm-3 (NaCl using the Schubert ion-exchange method and its modified form. The stability constants were calculated from the experimental data by the Schubert method for complexes with benzoic and humic acid. A modified Schubert method was used for the determination of the stability constants of the complexes with salicylic acid. It was found that Cu(II and Pb(II form mononuclear complexes with benzoic and humic acid while with salicylic acid both metals form polynuclear complexes. The results indicate that Pb(II has a higher binding ability than Cu(II to all the investigated ligands. The Cu(II–salicylate and Pb(II–salicylate complexes showed noticeable higher stability constants compared with their complexes with humic acid, while the stabilities of the complexes with benzoic acid differed less. Salicylic and benzoic acids as humic-like ligands can be used for setting the range of stability constants of humic complexes with Cu(II and Pb(II.

  1. The decolorization and mineralization of Acid Orange 6 azo dye in aqueous solution by advanced oxidation processes: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Hsing, H.-J. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China); Chiang, P.-C. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China)]. E-mail: pcchiang@ntu.edu.tw; Chang, E.-E. [Department of Biochemistry, Taipei Medical University, 25 Wu-Shin Street, Taipei 106, Taiwan (China); Chen, M.-Y. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China)

    2007-03-06

    The comparison of different advanced oxidation processes (AOPs), i.e. ultraviolet (UV)/TiO{sub 2}, O{sub 3}, O{sub 3}/UV, O{sub 3}/UV/TiO{sub 2}, Fenton and electrocoagulation (EC), is of interest to determine the best removal performance for the destruction of the target compound in an Acid Orange 6 (AO6) solution, exploring the most efficient experimental conditions as well; on the other hand, the results may provide baseline information of the combination of different AOPs in treating industrial wastewater. The following conclusions can be drawn: (1) in the effects of individual and combined ozonation and photocatalytic UV irradiation, both O{sub 3}/UV and O{sub 3}/UV/TiO{sub 2} processes exhibit remarkable TOC removal capability that can achieve a 65% removal efficiency at pH 7 and O{sub 3} dose = 45 mg/L; (2) the optimum pH and ratio of [H{sub 2}O{sub 2}]/[Fe{sup 2+}] found for the Fenton process, are pH 4 and [H{sub 2}O{sub 2}]/[Fe{sup 2+}] = 6.58. The optimum [H{sub 2}O{sub 2}] and [Fe{sup 2+}] under the same HF value are 58.82 and 8.93 mM, respectively; (3) the optimum applied voltage found in the EC experiment is 80 V, and the initial pH will affect the AO6 and TOC removal rates in that acidic conditions may be favorable for a higher removal rate; (4) the AO6 decolorization rate ranking was obtained in the order of O{sub 3} < O{sub 3}/UV = O{sub 3}/UV/TiO{sub 2} < EC < Fenton; (5) the ranking of TOC removal efficiency of selected AOPs was in the order of O{sub 3} = Fenton < EC < O{sub 3}/UV < O{sub 3}/UV/TiO{sub 2} for 30 min of reaction time.

  2. Inactivation of Escherichia coli O157:H7, Salmonella enteritidis, and Listeria monocytogenes on apples, oranges, and tomatoes by lactic acid with hydrogen peroxide.

    Science.gov (United States)

    Venkitanarayanan, Kumar S; Lin, Chia-min; Bailey, Hannalore; Doyle, Michael P

    2002-01-01

    The objective of this study was to develop a practical and effective method for inactivating or substantially reducing Escherichia coli O157:H7, Salmonella Enteritidis, and Listeria monocytogenes on apples, oranges, and tomatoes. Apples, oranges, and tomatoes were spot-inoculated with five-strain mixtures of E. coli O157:H7, Salmonella Enteritidis, and L. monocytogenes near the stem end and were submerged in sterile deionized water containing 1.5% lactic acid plus 1.5% hydrogen peroxide for 15 min at 40 degrees C. Inoculated samples treated with sterile deionized water at the same temperature and for the same duration served as controls. The bacterial pathogens on fruits subjected to the chemical treatment were reduced by >5.0 log10 CFU per fruit, whereas washing in deionized water decreased the pathogens by only 1.5 to 2.0 log10 CFU per fruit. Furthermore, substantial populations of the pathogens survived in the control wash water, whereas no E. coli O157:H7, Salmonella Enteritidis, or L. monocytogenes cells were detected in the chemical treatment solution. The sensory and qualitative characteristics of apples treated with the chemical wash solution were not adversely affected by the treatment. It was found that the treatment developed in this study could effectively be used to kill E. coli O157:H7, Salmonella Enteritidis, and L. monocytogenes on apples, oranges, and tomatoes at the processing or packaging level.

  3. Chromate enhanced visible light driven TiO{sub 2} photocatalytic mechanism on Acid Orange 7 photodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yeoung-Sheng; Shen, Jyun-Hong [Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology (YunTech), Douliou, Yunlin, Taiwan (China); Horng, Jao-Jia, E-mail: horngjj@gmail.com [Department of Safety, Health and Environmental Engineering, National Yunlin University of Science and Technology (YunTech), Douliou, Yunlin, Taiwan (China)

    2014-06-01

    Highlights: • Photocatalysis of Cr(VI) and TiO{sub 2} were studied by ESR analysis on DMPO-OH signals. • Mechanism of Cr(VI)-enhanced by visible light was different from that by UV. • O{sub 2} adsorbed on TiO{sub 2} surfaces could react with Cr(VI) to lower photoenergy needed. • Even by UV, no TiO{sub 2} photocatalysis was observed without O{sub 2} solution. • Visible light and Cr(VI) redox reaction could activate TiO{sub 2} and would yield ·OH. - Abstract: When hexavalent chromium (Cr(VI)) is added to a TiO{sub 2} photocatalytic reaction, the decolorization and mineralization efficiencies of azo dyes Acid Orange 7 (AO7) are enhanced even though the mechanism is unclear. This study used 5,5-dimethyl-L-pyrroline-N-oxide (DMPO) as the scavenger and the analysis of Electron Spin Resonance (ESR) to investigate this enhancement effect by observing the hydroxyl radical (·OH) generation of the Cr(VI)/TiO{sub 2} system under UV and visible light (Vis) irradiation. With Cr(VI), the decolorization efficiencies were approximately 95% and 62% under UV and Vis, and those efficiencies were 25% less in the absence of Cr(VI). The phenomena of the DMPO-OH signals during the ESR analysis under Vis 405 and 550 nm irradiation were obviously the enhancement effects of Cr(VI) in aerobic conditions. In anoxic conditions, the catalytic effects of Cr(VI) could not be achieved due to the lack of a redox reaction between Cr(VI) and the adsorbed oxygen at the oxygen vacancy sites on the TiO{sub 2} surfaces{sub .} The results suggest that by introducing the agents of redox reactions such as chromate ions, we could lower the photoenergy of TiO{sub 2} needed and allow Vis irradiation to activate photocatalysis.

  4. Formic acid enhanced effective degradation of methyl orange dye in aqueous solutions under UV-Vis irradiation.

    Science.gov (United States)

    Wang, Jingjing; Bai, Renbi

    2016-09-15

    Developing efficient technologies to treat recalcitrant organic dye wastewater has long been of great research and practical interest. In this study, a small molecule, formic acid (FA), was applied as a process enhancer for the degradation of methyl orange (MO) dye as a model recalcitrant organic pollutant in aqueous solutions under the condition of UV-Vis light irradiation and air aeration at the ambient temperature of 25 °C. It was found that the decolouration of the dye solutions can be rapidly achieved, reducing the time, for example, from around 17.6 h without FA to mostly about less than 2 h with the presence of FA. The mineralization rate of MO dye reached as high as 81.8% in 1.5 h in the case of initial MO dye concentration at 25 mg L(-1), which is in contrast to nearly no mineralization of the MO dye for a similar system without the FA added. The study revealed that the generation of the H2O2 species in the system was enhanced and the produced OH radicals effectively contributed to the degradation of the MO dye. Process parameters such as the initial concentration of MO dye, FA dosage and solution pH were all found to have some effect on the degradation efficiency under the same condition of UV-Vis light irradiation and air aeration. The MO dye degradation performance was found to follow a first-order reaction rate to the MO dye concentration in most cases and there existed a positive correlation between the reaction rate constant and the initial FA concentration. Compared to the traditional H2O2/UV-Vis oxidation system, the use of FA as a process-enhancing agent can have the advantages of low cost, easy availability, and safe to use. The study hence demonstrates a promising approach to use a readily available small molecule of FA to enhance the degradation of recalcitrant organic pollutants, such as MO dye, especially for their pre-treatment.

  5. Photo catalytic degradation of organic dyes under solar irradiation: oxidation of Methyl-organe and orange II in aqueous suspension of titanium dioxide powder

    Energy Technology Data Exchange (ETDEWEB)

    Augugliaron, V.; Baiocchi, C.; Bianco Prevot, A.; Brussino, M. c.; Caceres Vazquez, J.; Garcia-Lopez, E.; Loddo, V.; Malato Rodriguez, S.; Marci, G.; Palmisano, L.; Pramauro, E.

    2001-07-01

    The photocatalytic oxidation of methyl-orange (C{sub 1}4H{sub 1}4N{sub 3}SO{sub 3}Na) and arange II (C{sub 1}6H{sub 1}1N{sub 2}SO{sub 4}Na) dyes was carried out in aqueous suspensions of polycrystalline TiO{sub 2} (anatase) irradiated by sunlight. The influence of th epresence of strong oxidant (H{sub 2}O{sub 2}S{sub 2}O{sub 8}''2) and ionic )Cl, SO{sub 4}''2) species on the process was studied. The dependende of dye photooxidation rate on the following parameters: (i) substrate concentration: (ii) catalyst amount: and (iii) pH was alos investigated. At the used experimental conditions the substrate photooxidation rate follows a pseudo-first order kinetics with respect to the substrate concentration. The presence of S{sub 2}O{sub 8}''2 enhances the reaction rate more that when H{sub 2}O{sub 2} was added. (Author) 20 refs.

  6. 利用乳酸菌发酵生产脐橙果酱的工艺研究%Preparation of Navel Orange Jam by Fermentation of Lactic Acid Bacteria

    Institute of Scientific and Technical Information of China (English)

    卫娜; 徐曼

    2012-01-01

    The process conditions of a navel orange jam were investigated in this paper, in which navel orange and its peels were used as raw material and fermented by lactic acid bacteria. The influence on the quality of navel orange jam was investigated and the optimum conditions were obtained by orthogonal experiments as following: fermentation time 24 h, navel orange peel-orange ratio 1:4 and custer sugar dosage 40%. The navel orange jam was prepared with golden yellow color, good flowing property and a moderately sweet and acid flavor.%以脐橙果肉和脐橙皮为原料,利用乳酸菌发酵来研制脐橙果酱的制作工艺.通过单因素试验研究各因素对脐橙果酱品质的影响,正交优化确定了脐橙果酱的最佳工艺务件:发酵时间24h,脐橙皮和果肉的添加比例为1∶4,白砂糖的添加量为40%.制得的脐橙果酱颜色金黄,流散性好,酸甜可口,均匀细腻.

  7. Visible light degradation of Orange II using xCu{sub y}O{sub z}/TiO{sub 2} heterojunctions

    Energy Technology Data Exchange (ETDEWEB)

    Helaili, N. [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry, U.S.T.H.B., BP 32, 16111, El-Alia, Algiers (Algeria); Bessekhouad, Y., E-mail: ybessekhouad@yahoo.fr [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry, U.S.T.H.B., BP 32, 16111, El-Alia, Algiers (Algeria); National Veterinary School, BP 161-El Harrach, Algiers (Algeria); Bouguelia, A.; Trari, M. [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry, U.S.T.H.B., BP 32, 16111, El-Alia, Algiers (Algeria)

    2009-08-30

    Cu{sub 2}O/TiO{sub 2}, Cu/Cu{sub 2}O/TiO{sub 2} and Cu/Cu{sub 2}O/CuO/TiO{sub 2} heterojunctions were prepared and studied for their potential application as photocatalysts able to induce high performance under visible light. Orange II was used as a representative dye molecule. The effect of the amount and composition of the photosensitizers toward the activation of TiO{sub 2} was studied. In each case, the global mechanism of Inter Particle Electrons Injection (IPEI) was discussed. The highest photocatalytic activity was observed for the system Cu/Cu{sub 2}O/CuO (MB2 catalyst) under visible light (t{sub 1/2} = 24 min, k = 159.7 x 10{sup -3} min{sup -1}) and for the heterojunction cascade Cu/Cu{sub 2}O/CuO/TiO{sub 2} (MB2 (50%)/TiO{sub 2}) under UV-vis light (t{sub 1/2} = 4 min, k = 1342 x 10{sup -3} min{sup -1}). In the last case, the high performance was attributed firstly to the electromotive forces developed under this configuration in which CuO energy bands mediate the electrons transfer from Cu{sub 2}O to TiO{sub 2}. The formation of monobloc sensitizers also accounts for the decrease of the probability of the charges lost. It was demonstrated that 'Cu{sub 2}O/CuO' governs the capability of the heterojunction cascade and Cu does not play a significant role regardless of the heterojunction cascade efficiency. The electrical energy consumption per order of magnitude for photocatalytic degradation of Orange II was investigated for some representative catalytic systems. Visible/MB2 and UV/vis MB2 (50%)/TiO{sub 2} exhibited respectively 0.340 and 0.05 kWh m{sup -3} demonstrating the high efficiency of the systems.

  8. Improvement of Orange II Photobleaching by Moderate Ga3+ Doping of Titania and Detrimental Effect of Structural Disorder on Ga Overloading

    Directory of Open Access Journals (Sweden)

    Václav Štengl

    2014-01-01

    Full Text Available Highly photoactive Ga3+-doped anatase modification of titania was prepared by homogeneous hydrolysis of aqueous solutions mixture of titanium oxo-sulphate TiOSO4 and gallium(III nitrate with urea. Incorporation of Ga3+ into the anatase lattice has a clear positive effect on the photocatalytic activity under UV and Vis light irradiation up to a certain extent of Ga. Ga3+ doping decreased the size of the crystallites, increased surface area, and affected texture of the samples. Higher amount of gallium leads to the formation of a nondiffractive phase, probably photocatalytically inactive. The titania sample with 2.18 wt.% Ge3+ had the highest activity during the photocatalysed degradation in the UV and visible light regions; the total bleaching of dye Orange II was achieved within 29 minutes. Ga concentration larger than 5% (up to 15% significantly inhibited the growth of the anatase crystal domains which formed the nondiffractive phase content and led to remarkable worsening of the photobleaching efficiency.

  9. Synthesis and photocatalytic performance of reduced graphene oxide-TiO2 nanocomposites for orange II degradation under UV light irradiation.

    Science.gov (United States)

    Li, Tengfei; Wang, Tiecheng; Qu, Guangzhou; Liang, Dongli; Hu, Shibin

    2017-03-30

    To enhance the photocatalytic activity of TiO2, reduced graphene oxide-TiO2 (RGO-TiO2) composites with sandwich-like structure were synthesized using a simple solvothermal method. The morphology, crystalline information, and structural property of the photocatalyst were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Fourier transmission infrared spectroscopy. The photocatalytic performances of the RGO-TiO2 composites were evaluated by the degradation of orange II (AO7) in water under UV light irradiation. The results showed that the RGO-TiO2 composites exhibited much higher photocatalytic activity than TiO2 and that the removal efficiency of AO7 could reach above 95% only after 20 min of UV light irradiation under the optimum condition. The improved photocatalytic activity might be attributed to the improved charge transfer and significant separation of the photoinduced electrons and holes in the presence of a two-dimensional graphene network. The results of recycling experiments show that RGO-TiO2 composites have a high photostability, which is expected in the practical application. Radical trapping experiments indicated that ·OH plays a crucial role in the process of AO7 degradation.

  10. Photodegradation of methyl orange and photoinactivation of bacteria by visible light activation of persulphate using a tris(2,2'-bipyridyl)ruthenium(II) complex.

    Science.gov (United States)

    Subramanian, Gokulakrishnan; Parakh, Priyadarshini; Prakash, Halan

    2013-03-01

    Persulphate is an emerging oxidant in the field of advanced oxidation processes for the degradation of environmentally persistent organic compounds. The present study shows that visible light activation of persulphate (2 mM) using tris(2,2'-bipyridyl)ruthenium(II) (complex 1) (1 μM) caused rapid degradation (98%) of model azo dye methyl orange (MO) (12 mg L(-1)) with significant mineralization (76%), and also complete inactivation of both Gram negative and positive bacteria (∼10(7) CFU mL(-1)). BacLight LIVE/DEAD assay, scanning electron microscopy and genomic DNA analysis revealed cell membrane damage and loss of chromosomal DNA, indicating oxidative stress caused to E. coli during photoinactivation. The effect of concentration of complex 1 : persulphate ratio and presence of inorganic ions (0.1 M), such as sodium hydrogen phosphate, sodium sulphate, and sodium hydrogen carbonate, on the photodegradation of MO and photoinactivation of E. coli were studied. In addition, the effect of the presence of the organic contaminant resorcinol on the photoinactivation of E. coli was also studied. Significant degradation of MO and complete inactivation of bacteria were observed in simulated ground water. The present study is the first to reveal that activation of persulphate using a visible light absorbing metal complex in aqueous media has the ability to cause degradation of organic contaminants as well as complete inactivation of bacteria.

  11. Copper(II) coordination polymers: tunable structures and a different activation effect of hydrogen peroxide for the degradation of methyl orange under visible light irradiation.

    Science.gov (United States)

    Liu, Lu; Wu, Dongqing; Zhao, Bei; Han, Xiao; Wu, Jie; Hou, Hongwei; Fan, Yaoting

    2015-01-21

    By tuning the synthesis conditions, based on a conformation-sensitive ligand, 1,4-bis(1,2,4-triazole-1-methylene)-2,3,5,6-tetramethyl benzene (btmx) and Cu(NO3)2·3H2O/CuCl2·2H2O, we have obtained three Cu(ii) coordination polymers with diverse structures, namely, {[Cu(btmx)2(H2O)]·2NO3}n (), {[Cu(btmx)2(Cl)2]·5H2O}n () and [Cu(btmx)(Cl)2]n (). Complex exhibits a novel 2D → 3D interpenetrating structure with a point symbol of 6(3). Complex features an irregular 2D grid with (4(4)·6(2)) topology. The structure of complex is a 1D double chain structure. The ultraviolet-visible absorption spectra and TG curves of these complexes are also presented and discussed. Moreover, under visible light, the coordination polymers , , and display a different activation effect of hydrogen peroxide (H2O2) for the photocatalytic decomposition of methyl orange (MO), which indicates that the coordination polymers may have bright prospects in the field of photocatalytic degradation of dyes.

  12. Competition from Cu(II), Zn(II) and Cd(II) in Pb(II) binding to Suwannee River Fulvic Acid

    NARCIS (Netherlands)

    Chakraborty, P.; Chakrabarti, C.L.

    2008-01-01

    This is a study of trace metal competition in the complexation of Pb(II) by well-characterized humic substances, namely Suwannee River Fulvic Acid (SRFA) in model solutions. It was found that Cu(II) seems to compete with Pb(II) for strong binding sites of SRFA when present at the same concentration

  13. Decolorization and degradation of Disperse Blue 79 and Acid Orange 10, by Bacillus fusiformis KMK5 isolated from the textile dye contaminated soil.

    Science.gov (United States)

    Kolekar, Yogesh M; Pawar, Shrikant P; Gawai, Kachru R; Lokhande, Pradeep D; Shouche, Yogesh S; Kodam, Kisan M

    2008-12-01

    The release of azo dyes into the environment is a concern due to coloration of natural waters and due to the toxicity, mutagenicity and carcinogenicity of the dyes and their biotransformation products. The dye degrading bacterial strain KMK 5 was isolated from the textile dyes contaminated soil of Ichalkaranji, Maharashtra, India. It was identified as Bacillus fusiformis based on the biochemical and morphological characterization as well as 16S rDNA sequencing. KMK 5 could tolerate and degrade azo dyes, Disperse Blue 79 (DB79) and Acid Orange 10 (AO10) under anoxic conditions. Complete mineralization of DB79 and AO10 at the concentration of 1.5g/l was observed within 48h. This degradation potential increased the applicability of this microorganism for the dye removal.

  14. EPOXYEICOSATRIENOIC ACID ANALOG ATTENUATES ANGIOTENSIN II HYPERTENSION AND KIDNEY INJURY

    Directory of Open Access Journals (Sweden)

    Md. Abdul Hye Khan

    2014-09-01

    Full Text Available Epoxyeicosatrienoic acids (EETs contribute to blood pressure regulation leading to the concept that EETs can be therapeutically targeted for hypertension and the associated end-organ damage. In the present study, we investigated anti-hypertensive and kidney protective actions of an EET analog, EET-B in angiotensin II (ANG II-induced hypertension. EET-B was administered in drinking water for 14 days (10mg/kg/d and resulted in a decreased blood pressure elevation in ANG II hypertension. At the end of the two-week period, blood pressure was 30 mmHg lower in EET analog-treated ANG II hypertensive rats. The vasodilation of mesenteric resistance arteries to acetylcholine was impaired in ANG II hypertension; however, it was improved with EET-B treatment. Further, EET-B protected the kidney in ANG II hypertension as evidenced by a marked 90% decrease in albuminuria and 54% decrease in nephrinuria. Kidney histology demonstrated a decrease in renal tubular cast formation in EET analog-treated hypertensive rats. In ANG II hypertension, EET-B treatment markedly lowered renal inflammation. Urinary monocyte chemoattractant protein-1 excretion was decreased by 55% and kidney macrophage infiltration was reduced by 52% with EET-B treatment. Overall, our results demonstrate that EET-B has anti-hypertensive properties, improves vascular function, and decreases renal inflammation and injury in ANG II hypertension.

  15. Epoxyeicosatrienoic acid analog attenuates angiotensin II hypertension and kidney injury.

    Science.gov (United States)

    Khan, Abdul Hye; Falck, John R; Manthati, Vijaya L; Campbell, William B; Imig, John D

    2014-01-01

    Epoxyeicosatrienoic acids (EETs) contribute to blood pressure regulation leading to the concept that EETs can be therapeutically targeted for hypertension and the associated end organ damage. In the present study, we investigated anti-hypertensive and kidney protective actions of an EET analog, EET-B in angiotensin II (ANG II)-induced hypertension. EET-B was administered in drinking water for 14 days (10 mg/kg/d) and resulted in a decreased blood pressure elevation in ANG II hypertension. At the end of the two-week period, blood pressure was 30 mmHg lower in EET analog-treated ANG II hypertensive rats. The vasodilation of mesenteric resistance arteries to acetylcholine was impaired in ANG II hypertension; however, it was improved with EET-B treatment. Further, EET-B protected the kidney in ANG II hypertension as evidenced by a marked 90% decrease in albuminuria and 54% decrease in nephrinuria. Kidney histology demonstrated a decrease in renal tubular cast formation in EET analog-treated hypertensive rats. In ANG II hypertension, EET-B treatment markedly lowered renal inflammation. Urinary monocyte chemoattractant protein-1 excretion was decreased by 55% and kidney macrophage infiltration was reduced by 52% with EET-B treatment. Overall, our results demonstrate that EET-B has anti-hypertensive properties, improves vascular function, and decreases renal inflammation and injury in ANG II hypertension.

  16. ORANGE: RANGE OF BENEFITS

    OpenAIRE

    Parle Milind; Chaturvedi Dev

    2012-01-01

    No wonder that oranges are one of the most popular fruits in the world. Orange (citrus sinensis) is well known for its nutritional and medicinal properties throughout the world. From times immemorial, whole Orange plant including ripe and unripe fruits, juice, orange peels, leaves and flowers are used as a traditional medicine. Citrus sinensis belongs to the family Rutaceae. The fruit is a fleshy, indehiscent, berry that ranges widely in size from 4 cm to 12 cm. The major medicinal proper...

  17. 二氧化锰对酸性甲基橙作用机制的研究%Study on Mechanisms of the Action of Manganese Dioxide to Acidity Methyl-Orange

    Institute of Scientific and Technical Information of China (English)

    张乃东; 彭永臻

    2007-01-01

      The process of MnO2 adsorbing acidity methyl-orange was studied by using UV-visible spectra、IR spectra and mass spectrum. The results showed that oxidation and reduction reactions do occur between MnO2 and acidity methyl-orange besides the chemic adsorption. During the reactions, colorless and soluble Mn(Ⅲ) complex compound is generated which is instable and changes into salmon pink materials gradually. Pure MnO2 adsorption shows lower removal efficiency on methyl-orange, and the final decolorization rate on 25mg/L methyl-orange liquid sample is only 79.5%.%  用UV-Vis、IR和MS对二氧化锰吸附酸性甲基橙的过程的研究结果表明,在二氧化锰和酸性甲基橙之间除了化学性吸附之外,还有氧化还原反应发生,生成了无色的可溶于水的Mn(Ⅲ)络合物,该络合物不稳定,逐渐转化成浅橙色的物质.单纯的二氧化锰吸附法对甲基橙的去除效果并不理想,25mg/L甲基橙水样的最终色度去除率为79.5%.

  18. Comparing equivalent thermal, high pressure and pulsed electric field processes for mild pasteurization of orange juice: Part II: Impact on specific chemical and biochemical quality parameters

    NARCIS (Netherlands)

    Vervoort, L.; Plancken, van der I.; Grauwet, T.; Timmermans, R.A.H.; Mastwijk, H.C.; Matser, A.M.; Hendrickx, M.E.; Loey, van A.

    2011-01-01

    The impact of thermal, high pressure (HP) and pulsed electric field (PEF) processing for mild pasteurization of orange juice was compared on a fair basis, using processing conditions leading to an equivalent degree of microbial inactivation. Examining the effect on specific chemical and biochemical

  19. Copper-spent activated carbon as a heterogeneous peroxydisulfate catalyst for the degradation of Acid Orange 7 in an electrochemical reactor.

    Science.gov (United States)

    Li, Jing; Lin, Heng; Yang, Lin; Zhang, Hui

    2016-01-01

    The exhausted activated carbon generated from the adsorption of heavy metal wastewater needs further treatment/disposal. In this study, a new application of copper-spent activated carbon (Cu-AC) was proposed. Cu-AC was used to activate peroxydisulfate (PDS) for the decolorization of Acid Orange 7 (AO7) and electrical current was introduced to enhance the process. The decolorization followed a pseudo-first-order kinetic pattern well (R(2) > 0.95). 92.4% of color removal at 60 min and 38.3% of total organic carbon removal at 180 min were achieved when initial pH value was 9.0, current density was 16 mA/cm(2), PDS concentration was 5 mM and Cu-AC dosage was 0.25 g/L. The radical scavengers including methanol, tert-butanol and phenol, as well as electron paramagnetic resonance test, were employed to investigate the oxidizing species responsible for AO7 decolorization. The stability of Cu-AC was confirmed by three recycle experiments.

  20. Tuning the spectral, morphological and photophysical properties of sonochemically synthesized poly(carbazole) using acid Orange, fluorescein and rhodamine 6G

    Science.gov (United States)

    Riaz, Ufana; Ashraf, S. M.; Fatima, Talat; Jadoun, Sapana

    2017-02-01

    The lifetimes and quantum yields of organic dyes are widely investigated due to their potential application in organic light emitting diodes (OLEDs). With a view to explore the possibility of enhancing the fluorescent properties of organic conjugated polymers such as polycarbazole, the present preliminary study reports for the first time, dye modification of polycarbazole using as acid orange (AO), fluorescein (Fluo) and Rhodamine 6G (R6G) for improving its fluorescence properties. The modification of PCz via doping was confirmed by FTIR, UV-visible, XRD and TEM analyses. The fluorescence studies and confocal microscopy were carried out both in solution and solid states to investigate the behavior of the dye modified PCz. Doping was found to be governed by the chemical structure of the dye. PCz-AO revealed intense doping which was confirmed by FTIR and UV-visible studies. PCz-Fluo and PCz-R6G exhibited the highest quantum yield and fluorescence emission in the solid state. Hence, by tailoring the structure of these conjugated polymers, stable fluorescence emitting materials can be designed for their potential application in OLEDs.

  1. Role of pH in the Aqueous Phase Reactivity of Zerovalent Iron Nanoparticles with Acid Orange 7, a Model Molecule of Azo Dyes

    Directory of Open Access Journals (Sweden)

    F. S. Freyria

    2017-01-01

    Full Text Available The effect of both pH and surface oxidation of nanoparticles is studied on the interaction between a commercial slurry of Nanoscale Zerovalent Iron (NZVI and the azo dye Acid Orange 7 (AO7. NZVI is a reducing agent used for the degradation of several pollutants, including azo dyes: during pollutant degradation, it undergoes progressive oxidation and dissolution. Though it is generally acknowledged that NZVI consists of core-shell nanoparticles, where the core of metallic iron is covered by FexOy shell, it still remains a poorly defined system. In this work, the solid fraction recovered by filtration and drying was characterized by means of XRD diffraction with Rietveld refinement, N2 isotherms at 77 K, FE-SEM and TEM observation, EDX analysis, and IR spectroscopy. Powders were obtained from both the parent slurry and the same slurry pretreated with HCl in order to remove FexOy shell, finally reactivating the nanoparticles. The aforementioned physicochemical characterization allowed figuring out some correlations between the properties of the studied nanomaterial and the processes occurring when it is in contact with AO7 in aqueous phase. The type of interaction occurring within the NZVI/AO7 system (adsorption and type of redox reactions strongly depends not only on the pH of the starting solution, but also on the surface oxidation of the nanoparticles.

  2. Eco-friendly chitosan production by Syncephalastrum racemosum and application to the removal of acid orange 7 (AO7) from wastewaters.

    Science.gov (United States)

    Batista, Anabelle C L; Silva, Marta C Freitas; Batista, Jefferson B; Nascimento, Aline Elesbão; Campos-Takaki, Galba M

    2013-07-01

    Due to the existence of new methodologies that have reduced the production costs of microbiological chitosan, this paper puts forward the use of agro-industrial residues in order to produce microbiological chitosan and to apply chitosan as an innovative resource for removing acid orange 7 (AO7) from wastewaters. The best culture conditions were selected by a full 24 factorial design, and the removal of the dye was optimized by a 23 central composite rotational design. The results showed that corn steep liquor (CSL) is an agro-industrial residue that can be advantageously used to produce microbiological chitosan with yields up to 7.8 g/kg of substrate. FT-IR spectra of the product showed typical peak distributions like those of standard chitosan which confirmed the extracted product was chitosan-like. The efficiency of removing low concentrations of AO7 by using microbiological chitosan in distilled water (up to 89.96%) and tap water (up to 80.60%) was significantly higher than the efficiency of the control (chitosan obtained from crustaceans), suggesting that this biopolymer is a better economic alternative for discoloring wastewater where a low concentration of the dye is considered toxic. The high percentage recovery of AO7 from the microbiological chitosan particles used favors this biopolymer as a possible bleaching agent which may be reusable.

  3. Eco-Friendly Chitosan Production by Syncephalastrum racemosum and Application to the Removal of Acid Orange 7 (AO7 from Wastewaters

    Directory of Open Access Journals (Sweden)

    Aline Elesbão Nascimento

    2013-07-01

    Full Text Available Due to the existence of new methodologies that have reduced the production costs of microbiological chitosan, this paper puts forward the use of agro-industrial residues in order to produce microbiological chitosan and to apply chitosan as an innovative resource for removing acid orange 7 (AO7 from wastewaters. The best culture conditions were selected by a full 24 factorial design, and the removal of the dye was optimized by a 23 central composite rotational design. The results showed that corn steep liquor (CSL is an agro-industrial residue that can be advantageously used to produce microbiological chitosan with yields up to 7.8 g/kg of substrate. FT-IR spectra of the product showed typical peak distributions like those of standard chitosan which confirmed the extracted product was chitosan-like. The efficiency of removing low concentrations of AO7 by using microbiological chitosan in distilled water (up to 89.96% and tap water (up to 80.60% was significantly higher than the efficiency of the control (chitosan obtained from crustaceans, suggesting that this biopolymer is a better economic alternative for discoloring wastewater where a low concentration of the dye is considered toxic. The high percentage recovery of AO7 from the microbiological chitosan particles used favors this biopolymer as a possible bleaching agent which may be reusable.

  4. Fabrication of graphene–TiO$_2$ nanocomposite with improved photocatalytic degradation for acid orange 7 dye under solar light irradiation

    Indian Academy of Sciences (India)

    VENKATA RAMANA POSA; VISWADEVARAYALU ANNAVARAM; ADINARAYANA REDDY SOMALA

    2016-06-01

    In this study, photodegradation of the non-biodegradable azo dye acid orange 7 (AO7) was selected as modal target in aqueous solution using graphene–TiO$_2$ (GR–TiO$_2$) hybrid nanocomposite, was well investigatedand elucidated. The crystal phase, special surface area, microscopic analysis of the GR–TiO$_2$ and also, chemical state of the photocatalysts were studied by powdered X-ray diffraction (PXRD), Raman spectrum, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high resolution scanning electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Brunauere Emmette Teller (BET) method andphotoluminescence spectroscopy (PL). During photocatalysis, the GR–TiO$_2$ nanocomposite improved photocatalytic performance compared with that of pure TiO$_2$ towards AO7 organic azo-dye degradation. The reusability test ofphotocatalytic activity was also examined. A conceivable reaction mechanism was suggested and nattered on the basis of tentative effects. Therefore, the GR–TiO$_2$ nanomaterial can be widely used as a photocatalyst for treatingthe organic dye contaminant in the field of environmental protection.

  5. Fabrication of granular activated carbons derived from spent coffee grounds by entrapment in calcium alginate beads for adsorption of acid orange 7 and methylene blue.

    Science.gov (United States)

    Jung, Kyung-Won; Choi, Brian Hyun; Hwang, Min-Jin; Jeong, Tae-Un; Ahn, Kyu-Hong

    2016-11-01

    Biomass-based granular activated carbon was successfully prepared by entrapping activated carbon powder derived from spent coffee grounds into calcium-alginate beads (SCG-GAC) for the removal of acid orange 7 (AO7) and methylene blue (MB) from aqueous media. The dye adsorption process is highly pH-dependent and essentially independent of ionic effects. The adsorption kinetics was satisfactorily described by the pore diffusion model, which revealed that pore diffusion was the rate-limiting step during the adsorption process. The equilibrium isotherm and isosteric heat of adsorption indicate that SCG-GAC possesses an energetically heterogeneous surface and operates via endothermic process in nature. The maximum adsorption capacities of SCG-GAC for AO7 (pH 3.0) and MB (pH 11.0) adsorption were found to be 665.9 and 986.8mg/g at 30°C, respectively. Lastly, regeneration tests further confirmed that SCG-GAC has promising potential in its reusability, showing removal efficiency of more than 80% even after seven consecutive cycles.

  6. [Molluscacide activity of a mixture of 6-n-alkyl salicylic acids (anacardic acid) and 2 of its complexes with copper (II) and lead (II)].

    Science.gov (United States)

    Mendes, N M; de Oliveira, A B; Guimarães, J E; Pereira, J P; Katz, N

    1990-01-01

    The molluscicide activity of hexanic extract from Anacardium occidentale L. (cashew) nut shell, of copper (II) complex, of lead (II) complex and anacardic acid has been compared in the laboratory in an attempt to obtain better stability than anacardic acid. This was obtained from the hexanic extract of the cashew nut shell by precipitation with lead (II) hydroxide or cupric sulfate plus sodium hydroxide or (II) cupric hydroxide followed by treatment of lead (II) complex with a diluted solution of sulfuric acid. Ten products of the mixture obtained were tested on adults snails of Biomphalaria glabrata at 1 to 10 ppm. The most active products were copper (II) complex, obtained by cupric sulfate plus sodium hydroxide, and anacardic acid (sodium hydroxide) which presented activity at 4 ppm. The anacardic acid's lead content was above the limits accepted by the United States standards.

  7. Dark ambient degradation of Bisphenol A and Acid Orange 8 as organic pollutants by perovskite SrFeO{sub 3−δ} metal oxide

    Energy Technology Data Exchange (ETDEWEB)

    Leiw, Ming Yian, E-mail: LEIW0003@e.ntu.edu.sg [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); GlobalFoundries Singapore Pte. Ltd., 60 Woodlands Industrial Park D Street 2, Singapore 738406 (Singapore); Guai, Guan Hong [GlobalFoundries Singapore Pte. Ltd., 60 Woodlands Industrial Park D Street 2, Singapore 738406 (Singapore); School of Chemical and Biomedical Engineering and Center for Advanced Bionanosystems, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457 (Singapore); Wang, Xiaoping [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Tse, Man Siu [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Ng, Chee Mang [GlobalFoundries Singapore Pte. Ltd., 60 Woodlands Industrial Park D Street 2, Singapore 738406 (Singapore); Tan, Ooi Kiang [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2013-09-15

    Highlights: • Perovskite SFO prepared by high temperature and high-energy ball milling process. • SFO metal oxide shows good efficiency in degrading and mineralizing BPA. • Rapid decoloration of AO8 was achieved in the presence of SFO metal oxide. • O{sub 2}·{sup −} is the predominant ROS for dark oxidative degradation of BPA and AO8. -- Abstract: Current advanced oxidation processes (AOPs) are chemically and energetically intensive processes, which are undesirable for cost-effective and large-scale system water treatment and wastewater recycling. This study explored the Strontium Ferrite (SFO) metal oxide on the degradation of highly concentrated organic pollutants under dark ambient condition without any external stimulants. The SFO particles with single perovskite structure were successfully synthesized with a combined high temperature and high-energy ball milling process. An endocrine disruptor, Bisphenol A (BPA) and an azo dye, Acid Orange 8 (AO8) were used as probe organic pollutants. BPA was completely degraded with 83% of mineralization in 24 h while rapid decoloration of AO8 was achieved in 60 min and complete breakdown into primary intermediates and aliphatic acids occurred in 24 h under the treatment of dispersed SFO metal oxide in water. Such efficient degradation could be attributed to the enhanced adsorption of these anionic pollutants on positively charged ball-milled SFO metal oxide surface, resulted in higher degradation activity. Preliminary degradation mechanisms of BPA and AO8 under the action of SFO metal oxide were proposed. These results showed that the SFO metal oxide could be an efficient alternative material as novel advanced oxidation technology for low cost water treatment.

  8. Sonophotocatalytic degradation of dye C.I. Acid Orange 7 by TiO2 and Ag nanoparticles immobilized on corona pretreated polypropylene non-woven fabric.

    Science.gov (United States)

    Marković, Darka; Šaponjić, Zoran; Radoičić, Marija; Radetić, Tamara; Vodnik, Vesna; Potkonjak, Branislav; Radetić, Maja

    2015-05-01

    This study discusses the possibility of using corona pre-treated polypropylene (PP) non-woven fabric as a support for immobilization of colloidal TiO2 and Ag nanoparticles in order to remove dye C.I. Acid Orange 7 from aqueous solution. Dye removal efficiency by sonocatalysis, photocatalysis and sonophotocatalysis was evaluated on corona pre-treated fabric loaded with TiO2 nanoparticles, corona pre-treated fabric double loaded with TiO2 nanoparticles and corona pre-treated fabrics loaded with TiO2 nanoparticles before and after deposition of Ag nanoparticles. In addition, the stability of PP non-woven fabric during these processes was investigated. The substrates were characterized by SEM, EDX and AAS analyses. The change of the dye concentration was evaluated by UV-VIS spectrophotometry. Unlike sonocatalysis and photocatalysis, complete dye removal from both solution and non-woven fabric was obtained already after 240-270 min of sonophotocatalysis. Corona pre-treated PP non-woven fabric loaded with Ag nanoparticles prior to deposition of TiO2 nanoparticles provided excellent degradation efficiency and superior reusability. Sonophotocatalytic degradation of dye in the presence of all investigated samples was the most prominent in acidic conditions. Although this nanocomposite system ensured fast discoloration of dye solution, TOC values of water measured after sonophotocatalysis were not satisfactory because of PP degradation. Therefore, it is suggested to include TOC evaluation in each case study where different supports for TiO2 nanoparticles are used since these nanoparticles may guarantee the dye removal from solution but the stability of support could be problematic causing even more serious environmental impact.

  9. Vitamin C Content of Commercial Orange Juices

    Science.gov (United States)

    Haddad, Paul

    1977-01-01

    Describes an experiment designed to confirm that newly purchased commercial orange juice contains sufficient ascorbic acid to meet government standards, and to establish the rate of aerial oxidation of this ascorbic acid when the juice is stored in a refrigerator. (MLH)

  10. Oxygenation of Organoboronic Acids by a Nonheme Iron(II) Complex: Mimicking Boronic Acid Monooxygenase Activity.

    Science.gov (United States)

    Chatterjee, Sayanti; Paine, Tapan Kanti

    2015-10-19

    Phenolic compounds are important intermediates in the bacterial biodegradation of aromatic compounds in the soil. An Arthrobacter sp. strain has been shown to exhibit boronic acid monooxygenase activity through the conversion of different substituted phenylboronic acids to the corresponding phenols using dioxygen. While a number of methods have been reported to cleave the C-B bonds of organoboronic acids, there is no report on biomimetic iron complex exhibiting this activity using dioxygen as the oxidant. In that direction, we have investigated the reactivity of a nucleophilic iron-oxygen oxidant, generated upon oxidative decarboxylation of an iron(II)-benzilate complex [(Tp(Ph2))Fe(II)(benzilate)] (Tp(Ph2) = hydrotris(3,5-diphenyl-pyrazol-1-yl)borate), toward organoboronic acids. The oxidant converts different aryl/alkylboronic acids to the corresponding oxygenated products with the incorporation of one oxygen atom from dioxygen. This method represents an efficient protocol for the oxygenation of boronic acids with dioxygen as the terminal oxidant.

  11. ORANGE: RANGE OF BENEFITS

    Directory of Open Access Journals (Sweden)

    Parle Milind

    2012-07-01

    Full Text Available No wonder that oranges are one of the most popular fruits in the world. Orange (citrus sinensis is well known for its nutritional and medicinal properties throughout the world. From times immemorial, whole Orange plant including ripe and unripe fruits, juice, orange peels, leaves and flowers are used as a traditional medicine. Citrus sinensis belongs to the family Rutaceae. The fruit is a fleshy, indehiscent, berry that ranges widely in size from 4 cm to 12 cm. The major medicinal properties of orange include anti-bacterial, anti-fungal, anti- diabetic, cardio- protective, anti-cancer, anti-arthritic, anti-inflammatory, anti-oxidant, anti-Tubercular, anti-asthmatic and anti-hypertensive. Phytochemically, whole plant contains limonene, citral, neohesperidin, naringin, rutin, rhamnose, eriocitrin, and vitamin-C. In the present review article, a humble attempt is made to compile all the strange facts available about this tasty fruit.

  12. Recovery of aroma compounds from orange essential oil

    Directory of Open Access Journals (Sweden)

    Haypek E.

    2000-01-01

    Full Text Available The objective of this work was to study the recovery of aroma compounds present in the orange essential oil using experimental data from CUTRALE (a Brazilian Industry of Concentrated Orange Juice. The intention was to reproduce the industrial unit and afterwards to optimize the recovery of aroma compounds from orange essential oil by liquid-liquid extraction. The orange oil deterpenation was simulated using the commercial software PRO/II 4.0 version 1.0. The UNIFAC model was chosen for the calculation of the activity coefficients.

  13. Aerobic decolorization and degradation of Acid Orange G (AOG) by suspended growing cells and immobilized cells of a yeast strain Candida tropicalis TL-F1.

    Science.gov (United States)

    Tan, Liang; Li, Hua; Ning, Shuxiang; Hao, Jia

    2014-10-01

    In this study, aerobic decolorization and degradation of azo dye Acid Orange G (AOG) by both suspended growing cells and immobilized cells of a yeast strain Candida tropicalis TL-F1 were studied. The effects of different parameters on decolorization of AOG by both growing suspended and immobilized strain TL-F1 were investigated. Furthermore, a possible decolorization mechanism of AOG was proposed through analyzing metabolic intermediates using UV-vis and high-performance liquid chromatography-mass spectrometry (HPLC-MS) methods. Strain TL-F1 could decolorize AOG in both liquid and solid mediums through degradation. The optimal conditions for decolorization with suspended growing cells of strain TL-F1 were as follows: 6-10 g/L sucrose, 5-7 g/L urea, ≥6 % (v/v) inoculation size, ≥160 rpm, 35-40 °C, and pH 5.0-6.0; and those for immobilized cells, the conditions were as follows: 4-6 g/L glucose, 0.2-0.4 g/L urea, 6-10 g/L (wet cell pellets) inoculation size, ≥160 rpm, 35-40 °C, and pH 5.0-7.0. Results of UV-vis scanning spectra suggested that AOG was decolorized through biodegradation, and the possible pathway was proposed through the results of HPLC-MS analysis and related literature. This is a systematic research on aerobic decolorization and degradation of AOG by both suspended and immobilized cells of a C. tropicalis strain.

  14. Reagents for selective extraction of nickel(II), cobalt(II) and copper(II) from highly acidic sulfate feeds containing iron

    OpenAIRE

    Roebuck, James William

    2015-01-01

    This thesis focuses on development of new regents which are suitable for recovering nickel, cobalt and copper from laterite leach solutions, specifically focusing on reagent requirements for novel base metal flowsheets developed by Anglo American. The work aims to design reagents which can extract nickel(II), cobalt(II) and copper(II) from a highly acidic aqueous sulfate solutions whilst showing selectivity over iron(II) and iron(III). Chapter 1 reviews current extractive metallur...

  15. Free proline content in orange juice by amono acid ananlyzer%利用氨基酸分析仪对橙汁中脯氨酸定量研究

    Institute of Scientific and Technical Information of China (English)

    葛冬梅; 王震

    2012-01-01

    利用氨基酸分析仪对橙汁饮料中的游离脯氨酸进行测定,结果表明,橙汁饮料中含有一定量的脯氨酸,其含量差异较大,含量范围在0~919mg/L之间。分析果汁含量和脯氨酸含量之间的关系,结果表明,其含量的大小不能作为橙汁饮料中天然果汁含量多少的判定依据,要综合考虑其他的检测因子才能判定是否掺假。%The content of free proline(Pro) in orange juice was tested by using Hitachi type L-8900 amino acid analysis analyzer.The results showed that the difference of Pro contents in different samples were quite large with ranges 0~919 mg/L.Analysis the relationship between the content of juice and Pro,showed that there is no relevance.So we cann’t decide the content of orange juice basis of the content of Pro,the other factor should be considered in order to decision an adulterated orange juice.

  16. Abiotic reduction of nitroaromatic compounds by Fe(II) associated with iron oxides and humic acid.

    Science.gov (United States)

    Luan, Fubo; Xie, Li; Li, Jun; Zhou, Qi

    2013-05-01

    Experiments were conducted to examine the reduction of nitroaromatic compounds (NACs) by Fe(II) associated with iron oxides (goethite, hematite and magnetite) and humic acid. The reduction rate of nitrobenzene decreased in the order of Fe(II) associated with magnetite>Fe(II) associated with goethite>Fe(II) associated with hematite. We proposed a four-step model (adsorption, electron transfer to conduction band, electron transfer to nitrobenzene and electron transfer to crystal lattice) for nitrobenzene reduction by Fe(II) associated with iron oxides. Fe(II)-humic acid complexes did not present reduction capability of nitrobenzene. Furthermore, Humic acid significantly inhibited nitrobenzene reduction by Fe(II) associated with iron oxides. The inhibitory effect of humic acid toward the reduction of nitrobenzene decreased in the order of magnetite>goethite>hematite. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Micellar effect on metal-ligand complexes of Co(II, Ni(II, Cu(II and Zn(II with citric acid

    Directory of Open Access Journals (Sweden)

    Nageswara Rao Gollapalli

    2009-12-01

    Full Text Available Chemical speciation of citric acid complexes of Co(II, Ni(II, Cu(II and Zn(II was investigated pH-metrically in 0.0-2.5% anionic, cationic and neutral micellar media. The primary alkalimetric data were pruned with SCPHD program. The existence of different binary species was established from modeling studies using the computer program MINIQUAD75. Alkalimetric titrations were carried out in different relative concentrations (M:L:X = 1:2:5, 1:3:5, 1:5:3 of metal (M to citric acid. The selection of best chemical models was based on statistical parameters and residual analysis. The species detected were MLH, ML2, ML2H and ML2H2. The trend in variation of stability constants with change in mole fraction of the medium is explained on the basis of electrostatic and non-electrostatic forces. Distributions of the species with pH at different compositions of micellar media are also presented.

  18. Copper (II) diamino acid complexes: Quantum chemical computations regarding diastereomeric effects on the energy of complexation

    NARCIS (Netherlands)

    Zuilhof, H.; Morokuma, K.

    2003-01-01

    Quantum chemical calculations were used to rationalize the observed enantiodifferentiation in the complexation of alpha-amino acids to chiral Cu(II) complexes. Apart from Cu(II)-pi interactions and steric repulsions between the anchoring cholesteryl-Glu moiety and an aromatic amino acid R group, hyd

  19. Utilization of a Biodegradable Mulch Sheet Produced from Poly(Lactic Acid/Ecoflex®/Modified Starch in Mandarin Orange Groves

    Directory of Open Access Journals (Sweden)

    Yasukatsu Maeda

    2009-08-01

    Full Text Available We have developed a mulch sheet made by inflation molding of PLA, Ecoflex® and modified starch, which all have different biodegradabilities. A field test of use as an agricultural mulch sheet for mandarin oranges was carried out over two years. The mechanical properties of the mulch sheet were weakened with time during the field test, but the quality of the mandarin oranges increased, a result of the controlled degradation of the sheet. The most degradable modified starch degraded first, allowing control of the moisture on the soil. Accelerator mass spectroscopy was used for evaluation of the biomass carbon ratio. The biomass carbon ratio decreased by degradation of the biobased materials, PLA and modified starch in the mulch sheet.

  20. A Copper-Assisted Palladium(II)-catalyzed Direct Arylation of Cyclic Enaminones with Arylboronic Acids

    OpenAIRE

    Kim, Yong Wook; Niphakis, Micah J.; Georg, Gunda I.

    2012-01-01

    Described herein is a palladium(II)-catalyzed direct arylation of cyclic enaminones with arylboronic acids. The versatility of this method is that both electron-rich and electron-poor boronic acids can be coupled in high yields. A mixture of two Cu(II) additives was crucial for efficient cross-coupling. The role of each Cu(II) reagent appears to be distinct and complementary serving to assist catalyst reoxidation and transmetallation through a putative arylcopper intermediate.

  1. A comparative study of natural, formaldehyde-treated and copolymer-grafted orange peel for Pb(II) adsorption under batch and continuous mode.

    Science.gov (United States)

    Lugo-Lugo, Violeta; Hernández-López, Susana; Barrera-Díaz, Carlos; Ureña-Núñez, Fernando; Bilyeu, Bryan

    2009-01-30

    Natural, formaldehyde-treated and copolymer-grafted orange peels were evaluated as adsorbents to remove lead ions from aqueous solutions. The optimum pH for lead adsorption was found to be pH 5. The adsorption process was fast, reaching 99% of sorbent capacity in 10 min for the natural and treated biomasses and 20 min for the grafted material. The treated biomass showed the highest sorption rate and capacity in the batch experiments, with the results fitting well to a pseudo-first order rate equation. In the continuous test with the treated biomass, the capacity at complete exhaustion was 46.61 mg g(-1) for an initial concentration of 150 mg L(-1). Scanning electronic microscopy and energy dispersive X-ray spectroscopy indicated that the materials had a rough surface, and that the adsorption of the metal took place on the surface. Fourier transform infrared spectroscopy revealed that the functional groups responsible for metallic biosorption were the -OH, -COOH and -NH(2) groups on the surface. Finally, the thermogravimetric analysis indicates that a mass reduction of 80% can be achieved at 600 degrees C.

  2. A comparative study of natural, formaldehyde-treated and copolymer-grafted orange peel for Pb(II) adsorption under batch and continuous mode

    Energy Technology Data Exchange (ETDEWEB)

    Lugo-Lugo, Violeta; Hernandez-Lopez, Susana [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon interseccion Paseo Tollocan S/N, C.P. 50120, Toluca, Estado de Mexico (Mexico); Barrera-Diaz, Carlos [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon interseccion Paseo Tollocan S/N, C.P. 50120, Toluca, Estado de Mexico (Mexico)], E-mail: cbarrera@uaemex.mx; Urena-Nunez, Fernando [Instituto Nacional de Investigaciones Nucleares, A.P.18-1027, Col. Escandon, Delegacion Miguel Hidalgo, C.P. 11801, Mexico, D.F. (Mexico); Bilyeu, Bryan [Xavier University of Louisiana, Department of Chemistry, 1 Drexel Drive, New Orleans, LA 70125 (United States)

    2009-01-30

    Natural, formaldehyde-treated and copolymer-grafted orange peels were evaluated as adsorbents to remove lead ions from aqueous solutions. The optimum pH for lead adsorption was found to be pH 5. The adsorption process was fast, reaching 99% of sorbent capacity in 10 min for the natural and treated biomasses and 20 min for the grafted material. The treated biomass showed the highest sorption rate and capacity in the batch experiments, with the results fitting well to a pseudo-first order rate equation. In the continuous test with the treated biomass, the capacity at complete exhaustion was 46.61 mg g{sup -1} for an initial concentration of 150 mg L{sup -1}. Scanning electronic microscopy and energy dispersive X-ray spectroscopy indicated that the materials had a rough surface, and that the adsorption of the metal took place on the surface. Fourier transform infrared spectroscopy revealed that the functional groups responsible for metallic biosorption were the -OH, -COOH and -NH{sub 2} groups on the surface. Finally, the thermogravimetric analysis indicates that a mass reduction of 80% can be achieved at 600 deg. C.

  3. Physicochemical Characteristics of Orange Juice Samples From Seven Cultivars

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Some physicochemical parameters of orange juice from seven orange varieties (Pineapple orange, Hamlin, Trovita, Jincheng,1232 Tangor, Olinda Valencia, and Delta Valencia) were analyzed, special attention was paid to the level of sugars, organic acids, free amino acids, mineral composition, and color parameters. The results showed that total soluble solids (TSS),TSS/titratable acidity (TA) ratios, sugars, and organic acids were kept within a proper range for juice processing except that Jincheng had lower TSS than the others. Sucrose was the most dominant sugar in the orange cultivars, followed by fructose and glucose, while citric acid was the principal organic acid. Serine and proline were the principal amino acids.Potassium was the most abundant mineral in all of the juice samples, followed by magnesium and calcium. The sodium content of most varieties was under 10 mg kg-1. Though all of the samples had orange colour, Olinda Valencia and Delta Valencia had deeper red colour than the others. Statistically significant differences (P < 0.05) were found between the samples in most of the characteristics. The results provided important information on the physicochemical characteristics of the varieties and on how to make the best use of orange cultivars for different purposes, which is of significance for both technological research and processing practice.

  4. Heavy metal/polyacid interaction. An electrochemical study of the binding of Cd(II), Pb(II) and Zn(II) to polycarboxylic and humic acids

    NARCIS (Netherlands)

    Cleven, R.F.M.J.

    1984-01-01

    Polyelectrolyte effects in the interaction of heavy metal ions with model polycarboxylic acids have been described, in order to establish the relevance of these effects in the interaction of heavy metal ions with naturally occurring humic and fulvic acids. The model systems consisted of Cd(II), Pb(I

  5. .Investigation the  Zero-Valent Iron (ZVI Performance in the Presence of UV light and Hydrogen Peroxide on Removal of Azo Dyes Acid Orange 7 and Reactive Black 5 from Aquatic Solutions

    Directory of Open Access Journals (Sweden)

    Mansur Zarrabi

    2013-02-01

    Full Text Available Background and Objectives: Colored wastewaters are known as one of the most important sources of environmental pollutants. Having toxic chemicals and aesthetic problems has made treatment of these wastewaters very crucial. So far a number of methods such as electrochemical treatment, coagulation and flocculation, and adsorption have been used for treatment of textile industries wastewater. Hence,  the efficiency of zero-valent iron powder in the presence of UV light and hydrogen peroxide to remove Acid Orange 7 and Reactive Black 5 from the synthetic solutions was investigated.Materials and Methods: Conducting all experiments in a batch reactor, we examined different parameters including initial concentration of the color (25, 50, 75 mg/L, contact time (30,  60, 120 min, pH (3, 7, 11, the amount of iron powder (0.6, 1.3,  2  g/l, and hydrogen peroxide concentration (10, 15, 20  ml/l.Result: The results showed that dye removal efficiency was increased by increasing contact time, the amount of iron powder and hydrogen peroxide concentration. On the other hand, with the increasing pH and initial concentration of dye, removal efficiency decreased in both AO7and RB5 dyes.Conclusion: We found that the integrated ZVI/UV/H2O2 method has  high efficiency in removing azo dyes Acid Orange 7 and Reactive Black 5.

  6. Transformation of Unsaturated Fatty Acids/Esters to Corresponding Keto Fatty Acids/Esters by Aerobic Oxidation with Pd(II)/Lewis Acid Catalyst.

    Science.gov (United States)

    Senan, Ahmed M; Zhang, Sicheng; Zeng, Miao; Chen, Zhuqi; Yin, Guochuan

    2017-08-16

    Utilization of renewable biomass to partly replace the fossil resources in industrial applications has attracted attention due to the limited fossil feedstock with the increased environmental concerns. This work introduced a modified Wacker-type oxidation for transformation of unsaturated fatty acids/esters to the corresponding keto fatty acids/esters, in which Cu(2+) cation was replaced with common nonredox metal ions, that is, a novel Pd(II)/Lewis acid (LA) catalyst. It was found that adding nonredox metal ions can effectively promote Pd(II)-catalyzed oxidation of unsaturated fatty acids/esters to the corresponding keto fatty acids/esters, even much better than Cu(2+), and the promotional effect is highly dependent on the Lewis acidity of added nonredox metal ions. The improved catalytic efficiency is attributed to the formation of heterobimetallic Pd(II)/LA species, and the oxidation mechanism of this Pd(II)/LA catalyst is also briefly discussed.

  7. Type II fatty acid synthesis is essential only for malaria parasite late liver stage development

    OpenAIRE

    Vaughan, Ashley M.; O'Neill, Matthew T.; Tarun, Alice S.; Camargo, Nelly; Phuong, Thuan M; Aly, Ahmed S I; Cowman, Alan F.; Kappe, Stefan H. I.

    2008-01-01

    Intracellular malaria parasites require lipids for growth and replication. They possess a prokaryotic type II fatty acid synthesis (FAS II) pathway that localizes to the apicoplast plastid organelle and is assumed to be necessary for pathogenic blood stage replication. However, the importance of FAS II throughout the complex parasite life cycle remains unknown. We show in a rodent malaria model that FAS II enzymes localize to the sporozoite and liver stage apicoplast. Targeted deletion of Fab...

  8. Spectroscopic (FT-IR, FT-Raman, 1H, 13C NMR, UV/VIS), thermogravimetric and antimicrobial studies of Ca(II), Mn(II), Cu(II), Zn(II) and Cd(II) complexes of ferulic acid

    Science.gov (United States)

    Kalinowska, M.; Piekut, J.; Bruss, A.; Follet, C.; Sienkiewicz-Gromiuk, J.; Świsłocka, R.; Rzączyńska, Z.; Lewandowski, W.

    2014-03-01

    The molecular structure of Mn(II), Cu(II), Zn(II), Cd(II) and Ca(II) ferulates (4-hydroxy-3-methoxycinnamates) was studied. The selected metal ferulates were synthesized. Their composition was established by means of elementary and thermogravimetric analysis. The following spectroscopic methods were used: infrared (FT-IR), Raman (FT-Raman), nuclear magnetic resonance (13C, 1H NMR) and ultraviolet-visible (UV/VIS). On the basis of obtained results the electronic charge distribution in studied metal complexes in comparison with ferulic acid molecule was discussed. The microbiological study of ferulic acid and ferulates toward Escherichia coli, Bacillus subtilis, Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus and Proteus vulgaris was done.

  9. Operation Orange Street Resurfacing 2016

    Data.gov (United States)

    City of Jackson, Mississippi — Track Operation Orange Cone projects for 2016. “Operation Orange Cone” is an initiative launched in 2015 as part of the Yarber Administration’s push to address the...

  10. Iminodiacetic acid functionalized cation exchange resin for adsorptive removal of Cr(VI), Cd(II), Ni(II) and Pb(II) from their aqueous solutions.

    Science.gov (United States)

    Misra, R K; Jain, S K; Khatri, P K

    2011-01-30

    Iminodiacetic acid functionality has been introduced on styrene-divinyl benzene co-polymeric beads and characterized by FT-IR in order to develop weak acid based cation exchange resin. This resin was evaluated for the removal of different heavy metal ions namely Cd(II), Cr(VI), Ni(II) and Pb(II) from their aqueous solutions. The results showed greater affinity of resin towards Cr(VI) for which 99.7% removal achieved in optimal conditions following the order Ni(II)>Pb(II)>Cd(II) with 65%, 59% and 28% removal. Experiments were also directed towards kinetic studies of adsorption and found to follow first order reversible kinetic model with the overall rate constants 0.3250, 0.2393, 0.4290 and 0.2968 for Cr(VI), Ni(II), Pb(II) and Cd(II) removal respectively. Detailed studies of Cr(VI) removal has been carried out to see the effect of pH, resin dose and metal ion concentration on adsorption and concluded that complexation enhanced the chromium removal efficacy of resin drastically, which is strongly pH dependent. The findings were also supported by the comparison of FT-IR spectra of neat resin with the chromium-adsorbed resin.

  11. Enantioseparation of Amino Acids by Micelle-Enhanced Ultrafiltration : Experimental and Theoretical Studies of Copper(II) Amino Acid Interactions

    NARCIS (Netherlands)

    Bruin, de T.J.M.

    2000-01-01

    A micelle-enhanced ultrafiltration system, which can potentially be used for large scale separations, has been used to investigate the resolution of amino acid enantiomers. For this purpose amino acid derivatives were synthesized, which in combination with copper(II) ions were used as chiral selecto

  12. 甜橙键合态芳香组分的酶(酸)解解离方法研究%Study on the Separation Method of Bound Flavour Component from Sweet Orange by Enzyme(Acid)

    Institute of Scientific and Technical Information of China (English)

    孙爱东; 葛毅强; 阎红; 倪元颖; 蔡同一

    2001-01-01

    In this paper, the separation of free and bound flavour component from orange juice by Amberlite XAD-2 absorption and methanol elution is processed, followed by simultaneous enzyme catalysis extraction using glucosidase and hydrochloric acid to release the potential flavour component from orange juice. The suitable resolve method is decided by the comparison of flavour components of different reaction fashions.%以甜橙为研究对象,通过采用Amberlite XAD-2树脂吸附溶剂解吸法,对橙汁的游离态与键合态芳香组分进行分离,然后酶(酸)解键合态组分,释放橙汁中的潜在芳香组分。通过对酶(酸)解反应方式释放的芳香组分的比较,确定适宜的解离方法。

  13. Delaying senescence of 'Ruby Red' grapefruit and 'Valencia' oranges by gibberellic acid applications Uso de ácido giberélico para retrasar la senescencia de toronja'Ruby Red' y naranja 'Valencia'

    Directory of Open Access Journals (Sweden)

    Martín Aluja

    2011-02-01

    Full Text Available The demonstrate the effectiveness of gibberellic acid (GA3 in delaying fruit senescence in 'Ruby Red' grapefruit and 'Valencia' oranges under sub-optimal orchard management conditions in tropical Veracruz, Mexico. For grapefruit, one or two applications of three different GA3 doses (15, 20 and 40 mg L-1 with or without surfactant (Silwet® L77 at 0.035, 0.05 or 0.1%, were tested. For oranges, one or two applications of three different GA3 doses (10, 15 and 20 mg L-1 with or without surfactant at 0.05%, were tested. Pre-color break application of GA3, at 10 mg L-1 and 15 mg L-1 with surfactant (0.05%, was sufficient to sustain peel firmness and delay colour development in oranges and grapefruit, respectively. GA3 treatments with surfactant caused increased leaf drop in both citrus cultivars, although this was only noticed in trees treated with the highest surfactant dosages and mainly involved photosynthetically inactive leaves. One application of GA3 at 15 mg L-1 with surfactant (0.05% significantly increased orange and grapefruit weights, resulting in yield increases of ca. 1.7 t ha-1 for oranges and 1.87 t ha-1 for grapefruit. A significant decrease in orange drop during the late harvest season in GA3 treated trees, resulted in a harvest period that could be extended by up to six weeks. The market value of fruit harvested late in the season is up to eight times the value of fruit harvested when the market is saturated.Los datos demuestran la efectividad del ácido giberélico (AG3 para retrasar la senescencia del fruto en toronja 'Ruby Red' y naranja 'Valencia', aún bajo condiciones sub-óptimas de manejo en la región tropical de Veracruz, México. En toronja, experimentamos con una o dos aplicaciones de tres dosis de AG3 (15, 20 y 40 mg L-1 con o sin surfactante (Silwet® L77 a 0.035, 0.05 ó 0.1%. En el caso de la naranja, experimentamos con una o dos aplicaciones de tres dosis de AG3 (10, 15 and 20 mg L-1 con y sin surfactante a 0.05%. La

  14. The Path of Carbon in Photosynthesis II. Amino Acids

    Science.gov (United States)

    Stepka, W.; Benson, A. A.; Calvin, M.

    1948-05-25

    The radioactive amino acid's synthesized from C{sup 14}O{sub 2} by green algae both in the light and in the dark after CO{sub 2}-free preillumination have been separated and identified using paper chromatography and radioautography. The radioactive amino acids identified were aspartic acid, alanine and smaller amounts of 3- and 4-carbon amino acids. This finding as well as the total absence of radioactive glutamic acid substantiates the mechanism for reduction of CO{sub 2} previously postulated by members of this laboratory.

  15. Diffusion Coefficient of Tin(II) Methanesulfonate in Ionic Liquid and Methane Sulfonic Acid (MSA) Solvent

    Science.gov (United States)

    Yang, Kok Kee; Mahmoudian, M. R.; Ebadi, Mehdi; Koay, Hun Lee; Basirun, Wan Jeffrey

    2011-12-01

    Voltammetry and chronoamperometry for the electrodeposition of tin from Tin(II) methane sulfonate mixed with ionic liquid and methane sulfonate acid at room temperature was studied. Cyclic voltammetry shows redox waves of Tin(II), which proves that the electrodeposition of tin from Tin(II) methane sulfonate is a diffusion-controlled process. The diffusion coefficient of Tin(II) ions in the solvent mixture showed good agreement from both voltammetry and chronoamperometry results. The diffusion coefficient of Tin(II) in the mixture was much smaller than in aqueous solution, and it depends on the anion of the ionic liquid.

  16. Determination of Lemon YeIIow,Rhodamine B and Acid Orange Ⅱ in Cayenne Pepper Products by High Performance Liquid Chromatography%HPLC测定辣椒面中柠檬黄、罗丹明B和酸性橙Ⅱ

    Institute of Scientific and Technical Information of China (English)

    周良芹; 付大友; 谭文渊; 何于冰

    2016-01-01

    An analysis method is established for determination of 3 synthetic pigments including lemon yellow,Rhodamine B and acid orange Ⅱ in cayenne pepper products by high performance liquid chromatography with ultraviolet visible light detector.The samples are ultrasonically extracted using 50% methanol-water,and then use methanol and ammonium acetate for gradient elution.The retention time is used as qualitative analysis and peak area external standard is used as quantified detecting.The result shows that the linearity of lemon yellow,Rhodamine B and acid orange Ⅱ is better in range of 0.006~0.128 mg/mL,and R2≥0.9997.The average recoveries are 98.60%~102.58%,the relation standard deviation of detection is 1.6%~4.2% and the detection limit is 0.11~0.25 mg/kg.The method has the characteristics of high sensitivity,good repeatability, feasible and simple.It can be applied for the quantification of 3 synthetic pigments of lemon yellow, Rhodamine B and acid orange Ⅱin cayenne pepper products.%建立了一种同时测定辣椒制品中柠檬黄、罗丹明 B 和酸性橙Ⅱ的高效液相色谱方法。样品经50%的甲醇水溶液超声处理提取,以甲醇-乙酸铵溶液为流动相进行梯度洗脱,采用紫外检测器,保留时间定性,峰面积外标法定量检测。结果表明:上述3种色素在0.006~0.128 mg/mL的浓度范围内具有良好的线性关系,相关系数≥0.9997,加标回收率为98.60%~102.58%,相对标准偏差为1.6%~4.2%,检出限为0.11~0.25 mg/kg。该方法具有灵敏度高、重现性好、快速、简便的优点,适用于辣椒制品中柠檬黄、罗丹明B和酸性橙Ⅱ的同时测定。

  17. Characterizing plasma membrane H+-ATPase in two varieties of coffee leaf (Coffea arabica L.) and its interaction with an elicitor fraction from the orange rust fungus (H. vastatrix Berk and Br.) race II.

    Science.gov (United States)

    Osses, Luis R; Godoy, César A

    2006-04-01

    Early intercellular signaling in Coffea arabica L.-Hemileia vastatrix host-pathogen interaction was studied, using inside-out plasma membrane from two varieties of coffee leaf and a fungal fraction to determine the plant's biochemical responses. Microsomal pellets (100,000 x g) from the susceptible (Caturra) and resistant (Colombia) coffee leaf varieties were purified by partitioning in two-polymer DEX (6.3% w/w) and PEG (6.3% w/w) system aqueous phase. Fungal material was obtained from orange rust Hemileia vastatrix Berk and Br. race II urediospore germ tubes. Plasma membrane vesicles were preferentially localized to PEG phase, as indicated by its enzyme marker distribution. Both H(+)-ATPase activities displayed similar kinetic and biochemical characteristics, comparable to those described for P-type ATPases. Several enzymes may play pivotal roles in plants regarding early interaction with fungal elicitors. Studies of fungal fractions' effects on H(+)-ATPase and both varieties' proton pumping activities were thus carried out. Concentration as low as 0.1 Gluc eq. ml(-1) fungal fraction induced specific inhibition of H(+)-ATPase and the resistant variety's proton pumping activities. The present work describes characterizing the H(+)-ATPase plasma membrane from two Coffea arabica L. varieties (Caturra and Colombia) for the first time and the race specific inhibitory effect of a crude fungal fraction on both H(+)-ATPase and the resistant variety's proton pumping activities.

  18. An eleven amino acid residue deletion expands the substrate specificity of acetyl xylan esterase II (AXE II) from Penicillium purpurogenum

    Science.gov (United States)

    Colombres, Marcela; Garate, José A.; Lagos, Carlos F.; Araya-Secchi, Raúl; Norambuena, Patricia; Quiroz, Soledad; Larrondo, Luis; Pérez-Acle, Tomas; Eyzaguirre, Jaime

    2008-01-01

    The soft-rot fungus Penicillium purpurogenum secretes to the culture medium a variety of enzymes related to xylan biodegradation, among them three acetyl xylan esterases (AXE I, II and III). AXE II has 207 amino acids; it belongs to family 5 of the carbohydrate esterases and its structure has been determined by X-ray crystallography at 0.9 Å resolution (PDB 1G66). The enzyme possesses the α/β hydrolase fold and the catalytic triad typical of serine esterases (Ser90, His187 and Asp175). AXE II can hydrolyze esters of a large variety of alcohols, but it is restricted to short chain fatty acids. An analysis of its three-dimensional structure shows that a loop that covers the active site may be responsible for this strict specificity. Cutinase, an enzyme that hydrolyzes esters of long chain fatty acids and shows a structure similar to AXE II, lacks this loop. In order to generate an AXE II with this broader specificity, the preparation of a mutant lacking residues involving this loop (Gly104 to Ala114) was proposed. A set of molecular simulation experiments based on a comparative model of the mutant enzyme predicted a stable structure. Using site-directed mutagenesis, the loop's residues have been eliminated from the AXE II cDNA. The mutant protein has been expressed in Aspergillus nidulans A722 and Pichia pastoris, and it is active towards a range of fatty acid esters of up to at least 14 carbons. The availability of an esterase with broader specificity may have biotechnological applications for the synthesis of sugar esters.

  19. Electron Transfer Studies of Ruthenium(II) Complexes with Biologically Important Phenolic Acids and Tyrosine.

    Science.gov (United States)

    Rajeswari, Angusamy; Ramdass, Arumugam; Muthu Mareeswaran, Paulpandian; Rajagopal, Seenivasan

    2016-03-01

    The ruthenium(II) complexes having 2,2'-bipyridine and phenanthroline derivatives are synthesized and characterized. The photophysical properties of these complexes at pH 12.5 are studied. The electron transfer reaction of biologically important phenolic acids and tyrosine are studied using absorption, emission and transient absorption spectral techniques. Semiclassical theory is applied to calculate the rate of electron transfer between ruthenium(II) complexes and biologically important phenolic acids.

  20. Fe(II) Oxidation and Sources of Acidity on Mars

    Science.gov (United States)

    Niles, P. B.; Peretyazkho, T. S.; Sutter, B.

    2017-01-01

    There is an apparent paradox be-tween the evidence that aqueous environments on Mars were predominantly acidic, and the fact that Mars is predominantly a basaltic (and olivine-rich) planet. The problem being that basalt and olivine will act to neutralize acidic solutions they come into contact with, and that there is a lot more basaltic crust on Mars than water or acid. This is especially true if there is an appreciable amount of water available to bring the acid in contact with the basaltic crust. Several hypotheses for ancient mar-tian environments call on long lived groundwater and aqueous systems.

  1. Alkyl sulfonic acide hydrazides: Synthesis, characterization, computational studies and anticancer, antibacterial, anticarbonic anhydrase II (hCA II) activities

    Science.gov (United States)

    O. Ozdemir, Ummuhan; İlbiz, Firdevs; Balaban Gunduzalp, Ayla; Ozbek, Neslihan; Karagoz Genç, Zuhal; Hamurcu, Fatma; Tekin, Suat

    2015-11-01

    Methane sulfonic acide hydrazide, CH3SO2NHNH2 (1), ethane sulfonic acide hydrazide, CH3CH2SO2NHNH2 (2), propane sulfonic acide hydrazide, CH3CH2CH2SO2NHNH2 (3) and butane sulfonic acide hydrazide, CH3CH2CH2CH2SO2NHNH2 (4) have been synthesized as homologous series and characterized by using elemental analysis, spectrophotometric methods (1H-13C NMR, FT-IR, LC-MS). In order to gain insight into the structure of the compounds, we have performed computational studies by using 6-311G(d, p) functional in which B3LYP functional were implemented. The geometry of the sulfonic acide hydrazides were optimized at the DFT method with Gaussian 09 program package. A conformational analysis of compounds were performed by using NMR theoretical calculations with DFT/B3LYP/6-311++G(2d, 2p) level of theory by applying the (GIAO) approach. The anticancer activities of these compounds on MCF-7 human breast cancer cell line investigated by comparing IC50 values. The antibacterial activities of synthesized compounds were studied against Gram positive bacteria; Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Bacillus cereus NRRL-B-3711, Enterococcus faecalis ATCC 29212 and Gram negative bacteria; Escherichia coli ATCC 11230, Pseudomonas aeruginosa ATCC 15442, Klebsiella pneumonia ATCC 70063 by using the disc diffusion method. The inhibition activities of these compounds on carbonic anhydrase II enzyme (hCA II) have been investigated by comparing IC50 and Ki values. The biological activity screening shows that butane sulfonic acide hydrazide (4) has more activity than the others against tested breast cancer cell lines MCF-7, Gram negative/Gram positive bacteria and carbonic anhydrase II (hCA II) isoenzyme.

  2. Relative abundance of chemical forms of Cu(II) and Cd(II) on soybean roots as influenced by pH, cations and organic acids

    Science.gov (United States)

    Zhou, Qin; Liu, Zhao-Dong; Liu, Yuan; Jiang, Jun; Xu, Ren-Kou

    2016-11-01

    Little information is available on chemical forms of heavy metals on integrate plant roots. KNO3 (1 M), 0.05M EDTA at pH6 and 0.01 M HCl were used sequentially to extract the exchangeable, complexed and precipitated forms of Cu(II) and Cd(II) from soybean roots and then to investigate chemical form distribution of Cu(II) and Cd(II) on soybean roots. Cu(II) and Cd(II) adsorbed on soybean roots were mainly exchangeable form, followed by complexed form, while their precipitated forms were very low under acidic conditions. Soybean roots had a higher adsorption affinity to Cu(II) than Cd(II), leading to higher toxic of Cu(II) than Cd(II). An increase in solution pH increased negative charge on soybean and thus increased exchangeable Cu(II) and Cd(II) on the roots. Ca2+, Mg2+ and NH4+ reduced exchangeable Cu(II) and Cd(II) levels on soybean roots and these cations showed greater effects on Cd(II) than Cu(II) due to greater adsorption affinity of the roots to Cu(II) than Cd(II). L-malic and citric acids decreased exchangeable and complexed Cu(II) on soybean roots. In conclusion, Cu(II) and Cd(II) mainly existed as exchangeable and complexed forms on soybean roots. Ca2+ and Mg2+ cations and citric and L-malic acids can potentially alleviate Cu(II) and Cd(II) toxicity to plants.

  3. A nucleic acid probe labeled with desmethyl thiazole orange: a new type of hybridization-sensitive fluorescent oligonucleotide for live-cell RNA imaging.

    Science.gov (United States)

    Okamoto, Akimitsu; Sugizaki, Kaori; Yuki, Mizue; Yanagisawa, Hiroyuki; Ikeda, Shuji; Sueoka, Takuma; Hayashi, Gosuke; Wang, Dan Ohtan

    2013-01-14

    A new fluorescent nucleotide with desmethyl thiazole orange dyes, D'(505), has been developed for expansion of the function of fluorescent probes for live-cell RNA imaging. The nucleoside unit of D'(505) for DNA autosynthesis was soluble in organic solvents, which made the preparation of nucleoside units and the reactions in the cycles of DNA synthesis more efficient. The dyes of D'(505)-containing oligodeoxynucleotide were protonated below pH 7 and the oligodeoxynucleotide exhibited hybridization-sensitive fluorescence emission through the control of excitonic interactions of the dyes of D'(505). The simplified procedure and effective hybridization-sensitive fluorescence emission produced multicolored hybridization-sensitive fluorescent probes, which were useful for live-cell RNA imaging. The acceptor-bleaching method gave us information on RNA in a specific cell among many living cells.

  4. Biological iron(II) oxidation as pre-treatment to limestone neutralisation of acid water

    CSIR Research Space (South Africa)

    Maree, JP

    1998-01-01

    Full Text Available Iron (II) should be oxidised to iron (III) before the neutralisation of acid water with limestone, otherwise the oxidation will occur downstream of the neutralisation plant with the formation of acid (reactions 1 and 2). This study aimed...

  5. Chemiluminescence of the peroxomonosulphate-cobalt(II)-aliphatic monocarboxylic acids system.

    Science.gov (United States)

    Wang, Min; Zhao, Lixia; Lin, Jin-Ming

    2007-01-01

    A weak chemiluminescence (CL) emission was observed due to the production of singlet oxygen ((1)O(2)) during the decomposition of peroxomonosulphate (HSO(5)(-)) catalysed by cobalt(II). Low molecular mass aliphatic monocarboxylic acids, such as formic, acetic, propionic, butyric and valeric acids, influenced the CL emission, and the reaction of aliphatic monocarboxylic acids with HSO(5)(-)/Co(2+) solution was further investigated using a flow injection analysis (FIA) CL method. The results indicated that the CL intensities of aliphatic monocarboxylic acids were improved with increase in the carbon chain length in the potassium peroxomonosulphate-cobalt(II) sulphate system. Generation of singlet oxygen was confirmed by the fact that the CL emission of aliphatic monocarboxylic acids with the HSO(5)(-)/Co(2+) solution was quenched by NaN(3), and from the CL spectrum of the reaction system. Additionally, a possible mechanism of aliphatic monocarboxylic acids CL emission enhancement was proposed.

  6. Enhanced removal of Hg(II) from acidic aqueous solution using thiol-functionalized biomass.

    Science.gov (United States)

    Chai, Liyuan; Wang, Qingwei; Li, Qingzhu; Yang, Zhihui; Wang, Yunyan

    2010-01-01

    Spent grain, the low-cost and abundant biomass produced in the brewing industry, was functionalized with thiol groups to be used as an adsorbent for Hg(II) removal from acidic aqueous solution. The adsorbents were characterized by the energy-dispersive X-ray analysis (EDAX) and Fourier transform infrared (FTIR) spectroscopy. Optimum pH for Hg(II) adsorption onto the thiol-functionalized spent grain (TFSG) was 2.0. The equilibrium and kinetics of the adsorption of Hg(II) onto TFSG from acidic aqueous solution were investigated. From the Langmuir isotherm model the maximum adsorption capacity of TFSG for Hg(II) was found to be 221.73 mg g(-1), which was higher than that of most various adsorbents reported in literature. Moreover, the adsorption of Hg(II) onto TFSG followed pseudo-second-order kinetic model.

  7. The vitamin C content of orange juice packed in an oxygen scavenger material

    NARCIS (Netherlands)

    Zerdin, K.; Rooney, M.L.; Vermuë, J.

    2003-01-01

    A storage study of orange juice packed in oxygen scavenging (OS) film and oxygen barrier film was conducted to determine the extent of ascorbic acid loss due to oxygen as a function of time and temperature. The initial concentration of ascorbic acid in the orange juice was 374 mg/l and this was foun

  8. The vitamin C content of orange juice packed in an oxygen scavenger material

    NARCIS (Netherlands)

    Zerdin, K.; Rooney, M.L.; Vermuë, J.

    2003-01-01

    A storage study of orange juice packed in oxygen scavenging (OS) film and oxygen barrier film was conducted to determine the extent of ascorbic acid loss due to oxygen as a function of time and temperature. The initial concentration of ascorbic acid in the orange juice was 374 mg/l and this was

  9. Nitrilotriacetic acid functionalized Adansonia digitata biosorbent: Preparation, characterization and sorption of Pb (II and Cu (II pollutants from aqueous solution

    Directory of Open Access Journals (Sweden)

    Adewale Adewuyi

    2016-11-01

    Full Text Available Nitrilotriacetic acid functionalized Adansonia digitata (NFAD biosorbent has been synthesized using a simple and novel method. NFAD was characterized by X-ray Diffraction analysis technique (XRD, Scanning Electron Microscopy (SEM, Brunauer-Emmett-Teller (BET surface area analyzer, Fourier Transform Infrared spectrometer (FTIR, particle size dispersion, zeta potential, elemental analysis (CHNS/O analyzer, thermogravimetric analysis (TGA, differential thermal analysis (DTA, derivative thermogravimetric analysis (DTG and energy dispersive spectroscopy (EDS. The ability of NFAD as biosorbent was evaluated for the removal of Pb (II and Cu (II ions from aqueous solutions. The particle distribution of NFAD was found to be monomodal while SEM revealed the surface to be heterogeneous. The adsorption capacity of NFAD toward Pb (II ions was 54.417 mg/g while that of Cu (II ions was found to be 9.349 mg/g. The adsorption of these metals was found to be monolayer, second-order-kinetic, and controlled by both intra-particle diffusion and liquid film diffusion. The results of this study were compared better than some reported biosorbents in the literature. The current study has revealed NFAD to be an effective biosorbent for the removal of Pb (II and Cu (II from aqueous solution.

  10. Nitrilotriacetic acid functionalized Adansonia digitata biosorbent: Preparation, characterization and sorption of Pb (II) and Cu (II) pollutants from aqueous solution.

    Science.gov (United States)

    Adewuyi, Adewale; Pereira, Fabiano Vargas

    2016-11-01

    Nitrilotriacetic acid functionalized Adansonia digitata (NFAD) biosorbent has been synthesized using a simple and novel method. NFAD was characterized by X-ray Diffraction analysis technique (XRD), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analyzer, Fourier Transform Infrared spectrometer (FTIR), particle size dispersion, zeta potential, elemental analysis (CHNS/O analyzer), thermogravimetric analysis (TGA), differential thermal analysis (DTA), derivative thermogravimetric analysis (DTG) and energy dispersive spectroscopy (EDS). The ability of NFAD as biosorbent was evaluated for the removal of Pb (II) and Cu (II) ions from aqueous solutions. The particle distribution of NFAD was found to be monomodal while SEM revealed the surface to be heterogeneous. The adsorption capacity of NFAD toward Pb (II) ions was 54.417 mg/g while that of Cu (II) ions was found to be 9.349 mg/g. The adsorption of these metals was found to be monolayer, second-order-kinetic, and controlled by both intra-particle diffusion and liquid film diffusion. The results of this study were compared better than some reported biosorbents in the literature. The current study has revealed NFAD to be an effective biosorbent for the removal of Pb (II) and Cu (II) from aqueous solution.

  11. Chemodynamics of soft nanoparticulate complexes: Cu(II) and Ni(II) complexes with fulvic acids and aquatic humic acids

    NARCIS (Netherlands)

    Town, R.M.; Leeuwen, van H.P.; Buffle, J.

    2012-01-01

    The dynamics of metal complexation by small humic substances (fulvic acid and aquatic humic acid, collectively denoted as "fulvic-like substance", FS) are explored within the framework of concepts recently developed for soft nanoparticulate complexants. From a comprehensive collection of published e

  12. Structures of polynuclear complexes of palladium(II) and platinum(II) formed by slow hydrolysis in acidic aqueous solution.

    Science.gov (United States)

    Torapava, Natallia; Elding, Lars I; Mändar, Hugo; Roosalu, Kaspar; Persson, Ingmar

    2013-06-07

    The aqua ions of palladium(II) and platinum(II) undergo extremely slow hydrolysis in strongly acidic aqueous solution, resulting in polynuclear complexes. The size and structures of these species have been determined by EXAFS and small angle X-ray scattering, SAXS. For palladium(II), the EXAFS data show that the Pd-O and Pd···Pd distances are identical to those of crystalline palladium(II) oxide, but the intensities of the Pd···Pd distances in the Fourier transform at 3.04 and 3.42 Å are significantly lower compared to those of crystalline PdO. Furthermore, no Pd···Pd distances beyond 4 Å are observed. These observations strongly indicate that the polynuclear palladium(II) complexes are oxido- and hydroxido-bridged species with the same core structure as solid palladium(II) oxide. Based on the number of Pd···Pd distances, as derived from the EXAFS data, their size can be estimated to be approximately two unit cells, or ca. 1.0 nm(3). For platinum(II), EXAFS data of the polynuclear species formed in the slow hydrolysis process show Pt-O and Pt···Pt distances identical to those of amorphous platinum(II) oxide, precipitating from the solution studied. The Pt···Pt distances are somewhat different from those reported for crystalline platinum(II) oxide. The polynuclear platinum(II) complexes have a similar structure to the palladium ones, but they are somewhat larger, with an estimated diameter of 1.5-3.0 nm. It has not been possible to precipitate any of these species by ultracentrifugation. They are detectable by SAXS, indicating diameters between 0.7 and 2 nm, in excellent agreement with the EXAFS observations. The number of oxido- relative to hydroxido bridges will increase with increasing size of the complex. The charge of the complexes will remain about the same, +4, at growth, with approximate formulas [Pd10O4(OH)8(H2O)12](4+) and [Pt14O8(OH)8(H2O)12](4+) for complexes with a size of 2 and 3 unit cells of the corresponding solid metal oxide

  13. Degradation of methyl orange through synergistic effect of zirconia nanotubes and ultrasonic wave.

    Science.gov (United States)

    Zhao, Jianling; Wang, Xixin; Zhang, Libin; Hou, Xiaorui; Li, Ying; Tang, Chengchun

    2011-04-15

    Zirconia nanotubes with a length of 25 μm, inner diameter of 80 nm, and wall thickness of 35 nm were prepared by anodization method in mixture of formamide and glycerol (volume ratio = 1:1) containing 1 wt% NH(4)F and 1 wt% H(2)O. Experiments showed that zirconia nanotubes and ultrasonic wave had synergistic degradation effect for methyl orange and the efficiency of ultrasonic wave increased by more than 7 times. The decolorization percentage was influenced by pH value of the solution. Methyl orange was easy to be degraded in acidic solution. The decolorization percentage of methyl orange reached 97.6% when degraded for 8h in 20mg/L methyl orange solution with optimal pH value 2. The reason of synergistic degradation effect for methyl orange might be that adsorption of methyl orange onto zirconia nanotubes resulted in the easy degradation of the methyl orange through ultrasonic wave.

  14. Synthesis and characterization of Co(II), Ni(II), Cu(II) and Zn(II) complexes of tridentate Schiff base derived from vanillin and DL-α-aminobutyric acid

    Science.gov (United States)

    Nair, M. Sivasankaran; Joseyphus, R. Selwin

    2008-09-01

    Co(II), Ni(II), Cu(II) and Zn(II) complexes of the Schiff base derived from vanillin and DL-α-aminobutyric acid were synthesized and characterized by elemental analysis, IR, electronic spectra, conductance measurements, magnetic measurements, powder XRD and biological activity. The analytical data show the composition of the metal complex to be [ML(H 2O)], where L is the Schiff base ligand. The conductance data indicate that all the complexes are non-electrolytes. IR results demonstrate the tridentate binding of the Schiff base ligand involving azomethine nitrogen, phenolic oxygen and carboxylato oxygen atoms. The IR data also indicate the coordination of a water molecule with the metal ion in the complex. The electronic spectral measurements show that Co(II) and Ni(II) complexes have tetrahedral geometry, while Cu(II) complex has square planar geometry. The powder XRD studies indicate that Co(II) and Cu(II) complexes are amorphous, whereas Ni(II) and Zn(II) complexes are crystalline in nature. Magnetic measurements show that Co(II), Ni(II) and Cu(II) complexes have paramagnetic behaviour. Antibacterial results indicated that the metal complexes are more active than the ligand.

  15. Equilibrium, thermoanalytical and spectroscopic studies to characterize phytic acid complexes with Mn(II) and Co(II)

    Energy Technology Data Exchange (ETDEWEB)

    Carli, Ligia de; Schnitzler, Egon; Rosso, Neiva Deliberali [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil). Dept. de Quimica], e-mail: ndrosso@uepg.br; Ionashiro, Massao [Universidade Estadual Paulista (UNESP), Araraquara, SP (Brazil). Inst. de Quimica; Szpoganicz, Bruno [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Quimica

    2009-07-01

    Potentiometric studies were carried out to determine the binding degree of phytic acid with Co(II) and Mn(II) ions, in the absence of dioxygen. Equilibrium constants for all major complexes formed are reported, and the results are presented in the form of distribution diagrams showing the concentrations of individual complexes as a function of pH. The formation constants of the complexes show higher values for the species in which the ligand was more deprotonated. Potentiometric data indicates that the species [MH{sub 4}L]{sup 6-}, was totally formed at pH 7.0 and the complexes were synthesized from this data. A solid state complex of Mn(II) and Co(II) with phytic acid was synthesized. Thermogravimetry, differential scanning calorimetry, and infrared spectroscopy were used to investigate and characterize the thermal behavior of these compounds. The results led to information on the composition, dehydration, thermal stability and thermal decomposition of the isolated complexes. (author)

  16. Anti-oxidant, in vitro, in vivo anti-inflammatory activity and antiproliferative activity of mefenamic acid and its metal complexes with manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II).

    Science.gov (United States)

    Kovala-Demertzi, Dimitra; Hadjipavlou-Litina, Dimitra; Staninska, Malgorzata; Primikiri, Alexandra; Kotoglou, Chronis; Demertzis, Mavroudis A

    2009-06-01

    Some new complexes of mefenamic acid with potentially interesting biological activity are described. The complexes of mefenamic acid [Mn(mef)(2)(H(2)O)(2)], 1, [Co(mef)(2)(H(2)O)(2)], 2, [Ni(mef)(2)(H(2)O)(2)], 3, [Cu(mef)(2)(H(2)O)](2), 4 and [Zn(mef)(2)], 5, were prepared by the reaction of mefenamic acid, a potent anti-inflammatory drug with metal salts. Optical and infrared spectral data of these new complexes are reported. Monomeric six-coordinated species were isolated in the solid state for Mn(II), Ni(II) and Co(II), dimeric five-coordinated for Cu(II) and monomeric four-coordinated for Zn(II). In DMF or CHCl(3) solution the coordination number is retained and the coordinated molecules of water are replaced by solvent molecules. The anti-oxidant properties of the complexes were evaluated using the 1,1-diphenyl-2-picrylhydrazyl, DPPH, free radical scavenging assay. The scavenging activities of the complexes were measured and compared with those of the free drug and vitamin C. We have explored their ability to inhibit soybean lipoxygenase, beta-glucuronidase and trypsin- induced proteolysis. The complex [Mn(mef)(2)(H(2)O)(2)] exhibits the highest antioxidant activity and the highest inhibitory effect against the soybean lipogygenase (LOX), properties that are not demonstrated by mefenamic acid. Their inhibitory effects on rat paw edema induced by Carrageenan was studied and compared with those of mefenamic acid. The complex [Zn(mef)(2)] exhibited a strong inhibitory effect at 0.1 mmol/Kg B.W. (81.5 +/- 1.3% inhibition), superior to the inhibition induced by mefenamic acid at the same dose (61.5 +/- 2.3% inhibition). Mefenamic acid and its metal complexes have been evaluated for antiproliferative activity in vitro against the cells of three human cancer cell lines: MCF-7 (human breast cancer cell line), T24 (bladder cancer cell line), A-549 (non-small cell lung carcinoma) and a mouse fibroblast L-929 cell line. The copper(II) complex displays against T24, MCF-7

  17. Effect of Grafted Hydroquinone on the Acid-Base Properties of Poly(acrylic acid) in the Presence of Copper (II)

    OpenAIRE

    Nabila Bensacia; Saâd Moulay; François Garin; Ioana Fechete; Anne Boos

    2015-01-01

    Potentiometric titration of poly(acrylic acid) and hydroquinone-functionalized poly(acrylic acid) was conducted in the presence of copper (II). The effects of hydroquinone functionalizing and copper (II) complexing on the potentiometric titration of poly(acrylic acid) were studied in an ionic environment and in its absence. Henderson-Hasselbalch equation was applied to assess its validity for this titration. Coordination number and the stability constants of the copper- (II-)complexed polymer...

  18. Study of sepiolite from Goles (Kosovo, Yugoslavia. II. Acid activation

    Directory of Open Access Journals (Sweden)

    DRAGOMIR VITOROVIC

    2002-07-01

    Full Text Available The changes in the pore structure and adsorption properties of sepiolite from Gole{ resulting from treatment with 4 M HCl for various periods of time were investigated. The BET method specific surface areas, pore volumes and f – plots were determined by nitrogen adsorption. The surface area progressively increased during the 70 hours of acid treatment, when a maximum was attained. The differences in the adsorption properties of the original and the acid treated sepiolite were evaluated by comparison of adsorption isotherms obtained with benzene, n-hexane, methanol and isooctane. The enhanced adsorption of isooctane was of great interest, since the sorption of this compound on natural sepiolites is generally very limited. The results suggest that chemical treatment of sepiolite with 4 M HCl for 70 h produces an adsorbent of optimal porosity and other adsorption properties.

  19. Functionalization of conducting polymer with novel Co(II) complex: Electroanalysis of ascorbic acid

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, Swati [School of Materials Science and Technology, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India); Prakash, Rajiv, E-mail: rajivprakash12@yahoo.com [School of Materials Science and Technology, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India)

    2010-06-15

    We report for the first time the functionalization of a conducting polymer with a metal complex in order to develop a new type of catalytic material exhibiting better electronic communication through their delocalized {pi} electrons. The Co(II) complex having hydroxyl group as functional moiety is chemically coupled with carboxyl group of polyanthranilic acid which itself is a self doped conducting polymer. The covalent linkage between Co(II) and -OH group is confirmed using UV-vis, FT-IR and NMR spectroscopic techniques. The Co(II) complex functionalized polymer does exhibit excellent redox behavior and stability with mixed properties of Co(II) complex and {pi}-conjugated polymer. The material possesses potential benefits in sensors/biosensor applications and it is demonstrated for the electroanalysis of ascorbic acid at a level of nano molar concentration.

  20. Removal Cu(II ions from water using sulphuric acid treated Lagenaria vulgaris Shell (Cucurbitaceae

    Directory of Open Access Journals (Sweden)

    Ljupković, R.B.

    2011-09-01

    Full Text Available Removal of Cu(II ions from water solutions by sulphuric acid treated Lagenaria vulgaris shell (ccLVB was studied. Batch experiments were done by shaking a fixed mass of biosorbent (1.0 g with 250 cm3 of 50.0 mg dm–3 Cu(II solutions, at pH ranged from 2 up to 6. Metal concentration in the filtrates as well as in the initial solution was determined by flame atomic absorption spectrometry. Results show that efficiency of Cu(II ions uptake by sulphuric acid treated Lagenaria vulgaris shell is significantly greater than raw Lagenaria vulgaris biosorbent. In addition, there is no significant effect of initial pH of solution on Cu(II ions uptake by ccLVB and obtained biosorbent can be applied in a wide range of pH.

  1. Ni(ii)-catalyzed asymmetric addition of arylboronic acids to cyclic imines.

    Science.gov (United States)

    Quan, Mao; Tang, Liang; Shen, Jiaqi; Yang, Guoqiang; Zhang, Wanbin

    2017-01-03

    A Ni(ii)-catalyzed asymmetric addition of arylboronic acids to cyclic aldimines and ketimines is reported. Our tropos phosphine-oxazoline biphenyl ligand is crucial for the high catalytic activity, which coordinates to Ni(ii) to form a complex with a single axial configuration. The desired chiral amine products could be prepared with excellent yields (up to 99%) and enantioselectivities (up to 99.8%) under mild reaction conditions.

  2. Semi-empirical chemical model for indirect advanced oxidation of Acid Orange 7 using an unmodified carbon fabric cathode for H2O2 production in an electrochemical reactor.

    Science.gov (United States)

    Ramírez, B; Rondán, V; Ortiz-Hernández, L; Silva-Martínez, S; Alvarez-Gallegos, A

    2016-04-15

    A commercial Unidirectional Carbon Fabric piece was used to design an electrode for the cathodic O2 reduction reaction in a divided (by a Nafion(®) 117 membrane) parallel plate reactor. The anode was a commercial stainless steel mesh. Under this approach it is feasible to produce H2O2 at low energy (2.08 kWh kg(-1) H2O2) in low ionic acidic medium. In the catholyte side the H2O2 can be activated with Fe(2+) to develop the Fenton reagent. It was found that Acid Orange 7 (AO7) indirect oxidation (in the concentration range of 0.12-0.24 mM) by Fenton chemistry follows a first order kinetic equation. The energy required for 0.24 mM AO7 degradation is 1.04 kWhm(-3). From each experimental AO7 oxidation the main parameters (a, mM and k, min(-1)) of the first order kinetic equation are obtained. These parameters can be correlated with AO7 concentration in the concentration range studied. Based on this method a semi-empirical chemical model was developed to predict the AO7 abatement, by means of Fenton chemistry. Good AO7 oxidation predictions can be made in the concentration range studied. A detailed discussion of the energy required for oxidizing AO7 and the accuracy of the chemical model to predict its oxidation is included in this paper.

  3. Evaluation of genotoxicity and pro-oxidant effect of the azo dyes: acids yellow 17, violet 7 and orange 52, and of their degradation products by Pseudomonas putida mt-2.

    Science.gov (United States)

    Ben Mansour, Hedi; Corroler, David; Barillier, Daniel; Ghedira, Kamel; Chekir, Leila; Mosrati, Ridha

    2007-09-01

    Acids yellow 17, violet 7 and orange 52, very important commercial azo dyes used in the textile, food, paper and cosmetic industries, were degraded by Pseudomonas putida mt-2 at concentrations up to 100mg/l. The culture media was completely decolorized under static incubation for 60 h, this faster than under continuous shaking incubation. SOS chromotest using Escherichia coli PQ37, with and without metabolic activation (S-9 preparations), was used to assess genotoxicity potential of these dyes before and after biodegradation. None of these dyes or their metabolites was found to be genotoxic in the absence of "Araclor-Induced rat liver microsome" preparations (S-9). However, in presence of the preparation S-9, the genotoxicity of the biodegradation products was highlighted. Metabolites resulting from static cultures were more genotoxic than those obtained in shaken conditions. In addition to genotoxic effects, metabolites have shown a significant ability to induce the formation of superoxide free radical anion (O(2)(*-)). The toxicities generated by the pure azo dyes and the pure azo-reduction products (sulfanilic acid, N,N'-dimethyl-p-phenylenediamine and 4'-aminoacetanilid) were compared. These results suggest that P. putida mt-2 degrades the studied azo dyes in two steps: an azo-reduction followed by an oxygen-dependent metabolization. Some of the derived metabolites would be responsible of genotoxicity and metabolic toxicity.

  4. Cloning and sequence analysis of putative type II fatty acid synthase genes from Arachis hypogaea L.

    Indian Academy of Sciences (India)

    Meng-Jun Li; Ai-Qin Li; Han Xia; Chuan-Zhi Zhao; Chang-Sheng Li; Shu-Bo Wan; Yu-Ping Bi; Xing-Jun Wang

    2009-06-01

    The cultivated peanut is a valuable source of dietary oil and ranks fifth among the world oil crops. Plant fatty acid biosynthesis is catalysed by type II fatty acid synthase (FAS) in plastids and mitochondria. By constructing a full-length cDNA library derived from immature peanut seeds and homology-based cloning, candidate genes of acyl carrier protein (ACP), malonyl-CoA:ACP transacylase, -ketoacyl-ACP synthase (I, II, III), -ketoacyl-ACP reductase, -hydroxyacyl-ACP dehydrase and enoyl-ACP reductase were isolated. Sequence alignments revealed that primary structures of type II FAS enzymes were highly conserved in higher plants and the catalytic residues were strictly conserved in Escherichia coli and higher plants. Homologue numbers of each type II FAS gene expressing in developing peanut seeds varied from 1 in KASII, KASIII and HD to 5 in ENR. The number of single-nucleotide polymorphisms (SNPs) was quite different in each gene. Peanut type II FAS genes were predicted to target plastids except ACP2 and ACP3. The results suggested that peanut may contain two type II FAS systems in plastids and mitochondria. The type II FAS enzymes in higher plants may have similar functions as those in E. coli.

  5. Cloning and sequence analysis of putative type II fatty acid synthase genes from Arachis hypogaea L.

    Science.gov (United States)

    Li, Meng-Jun; Li, Ai-Qin; Xia, Han; Zhao, Chuan-Zhi; Li, Chang-Sheng; Wan, Shu-Bo; Bi, Yu-Ping; Wang, Xing-Jun

    2009-06-01

    The cultivated peanut is a valuable source of dietary oil and ranks fifth among the world oil crops. Plant fatty acid biosynthesis is catalysed by type II fatty acid synthase (FAS) in plastids and mitochondria. By constructing a full-length cDNA library derived from immature peanut seeds and homology-based cloning, candidate genes of acyl carrier protein (ACP), malonyl-CoA:ACP transacylase, beta-ketoacyl-ACP synthase (I, II, III), beta-ketoacyl-ACP reductase, beta-hydroxyacyl-ACP dehydrase and enoyl-ACP reductase were isolated. Sequence alignments revealed that primary structures of type II FAS enzymes were highly conserved in higher plants and the catalytic residues were strictly conserved in Escherichia coli and higher plants. Homologue numbers of each type II FAS gene expressing in developing peanut seeds varied from 1 in KASII, KASIII and HD to 5 in ENR. The number of single-nucleotide polymorphisms (SNPs) was quite different in each gene. Peanut type II FAS genes were predicted to target plastids except ACP2 and ACP3. The results suggested that peanut may contain two type II FAS systems in plastids and mitochondria. The type II FAS enzymes in higher plants may have similar functions as those in E. coli.

  6. Influence of humic acid on adsorption of Hg(II) by vermiculite.

    Science.gov (United States)

    do Nascimento, Fernando Henrique; Masini, Jorge Cesar

    2014-10-01

    Geochemical mobility of Hg(II) species is strongly affected by the interactions of these compounds with naturally occurring adsorbents such as humic acids, clay minerals, oxides, etc. Interactions among these sorbents affect their affinity for Hg(II) and a full understanding of these processes is still lacking. The present work describes the influence of a humic acid (HA) sample on the adsorption of Hg(II) by vermiculite (VT). Adsorption isotherms were constructed to evaluate the affinity of Hg(II) by VT, HA, VT modified with humic acid (VT-HA), and VT-HA in presence of soluble humic acid (VT-HA + HA). All experiments were made at pH 6.0 ± 0.1 in 0.02 M NaNO3 and 25.0 ± 0.5 °C for initial Hg(II) concentrations from 1.0 to 100 μM. Determinations of Hg(II) were made by square wave voltammetry automated by sequential injection analysis, an approach that enables the determination of the free plus labile fractions of Hg(II) in HA suspensions without the need for laborious separation steps. The adsorption isotherms were fitted to Langmuir and Freundlich equations, showing that HA was the material with the higher adsorption capacity (537 ± 30 μmol g(-1)) in comparison with VT and VT-HA (44 ± 3 and 51 ± 11 μmol g(-1), respectively). Adsorption order was HA > VT-HA + HA > VT = VT-HA. At pH 6.0 the interaction of HA with VT is weak and only 14% of C initially added to the suspension was effectively retained by the mineral. Desorption of Hg(II) in acidic medium (0.05 M HCl) was higher in binary (VT-HA) and ternary (VT-HA + HA) systems in comparison with that of VT and HA alone, suggesting that interactions between VT and HA are facilitated in acidic medium, weakening the binding to Hg(II).

  7. Cu(II) binding by a pH-fractionated fulvic acid

    Science.gov (United States)

    Brown, G.K.; Cabaniss, S.E.; MacCarthy, P.; Leenheer, J.A.

    1999-01-01

    The relationship between acidity, Cu(II) binding and sorption to XAD resin was examined using Suwannee River fulvic acid (SRFA). The work was based on the hypothesis that fractions of SRFA eluted from an XAD column at various pH's from 1.0 to 12.0 would show systematic variations in acidity and possibly aromaticity which in turn would lead to different Cu(II) binding properties. We measured equilibrium Cu(II) binding to these fractions using Cu2+ ion-selective electrode (ISE) potentiometry at pH 6.0. Several model ligands were also examined, including cyclopentane-1,2,3,4-tetracarboxylic acid (CP-TCA) and tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THF-TCA), the latter binding Cu(II) much more strongly as a consequence of the ether linkage. The SRFA Cu(II) binding properties agreed with previous work at high ionic strength, and binding was enhanced substantially at lower ionic strength, in agreement with Poisson-Boltzmann predictions for small spheres. Determining Cu binding constants (K(i)) by non-linear regression with total ligand concentrations (L(Ti)) taken from previous work, the fractions eluted at varying pH had K(i) similar to the unfractionated SRFA, with a maximum enhancement of 0.50 log units. We conclude that variable-pH elution from XAD does not isolate significantly strong (or weak) Cu(II)-binding components from the SRFA mixture. Copyright (C) 1999 Elsevier Science B.V.

  8. Prebiotic syntheses of vitamin coenzymes: II. Pantoic acid, pantothenic acid, and the composition of coenzyme A

    Science.gov (United States)

    Miller, S. L.; Schlesinger, G.

    1993-01-01

    Pantoic acid can by synthesized in good prebiotic yield from isobutyraldehyde or alpha-ketoisovaleric acid + H2CO + HCN. Isobutyraldehyde is the Strecker precursor to valine and alpha-ketoisovaleric acid is the valine transamination product. Mg2+ and Ca2+ as well as several transition metals are catalysts for the alpha-ketoisovaleric acid reaction. Pantothenic acid is produced from pantoyl lactone (easily formed from pantoic acid) and the relatively high concentrations of beta-alanine that would be formed on drying prebiotic amino acid mixtures. There is no selectivity for this reaction over glycine, alanine, or gamma-amino butyric acid. The components of coenzyme A are discussed in terms of ease of prebiotic formation and stability and are shown to be plausible choices, but many other compounds are possible. The gamma-OH of pantoic acid needs to be capped to prevent decomposition of pantothenic acid. These results suggest that coenzyme A function was important in the earliest metabolic pathways and that the coenzyme A precursor contained most of the components of the present coenzyme.

  9. Effect of Grafted Hydroquinone on the Acid-Base Properties of Poly(acrylic acid in the Presence of Copper (II

    Directory of Open Access Journals (Sweden)

    Nabila Bensacia

    2015-01-01

    Full Text Available Potentiometric titration of poly(acrylic acid and hydroquinone-functionalized poly(acrylic acid was conducted in the presence of copper (II. The effects of hydroquinone functionalizing and copper (II complexing on the potentiometric titration of poly(acrylic acid were studied in an ionic environment and in its absence. Henderson-Hasselbalch equation was applied to assess its validity for this titration. Coordination number and the stability constants of the copper- (II-complexed polymers were determined, and results showed the formation of mostly monodentate and bidentate copper- (II-polymer complexes.

  10. Au@SiO_2核壳结构-表面增强拉曼光谱原位检测食品中的酸性橙Ⅱ%In Situ Detection of Acid Orange Ⅱ in Food Based on Shell-Isolated Au@SiO_2 Nanoparticle-Enhanced Raman Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    张宗绵; 刘睿; 徐敦明; 刘景富

    2012-01-01

    As a strong carcinogen to humans,acid orange Ⅱ is forbidden to be added as an additive into foodstuff.Because the foods colored with acid orange Ⅱ showed stable and colorful appearance,acid orange Ⅱ is broadly utilized by illegally producers for their low costing.Currently available analytical methods for acid orange Ⅱ are mainly based on fluorescence and liquid chromatography,which are time-consuming and tedious as acid orange Ⅱ has to be extracted from the samples before determination.For efficient detection and insurance of food safety,it is urgent to develop fast and low-cost in situ assay methods for field detection of acid orange Ⅱ on foods.In this study,shell-isolated Au@SiO2 nanoparticles is prepared for detecting acid orange Ⅱ on food.Gold colloidal solution with good size distribution(50 nm) is prepared using the standard sodium citrate reduction method,followed by coating a thin layer of SiO2on Au nanoparticle surface.This shell-isolated Au@SiO2 is obtained by the addition of active silica to the gold colloidal solution,with the(3-aminopropyl)trimethoxysilane(APTMS) as the coupling agent at pH 8.5.By regulating the amount of the active silica,the Au@SiO2 with different silica shell thickness is synthesized.Ultraviolet-visible spectroscopy(UV-Vis) and transmission electron microscope(TEM) are employed to characterize the optical property and morphology of the as-synthesized Au@SiO2 nanoparticles.The amount of the active silica added in preparation of the Au@SiO2is optimized through comparing the surface enhanced Raman scattering(SERS) intensity of acid orange Ⅱ,using the synthetic Au@SiO2 structure as the SERS substrate.Under the optimized experimental conditions,acid orange Ⅱ on the Si wafer can be detected at concentrations below 0.17 mg/L.The feasibility of the proposed method for detecting acid orange Ⅱ in real samples is verified by spreading the Au@SiO2 nanoparticles on the surface of the watermelon seeds

  11. Adsorption of toxic mercury(II) by an extracellular biopolymer poly(gamma-glutamic acid).

    Science.gov (United States)

    Inbaraj, B Stephen; Wang, J S; Lu, J F; Siao, F Y; Chen, B H

    2009-01-01

    Adsorption of mercury(II) by an extracellular biopolymer, poly(gamma-glutamic acid) (gamma-PGA), was studied as a function of pH, temperature, agitation time, ionic strength, light and heavy metal ions. An appreciable adsorption occurred at pH>3 and reached a maximum at pH 6. Isotherms were well predicted by Redlich-Peterson model with a dominating Freundlich behavior, implying the heterogeneous nature of mercury(II) adsorption. The adsorption followed an exothermic and spontaneous process with increased orderliness at solid/solution interface. The adsorption was rapid with 90% being attained within 5 min for a 80 mg/L mercury(II) solution, and the kinetic data were precisely described by pseudo second order model. Ionic strength due to added sodium salts reduced the mercury(II) binding with the coordinating ligands following the order: Cl(-) >SO(4)(2-) >NO(3)(-). Both light and heavy metal ions decreased mercury(II) binding by gamma-PGA, with calcium(II) ions showing a more pronounced effect than monovalent sodium and potassium ions, while the interfering heavy metal ions followed the order: Cu(2+) > Cd(2+) > Zn(2+). Distilled water adjusted to pH 2 using hydrochloric acid recovered 98.8% of mercury(II), and gamma-PGA reuse for five cycles of operation showed a loss of only 6.5%. IR spectra of gamma-PGA and Hg(II)-gamma-PGA revealed binding of mercury(II) with carboxylate and amide groups on gamma-PGA.

  12. Association of Cross Linked C-Telopeptide II Collagen and Hyaluronic Acid with Knee Osteoarthritis Severity

    Directory of Open Access Journals (Sweden)

    John Butar Butar

    2013-12-01

    Full Text Available BACKGROUND: This study was carried out to investigate the association of Cross Linked C-Telopeptide Type I & II Collagen (CTX-I and II and hyaluronic acid (HA with knee osteoarthritis (OA severity. METHODS: Sixty menopause women with primary knee OA were enrolled in this study during their visits to the Outpatient Department. Patients with knee pain during weight bearing, active or passive range of motion, or tenderness with Kellgren-Lawrence (KL grade of more than I were included. Patients with injury, inflammatory and metabolic diseases were excluded. Patients were put in a 10-hour fasting prior to withdrawal of morning blood samples for examinations of HA, CTX-I, interleukin 1 beta (IL-1β, and high sensitivity C reactive protein (hs-CRP level. Second void morning urine specimens were taken for CTXII assessment. HA, CTX-I and II levels were measured by enzyme-linked immunosorbent assay. RESULTS: Sixty menopausal female patients were included in this study, 35 with KL grade II, 17 grade III, and 8 grade IV. Means of CTX-II were significantly different between subjects KL grade IV and III (p=0.021. Correlation of KL grade was significant with CTX-II (p=0.001, r=0.412 and HA (p=0.0411, r=0.269. KL grades were not significantly associated with CTX-I (p=0.8364, r=-0.0272; IL-1β (p=0.5773, r=0.0853 and hs-CRP (p=0.2625, r=0.1470. CONCLUSIONS: CTX-II and HA were associated with severity of knee OA, suggesting that CTX-II and HA can be used as marker for knee OA severity. KEYWORDS: CTX-II, hyaluronic acid, otestoarthritis, knee.

  13. Chemodynamics of metal complexation by natural soft colloids: Cu(II) binding by humic acid

    NARCIS (Netherlands)

    Town, R.M.; Duval, J.F.L.; Buffle, J.; Leeuwen, van H.P.

    2012-01-01

    The chemodynamics of Cu(II) complexation by humic acid is interpreted in terms of recently developed theory for permeable charged nanoparticles. Two opposing electric effects are operational with respect to the overall rate of association, namely, (i) the conductive enhancement of the diffusion of

  14. Enantioselective self-assembly of antiferromagnetic hexacopper(II) wheels with chiral amino acid oxamates.

    Science.gov (United States)

    Grancha, Thais; Ferrando-Soria, Jesús; Cano, Joan; Lloret, Francesc; Julve, Miguel; De Munno, Giovanni; Armentano, Donatella; Pardo, Emilio

    2013-07-01

    The Cu(2+)-mediated self-assembly of oxamato-based ligands derived from either the (S)- or (R)-enantiomers of the amino acid valine leads to the formation of two antiferromagnetically coupled homochiral anionic hexacopper(II) wheels in the presence of templating tetramethylammonium countercations.

  15. Integrated iron(II) oxidation and limestone neutralisation of acid mine water

    CSIR Research Space (South Africa)

    Maree, JP

    1999-01-01

    Full Text Available Volumetric iron (II) oxidation rates exceeding 100 g/(l.d) were achieved by dosing powdered limestone to a bio-reactor treating artificial acid mine water. Neutralisation and partial sulphate removal were achieved as well. The rate is highly...

  16. 21 CFR 146.135 - Orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Orange juice. 146.135 Section 146.135 Food and... CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.135 Orange juice. (a) Orange juice is the unfermented juice obtained from mature oranges of the...

  17. Photo-transformation of pedogenic humic acid and consequences for Cd(II), Cu(II) and Pb(II) speciation and bioavailability to green microalga.

    Science.gov (United States)

    Worms, Isabelle A M; Adenmatten, David; Miéville, Pascal; Traber, Jacqueline; Slaveykova, Vera I

    2015-11-01

    Humic substances (HS) play key role in toxic metal binding and protecting aquatic microorganisms from metal-induced stress. Any environmental changes that could alter HS concentration and reactivity can be expected to modify metal complexation and thus affect metal speciation and bioavailability to microalgae. The present study explores the influence of increased solar irradiance on the chemical structures and molecular weight of Elliott soil humic acid (EHA) and the associated consequences for Cd(II), Cu(II) and Pb(II) complexation and intracellular metal content in microalga. The results demonstrate that high radiance doses induce an oxidation of EHA with a formation of low molecular weight acids, an increase of -OH and -COOH group abundance, and a drop in EHA hydrodynamic size and molecular weight. The photo-induced structural changes are accompanied with a release of metal from M-EHA complexes and narrowing their size distribution, which in turn results in an increase of the intracellular Cd, Cu and Pb contents in microalga Chlamydomonas reinhardtii in agreement with the measured free metal ions concentrations.

  18. Mathematical Kinetic Modelling and Representing Design Equation for a Packed Photoreactor with Immobilised TiO2-P25 Nanoparticles on Glass Beads in the Removal of C.I. Acid Orange 7

    Directory of Open Access Journals (Sweden)

    Sheidaei Behnaz

    2015-06-01

    Full Text Available In this work, a design equation was presented for a batch-recirculated photoreactor composed of a packed bed reactor (PBR with immobilised TiO2-P25 nanoparticle thin films on glass beads, and a continuous-flow stirred tank (CFST. The photoreactor was studied in order to remove C.I. Acid Orange 7 (AO7, a monoazo anionic dye from textile industry, by means of UV/TiO2 process. The effect of different operational parameters such as the initial concentration of contaminant, the volume of solution in CFST, the volumetric flow rate of liquid, and the power of light source in the removal efficiency were examined. A rate equation for the removal of AO7 is obtained by mathematical kinetic modelling. The results of reaction kinetic analysis indicate the conformity of removal kinetics with Langmuir-Hinshelwood model (kL-H = 0.74 mg L-1 min-1, Kads = 0.081 mg-1 L. The represented design equation obtained from mathematical kinetic modelling can properly predict the removal rate constant of the contaminant under different operational conditions (R2 = 0.963. Thus the calculated and experimental results are in good agreement with each other.

  19. Adsorptive removal of Methylene blue and Methyl orange from aqueous media by carboxylated diaminoethane sporopollenin: On the usability of an aminocarboxilic acid functionality-bearing solid-stationary phase in column techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ayar, Ahmet [Nigde University, Faculty of Science and Art, Department of Chemistry, 51100 Nigde (Turkey); Gezici, Orhan [Nigde University, Faculty of Science and Art, Department of Chemistry, 51100 Nigde (Turkey) and Selcuk University, Institution of Natural and Applied Sciences, Konya (Turkey)]. E-mail: ogezici@nigde.edu.tr; Kuecuekosmanoglu, Muhittin [Nigde University, Faculty of Science and Art, Department of Chemistry, 51100 Nigde (Turkey)

    2007-07-19

    The adsorption phenomena of Methylene blue (MB) and Methyl orange (MO) on a carboxylated diaminoethane sporopollenin (CDAE-S) solid phase were investigated in a column arrangement by using breakthrough technique. The adsorption phenomena were evaluated using some common adsorption isotherm models and Scatchard plot analysis, and obtained results were interpreted for evaluating the usability of CDAE-S for removal, recovery and preconcentration of the studied dyes both at the laboratory and industrial scales. On the basis of Scatchard plot analysis, the interaction types between the CDAE-S and the studied dyes were criticized in terms of affinity phenomena. Thus, the usability of a biomacromolecule-derived material, CDAE-S, as a cheap, environmentally-friendly and effective solid-stationary phase exhibiting both cation-exchange and anion-exchange characteristics at the same time, is discussed through the present study. Besides, from the obtained results, the protonated CDAE-S, which functionally resembles an amino acid structure, are presented as a two-in-one solid-stationary phase, and its adaptability to common processes performed under column conditions is also drawn in detail.

  20. Determination of Precipitation Limit of Zn(II Ion with (2S-2-Aminobutanedioic Acid

    Directory of Open Access Journals (Sweden)

    Fatmir Faiku

    2009-01-01

    Full Text Available Problem statement: In this study we examined the precipitation of Zn(II ion in water solutions of ZnSO4.7H2O (1.10-2 and 5.10-3 mol L-1 with (2S-2-aminobutanedioic acid (1.10--1.10-3 mol L-1 in constant ionic strength of 0.6 mol L-1 NaCl. We have determined the concentration region where we have found the clear solution and solid phase. The solid phase is analyzed by IR spectroscopy. Approach: From precipitation diagrams of zinc with (2S-2-aminobutanedioic acid in ionic force 0.6 mol L-1 NaCl, we have found that during decreasing the concentration (2S-2-aminobutanedioic acid in case of constant concentration of Zn(II the limit of precipitation is shifted to lower values of pH. Results: Also from precipitation diagrams we can see that when the concentration of zinc increases, in case of constant concentration of (2S-2-aminobutanedioic acid the limit of precipitation will shift at lower values of pH. Conclusion: From the IR spectroscopic analysis we can conclude that Zn (II ion has reacted with (2S-2-aminobutanedioic acid.

  1. Adsorption of Pb(II Ions on Sulfuric Acid Treated Leucaena leucocephala Leaf Powder

    Directory of Open Access Journals (Sweden)

    Mansur Noor Fhadzilah

    2015-01-01

    Full Text Available Sulfuric acid treated Petai belalang (Leucaena leucocephala leaf powder (SLLP was used as an adsorbent for Pb(II ions removal. The experimental adsorption parameters investigated include pH, dosage and initial Pb(II concentration. Pb(II removal was more favored at a higher adsorbent dosage, pH and temperature. Adsorption kinetics conformed to the pseudo-second order model while Langmuir isotherm model recorded the value of maximum adsorption capacity (qmax of 222 mg/g. The major functional groups involved in the adsorption process were identified as hydroxyl, amino and ether as revealed by the FTIR analysis. The prepared adsorbent demonstrated a potential application for efficient removal of Pb(II ions from industrial wastewater.

  2. Photoinduced electron transfer reactions of ruthenium(II)-complexes containing amino acid with quinones.

    Science.gov (United States)

    Eswaran, Rajkumar; Kalayar, Swarnalatha; Paulpandian, Muthu Mareeswaran; Seenivasan, Rajagopal

    2014-05-01

    With the aim of mimicking, at basic level the photoinduced electron transfer process in the reaction center of photosystem II, ruthenium(II)-polypyridyl complexes, carrying amino acids were synthesized and studied their photoinduced electron transfer reactions with quinones by steady state and time resolved measurements. The reaction of quinones with excited state of ruthenium(II)-complexes, I-V in acetonitrile has been studied by luminescence quenching technique and the rate constant, k(q), values are close to the diffusion controlled rate. The detection of the semiquinone anion radical in this system using time-resolved transient absorption spectroscopy confirms the electron transfer nature of the reaction. The semiclassical theory of electron transfer has been successfully applied to the photoluminescence quenching of Ru(II)-complexes with quinones.

  3. Spectrophotometric determination of bismuth with semi-xylenol orange and its application in metal analysis.

    Science.gov (United States)

    Nan, Z; Ren-Qing, Y; Xu-Zhang, Y; Zhi-Ren, L

    1989-07-01

    Semi-Xylenol Orange forms a 2 : 1 chelate with bismuth(III), which has a logarithmic value of 3.08 for its conditional formation constant and a molar absorptivity of 4.2 x 10(4) l.mole(-1).cm(-1). Beer's law is obeyed at 540 nm over the range 10-30 mug of Bi(III), with a standard deviation of 1.1 mug (n = 18). Lactic acid is used as an auxiliary complexing agent to prevent olation and oxolation. Interference from up to 1.3 mg of copper can be eliminated by the combined use of masking Cu(II) with thiourea, ascorbic acid and thiosemicarbazide and "post-masking" Bi(III) with sodium chloride. The proposed method has been successfully applied to the direct determination of 0.002% of Bi in lead metal, with a coefficient of variation varying from 3.7 to 6.9%.

  4. Salvianolic Acid B Attenuates Rat Hepatic Fibrosis via Downregulating Angiotensin II Signaling

    Science.gov (United States)

    Li, Shu; Wang, Lina; Yan, Xiuchuan; Wang, Qinglan; Tao, Yanyan; Li, Junxia; Peng, Yuan; Liu, Ping; Liu, Chenghai

    2012-01-01

    The renin-angiotensin system (RAS) plays an important role in hepatic fibrosis. Salvianolic acid B (Sal B), one of the water-soluble components from Radix Salviae miltiorrhizae, has been used to treat hepatic fibrosis, but it is still not clear whether the effect of Sal B is related to angiotensin II (Ang II) signaling pathway. In the present study, we studied Sal B effect on rat liver fibrosis and Ang-II related signaling mediators in dimethylnitrosamine-(DMN-) induced rat fibrotic model in vivo and Ang-II stimulated hepatic stellate cells (HSCs) in vitro, with perindopril or losartan as control drug, respectively. The results showed that Sal B and perindopril inhibited rat hepatic fibrosis and reduced expression of Ang II receptor type 1 (AT1R) and ERK activation in fibrotic liver. Sal B and losartan also inhibited Ang II-stimulated HSC activation including cell proliferation and expression of type I collagen I (Col-I) and α-smooth muscle actin (α-SMA) production in vitro, reduced the gene expression of transforming growth factor beta (TGF-β), and downregulated AT1R expression and ERK and c-Jun phosphorylation. In conclusion, our results indicate that Sal B may exert an antihepatic fibrosis effect via downregulating Ang II signaling in HSC activation. PMID:23243430

  5. Salvianolic Acid B Attenuates Rat Hepatic Fibrosis via Downregulating Angiotensin II Signaling

    Directory of Open Access Journals (Sweden)

    Shu Li

    2012-01-01

    Full Text Available The renin-angiotensin system (RAS plays an important role in hepatic fibrosis. Salvianolic acid B (Sal B, one of the water-soluble components from Radix Salviae miltiorrhizae, has been used to treat hepatic fibrosis, but it is still not clear whether the effect of Sal B is related to angiotensin II (Ang II signaling pathway. In the present study, we studied Sal B effect on rat liver fibrosis and Ang-II related signaling mediators in dimethylnitrosamine-(DMN- induced rat fibrotic model in vivo and Ang-II stimulated hepatic stellate cells (HSCs in vitro, with perindopril or losartan as control drug, respectively. The results showed that Sal B and perindopril inhibited rat hepatic fibrosis and reduced expression of Ang II receptor type 1 (AT1R and ERK activation in fibrotic liver. Sal B and losartan also inhibited Ang II-stimulated HSC activation including cell proliferation and expression of type I collagen I (Col-I and α-smooth muscle actin (α-SMA production in vitro, reduced the gene expression of transforming growth factor beta (TGF-β, and downregulated AT1R expression and ERK and c-Jun phosphorylation. In conclusion, our results indicate that Sal B may exert an antihepatic fibrosis effect via downregulating Ang II signaling in HSC activation.

  6. 高效液相色谱法测定武夷橙中的有机酸%Determination of Organic Acids in Wuyi Orange by High Performance Liquid Chromatography

    Institute of Scientific and Technical Information of China (English)

    许原

    2012-01-01

    利用反相高效液相色谱法研究了武夷橙中7种有机酸的分离测定条件。采用C18为分析柱,以2.5%磷酸二氢铵缓冲溶液(PH=2.5)为流动相,流速为1mL/min,紫外检测波长在210nm处可以很好的分离测定有机酸。结果表明峰面积与相应的质量浓度有良好的线性关系,其r大于等于0.9990,平均回收率为98%~110%,该方法具有测定结果准确可靠,重现好等特点。%The condition of separation and detection of seven organic acids in Wuyi Orange by reversed-phase high performance liquid chromatography were studied .The organic acids can be separated and determined better in the conditions of 2.5% ammonium dihydrogen phosphate buffer solution(pH=2.5) as mobile phase, at a flow rate of 1mL/min and UV detection 210nm on a C18 column. The results showed that the area and the content were in a well linear correlation(r≧0.9990), the average recovery was 98%~110%. This method also had the simple, well accuracy.

  7. [Influence of inorganic ions and humic acid on the removal of Pb(II) and Hg(II) in water by zero-valent iron].

    Science.gov (United States)

    Shi, Qiu-Ling; Zhou, Xin; Zhang, Jin-Zhong; Qiu, Xin-Kai

    2014-08-01

    The effects of Ca2+, Cl- and humic acid (HA) on the removal rates of Pb(II) and Hg(II) in water by zero-valent (ZVI) and the kinetic characteristics were studied, and the removal mechanism of Pb(II) and Hg(II) by ZVI were preliminarily investigated using X-ray diffraction (XRD). The results indicated that the removal mechanism of Pb(II) might mainly be attributed to the adsorption and co-precipitation of ZVI, while that of Hg(II) might mainly be attributed to the oxidation-reduction of ZVI. With the increase of Ca2+ concentration, the removal rates of Hg(II) and Pb(II) showed the trends of gradual increase and slight decrease, respectively. The Hg(II) removal increased with increasing Cl- concentration, whereas no obvious increase in Pb(II) removal was observed. The removal rates of Hg(II) and Pb(II) showed the trends of slow increase and slow decrease with increasing HA concentration, respectively. When Ca2+, Cl- and HA coexisted, the removal rates of Hg(II) and Pb(II) reached 99.71% and 97.95%, respectively. The removal processes of Pb(II) and Hg(II) could be described by pseudo first-order reaction kinetic equations when Ca2+, Cl- and HA existed alone and in combination. The removal rate constant of Pb(II) was the maxinum (0.024 0 min(-1)) when 5 mg x L(-1) HA existed alone, whereas that of Hg(II) was the maximum (0.0169 min(-1)) when 0.80 mmol x L(-1) Ca2+ existed alone.

  8. Monitoring of total type ii pyrethroid pesticides in citrus oils and water by converting to a common product 3-phenoxybenzoic acid.

    Science.gov (United States)

    McCoy, Mark R; Yang, Zheng; Fu, Xun; Ahn, Ki Chang; Gee, Shirley J; Bom, David C; Zhong, Ping; Chang, Dan; Hammock, Bruce D

    2012-05-23

    Pyrethroids are a class of insecticides that are becoming increasingly popular in agricultural and home use applications. Sensitive assays for pyrethroid insecticides in complex matrices are difficult with both instrumental and immunochemical methods. Environmental analysis of the pyrethroids by immunoassay requires either knowing which pyrethroids contaminate the source or the use of nonspecific antibodies with cross-reactivities to a class of compounds. We describe an alternative method that converts the type II pyrethroids to a common chemical product, 3-phenoxybenzoic acid (3-PBA), prior to analysis. This method is much more sensitive than detecting the parent compound, and it is much easier to detect a single compound rather than an entire class of compounds. This is useful in screening for pyrethroids as a class or in situations where a single type of pyrethroid is used. We demonstrated this technique in both citrus oils and environmental water samples with conversion rates of the pyrethroid to 3-PBA that range from 45 to 75% and methods that require no extraction steps for either the immunoassay or the liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques. Limits of detection for this technique applied to orange oil are 5 nM, 2 μM, and 0.8 μM when detected by LC-MS/MS, gas chromatography-mass spectrometry, and immunoassay, respectively. The limit of detection for pyrethroids in water when detected by immunoassay was 2 nM.

  9. Metal-Based Antibacterial and Antifungal Agents: Synthesis, Characterization, and In Vitro Biological Evaluation of Co(II, Cu(II, Ni(II, and Zn(II Complexes with Amino Acid-Derived Compounds

    Directory of Open Access Journals (Sweden)

    Zahid H. Chohan

    2006-01-01

    Full Text Available A series of antibacterial and antifungal amino acid-derived compounds and their cobalt(II, copper(II, nickel(II, and zinc(II metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments, and IR, and electronic spectral measurements. Ligands (L1–(L5 were derived by condensation of β-diketones with glycine, phenylalanine, valine, and histidine and act as bidentate towards metal ions (cobalt, copper, nickel, and zinc via the azomethine-N and deprotonated-O of the respective amino acid. The stoichiometric reaction between the metal(II ion and synthesized ligands in molar ratio of M: L (1: 1 resulted in the formation of the metal complexes of type [M(L(H2O4]Cl (where M = Co(II, Cu(II, and Zn(II and of M: L (1: 2 of type [M(L2(H2O2] (where M = Co(II, Cu(II, Ni(II, and Zn(II. The magnetic moment data suggested for the complexes to have an octahedral geometry around the central metal atom. The electronic spectral data also supported the same octahedral geometry of the complexes. Elemental analyses and NMR spectral data of the ligands and their metal(II complexes agree with their proposed structures. The synthesized ligands, along with their metal(II complexes, were screened for their in vitro antibacterial activity against four Gram-negative (Escherichia coli, Shigella flexeneri, Pseudomonas aeruginosa, and Salmonella typhi and two Gram-positive (Bacillus subtilis and Staphylococcus aureus bacterial strains and for in vitro antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani, and Candida glaberata. The results of these studies show the metal(II complexes to be more antibacterial/antifungal against one or more species as compared to the uncomplexed ligands. The brine shrimp bioassay was also carried out to study their in vitro cytotoxic properties. Five compounds, (3, (7, (10, (11, and (22, displayed potent cytotoxic

  10. 19-Hydroxyeicosatetraenoic acid and isoniazid protect against angiotensin II-induced cardiac hypertrophy.

    Science.gov (United States)

    Elkhatali, Samya; El-Sherbeni, Ahmed A; Elshenawy, Osama H; Abdelhamid, Ghada; El-Kadi, Ayman O S

    2015-12-15

    We have recently demonstrated that 19-hydroxyeicosatetraenoic acid (19-HETE) is the major subterminal-HETE formed in the heart tissue, and its formation was decreased during cardiac hypertrophy. In the current study, we examined whether 19-HETE confers cardioprotection against angiotensin II (Ang II)-induced cardiac hypertrophy. The effect of Ang II, with and without 19-HETE (20 μM), on the development of cellular hypertrophy in cardiomyocyte RL-14 cells was assessed by real-time PCR. Also, cardiac hypertrophy was induced in Sprague-Dawley rats by Ang II, and the effect of increasing 19-HETE by isoniazid (INH; 200mg/kg/day) was assessed by heart weight and echocardiography. Also, alterations in cardiac cytochrome P450 (CYP) and their associated arachidonic acid (AA) metabolites were determined by real-time PCR, Western blotting and liquid-chromatography-mass-spectrometry. Our results demonstrated that 19-HETE conferred a cardioprotective effect against Ang II-induced cellular hypertrophy in vitro, as indicated by the significant reduction in β/α-myosin heavy chain ratio. In vivo, INH improved heart dimensions, and reversed the increase in heart weight to tibia length ratio caused by Ang II. We found a significant increase in cardiac 19-HETE, as well as a significant reduction in AA and its metabolite, 20-HETE. In conclusion, 19-HETE, incubated with cardiomyocytes in vitro or induced in the heart by INH in vivo, provides cardioprotection against Ang II-induced hypertrophy. This further confirms the role of CYP, and their associated AA metabolites in the development of cardiac hypertrophy. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. 2-Hexadecynoic Acid Inhibits Plasmodial FAS-II Enzymes and Arrest Erythrocytic and Liver Stage Plasmodium Infections

    OpenAIRE

    Tasdemir, Deniz; Sanabria, David; Lauinger, Ina L.; Tarun, Alice; Herman, Rob; Perozzo, Remo; Zloh, Mire; Kappe, Stefan H.; Brun, Reto; Carballeira, Néstor M.

    2010-01-01

    Acetylenic fatty acids are known to display several biological activities, but their antimalarial activity has remained unexplored. In this study, we synthesized the 2-, 5-, 6-, and 9-hexadecynoic acids (HDAs) and evaluated their in vitro activity against erythrocytic (blood) stages of Plasmodium falciparum and liver stages of P. yoelii infections. Since the type II fatty acid biosynthesis pathway (PfFAS-II) has recently been shown to be indispensable for liver stage malaria parasites, the in...

  12. Physics of soft hyaluronic acid-collagen type II double network gels

    Science.gov (United States)

    Morozova, Svetlana; Muthukumar, Murugappan

    2015-03-01

    Many biological hydrogels are made up of multiple interpenetrating, charged components. We study the swelling, elastic diffusion, mechanical, and optical behaviors of 100 mol% ionizable hyaluronic acid (HA) and collagen type II fiber networks. Dilute, 0.05-0.5 wt% hyaluronic acid networks are extremely sensitive to solution salt concentration, but are stable at pH above 2. When swelled in 0.1M NaCl, single-network hyaluronic acid gels follow scaling laws relevant to high salt semidilute solutions; the elastic shear modulus G' and diffusion constant D scale with the volume fraction ϕ as G' ~ϕ 9 / 4 and D ~ϕ 3 / 4 , respectively. With the addition of a collagen fiber network, we find that the hyaluronic acid network swells to suspend the rigid collagen fibers, providing extra strength to the hydrogel. Results on swelling equilibria, elasticity, and collective diffusion on these double network hydrogels will be presented.

  13. New copper(II) complexes with dopamine hydrochloride and vanillymandelic acid: Spectroscopic and thermal characterization

    Science.gov (United States)

    Mohamed, Gehad G.; Nour El-Dien, F. A.; El-Nahas, R. G.

    2011-10-01

    The dopamine derivatives participate in the regulation of wide variety of physiological functions in the human body and in medication life. Increase and/or decrease in the concentration of dopamine in human body reflect an indication for diseases such as Schizophrenia and/or Parkinson diseases. The Cu(II) chelates with coupled products of dopamine hydrochloride (DO.HCl) and vanillymandelic acid (VMA) with 4-aminoantipyrine (4-AAP) are prepared and characterized. Different physico-chemical techniques namely IR, magnetic and UV-vis spectra are used to investigate the structure of these chelates. Cu(II) forms 1:1 (Cu:DO) and 1:2 (Cu:VMA) chelates. DO behave as a uninegative tridentate ligand in binding to the Cu(II) ion while VMA behaves as a uninegative bidentate ligand. IR spectra show that the DO is coordinated to the Cu(II) ion in a tridentate manner with ONO donor sites of the phenolic- OH, -NH and carbonyl- O, while VMA is coordinated with OO donor sites of the phenolic- OH and -NH. Magnetic moment measurements reveal the presence of Cu(II) chelates in octahedral and square planar geometries with DO and VMA, respectively. The thermal decomposition of Cu(II) complexes is studied using thermogravimetric (TG) and differential thermal analysis (DTA) techniques. The activation thermodynamic parameters, such as, energy of activation, enthalpy, entropy and free energy change of the complexes are evaluated and the relative thermal stability of the complexes are discussed.

  14. Metabolism: Part II. The Tricarboxylic Acid (TCA), Citric Acid, or Krebs Cycle.

    Science.gov (United States)

    Bodner, George M.

    1986-01-01

    Differentiates the tricarboxylic acid (TCA) cycle (or Krebs cycle) from glycolysis, and describes the bridge between the two as being the conversion of pyruvate into acetyl coenzyme A. Discusses the eight steps in the TCA cycle, the results of isotopic labeling experiments, and the net effects of the TCA cycle. (TW)

  15. Metabolism: Part II. The Tricarboxylic Acid (TCA), Citric Acid, or Krebs Cycle.

    Science.gov (United States)

    Bodner, George M.

    1986-01-01

    Differentiates the tricarboxylic acid (TCA) cycle (or Krebs cycle) from glycolysis, and describes the bridge between the two as being the conversion of pyruvate into acetyl coenzyme A. Discusses the eight steps in the TCA cycle, the results of isotopic labeling experiments, and the net effects of the TCA cycle. (TW)

  16. Cytotoxicity of copper(II) complexes of N-salicylidene-L-glutamate: modulation by ascorbic acid.

    Science.gov (United States)

    Paulikova, H; Kadlecikova, E; Suchanova, M; Valkova, Z; Rauko, P; Hudecova, D; Valent, A

    2008-01-01

    Cytotoxic/cytostatic activity of N-salicylidene-L-glutamato diaqua copper(II) complex (CuC) against mice leukemia cells L1210 has been estimated and their bioactivity was enhanced by addition of ascorbic acid. The Cu-complex with isoquinoline ligand (IQ-CuC) had stronger cytostatic effect (IC50 =15.6 microM) than parental complex (CuC) and its cytotoxicity several times increased in the presence of 0.1 mM ascorbic acid (IC50 =1.0 microM). The cytotoxicity has been caused by oxidative stress, enhanced creation of TBARS has been confirmed, and formation of 2',7'-dichlorofluorescein from 2',7'- dichlorodihydrofluorescein has been observed, also. Some hallmarks of apoptotic/necrotic death of L1210 cells have been observed by fluorescent microscopy after dyeing of cell with propidium iodide and Hoechst 33342. In addition, it was confirmed that both complexes in the presence of ascorbic acid cleavaged of pDNA. Although these copper complexes were initially prepared as substances with antioxidant properties we have showed that combined treatment of L1210 cells with IQCuC and ascorbic acid induced strong oxidative stress and death of cells. Our results confirmed that physiological concentration of ascorbic acid increases the cytostatic/cytotoxic efficiency of N-salicylidene-L-glutamato diaqua copper(II) complexes.

  17. Trans-dichlorodiammineplatinum(II). Acid hydrolysis and the isotopic exchange of the chloride ligands

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Jr., D. S.; Adams, R. J.

    1961-12-31

    The isotopic exchange of chloride ligands of trans-dichlorodiammineplatinum(II) was explored. The rates of isotopic exchange were measured with Cl/sup 36/tracer only in solutions which were at chemical equilibrium. The exchange rate was found to contain a second-order (chloride-dependent) term, in addition to the expected acid hydrolysis term. At Cl/sup -/= 0.l M, the two processes contribute about equally to the exchange. It was also found that k/sub 1/ for t-Pt(NH/sub 3/)sub 2/Cl/sub 2/is larger than for any of the other chloroamine complexes. A summary of the acid hydrolysis equilibrium quotients and rate constants for platinum (II) complexes and other data are tabulated. (P.C.H.)

  18. Characterization of hydroxybenzoic acid chelating resins: equilibrium, kinetics, and isotherm profiles for Cd(II and Pb(II uptake

    Directory of Open Access Journals (Sweden)

    BHAVNA A. SHAH

    2011-06-01

    Full Text Available Chelating ion-exchange resins were synthesized by polycondensation of ortho/para hydroxybenzoic acid with resorcinol/catechol employing formaldehyde as cross-linking agent at 80±5 °C in DMF. The resins were characterized by FTIR and XRD. The uptake behaviour of synthesized resins for Cd(II and Pb(II ions have been studied depending on contact time, pH, metal ion concentration and temperature. The sorption data obtained at optimized conditions were analyzed by the Langmuir and Freundlich isotherms. Experimental data of all metal–resin system were best represented by the Freundlich isotherm. The maximum obtained sorption capacity for cadmium was 69.53 mg g-1 and 169.32 mg g-1 for Lead. The adsorption process follows first order kinetics and the specific rate constant Kr was obtained by the application of the Lagergan equation. Thermodynamic parameters ∆Gads, ∆Sads and ∆Hads were calculated for the metal–resin systems. The external diffusion rate constant (KS and the intra-particle diffusion rate constant (Kid were calculated by the Spahn–Schlunder and Weber–Morris models, respectively. The sorption process was found to follow an intra-particle diffusion phenomenon.

  19. Antibacterial activity of Pd(II) complexes with salicylaldehyde-amino acids Schiff bases ligands.

    Science.gov (United States)

    Rîmbu, Cristina; Danac, Ramona; Pui, Aurel

    2014-01-01

    Palladium(II) complexes with Schiff bases ligands derived from salicylaldehyde and amino acids (Ala, Gly, Met, Ser, Val) have been synthesized and characterized by Fourier transform (FT)-IR, UV-Vis and (1)H-NMR spectroscopy. The electrospray mass spectrometry (ES-MS) spectrometry confirms the formation of palladium(II) complexes in 1/2 (M/L) molar ratio. All the Pd(II) complexes 1, [Pd(SalAla)2]Cl2; 2, [Pd(SalGly)2]Cl2; 3, [Pd(SalMet)2]Cl2; 4, [Pd(SalSer)2]Cl2; 5, [Pd(SalVal)2]Cl2; have shown antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli.

  20. Cd(II) Sorption on Montmorillonite-Humic acid-Bacteria Composites

    OpenAIRE

    Du, H.; Chen, W.; Cai, P.; Rong, X; Dai, K; Peacock, CL; Huang, Q.

    2016-01-01

    Soil components (e.g., clays, bacteria and humic substances) are known to produce mineral-organic composites in natural systems. Herein, batch sorption isotherms, isothermal titration calorimetry (ITC), and Cd K-edge EXAFS spectroscopy were applied to investigate the binding characteristics of Cd on montmorillonite(Mont)-humic acid(HA)-bacteria composites. Additive sorption and non-additive Cd(II) sorption behaviour is observed for the binary Mont-bacteria and ternary Mont-HA-bacteria composi...

  1. Hydrolytic activity of -alkoxide/acetato-bridged binuclear Cu(II) complexes towards carboxylic acid ester

    Indian Academy of Sciences (India)

    Weidong Jiang; Bin Xu; Zhen Xiang; Shengtian Huang; Fuan Liu; Ying Wang

    2013-09-01

    Two -alkoxide/acetate-bridged small molecule binuclear copper(II) complexes were synthesized, and used to promote the hydrolysis of a classic carboxylic acid ester, -nitrophenyl picolinate (PNPP). Both binuclear complexes exhibited good hydrolytic reactivity, giving rise to . 15547- and 17462-fold acceleration over background value for PNPP hydrolysis at neutral conditions, respectively. For comparing, activities of the other two mononuclear analogues were evaluated, revealing that binuclear complexes show approximately 150- and 171-fold kinetic advantage over their mononuclear analogues.

  2. Removal of Methyl Orange from Aqueous Solution by Nitric Acid-Modified Titanium Ore%硝酸掺杂钛精矿吸附去除甲基橙

    Institute of Scientific and Technical Information of China (English)

    雷雪飞; 薛向欣; 杨合

    2012-01-01

    Nitric acid-modified titanium ore (NATO) sorbents were prepared by high energy ball milling process. The adsorption properties of NATO sorbents were evaluated by the decoloration efficiency of methyl orange (MO) under dark-state absorption. In the adsorption stage, L9(34) orthogonal experiments of different factors, for example, doping ratio, calcination temperature, soaking time and heating rate were performed. Based on the orthogonal experiments, the optimal operating parameters, 2.0wt % nitric acid, 300 ℃ calcination temperature, 3 h soaking time, and 10 ℃/min heating rate, are obtained. In this optimal condition, the decoloration efficiency of MO reaches 96.8 %, which is significantly better than the undoped samples. Thus, it is feasible to treat dye wastewater by these NATO sorbents.%采用高能球磨法制备了一系列硝酸掺杂的钛精矿(nitric acid-modified titanium ore,NATO)吸附材料,采用正交表L9(34)安排实验,以甲基橙(MO)溶液的脱色率作为衡量吸附剂优劣的重要判据.以硝酸掺杂比例、煅烧温度、保温时间、升温速率为因素进行正交试验,基于降低能耗和成本的考虑和综合分析的基础上,得到制备NATO吸附剂的最优工艺条件:硝酸掺杂比例为2.0%,煅烧温度为300℃,保温时间为3 h,升温速率为10℃/min.在较优工艺条件下制备的NATO吸附剂对甲基橙的脱色率达到96.8%,明显优于未掺杂样品,且沉降性能较好,易于分离,是一类有应用前景的吸附材料.

  3. Preparation, characterization and environmental applications of Sr1 - x (La,Bi) x TiO3 perovskites immobilized on Ni-foam: photodegradation of the Acid Orange 7.

    Science.gov (United States)

    Nunes, M J; Lopes, A; Pacheco, M J; Ciríaco, L

    2016-08-13

    The Sr1 - x La x TiO3 (0 ≤ x ≤ 0.4) and Sr1 - x Bi x TiO3 (0 ≤ x ≤ 0.3) perovskites were prepared via solid state reaction by partially replacing the Sr(2+) ions in the SrTiO3 structure by La(3+) or Bi(3+) ions, characterized and utilized as photocatalysts immobilized in Ni-foam substrate in the degradation of the azo dye Acid Orange 7 (AO7). For both perovskite families, the XRD data reveal the existence of a predominant well-crystallized phase, belonging to a cubic perovskite in a Pm3m space group, with the presence of other minority phases. The characteristic dimension and the volume of the cell decrease with the introduction in the SrTiO3 lattice of the La(3+) or Bi(3+) ions. The grain size of the Sr1 - x La x TiO3 samples is around 100 nm and slightly lower for the Sr1 - x Bi x TiO3 samples. Regarding the utilization of the prepared perovskite powders deposited over the Ni-foam substrates as catalysts in the photodegradation of AO7 solutions, the results show an improvement in the performance of the films of the substituted perovskite when compared to the SrTiO3 perovskite, being the best results obtained with Sr0.9Bi0.1TiO3.

  4. Simultaneous amperometric detection of ascorbic acid and antioxidant capacity in orange, blueberry and kiwi juice, by a telemetric system coupled with a fullerene- or nanotubes-modified ascorbate subtractive biosensor.

    Science.gov (United States)

    Barberis, Antonio; Spissu, Ylenia; Fadda, Angela; Azara, Emanuela; Bazzu, Gianfranco; Marceddu, Salvatore; Angioni, Alberto; Sanna, Daniele; Schirra, Mario; Serra, Pier Andrea

    2015-05-15

    Four fullerenes- or nanotubes-modified graphite sensor-biosensor systems (SBs), coupled with a dual-channel telemetric device, based on an ascorbate oxidase (AOx) biosensor, were developed for on line simultaneous amperometric detection of ascorbic acid (AA) and antioxidant capacity in blueberry, kiwi and orange juice. Fullerene C60 (FC60), fullerene C70 (FC70), single-walled carbon nanotubes (SWCN) and multi-walled carbon nanotubes (MWCN) increased the sensitivity of graphite toward AA and phenols 1.2, 1.5, 5.1 and 5.1 times respectively. Fullerenes combined with AOx improved the selectivity toward AA more than nanotubes, being able to hold a higher number of AOx molecules on the biosensor surface. The SBs work at an applied potential of +500 mV, in a concentration range between the LOD and 20 μM, with a response time of two minutes. The LOD is 0.10, 0.13, 0.20 and 0.22 μM for SBs modified with FC60, FC70, SWCN and MWCN respectively. Biosensors register lower AA currents than the sensors due to the enzyme capability to oxidize AA before it reaches the transductor surface. Phenols currents registered by sensors and biosensors did not differ. Based on the difference between sensor and biosensor recorded currents a AA selectivity index was developed as an indicator of specificity toward AA and of the capacity to distinguish between AA and phenols contribution to the antioxidant capacity. This value is almost zero for fullerene-modified SBs, 0.13 and 0.22 for SWCN- and MWCN-modified SBs respectively. The results of juices analysis performed with SBs were in accordance with reference methods.

  5. A method for the determination of ascorbic acid using the iron(II)-pyridine-dimethylglyoxime complex

    Energy Technology Data Exchange (ETDEWEB)

    Arya, S. P.; Mahajan, M. [Haryana, Kurukshetra Univ. (India). Dept. of Chemistry

    1998-05-01

    A simple and rapid spectrophotometric method for the determination of ascorbic acid is proposed. Ascorbic acid reduces iron (III) to iron (II) which forms a red colored complex with dimethylglyoxime in the presence of pyridine. The absorbance of the resulting solution is measured at 514 nm and a linear relationship between absorbance and concentration of ascorbic acid is observed up to 14 {mu}g ml{sup -1}. Studies on the interference of substances usually associated with ascorbic acid have been carried out and the applicability of the method has been tested by analysing pharmaceutical preparations of vitamin C. [Italiano] Si propone un rapido e semplice metodo spettrofotometrico per la determinazione dell`acido ascorbico. L`acido ascorbico riduce il ferro(III) a ferro(II) che forma con la dimetilgliossima, in presenza di piridina, un complesso colorato in rosso. L`assorbanza della soluzione risultante e` misurata a 514 nm e si ottiene una relazione lineare tra assorbanza e concentrazione dell`acido ascorbico fino a 14 {mu}g ml{sup -1}. Si sono condotti studi sugli interferenti usualmente associati all`acido ascorbico ed e` stata valutata l`applicabilita` del metodo all`analisi di preparati farmaceutici di vitamina C.

  6. Intermolecular DNA ligation activity of eukaryotic toposiomerase II: Potential roles in nucleic acid recombination

    Energy Technology Data Exchange (ETDEWEB)

    Gale, K.C.R.

    1992-01-01

    Single-stranded [phi]X174 (+) strand DNA was used as a model substrate for topoisomerase II to determine whether double-stranded DNA cleavage observed in vitro reflects the in vivo intermediate in the enzyme's catalytic cycle and to investigate potential mechanisms for topoisomerase II-mediated DNA recombination. As found previously for topoisomerase II-mediated cleavage of double-stranded DNA, the enzyme was covalently linked to the 5[prime]-termini of cleaved [phi]X174 molecules. Optimal reaction conditions were similar for the two substrates. In contrast to results with double-stranded molecules, single-stranded DNA cleavage increased with time, was not reversible, and did not require the presence of SDS. Cleavage products generated in the absence of protein denaturant contained free 3[prime]-OH DNA termini. These results strongly suggest that the covalent topoisomerase II-cleaved DNA complex observed in vitro is the active intermediate in the enzyme's catalytic code. Topoisomerase II is capable of joining cleaved [phi]X174 (+) strand DNA to duplex oligonucleotide acceptor molecules by an intermolecular ligation reaction. Intermolecular DNA ligation proceeded in a time and oligonucleotide concentration dependent fashion. The covalent linkage is between the 5[prime]-phosphate of [phi]X174 (+) strand DNA and the 3[prime]-OH of oligonucleotide acceptor molecules. The reaction was dependent on the presence of a divalent cation, was inhibited by salt, and was not affected by the presence of ATP. The enzyme was capable of ligating [phi]X174 (+) strand DNA to double-stranded oligonucleotides that contained 5[prime]-overhang, 3[prime]-overhang, or blunt ends. Single-stranded, nicked, or gapped oligonucleotides could also be used as acceptor molecules. These results demonstrate that the type II enzyme has an intrinsic ability to mediate illegitimate DNA recombination in vitro and suggests possible roles for topoisomerase II in nucleic acid recombination in vivo.

  7. Solubility of xenon in amino-acid solutions. II. Nine less-soluble amino acids

    Science.gov (United States)

    Kennan, Richard P.; Himm, Jeffrey F.; Pollack, Gerald L.

    1988-05-01

    Ostwald solubility (L) of xenon gas, as the radioisotope 133Xe, has been measured as a function of solute concentration, at 25.0 °C, in aqueous solutions of nine amino acids. The amino-acid concentrations investigated covered much of their solubility ranges in water, viz., asparagine monohydrate (0-0.19 M), cysteine (0-1.16 M), glutamine (0-0.22 M), histidine (0-0.26 M), isoleucine (0-0.19 M), methionine (0-0.22 M), serine (0-0.38 M), threonine (0-1.4 M), and valine (0-0.34 M). We have previously reported solubility results for aqueous solutions of six other, generally more soluble, amino acids (alanine, arginine, glycine, hydroxyproline, lysine, and proline), of sucrose and sodium chloride. In general, L decreases approximately linearly with increasing solute concentration in these solutions. If we postulate that the observed decreases in gas solubility are due to hydration, the results under some assumptions can be used to calculate hydration numbers (H), i.e., the number of H2O molecules associated with each amino-acid solute molecule. The average values of hydration number (H¯) obtained at 25.0 °C are 15.3±1.5 for asparagine, 6.8±0.3 for cysteine, 11.5±1.1 for glutamine, 7.3±0.7 for histidine, 5.9±0.4 for isoleucine, 10.6±0.8 for methionine, 11.2±1.3 for serine, 7.7± 1.0 for threonine, and 6.6±0.6 for valine. We have also measured the temperature dependence of solubility L(T) from 5-40 °C for arginine, glycine, and proline, and obtained hydration numbers H¯(T) in this range. Between 25-40 °C, arginine has an H¯ near zero. This may be evidence for an attractive interaction between xenon and arginine molecules in aqueous solution.

  8. Absorption, metabolism, and excretion of fermented orange juice (poly)phenols in rats.

    Science.gov (United States)

    Escudero-López, Blanca; Calani, Luca; Fernández-Pachón, María-Soledad; Ortega, Angeles; Brighenti, Furio; Crozier, Alan; Del Rio, Daniele

    2014-01-01

    Two milliliters of a fermented, pasteurized orange juice containing ~1% alcohol and 2.3 μmol of (poly)phenolic compounds was fed to rats by gavage after which plasma and urine collected over a 36 h period were analyzed by UHPLC-mass spectrometry. The main constituents in the juice were hesperetin and naringenin-O-glycosides, apigenin-6,8-C-diglucoside, and ferulic acid-4'-O-glucoside. Plasma contained seven flavanone glucuronides, with the principal metabolites, naringenin-7-O-glucuronide, naringenin-4'-O-glucuronide, and an isosakuranetin-O-glucuronide, peaking 6 h after intake at concentrations of ~10 nmol/L. Urinary excretion of four hesperetin glucuronides was equivalent to 0.28% of intake while that of the two naringenin glucuronides was 2.8% of intake. The plasma and urine data suggest that while some absorption occurred in the small intestine, the main site of uptake was the colon. Urine also contained dihydroferulic acid-4'-O-glucuronide and dihydroferulic acid-4'-O-sulfate which were excreted in quantities corresponding to 48.2% of the ingested ferulic acid-4'-glucoside. This indicates that the hydroxycinnamate is much more bioavailable than the flavanones in the rat model. Conversion of the ferulic acid glucoside to the dihydroferulic acid metabolites involves the action of colonic microbial glycosidases and reductases/hydrogenases followed by postabsorption phase II metabolism before renal excretion.

  9. Enrichment of Pb(II) ions using phthalic acid functionalized XAD-16 resin as a sorbent.

    Science.gov (United States)

    Memon, Saima Q; Hasany, S M; Bhanger, M I; Khuhawar, M Y

    2005-11-01

    A simple and reliable method has been developed using polymeric material containing phthalic acid as a chelating agent to concentrate ultratrace amounts of lead ions in aqueous solutions. After characterization by CHN, IR, and thermal studies, the static and dynamic sorption behavior of Pb(II) ions onto new synthetic resin has been investigated. The sorption has been optimized with respect to pH, shaking speed, and contact time between the two phases. Maximum sorption is achieved from solution of pH 5-8 after 10 min agitation time. The lowest concentration for quantitative recovery is 5.8 ng cm(-3) with a preconcentration factor of approximately 850. The kinetics of sorption follows the first-order rate equation with the rate constant k=0.58+/-0.04 min(-1). The variation of the equilibrium constant K(c) with temperature between 10 and 50 degrees C yields values of DeltaH, 52.4+/-1.65 kJmol(-1), DeltaS, 186+/-5.21 Jmol(-1)K(-1), and DeltaG(303K), -4.15+/-0.002 kJmol(-1). The sorption data of Pb(II) ions in the concentration range from 2.41x10(-6) to 1.44x10(-4) molL(-1) follows the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherms at all temperatures investigated. The sorption of Pb(II) ions onto synthesized resin in the presence of common anions and cations has also been measured. The possible sorption mechanism of Pb(II) ions onto phthalic acid modified XAD-16 is also discussed. The sorption procedure is utilized to preconcentrate Pb(II) ions prior to their determination in automobile exhaust particulates by atomic absorption spectrometry using direct and standard addition methods.

  10. Synthesis, crystal structure and Thermogravimetry of ortho-phthalic acid bridged coordination polymer of Copper(II)

    Indian Academy of Sciences (India)

    BABITA SARMA; SAURAV BHARALI; DIGANTA KUMAR DAS

    2016-06-01

    Coordination polymer of Cu(II) bridged by o-phthalic acid alone is not known. The reaction of$CuCl_{2}.2H_{2}O$ with (2-butoxycarbonyl)benzoic acid yielded three dimensional coordination polymer bridged byo-phthalic acid. X-ray crystal structure shows structure with monoclinic P21/c space group. o-Phthalic acidmolecules act as bridge between two Cu(II), one carboxylate binds to one Cu(II) as bidentate while the othercarboxylate binds to another Cu(II) as monodentate. The four planar co-ordination positions of Cu(II) aresatisfied by two chelated carboxylates while fifth and sixth co-ordination positions are satisfied by monodentatecarboxylates. EPR and TGA of the coordination polymer are also reported.

  11. Lewis acid promoted ruthenium(II)-catalyzed etherifications by selective hydrogenation of carboxylic acids/esters.

    Science.gov (United States)

    Li, Yuehui; Topf, Christoph; Cui, Xinjiang; Junge, Kathrin; Beller, Matthias

    2015-04-20

    Ethers are of fundamental importance in organic chemistry and they are an integral part of valuable flavors, fragrances, and numerous bioactive compounds. In general, the reduction of esters constitutes the most straightforward preparation of ethers. Unfortunately, this transformation requires large amounts of metal hydrides. Presented herein is a bifunctional catalyst system, consisting of Ru/phosphine complex and aluminum triflate, which allows selective synthesis of ethers by hydrogenation of esters or carboxylic acids. Different lactones were reduced in good yields to the desired products. Even challenging aromatic and aliphatic esters were reduced to the desired products. Notably, the in situ formed catalyst can be reused several times without any significant loss of activity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Mn(II)/O2-promoted oxidative annulation of vinyl isocyanides with boronic acids: synthesis of multi-substituted isoquinolines.

    Science.gov (United States)

    Wang, Hao; Yu, Yang; Hong, Xiaohu; Xu, Bin

    2014-11-14

    An efficient manganese(II)/O2-promoted oxidative radical cascade reaction was developed for the modular synthesis of multi-substituted isoquinolines from easily accessible vinyl isocyanides and boronic acids.

  13. Complete amino acid sequence of a Lolium perenne (perennial rye grass) pollen allergen, Lol p II.

    Science.gov (United States)

    Ansari, A A; Shenbagamurthi, P; Marsh, D G

    1989-07-05

    The complete amino acid sequence of a Lolium perenne (rye grass) pollen allergen, Lol p II was determined by automated Edman degradation of the protein and selected fragments. Cleavage of the protein by enzymatic and chemical techniques established an unambiguous sequence for the protein. Lol p II contains 97 amino acid residues, with a calculated molecular weight of 10,882. The protein lacks cysteine and glutamine and shows no evidence of glycosylation. Theoretical predictions by Fraga's (Fraga, S. (1982) Can. J. Chem. 60, 2606-2610) and Hopp and Woods' (Hopp, T. P., and Woods, K. R. (1981) Proc. Natl. Acad. Sci. U.S.A. 78, 3824-3828) methods indicate the presence of four hydrophilic regions, which may contribute to sequential or parts of conformational B-cell epitopes. Analysis of amphipathic regions by Berzofsky's method indicates the presence of a highly amphipathic region, which may contain, or contribute to, an Ia/T-cell epitope. This latter segment of Lol p II was found to be highly homologous with an antibody-binding segment of the major rye allergen Lol p I and may explain why immune responsiveness to both the allergens is associated with HLA-DR3.

  14. Campylobacter jejuni fatty acid synthase II: Structural and functional analysis of [beta]-hydroxyacyl-ACP dehydratase (FabZ)

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, Andrew S.; Yokoyama, Takeshi; Choi, Kyoung-Jae; Yeo, Hye-Jeong; (Houston)

    2009-08-14

    Fatty acid biosynthesis is crucial for all living cells. In contrast to higher organisms, bacteria use a type II fatty acid synthase (FAS II) composed of a series of individual proteins, making FAS II enzymes excellent targets for antibiotics discovery. The {beta}-hydroxyacyl-ACP dehydratase (FabZ) catalyzes an essential step in the FAS II pathway. Here, we report the structure of Campylobacter jejuni FabZ (CjFabZ), showing a hexamer both in crystals and solution, with each protomer adopting the characteristic hot dog fold. Together with biochemical analysis of CjFabZ, we define the first functional FAS II enzyme from this pathogen, and provide a framework for investigation on roles of FAS II in C. jejuni virulence

  15. Mechanism of angiotensin II-induced arachidonic acid metabolite release in aortic smooth muscle cells: involvement of phospholipase D.

    Science.gov (United States)

    Shinoda, J; Kozawa, O; Suzuki, A; Watanabe-Tomita, Y; Oiso, Y; Uematsu, T

    1997-02-01

    In a previous study, we have shown that angiotensin II (Ang II) activates phosphatidylcholine-hydrolyzing phospholipase D due to Ang II-induced Ca2+ influx from extracellular space in subcultured rat aortic smooth muscle cells. In the present study, we have investigated the role of phospholipase D in Ang II-induced arachidonic acid (AA) metabolite release and prostacyclin synthesis in subcultured rat aortic smooth muscle cells. Ang II significantly stimulated AA metabolite release in a concentration-dependent manner in the range between 1 nmol/I and 0.1 mumol/I. D.L.-Propranolol hydrochloride (propranolol), an inhibitor of phosphatidic acid phosphohydrolase, significantly inhibited the Ang II-induced release of AA metabolites. The Ang II-induced AA metabolite release was reduced by chelating extracellular Ca2+ with EGTA. Genistein, an inhibitor of protein tyrosine kinases, significantly suppressed the Ang II-induced AA metabolite release. 1,6-Bis-(cyclohexyloximinocarbonylamino)-hexane (RHC-80267), a potent and selective inhibitor of diacylglycerol lipase, significantly inhibited the Ang II-induced AA metabolite release. Both propranolol and RHC-80267 inhibited the Ang II-induced synthesis of 6-keto-prostaglandin F1 alpha, a stable metabolite of prostacyclin. The synthesis was suppressed by genistein. These results strongly suggest that the AA metabolite release induced by Ang II is mediated, at least in part, through phosphatidylcholine hydrolysis by phospholipase D activation in aortic smooth muscle cells.

  16. The Doppler paradigm and the APEX-EPOS-ORANGE quandary

    CERN Document Server

    Griffin, J J

    1996-01-01

    The experimental detection of the sharp lines of the \\ee Puzzle is viewed as a struggle against Doppler broadening. Gedanken experiments which are realistic in zeroth order of detail are analyzed to show that the ORANGE and EPOS/I geometries select narrower slices of a Doppler broadened line than spherically inclusive (APEX and EPOS/II --like) apparati. Roughly speaking, the latter require event-by-event Doppler reconstruction simply to regain an even footing with the former. This suggests that APEX' or EPOS/II's coincident pair distributions must be statistically superior to those of EPOS/I or ORANGE in order to support a comparable inference about sharp structure. Under present circumstances, independent alternative data is invaluable. Therefore, a corroboration of Sakai's 330.1 keV (< 3 keV wide) electron line in few MeV e^+ or e^- bombardments of U and Th targets could prove crucial.

  17. Characterization and performance of carbonaceous materials obtained from exhausted sludges for the anaerobic biodecolorization of the azo dye Acid Orange II

    Energy Technology Data Exchange (ETDEWEB)

    Athalathil, S.; Stüber, F.; Bengoa, C.; Font, J. [Departament d’Enginyeria Quimica, ETSEQ, Universitat Rovira i Virgili, Av. Paisos Catalans 26, 43007 Tarragona, Catalunya (Spain); Fortuny, A. [Departament d’Enginyeria Quimica, EPSEVG, Universitat Politecnica de Catalunya, Av. Victor Balaguer s/n, 08800 Vilanova i la Geltru, Catalunya (Spain); Fabregat, A., E-mail: azael.fabregat@urv.cat [Departament d’Enginyeria Quimica, ETSEQ, Universitat Rovira i Virgili, Av. Paisos Catalans 26, 43007 Tarragona, Catalunya (Spain)

    2014-02-01

    Graphical abstract: - Highlights: • Carbonaceous materials were prepared from exhausted sludge materials. • High surface area and good physicochemical properties were achieved. • Utilization of waste sludge materials and mixed anaerobic cultures were used in a continuous anaerobic UPBR system (upflow packed bed biological reactor). • Effective treatment of dye contaminated wastewater in a cheapest and environmental friendly method was demonstrated. - Abstract: This work presents the preliminary study of new carbonaceous materials (CMs) obtained from exhausted sludge, their use in the heterogeneous anaerobic process of biodecolorization of azo dyes and the comparison of their performance with one commercial active carbon. The preparation of carbonaceous materials was conducted through chemical activation and carbonization. Chemical activation was carried out through impregnation of sludge-exhausted materials with ZnCl{sub 2} and the activation by means of carbonization at different temperatures (400, 600 and 800 °C). Their physicochemical and surface characteristics were also investigated. Sludge based carbonaceous (SBC) materials SBC400, SBC600 and SBC800 present values of 13.0, 111.3 and 202.0 m{sup 2}/g of surface area. Biodecolorization levels of 76% were achieved for SBC600 and 86% for SBC800 at space time (τ) of 1.0 min, similar to that obtained with commercial activated carbons in the continuous anaerobic up-flow packed bed reactor (UPBR). The experimental data fit well to the first order kinetic model and equilibrium data are well represented by the Langmuir isotherm model. Carbonaceous materials show high level of biodecolorization even at very short space times. Results indicate that carbonaceous materials prepared from sludge-exhausted materials have outstanding textural properties and significant degradation capacity for treating textile effluents.

  18. Synthesis, Crystal Structure, and Thermal Decomposition of the Cobalt(II Complex with 2-Picolinic Acid

    Directory of Open Access Journals (Sweden)

    Di Li

    2014-01-01

    Full Text Available The cobalt(II complex of 2-picolinic acid (Hpic, namely, [Co(pic2(H2O2]·2H2O, was synthesized with the reaction of cobalt acetate and 2-picolinic acid as the reactants by solid-solid reaction at room temperature. The composition and structure of the complex were characterized by elemental analysis, infrared spectroscopy, single crystal X-ray diffraction, and thermogravimetry-differential scanning calorimetry (TG-DSC. The crystal structure of the complex belongs to monoclinic system and space group P2(1/n, with cell parameters of a=9.8468(7 Å, b=5.2013(4 Å, c=14.6041(15 Å, β=111.745(6°, V=747.96(11 Å3, Z=2, Dc=1.666 g cm−3, R1=0.0297, and wR2=0.0831. In the title complex, the Co(II ion is six-coordinated by two pyridine N atoms and two carboxyl O atoms from two 2-picolinic acid anions, and two O atoms from two H2O molecules, and forming a slightly distorted octahedral geometry. The thermal decomposition processes of the complex under nitrogen include dehydration and pyrolysis of the ligand, and the final residue is cobalt oxalate at about 450°C.

  19. Antidiabetic effect of glucosaminic acid-cobalt (II chelate in streptozotocin-induced diabetes in mice

    Directory of Open Access Journals (Sweden)

    Talba T

    2011-04-01

    Full Text Available Tahirou Talba1, Xia Wen Shui1, Qinyuan Cheng1,2, Xin Tian21Key Laboratory of Food Processing Technology, 2School of Medicine and Pharmaceutics, Jiangnan University, Wuxi, Jiangsu, People's Republic of ChinaBackground: The purpose of this study was to assess the in vivo ability of glucosaminic acid-cobalt (II chelate to reduce glycemia.Methods: Different concentrations of chelate solution were administrated to mice with diabetes induced by streptozotocin. Daily oral administration of chelate solution 0.4 mL at various concentrations (0.32–0.4 g/mL led to reduction in water intake by the diabetic mice after 5 days of treatment, with a subsequent reduction in glucose levels observed 2 weeks later. Daily food intake was related to both chelate concentration as well as glycemia reduction. The food intake of mice treated with glucosaminic acid-cobalt (II chelate solution was 1.5-fold that of untreated mice.Keywords: glucosaminic acid, cobalt, chelate, streptozotocin, glycemia reduction

  20. Sorption Efficiency of a New Sorbent towards Cadmium(II: Methylphosphonic Acid Grafted Polystyrene Resin

    Directory of Open Access Journals (Sweden)

    Nacer Ferrah

    2013-01-01

    Full Text Available A new chelating polymeric sorbent has been developed using polystyrene resin grafted with phosphonic acid. After characterization by FTIR and elementary analysis, the new resin has been investigated in liquid-solid extraction of cadmium(II. The results indicated that phosphonic resin could adsorb Cd(II ion effectively from aqueous solution. The adsorption was strongly dependent on the pH of the medium and the optimum pH value level for better sorption was between 3.2 and 5.2. The influence of other analytical parameters including contact time, amount of resin, metal ion concentration, and the presence of some electrolytes was investigated. The maximum uptake capacity of Cd(II ions was 37,9 mg·g−1 grafted resin at ambient temperature, at an initial pH value of 5.0. The overall adsorption process was best described by pseudo second-order kinetic. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. Furthermore, more than 92% of Cd(II could be eluted by using 1.0 mol·L−1 HCl in one cycle.

  1. Enhanced anti-topoisomerase II activity by mucoadhesive 4-CBS-chitosan/poly (lactic acid) nanoparticles.

    Science.gov (United States)

    Songsurang, Kultida; Suvannasara, Phruetchika; Phurat, Chuttree; Puthong, Songchan; Siraleartmukul, Krisana; Muangsin, Nongnuj

    2013-11-06

    In this study, the biodegradable mucoadhesive 4-carboxybenzensulfonamide chitosan (4-CBS-chitosan)/poly (lactic acid) (PLA) nanoparticles were fabricated by the electrospray ionization technique for enhancing anti-topoisomerase II (Topo II) activity. The obtained (4-CBS-chitosan/PLA)-DOX nanoparticles were characterized using SEM, particle size analyzer. We emphasis on encapsulation efficiency, in vitro drug release behavior and also performed in vitro studies of Topo II inhibitory activity using gel electrophoresis. In addition, the cytotoxicity of the 4-CBS-chitosan/PLA nanoparticles using MTT assay was also studied. The mean particle size of spherical shaped (4-CBS-chitosan/PLA)-DOX is less than 300 nm. The DOX loaded 4-CBS-chitosan/PLA composite nanoparticles produced high entrapment efficiency of 85.8% and provided the prolonged release of DOX extended to 26 days and also still had strong Topo II inhibitory activity up to 77.4%. Overall, it was shown that 4-CBS-chitosan/PLA nanoparticles could be promising carriers for controlled delivery of anticancer drugs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Study on the adsorption of Cu(II) by folic acid functionalized magnetic graphene oxide

    Science.gov (United States)

    Wang, Cuicui; Ge, Heyi; Zhao, Yueying; Liu, Shanshan; Zou, Yu; Zhang, Wenbo

    2017-02-01

    The folic acid functionalized magnetic graphene oxide (FA-mGO) as a new adsorbent has been synthesized in this work for the elimination of Cu(II) from waste water. The as-prepared FA-mGO was tested by SEM, TEM, particle size analyzer, FTIR, XRD, Roman spectrum, TGA and magnetic properties analyzer. Some factors, such as adsorbent dose, pH, contact time, initial concentration of adsorbate and temperature were explored. The results showed that the FA-mGO had the better adsorption performance than mGO. After 40 min, the adsorption equilibrium could be reached. Furthermore, the adsorption property obeyed the pseudo-second order kinetic model and the Temkin isotherms well. The maximum adsorption capacity was 283.29 mg/g for Cu(II) from Pseudo-second-order model at pH=5 and 318 K. The chelation action between FA and Cu(II) along with electrostatic incorporation between GO and Cu(II) determined the favourable adsorption property. Besides, thermodynamic studies results ∆G00, ∆S0>0 suggested that the adsorption mechanism was an endothermic and spontaneous process essentially. Finally, desorption and reusability studies imply FA-mGO has an excellent reproducibility and is benefit to environmental protection and resource conservation.

  3. Mutual effects of Pb(II) and humic acid adsorption on multiwalled carbon nanotubes/polyacrylamide composites from aqueous solutions.

    Science.gov (United States)

    Yang, Shubin; Hu, Jun; Chen, Changlun; Shao, Dadong; Wang, Xiangke

    2011-04-15

    This paper examines the adsorption of Pb(II) and a natural organic macromolecular compound (humic acid, HA) on polyacrylamide (PAAM) -grafted multiwalled carbon nanotubes (denoted as MWCNTs/PAAM), prepared by an N(2)-plasma-induced grafting technique. The mutual effects of HA/Pb(II) on Pb(II) and HA adsorption on MWCNTs/PAAM, as well as the effects of pH, ionic strength, HA/Pb(II) concentrations, and the addition sequences of HA/Pb(II) were investigated. The results indicated that Pb(II) and HA adsorption were strongly dependent on pH and ionic strength. The presence of HA led to a strong increase in Pb(II) adsorption at low pH and a decrease at high pH, whereas the presence of Pb(II) led to an increase in HA adsorption. The adsorbed HA contributed to modification of adsorbent surface properties and partial complexation of Pb(II) with the adsorbed HA. Different effects of HA/Pb(II) concentrations and addition sequences on Pb(II) and HA adsorption were observed, indicating different adsorption mechanisms. After adsorption of HA on MWCNTs/PAAM, the adsorption capacity for Pb(II) was enhanced at pH 5.0; the adsorption capacity for HA was also enhanced after Pb(II) adsorption on MWCNTs/PAAM. These results are important for estimating and optimizing the removal of metal ions and organic substances by use of MWCNT/PAAM composites.

  4. Part I: Removing of Zn(II from Polluted Water: Determination of Precipitation Limit Of Zn(II Ion With 2-Hydroxy-1,2,3-Propanetricarboxylic Acid

    Directory of Open Access Journals (Sweden)

    Fatmir Faiku

    2010-01-01

    Full Text Available Problem statement: The goal of this research was to investigate the condition for removing of Zn cation from water, through precipitation method with 2-hydroxy-1,2,3-propanetricarboxylic acid as ligand. Approach: In this study we examined the precipitation of Zn(II ion in water solutions of ZnSO4 �� 7H2O (1×10-2 and 5×10-3 mol L-1 with 2-hydroxy-1,2,3-propanetricarboxylic acid (1×10-1-1×10-3 mol L-1 in constant ionic strength of 0.6 mol L-1 NaCl. We have determined the concentration region at which Zn(II start to precipitate. Results: From precipitation diagrams of zinc with 2-hydroxy-1,2,3-propanetricarboxylic acid, in ionic force 0.6 mol L-1 NaCl, we have found that during decreasing the concentration of 2-hydroxy-1,2,3-propanetricarboxylic acid, in case of constant concentration of Zn(II, the limit of precipitation is shifted to lower values of pH. The solid phase is analyzed by IR spectroscopy. Conclusion: From the IR spectroscopic analysis we can conclude that Zn(II ion can precipitate with 2-hydroxy-1,2,3-propanetricarboxylic acid.

  5. Effect of diet orange soda on urinary lithogenicity.

    Science.gov (United States)

    Sumorok, Nicola T; Asplin, John R; Eisner, Brian H; Stoller, Marshall L; Goldfarb, David S

    2012-06-01

    Studies have shown that certain beverages decrease urinary lithogenicity by increasing urine citrate excretion. Diet Sunkist Orange soda had the highest concentration of citrate and total alkali content among 12 diet sodas previously assayed. We studied the effect of Diet Sunkist Orange soda consumption on urinary chemistry. Nine healthy men and women ages 26-54 years completed the study. During the control period, subjects drank 36 oz of water for 3 days in addition to their own, self-selected diet and recorded a food diary. During the study period, the subjects drank three 12-oz cans of Diet Sunkist Orange soda a day instead of water, and replicated their diets from the control period. In each period, the subjects performed 24-h urine collections on days 2 and 3. Urine chemical analysis was performed, including urinary citrate levels and pH. Diet Sunkist Orange soda increased urinary citrate excretion by 60 mg/day, which was not statistically significant (95% CI -75 to 195, P value 0.34). There was no significant change in pH from the control period to the study period (pH: 6.29-6.21; 95% CI: -0.09 to 0.25, P = 0.30). Urine volumes and creatinine excretions were not significantly different between the control and study periods. Despite the relatively high citrate and total alkali content of Diet Sunkist Orange soda, the volume consumed in this study (36 oz per day) did not provide sufficient potential base to significantly alter urine composition in healthy subjects with normocitraturia. The effect of Diet Sunkist Orange soda on urinary chemistry in patients with hypocitraturia and nephrolithiasis is not likely to have a clinically significant effect to prevent calcium or uric acid stones.

  6. Acidification of apple and orange hosts by Penicillium digitatum and Penicillium expansum.

    Science.gov (United States)

    Vilanova, L; Viñas, I; Torres, R; Usall, J; Buron-Moles, G; Teixidó, N

    2014-05-16

    New information about virulence mechanisms of Penicillium digitatum and Penicillium expansum could be an important avenue to control fungal diseases. In this study, the ability of P. digitatum and P. expansum to enhance their virulence by locally modulating the pH of oranges and apples was evaluated. For each host, pH changes with a compatible pathogen and a non-host pathogen were recorded, and the levels of different organic acids were evaluated to establish possible relationships with host pH modifications. Moreover, fruits were harvested at three maturity stages to determine whether fruit maturity could affect the pathogens' virulence. The pH of oranges and apples decreased when the compatible pathogens (P. digitatum and P. expansum, respectively) decayed the fruit. The main organic acid detected in P. digitatum-decayed oranges was galacturonic acid produced as a consequence of host maceration in the rot development process. However, the obtained results showed that this acid was not responsible for the pH decrease in decayed orange tissue. The mixture of malic and citric acids could at least contribute to the acidification of P. digitatum-decayed oranges. The pH decrease in P. expansum decayed apples is related to the accumulation of gluconic and fumaric acids. The pH of oranges and apples was not affected when the non-host pathogen was not able to macerate the tissues. However, different organic acid contents were detected in comparison to healthy tissues. The main organic acids detected in P. expansum-oranges were oxalic and gluconic and in P. digitatum-apples were citric, gluconic and galacturonic. Further research is needed to identify the pathogenicity factors of both fungi because the contribution of organic acids has profound implications.

  7. Dibromidobis(pyrazine-2-carboxylic acid-κN4mercury(II dihydrate

    Directory of Open Access Journals (Sweden)

    Guo-Wei Wang

    2008-01-01

    Full Text Available The asymmetric unit of the title compound, [HgBr2(C5H4N2O22]·2H2O, contains one half-molecule and one water molecule. The HgII ion, lying on a twofold rotation axis, is four-coordinated by two N atoms of pyrazine-2-carboxylic acid ligands and two bromide ions, forming a highly distorted tetrahedral geometry. In the crystal structure, intermolecular O—H...O and O—H...N hydrogen bonds link the molecules.

  8. catena-Poly[[bis(pyridine-3-carboxylic acid-κNmercury(II]-di-μ-chlorido

    Directory of Open Access Journals (Sweden)

    Sadif A. Shirvan

    2012-04-01

    Full Text Available In the title compound, [HgCl2(C6H5NO22]n, the HgII cation is located on an inversion center and is six-coordinated in a distorted octahedral geometry by two N atoms from two pyridine-3-carboxylic acid molecules and four bridging Cl− anions. The bridging function of the Cl− anions leads to polymeric chains running along the a axis. One Hg—Cl bond is much longer than the other. In the crystal, O—H...O and weak C—H...Cl hydrogen bonds are observed.

  9. Fe(II) oxidation during acid mine drainage neutralization in a pilot-scale sequencing batch reactor

    CSIR Research Space (South Africa)

    Zvimba, JN

    2013-10-01

    Full Text Available the suspended solids impacted more positively on Fe(II) oxidation during pilot scale AMD neutralization in a SBR, a phenomenon ascribed to generation of acidity by hydrolysis of Fe(II) as shown in equation 2. Figure 3 shows the chemical behavior... to the acidity generation resulting from hydrolysis of Fe(III) (Reaction 2) that would require further neutralization by CaCO3 (Reaction 3), and as such promotes further CaCO3 dissolution with AMD pH increasing to above 6.8 following complete Fe(II) oxidation...

  10. Removal of Pb(II) ions from aqueous solutions by sulphuric acid-treated wheat bran.

    Science.gov (United States)

    Ozer, A

    2007-03-22

    Sulphuric acid-treated wheat bran (STWB) was used as an adsorbent to remove Pb(II) ions from aqueous solution. It was observed that the adsorption yield of Pb(II) ions was found to be pH dependent. The equilibrium time for the process was determined as 2h. STWB gave the highest adsorption yield at around pH 6.0. At this pH, adsorption percentage for an initial Pb(II) ions concentration of 100mg/L was found to be 82.8 at 25 degrees C for contact time of 2h. The equilibrium data obtained at different temperatures fitted to the non-linear form of Langmuir, Freundlich and Redlich-Peterson and linear form of Langmuir and Freundlich models. Isotherm constants were calculated and compared for the models used. The maximum adsorption capacity (q(max)) which was obtained linear form of Langmuir model increased from 55.56 to 79.37mg/g with increasing temperature from 25 to 60 degrees C. Similar trend was observed for other isotherm constants related to the adsorption capacity. Linear form of Langmuir isotherm data was evaluated to determine the thermodynamic parameters for the process. Thermodynamic parameters show that adsorption process of Pb(II) ions is an endothermic and more effective process at high temperatures. The pseudo nth order kinetic model was successfully applied to the kinetic data and the order (n) of adsorption reaction was calculated at the range from 1.711 to 1.929. The values of k(ad) were found to be 5.82x10(-4) and 21.81x10(-4)(min(-1))(mg/g)(1-n) at 25 and 60 degrees C, respectively. Activation energy was determined as 29.65kJ/mol for the process. This suggest that the adsorption Pb(II) ions by STWB is chemically controlled.

  11. Molecular Mechanics (MM) Force Fields for Modelling of Copper(II) Amino Acid Complexes in Different Environments

    Science.gov (United States)

    Sabolović, Jasmina

    2009-03-01

    New MM force field developed for modelling the properties of copper(II) complexes with aliphatic amino acid in vacuo, in crystal, and in aqueous solution was applied to study conformational properties of bis(N,N-diethylglycinato)copper(II). Two hypotheses are examined and confirmed as true: (i) the conformations which do not allow apical coordination to the copper(II) are the most stable in vacuo and in aqueous solution; (ii) MM calculations quantitatively support the supposition that the experimentally observed conformer is better suited for crystal packing than the in vacuo and in solution most stable conformers.

  12. Orange Peels and Fresnel Integrals

    CERN Document Server

    Bartholdi, Laurent

    2012-01-01

    There are two standard ways of peeling an orange: either cut the skin along meridians, or cut it along a spiral. We consider here the second method, and study the shape of the spiral strip, when unfolded on a table. We derive a formula that describes the corresponding flattened-out spiral. Cutting the peel with progressively thinner strip widths, we obtain a sequence of increasingly long spirals. We show that, after rescaling, these spirals tends to a definite shape, known as the Euler spiral. The Euler spiral has applications in many fields of science. In optics, the illumination intensity at a point behind a slit is computed from the distance between two points on the Euler spiral. The Euler spiral also provides optimal curvature for train tracks between a straight run and an upcoming bend. It is striking that it can be also obtained with an orange and a kitchen knife.

  13. Liquid-liquid extraction of palladium(II) from nitric acid by bis(2-ethylhexyl) sulphoxide

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, J.P. (Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Bombay 400085 (India)); Singh, R.K.; Sawant, S.R.; Varadarajan, N. (Power Reactor Fuel Reprocessing Plant, Bhabha Atomic Research Centre, Trombay, Bombay 400085 (India))

    1993-04-15

    The extraction of palladium(II) nitrate by bis(2-ethylhexyl) sulphoxide (BESO) was evaluated over a wide range of acidity, and BESO was shown to have a strong extraction ability toward this thiophilic 'soft' metal. Essentially quantitative extraction of trace and macro amounts of palladium is easily accomplished from about 8 M HNO 8 M HNO[sub 3] down to pH 2 solutions by 0.2 M BESO into toluene. Optimum conditions such as aqueous phase acidity, solvent, period of equilibration, aqueous to organic phase ratios, reagent concentration and strippant were established for the selective and reversible extraction and separation of palladium. Slope analyses applied to Pd(II) distribution experiments from nitrate solutions showed a predominant formation of the solvated organic phase complex Pd(NO[sub 3])[sub 2].2BESO. Recovery of the extractant from loaded palladium is easily accomplished by using sodium thiosulphate or a mixture of 2 M sodium carbonate+0.5 M ammonia solution. The extracted complex was characterized by elemental analysis and IR and UV-visible spectrometry, and its composition was confirmed to be Pd(NO[sub 3])[sub 2].2BESO

  14. Removal of Mn(II) from the acid mine wastewaters using coal fired bottom ash

    Science.gov (United States)

    Mahidin, M.; Sulaiman, T. N.; Muslim, A.; Gani, A.

    2017-06-01

    Acid mine wastewater (AMW), the wastewater from mining activities which has low pH about 3-5 and contains hazardous heavy metals such as Cu, Fe, Mn, Zn, Pb, etc. Those heavy metals pollution is of prime concern from the environmental view point. Among the heavy metals, Mn occupies the third position in the AMW from one the iron ore mining company in Aceh, Indonesia. In this study, the possibility use of bottom ash from coal fired boiler of steam power plants for the removal of Mn(II) in AMW has been investigated. Experimental has been conducted as follows. Activation of bottom ash was done both by physical and chemical treatments through heating at 270 °C and washing with NaOH activator 0.5 and 1 M. Adsorption test contains two parts observation; preliminary and primary experiments. Preliminary study is addressed to select the best condition of three independent variables i.e.: pH of AMW (3 & 7), bottom ash particle size (40, 60 & 100 mesh) and initial Mn(II) concentrations (100 & 600 mg/l). AMW used was synthetics wastewater. It was found that the best value for NaOH is 1 M, pH is 7, particle size is 100 meshes and initial Mn(II) concentration is 600 mg/l from the adsorption efficiency point of view. The maximum adsorption capacity (q e) is 63.7 mg/g with the efficiency of 85%.

  15. Evaluation of mono or mixed cultures of lactic acid bacteria in type II sourdough system.

    Science.gov (United States)

    Ekinci, Raci; Şimşek, Ömer; Küçükçuban, Ayca; Nas, Sebahattin

    2016-01-01

    The aim of this study was to evaluate the use of mono and mixed lactic acid bacteria (LAB) cultures to determine suitable LAB combinations for a type II sourdough system. In this context, previously isolated sourdough LAB strains with antimicrobial activity, which included Lactobacillus plantarum PFC22, Lactobacillus brevis PFC31, Pediococcus acidilactici PFC38, and Lactobacillus sanfranciscensis PFC80, were used as mono or mixed culture combinations in a fermentation system to produce type II sourdough, and subsequently in bread dough production. Compared to the monoculture fermentation of dough, the use of mixed cultures shortened the adaptation period by half. In addition, the use of mixed cultures ensured higher microbial viability, and enhanced the fruity flavor during bread dough production. It was determined that the combination of L. plantarum PFC22 + P. acidilactici PFC38 + L. sanfranciscensis PFC80 is a promising culture mixture that can be used in the production of type II sourdough systems, and that may also contribute to an increase in metabolic activity during bread production process.

  16. Complexation of mercury(II) ions with humic acids in tundra soils

    Science.gov (United States)

    Vasilevich, R. S.; Beznosikov, V. A.; Lodygin, E. D.; Kondratenok, B. M.

    2014-03-01

    The interaction mechanisms of mercury(II) ions with preparations of humic acids (HAs) isolated from organic horizons of surface-gleyed soils (Haplic Stagnosol (Gelic, Siltic)) of shrub tundra and hydromorphic peat gley soils (Histic Cryosol (Reductaquic, Siltic)) of moss-lichen tundra have been studied. The particular features of the interactions between the mercury(II) ions and the HAs are related to the molecular structure of the HAs, the mercury concentration range, and the environmental parameters. The fixation of mercury(II) ions into stable coordination compounds is most efficient in the pH range of 2.5-3.5. At the element concentrations below 0.50 μmol/dm3, the main complexing sites of HAs are their peripheral aminoacid functional groups. Pyrocatechol, salicylate, and phenolic groups from the nuclear moiety of molecules interact in the concentration range of 0.0005-0.50 mmol/dm3; the physical sorption of mercury hydroxo complexes by the surface of HAs is the main process occurring in the system.

  17. Dissecting the chemical interactions and substrate structural signatures governing RNA polymerase II trigger loop closure by synthetic nucleic acid analogues

    DEFF Research Database (Denmark)

    Xu, Liang; Butler, Kyle Vincent; Chong, Jenny

    2014-01-01

    The trigger loop (TL) of RNA polymerase II (Pol II) is a conserved structural motif that is crucial for Pol II catalytic activity and transcriptional fidelity. The TL remains in an inactive open conformation when the mismatched substrate is bound. In contrast, TL switches from an inactive open...... II. This study reveals novel insights into understanding the molecular basis of TL conformational transition upon substrate binding during Pol II transcription. This synthetic chemical biology approach may be extended to understand the mechanisms of other RNA polymerases as well as other nucleic acid...... state to a closed active state to facilitate nucleotide addition upon the binding of the cognate substrate to the Pol II active site. However, a comprehensive understanding of the specific chemical interactions and substrate structural signatures that are essential to this TL conformational change...

  18. Synthesis and characterization of binary and ternary complexes of Co(II), Ni(II), Cu(II) and Zn(II) ions based on 4-aminotoluene-3-sulfonic acid

    Science.gov (United States)

    Faheim, Abeer A.; Abdou, Safaa N.; Abd El-Wahab, Zeinab H.

    2013-03-01

    Salicylidene (4-aminotoluene-3-sulfonic acid) Schiff base ligand H2L, and its binary and ternary Co(II), Ni(II), Cu(II) and Zn(II) complexes using 8-hydroxyquinoline (8-HOqu) and 2-aminopyridine (2-Ampy) as secondary ligands have been synthesised and characterized via elemental analysis, spectral data (IR, 1H NMR, mass and solid reflectance), molar conductance, magnetic moment, TG-DSC measurements and XRPD analysis. Correlation of all spectroscopic data suggest that H2L ligand acts as monoanionic terdentate ligand with ONO sites coordinating to the metal ions via deprotonated phenolic-O, azomethine-N and sulfonate-O while 2-Ampy behaves as a neutral monodentate ligand via amino group-N and 8-HOqu behaves as a monoanionic bidentate ligand through the ring-N and deprotonated phenolic-O. The thermal behavior of these complexes shows that the coordinated water molecules were eliminated from the complexes at relatively higher temperatures than the hydrated water and there are two routes in removal of coordinated water molecules. All complexes have mononuclear structure and the tetrahedral, square planar or an octahedral geometry have been proposed. The ligand and its complexes have been screened for their antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Salmonella typhimurium, Candida albicans and Aspergillus fumigatus. Among the synthesised compounds, the binary and ternary Ni(II) complexes, (2, 8 and 10) and ternary Zn(II) complex, (12) were found to be very effective against Candida albicans and Bacillus subtilis than all other complexes with MICs of 2 and 8 μg/mL, respectively.

  19. Preparation and Characterization of Bi-metallic and Tri-metallic Metal Organic Frameworks Based on Trimesic Acid and Co(II), Ni(II), and Cu(II) Ions

    Science.gov (United States)

    Sahiner, Nurettin; Demirci, Sahin; Yildiz, Mustafa

    2016-10-01

    Trimesic acid-M1(II):M2(II) (M1,2(II)=M(II)=Co(II), Ni(II) and Cu(II)) bi-metallic or tri-metallic organic frameworks (MOFs) were synthesized by the reaction of trimesic acid (H3BTC) ligand with the corresponding MCl2nH2O aqueous solutions. Here, bi- and tri-metallic MOF preparations were demonstrated by using H3BTC as an organic linker, with dual metal ion mixtures at different mole ratios such as Co(II):Ni(II), Ni(II):Cu(II), and Cu(II):Co(II) as metal ion sources in the synthesis of bi-metallic MOFs, and the triple metal ion mixture of Co(II):Ni(II):Cu(II) as the metal ion source in the synthesis of tri-metallic MOFs. The bi- or tri-metallic MOFs were characterized via the Brunauer-Emmett-Teller method, thermogravimetric analyzer (TGA), and magnetic susceptibility measurements with the Gouy method, FT-IR spectroscopy, and electronic spectral studies. The results revealed that the H3BTC MOFs have octahedral and distorted octahedral arrangement around the metal ions, and the d-d transition was not observed in the complex. It was further found that all the prepared MOFs contain water molecules confirmed by Fourier transform infrared (FT-IR) and TGA analyses. The FT-IR spectra of the MOF complexes were characterized by the appearance of a broad band in the region of 3454-3300 cm-1 due to the ν(-OH) of the coordinated water; therefore, the location of the two water molecules was assumed to be inside the complex structure. Remarkably, the synthesized bi-metallic MOFs had unique and distinct colors depending on the amounts of metal ions used in the feed, implying that these bi-metallic MOFs with tunable M1(II) and M2(II) ratios offer great potential in the design of color-coded materials for use as sensors.

  20. Preparation and Characterization of Bi-metallic and Tri-metallic Metal Organic Frameworks Based on Trimesic Acid and Co(II), Ni(II), and Cu(II) Ions

    Science.gov (United States)

    Sahiner, Nurettin; Demirci, Sahin; Yildiz, Mustafa

    2017-02-01

    Trimesic acid-M1(II):M2(II) (M1,2(II)=M(II)=Co(II), Ni(II) and Cu(II)) bi-metallic or tri-metallic organic frameworks (MOFs) were synthesized by the reaction of trimesic acid (H3BTC) ligand with the corresponding MCl2nH2O aqueous solutions. Here, bi- and tri-metallic MOF preparations were demonstrated by using H3BTC as an organic linker, with dual metal ion mixtures at different mole ratios such as Co(II):Ni(II), Ni(II):Cu(II), and Cu(II):Co(II) as metal ion sources in the synthesis of bi-metallic MOFs, and the triple metal ion mixture of Co(II):Ni(II):Cu(II) as the metal ion source in the synthesis of tri-metallic MOFs. The bi- or tri-metallic MOFs were characterized via the Brunauer-Emmett-Teller method, thermogravimetric analyzer (TGA), and magnetic susceptibility measurements with the Gouy method, FT-IR spectroscopy, and electronic spectral studies. The results revealed that the H3BTC MOFs have octahedral and distorted octahedral arrangement around the metal ions, and the d-d transition was not observed in the complex. It was further found that all the prepared MOFs contain water molecules confirmed by Fourier transform infrared (FT-IR) and TGA analyses. The FT-IR spectra of the MOF complexes were characterized by the appearance of a broad band in the region of 3454-3300 cm-1 due to the ν(-OH) of the coordinated water; therefore, the location of the two water molecules was assumed to be inside the complex structure. Remarkably, the synthesized bi-metallic MOFs had unique and distinct colors depending on the amounts of metal ions used in the feed, implying that these bi-metallic MOFs with tunable M1(II) and M2(II) ratios offer great potential in the design of color-coded materials for use as sensors.

  1. Selective recovery of Pd(II) from extremely acidic solution using ion-imprinted chitosan fiber: Adsorption performance and mechanisms.

    Science.gov (United States)

    Lin, Shuo; Wei, Wei; Wu, Xiaohui; Zhou, Tao; Mao, Juan; Yun, Yeoung-Sang

    2015-12-15

    A novel, selective and acid-resisting chitosan fiber adsorbent was prepared by the ion-imprinting technique using Pd(II) and epichlorohydrin as the template and two-step crosslinking agent, respectively. The resulting ion-imprinted chitosan fibers (IIF) were used to selectively adsorb Pd(II) under extremely acidic synthetic metal solutions. The adsorption and selectivity performances of IIF including kinetics, isotherms, pH effects, and regeneration were investigated. Pd(II) rapidly adsorbed on the IIF within 100 min, achieving the adsorption equilibrium. The isotherm results showed that the maximum Pd(II) uptake on the IIF was maintained as 324.6-326.4 mg g(-1) in solutions containing single and multiple metals, whereas the Pd(II) uptake on non-imprinted fibers (NIF) decreased from 313.7 to 235.3 mg g(-1) in solution containing multiple metals. Higher selectivity coefficients values were obtained from the adsorption on the IIF, indicating a better Pd(II) selectivity. The amine group, supposedly the predominant adsorption site for Pd(II), was confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The pH value played a significant role on the mechanism of the selective adsorption in the extremely acidic conditions. Furthermore, the stabilized performance for three cycles of sorption/desorption shows a potential for further large-scale applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Selective recovery of Pd(II) from extremely acidic solution using ion-imprinted chitosan fiber: Adsorption performance and mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Shuo [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Wei, Wei [School of Chemical Engineering, Chonbuk National University, Jeonbuk 561-756 (Korea, Republic of); Wu, Xiaohui; Zhou, Tao [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Mao, Juan, E-mail: monicamao45@hust.edu.cn [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Yun, Yeoung-Sang, E-mail: ysyun@jbnu.ac.kr [School of Chemical Engineering, Chonbuk National University, Jeonbuk 561-756 (Korea, Republic of)

    2015-12-15

    Highlights: • An acid-resisting chitosan fiber was prepared by ion-imprinting technique. • Pd(II) and ECH were as template and two-step crosslinking agent, respectively. • IIF showed a good adsorption and selectivity performance on Pd(II) solutions. • Selectivity was due to the electrostatic attraction between −NH{sub 3}{sup +} and [PdCl{sub 4}]{sup 2−}. • Stable sorption/desorption performance shows a potential in further application. - Abstract: A novel, selective and acid-resisting chitosan fiber adsorbent was prepared by the ion-imprinting technique using Pd(II) and epichlorohydrin as the template and two-step crosslinking agent, respectively. The resulting ion-imprinted chitosan fibers (IIF) were used to selectively adsorb Pd(II) under extremely acidic synthetic metal solutions. The adsorption and selectivity performances of IIF including kinetics, isotherms, pH effects, and regeneration were investigated. Pd(II) rapidly adsorbed on the IIF within 100 min, achieving the adsorption equilibrium. The isotherm results showed that the maximum Pd(II) uptake on the IIF was maintained as 324.6–326.4 mg g{sup −1} in solutions containing single and multiple metals, whereas the Pd(II) uptake on non-imprinted fibers (NIF) decreased from 313.7 to 235.3 mg g{sup −1} in solution containing multiple metals. Higher selectivity coefficients values were obtained from the adsorption on the IIF, indicating a better Pd(II) selectivity. The amine group, supposedly the predominant adsorption site for Pd(II), was confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The pH value played a significant role on the mechanism of the selective adsorption in the extremely acidic conditions. Furthermore, the stabilized performance for three cycles of sorption/desorption shows a potential for further large-scale applications.

  3. Cd(II) Sorption on Montmorillonite-Humic acid-Bacteria Composites.

    Science.gov (United States)

    Du, Huihui; Chen, Wenli; Cai, Peng; Rong, Xingmin; Dai, Ke; Peacock, Caroline L; Huang, Qiaoyun

    2016-01-21

    Soil components (e.g., clays, bacteria and humic substances) are known to produce mineral-organic composites in natural systems. Herein, batch sorption isotherms, isothermal titration calorimetry (ITC), and Cd K-edge EXAFS spectroscopy were applied to investigate the binding characteristics of Cd on montmorillonite(Mont)-humic acid(HA)-bacteria composites. Additive sorption and non-additive Cd(II) sorption behaviour is observed for the binary Mont-bacteria and ternary Mont-HA-bacteria composite, respectively. Specifically, in the ternary composite, the coexistence of HA and bacteria inhibits Cd adsorption, suggesting a "blocking effect" between humic acid and bacterial cells. Large positive entropies (68.1~114.4 J/mol/K), and linear combination fitting of the EXAFS spectra for Cd adsorbed onto Mont-bacteria and Mont-HA-bacteria composites, demonstrate that Cd is mostly bound to bacterial surface functional groups by forming inner-sphere complexes. All our results together support the assertion that there is a degree of site masking in the ternary clay mineral-humic acid-bacteria composite. Because of this, in the ternary composite, Cd preferentially binds to the higher affinity components-i.e., the bacteria.

  4. Spectrophotometric thermodynamic study of orientational isomers formed by inclusion of methyl orange into β-cyclodextrin nanocavity

    DEFF Research Database (Denmark)

    Kompany Zare, Mohsen; Mokhtari, Zeinab; Abdollahi, Hamid

    2012-01-01

    of methyl orange. This study was performed in basic and acidic media to yield the microconstants and thermodynamic parameters for inclusion complex formation equilibria in each media. The recorded data set at a constant temperature is rank deficient, because there is a linear dependency between...... was also performed, to calculate the microconstants and thermodynamic parameters related to ionization. The interaction of the basic form of methyl orange with β-cyclodextrin in basic medium led to two orientational isomers. In acidic medium methyl orange has two tautomeric forms, called ammonium......Spectrophotometry has been used to investigate the interaction of methyl orange (MO), an azo dye as a guest, with β-cyclodextrin (CD) as the host. Inclusion of methyl orange into β-cyclodextrin nanocavity leads to two orientational isomers, so-called inclumers, because of the asymmetric structure...

  5. Synthesis, Characterization and Thermal Analysis of a New Acetic Acid (2-Hydroxy-benzylidene)-hydrazide and its Complexes with Hg(II) and Pd(II)

    OpenAIRE

    Sahebalzamani, Hajar; GHAMMAMY, Shahriare; Dexhkam, Shaghayegh; Moghadam, Alireza Hemati; Siavoshifar, Farhod

    2011-01-01

    The new complexes have been synthesized by the reaction of Hg(II) and Pd(II) with acetic acid(2-hydroxy-benzylidene)- hydrazide (L). These new complexes were characterized by elemental analysis, IR, H NMR spectroscopy and UV spectral techniques. The changes observed between the FT-IR, H NMR and UV-Vis spectra of the ligands and of the complexes allowed us to establish the coordination mode of the metal in complexes. Thermal properties, TG-DTA of these complexes were studied. TG- DTA and other...

  6. Dissociations of copper(II)-containing complexes of aromatic amino acids: radical cations of tryptophan, tyrosine, and phenylalanine.

    Science.gov (United States)

    Siu, Chi-Kit; Ke, Yuyong; Guo, Yuzhu; Hopkinson, Alan C; Siu, K W Michael

    2008-10-14

    The dissociations of two types of copper(II)-containing complexes of tryptophan (Trp), tyrosine (Tyr), or phenylalanine (Phe) are described. The first type is the bis-amino acid complex, [Cu(II)(M)(2)].(2+), where M = Trp, Tyr, or Phe; the second [Cu(II)(4Cl-tpy)(M)].(2+), where 4Cl-tpy is the tridendate ligand 4'-chloro-2,2':6',2''-terpyridine. Dissociations of the Cu(ii) bis-amino acid complexes produce abundant radical cation of the amino acid, M.(+), and/or its secondary products. By contrast, dissociations of the 4Cl-tpy-bearing ternary complexes give abundant M.(+) only for Trp. Density functional theory (DFT) calculations show that for Tyr and Phe, amino-acid displacement reactions by H(2)O and CH(3)OH (giving [Cu(II)(4Cl-tpy)(H(2)O)].(2+) and [Cu(II)(4Cl-tpy)(CH(3)OH)].(2+)) are energetically more favorable than dissociative electron transfer (giving M.(+) and [Cu(I)(4Cl-tpy)](+)). The fragmentation pathway common to all these [Cu(II)(4Cl-tpy)(M)].(2+) ions is the loss of NH(3). DFT calculations show that the loss of NH(3) proceeds via a "phenonium-type" intermediate. Dissociative electron transfer in [Cu(II)(4Cl-tpy)(M-NH(3))].(2+) results in [M-NH(3)].(+). The [Phe-NH(3)] (+) ion dissociates facilely by eliminating CO(2) and giving a metastable phenonium-type ion that rearranges readily into the styrene radical cation.

  7. Alcoholic fermentation induces melatonin synthesis in orange juice.

    Science.gov (United States)

    Fernández-Pachón, M S; Medina, S; Herrero-Martín, G; Cerrillo, I; Berná, G; Escudero-López, B; Ferreres, F; Martín, F; García-Parrilla, M C; Gil-Izquierdo, A

    2014-01-01

    Melatonin (N-acetyl-5-methoxytryptamine) is a molecule implicated in multiple biological functions. Its level decreases with age, and the intake of foods rich in melatonin has been considered an exogenous source of this important agent. Orange is a natural source of melatonin. Melatonin synthesis occurs during alcoholic fermentation of grapes, malt and pomegranate. The amino acid tryptophan is the precursor of all 5-methoxytryptamines. Indeed, melatonin appears in a shorter time in wines when tryptophan is added before fermentation. The aim of the study was to measure melatonin content during alcoholic fermentation of orange juice and to evaluate the role of the precursor tryptophan. Identification and quantification of melatonin during the alcoholic fermentation of orange juice was carried out by UHPLC-QqQ-MS/MS. Melatonin significantly increased throughout fermentation from day 0 (3.15 ng/mL) until day 15 (21.80 ng/mL) reaching larger amounts with respect to other foods. Melatonin isomer was also analysed, but its content remained stable ranging from 11.59 to 14.18 ng/mL. The enhancement of melatonin occurred mainly in the soluble fraction. Tryptophan levels significantly dropped from 13.80 mg/L (day 0) up to 3.19 mg/L (day 15) during fermentation. Melatonin was inversely and significantly correlated with tryptophan (r = 0.907). Therefore, the enhancement in melatonin could be due to both the occurrence of tryptophan and the new synthesis by yeast. In summary, the enhancement of melatonin in novel fermented orange beverage would improve the health benefits of orange juice by increasing this bioactive compound.

  8. Reliability of acridine orange fluorescence microscopy in oral cytodiagnosis

    Directory of Open Access Journals (Sweden)

    Nilima Prakash

    2011-01-01

    Full Text Available Context and Aims: The oral cavity is the most predominant location in the head and neck region for primary malignant epithelial tumors. Oral cancer is estimated to be the sixth most common malignancy. Early recognition is imperative for successful treatment and good prognosis. Exfoliative cytology is a simple and reasonably effective technique for rapid initial evaluation of a suspicious oral lesion. The present study was conducted to determine the reliability of acridine orange fluorescence microscopy for cytodiagnosis as a more rapid and easier method for the final evaluation of the cytological specimen. Materials and Methods: Smears were collected from 20 individuals with oral lesions suspicious of malignancy, oral lesions not suggestive of malignancy and normal buccal mucosa. One smear was stained with Papanicolaou stain and another one with acridine orange stain. The differences in the study group and control group were compared by means of the χ2 (Chi-square test. The results were considered statistically significant whenever P was <0.05. Results: The acridine orange fluorescence stain reliably demonstrated malignant cells based on the differential fluorescence - a cytochemical criterion. The efficacy of the stain was higher than the conventional Papanicolaou stain in screening of oral lesions suspicious of malignancy. However, the acridine orange fluorescence stain did not differentiate effectively between malignant cells and rapidly proliferating cells, as the technique is based on the nucleic acid content. Conclusion: The fluorescent acridine orange method can be used reliably for the screening of carcinomas and it is especially helpful in the follow-up detection of recurrent carcinoma in previously treated cases.

  9. 生物炭催化过硫酸盐脱色偶氮染料金橙Ⅱ%Biochar Catalyzed Persulfate Decoloration of Azo Dye Acid Orange 7

    Institute of Scientific and Technical Information of China (English)

    刘娜; 王柳; 邱华; Alberto Bento Charru; 王航; 王锐

    2014-01-01

    As a kind of inexpensive material-biochar,the function of soil restoration and other aspects has caused wide public concern,but its catalytic role has been studied rarely.The feasibility of persulfate (PS)catalyzed by biochar(BC)to decolor an azo dye (acid orange (AO7))was studied.Some factors influencing the decolorizing efficiency of PS/BC system were evaluated, including pH, concentration of biochar and PS/AO7 mole ratio.What’s more,the recycle effect and characteristics of biochar were studied.Results showed that the decolorizing effect of the PS/BC system was obviously better than the only PS system.The decoloration of AO7 by both reaction systems followed first order reaction kinetics. The optimum pH of PS/BC system was near-neutral. The higher the biochar concentration,the better the decolorizing effect was.Similar trend was observed for the PS/AO7 mole ratio,whereas the catalytic effect did not increase accordingly.The reused biochar could still decolor %生物炭作为一种廉价易得的材料,在土壤修复等各方面的功能已引起广泛关注,但其催化作用却鲜有研究。首次对生物炭(biochar BC)催化过硫酸盐(Na2 S2 O8 PS)使偶氮染料金橙Ⅱ(AO7)脱色的可行性进行研究,对影响催化体系脱色效率的因素(包括 pH、生物炭质量浓度和 PS/AO7摩尔比)进行探讨,同时研究了生物炭的重复利用效果及前后性质变化。结果表明:PS/BC 体系明显比单独的 PS 体系脱色效果好;两个反应体系都遵循一级反应动力学;PS/BC 体系反应的最适 pH 接近中性;生物炭质量浓度越大,脱色效果越好;PS/AO7摩尔比越大,脱色效果越好,但是催化效果却没有相应的改善;生物炭重复利用后对 AO7仍然有脱色效果;BC 的孔大多位于层状结构表面,且为小孔,重复使用后,表面孔会堵塞;除了灰分和氧元素外,其他元素(C、N、H、S)含量都有一定程度的减小;BC 表面官能团种类很多,主要

  10. Spectroscopic characterization of the competitive binding of Eu(III), Ca(II), and Cu(II) to a sedimentary originated humic acid

    Energy Technology Data Exchange (ETDEWEB)

    Marang, L.; Reiller, P.E. [CEA Saclay, Nucl Energy Div, DPC SECR, Lab Speciat Radionucleides and Mol, 91 - Gif sur Yvette (France); Marang, L.; Benedetti, M.F. [Univ Paris 07, Lab Geochim Eaux, IPGP UMR CNRS 7154, F-75205 Paris 13 (France); Eidner, S.; Kumke, M.U. [Univ Potsdam, Inst Chem, D-14476 Potsdam (Germany)

    2009-06-15

    The competition between REE, alkaline earth and d-transition metals for organic matter binding sites is still an open field of research; particularly, the mechanisms governing these phenomena need to be characterized in more detail. In this study, we examine spectroscopically the mechanisms of competitive binding of Eu(III)/Cu(II) and Eu(III)/Ca(II) pair to Gorleben humic acid (HA), as previously proposed in the framework of the NICA-Donnan model. The evolution of time-resolved laser induced luminescence spectra of humic-complexed Eu(Ill) showed two strikingly different environments for a comparable bound proportion for Cu(II) and Ca(II). Cu(II) seems to compete more effectively with Eu(III) inducing its release into the Donnan phase, and into the bulk solution as free Eu{sup 3+}. This is evidenced both by the shapes of the spectra and by the decrease in the luminescence decay times. In contrast with that, Ca(II) induces a modification of the HA structure, which enhances the luminescence of humic-bound Eu(III), and causes a minor modification of the chemical environment of the complexed rare earth ion. (authors)

  11. Mn(II) complexes with bipyridine, phenanthroline and benzoic acid: Biological and catalase-like activity

    Indian Academy of Sciences (India)

    Ibrahim Kani; Özlem Atlier; Kiymet Güven

    2016-04-01

    Five mononuclear Mn(II) complexes, [Mn(phen)2(ClO4)2] (1), [Mn(phen)3](ClO4)2(H2CO3)2(2), [Mn(bipy)2(ClO4)2] (3), [Mn(bipy)3](ClO4)2) (4), and Mn(phen)2(ba)(H2O)](ClO4)(CH3OH) (5), where bipy = 2,2’-bipyridine, phen = 1,10-phenanthroline, and ba = benzoic acid were prepared and characterized by Xray, IR and UV-Vis spectroscopies, and their catalase-like and biological activities were studied. The presence of two different types and the number of chelating NN-donor neutral ligands allowed for analysis of their effects on the catalase and biological activities. It was observed that the presence and number of phen ligands improved the activity more than the bipy ligand. Complexes 1 and 2, which contain more basic phen ligands, disproportionate H2O2 faster than complexes 3 and 4, which contain less basic bipy ligands. The in vitro antimicrobial activities of all the complexes were also tested against seven bacterial strains by microdilution tests. All the bacterial isolates demonstrated sensitivity to the complexes and the antifungal (anticandidal) activities of the Mn(II) complexes were remarkably higher than the reference drug ketoconazole.

  12. Synthesis and characterization of tin(II) complexes of fluorinated Schiff bases derived from amino acids.

    Science.gov (United States)

    Singh, Har Lal

    2010-07-01

    New tin(II) complexes of general formula Sn(L)(2) (L=monoanion of 3-methyl-4-fluoro-acetophenone phenylalanine L(1)H, 3-methyl-4-fluoro-acetophenone alanine L(2)H, 3-methyl-4-fluoro acetophenone tryptophan L(3)H, 3-methyl-4-fluoro-acetophenone valine L(4)H, 3-methyl-4-fluoro-acetophenone isoleucine L(5)H and 3-methyl-4-fluoro-acetophenone glycine L(6)H) have been prepared. It is characterized by elemental analyses, molar conductance measurements and molecular weight determinations. Bonding of these complexes is discussed in terms of their UV-visible, infrared, and nuclear magnetic resonance ((1)H, (13)C, (19)F and (119)Sn NMR) spectral studies. The ligands act as bidentate towards metal ions, via the azomethine nitrogen and deprotonated oxygen of the respective amino acid. Elemental analyses and NMR spectral data of the ligands with their tin(II) complexes agree with their proposed square pyramidal structures. A few representative ligands and their tin complexes have been screened for their antibacterial activities and found to be quite active in this respect. Copyright 2010 Elsevier B.V. All rights reserved.

  13. Aspartic acid interaction with cobalt(II) in dilute aqueous solution: A {sup 57}Co emission Moessbauer spectroscopic study

    Energy Technology Data Exchange (ETDEWEB)

    Kamnev, Alexander A.; Tugarova, Anna V. [Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences (Russian Federation); Kovacs, Krisztina; Homonnay, Zoltan, E-mail: homonnay@ludens.elte.hu; Kuzmann, Erno; Vertes, Attila [Eoetvoes Lorand University, Institute of Chemistry (Hungary)

    2012-03-15

    Emission ({sup 57}Co) Moessbauer spectra of the aspartic acid-{sup 57}CoCl{sub 2} system were measured at T = 80 K in frozen aqueous solution and in the form of a dried residue of this solution. The Moessbauer spectra, besides a weak contribution from after-effects, showed two Fe{sup 2 + }/Co{sup 2 + } components which were ascribed to octahedrally and tetrahedrally coordinated {sup 57}Co{sup II} microenvironments in the Asp-cobalt(II) complex. This dual coordination mode may be due to the involvement of the second terminal carboxylic group of aspartic acid in the coordination sphere of Co.

  14. Interactive Network Exploration with Orange

    Directory of Open Access Journals (Sweden)

    Miha Štajdohar

    2013-04-01

    Full Text Available Network analysis is one of the most widely used techniques in many areas of modern science. Most existing tools for that purpose are limited to drawing networks and computing their basic general characteristics. The user is not able to interactively and graphically manipulate the networks, select and explore subgraphs using other statistical and data mining techniques, add and plot various other data within the graph, and so on. In this paper we present a tool that addresses these challenges, an add-on for exploration of networks within the general component-based environment Orange.

  15. Synthesis, Spectroscopic Characterization, and In Vitro Antimicrobial Studies of Pyridine-2-Carboxylic Acid N′-(4-Chloro-Benzoyl-Hydrazide and Its Co(II, Ni(II, and Cu(II Complexes

    Directory of Open Access Journals (Sweden)

    Jagvir Singh

    2012-01-01

    Full Text Available N-substituted pyridine hydrazide (pyridine-2-carbonyl chloride and 4-chloro-benzoic acid hydrazide undergoes hydrazide formation of the iminic carbon nitrogen double bond through its reaction with cobalt(II, nickel(II, and copper(II metal salts in ethanol which are reported and characterized based on elemental analyses, IR, solid reflectance, magnetic moment, molar conductance, and thermal analysis (TG. From the elemental analyses data, 1 : 2 metal complexes are formed having the general formulae [MCl2(HL2] · yH2O (where M = Co(II, Ni(II, and Cu(II, y = 1–3. The important infrared (IR spectral bands corresponding to the active groups in the ligand and the solid complexes under investigation were studied. IR spectra show that ligand is coordinated to the metal ions in a neutral bidentate manner with ON donor sites. The solid complexes have been synthesized and studied by thermogravimetric analysis. All the metal chelates are found to be nonelectrolytes. From the magnetic and solid reflectance spectra, the complexes (cobalt(II, nickel(II, and copper(II have octahedral and square planner geometry, respectively. The antibacterial and antifungal activity’s data show that the metal complexes have a promising biological activity comparable with the parent ligand against bacterial and fungal species.

  16. Effects of microwave roasting on the yield and composition of cold pressed orange seed oils

    Directory of Open Access Journals (Sweden)

    B. Aydeniz Güneşer

    2017-03-01

    Full Text Available The aim of this study was to valorize orange (Citrus sinensis seeds, which are generated as waste. This study presents data about raw orange seed, the meal gained after cold pressing, and characterization data of the cold pressed seed oils. Furthermore, the effects of microwave roasting of the seds compared to regular roasting (control were determined. The oil yield of orange seed cold pressing was around 52.93–62.99%. After cold pressing, 13.57–17.97% oil remained in the meal together with 20.68–25.61% protein. Hence, pressed meals could be valorized for different purposes. Except for turbidity, the color b* value, free acidity, the p-anisidine value and antioxidant capacity, there was no significant difference between the two oil samples for the measured physicochemical properties. Six different fatty acids were quantified and the major fatty acids were linoleic, palmitic and oleic acids. The fatty acid composition of the orange seed oil can be accepted as nutritionally balanced. Among the fifteen sterols quantified, ß-sitosterol was dominant (around 77–78%. Likewise, the α-tocopherol content of the samples was not significantly different. The thermal onset and peak temperatures, and enthalpies for crystallization and melting were also reported. This study showed that good quality orange seed oils can be produced by cold pressing, and the oils could be used in food and non-food applications.

  17. Structural elucidation of the hormonal inhibition mechanism of the bile acid cholate on human carbonic anhydrase II

    Energy Technology Data Exchange (ETDEWEB)

    Boone, Christopher D. [University of Florida, PO Box 100267, Gainesville, FL 32610 (United States); Tu, Chingkuang [University of Florida, PO Box 100245, Gainesville, FL 32610 (United States); McKenna, Robert, E-mail: rmckenna@ufl.edu [University of Florida, PO Box 100267, Gainesville, FL 32610 (United States)

    2014-06-01

    The structure of human carbonic anhydrase II in complex with cholate has been determined to 1.54 Å resolution. Elucidation of the novel inhibition mechanism of cholate will aid in the development of a nonsulfur-containing, isoform-specific therapeutic agent. The carbonic anhydrases (CAs) are a family of mostly zinc metalloenzymes that catalyze the reversible hydration/dehydration of CO{sub 2} into bicarbonate and a proton. Human isoform CA II (HCA II) is abundant in the surface epithelial cells of the gastric mucosa, where it serves an important role in cytoprotection through bicarbonate secretion. Physiological inhibition of HCA II via the bile acids contributes to mucosal injury in ulcerogenic conditions. This study details the weak biophysical interactions associated with the binding of a primary bile acid, cholate, to HCA II. The X-ray crystallographic structure determined to 1.54 Å resolution revealed that cholate does not make any direct hydrogen-bond interactions with HCA II, but instead reconfigures the well ordered water network within the active site to promote indirect binding to the enzyme. Structural knowledge of the binding interactions of this nonsulfur-containing inhibitor with HCA II could provide the template design for high-affinity, isoform-specific therapeutic agents for a variety of diseases/pathological states, including cancer, glaucoma, epilepsy and osteoporosis.

  18. Electrodialytic separation of Cu(II) and As(V) in acidic electrolytes; Separacion electrodialitica de Cu(II) y As(V) en electrolitos acidos

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, J. P.; Ipinza, J.; Cifuentes, L.

    2007-07-01

    The separation of copper and arsenic from acidic electrolytes by electrodialysis was investigated at room temperature. the effect of current density and pH was studied in a batch cell during 3 hours. The kinetic parameters showed that Cu(II) transport rate was 0.75 mol/m''2/h and the As(V) transport rate was 0.002 mol/m''2/h. An efficient separation between Cu(II) and As(V) was achieved; Generating a concentrated solution of copper with no arsenic, which was obtained independently of the electrolyte acidity and current density used. The effect of the arsenic speciation with pH is discussed as well. (Author) 23 refs.

  19. EFFECT OF DIATOMEAOUS EARTH TREATMENT USING HYDROGEN CHLORIDE AND SULFURIC ACID ON KINETICS OF CADMIUM(II ADSORPTION

    Directory of Open Access Journals (Sweden)

    Nuryono Nuryono

    2010-06-01

    Full Text Available In this research, treatment of diatomaceous earth, Sangiran, Central Java using hydrogen chloride (HCl and sulfuric acid (H2SO4 on kinetics of Cd(II adsorption in aqueous solution has been carried out. The work was conducted by mixing an amount of grounded diatomaceous earth (200 mesh in size with HCl or H2SO4 solution in various concentrations for two hours at temperature range of 100 - 150oC. The mixture was then filtered and washed with water until the filtrate pH is approximately 7 and then the residue was dried for four hours at a temperature of 70oC. The product was used as an adsorbent to adsorb Cd(II in aqueous solution with various concentrations. The Cd(II adsorbed was determined by analyzing the rest of Cd(II in the solution using atomic absorption spectrophotometry. The effect of treatment was evaluated from kinetic parameter of adsorption rate constant calculated based on the simple kinetic model. Results showed  that before equilibrium condition reached, adsorpstion of Cd(II occurred through two steps, i.e. a step tends to follow a reaction of irreversible first order  (step I followed by reaction of reversible first order (step II. Treatment with acids, either hydrogen chloride or sulfuric acid, decreased adsorption rate constant for the step I from 15.2/min to a range of 6.4 - 9.4/min.  However, increasing concentration of acid (in a range of concentration investigated did not give significant and constant change of adsorption rate constant. For step II process,  adsorption involved physical interaction with the sufficient low adsorption energy (in a range of 311.3 - 1001 J/mol.     Keywords: adsorption, cdmium, diatomaceous earth, kinetics.

  20. Citrus pulp pellets as an additive for orange bagasse silage

    Directory of Open Access Journals (Sweden)

    R. K. Grizotto

    2017-03-01

    Full Text Available This study evaluated the fermentation profile of orange bagasse ensiled with three levels of dry matter (DM using citrus pulp pellets as a moisture-absorbing additive. Thirty experimental silos (3 treatments, 5 storage times, 2 replicates were prepared using 25-liter plastic buckets containing orange bagasse and three levels of pelleted citrus pulp (0, 6% and 20% as additive. A completely randomized design with repeated measures over time was used. The periods of anaerobic storage were 3, 7, 14, 28 and 56 days. Natural orange bagasse contained 13.9% DM, which increased to 19.1% and 25.5% with the inclusion of 6% and 20% citrus pulp pellets, respectively. The apparent density was inversely correlated with DM content and a higher level of compaction (982 kg/m3 was observed in the mass ensiled with the lowest DM level (13.9%. Additionally, lower compaction (910 kg/m3 was found in the mass ensiled with the additive. The chemical composition of the mass ensiled with or without citrus pulp pellets did not differ significantly in terms of protein, ether extract, neutral detergent fiber, lignin or in vitro DM digestibility (P≥0.05, as expected. Thus, it was possible to analyze only the effect of the inclusion of citrus pulp pellets on the increase in DM content. The inclusion of 20% of the additive reduced (P<0.01 losses due to effluent (98% less and gas production (81% less compared to the control treatment at the end of the anaerobic storage period. In this treatment, a higher (P≤0.05 log number of lactic acid bacteria (4.61 log CFU/g was also observed compared to the other treatments, indicating that the increase in DM favored the growth of these bacteria. In addition, the low yeast count (about 1 log CFU/g sample and the pH below 4.0, which were probably due to the production of lactic and acetic acids, show that the orange bagasse is rich in fermentable soluble carbohydrates and is indicated for ensiling. In conclusion, orange bagasse can be

  1. Ukraine’s Orange Revolution

    Directory of Open Access Journals (Sweden)

    Seyyed Ali Mortazavi Emami

    2013-05-01

    Full Text Available Color revolution is one of the new ways of changing a regime at the beginning of the twenty-first century, which has usually been carried out on corrupt, political systems remaining from the Cold War era in Eastern European countries and countries that have become independent from the former Soviet Union and through such revolution a new peaceful form of political power transition emerged. An exploration of the circumstances of Ukraine’s Orange Revolution suggests foreigners’ support and leading. Ukraine’s presidential elections of 2004 and the competition between Viktor Yushchenko and Victor Yanukovich and the presence of international observers in the process of elections and the controversy of electoral fraud and the West’s support of Yushchenko were all directed toward the formation of a color revolution in Ukraine. Poor economic conditions and official corruption, religious, linguistic, class and racial gaps in Ukraine led the way for foreigners to use them in creating electoral situations and prepare the fall of the government. The main purpose question in this article is the Orange Revolution and its causes.

  2. Tracking the degradation of fresh orange juice and discrimination of orange varieties: an example of NMR in coordination with chemometrics analyses.

    Science.gov (United States)

    de Oliveira, Clayton R; Carneiro, Renato L; Ferreira, Antonio G

    2014-12-01

    Brazil is currently the largest exporter of concentrated orange juice and, unlike the other exporter countries, the domestic consumption is mainly based on the fresh orange juice. The quality control by evaluating the major chemical constituents under the influence of the most important factors, such as temperature and storage time of the product, is very important in this context. Therefore, the objective of this study was to evaluate the influence of temperature and time on the degradation of fresh orange juice for 24h, by using (1)H NMR technique and chemometric tools for data mining. The storage conditions at 24h led to the production of the formic, fumaric and acetic acids; and an increase of succinic and lactic acids and ethanol, which were observed at low concentration at the initial time. Furthermore, analysis by PCA has successfully distinguished the juice of different species/varieties as well as the metabolites responsible for their separation.

  3. High specificity of human secretory class II phospholipase A2 for phosphatidic acid.

    Science.gov (United States)

    Snitko, Y; Yoon, E T; Cho, W

    1997-02-01

    Lysophosphatidic acid (LPA) is a potent lipid second messenger which stimulates platelet aggregation, cell proliferation and smooth-muscle contraction. The phospholipase A2 (PLA2)-catalysed hydrolysis of phosphatidic acid (PA) is thought to be a primary synthetic route for LPA. Of the multiple forms of PLA2 present in human tissues, human secretory class-II PLA2 (hs-PLA2) has been implicated in the production of LPA from platelets and whole blood cells challenged with inflammatory stimuli. To explore further the possibility that hs-PLA2 is involved in the production of LPA, we rigorously measured the phospholipid head group specificity of hs-PLA2 by a novel PLA2 kinetic system using polymerized mixed liposomes. Kinetic analysis of recombinant hs-PLA2 demonstrates that hs-PLA2 strongly prefers PA as substrate over other phospholipids found in the mammalian plasma membrane including phosphatidylserine (PS), phosphatidylcholine (PC) and phosphatidylethanolamine (PE). The order of preference is PA > PE approximately PS > PC. To identify amino acid residues of hs-PLA2 that are involved in its unique substrate specificity, we mutated two residues, Glu-56 and Lys-69, which were shown to interact with the phospholipid head group in the X-ray-crystallographic structure of the hs-PLA2-transition-state-analogue complex. The K69Y mutant showed selective inactivation toward PA whereas the E56K mutant displayed a most pronounced inactivation to PE. Thus it appears that Lys-69 is at least partially involved in the PA specificity of hs-PLA2 and Glu-56 in the distinction between PE and PC. In conjunction with a recent cell study [Fourcade, Simon, Viode, Rugani, Leballe, Ragab, Fournie, Sarda and Chap (1995) Cell 80, 919-927], these studies suggest that hs-PLA2 can rapidly hydrolyse PA molecules exposed to the outer layer of cell-derived microvesicles and thereby produce LPA.

  4. Investigating the effect of antioxidant extract from orange peel on lipids oxidation

    Directory of Open Access Journals (Sweden)

    Uduak G. AKPAN*

    2015-12-01

    Full Text Available This research involved investigation of the extraction yield and antioxidant property of orange peel on lipid oxidation. Orange peel was oven dried, grinded to powder and extraction procedure carried out using methanol as solvent in a soxhlet extractor. The effects of time and temperature on the extraction process were considered and results obtained showed an optimum extraction temperature and time of 50ºC and 120 minutes respectively. X-ray fluorescence analysis of the orange peel extract showed that potassium and calcium are the major elements by percentag mposition of 55.5 and 32.65 respectively. In studying the effects of oran eel extract on the melon oil sample, peroxide, free fatty acid and pH analysis were carried out for a period of 60 day. The result obtained confirmed the of ability orange peel extract as antioxidant agent.

  5. Measuring Vitamin C Content of Commercial Orange Juice Using a Pencil Lead Electrode

    Science.gov (United States)

    King, David; Friend, Jeffrey; Kariuki, James

    2010-01-01

    A pencil lead successfully served as an electrode for the determination of ascorbic acid in commercial orange juice. Cyclic voltammetry was used as an electrochemical probe to measure the current produced from the oxidation of ascorbic acid with a variety of electrodes. The data demonstrate that the less expensive pencil lead electrode gives…

  6. Measuring Vitamin C Content of Commercial Orange Juice Using a Pencil Lead Electrode

    Science.gov (United States)

    King, David; Friend, Jeffrey; Kariuki, James

    2010-01-01

    A pencil lead successfully served as an electrode for the determination of ascorbic acid in commercial orange juice. Cyclic voltammetry was used as an electrochemical probe to measure the current produced from the oxidation of ascorbic acid with a variety of electrodes. The data demonstrate that the less expensive pencil lead electrode gives…

  7. Antibacterial, antibiofilm and antioxidant screening of copper(II)-complexes with some S-alkyl derivatives of thiosalicylic acid. Crystal structure of the binuclear copper(II)-complex with S-propyl derivative of thiosalicylic acid

    Science.gov (United States)

    Bukonjić, Andriana M.; Tomović, Dušan Lj.; Nikolić, Miloš V.; Mijajlović, Marina Ž.; Jevtić, Verica V.; Ratković, Zoran R.; Novaković, Slađana B.; Bogdanović, Goran A.; Radojević, Ivana D.; Maksimović, Jovana Z.; Vasić, Sava M.; Čomić, Ljiljana R.; Trifunović, Srećko R.; Radić, Gordana P.

    2017-01-01

    The spectroscopically predicted structure of the obtained copper(II)-complex with S-propyl derivative of thiosalicylic acid was confirmed by X-ray structural study. The binuclear copper(II)-complex with S-propyl derivative of thiosalicylic acid crystallized in two polymorphic forms with main structural difference in the orientation of phenyl rings relative to corresponding carboxylate groups. The antibacterial activity was tested determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by using microdilution method. The influence on bacterial biofilm formation was determined by tissue culture plate method. In general, the copper(II)-complexes manifested a selective and moderate activity. The most sensitive bacteria to the effects of Cu(II)-complexes was a clinical isolate of Pseudomonas aeruginosa. For this bacteria MIC and biofilm inhibitory concentration (BIC) values for all tested complexes were in the range or better than the positive control, doxycycline. Also, for the established biofilm of clinical isolate Staphylococcus aureus, BIC values for the copper(II)-complex with S-ethyl derivative of thiosalicylic acid,[Cu2(S-et-thiosal)4(H2O)2] (C3) and copper(II)-complex with S-butyl derivative of thiosalicylic acid, [Cu2(S-bu-thiosal)4(H2O)2] (C5) were in range or better than the positive control. All the complexes acted better against Gram-positive bacteria (Staphylococcus aureus and Staphylococcus aureus ATCC 25923) than Gram-negative bacteria (Proteus mirabilis ATCC 12453, Pseudomonas aeruginosa, and P. aeruginosa ATCC 27855). The complexes showed weak antioxidative properties tested by two methods (1,1-diphenyl-2-picrylhydrazyl (DPPH) and reducing power assay).

  8. Metabolomic comparative analysis of the phloem sap of curry leaf tree (Bergera koenegii), orange jasmine (Murraya paniculata), and Valencia sweet orange (Citrus sinensis) supports their differential responses to Huanglongbing.

    Science.gov (United States)

    Killiny, Nabil

    2016-11-01

    Orange jasmine, Murraya paniculata and curry leaf tree, Bergera koenegii are alternative hosts for Diaphorina citri, the vector of Candidatus Liberibacter asiaticus (CLas), the pathogen of huanglongbing (HLB) in citrus. D. citri feeds on the phloem sap where CLas grows. It has been shown that orange jasmine was a better host than curry leaf tree to D. citri. In addition, CLas can infect orange jasmine but not curry leaf tree. Here, we compared the phloem sap composition of these 2 plants to the main host, Valencia sweet orange, Citrus sinensis. Phloem sap was analyzed by gas chromatography-mass spectrometry after trimethylsilyl derivatization. Orange jasmine was the highest in proteinogenic, non-proteinogenic amino acids, organic acids, as well as total metabolites. Valencia was the highest in mono- and disaccharides, and sugar alcohols. Curry leaf tree was the lowest in most of the metabolites as well as total metabolites. Interestingly, malic acid was high in Valencia and orange jasmine but was not detected in the curry leaf. On the other hand, tartaric acid which can prevent the formation of malic acid in Krebs cycle was high in curry leaf. The nutrient inadequacy of the phloem sap in curry leaf tree, especially the amino acids could be the reason behind the longer life cycle and the low survival of D. citri and the limitation of CLas growth on this host. Information obtained from this study may help in cultivation of CLas and development of artificial diet for rearing of D. citri.

  9. 76 FR 5822 - Orange Juice From Brazil

    Science.gov (United States)

    2011-02-02

    ... to consider include technology; production methods; development efforts; ability to increase... COMMISSION Orange Juice From Brazil AGENCY: United States International Trade Commission. ACTION: Institution of a five-year review concerning the antidumping duty order on certain orange juice from Brazil...

  10. Neutron activation analysis of thin orange pottery

    Energy Technology Data Exchange (ETDEWEB)

    Harbottle, G; Sayre, E V; Abascal, R

    1976-01-01

    The evidence thus far obtained supports the idea of ''Thin Orange'' ware, typical of classic Teotihuacan culture, easily identifiable petrographically or chemically, not necessarily made at Teotihuacan itself but widely traded, and ''thin, orange'' pottery, fabricated in many other places, and perhaps at other times as well.

  11. Trouble Brewing in Orange County. Policy Brief

    Science.gov (United States)

    Buck, Stuart

    2010-01-01

    Orange County will soon face enormous budgetary pressures from the growing deficits in public pensions, both at a state and local level. In this policy brief, the author estimates that Orange County faces a total $41.2 billion liability for retiree benefits that are underfunded--including $9.4 billion for the county pension system and an estimated…

  12. Removal of Cr(III), Ni(II) and Cu(II) by poly(gamma-glutamic acid) from Bacillus subtilis NX-2.

    Science.gov (United States)

    Yao, Jun; Xu, Hong; Wang, Jun; Jiang, Min; Ouyang, Pingkai

    2007-01-01

    Poly(gamma-glutamic acid) (gamma-PGA) derived from Bacillus subtilis NX-2 was investigated as a sorbent for heavy metal ions in batch adsorption experiments. The results showed that the heavy metal adsorption capacity of gamma-PGA enhanced with the increase of pH, in the following order: Cr(III) > Cu(II) > Ni(II), within the pH range 3-5. The Langmuir sorption model effectively described the metal sorption of y-PGA through the experiments of isotherm sorption, and it was deduced that the affinity of gamma-PGA for metals was following the sequence: Cr(III) > Cu(II) > Ni(II). Gamma-PGA was also used to trap trace amounts of heavy metals from the electroplating wastewater, which were difficult to be entirely removed by the traditional hydroxide precipitation method. The results showed that Cr(III) and Ni(II) in the electroplating effluent decreased from 3.07 and 9.46 mg/l to 0.15 and 1.01 mg/l, respectively, and the treated solutions reached the effluent standard. Therefore, gamma-PGA is satisfactory as a well biosorbent for the removal of heavy metals. The adsorption mechanism of gamma-PGA binding heavy metals was also studied using HyperChem simulation and FT-IR.

  13. Simultaneous extraction of Cr(VI) and Cu(II) from humic acid with new synthesized EDTA derivatives.

    Science.gov (United States)

    Zhang, Tao; Wu, Ying-Xin; Huang, Xiong-Fei; Liu, Jun-Min; Xia, Bing; Zhang, Wei-Hua; Qiu, Rong-Liang

    2012-07-01

    Soil washing is one of the few permanent treatment alternatives for removing metal contaminants. Ethylenediaminetetraacetic acid and its salts (EDTA) is very effective at removing cationic metals and has been utilized globally. However it is ineffective for anionic metal contaminants or metals bound to soil organic matter. The simultaneous removal of cationic and anionic metal contaminants by soil washing is difficult due to differences in their properties. The present study evaluated the potential of a washing process using two synthesized EDTA-derivatives, C(6)HEDTA (2,2'-((2-((carboxymethyl)(2-(hexanoyloxy)ethyl)amino)ethyl)azanediyl)diacetic acid) and C(12)HEDTA (2,2'-((2-((carboxymethyl) (2-(dodecanoyloxy)ethyl)amino)ethyl)azanediyl)diacetic acid), which consist of a hydrophilic polycarboxylic moiety and a hydrophobic moiety with a monoalkyl ester group. A series of equilibrium batch experiments at room temperature were conducted to investigate the efficacy of C(6)HEDTA and C(12)HEDTA as extractants for both oxyanion Cr(VI) and cationic Cu(II). Results showed that either C(6)HEDTA or C(12)HEDTA can extract both Cr(VI) and Cu(II) from humic acid simultaneously. However, C(6)HEDTA was less effective for Cr(VI) probably because it has no surface activities to increase solubility of humic acid, like C(12)HEDTA. Extraction of Cr(VI) was mainly attributed to the decreased surface tension and enhanced solubility of organic matter. Extraction of Cu(II) was attributed to both the Cu(II) chelation and enhanced solubility of humic acid. It was demonstrated that the hydrophilic polycarboxylic moiety of C(12)HEDTA chelates cations while the monoalkyl ester group produces surface active properties that enhance the solubility of humic acid.

  14. Synergistic removal of Pb(II, Cd(II and humic acid by Fe3O4@mesoporous silica-graphene oxide composites.

    Directory of Open Access Journals (Sweden)

    Yilong Wang

    Full Text Available The synergistic adsorption of heavy metal ions and humic acid can be very challenging. This is largely because of their competitive adsorption onto most adsorbent materials. Hierarchically structured composites containing polyethylenimine-modified magnetic mesoporous silica and graphene oxide (MMSP-GO were here prepared to address this. Magnetic mesoporous silica microspheres were synthesized and functionalized with PEI molecules, providing many amine groups for chemical conjugation with the carboxyl groups on GO sheets and enhanced the affinity between the pollutants and the mesoporous silica. The features of the composites were characterized using TEM, SEM, TGA, DLS, and VSM measurements. Series adsorption results proved that this system was suitable for simultaneous and efficient removal of heavy metal ions and humic acid using MMSP-GO composites as adsorbents. The maximum adsorption capacities of MMSP-GO for Pb(II and Cd (II were 333 and 167 mg g(-1 caculated by Langmuir model, respectively. HA enhances adsorption of heavy metals by MMSP-GO composites due to their interactions in aqueous solutions. The underlying mechanism of synergistic adsorption of heavy metal ions and humic acid were discussed. MMSP-GO composites have shown promise for use as adsorbents in the simultaneous removal of heavy metals and humic acid in wastewater treatment processes.

  15. Synergistic removal of Pb(II), Cd(II) and humic acid by Fe3O4@mesoporous silica-graphene oxide composites.

    Science.gov (United States)

    Wang, Yilong; Liang, Song; Chen, Bingdi; Guo, Fangfang; Yu, Shuili; Tang, Yulin

    2013-01-01

    The synergistic adsorption of heavy metal ions and humic acid can be very challenging. This is largely because of their competitive adsorption onto most adsorbent materials. Hierarchically structured composites containing polyethylenimine-modified magnetic mesoporous silica and graphene oxide (MMSP-GO) were here prepared to address this. Magnetic mesoporous silica microspheres were synthesized and functionalized with PEI molecules, providing many amine groups for chemical conjugation with the carboxyl groups on GO sheets and enhanced the affinity between the pollutants and the mesoporous silica. The features of the composites were characterized using TEM, SEM, TGA, DLS, and VSM measurements. Series adsorption results proved that this system was suitable for simultaneous and efficient removal of heavy metal ions and humic acid using MMSP-GO composites as adsorbents. The maximum adsorption capacities of MMSP-GO for Pb(II) and Cd (II) were 333 and 167 mg g(-1) caculated by Langmuir model, respectively. HA enhances adsorption of heavy metals by MMSP-GO composites due to their interactions in aqueous solutions. The underlying mechanism of synergistic adsorption of heavy metal ions and humic acid were discussed. MMSP-GO composites have shown promise for use as adsorbents in the simultaneous removal of heavy metals and humic acid in wastewater treatment processes.

  16. Efeito de diferentes processamentos sobre o teor de ácido ascórbico em suco de laranja utilizado na elaboração de bolo, pudim e geléia Effect of different processing methods on ascorbic acid content in orange juice used to make cakes, puddings and jelly

    Directory of Open Access Journals (Sweden)

    Patricia Teixeira da Silva

    2006-09-01

    Full Text Available Este estudo teve por objetivo avaliar a estabilidade do ácido ascórbico em suco de laranja cv. "Pêra" utilizado como ingrediente na elaboração de bolos, pudins e geléia. Os bolos e os pudins foram assados em forno convencional e de microondas, e a geléia foi elaborada em tacho aberto. Estas preparações foram submetidas a análises para determinação dos teores de ácido ascórbico e de sólidos solúveis totais, da acidez total titulável e do pH. Os teores de ácido ascórbico em bolos e pudins, quando comparados ao do suco de laranja in natura apresentaram redução de, respectivamente, 76,09% e 41,76%, quando assados em forno de microondas, e de 84,21% e 46,71%, quando assados em forno convencional. A geléia de laranja apresentou redução de 24,86% no teor de ácido ascórbico em relação ao suco de laranja in natura. A cocção de bolos e pudins realizada em forno de microondas proporcionou maior retenção do ácido ascórbico, quando comparada àquela realizada em forno convencional. Estas preparações apresentaram perda superior à da geléia, elaborada em tacho aberto. Foi observado, também, que os bolos perderam mais ácido ascórbico do que os pudins, em ambos os métodos de cocção avaliados.The aim of this study is to analyze the stability of ascorbic acid in orange juice cv. "Pera" used as an ingredient to prepare cakes, puddings and jelly. Cakes and puddings were baked in conventional and microwave ovens and the jelly was prepared in a pan without a lid. Ascorbic acid content, total soluble solids, total tritatable acidity and the pH were determined in all prepared foods. The AA content in cakes and puddings, when compared to the content of orange juice in natura had a reduction of 76.09% and 41.76%, respectively when baked in a microwave oven and of 84.21% and 46.71%, when baked in a conventional oven. Orange jelly showed a reduction of 24.76% in the ascorbic acid content related to orange juice in natura

  17. 9-CIS-RETINOIC ACID REPRESSES ESTROGEN-INDUCED EXPRESSION OF THE VERY-LOW-DENSITY APOLIPOPROTEIN-II GENE

    NARCIS (Netherlands)

    SCHIPPERS, IJ; KLOPPENBURG, M; SNIPPE, L; AB, G

    1994-01-01

    The chicken very low density apolipoprotein II (apoVLDLII) gene is estrogen-inducible and specifically expressed in liver. We examined the possible involvement of the retinoid X receptor (RXR) and its ligand 9-cis-retinoic acid (9-cis-RA) in the activation of the apoVLDLII promoter. We first concent

  18. Human acid alpha-glucosidase from rabbit milk has therapeutic effect in mice with glycogen storage disease type II

    NARCIS (Netherlands)

    A.G.A. Bijvoet (Agnes); A.J.J. Reuser (Arnold); H. van Hirtum (Hans); M.A. Kroos (Marian); E.H. van de Kamp; O. Schoneveld; P. Visser (Pim); J.P. Brakenhoff (Just); M. Weggeman; E.J.J.M. van Corven (Emiel); A.T. van der Ploeg (Ans)

    1999-01-01

    textabstractPompe's disease or glycogen storage disease type II (GSDII) belongs to the family of inherited lysosomal storage diseases. The underlying deficiency of acid alpha-glucosidase leads in different degrees of severity to glycogen storage in heart, skeletal and s

  19. Mitochondrial complex II participates in normoxic and hypoxic regulation of alpha-keto acids in the murine heart.

    NARCIS (Netherlands)

    Muhling, J.; Tiefenbach, M.; Lopez-Barneo, J.; Piruat, J.I.; Garcia-Flores, P.; Pfeil, U.; Gries, B.; Muhlfeld, C.; Weigand, M.A.; Kummer, W.; Weissmann, N.; Paddenberg, R.

    2010-01-01

    alpha-Keto acids (alpha-KAs) are not just metabolic intermediates but are also powerful modulators of different cellular pathways. Here, we tested the hypothesis that alpha-KA concentrations are regulated by complex II (succinate dehydrogenase=SDH), which represents an intersection between the

  20. Mitochondrial complex II participates in normoxic and hypoxic regulation of alpha-keto acids in the murine heart.

    NARCIS (Netherlands)

    Muhling, J.; Tiefenbach, M.; Lopez-Barneo, J.; Piruat, J.I.; Garcia-Flores, P.; Pfeil, U.; Gries, B.; Muhlfeld, C.; Weigand, M.A.; Kummer, W.; Weissmann, N.; Paddenberg, R.

    2010-01-01

    alpha-Keto acids (alpha-KAs) are not just metabolic intermediates but are also powerful modulators of different cellular pathways. Here, we tested the hypothesis that alpha-KA concentrations are regulated by complex II (succinate dehydrogenase=SDH), which represents an intersection between the mitoc

  1. 9-CIS-RETINOIC ACID REPRESSES ESTROGEN-INDUCED EXPRESSION OF THE VERY-LOW-DENSITY APOLIPOPROTEIN-II GENE

    NARCIS (Netherlands)

    SCHIPPERS, IJ; KLOPPENBURG, M; SNIPPE, L; AB, G

    1994-01-01

    The chicken very low density apolipoprotein II (apoVLDLII) gene is estrogen-inducible and specifically expressed in liver. We examined the possible involvement of the retinoid X receptor (RXR) and its ligand 9-cis-retinoic acid (9-cis-RA) in the activation of the apoVLDLII promoter. We first concent

  2. Purification and H-1 NMR spectroscopic characterization of phase II metabolites of tolfenamic acid

    DEFF Research Database (Denmark)

    Sidelmann, U. G.; Christiansen, E.; Krogh, L.

    1997-01-01

    )-anthranilic acid (T), N-(2-hydroxymethyl-3-chlorophenyl)-anthranilic acid (1), N-(2-hydroxymethyl-3-chloro-4-hydroxyphenyl)-anthranilic acid (2), N-(2-formyl-3-chlorophenyl) anthranilic acid (3), N-(2-methyl-3-chloro-4-hydroxyphenyl)-anthranilic acid (4), N-(2-methyl-3-chloro-5-hydroxyphenyl)-anthranilic acid (5...

  3. X-Ray Crystallographic Analysis, EPR Studies, and Computational Calculations of a Cu(II) Tetramic Acid Complex

    Science.gov (United States)

    Matiadis, Dimitrios; Tsironis, Dimitrios; Stefanou, Valentina; Igglessi–Markopoulou, Olga; McKee, Vickie; Sanakis, Yiannis; Lazarou, Katerina N.

    2017-01-01

    In this work we present a structural and spectroscopic analysis of a copper(II) N-acetyl-5-arylidene tetramic acid by using both experimental and computational techniques. The crystal structure of the Cu(II) complex was determined by single crystal X-ray diffraction and shows that the copper ion lies on a centre of symmetry, with each ligand ion coordinated to two copper ions, forming a 2D sheet. Moreover, the EPR spectroscopic properties of the Cu(II) tetramic acid complex were also explored and discussed. Finally, a computational approach was performed in order to obtain a detailed and precise insight of product structures and properties. It is hoped that this study can enrich the field of functional supramolecular systems, giving place to the formation of coordination-driven self-assembly architectures. PMID:28316540

  4. Type II fatty acid biosynthesis is essential for Plasmodium falciparum sporozoite development in the midgut of Anopheles mosquitoes.

    Science.gov (United States)

    van Schaijk, Ben C L; Kumar, T R Santha; Vos, Martijn W; Richman, Adam; van Gemert, Geert-Jan; Li, Tao; Eappen, Abraham G; Williamson, Kim C; Morahan, Belinda J; Fishbaugher, Matt; Kennedy, Mark; Camargo, Nelly; Khan, Shahid M; Janse, Chris J; Sim, Kim Lee; Hoffman, Stephen L; Kappe, Stefan H I; Sauerwein, Robert W; Fidock, David A; Vaughan, Ashley M

    2014-05-01

    The prodigious rate at which malaria parasites proliferate during asexual blood-stage replication, midgut sporozoite production, and intrahepatic development creates a substantial requirement for essential nutrients, including fatty acids that likely are necessary for parasite membrane formation. Plasmodium parasites obtain fatty acids either by scavenging from the vertebrate host and mosquito vector or by producing fatty acids de novo via the type two fatty acid biosynthesis pathway (FAS-II). Here, we study the FAS-II pathway in Plasmodium falciparum, the species responsible for the most lethal form of human malaria. Using antibodies, we find that the FAS-II enzyme FabI is expressed in mosquito midgut oocysts and sporozoites as well as liver-stage parasites but not during the blood stages. As expected, FabI colocalizes with the apicoplast-targeted acyl carrier protein, indicating that FabI functions in the apicoplast. We further analyze the FAS-II pathway in Plasmodium falciparum by assessing the functional consequences of deleting fabI and fabB/F. Targeted deletion or disruption of these genes in P. falciparum did not affect asexual blood-stage replication or the generation of midgut oocysts; however, subsequent sporozoite development was abolished. We conclude that the P. falciparum FAS-II pathway is essential for sporozoite development within the midgut oocyst. These findings reveal an important distinction from the rodent Plasmodium parasites P. berghei and P. yoelii, where the FAS-II pathway is known to be required for normal parasite progression through the liver stage but is not required for oocyst development in the Anopheles mosquito midgut.

  5. Preparation and characterization of ammonium-functionalized silica nanoparticle as a new adsorbent to remove methyl orange from aqueous solution

    Science.gov (United States)

    Liu, Jinshui; Ma, Shi; Zang, Lingjie

    2013-01-01

    Quaternary ammonium polyethylenimine (PEI) was successfully modified to silica nanoparticle (QPEI/SiO2) as a new adsorbent to remove methyl orange from aqueous solution. The isotherm and kinetics of dye adsorption were studied, which showed that Langmuir isotherm fit the experimental results well. The maximum adsorption capacity of QPEI/SiO2 for methyl orange is 105.4 mg/g. The equilibrium time for methyl orange adsorption onto QPEI/SiO2 was as short as 10 min, indicating that the adsorbent has a strong affinity for methyl orange. The adsorption capacities of the methyl orange are slightly influenced by the pH in the range of 3.2-9.6. The QPEI/SiO2 adsorbent can be used in the wide pH range, which is different from other adsorbent. This may attribute to the quaternary ammonium carrying positive charges in acidic and basic solution.

  6. Catalytic role of Cu(II) in the reduction of Cr(VI) by citric acid under an irradiation of simulated solar light.

    Science.gov (United States)

    Li, Ying; Chen, Cheng; Zhang, Jing; Lan, Yeqing

    2015-05-01

    The catalytic role of Cu(II) in the reduction of Cr(VI) by citric acid with simulated solar light was investigated. The results demonstrated that Cu(II) could significantly accelerate Cr(VI) reduction and the reaction obeyed to pseudo zero-order kinetics with respect to Cr(VI). The removal of Cr(VI) was related to the initial concentrations of Cu(II), citric acid, and the types of organic acids. The optimal removal of Cr(VI) was achieved at pH 4, and the rates of Cu(II) photocatalytic reduction of Cr(VI) by organic acids were in the order: tartaric acid (two α-OH groups, two -COOH groups)>citric acid (one α-OH group, three -COOH groups)>malic acid (one α-OH group, two -COOH groups)>lactic acid (one α-OH group, one -COOH group)≫succinic acid (two -COOH groups), suggesting that the number of α-OH was the key factor for the reaction, followed by the number of -COOH. The formation of Cu(II)-citric acid complex could generate Cu(I) and radicals through a pathway of metal-ligand-electron transfer, promoting the reduction of Cr(VI). This study is helpful to fully understanding the conversion of Cr(VI) in the existence of both organic acids and Cu(II) with solar light in aquatic environments.

  7. Direct and simultaneous spectrophotometric determination of Fe (III and Ni (II using salicylaldehyde acetoacetic acid hydrazone – Applications

    Directory of Open Access Journals (Sweden)

    V Srilalitha

    2010-12-01

    Full Text Available A rapid, simple and sensitive spectrophotometric method has been developed for determination of Fe (III and Ni (II using salicylaldehyde acetoacetic acid hydrazone (SAAH as a chromophoric reagent. The linear calibration ranges were obtained in each case. The proposed method is applied for the simultaneous determination of Fe (III and Ni (II utilizing their first order spectra. The method is based on the zero crossing measurement of first derivative amplitudes. The first derivative amplitudes at 525 nm and 395 nm obey Beer's law in the concentration range 0.054-0.270 μg/mL and 0.112-0.561 μg/mL for Fe (III and Ni (II respectively. A large number of foreign ions do not interfere in the present method. The method is used for the determination of micro amounts of Fe (III and Ni (II in alloy steels and in synthetic mixtures.

  8. Será que as laranjas e a cana-de-açúcar da Flórida azedam o livre comércio? uma análise de ratificação de nível II da política comercial dos Estados Unidos com o Brasil Do Florida oranges and sugarcane sour free trade? a level II ratification analysis of United States trade policy with Brasil

    Directory of Open Access Journals (Sweden)

    Mark Langevin

    2006-06-01

    Full Text Available O estado da Flórida e seus produtores de laranja e de cana-de-açúcar colocam-se no centro do palco das relações econômicas entre os Estados Unidos e o Brasil e do drama da Área de Livre Comércio das Américas (ALCA. Poderosos e persistentes, esses modestos interesses econômicos têm sua importância política amplificada pelo papel de pivô da Flórida nas recentes eleições presidenciais dos Estados Unidos. Aumentado pelo papel de pivô do estado no Colégio Eleitoral, os interesses dos setores de laranja e de cana-de-açúcar têm efetivamente restringido a autonomia do Executivo dos EUA. Este trabalho emprega a teoria de ratificação de acordos internacionais de Putnam e examina as contribuições de campanha dessas indústrias para explorar os desafios de ratificação de Nível II associado à influência política das principais forças protecionistas da Flórida. Este exame demonstra como os interesses faccionais e as instituições políticas podem se cruzar para ampliar a importância de indústrias com interesses estreitos e prescritos territorialmente, sob condições de alta incerteza eleitoral. Por fim, o artigo explora as implicações desses interesses inegociáveis sobre as relações EUA-Brasil e a política comercial brasileira.The state of Florida and its orange and sugarcane producers stand at the center-stage of United States - Brazil economic relations and the Free Trade in the Americas (FTAA drama. Powerful and persistent, the political importance of these modest economic interests is amplified by Florida's pivotal role in United States' presidential elections of late. Magnified by the the state's pivotal role in the Electoral College, Florida orange and sugarcane interests have effectively restricted the autonomy of the U.S. Executive. This paper employs Putnam's(1988 international agreement ratification theory and examines these industries campaign contributions to explore the Level II ratification challenges

  9. Investigation of irradiated rats DNA in the presence of Cu(II) chelates of amino acids Schiff bases.

    Science.gov (United States)

    Karapetyan, N H; Torosyan, A L; Malakyan, M; Bajinyan, S A; Haroutiunian, S G

    2016-01-01

    The new synthesized Cu(II) chelates of amino acids Schiff bases were studied as a potential radioprotectors. Male albino rats of Wistar strain were exposed to X-ray whole-body irradiation at 4.8 Gy. This dose caused 30% mortality of the animals (LD30). The survival of animals exposed to radiation after preliminary administration of 10 mg/kg Cu(II)(Nicotinyl-L-Tyrosinate)2 or Cu(II)(Nicotinyl-L-Tryptophanate)2 prior to irradiation was registered about 80 and 100% correspondingly. Using spectrophotometric melting and agarose gel electrophoresis methods, the differences between the DNA isolated from irradiated rats and rats pretreated with Cu(II) chelates were studied. The fragments of DNA with different breaks were revealed in DNA samples isolated from irradiated animals. While, the repair of the DNA structure was observed for animals pretreated with the Cu(II) chelates. The results suggested that pretreatment of the irradiated rats with Cu(II)(Nicotinyl-L-Tyrosinate)2 and Cu(II)(Nicotinyl-L-Tryptophanate)2 compounds improves the liver DNA characteristics.

  10. STRATEGI COPING ORANG TUA MENGHADAPI ANAK AUTIS

    Directory of Open Access Journals (Sweden)

    Desi Sulistyo Wardani

    2016-02-01

    Full Text Available Autis merupakan grey area dibidang kedokteran, yang artinya masih merupakan suatu hal yang penyebab, mekanisme, dan terapinya belum jelas benar. Permasalahan yang dihadapi oleh orang tua yang mempunyai anak autis ini memerlukan pemecahan sebagai upaya untuk beradaptasi terhadap masalah dari tekanan yang menimpa mereka. Konsep untuk memecahkan masalah ini disebut coping. Penelitian ini bertujuan untuk mengetahui orientasi strategi coping yang digunakan oleh orang tua untuk menghadapi anak penderita autis, bagaimana bentuk perilaku coping yang digunakan, dan apa dampak perilaku coping tersebut bagi orang tua. Subjek penelitian ini adalah orang tua yang mempunyai anak autis yang bersekolah di SD PLUS Harmony. Metode pengumpulan data yang digunakan adalah interview, sedangkan teknik analisis data yang digunakan adalah analisis induktif deskriptif. Hasil penelitian ini menunjukkan bahwa strategi coping pada orang tua yang mempunyai anak autis berorientasi pada penyelesaian masalah yang dihadapi (Problem Focused Coping, sedangkan bentuk perilaku coping yang muncul yaitu Instrumental Action yang termasuk dalam Problem Focused Coping dan Self-Controlling, Denial, dan Seeking Meaning yang termasuk dalam Emotion Focused Coping. Dampak positif dari perilaku coping yang dilakukan oleh orang tua yaitu Exercised Caution dan Seeking Meaning, sedangkan dampak negatif yang muncul diatasi orang tua dengan Intropersitive, Negotiation, dan Accepting Responbility.

  11. Doxycycline plus tauroursodeoxycholic acid for transthyretin amyloidosis: a phase II study.

    Science.gov (United States)

    Obici, Laura; Cortese, Andrea; Lozza, Alessandro; Lucchetti, J; Gobbi, Marco; Palladini, Giovanni; Perlini, Stefano; Saraiva, Maria J; Merlini, Giampaolo

    2012-06-01

    We designed a phase II, open-label study to evaluate the efficacy, tolerability, safety, and pharmacokinetics of orally doxycycline (100 mg BID) and tauroursodeoxycholic acid (TUDCA) (250 mg three times/day) administered continuously for 12 months. Primary endpoint is response rate defined as nonprogression of the neuropathy and of the cardiomyopathy. Since July 2010, we enrolled 20 patients. Seventeen patients have hereditary ATTR, two patients have senile systemic amyloidosis, and one is a domino recipient. Seven patients completed 12-month treatment, 10 completed 6-month treatment, two discontinued because of poor tolerability, and one is lost at follow-up. No serious adverse events were registered. No clinical progression of cardiac involvement was observed. The neuropathy (Neuropathy Impairment Score in the Lower Limbs [NIS-LL] and Kumamoto score) remained substantially stable over 1 year. These preliminary data indicate that the combination of Doxy-TUDCA stabilizes the disease for at least 1 year in the majority of patients with an acceptable toxicity profile.

  12. EFFECT OF NUTRITION ON CHEMICAL CHARACTERISTICS OF ORANGE FRUITS

    Directory of Open Access Journals (Sweden)

    Tarek FOUDA

    2014-12-01

    Full Text Available The aim of this study was to determine the chemical characterization of orange fruits using applications of nutrition minerals and growth substance during at private farm in wadi el-netron , ELbehari governorate, Egypt during in December2011. The results showed during maturity time increasing the total soluble solid (TSS, pH, percentage of liquid, (TSS/acidityand carotenoids while chlorophyll a, chlorophyll b and acidity were decreased.With one application of nutrition minerals and with growth substance were the lowest value of chlorophyll, a (chl,a and chlorophyll, b (chl,b as follow 0.42 and 0.45 (mg/100g while with control management were the highest value to total soluble solid (Tss and carotenoids (car. as follow 10.07(Brix,% and 15.77 (mg/100g. The pattern of changes was clearly observed from the absorption spectra of the green and orange When orange is fully ripe, chlorophyll would be greatly reduced or may disappear completely and carotenoids becomes the dominant pigment in the fruit surface.

  13. Pectinesterases from the orange fruit : their purefaction, general characteristics and juice cloud destabilizing properties

    NARCIS (Netherlands)

    Versteeg, C.

    1979-01-01

    Twelve forms of pectinesterase were detected in citrus fruits. Two forms, representing over 90% of the total pectinesterase activity in Navel oranges, were purified. These pectinesterases, named Pectinesterase I and II have isoelectric points of 10.05 and>11.0, respectively. Both pectinesterases hav

  14. Pectinesterases from the orange fruit : their purification, general characteristics and juice cloud destabilizing properties

    NARCIS (Netherlands)

    Versteeg, C.

    1979-01-01

    Twelve forms of pectinesterase were detected in citrus fruits. Two forms, representing over 90% of the total pectinesterase activity in Navel oranges, were purified. These pectinesterases, named Pectinesterase I and II have isoelectric points of 10.05 and>11.0, respectively. Both pectinesterases

  15. A K-12 Articulation Model for the Orange Unified School District.

    Science.gov (United States)

    Joseph, Louie S.

    This Maxi II practicum documents the development of a model articulation process and the implementation of that process in the Orange (California) Unified School District. The model was intended to improve the continuity of student progression through the grades from elementary to junior high to senior high school. Primary concerns of the…

  16. Spectroscopic study of Mg(II) ion influence on the autoxidation of gallic acid in weakly alkaline aqueous solutions

    Science.gov (United States)

    Nikolić, G. M.; Veselinović, A. M.; Nikolić, R. S.; Mitić, S. S.

    2011-12-01

    Gallic acid autoxidation in weakly alkaline aqueous solutions was studied by UV-Vis spectrophotometry and ESR spectroscopy under various conditions. Lowering the pH value from 10 to 8.5 probably changes the mechanism of the autoxidation reaction as evidenced by the different time variations of UV-Vis spectra of solutions. The presence of Mg(II) ions greatly influences the autoxidation reaction at pH 8.5. Although the UV-Vis spectral changes with time follow the similar pattern during the gallic acid autoxidation at pH 10 and at pH 8.5 in the presence of Mg(II) ions, some small differences indicate that Mg(II) ions not only affect the electron density of absorbing species but also influence the overall mechanism of the autoxidation reaction. ESR spectra of free radials formed during the initial stage of gallic acid autoxidation at pH 8.5 in the presence of Mg(II) ions were recorded. Computer simulation of ESR spectra allows partial characterization of these free radicals.

  17. SYNTHESIS, CHARACTERIZATION AND ANTITUMOR ACTIVITY OF A Ca (II COORDINATION POLYMER BASED ON 3-AMINO-2-PYRAZINECARBOXYLIC ACID

    Directory of Open Access Journals (Sweden)

    XI-SHI TAI

    2015-10-01

    Full Text Available A new Ca(II coordination polymer has been obtained by reaction of Ca(ClO42·H2O with 3-amino-2-pyrazinecarboxylic acid in CH3CH2OH/H2O. It was characterized by IR, 1HNMR, thermal analysis and X-ray single crystal diffraction analysis. X-ray analysis reveals that each Ca(II center is seven-coordination with a N2O5 distorted pentagonal bipyramidal coordination environment. The Ca(II ions are linked through the O atoms of 3-amino-2-pyrazinecarboxylic acid ligands to form 1D chain structure. And then a 3D network structure is constructed by hydrogen bonds and π-π stacking. The antitumor activity of 3-amino-2-pyrazinecarboxylic acid ligand and its Ca(II coordination polymer against human intestinal adenocarcinoma HCT-8 cells, lung adenocarcinoma HCT-116 cells and human lung adenocarcinoma A549 cells line have been investigated.

  18. 超高效液相色谱法检测西红花中非法添加的染料金橙Ⅱ%QualitatiVe and Quantitative Determinaion of Illegally Added Acid Orange Ⅱ in Croci Stigma by UPLC

    Institute of Scientific and Technical Information of China (English)

    胡晓炜

    2011-01-01

    目的 建立检测中药西红花中非法添加的金橙Ⅱ的液质联用鉴别法和超高效液相色谱含量测定法.方法 用超高效液相色谱法分离中药西红花中非法添加的金橙Ⅱ,用离子阱进行定性鉴别,流动相为乙腈-0.01 mol/L醋酸铵溶液(30:70),离子化模式为ESI(+),碰撞能量为30 V;用超高效液相色谱法测定金橙Ⅱ含量,流动相为乙腈-0.0l mol/L醋酸铵溶液(30:70),检测波长484 nm.结果 在拟订的质谱条件下,金橙Ⅱ产生[M+H-Na]+分子离子峰,二级质谱的特征碎片离子明显;定量检测方面,进样量与峰面积的线性范围为5.435~745.0 ng,r=0.999 0,平均加样回收率为98.29%,RSD为1.25%(n=5).结论 液质联用法定性准确、可靠,液相色谱含量测定法简便、快速、准确.%Objective To establish an identification method of LC -MS/MS and a quantification method of ultra performance liquid chromatography - mass spectrometry(UPLC - MS/MS) for determining illegally added acid orange Ⅱin Croci Stigma. Methods Illegally added acid orange Ⅱ in Croci Stigma was separated by UPLC and the qualitative identification was performed by ion trap. The mobile phase was consisted of acetonitrile -0. 01 mol/L ammonium acetate (30 ∶ 70). The ionization mode was ESI(+ ) and MS/MS collision energy was 30 V. Then, the content of acid orange Ⅱwas determined by UPLC with the mobile phase of acetonitrile -O.Olmol/L ammomum acetate (30 ∶70) and the detection wavelength was 484 nm. Results Under the experimental condition of mass spectrum. acid orange Ⅱ produced the [M+H - Na] + molecular ion peaks and apparently revealed the characteristic fragment ion of second order mass spectrum. In the quantitative determination, the linearity between the sample size and the peak area was over the range of 5. 435 -745. 0 ng, r=0. 999 0. The average recovery rate was 98. 29% , RSD was 1. 25% ( n =5). Conclusion The LC -MS/MS method is accurate and fast for the

  19. Nitrilotriacetic acid functionalized Adansonia digitata biosorbent: Preparation, characterization and sorption of Pb (II) and Cu (II) pollutants from aqueous solution

    OpenAIRE

    Adewale Adewuyi; Fabiano Vargas Pereira

    2016-01-01

    Nitrilotriacetic acid functionalized Adansonia digitata (NFAD) biosorbent has been synthesized using a simple and novel method. NFAD was characterized by X-ray Diffraction analysis technique (XRD), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analyzer, Fourier Transform Infrared spectrometer (FTIR), particle size dispersion, zeta potential, elemental analysis (CHNS/O analyzer), thermogravimetric analysis (TGA), differential thermal analysis (DTA), derivative t...

  20. Synthesis, Characterization and Thermal Analysis of a New Acetic Acid (2-Hydroxy-benzylidene-hydrazide and its Complexes with Hg(II and Pd(II

    Directory of Open Access Journals (Sweden)

    Hajar Sahebalzamani

    2011-01-01

    Full Text Available The new complexes have been synthesized by the reaction of Hg(II and Pd(II with acetic acid(2-hydroxy-benzylidene- hydrazide (L. These new complexes were characterized by elemental analysis, IR, H NMR spectroscopy and UV spectral techniques. The changes observed between the FT-IR, H NMR and UV-Vis spectra of the ligands and of the complexes allowed us to establish the coordination mode of the metal in complexes. Thermal properties, TG-DTA of these complexes were studied. TG- DTA and other analytical methods have been applied to the investigation of the thermal behavior and structure of the compounds [M(L2]Cl2 M= Hg, Pd. Thermal decomposition of these compounds is multi-stage processes.

  1. Mini-Orange Spectrometer at CIAE

    CERN Document Server

    Zheng, Yun; Li, Guang-Sheng; Li, Cong-Bo; He, Chuang-Ye; Chen, Qi-Ming; Zhong, Jian; Zhou, Wen-Kui; Deng, Li-Tao; Zhu, Bao-Ji

    2016-01-01

    A Mini-Orange spectrometer used for in-beam measurements of internal conversion electrons, which consists of a Si(Li) detector and different sets of SmO$_5$ permanent magnets for filtering and transporting the conversion electrons to the Si(Li) detector, has been developed at China Institute of Atomic Energy. The working principle and configuration of the Mini-Orange spectrometer are described. The performance of the setup is illustrated by measured singles conversion electron spectra using the Mini-Orange spectrometer.

  2. Variação da concentração de vitamina C, ºBrix e acidez em néctar de laranja em embalagens cartonadas = Modification of vitamin C concentration, Brix and acidity in orange nectar in aseptic packaging

    Directory of Open Access Journals (Sweden)

    Telma Lucia de Oliveira

    2007-07-01

    Full Text Available Amostras de néctar de laranja, acondicionadas em embalagens cartonadas, foram armazenadas em local climatizado (25°C e em refrigerador (4°C. Durante oito semanas, análises de vitamina C, Brix e acidez foram realizadas no momento da abertura daembalagem, e seu produto residual foi ainda analisado durante quatro dias de estocagem em refrigerador. Analisando-se os resultados das variáveis por métodos estatísticos, observou-se que a temperatura de armazenagem influencia a quantidade de vitamina C do néctar delaranja. Ocorre decréscimo significativo na concentração de vitamina C, mas não há influência da temperatura de armazenagem no Brix e acidez do produto. O tempo de armazenamento influencia vitamina C, Brix e acidez. Constata-se, ainda, que após oito semanas de estocagem e quatro dias de abertura da embalagem a quantidade de vitamina C,em um copo de 200 mL do néctar de laranja estudado, supre a necessidade média diária de um adulto (60 mg.Samples of orange nectar in aseptic packaging were stored incontrolled room temperature (25°C and in a refrigerator (4°C. For eight weeks, analyses of vitamin C, Brix and acidity were conducted as the packages were opened, and their residual products were further analyzed during a period of four days stored in a refrigerator.By using statistical models from the results found, it was concluded that storage temperature influences the quantity of vitamin C in orange nectar. There was a significant decrease in vitamin C concentration in nectar, but storage temperature does not influenceacidity or Brix. Storage time does influence vitamin C, Brix and acidity. It was concluded that after eight weeks of storage and four days of opening the package, the amount of vitamin C in a 200 mL glass of orange nectar is enough to supply the average needed dailyintake (60 mg of vitamin C for an adult.

  3. Comparison of phenolic compounds of orange juice processed by pulsed electric fields (PEF) and conventional thermal pasteurisation.

    Science.gov (United States)

    Agcam, E; Akyıldız, A; Akdemir Evrendilek, G

    2014-01-15

    Processing of orange juice by pulsed electric fields (PEF) and thermal pasteurisation was carried out to compare changes in total phenolic concentration, hydroxybenzoic acid, hydroxycinnamic acids, flavonols, flavones and flavonones before and after being stored at 4°C for 180days. Changes in the initial total phenolic concentration of the samples varied depending on the applied electric field intensity and thermal pasteurisation. Hesperidin and chlorogenic acids were detected as the most abounded flavonoid and phenolic acids in the orange juice, respectively. Except for syringic acid and neoeriocitrin, the concentration of the phenolic compounds indentified in the orange juice samples enhanced after the PEF or thermal pasteurisation. The samples treated with PEF had more stable flavonoids and phenolic acids than those treated with the thermal pasteurisation. The PEF-treated samples had higher sensory scores than the heat-treated samples.

  4. Aspartic acid interaction with cobalt(II) in dilute aqueous solution: A 57Co emission Mössbauer spectroscopic study

    Science.gov (United States)

    Kamnev, Alexander A.; Tugarova, Anna V.; Kovács, Krisztina; Homonnay, Zoltan; Kuzmann, Erno; Vértes, Attila

    2012-03-01

    Emission (57Co) Mössbauer spectra of the aspartic acid—57CoCl2 system were measured at T = 80 K in frozen aqueous solution and in the form of a dried residue of this solution. The Mössbauer spectra, besides a weak contribution from after-effects, showed two Fe2 + /Co2 + components which were ascribed to octahedrally and tetrahedrally coordinated 57CoII microenvironments in the Asp-cobalt(II) complex. This dual coordination mode may be due to the involvement of the second terminal carboxylic group of aspartic acid in the coordination sphere of Co.

  5. Catalytic Mechanism and Efficiency of Methane Oxidation by Hg(II) in Sulfuric Acid and Comparison to Radical Initiated Conditions

    OpenAIRE

    Fuller, Jack T.; Butler, Steven; Devarajan, Deepa; Jacobs, Austin; Hashiguchi, Brian G.; Konnick, Michael M.; Goddard, William A.; Gonzales, Jason M.; Periana, Roy A.; Ess, Daniel H.

    2016-01-01

    Methane conversion to methyl bisulfate by Hg^(II)(SO_4) in sulfuric acid is an example of fast and selective alkane oxidation catalysis. Dichotomous mechanisms involving C–H activation and electron transfer have been proposed based on experiments. Radical oxidation pathways have also been proposed for some reaction conditions. Hg^(II) is also of significant interest because as a d^(10) transition metal it is similar to d^(10) main-group metals that also oxidize alkanes. Density-functional cal...

  6. Acid-tolerant microaerophilic Fe(II)-oxidizing bacteria promote Fe(III)-accumulation in a fen.

    Science.gov (United States)

    Lüdecke, Claudia; Reiche, Marco; Eusterhues, Karin; Nietzsche, Sandor; Küsel, Kirsten

    2010-10-01

    The ecological importance of Fe(II)-oxidizing bacteria (FeOB) at circumneutral pH is often masked in the presence of O(2) where rapid chemical oxidation of Fe(II) predominates. This study addresses the abundance, diversity and activity of microaerophilic FeOB in an acidic fen (pH ∼ 5) located in northern Bavaria, Germany. Mean O(2) penetration depth reached 16 cm where the highest dissolved Fe(II) concentrations (up to 140 µM) were present in soil water. Acid-tolerant FeOB cultivated in gradient tubes were most abundant (10(6) cells g(-1) peat) at the 10-20 cm depth interval. A stable enrichment culture was active at up to 29% O(2) saturation and Fe(III) accumulated 1.6 times faster than in abiotic controls. An acid-tolerant, microaerophilic isolate (strain CL21) was obtained which was closely related to the neutrophilic, lithoautotrophic FeOB Sideroxydans lithotrophicus strain LD-1. CL21 oxidized Fe(II) between pH 4 and 6.0, and produced nanoscale-goethites with a clearly lower mean coherence length (7 nm) perpendicular to the (110) plane than those formed abiotically (10 nm). Our results suggest that an acid-tolerant population of FeOB is thriving at redox interfaces formed by diffusion-limited O(2) transport in acidic peatlands. Furthermore, this well-adapted population is successfully competing with chemical oxidation and thereby playing an important role in the microbial iron cycle.

  7. THE COORDINATION COMPOUNDS OF COBALT (II, III WITH DITHIOCARBAMIC ACID DERIVATIVES — MODIFICATORS OF HYDROLYTIC ENZYMES ACTIVITY

    Directory of Open Access Journals (Sweden)

    L. D. Varbanets

    2013-02-01

    Full Text Available Chloride, bromide and isothiocyanate complexes of cobalt(II with N-substituted thiocarbamoyl-N?-pentamethylenesulfenamides (1–(12, and also complexes of cobalt(II, Ш with derivatives of morpholine-4-carbodithioic acid (13–(18 have been used as modificators of enzymes of hydrolytic action — Bacillus thurin-giensis ІМВ В-7324 peptidases, Bacillus subtilis 147 and Aspergillus flavus var. oryzae 80428 amylases, Eupenicillium erubescens 248 and Cryptococcus albidus 1001 rhamnosidases. It was shown that cobalt (II, Ш compounds influence differently on the activity of enzymes tested, exerted both inhibitory and stimulatory action. It gives a possibility to expect that manifestation of activity by complex molecule depends on ligand and anion presence — Cl–, Br– or NCS–. The high activating action of cobalt(II complexes with N-substituted thiocarbamoyl-N?-pentamethylenesulphenamides (1–(12 on elastase and fibrinolytic activity of peptidases compared to tris(4-morpholinecarbodithioatocobalt(ІІІ (14 and products of its interaction with halogens (15–(17, causes inhibitory effect that is probably due to presence of a weekly S–N link, which is easy subjected to homolytic breaking. The studies of influences of cobalt(II complexes on activity of C. аlbidus and E. еrubescens ?-Lrhamnosidases showed, that majority of compounds inhibits of its activity, at that the most inhibitory effect exerts to C. аlbidus enzyme.To sum up, it is possible to state that character of influence of cobalt(II complexes with N-substituted thiocarbamoyl-N?-pentamethylenesulphenamides, and also cobalt(II, Ш complexes with derivatives of morpholine-4-carbodithioic acid varies depending on both strain producer and enzyme tested. The difference in complex effects on enzymes tested are due to peculiarities of building and functional groups of their active centers, which are also responsible for binding with modificators.

  8. Cytotoxicity of copper(II)-complexes with some S-alkyl derivatives of thiosalicylic acid. Crystal structure of the binuclear copper(II)-complex with S-ethyl derivative of thiosalicylic acid

    Science.gov (United States)

    Nikolić, Miloš V.; Mijajlović, Marina Ž.; Jevtić, Verica V.; Ratković, Zoran R.; Novaković, Slađana B.; Bogdanović, Goran A.; Milovanović, Jelena; Arsenijević, Aleksandar; Stojanović, Bojana; Trifunović, Srećko R.; Radić, Gordana P.

    2016-07-01

    The spectroscopically predicted structure of the obtained copper(II)-complex with S-ethyl derivative of thiosalicylic acid was confirmed by X-ray structural study and compared to previously reported crystal structure of the Cu complex with S-methyl derivative. Single crystals suitable for X-ray measurements were obtained by slow crystallization from a water solution. Cytotoxic effects of S-alkyl (R = benzyl (L1), methyl (L2), ethyl (L3), propyl (L4) and butyl (L5)) derivatives of thiosalicylic acid and the corresponding binuclear copper(II)-complexes on murine colon carcinoma cell lines, CT26 and CT26.CL25 and human colon carcinoma cell line HCT-116 were reported here. The analysis of cancer cell viability showed that all the tested complexes had low cytotoxic effect on murine colon carcinoma cell lines, but several times higher cytotoxicity on normal human colon carcinoma cells.

  9. 21 CFR 146.137 - Frozen orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen orange juice. 146.137 Section 146.137 Food... HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.137 Frozen orange juice. (a) Frozen orange juice is orange juice as defined in § 146.135...

  10. 21 CFR 146.145 - Orange juice from concentrate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Orange juice from concentrate. 146.145 Section 146... Juices and Beverages § 146.145 Orange juice from concentrate. (a) Orange juice from concentrate is the food prepared by mixing water with frozen concentrated orange juice as defined in § 146.146 or...

  11. Kinetics of the oxidative hydroxylation of tetraphosphorus in the presence of copper(II chloride modified by humic (fulvo- acid

    Directory of Open Access Journals (Sweden)

    Zhaksyntay Kairbekov

    2012-12-01

    Full Text Available It was established that in mild conditions (50-70 oC, РО2= 1 atm white phosphorus effectively is oxidized by oxygen in water-toluene solutions of copper(II chloride modified by humic (fulvo- acid to give mainly phosphoric acid. Humic (fulvo- acid was extracted from brown coal of domestic deposit Kiyakty. For determination of optimum parameters of fulvo-acid extraction the laboratory experiments were carried out using the method of experiment planning. The kinetics, intermediate and final products, optimum conditions of new catalytic reaction of P4 oxidation by oxygen in water medium were defined by kinetics, volumometry, redox-potentiometry, 31Р{1Н} NMR spectroscopy and  titration. 

  12. Clinical evaluation of Moro (Citrus sinensis (L.) Osbeck) orange juice supplementation for the weight management.

    Science.gov (United States)

    Cardile, Venera; Graziano, Adriana Carol Eleonora; Venditti, Alessandro

    2015-01-01

    In the last years, several studies have recently evaluated the beneficial effects of red orange juice (Citrus sinensis (L.) Osbeck) and its active components in weight management and obesity. Moro orange is a cultivar of red orange, particularly rich in active compounds such as anthocyanins, hydroxycinnamic acids, flavone glycosides and ascorbic acid, which displays anti-obesity effects in in vitro and in vivo studies. In this clinical study, the effect of a Moro juice extract (Morosil(®), 400 mg/die) supplementation was evaluated in overweight healthy human volunteers for 12 weeks. Results showed that Moro juice extract intake was able to induce a significant reduction in body mass index (BMI) after 4 weeks of treatment (p juice have a synergistic effect on fat accumulation in humans and Moro juice extract can be used in weight management and in the prevention of human obesity.

  13. Mexican Fan Palm - Orange Co. [ds350

    Data.gov (United States)

    California Department of Resources — This dataset provides the known distribution of Mexican fan palm (Washingtonia robusta) in southern Orange County. The surveys were conducted from May to June, 2007...

  14. Arundo Distribution - Orange Co. [ds348

    Data.gov (United States)

    California Department of Resources — This dataset provides the known distribution of Arundo (Arundo donax) in southern Orange County. The surveys were conducted from May to June, 2007 and were funded by...

  15. Pampas Grass - Orange Co. [ds351

    Data.gov (United States)

    California Department of Resources — This dataset provides the known distribution of pampas grass (Cortaderia selloana) in southern Orange County. The surveys were conducted from May to June, 2007 and...

  16. The Orange Juice Distribution Channel: Some Characteristics ...

    African Journals Online (AJOL)

    PROMOTING ACCESS TO AFRICAN RESEARCH ... in retailing and also in the FCOJ (Frozen Concentrated Orange Juice) supply. These changes are threatening and also bringing opportunities to companies. This paper has two objectives.

  17. Biogenic glutamic acid-based resin: Its synthesis and application in the removal of cobalt(II)

    Energy Technology Data Exchange (ETDEWEB)

    Jamiu, Zakariyah A.; Saleh, Tawfik A.; Ali, Shaikh A., E-mail: shaikh@kfupm.edu.sa

    2017-04-05

    Highlights: • A novel resin embedded with metal chelating glutamic acid was synthesized. • The biogenic amino acid residues imparted remarkable efficacy to remove Co(II). • The resin showed excellent ability to remove various metals from wastewater. - Abstract: Inexpensive biogenic glutamic acid has been utilized to synthesize a cross-linked dianionic polyelectrolyte (CDAP) containing metal chelating ligands. Cycloterpolymerization, using azoisobutyronitrile as an initiator, of N,N-diallylglutamic acid hydrochloride, sulfur dioxide and a cross-linker afforded a pH-responsive cross-linked polyzwitterionic acid (CPZA) which upon basification with NaOH was converted into CDAP. The new resin, characterized by a multitude of spectroscopic techniques as well as Scanning Electron Microscopy (SEM) and Brunauer–Emmett–Teller (BET) analyses, was evaluated for the removal of Co(II) as a model case under different conditions. The adsorption capacity of 137 mg g{sup −1} does indeed make the resin as one of the most effective sorbents in recent times. The resin leverages its cheap natural source and ease of regeneration in combination with its high and fast uptake capacities to offer a great promise for wastewater treatment. The resin has demonstrated remarkable efficiency in removing toxic metal ions including arsenic from a wastewater sample.

  18. VIABILIDADE DO PÓLEN EM VARIEDADES DE LARANJA DOCE POLLEN VIABILITY IN SWEET ORANGE VARIETIES

    Directory of Open Access Journals (Sweden)

    Edson Tobias Domingues

    1999-01-01

    sexual hybridization, but on the other hand, it has economic importance in leading to fewer seeds per fruit in some citrus varieties. In order to characterize 44 sweet orange varieties (Citrus sinensis [L.] osbeck for pollen viability, anthers were collected from the varieties grafted on Cleopatra mandarin. The varieties investigated represented the major sweet orange groups: acidic oranges (as 'Pera' orange, low acidic oranges (as 'Lima' orange, navel oranges (as 'Bahia' orange and bloody oranges (as 'Rubi Blood' orange. The percent of viable pollen was evaluated using acetic carmine stain under optic microscopy. The values ranged from 12.0% for 'Pera Sem Sementes' orange to 88.8% for 'Hamlin Reserva' orange. The 'Hamlin' clones showed the largest percent of viable pollen. Absence of pollen in navel oranges, originated from 'Bahia' variety was observed. The varieties 'Pera', 'Valência' and 'Natal', which are the main sweet orange cultivars in São Paulo State and Brazil, presented low percent of viable pollen.

  19. Herbicide Orange Site Characterization Study, Eglin AFB

    Science.gov (United States)

    1987-01-01

    SCFILE cue ESL-TR-86-22 HERBICIDE ORANGE SITE CHARACTERIZATION STUDY EGLIN AFB 10 A.B. CROCKETT, A. PROPP , T. KIMES EG&G IDAHO, INC O I P.O. BOX...Orange Site Characterization Study.4lin AFB 12- PERSONAL AIITHOS(S) Crockett, A.B. , Propp , A., Kinies T. / \\ 4 Final FROM APX 84/TO Sen 86 1 ... I

  20. Pengenalan Gangguan Depresif Pada Orang Usia Lanjut

    OpenAIRE

    Bongsoe, Syamsir

    2008-01-01

    Pada orang usia lanjut, gangguan depresif merupakan suasana alam perasaan yang utama bagi orang usia lanjut dengan penyakit fisik kronik dan kerusakan fungsi kognitif yang disebabkan oleh adanya penderitaan, disabilitas, perhatian keluarga yang kurang serta bertambah buruknya penyakit fisik yang banyak dialaminya. Selain itu proses-proses sehubungan dengan ketuaan dan penyakit fisik yang dialaminya akan mempengaruhi jalur frontostriatal, amygdala serta hypocampus, dan meningkatkan kerentanan ...

  1. Lysophosphatidic Acid Up-Regulates Hexokinase II and Glycolysis to Promote Proliferation of Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Abir Mukherjee

    2015-09-01

    Full Text Available Lysophosphatidic acid (LPA, a blood-borne lipid mediator, is present in elevated concentrations in ascites of ovarian cancer patients and other malignant effusions. LPA is a potent mitogen in cancer cells. The mechanism linking LPA signal to cancer cell proliferation is not well understood. Little is known about whether LPA affects glucose metabolism to accommodate rapid proliferation of cancer cells. Here we describe that in ovarian cancer cells, LPA enhances glycolytic rate and lactate efflux. A real time PCR-based miniarray showed that hexokinase II (HK2 was the most dramatically induced glycolytic gene to promote glycolysis in LPA-treated cells. Analysis of the human HK2 gene promoter identified the sterol regulatory element-binding protein as the primary mediator of LPA-induced HK2 transcription. The effects of LPA on HK2 and glycolysis rely on LPA2, an LPA receptor subtype overexpressed in ovarian cancer and many other malignancies. We further examined the general role of growth factor-induced glycolysis in cell proliferation. Like LPA, epidermal growth factor (EGF elicited robust glycolytic and proliferative responses in ovarian cancer cells. Insulin-like growth factor 1 (IGF-1 and insulin, however, potently stimulated cell proliferation but only modestly induced glycolysis. Consistent with their differential effects on glycolysis, LPA and EGF-dependent cell proliferation was highly sensitive to glycolytic inhibition while the growth-promoting effect of IGF-1 or insulin was more resistant. These results indicate that LPA- and EGF-induced cell proliferation selectively involves up-regulation of HK2 and glycolytic metabolism. The work is the first to implicate LPA signaling in promotion of glucose metabolism in cancer cells.

  2. Identification of different coordination geometries by XAFS in copper(II) complexes with trimesic acid

    Science.gov (United States)

    Gaur, A.; Klysubun, W.; Soni, Balram; Shrivastava, B. D.; Prasad, J.; Srivastava, K.

    2016-10-01

    X-ray absorption spectroscopy (XAS) is very useful in revealing the information about geometric and electronic structure of a transition-metal absorber and thus commonly used for determination of metal-ligand coordination. But XAFS analysis becomes difficult if differently coordinated metal centers are present in a system. In the present investigation, existence of distinct coordination geometries around metal centres have been studied by XAFS in a series of trimesic acid Cu(II) complexes. The complexes studied are: Cu3(tma)2(im)6 8H2O (1), Cu3(tma)2(mim)6 17H2O (2), Cu3(tma)2(tmen)3 8.5H2O (3), Cu3(tma) (pmd)3 6H2O (ClO4)3 (4) and Cu3(tma)2 3H2O (5). These complexes have not only Cu metal centres with different coordination but in complexes 1-3, there are multiple coordination geometries present around Cu centres. Using XANES spectra, different coordination geometries present in these complexes have been identified. The variation observed in the pre-edge features and edge features have been correlated with the distortion of the specific coordination environment around Cu centres in the complexes. XANES spectra have been calculated for the distinct metal centres present in the complexes by employing ab-initio calculations. These individual spectra have been used to resolve the spectral contribution of the Cu centres to the particular XANES features exhibited by the experimental spectra of the multinuclear complexes. Also, the variation in the 4p density of states have been calculated for the different Cu centres and then correlated with the features originated from corresponding coordination of Cu. Thus, these spectral features have been successfully utilized to detect the presence of the discrete metal centres in a system. The inferences about the coordination geometry have been supported by EXAFS analysis which has been used to determine the structural parameters for these complexes.

  3. Comparative NH 3-sensing characteristic studies of PANI/TiO II nanocomposite thin films doped with different acids

    Science.gov (United States)

    Tai, Huiling; Jiang, Yadong; Xie, Guangzhong; Yu, Junsheng; Ying, Zhihua; Chen, Xuan

    2008-02-01

    Polyaniline/titanium dioxide (PANI/TiO II) nanocomposite thin films were synthesized by in-situ self-assembly method, which were doped with p-toluene sulphonic acid (p-TSA) and hydrochloric acid (HCl), respectively. The thin films were characterized by using UV-Vis absorption spectroscopy and scanning electron microscope (SEM), and the NH 3 gas sensitive properties of the thin films were investigated at room temperature. The results showed that the PANI/TiO II thin film doped with HCl was superior to that doped with p-TSA in terms of response-recovery characteristics. The surface morphology characterization of the thin films were performed to explain the different gas-sensing properties.

  4. ORANGE JUICE AND BLOOD PRESSURE

    Directory of Open Access Journals (Sweden)

    M. F. VALIM

    2009-01-01

    Full Text Available

    Blood pressure is the force of blood against artery walls. It is measured in millimeters of mercury (mm Hg and recorded as two numbers: systolic pressure (as the heart contracts over diastolic pressure (as the heart relaxes between beats. High blood pressure (hypertension is defined as chronically elevated high blood pressure, with systolic blood pressure (SBP of 140 mm Hg or greater, and diastolic blood pressure (DBP of 90 mm Hg or greater. High blood pressure (HBP, smoking, abnormal blood lipid levels, obesity and diabetes are risk factors for coronary heart disease, the leading cause of death in the US. Lifestyle modifications such as engaging in regular physical activity, quitting smoking and eating a healthy diet (limiting intake of saturated fat and sodium and increasing consumption of fiber, fruits and vegetables are advocated for the prevention, treatment, and control of HBP. As multiple factors influence blood pressure, the effects of each factor are typically modest, particularly in normotensive subjects, yet the combined effects can be substantial. Nutrition plays an important role in influencing blood pressure. Orange juice should be included as part of any low sodium diet and/or any blood pressure reducing eating plan, as it is sodium free, fat-free and can help meet recommended levels of potassium intake that may contribute to lower BP.

  5. Antimatter, clockwork orange, laser divestment

    Science.gov (United States)

    Asmus, John F.

    2005-06-01

    In 1972 Ente Nazionale Idrocarburi sponsored a program to holographically record the images of Venetian sculptural treasures for archival purposes. At Laboratorio San Gregorio, where the initial holography took place, G. Musumeci and K. Hempel suggested an experiment to determine whether the concentrated beam from the ruby holographic laser could ablate black-patina crusts from decaying marble. Initial success of a laser-divestment test on a Palazzo Ducale capital launched a search for funding to enable a full-scale laser-conservation demonstration. Later, at a Caltech reunion one of the author's physics professors (Carl Anderson, the discoverer of mu mesons and the positron), noting the prominence of the Venice Film Festival suggested our approaching the motion picture industry. Many years earlier Anderson's Caltech classmate, Frank Capra, had supported the research that led to the discovery of cosmic-ray-generated antimatter on Pikes Peak. (After Caltech, Capra had become a director at Columbia Studios.) Anderson's chance comment led to an introduction to producer Jack Warner at a festival screening of his "A Clockwork Orange" in Asolo. He and his friends contributed US$5000 toward the laser conservation of a marble relief of "The Last Supper" in the Porta della Carta of Venice. This work was conducted in 1980 under the direction of Arch. G. Calcagno. In 1981 it was found that the granite veneer or the newly completed Warner Center Tower had been stained during transit from the quarry. The Venice laser successfully restored the veneer, thereby returning the Warner Brothers' favor.

  6. Preparation and characterization of trihydroxamic acid functionalized carbon materials for the removal of Cu(II) ions from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Godino-Salido, M. Luz, E-mail: mlgodino@ujaen.es [Departamento de Química Inorgánica y Orgánica, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071, Jaén (Spain); Santiago-Medina, Antonio; López-Garzón, Rafael; Gutiérrez-Valero, María D.; Arranz-Mascarós, Paloma; López de la Torre, M. Dolores [Departamento de Química Inorgánica y Orgánica, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071, Jaén (Spain); Domingo-García, María; López-Garzón, F. Javier [Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Granada, 18071, Granada (Spain)

    2016-11-30

    Highlights: • Hybrid materials made by irreversible adsorption of a deferoxamine derivative on ACs. • The surface trihydroxamate groups are the active functions of the hybrid materials. • Great adsorption capacity for Cu(II) of novel trihydroxamic acid functionalized ACs. • Desorption of Cu(II) from the loaded hybrid materials regenerates the parent hybrids. - Abstract: The main objective of this study is to prepare and characterize two functionalizated carbon materials with enhanced adsorptive properties for Cu(II). Thus, two novel hybrid materials have been prepared by a non-covalent functionalization method based on the adsorption of a pyrimidine-desferrioxamine-B conjugate compound (H{sub 4}L) on two activated carbons, ACs (labelled Merck and F). The adsorption of H{sub 4}L on the ACs is pH-dependent and highly irreversible. This is due to strong π-π interactions between the arene centers of the ACs and the pyrimidine moiety of H{sub 4}L. The textural characterization of the AC/H{sub 4}L hybrids shows large decreases of their surface areas. Thus the values of Merck and F are 1031 and 1426 m{sup 2}/g respectively, while these of Merck/H{sub 4}L and F/H{sub 4}L hybrids are 200 and 322 m{sup 2}/g. An important decrease in the micropore volumes is also found, due to the blockage of narrow porosity produced by the adsorption of H{sub 4}L molecules. The ACs/H{sub 4}L hybrids show larger adsorption capacities for Cu(II) (0.105(4) and 0.13(2) mmol/g, at pH 2.0, and 0.20(3) and 0.242(9) mmol/g, at pH 5.5, for Merck/H{sub 4}L and F/H{sub 4}L, respectively) than those of the ACs (0.024(6) and 0.096(9) mmol/g, at pH 2.0, and 0.10(2) and 0.177(8) mmol/g, at pH 5.5, for Merck and F respectively), which is explained on the basis of the complexing ability of the trihydroxamic acid functions. The desorption of Cu(II) from the ACs/H{sub 4}L/Cu(II) materials in acid solution allows the regeneration of most active sites (78.5% in the case of Merck/H{sub 4}L/Cu(II) and 83

  7. Red Orange: Experimental Models and Epidemiological Evidence of Its Benefits on Human Health

    Directory of Open Access Journals (Sweden)

    Giuseppe Grosso

    2013-01-01

    Full Text Available In recent years, there has been increasing public interest in plant antioxidants, thanks to the potential anticarcinogenic and cardioprotective actions mediated by their biochemical properties. The red (or blood orange (Citrus sinensis (L. Osbeck is a pigmented sweet orange variety typical of eastern Sicily (southern Italy, California, and Spain. In this paper, we discuss the main health-related properties of the red orange that include anticancer, anti-inflammatory, and cardiovascular protection activities. Moreover, the effects on health of its main constituents (namely, flavonoids, carotenoids, ascorbic acid, hydroxycinnamic acids, and anthocyanins are described. The red orange juice demonstrates an important antioxidant activity by modulating many antioxidant enzyme systems that efficiently counteract the oxidative damage which may play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes, and cancer. The beneficial effects of this fruit may be mediated by the synergic effects of its compounds. Thus, the supply of natural antioxidant compounds through a balanced diet rich in red oranges might provide protection against oxidative damage under differing conditions and could be more effective than, the supplementation of an individual antioxidant.

  8. Red orange: experimental models and epidemiological evidence of its benefits on human health.

    Science.gov (United States)

    Grosso, Giuseppe; Galvano, Fabio; Mistretta, Antonio; Marventano, Stefano; Nolfo, Francesca; Calabrese, Giorgio; Buscemi, Silvio; Drago, Filippo; Veronesi, Umberto; Scuderi, Alessandro

    2013-01-01

    In recent years, there has been increasing public interest in plant antioxidants, thanks to the potential anticarcinogenic and cardioprotective actions mediated by their biochemical properties. The red (or blood) orange (Citrus sinensis (L.) Osbeck) is a pigmented sweet orange variety typical of eastern Sicily (southern Italy), California, and Spain. In this paper, we discuss the main health-related properties of the red orange that include anticancer, anti-inflammatory, and cardiovascular protection activities. Moreover, the effects on health of its main constituents (namely, flavonoids, carotenoids, ascorbic acid, hydroxycinnamic acids, and anthocyanins) are described. The red orange juice demonstrates an important antioxidant activity by modulating many antioxidant enzyme systems that efficiently counteract the oxidative damage which may play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes, and cancer. The beneficial effects of this fruit may be mediated by the synergic effects of its compounds. Thus, the supply of natural antioxidant compounds through a balanced diet rich in red oranges might provide protection against oxidative damage under differing conditions and could be more effective than, the supplementation of an individual antioxidant.

  9. Chitosan and fungicides on postharvest control of Guignardia citricarpa and on quality of 'Pêra Rio' oranges

    Directory of Open Access Journals (Sweden)

    Maria Cristina Canale Rappussi

    2011-09-01

    Full Text Available Citrus fruits are affected by the black spot disease caused by the fungus Guignardia citricarpa. Chitosan can be used as covering for fruits and may delay the ripening process and inhibit the growth of some fungi. Thus, the control of citrus black spot using chitosan and the fungicides thiabendazole and imazalil was assessed in addition to the physicochemical quality of 'Pêra Rio' oranges. The oranges were immersed into chitosan, thiabendazole or imazalil, and in chitosan mixed with both fungicides. The fruits were then stored at 25 °C, 80% RH, for 7 days and, after this storage period, subjected to physicochemical analyses. Chitosan in association with the fungicides reduced black spot in 'Pêra Rio' oranges and delayed the change in the orange skin colour from green to yellow during the postharvest storage. Total soluble solids, titratable acidity, pH, ascorbic acid content and ratio were not influenced by the treatments. Thus, chitosan applied with the fungicides thiabendazole and imazalil showed potential to control the development of black spot lesions on 'Pêra Rio' oranges during the postharvest period.

  10. Mechanistic insight into chromium(VI) reduction by oxalic acid in the presence of manganese(II)

    Energy Technology Data Exchange (ETDEWEB)

    Wrobel, Katarzyna; Corrales Escobosa, Alma Rosa; Gonzalez Ibarra, Alan Alexander; Mendez Garcia, Manuel; Yanez Barrientos, Eunice; Wrobel, Kazimierz, E-mail: kazimier@ugto.mx

    2015-12-30

    Over the past few decades, reduction of hexavalent chromium (Cr(VI)) has been studied in many physicochemical contexts. In this research, we reveal the mechanism underlying the favorable effect of Mn(II) observed during Cr(VI) reduction by oxalic acid using liquid chromatography with spectrophotometric diode array detector (HPLC–DAD), nitrogen microwave plasma atomic emission spectrometry (HPLC–MP-AES), and high resolution mass spectrometry (ESI–QTOFMS). Both reaction mixtures contained potassium dichromate (0.67 mM Cr(VI)) and oxalic acid (13.3 mM), pH 3, one reaction mixture contained manganese sulfate (0.33 mM Mn(II)). In the absence of Mn(II) only trace amounts of reaction intermediates were generated, most likely in the following pathways: (1) Cr(VI) → Cr(IV) and (2) Cr(VI) + Cr(IV) → 2Cr(V). In the presence of Mn(II), the active reducing species appeared to be Mn(II) bis-oxalato complex (J); the proposed reaction mechanism involves a one-electron transfer from J to any chromium compound containing Cr=O bond, which is reduced to Cr−OH, and the generation of Mn(III) bis-oxalato complex (K). Conversion of K to J was observed, confirming the catalytic role of Mn(II). Since no additional acidification was required, the results obtained in this study may be helpful in designing a new, environmentally friendly strategy for the remediation of environments contaminated with Cr(VI).

  11. Electrochemicla Behavior of Ascorbic Acid on Hexaaza Macrocyclic Copper(II) Complex Modified Au Electrode and Its Analytical Application

    Institute of Scientific and Technical Information of China (English)

    WU,Hai-Xia; DONG,Shu-Qing; KANG,Jing-Wan; LU,Xiao-Quan

    2008-01-01

    A novel hexaaza macrocyclic copper(II) complex modified Au electrode was developed and used for the measurement of ascorbic acid. Its electrochemical behavior was investigated by cyclic voltammetry and scanning electrochemical microscopy. This modified electrode exhibited electrocatalytic response to the oxidation of ascorbic acid. Compared with a bare gold electrode, the modified electrode exhibited a 250 mV shift of the oxidation potential of ascorbic acid in the cathodic direction and a marked enhancement of the current response. The response current revealed a good linear relationship with the concentration of ascorbic acid in the range of 5.0×10-7 to 4.0× 10-5 mol/L and the detection limit of 4.8× 10-8 mol/L (S/N=3) in the pH 4.0 Tris-HCl buffer of ascorbic acid in fruits without any other pretreatment. The concentrations of ascorbic acid measured by this method were in good agreement with the literature values. It is very promising for the modified electrode to be used as an electrochemical sensor for the detection of ascorbic acid.

  12. Treatment of Azo-dye Orange II with Nozzle-cylinder Electrode by Negative High-voltage Pulse Discharge System Combined with Ti02 Photocatalysis%喷嘴-筒式放电极负高压脉冲放电协同二氧化钛光催化对偶氮类染料酸性橙Ⅱ的处理

    Institute of Scientific and Technical Information of China (English)

    王少启; 孙明; 鲁晓辉; 郝夏桐

    2012-01-01

    The pulse discharge system produce discharge plasma and the high-energy electron, ultraviolet light, ozone etc, can be comprehensively dealt with water or atmospheric pollutants. In this paper, pulse discharge system combined with TiO2 photocatalysis, by designing nozzle-electrode of nozzle-cylinder reactor with coating of TiO2. With using ultraviolet of pulse discharge process to achieve catalytic of TiO2, for increaseing the active radicals quantity of primarily hydroxyl, The paper studied the azo-dye Orange Ⅱ to compare with coating of TiO2 electrode on degradation rate of pollutants. The main research is about degradation rate of acid orange Ⅱ in respectively with before and after coating on pulse peak voltage, pulse repetition frequency, discharge electrode diameter, initial concentration of solution and other factors.%脉冲放电过程在产生放电等离子体的同时,产生高能电子、紫外光.O3等多因素,可综合作用于水中或大气中的污染物。本文把脉冲放电等离子体和TiO2光催化相结合,对我们设计的喷嘴一筒式反应器中的喷嘴放电极进行二氧化钛镀膜,利用脉冲放电过程中的紫外光实现对二氧化钛的催化.增加放电过程以羟基为主的活性自由基的数量。以偶氮类染料酸性橙Ⅱ为研究对象,对比了放电极二氧化钛镀膜对放电等离子体技术对污染物降解效率的影响。研究了镀膜前后分别脉冲峰值电压,溶液初始浓度、溶液pH值、电导率等因素对偶氮类染料酸性橙Ⅱ液降解率的影响。

  13. Photophysical Studies of Ru(II)tris(2,2`-bipyridine) Confined within a Zn(II)-Trimesic Acid Polyhedral Metal-Organic Framework

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Randy W; Wojtas, Lukasz [USF

    2012-10-25

    The ability to confine photoactive catalysts within metal-organic framework (MOF) materials affords the opportunity to expand the functional diversity of these materials into solar based applications. Here, the confinement of Ru(II)tris(2,2'-bipyridine) (RuBpy) by a MOF material derived from Zn(II) ions and trimesic acid (hereafter, USF2) is examined. Although the encapsulated RuBpy could not be crystallographically resolved within the MOF framework, the photophysical properties of the complex are characteristic of confinement including extended triplet metal-to-ligand (3MLCT) lifetime (τethanol = 614 ns and {τUSF2 = 1.2 μs at 25 °C) and a slight hypsochromic shift in the steady-state emission spectrum relative to RuBpy in ethanol. The extended lifetime is attributed to a deactivation of a nonradiative 3dd that is antibonding with respect to the Ru(II)-bipyridine due to a confined molecular environment. These results represent one of the first examples of RuBpy encapsulation and photophysical characterization within a polyhedral MOF material.

  14. Equilibrium CH acidity of Ni(II) complexes of Schiff's bases of amino acids with S-2-N-(N'-benzylprolyl)amino-benzaldehyde and S-2-N-(N'-benzylprolyl)aminobenzophenone

    Energy Technology Data Exchange (ETDEWEB)

    Terekhova, M.I.; Belokon' , Yu.N.; Maleev, V.I.; Chernoglazova, N.I.; Kochetkov, K.A.; Belikov, V.M.; Petrov, E.S.

    1986-10-20

    By metal exchange in DMSO (K/sup +/ cation) pK values have been measured for a series of acids which are Ni(II) complexes of Schiff's bases of the amino acids Gly, S-Ala, and S-Val, with S-2-N-(N'-benzylprolyl)aminobenzaldehyde and S-2-N-(N'-benzylprolyl)aminobenzophenone. The amino acid fragment in the studied Ni(II) complexes possesses high acidity close to fluorene but five orders of magnitude greater than for acetophenone and approaching nitroalkanes in acidity.

  15. Crystal structures of two nickel compounds comprising neutral Ni(II) hydrazone complexes and di-carb-oxy-lic acids.

    Science.gov (United States)

    Nakanishi, Takumi; Sato, Osamu

    2017-02-01

    Two isostructural Ni(II) compounds, bis-{N-[1-(pyridin-2-yl-κN)eth-ylidene]pyridine-4-carbohydrazonato-κ(2)N',O}nickel(II)-2,5-di-chloro-terephthalic acid (1/1), [Ni(C13H11N4O)2](C8H4Cl2O4), and bis-{N-[1-(pyridin-2-yl-κN)eth-ylidene]pyridine-4-carbohydrazonato-κ(2)N',O}nickel(II)-2,5-di-bromo-terephthalic acid (1/1), [Ni(C13H11N4O)2](C8H4Br2O4), were synthesized and their crystal structures determined. The pair of N,N',O-tridentate N-[1-(pyridin-2-yl-κN)eth-yl]pyridine-4-carbohydrazonate L ligands result in a cis-NiO2N4 octa-hedral coordination sphere for the metal ions. The asymmetric units consist of two half-mol-ecules of the di-carb-oxy-lic acids, which are completed by crystallographic inversion symmetry. In the respective crystals, the 2,5-di-chloro-terephthalic acid (H2Cl2TPA, 1-Cl) mol-ecules form zigzag hydrogen-bonded chains with the [Ni(L)2] mol-ecules, with the hydrogen-bond distances in 1-Br slightly longer than those in 1-Cl. The packing is consolidated by aromatic π-π stacking between the di-carb-oxy-lic acid mol-ecules and terminal pyridine rings in [Ni(L)2] and short halogen-halogen inter-actions are also observed. The qualitative prediction of the H-atom position from the C-N-C angles of the terminal pyridine rings in L and the C-O distances in the carboxyl groups show that 1-Cl and 1-Br are co-crystals rather than salts.

  16. Degradation of orange dyes and carbamazepine by soybean peroxidase immobilized on silica monoliths and titanium dioxide.

    Science.gov (United States)

    Calza, Paola; Zacchigna, Dario; Laurenti, Enzo

    2016-12-01

    In this paper, the removal of three common dyes (orange I, orange II, and methylorange) and of the anticonvulsant drug carbamazepine from aqueous solutions by means of enzymatic and photocatalytic treatment was studied. Soybean peroxidase (SBP) was used as biocatalyst, both free in solution and immobilized on silica monoliths, and titanium dioxide as photocatalyst. The combination of the two catalysts led to a faster (about two to four times) removal of all the orange dyes compared to the single systems. All the dyes were completely removed within 2 h, also in the presence of immobilized SBP. As for carbamazepine, photocatalytic treatment prevails on the enzymatic degradation, but the synergistic effect of two catalysts led to a more efficient degradation; carbamazepine's complete disappearance was achieved within 60 min with combined system, while up to 2 h is required with TiO2 only.

  17. Physical properties of inulin and inulin-orange juice: physical characterization and technological application.

    Science.gov (United States)

    Saavedra-Leos, M Z; Leyva-Porras, C; Martínez-Guerra, E; Pérez-García, S A; Aguilar-Martínez, J A; Álvarez-Salas, C

    2014-05-25

    In this work two systems based on a carbohydrate polymer were studied: inulin as model system and inulin-orange juice as complex system. Both system were stored at different water activity conditions and subsequently characterized. Water adsorption isotherms type II were fitted by the GAB model and the water monolayer content was determined for each system. From thermal analyzes it was found that at low water activities (aw) systems were fully amorphous. As aw increased, crystallinity was developed. This behavior was corroborated by X-ray diffraction. In the inulin-orange juice system, crystallization appears at lower water activity caused by the intensification of the chemical interaction of the low molecular weight species contained in orange juice. Glass transition temperature (Tg), determined by modulated differential scanning calorimeter, decreased with aw. As water is adsorbed, the physical appearance of samples changed which could be observed by optical microscopy and effectively related with the microstructure found by scanning electron microscopy.

  18. ANALYSIS OF PERFLUORINATED CARBOXYLIC ACIDS IN SOILS II: OPTIMIZATION OF CHROMATOGRAPHY AND EXTRACTION

    Science.gov (United States)

    With the objective of detecting and quantitating low concentrations of perfluorinated carboxylic acids (PFCAs), including perfluorinated octanoic acid (PFOA), in soils, we compared the analytical suitability of liquid chromatography columns containing three different stationary p...

  19. ANALYSIS OF PERFLUORINATED CARBOXYLIC ACIDS IN SOILS II: OPTIMIZATION OF CHROMATOGRAPHY AND EXTRACTION

    Science.gov (United States)

    With the objective of detecting and quantitating low concentrations of perfluorinated carboxylic acids (PFCAs), including perfluorinated octanoic acid (PFOA), in soils, we compared the analytical suitability of liquid chromatography columns containing three different stationary p...

  20. Enhanced performance of Zn(II)-doped lead-acid batteries with electrochemical active carbon in negative mass

    Science.gov (United States)

    Xiang, Jiayuan; Hu, Chen; Chen, Liying; Zhang, Dong; Ding, Ping; Chen, Dong; Liu, Hao; Chen, Jian; Wu, Xianzhang; Lai, Xiaokang

    2016-10-01

    The effect and mechanism of Zn(II) on improving the performances of lead-acid cell with electrochemical active carbon (EAC) in negative mass is investigated. The hydrogen evolution of the cell is significantly reduced due to the deposition of Zn on carbon surface and the increased porosity of negative mass. Zn(II) additives can also improve the low-temperature and high-rate capacities of the cell with EAC in negative mass, which ascribes to the formation of Zn on lead and carbon surface that constructs a conductive bridge among the active mass. Under the co-contribution of EAC and Zn(II), the partial-state-of-charge cycle life is greatly prolonged. EAC optimizes the NAM structure and porosity to enhance the charge acceptance and retard the lead sulfate accumulation. Zn(II) additive reduces the hydrogen evolution during charge process and improves the electric conductivity of the negative electrode. The cell with 0.6 wt% EAC and 0.006 wt% ZnO in negative mass exhibits 90% reversible capacity of the initial capacity after 2100 cycles. In contrast, the cell with 0.6 wt% EAC exhibits 84% reversible capacity after 2100 cycles and the control cell with no EAC and Zn(II) exhibits less than 80% reversible capacity after 1350 cycles.

  1. Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

    Energy Technology Data Exchange (ETDEWEB)

    Damayanti, Astrilia, E-mail: liasholehasd@gmail.com [Department of Chemical Engineering, Faculty of Engineering, Semarang State University, E1 Building, 2nd floor, Kampus Sekaran, Gunungpati, Semarang 50229 (Indonesia); Department of Chemical Engineering, Faculty of Engineering, Gadjah Mada University, Jl. Grafika No. 2, Kampus UGM, Yogyakarta 55281 (Indonesia); Sarto,; Syamsiah, Siti; Sediawan, Wahyudi B. [Department of Chemical Engineering, Faculty of Engineering, Gadjah Mada University, Jl. Grafika No. 2, Kampus UGM, Yogyakarta 55281 (Indonesia)

    2015-12-29

    Enriched–immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid.

  2. Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

    Science.gov (United States)

    Damayanti, Astrilia; Sarto, Syamsiah, Siti; Sediawan, Wahyudi B.

    2015-12-01

    Enriched-immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid.

  3. Actions of Xanthurenic acid, a putative endogenous Group II metabotropic glutamate receptor agonist, on sensory transmission in the thalamus.

    Science.gov (United States)

    Copeland, C S; Neale, S A; Salt, T E

    2013-03-01

    Xanthurenic acid (XA), a molecule arising from tryptophan metabolism by transamination of 3-hydroxykynurenine, has recently been identified as an endogenous Group II (mGlu2 and mGlu3) metabotropic glutamate (mGlu) receptor ligand in vitro. Impairments in Group II mGlu receptor expression and function have been implicated in the pathophysiology of schizophrenia, as have multiple steps in the kynurenine metabolism pathway. Therefore, we examined XA in vivo to further investigate its potential as a Group II mGlu receptor ligand using a preparation that has been previously demonstrated to efficiently reveal the action of other Group II mGlu receptor ligands in vivo. Extracellular single-neurone recordings were made in the rat ventrobasal thalamus (VB) in conjunction with iontophoresis of agonists, an antagonist and a positive allosteric modulator and/or intravenous (i.v.) injection of XA. We found the XA effect on sensory inhibition, when applied iontophoretically and i.v., was similar to that of other Group II mGlu receptor agonists in reducing inhibition evoked in the VB from the thalamic reticular nucleus upon physiological sensory stimulation. Furthermore, we postulate that XA may be the first potential endogenous allosteric agonist (termed 'endocoid') for the mGlu receptors. As the Group II receptors and kynurenine metabolism pathway have both been heavily implicated in the pathophysiology of schizophrenia, XA could play a pivotal role in antipsychotic research as this potential endocoid represents both a convergence within these two biological parameters and a novel class of Group II mGlu receptor ligand. This article is part of a Special Issue entitled 'Metabotropic Glutamate Receptors'.

  4. Isonicotinic acid-ligated cobalt (II phthalocyanine-modified titania as photocatalyst for benzene degradation via fluorescent lamp

    Directory of Open Access Journals (Sweden)

    Joey Andrew A. Valinton

    2016-06-01

    Full Text Available The utilization of bis(isonicotinic acidphthalocyaninatocobalt (II [CoPc(isa2] incorporated on TiO2 has been studied as a photocatalyst to degrade benzene vapor under fluorescent lamp (indoor light conditions. The photocatalytic activity of [CoPc(isa2]-TiO2 compared to TiO2 showed an increase in the extent of degradation. The axial isonicotinic acid ligand attached to CoPc improved the degradation rate of benzene as compared with unligated CoPc-TiO2 which may be attributed to the enhancement of electronic structure in the complex due to the additional isonicotinic acid ligand and its possible attachment to the TiO2 surface through the carboxylic acid moiety. Therefore, covalently-linked CoPc(isa2 to TiO2 can enhance the extent of photodegradation of benzene and other common volatile organic compounds under indoor lighting conditions.

  5. Kinetics of the oxidative hydroxylation of sodium hypophosphite in the presence of copper (II chloride modified by humic (fulvo- acid

    Directory of Open Access Journals (Sweden)

    Zhaksyntay Kairbekov

    2012-12-01

    Full Text Available It was established that in soft conditions (50-70oC, PO2 = 1 atm sodium hypophosphite effectively is oxidized by oxygen in water solutions of copper(II chloride  to give mainly a phosphorous acid. Humic (fulvo- acid was extracted from brown coal of domestic deposit Kiyakty. For determination of optimum parameters of fulvo-acid extraction the laboratory experiments were carried out using the method of experiment planning. The kinetics, the intermediate and final products, optimal conditions of new catalytic reaction of NaH2PO2 oxidation by oxygen in water solution were defined by kinetics, volumometry, redox-potentiometry and a titration.

  6. Structure of the human beta-ketoacyl [ACP] synthase from the mitochondrial type II fatty acid synthase

    DEFF Research Database (Denmark)

    Christensen, Caspar Elo; Kragelund, Birthe Brandt; Von Wettstein-Knowles, Penny

    2007-01-01

    Two distinct ways of organizing fatty acid biosynthesis exist: the multifunctional type I fatty acid synthase (FAS) of mammals, fungi, and lower eukaryotes with activities residing on one or two polypeptides; and the dissociated type II FAS of prokaryotes, plastids, and mitochondria with individual...... activities encoded by discrete genes. The beta-ketoacyl [ACP] synthase (KAS) moiety of the mitochondrial FAS (mtKAS) is targeted by the antibiotic cerulenin and possibly by the other antibiotics inhibiting prokaryotic KASes: thiolactomycin, platensimycin, and the alpha-methylene butyrolactone, C75. The high...... degree of structural similarity between mitochondrial and prokaryotic KASes complicates development of novel antibiotics targeting prokaryotic KAS without affecting KAS domains of cytoplasmic FAS. KASes catalyze the C(2) fatty acid elongation reaction using either a Cys-His-His or Cys-His-Asn catalytic...

  7. Disposable biosensor based on cathodic electrochemiluminescence of tris(2,2-bipyridine)ruthenium(II) for uric acid determination

    Energy Technology Data Exchange (ETDEWEB)

    Ballesta-Claver, J.; Rodríguez-Gómez, R. [ECsens, Department of Analytical Chemistry, Campus Fuentenueva, Faculty of Sciences, University of Granada, E-18071 Granada (Spain); Capitán-Vallvey, L.F., E-mail: lcapitan@ugr.es [ECsens, Department of Analytical Chemistry, Campus Fuentenueva, Faculty of Sciences, University of Granada, E-18071 Granada (Spain)

    2013-04-03

    Highlights: ► Cathodic ECL offers conventional and non-aggressive analysis conditions. ► The ECL hydrogen peroxide/ruthenium complex system for uric acid determination is novel. ► The ruthenium complex is electrochemically immobilized on graphite screen-printed electrodes. ► The quantification of the uric acid is based on a Stern–Volmer type equation. ► The use of the cathodic ECL working methodology reduces interferences during analysis. -- Abstract: A new method for uric acid (UA) determination based on the quenching of the cathodic ECL of the tris(2,2-bipyridine)ruthenium(II)–uricase system is described. The biosensor is based on a double-layer design containing first tris(2,2-bipyridine)ruthenium(II) (Ru(bpy){sub 3}{sup 2+}) electrochemically immobilized on graphite screen-printed cells and uricase in chitosan as a second layer. The uric acid biosensing is based on the ECL quenching produced by uric acid over the cathodic ECL caused by immobilized Ru(bpy){sub 3}{sup 2+} in the presence of uricase. The use of a −1.1 V pulse for 1 s with a dwelling time of 10 s makes it possible to estimate the initial enzymatic rate, which is used as the analytical signal. The Stern–Volmer type calibration function shows a dynamic range from 1.0 × 10{sup −5} to 1.0 × 10{sup −3} M with a limit of detection of 3.1 × 10{sup −6} M and an accuracy of 13.6% (1.0 × 10{sup −4} M, n = 5) as relative standard deviation. Satisfactory results were obtained for urine samples, creating an affordable alternative for uric acid determination.

  8. Chemotaxonomic Evaluation of Species of Turkish Salvia: Fatty Acid Composition of Seed Oils. II

    Directory of Open Access Journals (Sweden)

    Turgut Kılıç

    2007-05-01

    Full Text Available Fatty acids composition of seed oil of Salvia viridis, S. hydrangea, S. blepharochleana, S. chianantha, S. staminea, S. hypergeia,, S. cilicica, S. caespitosa, S. sclarea, S. cadmica, S. microstegia, S. pachystachys and S. verticillata were analyzed by GC/MS. The main compound were found to be as linoleic acid (18:2; 12.8 % to 52.2 %, linolenic acid (18:3; 3.2 % to 47.7 %, oleic acid (18:1; 11.3 % to 25.6 %, palmitic acid (16:0; 0.7 % to 16.8 % and stearic acid (18:0; 1.8 % to 4.8 %. A phylogenetic tree of species of Salvia were reported and compared to 18:3/18:2 ratio of the seed oils. Fatty acid composition of Salvia seed oils could be used as a chemotaxonomical marker.

  9. Solid phase extraction of zinc(II) using a PVC-based polymer inclusion membrane with di(2-ethylhexyl)phosphoric acid (D2EHPA) as the carrier.

    Science.gov (United States)

    Kolev, Spas D; Baba, Yoshinari; Cattrall, Robert W; Tasaki, Tsutomu; Pereira, Natalie; Perera, Jilska M; Stevens, Geoffrey W

    2009-05-15

    A polymer inclusion membrane (PIM) is reported consisting of 45% (m/m) di(2-ethylhexyl)phosphoric acid (D2EHPA) immobilized in poly(vinyl chloride) (PVC) for use as a solid phase absorbent for selectively extracting Zn(II) from aqueous solutions in the presence of Cd(II), Co(II), Cu(II), Ni(II) and Fe(II). Interference from Fe(III) in the sample is eliminated by precipitation with orthophosphate prior to the extraction of Zn(II). Studies using a dual compartment transport cell have shown that the Zn(II) flux (2.58 x 10(-6)mol m(-2)s(-1)) is comparable to that observed for supported liquid membranes. The stoichiometry of the extracted complex is shown to be ZnR(2).HR, where R is the D2EHPA anion.

  10. Amino acid metabolism of Astacus leptodactylus (Esch.)—II. Biosynthesis of the non-essential amino acids

    NARCIS (Netherlands)

    Marrewijk, Willibrordus J.A.; Zandee, Daniel I.

    1975-01-01

    1. 1. Incubation of Astacus leptodactylus with U-14C-glucose or 1-14C-acetate induced labelling of α- and β-alanine, aspartic and glutamic acids, glutamine, glycine, proline and serine. No radioactivity was incorporated into arginine, asparagine, histidine, isoleucine, leucine, lysine, ornithine, ph

  11. Amino acid metabolism of Astacus leptodactylus (Esch.)—II. Biosynthesis of the non-essential amino acids

    NARCIS (Netherlands)

    Marrewijk, Willibrordus J.A.; Zandee, Daniel I.

    1975-01-01

    1. 1. Incubation of Astacus leptodactylus with U-14C-glucose or 1-14C-acetate induced labelling of α- and β-alanine, aspartic and glutamic acids, glutamine, glycine, proline and serine. No radioactivity was incorporated into arginine, asparagine, histidine, isoleucine, leucine, lysine, ornithine, ph

  12. Human Retroviruses and AIDS. A compilation and analysis of nucleic acid and amino acid sequences: I--II; III--V

    Energy Technology Data Exchange (ETDEWEB)

    Myers, G.; Korber, B. [eds.] [Los Alamos National Lab., NM (United States); Wain-Hobson, S. [ed.] [Laboratory of Molecular Retrovirology, Pasteur Inst.; Smith, R.F. [ed.] [Baylor Coll. of Medicine, Houston, TX (United States). Dept. of Pharmacology; Pavlakis, G.N. [ed.] [National Cancer Inst., Frederick, MD (United States). Cancer Research Facility

    1993-12-31

    This compendium and the accompanying floppy diskettes are the result of an effort to compile and rapidly publish all relevant molecular data concerning the human immunodeficiency viruses (HIV) and related retroviruses. The scope of the compendium and database is best summarized by the five parts that it comprises: (I) HIV and SIV Nucleotide Sequences; (II) Amino Acid Sequences; (III) Analyses; (IV) Related Sequences; and (V) Database Communications. Information within all the parts is updated at least twice in each year, which accounts for the modes of binding and pagination in the compendium.

  13. Adsorption of β-cyclodextrin functionalized graphene nanosheets for removal of Acid Scarlet G and Orange Ⅱ in wastewater%β-环糊精功能化石墨烯对印染废水中酸性大红G和橙黄Ⅱ的吸附

    Institute of Scientific and Technical Information of China (English)

    任宏瑛; 童馨苇; 韩玉洁; 付鹏飞; 郭玉晶

    2016-01-01

    In textile industry,azo dyes and degradation products can be released into environment via wastewater during the dying process.They are toxic,mutagenic or carcinogenic,which pose a threat to human health.This paper describes the synthesis of β-cyclodextrin functionalized graphene nanosheets (β-CD-GNs) and investigation on the removal of dye pollutants.By coupling the distinctive properties of graphene and β-cyclodextrin,β-CD-GNs exhibited excellent adsorption properties for Acid Scarlet G (ASG) and Orange Ⅱ.The adsorption equilibrium time was less than 3 rmin and the adsorption rate was more than 90%.Moreover,β-CD-GNs show high adsorption ability for both ASG and Orange Ⅱ.The adsorption capacities for ASG and Orange Ⅱ were 622.2 and 534.7 mg·g-1,respectively.The effect of pH and temperature were also investigated.The results indicated that the optimal amount ofβ-CD-GNs was 25 mg·L-1 and the optimal pH was 6.0.The adsorption behaviors of ASG and Orange Ⅱ on β-CD-GNs conformed to the Langrnuir isotherms model.%本文合成了β-环糊精功能化的石墨烯纳米材料(3-CD-GNs),考察了其作为一种新型高效吸附剂对水中酸性大红G(ASG)和橙黄Ⅱ(OrangeⅡ)的吸附性能.该材料结合了石墨烯和β-环糊精的特性,表现出对所述两种染料良好的吸附性能,吸附平衡时间小于3 min,吸附率达90%以上,β-CD-GNs对ASG和橙黄Ⅱ的最大吸附量为622.2 mg·g-1和534.7 mg·g-1.另外,考察了β-CD-GNs用量、溶液pH、反应温度对吸附效果的影响.结果表明,当溶液pH值为6.0,β-CD-GNs浓度达到25 mg·L-1时,吸附率最大,而且吸附率随反应温度升高而降低.通过对吸附数据进行线性拟合发现,3-CD-GNs对ASG和橙黄Ⅱ的吸附等温线符合Langmuir吸附等温式.该材料在印染废水的处理领域有潜在的应用价值.

  14. Effects of low molecular weight organic acids on the immobilization of aqueous Pb(II) using phosphate rock and different crystallized hydroxyapatite.

    Science.gov (United States)

    Wei, Wei; Cui, Jing; Wei, Zhenggui

    2014-06-01

    Understanding the effects of low molecular weight organic acids (LMWOAs) on the transformation of Pb(II) to geochemically stable pyromorphite (PY) by apatite materials (AMs), has considerable benefits for risk assessment and remediation strategies for contaminated water and soil. In this study, we systematically investigated the immobilization of Pb(II) from aqueous solution by natural phosphate rock (PR) and different crystallized hydroxyapatite (HAp) in the absence and presence of LMWOAs (oxalic, malic and citric acids). The results indicated that the effectiveness of PR and HAp in immobilizing Pb(II) followed in descending order by HAp2 (the poorly crystallized HAp), HAp1 (the well crystallized HAp) and PR, regardlessof the presence of LMWOAs. The presence of malic and citric acids significantly decreased the immobilizationefficiency of Pb(II) by HAp1 and PR, clarifying the lower adsorption affinities of Pb(II)-organic acid complexes on HAp1 and PR rather than Pb(II) ion. On thecontrary, oxalic acid could markedly enhance the removal of Pb(II) from aqueous solution by HAp1 and PR through the formation of lead oxalate, which was confirmed by FT-IR and XRDanalysis. Results also showed that LMWOAs had little promoting or inhibiting effect on the immobilization of Pb(II) by HAp2. This study suggested that the ubiquity of LMWOAs in natural environments could retard the transformation efficiency of Pb(II) to PY by AMs, especiallyin thepresenceof oxalic acid, and the poorly crystallized HAp2 had great potential to remediate Pb(II)-contaminated water and soil due to its insusceptibility to LMWOAs.

  15. Removal of aqueous Hg(II) and Cr(VI) using phytic acid doped polyaniline/cellulose acetate composite membrane.

    Science.gov (United States)

    Li, Renjie; Liu, Lifen; Yang, Fenglin

    2014-09-15

    Conductive composite membrane-phytic acid (PA) doped polyaniline (PANI)/cellulose acetate (CA) (PANI-PA/CA) was prepared in a simple and environmental-friendly method, in which aniline was blended with CA/PA solution and polymerized before the phase conversion. The resultant composite membranes were characterized by SEM, EDX, FTIR-ATR, BET and electrical resistance measurements. When used as adsorbent for Hg(II) and Cr(VI) ions, the prepared composite membrane exhibits excellent adsorption capability. The adsorption of Hg(II) and Cr(VI) follows a pseudo-second-order kinetic model and best fits the Langmuir isotherm model, with the maximum adsorption capacity reaching 280.11 and 94.34 mg g(-1), respectively. The heavy metal loaded composite membrane can be regenerated and reused after treatment with acid or alkali solution, making it a promising and practical adsorbent for Hg(II) and Cr(VI) removal. Tests with river water were also carried out, indicating good performance and application.

  16. Copper(II) complexation by humic and fulvic acids from pig slurry and amended and non-amended soils.

    Science.gov (United States)

    Plaza, C; Senesi, N; García-Gil, J C; Polo, A

    2005-11-01

    The effect of the consecutive annual additions of pig slurry at rates of 0 (control), 90 and 150 m3 ha(-1) y(-1) over a 4-year period on the binding affinity for Cu(II) of soil humic acids (HAs) and fulvic acids (FAs) was investigated in a field plot experiment under semiarid conditions. A ligand potentiometric titration method and a single site model were used for determining the Cu(II) complexing capacities and the stability constants of Cu(II) complexes of HAs and FAs isolated from pig slurry and control and amended soils. The HAs complexing capacities and stability constants were larger than those of the corresponding FA fractions. With respect to the control soil HA, pig-slurry HA was characterized by a much smaller binding capacity and stability constant. Amendment with pig slurry decreased the binding affinity of soil HAs. Similar to the corresponding HAs, the binding affinity of pig-slurry FA was much smaller while that of amended-soil FAs were slightly smaller when compared to the control soil FA. The latter effect was, however, more evident with increasing the amount of pig slurry applied to soil per year and the number of years of pig slurry application.

  17. Complexation of Cu(II) by original tartaric acid-based ligands in nonionic micellar media: thermodynamic study and applications.

    Science.gov (United States)

    Dupont-Leclercq, Laurence; Giroux, Sébastien; Parant, Stéphane; Khoudour, Leïla; Henry, Bernard; Rubini, Patrice

    2009-04-09

    The complexation of Cu(II) with original alkylamidotartaric acids (C(x)T) is investigated in homogeneous aqueous medium and in the presence of nonionic micelles of Brij 58 (C16EO20), thanks to various analytical techniques such as NMR self-diffusion experiments, CD and UV-vis spectroscopy, ESI mass spectrometry, pHmetry and micellar-enhanced ultrafiltration (MEUF). First, a complete speciation study proves the formation of dimeric complexes in water and provides their formation constants. Second, a similar study is led in the presence of nonionic micelles. It underlines a modification of the apparent equilibrium constants in micellar medium and demonstrates that the structure of the complexes is slightly modified in the presence of micelles. This thermodynamic and structural study is applied to modelize the evolution of the extraction yields of Cu(II) by the micelles as a function of pH and to identify the complexes extracted in the micelles. The effects of the chain length of the ligand (C3T vs C8T) on the solubilization properties are put into relief and discussed. Anionic species are proved to be more incorporated in the nonionic micelles than the cationic species. The extracting system constituted of octylamidotartaric acid (CsT) solubilized in nonionic micelles of Brij 58 is demonstrated to be very efficient for the extraction of Cu(II) by MEUF, this technique being an interesting green alternative to traditional solvent extraction.

  18. Synthesis of styrenes by palladium(II)-catalyzed vinylation of arylboronic acids and aryltrifluoroborates by using vinyl acetate.

    Science.gov (United States)

    Lindh, Jonas; Sävmarker, Jonas; Nilsson, Peter; Sjöberg, Per J R; Larhed, Mats

    2009-01-01

    One Heck of a reaction: Treatment of arylboronic acids or aryltrifluoroborates with vinyl acetate by using a palladium(II) catalyst gives the corresponding styrenes (see scheme). No palladium reoxidant is needed and the vinylation is performed under non-inert conditionsReactions of aromatic and heteroaromatic boronic acids or aryltrifluoroborate salts with vinyl acetate in the presence of a palladium(II) catalyst give the corresponding styrenes in good yields. This Heck reaction proceeds with microwave heating in less than 30 min at 140 degrees C in the absence of base and tolerates a variety of substituents. No palladium reoxidant is needed and the vinylation is performed under non-inert conditions. Mass spectrometry (electrospray ionization mass spectrometry (ESIMS) and tandem mass spectrometry (MS/MS)) was used to identify cationic palladium-containing complexes in ongoing reactions. The key intermediates that have been detected, together with experiments that used deuterated vinyl acetate, support the existence of catalytically active palladium hydride species, and that it is the arylation of ethylene, not vinyl acetate, which generates the styrene product. The mechanism of the reaction is discussed in terms of the palladium(II) intermediates mentioned above.

  19. A modified ferrous oxidation-xylenol orange assay for lipoxygenase activity in rice grains.

    Science.gov (United States)

    Timabud, Tarinee; Sanitchon, Jirawat; Pongdontri, Paweena

    2013-12-01

    Ferrous oxidation-xylenol orange assay reagent was reformulated by using spectral analysis of ferric-xylenol orange complex to detect low concentrations of lipoxygenase rice grain products. Reducing the levels of ferrous sulphate and xylenol orange in the FOX reagent enabled the detection of low concentrations of hydroperoxy fatty acid derived from lipoxygenase activity in the range of 0.1-1.5 μM. Protein, substrate and time courses of the modified FOX assay were studied to determine lipoxygenase activity in rice grain. The assay was also applicable as a high throughput technique for comparisons of lipoxygenase activity from various rice varieties. This has important implications for rapid screening for low-lipoxygenase containing rice cultivars in rice breeding program and grain quality during storage. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Quantification of the amount of galacturonic acid residues in blocksequences in pectin homogalacturonan by enzymatic fingerprinting with exo- and endo-polygalacturonase II from Aspergillus niger

    DEFF Research Database (Denmark)

    Limberg, G; Körner, R; Buchholt, H C

    2000-01-01

    A method to determine the amount of galacturonic acid in blocksequence (BS) in pectin homogalacturonan (HG) is described. The method is based on a combination of endopolygalacturonase II (endo-PG II) and exopolygalacturonase (exo-PG) digestion followed by quantification of the liberated galacturo...

  1. A one-dimensional coordination polymer of 5-[(imidazol-1-yl)methyl]benzene-1,3-dicarboxylic acid with Cu(II) cations.

    Science.gov (United States)

    Patra, Ranjan; Goldberg, Israel

    2013-04-01

    5-[(Imidazol-1-yl)methyl]benzene-1,3-dicarboxylic acid (H2L) was synthesized and the dimethylformamide- and dimethylacetamide-solvated structures of its adducts with Cu(II), namely catena-poly[[copper(II)-bis[μ-3-carboxy-5-[(imidazol-1-yl)methyl]benzoato

  2. Synthesis of α-Amino Acids via Asymmetric Phase Transfer-Catalyzed Alkylation of Achiral Nickel(II) Complexes of Glycine-Derived Schiff Bases

    NARCIS (Netherlands)

    Belokon, Yuri N.; Bespalova, Natalia B.; Churkina, Tatiana D.; Císařová, Ivana; Ezernitskaya, Marina G.; Harutyunyan, Syuzanna R.; Hrdina, Radim; Kagan, Henri B.; Kočovský, Pavel; Kochetkov, Konstantin A.; Larionov, Oleg V.; Lyssenko, Konstantin A.; North, Michael; Polášek, Miroslav; Peregudov, Alexander S.; Prisyazhnyuk, Vladimir V.; Vyskočil, Štěpán

    2003-01-01

    Achiral, diamagnetic Ni(II) complexes 1 and 3 have been synthesized from Ni(II) salts and the Schiff bases, generated from glycine and PBP and PBA, respectively, in MeONa/MeOH solutions. The requisite carbonyl-derivatizing agents pyridine-2-carboxylic acid(2-benzoyl-phenyl)-amide (PBP) and pyridine-

  3. Synthesis of α-Amino Acids via Asymmetric Phase Transfer-Catalyzed Alkylation of Achiral Nickel(II) Complexes of Glycine-Derived Schiff Bases

    NARCIS (Netherlands)

    Belokon, Yuri N.; Bespalova, Natalia B.; Churkina, Tatiana D.; Císařová, Ivana; Ezernitskaya, Marina G.; Harutyunyan, Syuzanna R.; Hrdina, Radim; Kagan, Henri B.; Kočovský, Pavel; Kochetkov, Konstantin A.; Larionov, Oleg V.; Lyssenko, Konstantin A.; North, Michael; Polášek, Miroslav; Peregudov, Alexander S.; Prisyazhnyuk, Vladimir V.; Vyskočil, Štěpán

    2003-01-01

    Achiral, diamagnetic Ni(II) complexes 1 and 3 have been synthesized from Ni(II) salts and the Schiff bases, generated from glycine and PBP and PBA, respectively, in MeONa/MeOH solutions. The requisite carbonyl-derivatizing agents pyridine-2-carboxylic acid(2-benzoyl-phenyl)-amide (PBP) and

  4. Physico-chemical and biological studies of Cu(II, Co(II and Ni(II complexes of an N4 coordinating ligand derived from diacetylbisethylenediamine and benzoic acid

    Directory of Open Access Journals (Sweden)

    Singh Pal Netra

    2012-01-01

    Full Text Available Mononuclear metal complexes of the type [ML1]Cl2 (where, M = = Cu(II, Co(II or Ni(II and L1 = ligand were synthesized by the reaction of a new N4 coordinating ligand, derived from diacetylbisethylenediamine with benzoic acid, and the corresponding hydrated metal chloride salts. The metal complexes were characterized by elemental analysis, melting point determination, molar conductance and magnetic moment measurements, IR, UV-Vis, 1H- and 13C-NMR, and ESR spectroscopy. The ligand and all the metal complexes were stable in the solid state at room temperature. From the analytical and spectroscopic investigations, the stoichiometry of the complexes was found to be 1:1 (metal:ligand. Based on the electronic spectra and magnetic moment data, the metal complexes had a square planar geometry. The molar conductance values show the 1:2 electrolytic nature of the metal complexes. A cyclic voltammetric study of the Cu(II metal complex has also performed, which showed one electron quasi-reversible reduction around -0.92 to -1.10 V. In vitro biological activities of the ligand and metal complexes was checked against two bacteria Bacillus subtilis and Escherichia coli and two fungi Aspirgillus niger and A. flavus which showed the antibacterial and antifungal properties of the ligand and its metal complexes.

  5. Decolorization and detoxification of sulfonated azo dye methyl orange by Kocuria rosea MTCC 1532.

    Science.gov (United States)

    Parshetti, G K; Telke, A A; Kalyani, D C; Govindwar, S P

    2010-04-15

    Kocuria rosea (MTCC 1532) showed 100% decolorization of methyl orange (50 mg l(-1)) under static condition. The optimum pH and temperature for dye decolorization was 6.8 and 30 degrees C, respectively. The K. rosea (MTCC 1532) showed maximum decolorization of methyl orange when growth medium containing yeast extract as compared to other substrates. The culture exhibited significant ability to decolorize repeated additions of dye, with reduction in time up to 12 h at eighth dye aliquot addition. Significant induction of reductases (NADH-DCIP reductase and azoreductase) suggests its involvement in decolorization of methyl orange. The metabolites formed after decolorization of methyl orange, such as 4-amino sulfonic acid and N,N'-dimethyl p-phenyldiamine were characterized using FTIR and MS. Phytotoxicity and microbial toxicity study showed the methyl orange was toxic and metabolites obtained after its decolorization was nontoxic for experimental plants (Triticum aestivum and Phaseolus mungo) and bacteria (K. rosea, Pseudomonas aurugenosa and Azatobacter vinelandii).

  6. Cell organelles from crassulacean acid metabolism (CAM) plants : II. Compartmentation of enzymes of the crassulacean acid metabolism.

    Science.gov (United States)

    Schnarrenberger, C; Groß, D; Burkhard, C; Herbert, M

    1980-02-01

    The intracellular distribution of enzymes involved in the Crassulacean acid metabolism (CAM) has been studied in Bryophyllum calycinum Salisb. and Crassula lycopodioides Lam. After separation of cell organelles by isopycnic centrifugation, enzymes of the Crassulacean acid metabolism were found in the following cell fractions: Phosphoenolpyruvate carboxylase in the chloroplasts; NAD-dependent malate dehydrogenase in the mitochondria and in the supernatant; NADP-dependent malate dehydrogenase and phosphoenolpyruvate carboxykinase in the chloroplasts; NADP-dependent malic enzyme in the supernatant and to a minor extent in the chloroplasts; NAD-dependent malic enzyme in the supernatant and to some degree in the mitochondria; and pyruvate; orthophosphate dikinase in the chloroplasts. The activity of the NAD-dependent malate dehydrogenase was due to three isoenzymes separated by (NH4)2SO4 gradient solubilization. These isoenzymes represented 17, 78, and 5% of the activity recovered, respectively, in the order of elution. The isoenzyme eluting first was associated with the mitochondria and the second isoenzyme was of cytosolic origin, while the intracellular location of the third isoenzyme was probably the peroxisome. Based on these findings, the metabolic path of Crassulacean acid metabolism within cells of CAM plants is discussed.

  7. Synthesis, Biological, and Quantum Chemical Studies of Zn(II and Ni(II Mixed-Ligand Complexes Derived from N,N-Disubstituted Dithiocarbamate and Benzoic Acid

    Directory of Open Access Journals (Sweden)

    Anthony C. Ekennia

    2016-01-01

    Full Text Available Some mixed-ligand complexes of Zn(II and Ni(II derived from the sodium salt of N-alkyl-N-phenyl dithiocarbamate and benzoic acid have been prepared. The complexes are represented as ZnMDBz, ZnEDBz, NiMDBz, and NiEDBz (MD: N-methyl-N-phenyl dithiocarbamate, ED: N-ethyl-N-phenyl dithiocarbamate, and Bz: benzoate; and their coordination behavior was characterized on the basis of elemental analyses, IR, electronic spectra, magnetic and conductivity measurements, and quantum chemical calculations. The magnetic moment measurement and electronic spectra were in agreement with the four proposed coordinate geometries for nickel and zinc complexes and were corroborated by the theoretical quantum chemical calculations. The quantum chemically derived thermodynamics parameters revealed that the formation of N-methyl-N-phenyl dithiocarbamate complexes is more thermodynamically favourable than that of the N-ethyl-N-phenyl dithiocarbamate complexes. The bioefficacy of the mixed-ligand complexes examined against different microbes showed moderate to high activity against the test microbes. The anti-inflammatory and antioxidant studies of the metal complexes showed that the ethyl substituted dithiocarbamate complexes exhibited better anti-inflammatory and antioxidant properties than the methyl substituted dithiocarbamate complexes.

  8. Synthesis, characterization, crystal structure and antimicrobial studies of a novel Cu(II) complex based on itaconic acid and nicotinamide

    Science.gov (United States)

    Tella, Adedibu C.; Owalude, Samson O.; Ajibade, Peter A.; Simon, Nzikahyel; Olatunji, Sunday J.; Abdelbaky, Mohammed S. M.; Garcia-Granda, Santiago

    2016-12-01

    A novel complex was synthesized from Cu(II), nicotinamide and itaconic acid and is formulated as [Cu(C5H4O4)2(C6H6N2O)2(H2O)2·2(H2O)] (1). The compound was characterized by elemental analysis, FTIR spectroscopy, UV-Vis and single crystal X-ray diffraction. The complex crystallizes in the triclinic P-1 space group, with a = 7.5111(2) Å, b = 9.8529(3) Å, c = 10.5118(4) Å, α = 116.244(3)°, β = 90.291(3)°, γ = 103.335(3)°, V = 673.81(4) Å3, Z = 1.The octahedral geometry around the copper(II) ion is of the form CuN2O4 consisting of two molecules of nicotinamide acting as monodentate ligand through the nitrogen atoms, two molecules itaconate ligand and two coordinated water molecules each coordinating through the oxygen atoms. The structure of 1 showed infinite chains build up linking the molecules together via strong Osbnd H⋯O and Nsbnd H⋯O intermolecular hydrogen bonds generating a two dimensional network sheet along c axis. The antimicrobial study of the synthesized complex 1 was investigated and showed higher antibacterial activity against all the organisms comparing with Copper(II) nicotinamide 2 and Copper(II) itaconate 3.

  9. Endurance exercise after orange ingestion anaphylaxis

    Directory of Open Access Journals (Sweden)

    Manu Gupta

    2016-01-01

    Full Text Available Endurance exercise after orange ingestion cause anaphylaxis which is food-dependent exercise-induced anaphylaxis (FDEIA which is a form of exercise-induced anaphylaxis. In this article, an individual develops symptoms such as flushing, itching, urticaria, angioedema, and wheezing after eating a food allergen and proceeds to exercise. Neither the food alone nor exercise alone is sufficient to induce a reaction. This case report describes a 36-year-old asthmatic male athlete who experienced nausea, vomiting, flushing, urticaria, and facial swelling while exercising in a gymnasium after eating oranges. Neither oranges alone nor exercise alone induced the reaction. Total avoidance of suspected food allergens would be ideal. Persons with FDEIA should keep at hand an emergency kit with antihistamines, injectable rapid action corticoids, and adrenaline.

  10. Hepatocellular carcinoma in the Malaysian Orang Asli.

    Science.gov (United States)

    Sumithran, E; Prathap, K

    1976-05-01

    Necropsies were performed on 285 consecutively unclaimed Orang Asli bodies from Gombak Orang Asli Hospital during an eight-year period from May 1967 to April 1975. Of the 25 malignant neoplasms, hepatocellular carcinoma was by far the commonest (36%). The nine patients with this neoplasm had coexistant macronodular cirrhosis. There were 20 cases of cirrhosis; 45% of these had coexistant hepatocellular carcinoma. The 53,000 Orang Aslis living in West Malaysia comprise three tribes, the Negrito, Senoi, and Melayu Asli (Proto Malays). The Sinoi appear to have a high predilection for liver cancer, all our nine cases occurring in this group. These aboriginal people live in the jungles where they practice shifting cultivation and maintain their own dietary and social customs. Detailed studies of their dietary habits may provide a clue to the etiology of liver cancer in these people.

  11. Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays; Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand

    Energy Technology Data Exchange (ETDEWEB)

    Bang, P.; Eriksson, U.; Wivall, I.-L.; Hall, K. (Department of Endocrinology, Karolinska Institute, Stockholm (Sweden)); Sara, V. (Department of Pathology, Karolinska Institute, Stockholm (Sweden))

    1991-01-01

    Insulin-like growth factor binding proteins interfere in the IGF-I and -II radioimmunoassays. In an attempt to overcome this problem, we have compared the use of truncated IGF-I, with reduced IGFBP affinity, and IGF-I as radioligands for IGF-I RIA measurements in serum separated by acid gel filtration or acid ethanol extraction followed by cryo-precipitation. With truncated IGF-I as radioligand the IGF-I measurements in acid gel filtrates and acid ethanol extracts were significantly correlated in healthy subjects (N=42, r=0.91, p<0.001) and in patients with acromegaly (N=10, r=0.85, p<0.01), GH deficiency (N=10, r=0.88, p<0.001) or Type I diabetes mellitus (N=10, r=0.90, p<0.001). In contrast, the IGF-I concentrations in acid ethanol extracts determined with IGF-I as radioligand did not correlate with those in acid gel filtrates using truncated IGF-I radioligand in patients with acromegaly (r=0.61, NS) or GH deficiency (r=0.46, NS). In the latter group the mean IGF-I concentrations measured in acid ethanol extracts were erroneously elevated by 112%. Low-affinity antibodies used for IGF-II RIA determinations failed to give reliable results in acid ethanol extracts from patients with Type I diabetes mellitus or GH deficiency. In conclusion, erroneously high IGF-I concentrations owing to binding of the radioligand to IGFBPs not completely removed by acid ethanol extraction can be avoided by the use of truncated IGF-I as radioligand. (author).

  12. BIOSORPTION OF LEAD (II ON MODIFIED BARKS EXPLAINED BY THE HARD AND SOFT ACIDS AND BASES (HSAB THEORY

    Directory of Open Access Journals (Sweden)

    Cedric Astier,

    2012-01-01

    Full Text Available Chemical modification of Douglas fir bark and its subsequent utilization in adsorption of Pb(II from aqueous solutions was investigated. The polysaccharidic moiety of barks was functionalized by periodate oxidation and derivatized after reductive amination in the presence of aminated oligo-carrageenans. Pb(II adsorption isotherms of derivatized barks were then determined and compared to the capabilities of crude barks using the Langmuir adsorption model in terms of affinity (b and maximum binding capacity (qmax. Compared to crude barks, the derivatization of barks by oligo-carrageenans resulted in significant enhancements of qmax and b by up to x8 and x4, respectively. The results obtained from crude barks on chemically grafted carboxylic and sulfated barks are discussed and interpreted through the Hard and Soft Acids and Bases (HSAB theory.

  13. Aerobic C-H Acetoxylation of 8-Methylquinoline in PdII-Pyridinecarboxylic Acid Systems: Some Structure-Reactivity Relationships

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Daoyong; Zavalij, Peter Y.; Vedernikov, Andrei N.

    2013-09-09

    Catalytic oxidative C–H acetoxylation of 8-methylquinoline as a model substrate with O2 as oxidant was performed using palladium(II) carboxylate catalysts derived from four different pyridinecarboxylic acids able to form palladium(II) chelates of different size. A comparison of the rates of the substrate C–H activation and the O2 activation steps shows that the C–H activation step is rate-limiting, whereas the O2 activation occurs at a much faster rate already at 20 °C. The chelate ring size and the chelate ring strain of the catalytically active species are proposed to be the key factors affecting the rate of the C–H activation.

  14. Cu(II) complexation by "non-coordinating" N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES buffer).

    Science.gov (United States)

    Sokołowska, Magdalena; Bal, Wojciech

    2005-08-01

    The combined potentiometric and spectroscopic studies of interactions of N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) with Cu(II) demonstrated that this popular buffer, commonly labelled as "non-coordinating" forms a CuL+ complex, with the logbeta(CuL) value of 3.22. This complex undergoes alkaline hydrolysis above pH 6, resulting in Cu(OH)2 precipitation. However, the presence of HEPES at a typical concentration of 100 mM at pH 7.4 elevates the apparent binding constant, being determined for a complex of another ligand, by a factor of 80. HEPES does not form ternary complexes with aminoacids Ala, Trp, and His, but may do so with other bioligands, such as nucleotides. Therefore, HEPES can still be recommended for Cu(II) studies in place of other common buffers, such as Tris and phosphate, but appropriate corrections and precautions should be applied in quantitative experiments.

  15. Processing Technology of Fresh Orange Beverage Using Mint%薄荷鲜橙汁饮料的研制

    Institute of Scientific and Technical Information of China (English)

    阙小峰; 顾嘉豪; 谢恩耀; 司文会

    2015-01-01

    研究薄荷鲜橙汁的加工工艺,以正交试验法确定了薄荷鲜橙汁中橙汁、薄荷汁、柠檬酸和糖浆的最佳配比.结果表明,最佳的薄荷鲜橙汁工艺配比为薄荷汁25%,橙汁30%,柠檬酸0.4%,糖浆10%.所得产品色泽鲜明,呈橙黄色,无肉眼可见杂质;具橙子的清香味,薄荷的清凉和酸甜感.%The paper studies processing technology of fresh orange beverage using mint , and the optimum proportion of orange juice, mint juice, citric acid and syrup was determined by orthogonal test method. The results show that the optimal process of fresh orange juice was 25%of mint juice, 30%of orange juice, 0.4%of citric acid, and 10%of syrup. The product has a bright color of orange yellow, no visible impurities ,with orange fragrance and cool feeling of sweet-sour taste.

  16. Zeolite-Encapsulated Copper(II) Amino Acid Complexes: Synthesis, Spectroscopy, and Catalysis

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Verberckmoes, A.A.; Fu, L.; Schoonheydt, R.A.

    1995-01-01

    The spectroscopic properties and catalytic behavior of Cu(AA)n m+ complexes (AA ) amino acid (glycine, lysine, histidine, alanine, serine, proline, tyrosine, phenylalanine, glutamine, glutamic acid, cysteine, tryptophan, leucine, and arginine)) in faujasite-type zeolites have been investigated. Succ

  17. Zeolite-Encapsulated Copper(II) Amino Acid Complexes: Synthesis, Spectroscopy, and Catalysis

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Verberckmoes, A.A.; Fu, L.; Schoonheydt, R.A.

    2001-01-01

    The spectroscopic properties and catalytic behavior of Cu(AA)n m+ complexes (AA ) amino acid (glycine, lysine, histidine, alanine, serine, proline, tyrosine, phenylalanine, glutamine, glutamic acid, cysteine, tryptophan, leucine, and arginine)) in faujasite-type zeolites have been investigated. Succ

  18. Base cation deposition in Europe - Part II. Acid neutralization capacity and contribution to forest nutrition

    NARCIS (Netherlands)

    Draaijers, G.P.J.; Leeuwen, E.P. van; Jong, P.G.H. de; Erisman, J.W.

    1997-01-01

    An assessment was made of the capacity of base cations to neutralize acid deposition and of the contribution of base cation deposition to forest nutrition in Europe. In large parts of southern Europe more than 50% of the potential acid deposition was found counteracted by deposition of non-sea salt

  19. Characterization of Humic Acid in the Chemical Oxidation Technology (II) - Characteristics by Ozonation -

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D.S.; Jung, Y.R. [Kangwon National University, Chunchon (Korea)

    2000-04-01

    In this paper, ozonation of humic acid in water was characterized using UV{sub 254} absorbance, TOC, Ultra Filtration and {sup 13}C-NMR. Also, carbonyl compounds in ozonated water were analyzed by GC/MS using PFBOA method. Ozonation by-products of water containing humic acid were determined as formaldehyde, acetaldehyde, acetone, glyoxal and methylglyoxal. Results of UV{sub 254} absorbance and TOC with ozonation time at humic acid 20, 100 ppm represent that decrease rate of 80% within ozonation time is 20 min and TOC removal rate of 40-50% within ozonation time is 30 min. Results for {sup 13}C-NMR and Ultra Filtration, humic acid of high molecular weight by ozonation are oxidated and decomposed so that it was conversed low molecular weight such as aldehydes, carboxylic acid. (author). 7 refs., 3 tabs., 9 figs.

  20. Studies on chemical modification and biology of a natural product, gambogic acid (II): Synthesis and bioevaluation of gambogellic acid and its derivatives from gambogic acid as antitumor agents.

    Science.gov (United States)

    Wang, Jinxin; Ma, Junhai; You, Qidong; Zhao, Li; Wang, Fan; Li, Chong; Guo, Qinglong

    2010-09-01

    Gambogic acid (GA) has been reported to be a potent apoptosis inducer. The fact that it is amenable to chemical modification makes GA an attractive molecule for the development of anticancer agents. We firstly reported the synthesis of gambogellic acid, which was generated under acid catalysis from readily available GA by a base-catalyzed diene intramolecular annelation. Sequentially, thirteen new compounds were synthesized and their inhibitory activity on HT-29, Bel-7402, BGC-823, and A549 cell lines were evaluated in vitro by MTT assay, and (38, 40)-epoxy-33-chlorogambogellic acid (4) was identified as a BGC-823 cell apoptosis inducer through MTT cell assay, observations of morphological changes, and Annexin-V/PI double-staining assay. Compound 4 showed significant effects in inducing apoptosis and might serve as a potential lead compound for discovery of new anticancer drugs. Further structure-activity relationships (SARs) of gambogic acid derivatives were discussed.

  1. CYCLIC VOLTAMMETRY STUDIES OF COPPER (II AND TELLURIUM (IV IONS IN ACIDIC AQUEOUS SOLUTIONS FOR THIN FILM DEPOSITION

    Directory of Open Access Journals (Sweden)

    SARAVANAN NAGALINGAM

    2014-05-01

    Full Text Available Cyclic voltammetry studies of copper (II and tellurium (IV ions in acidic aqueous solutions were carried out to determine the optimum condition for copper telluride thin film deposition. The voltammetry studies include reversible scans at different solution pH. Based on the voltammogram, suitable deposition conditions was determined to be in the range of -0.35 V to -0.45 V versus Ag/AgCl at pH values between 2.0 to 2.2 under non diffusion-limited conditions.

  2. Spectrophotometric determination of copper(II) in pharmaceutical, biological and water samples by 4-(2'-benzothiazolylazo)-salicylic acid

    Science.gov (United States)

    Hashem, E. Y.; Seleim, M. M.; El-Zohry, A. M.

    2011-09-01

    A highly sensitive method is proposed to determine copper(II) ions by forming a stable complex through their interaction with 4-(2'-benzothiazolylazo)-salicylic acid (BTAS) at room temperature and pH of about 5.0. The complex gave a maximum absorption at λ = 485 nm with a molar absorptivity coefficient of 2.35·104 l/(mol·cm). The linear range for the copper determination is 0.63-5.04 mg/l. The method can be applied to determine copper ions in different biological specimens like some drugs and water samples.

  3. Complexation and coordination selectivities of the tetradentate ligand 7-[(2-hydroxy-5-sulfophenyl) azo]-8-hydroxyquinoline-5-sulfonic acid with Fe(II), Ni(II), Zn(II), Cd(II) and VO(IV)

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Hu; Kai, Fumiaki; Hirohata, Masaaki; Nakamura, Masaaki; Matsuzaki, Susumu; Komori, Kenji; Tsunematsu, Yuriko [Kumamoto Univ. (Japan)

    1993-12-31

    The new title tetradentate ligand (SPAHQS), containing both phenylazo and 8-quinolinol fragments, was prepared. Proton-dissociation processes of the ligand and complexing equilibria with Fe(II), Ni(II), Zn(II), Cd(II), and VO(IV) were analyzed spectrophotometrically. Coordination modes of SPAHQS with these metal ions have been investigated by means of polarography and Raman spectroscopy in aqueous solution. It was established that the coordination selectivity of SPAHQS for such metal ions is mainly dependent on steric factors in the chelate ring formed, not on HSAB properties. 18 refs., 6 figs., 2 tabs.

  4. Preparation and characterization of trihydroxamic acid functionalized carbon materials for the removal of Cu(II) ions from aqueous solution

    Science.gov (United States)

    Godino-Salido, M. Luz; Santiago-Medina, Antonio; López-Garzón, Rafael; Gutiérrez-Valero, María D.; Arranz-Mascarós, Paloma; López de la Torre, M. Dolores; Domingo-García, María; López-Garzón, F. Javier

    2016-11-01

    The main objective of this study is to prepare and characterize two functionalizated carbon materials with enhanced adsorptive properties for Cu(II). Thus, two novel hybrid materials have been prepared by a non-covalent functionalization method based on the adsorption of a pyrimidine-desferrioxamine-B conjugate compound (H4L) on two activated carbons, ACs (labelled Merck and F). The adsorption of H4L on the ACs is pH-dependent and highly irreversible. This is due to strong π-π interactions between the arene centers of the ACs and the pyrimidine moiety of H4L. The textural characterization of the AC/H4L hybrids shows large decreases of their surface areas. Thus the values of Merck and F are 1031 and 1426 m2/g respectively, while these of Merck/H4L and F/H4L hybrids are 200 and 322 m2/g. An important decrease in the micropore volumes is also found, due to the blockage of narrow porosity produced by the adsorption of H4L molecules. The ACs/H4L hybrids show larger adsorption capacities for Cu(II) (0.105(4) and 0.13(2) mmol/g, at pH 2.0, and 0.20(3) and 0.242(9) mmol/g, at pH 5.5, for Merck/H4L and F/H4L, respectively) than those of the ACs (0.024(6) and 0.096(9) mmol/g, at pH 2.0, and 0.10(2) and 0.177(8) mmol/g, at pH 5.5, for Merck and F respectively), which is explained on the basis of the complexing ability of the trihydroxamic acid functions. The desorption of Cu(II) from the ACs/H4L/Cu(II) materials in acid solution allows the regeneration of most active sites (78.5% in the case of Merck/H4L/Cu(II) and 83.0% in the case of F/H4L/Cu(II)).

  5. Orange proteomic fingerprinting: From fruit to commercial juices.

    Science.gov (United States)

    Lerma-García, María Jesús; D'Amato, Alfonsina; Simó-Alfonso, Ernesto F; Righetti, Pier Giorgio; Fasoli, Elisa

    2016-04-01

    Combinatorial peptide ligand library technology, coupled to mass spectrometry, has been applied to extensively map the proteome of orange pulp and peel and, via this fingerprinting, to detect its presence in commercial orange juices and drinks. The native and denaturing extraction protocols have captured 1109 orange proteins, as identified by LC-MS/MS. This proteomic map has been searched in an orange concentrate, from a Spanish juice manufacturer, as well as in commercial orange juices and soft drinks. The presence of numerous orange proteins in commercial juices has demonstrated the genuineness of these products, prepared by using orange fruits as original ingredients. However, the low number of identified proteins in sparkling beverages has suggested that they were prepared with scarce amounts of fruit extract, thus imparting lower quality to the final products. These findings not only increase the knowledge of the orange proteome but also present a reliable analytical method to assess quality and genuineness of commercial products.

  6. 21 CFR 146.150 - Canned concentrated orange juice.

    Science.gov (United States)

    2010-04-01

    ... of orange juice soluble solids in degrees Brix; for example, a 62° Brix concentrate in 1-gallon cans may be named on the label “canned concentrated orange juice, 62° Brix”. If the food does not...

  7. Synthesis and characterization of poly(maleic acid)-grafted crosslinked chitosan nanomaterial with high uptake and selectivity for Hg(II) sorption.

    Science.gov (United States)

    Ge, Huacai; Hua, Tingting

    2016-11-20

    Chitosan-poly(maleic acid) nanomaterial (PMACS) with the size of 400-900nm was synthesized by grafting poly(maleic acid) onto chitosan and then crosslinking with glutaraldehyde. The synthesis conditions were optimized. The structure and morphology of PMACS were characterized by FT-IR, XRD, SEM and TGA. PMACS was used to adsorb some heavy metal ions such as Hg(II), Pb(II), Cu(II), Cd(II), Co(II), and Zn(II). The results indicated that PMACS had selectivity for Hg(II) sorption. The effects of various variables for sorption of Hg(II) were further explored. The maximum capacity for Hg(II) sorption was found to be 1044mgg(-1) at pH 6.0, which could compare with the maximal value of the recently reported other sorbents. The sorption followed the pseudo-second-order kinetics and Langmuir isotherm models. The rising of temperature benefited the uptake and the sorption was a spontaneous chemical process. The sorbent could be reused with EDTA. Hence, the nanomaterial would be used as a selective and high uptake sorbent in the removal of Hg(II) from effluents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. PdO/CeO2类芬顿降解酸性橙7和水杨酸的催化性能%The enhanced Fenton-like catalytic performance of PdO/CeO2 for the degradation of acid orange 7 and salicylic acid

    Institute of Scientific and Technical Information of China (English)

    葛琳; 臧成杰; 陈锋

    2015-01-01

    A PdO/CeO2 catalyst was prepared by deposition‐precipitation method and characterized with X‐ray diffraction, high‐resolution transmission electron microscopy, N2 adsorption‐desorption, X‐ray photoelectron spectroscopy and Raman spectroscopy. The results show that the Pd is pre‐sented as Pd2+in the catalyst. The interaction between the deposited PdO and CeO2 increases the Ce3+content. The catalytic activity of PdO/CeO2 was tested in the heterogeneous Fenton‐like degra‐dation of acid orange 7 (AO7) and salicylic acid (SA), both in the dark and under visible irradiation. Deposition of PdO accelerates the Fenton‐like degradation of SA, which reaches a maximum at 1.0 atom%PdO loading. A dye sensitization effect was seen with AO7 under visible irradiation. Dye sensitization promotes the regeneration of Ce3+by interfacial peroxides species through interfacial electron injection. Consequently, the combined effects of PdO loading and visible light irradiating enhanced the Fenton‐like activity to a reaction rate constant of 3.90 h–1 for the 1.0 PdO/CeO2, a ca. 50‐fold improvement.%采用沉淀-沉积法制备了PdO/CeO2催化剂,并使用X射线衍射、高分辨透射电镜、N2吸附-脱附等温线、X射线光电子能谱和Raman光谱对催化剂进行了表征.表征结果显示, Pd在复合物中以Pd2+形式存在; PdO和CeO2间的相互作用提高了CeO2中的Ce3+含量.通过酸性橙7和水杨酸的类芬顿降解考察了PdO/CeO2的多相类芬顿和可见光芬顿催化活性.结果表明, PdO沉积显著地促进了水杨酸的类芬顿降解,催化剂的PdO含量为1.0 at%时其活性最佳.染料酸性橙7在可见光照射条件下会引发染料光敏化效应.吸附的染料分子在光激发后通过界面电子注入促进了Ce3+自表面过氧物种的再生.由此, PdO负载和可见光照射的共同作用下,1.0 PdO/CeO2催化剂的酸性橙7类芬顿降解速率常数为3.90 h-1,为纯CeO2活性的50倍左右.

  9. Characteristics and biotechnology applications of aliphatic amino acid hydroxylases belonging to the Fe(II)/α-ketoglutarate-dependent dioxygenase superfamily.

    Science.gov (United States)

    Hibi, Makoto; Ogawa, Jun

    2014-05-01

    The asymmetric hydroxylation of inactive carbon atoms is still an important reaction in the industrial synthesis of valuable chiral compounds such as pharmaceuticals and fine chemicals. Applications of monooxygenation enzymes, like cytochrome P450 monooxygenases, flavin-containing monooxygenases, and Fe(II)/α-ketoglutarate-dependent dioxygenases (Fe/αKG-DOs), are strongly desired as hydroxylation biocatalysts because they have great advantages in regio- and stereoselectivity of the reactions. Recently, several novel Fe/αKG-DOs have been found to catalyze the asymmetric hydroxylation of aliphatic amino acids. Depending on their amino acid sequences, these Fe/αKG-DOs catalyze different types of regioselective hydroxylations, or C3-, C4-, and C5-hydroxylation. Additionally, most also have stereoselective sulfoxidation activities. Here, we have reviewed the characterization and process development of this novel functioning group of Fe/αKG-DOs.

  10. Reaction between the Pt(II)-complexes and the amino acids of the β-amyloid peptide

    Science.gov (United States)

    Novato, Willian T. G.; Stroppa, Pedro Henrique F.; Da Silva, Adilson D.; Botezine, Naiara P.; Machado, Flávia C.; Costa, Luiz Antônio S.; Dos Santos, Hélio F.

    2017-01-01

    Reaction between [Pt(ophen)Cl2] and HIS was monitored and the solvolysis (k1) and Cl/HIS ligand exchange (k2) rate constants obtained. The k1 and k2 were (6.2 ± 0.4) × 10-5 s-1 and 52.8 × 10-2 M-1 s-1, respectively. The corresponding calculated values were 47.5 × 10-5 s-1 and 52.2 × 10-2 M-1 s-1, in agreement with the experiment. Calculations were used to establish the reactivity order for a set of amino acids: MET ∼ LYS ∼ HIS(ε) > GLU ∼ ASP >> ASN ∼ GLN. In spite of the similar reactivity among MET, LYS and HIS, the thermodynamics suggests the reactions with LYS and HIS more favorable than with MET. Therefore, N-containing amino acids should be potential targets of Pt(II)-complexes in β-amyloid.

  11. Oral high dose ascorbic acid treatment for one year in young CMT1A patients: a randomised, double-blind, placebo-controlled phase II trial

    NARCIS (Netherlands)

    Verhamme, C.; de Haan, R.J.; Vermeulen, M.; Baas, F.; de Visser, M.; van Schaik, I.N.

    2009-01-01

    ABSTRACT: BACKGROUND: High dose oral ascorbic acid substantially improved myelination and locomotor function in a Charcot-Marie-Tooth type 1A mouse model. A phase II study was warranted to investigate whether high dose ascorbic acid also has such a substantial effect on myelination in Charcot-Marie-

  12. Synthesis, Characterization, and Interaction with Biomolecules of Platinum(II Complexes with Shikimic Acid-Based Ligands

    Directory of Open Access Journals (Sweden)

    Yan Peng

    2013-01-01

    Full Text Available Starting from the active ingredient shikimic acid (SA of traditional Chinese medicine and NH2(CH2nOH, (n=2–6, we have synthesized a series of new water-soluble Pt(II complexes PtLa–eCl2, where La–e are chelating diamine ligands with carbon chain covalently attached to SA (La–e = SA-NH(CH2nNHCH2CH2NH2; La, n=2; Lb, n=3; Lc, n=4; Ld, n=5; Le, n=6. The results of the elemental analysis, LC-MS, capillary electrophoresis, and 1H, 13C NMR indicated that there was only one product (isomer formed under the present experimental conditions, in which the coordinate mode of PtLa–eCl2 was two-amine bidentate. Their in vitro cytotoxic activities were evaluated by MTT method, where these compounds only exhibited low cytotoxicity towards BEL7404, which should correlate their low lipophilicity. The interactions of the five Pt(II complexes with DNA were investigated by agarose gel electrophoresis, which suggests that the Pt(II complexes could induce DNA alteration. We also studied the interactions of the Pt(II complexes with 5′-GMP with ESI-MS and 1H NMR and found that PtLbCl2, PtLcCl2, and PtLdCl2 could react with 5′-GMP to form mono-GMP and bis-GMP adducts. Furthermore, the cell-cycle analysis revealed that PtLbCl2, PtLcCl2 cause cell G2-phase arrest after incubation for 72 h. Overall, these water-soluble Pt(II complexes interact with DNA mainly through covalent binding, which blocks the DNA synthesis and replication and thus induces cytotoxicity that weakens as the length of carbon chain increases.

  13. Selective adsorption of Pb (II) ions by amylopectin-g-poly (acrylamide-co-acrylic acid): A bio-degradable graft copolymer.

    Science.gov (United States)

    Sasmal, Dinabandhu; Maity, Jayanta; Kolya, Haradhan; Tripathy, Tridib

    2017-04-01

    Amylopectin-g-poly (acrylamide-co-acrylic acid) [AP-g-poly (AM-co-AA)] was synthesised in water medium by using potassium perdisulphate as an initiator. The graft copolymer was characterized by molecular weight determination by size exclusion chromatography (SEC), fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, scanning electron microscope (SEM) studies, thermal analysis, measurement of neutralisation equivalent and biodegradation studies. The graft copolymer was used for Pb (II) ion removal from aqueous solution. The Pb (II) ion removal capacity of the graft copolymer was also compared with another laboratory developed graft copolymer Amylopectin-g-poly (acrylamide) (AP-g-PAM). Both the graft copolymers were also used for the competitive metal ions removal with Pb (II)/Cd (II), Pb (II)/Zn (II), Pb (II)/Ni (II), Pb (II)/Cu (II) pairs separately under similar conditions. AP-g-poly (AM-co-AA) showed better Pb (II) ion adsorbing power over AP-g-PAM and also much selective towards Pb (II) ions. The adsorption follows a second order rate equation and Langmuir isotherm model.

  14. Sources and sinks of formic, acetic, and pyruvic acids over central Amazonia. II - Wet season

    Science.gov (United States)

    Talbot, R. W.; Andreae, M. O.; Berresheim, H.; Jacob, D. J.; Beecher, K. M.

    1990-01-01

    Potential sources and sinks of formic, acetic, and pyruvic acids over the Amazon forest were investigated using a photochemical model and data collected on gas phase concentrations of these acids in the forest canopy, boundary layer, and free troposphere over the central Amazon Basin during the 1987 wet season. It was found that the atmospheric reactions previously suggested in the literature as sources of carboxylic acids (i.e., the gas phase decomposition of isoprene, the reaction between CH3CO3 and a peroxide, and aqueous phase oxidation of CH2O) appear to be too slow to explain the observed concentrations, suggesting that other atmospheric reactions, so far unidentified, could make a major contribution to the carboxylic acid budgets.

  15. Haloacetic acids in the aquatic environment. Part II: ecological risk assessment.

    Science.gov (United States)

    Hanson, Mark L; Solomon, Keith R

    2004-08-01

    Haloacetic acids (HAAs) are environmental contaminants found in aquatic ecosystems throughout the world as a result of both anthropogenic and natural production. The ecological risk posed by these compounds to organisms in freshwater environments, with a specific focus on aquatic macrophytes, was characterized. The plants evaluated were Lemna gibba, Myriophyllum spicatum and M. sibiricum and the HAAs screened were monochloroacetic acid (MCA), dichloroacetic acid (DCA), trichloroacetic acid (TCA), trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CDFA). Laboratory toxicity data formed the basis of the risk assessment, but field studies were also utilized. The estimated risk was calculated using hazard quotients (HQ), as well as effect measure distributions (EMD) in a modified probabilistic ecological risk assessment. EMDs were used to estimate HAA thresholds of toxicity for use in HQ assessments. This threshold was found to be a more sensitive measure of low toxicity than the no observed effect concentrations (NOEC) or the effective concentration (EC10). Using both deterministic and probabilistic methods, it was found that HAAs do not pose a significant risk to freshwater macrophytes at current environmental concentrations in Canada, Europe or Africa for both single compound and mixture exposures. Still, HAAs are generally found as mixtures and their potential interactions are not fully understood, rendering this phase of the assessment uncertain and justifying further effects characterization. TCA in some environments poses a slight risk to phytoplankton and future concentrations of TFA and CDFA are likely to increase due to their recalcitrant nature, warranting continued environmental surveillance of HAAs.

  16. 21 CFR 146.146 - Frozen concentrated orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen concentrated orange juice. 146.146 Section... (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.146 Frozen concentrated orange juice. (a) Frozen concentrated orange...

  17. 21 CFR 146.151 - Orange juice for manufacturing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Orange juice for manufacturing. 146.151 Section... Fruit Juices and Beverages § 146.151 Orange juice for manufacturing. (a) Orange juice for manufacturing is the food prepared for further manufacturing use. It is prepared from unfermented juice obtained...

  18. 21 CFR 146.153 - Concentrated orange juice for manufacturing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Concentrated orange juice for manufacturing. 146... Canned Fruit Juices and Beverages § 146.153 Concentrated orange juice for manufacturing. (a) Concentrated orange juice for manufacturing is the food that complies with the requirements of composition and label...

  19. Two new Zn(II) coordination polymers based on mixed pipemidic acid and flexible aromatic dicarboxylic acid ligands: Syntheses, crystal structures and luminescent properties

    Science.gov (United States)

    Jia, Yanxia; Zhou, Pingping

    2016-09-01

    Two new Zn(II) coordination polymers, namely [Zn(4,4‧-sdb) (HPPA)]n (1) and [Zn(2,2‧-bpdc)0.5(PPA)]n (2) (4,4‧-H2sdb = 4,4‧-sulfonyldibenzoate, 2,2‧-H2bpdc = 2,2‧-biphenyldicarboxylic acid, HPPA = pipemidic acid) were successfully obtained under hydrothermal conditions. These two compounds were further characterized by single-crystal X-ray diffraction analyses, elemental analyses, powder X-ray diffraction (PXRD) analyses and IR spectra. Compound 1 features a 1D chain structure, which further extended into a 3D supramolecular framework via intermolecular hydrogen bonds and weak van der Waals interactions, and compound 2 features a 3D framework with 6-connected α-Po-type topology. The structural regulation for these two compounds was successfully achieved by changing the flexible aromatic dicarboxylic acid ligand. Moreover, the thermal stabilities and luminescent properties for these two compounds were also investigated.

  20. The nomenclature of the Orang Utan

    NARCIS (Netherlands)

    Groves, C.P.; Holthuis, L.B.

    1985-01-01

    Changes in the nomenclature of the Orang Utan recently proposed by Röhrer-Ertl are shown to be unnecessary. The generic name Pongo Van Wurmb, 1784, for the genus, P.s. satyrus Linnaeus, 1758, for the Sumatran subspecies, and P.s. borneensis Van Wurmb, 1784, for the Bornean subspecies, as used by Röh

  1. The nomenclature of the Orang Utan

    NARCIS (Netherlands)

    Groves, C.P.; Holthuis, L.B.

    1985-01-01

    Changes in the nomenclature of the Orang Utan recently proposed by Röhrer-Ertl are shown to be unnecessary. The generic name Pongo Van Wurmb, 1784, for the genus, P.s. satyrus Linnaeus, 1758, for the Sumatran subspecies, and P.s. borneensis Van Wurmb, 1784, for the Bornean subspecies, as used by Röh

  2. The nomenclature of the Orang Utan

    NARCIS (Netherlands)

    Groves, C.P.; Holthuis, L.B.

    1985-01-01

    Changes in the nomenclature of the Orang Utan recently proposed by Röhrer-Ertl are shown to be unnecessary. The generic name Pongo Van Wurmb, 1784, for the genus, P.s. satyrus Linnaeus, 1758, for the Sumatran subspecies, and P.s. borneensis Van Wurmb, 1784, for the Bornean subspecies, as used by

  3. Mycorrhiza alters the profile of root hairs in trifoliate orange.

    Science.gov (United States)

    Wu, Qiang-Sheng; Liu, Chun-Yan; Zhang, De-Jian; Zou, Ying-Ning; He, Xin-Hua; Wu, Qing-Hua

    2016-04-01

    Root hairs and arbuscular mycorrhiza (AM) coexist in root systems for nutrient and water absorption, but the relation between AM and root hairs is poorly known. A pot study was performed to evaluate the effects of four different AM fungi (AMF), namely, Claroideoglomus etunicatum, Diversispora versiformis, Funneliformis mosseae, and Rhizophagus intraradices on root hair development in trifoliate orange (Poncirus trifoliata) seedlings grown in sand. Mycorrhizal seedlings showed significantly higher root hair density than non-mycorrhizal seedlings, irrespective of AMF species. AMF inoculation generally significantly decreased root hair length in the first- and second-order lateral roots but increased it in the third- and fourth-order lateral roots. AMF colonization induced diverse responses in root hair diameter of different order lateral roots. Considerably greater concentrations of phosphorus (P), nitric oxide (NO), glucose, sucrose, indole-3-acetic acid (IAA), and methyl jasmonate (MeJA) were found in roots of AM seedlings than in non-AM seedlings. Levels of P, NO, carbohydrates, IAA, and MeJA in roots were correlated with AM formation and root hair development. These results suggest that AMF could alter the profile of root hairs in trifoliate orange through modulation of physiological activities. F. mosseae, which had the greatest positive effects, could represent an efficient AM fungus for increasing fruit yields or decreasing fertilizer inputs in citrus production.

  4. Fermented orange juice: source of higher carotenoid and flavanone contents.

    Science.gov (United States)

    Escudero-López, Blanca; Cerrillo, Isabel; Herrero-Martín, Griselda; Hornero-Méndez, Damaso; Gil-Izquierdo, Angel; Medina, Sonia; Ferreres, Federico; Berná, Genoveva; Martín, Francisco; Fernández-Pachón, Maria-Soledad

    2013-09-18

    The intake of bioactive compounds and moderate alcohol decreases the risk of cardiovascular diseases. These effects could be joined in a beverage created by a controlled alcoholic fermentation of orange juice. The influence of controlled alcoholic fermentation on the bioactive compound profile of orange juice has not been previously evaluated, and this is the purpose of the present study. Total and individual flavanones and carotenoids significantly increased throughout the fermentation. The reason for this was an enhanced extraction of these compounds from the pulp. Besides, the potential bioavailability of flavanones increased due to a higher content of hesperetin-7-O-glucoside (2-fold higher at the end of the fermentation process). Ascorbic acid did not undergo a significant change, and only total phenolics decreased. Antioxidant capacity was also evaluated. TEAC and FRAP values remained constant throughout the process. However, ORAC and DPPH values significantly increased. Correlation analysis concluded that the increase in ORAC and DPPH values could be due to enhancement of flavanones.

  5. Phosphorus Recovery Using Zirconium-Loaded Saponified Orange Juice Residue

    Science.gov (United States)

    Harada, Hiroyuki; Kondo, Mitsunori; Biswas, Biplob K.; Ohura, Seichirou; Inoue, Katsutoshi; Ishikawa, Susumu; Kawakita, Hidetaka; Ohto, Keisuke

    Zirconium was immobilized to orange juice residue, to investigate the feasibility of using zirconium-loaded saponified orange juice residue (Zr-SOJR) for phosphorus recovery from secondary effluent and the extraction solution from incinerated sewage sludge ash by using H2SO4 and HCl. These had phosphorus concentrations of 68.2 mg/dm3 and 5.9 mg/dm3, respectively. The phosphorus removal rate secondary effluent increased with an increasing solid/liquid ratio in batch experiments. The adsorption capacity of Zr-SOJR was also compared with those obtained using a synthetic phosphorus solution and using zirconium-loaded ferrite. The prepared absorbent was effective for phosphorus removal and exhibited a reasonably high sorption capacity, twice that of zirconium ferrite. Secondary effluent was treated by packed column, and this reached break-through after 300 bed volumes. The results from phosphorous extraction from the ash indicate that can be treated with acid to efficiently recover phosphorous and thus can be absorbed by Zr-SOJR.

  6. 6-Hydroxypelargonidin glycosides in the orange-red flowers of Alstroemeria.

    Science.gov (United States)

    Tatsuzawa, Fumi; Saito, Norio; Murata, Naho; Shinoda, Koichi; Shigihara, Atsushi; Honda, Toshio

    2003-04-01

    Two 6-hydroxypelargonidin glycosides were isolated from the orange-red flowers of Alstroemeria cultivars, and determined to be 6-hydroxypelargonidin 3-O-(beta-D-glucopyranoside) and 3-O-[6-O-(alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside], respectively, by chemical and spectroscopic methods. In addition, five known anthocyanidin glycosides, 6-hydroxycyanidin 3-malonylglucoside, 6-hydroxycyanidin 3-rutinoside, cyanidin 3-malonylglucoside, cyanidin 3-rutinoside and pelargonidin 3-rutinoside were identified in the flowers.

  7. 2-Octadecynoic acid as a dual life stage inhibitor of Plasmodium infections and plasmodial FAS-II enzymes.

    Science.gov (United States)

    Carballeira, Néstor M; Bwalya, Angela Gono; Itoe, Maurice Ayamba; Andricopulo, Adriano D; Cordero-Maldonado, María Lorena; Kaiser, Marcel; Mota, Maria M; Crawford, Alexander D; Guido, Rafael V C; Tasdemir, Deniz

    2014-09-01

    The malaria parasite Plasmodium goes through two life stages in the human host, a non-symptomatic liver stage (LS) followed by a blood stage with all clinical manifestation of the disease. In this study, we investigated a series of 2-alkynoic fatty acids (2-AFAs) with chain lengths between 14 and 18 carbon atoms for dual in vitro activity against both life stages. 2-Octadecynoic acid (2-ODA) was identified as the best inhibitor of Plasmodium berghei parasites with ten times higher potency (IC50=0.34 μg/ml) than the control drug. In target determination studies, the same compound inhibited three Plasmodium falciparum FAS-II (PfFAS-II) elongation enzymes PfFabI, PfFabZ, and PfFabG with the lowest IC50 values (0.28-0.80 μg/ml, respectively). Molecular modeling studies provided insights into the molecular aspects underlying the inhibitory activity of this series of 2-AFAs and a likely explanation for the considerably different inhibition potentials. Blood stages of P. falciparum followed a similar trend where 2-ODA emerged as the most active compound, with 20 times less potency. The general toxicity and hepatotoxicity of 2-AFAs were evaluated by in vitro and in vivo methods in mammalian cell lines and zebrafish models, respectively. This study identifies 2-ODA as the most promising antiparasitic 2-AFA, particularly towards P. berghei parasites.

  8. Preparation and characterization of poly(maleic acid)-grafted cross-linked chitosan microspheres for Cd(II) adsorption.

    Science.gov (United States)

    Yu, Zhenzhen; Dang, Qifeng; Liu, Chengsheng; Cha, Dongsu; Zhang, Haifeng; Zhu, Wenjing; Zhang, Qianqian; Fan, Bing

    2017-09-15

    A novel adsorbent, composed of poly(maleic acid)-grafted cross-linked chitosan microspheres (PMACCMs), was prepared via cross-linking with glutaraldehyde and modification by grafting maleic acid. FTIR, zeta potential, elemental analysis, (13)C NMR, DTG, laser particle size analysis, SEM, and BET methods were applied to characterize PMACCMs, exhibiting a successful fabrication, good thermostability, and well-defined surface microstructure beneficial to Cd(II) adsorption. The effects of pH, contact time, and initial concentration on Cd(II) adsorption were also investigated, and the maximum adsorption capacity was 39.2mgg(-1), indicating a great improvement as compared with that (14.5mgg(-1)) of cross-linked chitosan microspheres. The experimental data were well fitted with pseudo-second-order kinetic and Langmuir isotherm models. Five-cycle reusability tests demonstrated PMACCMs could be repeatedly used with a small adsorption capacity loss (<15%). Additionally, the adsorption mechanism was proposed. All the results confirmed that PMACCMs, which presented outstanding adsorption capability and reusability, could be a good candidate for wastewater purification. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Effect of temperature and some added compounds on the stability of blood orange marmalade.

    Science.gov (United States)

    Licciardello, Fabio; Muratore, Giuseppe

    2011-09-01

    Jams and marmalades are often wrongly believed to be stable products, as the degradation of pigments such as anthocyanins, browning reactions, and the formation of sugar degradation products may occur during storage. The paper aims at studying some of the degradation reactions occurring in blood orange marmalade stored at 20 °C and 35 °C. The addition of natural (tea extract) and naturally occurring (ascorbic acid, cysteine, gallic acid) compounds to marmalade was addressed at investigating the possible effect on retarding such phenomena. Results highlight the dependence of anthocyans and 5-hydroxymethyl-2-furaldehyde (HMF) levels on the storage temperature. Marmalades added with cysteine, unlike the samples added with phenol compounds, showed higher anthocyans and lower HMF levels just after processing, together with a reduced anthocyan loss kinetics and a slowdown of HMF formation during storage at both temperatures. Transformation of blood oranges into marmalade represents an alternative to fresh market in periods when the high availability of the citrus causes the collapse of prices. Blood orange marmalade is characterized by a high nutritional value, however, it is not widely distributed yet. Its storability is limited by color and organoleptic changes that influence consumers' acceptance. The optimization of blood orange marmalade preparation could help producers improve storability and widen distribution. © 2011 Institute of Food Technologists®

  10. Electrolytic Treatment of Simulative Wastewater Containing Acid Orange 7 Using a Three-phase Three-dimensional Electrode Reactor%三相三维电极反应器电解处理酸性橙7模拟废水研究

    Institute of Scientific and Technical Information of China (English)

    徐丽娜; 石绍渊; 赵华章; 孔江涛; 倪晋仁

    2007-01-01

    采用三相三维电极反应器对酸性橙7(Acid Orange 7,AO7)模拟废水进行电解处理实验研究.结果表明,在连续5次实验后,AO7模拟废水在该体系中可以达到稳定的处理效果,且线性拟合数据表明脱色率、CODcr和TOC去除率均能较好地符合一级动力学规律.与二维电极体系相比,三相三维电极体系有利于H2O2类电化学活性物质的生成,因而具有更好的处理效果,其脱色率和CODcr去除率均可提高30%以上.通过UV-Vis法对AO7在三相三维体系电解过程中的变化进行分析,初步探讨了其降解机理.

  11. Rapid removal of Ni(II from aqueous solution using 3-Mercaptopropionic acid functionalized bio magnetite nanoparticles

    Directory of Open Access Journals (Sweden)

    Sada Venkateswarlu

    2015-12-01

    Full Text Available The surfaces of bio magnetite nanoparticles were functionalized with 3-Mercaptopropionic acid (3 MPA and used as a high-capacity and recyclable adsorbent for the rapid removal of Ni(II from aqueous solution. The 3 MPA@Fe3O4 MNPs were characterized by Fourier transformed infrared analysis (FT-IR, transmission electron microscopy (TEM, energy dispersive X-ray spectroscopy (EDS and vibrating sample magnetometer (VSM analysis. This 3 MPA@Fe3O4 MNPs have been used for removal of Ni(II from aqueous solution. The hysteresis loops of 3 MPA@Fe3O4 MNPs shows an excellent ferromagnetic behavior with saturation magnetization value of 14.02 emu/g. The adsorption isotherm data were fitted well to Langmuir isotherm, the monolayer adsorption capacity was found to be 42.01 mg/g at 303 K. The experimental kinetic data fitted very well the pseudo-second-order model.The results indicate that the biogenic 3 MPA@Fe3O4 MNPs act as significant adsorbent material for removal of Ni(II aqueous solution and also considered as a potential adsorbent for hazardous metal ions from wastewater.

  12. Photostability of natural orange-red and yellow fungal pigments in liquid food model systems.

    Science.gov (United States)

    Mapari, Sameer A S; Meyer, Anne S; Thrane, Ulf

    2009-07-22

    The variation in the photostability among the currently authorized natural pigments limits their application span to a certain type of food system, and more robust alternatives are being sought after to overcome this problem. In the present study, the photostability of an orange-red and a yellow fungal pigment extract produced by ascomycetous fungi belonging to the genera Penicillium and Epicoccum , respectively, were studied in a soft drink model medium and in citrate buffer at low and neutral pH. The quantitative and qualitative color change pattern of the fungal pigment extracts indicated an enhanced photostability of fungal pigment extracts compared to the commercially available natural colorants Monascus Red and turmeric used as controls. Yellow components of the orange-red fungal pigment extract were more photostable than the red components. Chemistry of the photodegradation of the orange-red pigment extract was studied by high-performance liquid chromatography-diode array detection-mass spectrometry (HPLC-DAD-MS), and a light-induced formation of a structural analogue of sequoiamonascin C, a Monascus -like polyketide pigment discovered in the extract of Penicillium aculeatum IBT 14263 on yeast extract sucrose (YES) medium, was confirmed in the soft drink medium at pH 7.

  13. Treatment of iron(II)-rich acid mine water with limestone and oxygen.

    Science.gov (United States)

    Mohajane, G B; Maree, J P; Panichev, N

    2014-01-01

    The main components of acid mine water are free acid, sulphate, and Fe²⁺. Limestone is the most cost-effective alkali that can be used for neutralization. The purpose of this investigation was to identify conditions where Fe²⁺ is removed with limestone and simultaneously oxidized with oxygen to Fe³⁺, in a polyvinyl chloride pipe under pressure. Gypsum scaling is prevented by passing rubber balls through the pipe of the so-called Oxygen-Pipe-Neutralization (OPeN) process pilot plant. Two synthetic waters were treated: (A) acid mine water containing 123 mg L⁻¹ Fe²⁺ representing gold mine water, and (B) acid mine water containing 6,032 mg L⁻¹ Fe²⁺ representing coal mine water. Batch studies were carried out in a pipe reactor and showed that the rate of Fe²⁺ oxidation depended on the Fe²⁺ concentration, oxygen pressure, amount of recycled sludge, limestone dosage and the mixing rate. Continuous studies in an OPeN process pilot plant resulted in 100% removal of total acidity from synthetic coal mine water and a 98% removal from synthetic gold mine water. Fe²⁺ was removed completely as precipitated Fe(OH)₃ from both synthetic coal and gold mine water at around pH 7 at 200 and 100 kPa oxygen pressure, respectively.

  14. Fe-Zn-Al-柱撑蒙脱石催化剂的制备及其降解酸性橙II性能%Fe-Zn-Al Pillared Montmorillonite for Catalytic Wet Peroxide Oxidation Degradation of Orange Acid II:Preparation Methods and Properties

    Institute of Scientific and Technical Information of China (English)

    牛露; 赵彬侠; 叶维; 邱爽; 关文斌; 刘楠; 张小里

    2016-01-01

    以铁为活性组分,钙基蒙脱石为载体,分别采用传统法、超声和微波辅助法制备了Fe-Zn-Al-柱撑蒙脱石(Fe-Zn-Al-Mt)系列催化剂。表征了催化剂的结构和表面性能,研究了不同Fe/Zn摩尔比、焙烧温度以及制备方法对催化剂性能的影响;并将该催化剂用于催化湿式过氧化氢氧化法(CWPO)降解酸性橙II (OII)染料废水。结果表明:采用Fe/Zn摩尔比为3/7、焙烧温度为500℃、微波辅助制备的Fe-Zn-Al-Mt催化剂在蒙脱石表面形成更多的活性组分(ZnFe2O4纳米粒子),用于CWPO降解OII染料废水时效果最佳,其中色度和化学需氧量(COD)去除率可分别高达99.9%和79.7%,Fe离子溶出量仅为0.27 mg/L。此外,微波辅助制备的Fe-Zn-Al(3/7)-Mt催化剂重复使用5次,均能使废水褪色,COD去除率仅降低了3.1%,总Fe离子溶出仅为0.42 mg/L。表明Fe-Zn-Al-Mt催化剂用于降解OII染料废水时具有较高的催化活性和稳定性。%A series of Fe-Zn-Al-pillared montmorillonite (Mt) catalysts were prepared by three preparation methods (i.e. conventional method, ultrasonic and microwave treatment methods). The structure and surface properties of the (Fe-Zn-Al-Mt) catalysts were characterized. Effects of Fe/Zn molar ratio, calcinated temperature and preparation method on the catalytic performance of Fe-Zn-Al-Mt catalysts were investigated. The prepared catalysts were used for the degradation of Orange II (OII) by a catalytic wet hydrogen peroxide oxidation (CWPO) method. The results show that the catalyst prepared by microwave treatment at Fe/Zn more ratio of 3/7 and calcinated temperature of 500℃ contains more active ingredient (ZnFe2O4 nanoparticles) and exhibits the optimum degradation performance (i.e., degradation of 99.9%, chemical oxygen demand(COD) reduction of 79.7%, and Fe leaching was only 0.27mg/L). Besides, Fe-Zn-Al(3/7)-Mt(500℃) catalyst prepared by microwave treatment method could be reused for

  15. The Chemical and Educational Appeal of the Orange Juice Clock

    Science.gov (United States)

    Kelter, Paul B.; Carr, James D.; Johnson, Tanya; Mauricio Castro-Acuña, Carlos

    1996-12-01

    The Orange Juice Clock, in which a galvanic cell is made from the combination of a magnesium strip, a copper strip, and juice in a beaker, has been a popular classroom, conference, and workshop demonstration for nearly 10 years. It is widely enjoyed because it shows visually how chemistry - or more precisely, electrochemistry - is responsible for the very common phenomenon of a clock ticking. The chemistry of the process can also be understood on a variety of levels, from middle school (simple electron flow in a circuit, Ohm's law) and high school (reduction/oxidation and standard cell potentials) to first-year college (cell potential at nonideal conditions) and graduate school courses (overpotential and charge transfer across interfaces.) The discussion that follows considers the recent history, chemistry, and educational uses of the demonstration. The History The demonstration was devised by one of us (PK) in 1986, after reading an activity in Hubert Alyea's 1947 compendium of chemical demonstrations from this Journal (1). In that activity, Alyea hooked a magnesium strip to the negative battery terminal of an electric bell and hooked a copper strip to the positive terminal. He placed the loose ends of the strips into a 1M 2SO4 solution and the bell rang. After trying the demonstration, it seemed to make sense to modify the electrolyte to orange juice because it is safe, readily available, and would be a mixture in which the magnesium would oxidize more slowly than in sulfuric acid. Further, a clock was substituted for the bell because a clock is easier on the ears than a bell. A video of the orange-juice clock setup is given as Figure 1. Figure 1.The orange juice clock set up. Video of orange juice clock was filmed and editted by Jerry Jacobson at the University of Wisconsin - Madison. The apparatus was presented in 1987 as part of a teacher workshop led by Irwin Talesnick, then of Queen's University in Canada. Talesnick, whose distinguished career has been

  16. In vitro bioaccessibility of carotenoids, flavonoids, and vitamin C from differently processed oranges and orange juices [Citrus sinensis (L.) Osbeck].

    Science.gov (United States)

    Aschoff, Julian K; Kaufmann, Sabrina; Kalkan, Onur; Neidhart, Sybille; Carle, Reinhold; Schweiggert, Ralf M

    2015-01-21

    Carotenoid, flavonoid, and vitamin C concentrations were determined in fresh orange segments and a puree-like homogenate derived thereof, as well as freshly squeezed, flash-pasteurized, and pasteurized juices. Lutein and β-cryptoxanthin were slightly degraded during dejuicing, whereas β-carotene levels were retained. Vitamin C levels remained unaffected, whereas flavonoid levels decreased 8-fold upon juice extraction, most likely due to the removal of flavonoid-rich albedo and juice vesicles. Likewise, the presence of such fibrous matrix compounds during in vitro digestion was assumed to significantly lower the total bioaccessibility (BA) of all carotenoids from fresh fruit segments (12%) as compared to juices (29-30%). Mechanical disruption of orange segments prior to digestion did not alter carotenoid BA, whereas pasteurization of the freshly squeezed juice slightly increased BA by 9-11%. In addition to carotenoid BA, the stabilities of hesperidin, narirutin, and vitamin C including dehydroascorbic acid during in vitro digestion were monitored, and applied analytical methods were briefly validated.

  17. A solid-state sensor based on ruthenium (II) complex immobilized on polytyramine film for the simultaneous determination of dopamine, ascorbic acid and uric acid

    Energy Technology Data Exchange (ETDEWEB)

    Khudaish, Emad A., E-mail: ejoudi@squ.edu.om [Sultan Qaboos University, College of Science, Chemistry Department, PO Box 36, PC 123 Muscat (Oman); Al-Ajmi, Khawla Y. [Sultan Qaboos University, College of Science, Chemistry Department, PO Box 36, PC 123 Muscat (Oman); Al-Harthi, Salim H. [Sultan Qaboos University, College of Science, Department of Physics, PO Box 36, PC 123 Muscat (Oman)

    2014-08-01

    A solid-state sensor based on a polytyramine (Pty) film deposited on a glassy carbon electrode doped with a tris(2,2′-bipyridyl)Ru(II) complex (Ru/Pty/GCE) was constructed electrochemically. The surface morphology of the film modified electrode was characterized using electrochemical and surface scanning techniques. A redox property represented by a [Ru(bpy){sub 3}]{sup 3+/2+} couple immobilized at the Pty moiety was characterized using typical voltammetric techniques. A distinct Ru 3d peak obtained at 280.9 eV confirms doping of the Ru species onto the Pty moiety characterized by X-ray photoelectron (XPS). Atomic force microscopy (AFM) images demonstrate that incorporation of Ru decreases the surface roughness of the native Pty film modified electrode. The Ru/Pty/GCE exhibits efficient electrochemical sensing toward the oxidation of dopamine (DA), ascorbic acid (AA) and uric acid (UA) in their mixture. Three well-defined peaks were resolved with a large peak to peak separation and the detection limits of AA, DA and UA are brought down to 0.31, 0.08 and 0.58 μM, respectively. Interference studies and application for DA determination in real samples were conducted with satisfactory results. - Highlights: • XPS data confirm doping of ruthenium onto the polytyramine moiety. • The voltammetric signals of ascorbic acid, dopamine and uric acid are well defined. • The sensor is stable and offers a large adsorption facility for all species. • The sensor is highly sensitive to dopamine oxidation. • The sensor is applied to a real sample with a satisfactory recovery percentage.

  18. Effect of Alkali Treatment of Wheat Straw on Adsorption of Cu(II under Acidic Condition

    Directory of Open Access Journals (Sweden)

    Yiping Guo

    2016-01-01

    Full Text Available The convenient and feasible pretreatment method of alkali treatment is very common in the degradation process of wheat straw. However, its utilization in the pretreatment of wheat straw as alternative adsorbents for aqueous heavy metals remediation is rarely reported. The present study investigated the removal efficiency of Cu(II ions using wheat straw with alkali pretreatment. The condition of alkali treatment on wheat straw was optimized with the adsorption capacity of Cu(II as indicator using single-factor experiments. The influences of wheat straw dosages, pH values, contact time, and temperatures on adsorption performance for both untreated wheat straw (UWS and alkali-treated wheat straw (AWS were investigated. Results showed that the relatively large removal rate of Cu(II could be obtained, and chemical behavior occurred during the adsorption process. Characteristic analysis found that the major function of alkali treatment to wheat straw was to introduce the hydroxy group, which resulted in the increase of -C-O- group. Although the adsorption capacity is not as high as the one of ligands supported adsorbents, the method is easy to operate and has a wide range of application; at the same time, it could realize both purposes of treating heavy metal pollution and solid wastes.

  19. Rapid degradation of azo dye methyl orange using hollow cobalt nanoparticles.

    Science.gov (United States)

    Sha, Yingying; Mathew, Iswarya; Cui, Qingzhou; Clay, Molly; Gao, Fan; Zhang, Xiaoqi Jackie; Gu, Zhiyong

    2016-02-01

    A rapid and efficient method for methyl orange degradation using hollow cobalt (Co) nanoparticles is reported. Hollow Co nanoparticles were fabricated by a galvanic replacement reaction using aluminum (Al) nanoparticles as the template material. The methyl orange degradation characteristics were investigated by measuring the time dependent UV-Vis absorption of the dye solution, which showed a very fast degradation rate under acidic conditions. At an initial methyl orange concentration of 100 mg/L (pH = 2.5) and Co nanoparticle dosage of 0.5 g/L, the azo dye degradation efficiency reached up to 99% within 4 min, and the degradation constant rate was up to 2.444 min(-1), which is the highest value among other studies. A comparison of the decolorization rates at similar conditions with several other azo dyes, including Congo red, Amaranth, and Orange G, showed that the dye with a simpler structure and lower molecular mass decolorized considerably faster than the ones having a more complicated structure (higher molecular mass). The methyl orange degradation was also conducted using hollow nickel (Ni) nanoparticles and commercially available solid spherical Co and Ni nanoparticles. The results showed that Co-based nanoparticles outperformed Ni-based nanoparticles, with the hollow Co nanoparticles exhibiting the fastest degradation rate. Using the hollow Co nanoparticles is a very promising approach for the remediation of methyl orange dye containing wastewater due to the fast degradation rate and high degradation efficiency. In addition, these hollow Co nanoparticles are easily recycled because of their magnetic property.

  20. Phosphatidylcholine is a major source of phosphatidic acid and diacylglycerol in angiotensin II-stimulated vascular smooth-muscle cells.

    Science.gov (United States)

    Lassègue, B; Alexander, R W; Clark, M; Akers, M; Griendling, K K

    1993-06-01

    In cultured vascular smooth-muscle cells, angiotensin II produces a sustained formation of diacylglycerol (DG) and phosphatidic acid (PtdOH). Since the fatty acid composition of these molecules is likely to determine their efficacy as second messengers, it is important to ascertain the phospholipid precursors and the biochemical pathways from which they are produced. Our experiments suggest that phospholipase D (PLD)-mediated phosphatidylcholine (PtdCho) hydrolysis is the major source of both DG and PtdOH during the late signalling phase. First, in cells labelled with [3H]myristate, which preferentially labels PtdCho, formation of [3H]PtdOH precedes formation of [3H]DG. Second, in contrast with phospholipase C (PLC) activation, DG mass accumulation is dependent on extracellular Ca2+. Similarly, DG mass accumulation is not attenuated by protein kinase C activation, which we have previously shown to inhibit the phosphoinositide-specific PLC. Third, the fatty acid composition of late-phase DG and PtdOH more closely resembles that of PtdCho than that of phosphatidylinositol. Finally, in cells labelled for a short time with [3H]glycerol, the radioactivity incorporated into [3H]DG and PtdOH was greater than that incorporated into PtdIns, but not into PtdCho. We found no evidence that synthesis de novo or phosphatidylethanolamine breakdown contributes to sustained DG and PtdOH formation. Thus, in angiotensin II-stimulated cultured vascular smooth-muscle cells, PLD-mediated PtdCho hydrolysis is the major source of sustained DG and PtdOH, whereas phosphoinositide breakdown is a minor contributor. Furthermore, PtdOH phosphohydrolase, which determines the relative levels of DG and PtdOH, appears to be regulated by protein kinase C. These results have important implications for the role of these second messengers in growth and contraction.

  1. Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases; Part 1: alkyl halide alkylations.

    Science.gov (United States)

    Sorochinsky, Alexander E; Aceña, José Luis; Moriwaki, Hiroki; Sato, Tatsunori; Soloshonok, Vadim A

    2013-10-01

    Alkylations of chiral or achiral Ni(II) complexes of glycine Schiff bases constitute a landmark in the development of practical methodology for asymmetric synthesis of α-amino acids. Straightforward, easy preparation as well as high reactivity of these Ni(II) complexes render them ready available and inexpensive glycine equivalents for preparing a wide variety of α-amino acids, in particular on a relatively large scale. In the case of Ni(II) complexes containing benzylproline moiety as a chiral auxiliary, their alkylation proceeds with high thermodynamically controlled diastereoselectivity. Similar type of Ni(II) complexes derived from alanine can also be used for alkylation providing convenient access to quaternary, α,α-disubstituted α-amino acids. Achiral type of Ni(II) complexes can be prepared from picolinic acid or via recently developed modular approach using simple secondary or primary amines. These Ni(II) complexes can be easily mono/bis-alkylated under homogeneous or phase-transfer catalysis conditions. Origin of diastereo-/enantioselectivity in the alkylations reactions, aspects of practicality, generality and limitations of this methodology is critically discussed.

  2. Parental Dominant Inheritance of Fruit Carotenoids, Sugars and Organic Acids in a Citrus Interspecific Allotetraploid Somatic Hybrid Between Bonnaza Navel Orange and Rough Lemon%脐橙与粗柠檬体细胞杂种果实类胡萝卜素、糖酸遗传的亲本偏向性

    Institute of Scientific and Technical Information of China (English)

    郑蓓蓓; 谢宗周; 郭文武

    2013-01-01

    Carotenoid compounds in the fruit pulp of somatic hybrid [‘Bonnaza’ naval orange (Citrus sinensis Osbeck) + rough lemon (C.jambhiri Lush)] and both parental species were quantitatively evaluated by HPLC,sugars and organic acids content were investigated by GC,and Real-time RT-PCR was used to detect expression levels of key genes involved in the carotenoid,sugars and organic acids biosynthetic pathways.Results revealed that strong dominance of rough lemon was found for citric acid,malic acid and carotenoid compound in somatic hybrid fruit,while sucrose content showed mid-parent value.Gene expression was higher in navel orange than in rough lemon for four of seven genes analyzed involved in carotenoid biosynthetic pathway.Rough lemon dominance was observed for expression of CitCrt,CitLcy-e and CitZep.These results indicated that rough lemon played a dominant role in inheritance of fruit quality characteristics and gene expression in the somatic hybrid.%采用高效液相色谱测定柑橘种间体细胞杂种[‘朋娜’脐橙(Citrus sinensis Osbeck)+粗柠檬(C.jambhiri Lush)]和其两个融合亲本果实的类胡萝卜素含量,气相色谱测定可溶性糖及有机酸含量,并检测代谢过程中关键基因的表达,比较分析体细胞杂种果实品质遗传及基因表达特点.结果表明,体细胞杂种类胡萝卜素成分及含量均偏向粗柠檬亲本,柠檬酸、苹果酸积累量也偏向粗柠檬;而蔗糖含量处在中亲值;实时定量PCR技术检测类胡萝卜素代谢途径中的7个基因,其中4个基因在‘朋娜’脐橙中的表达量高于粗柠檬,环化途径中番茄红素£环化酶基因(CitLcy-e)、玉米黄质环氧酶基因(CitZep)在体细胞杂种中表达量偏向粗柠檬亲本,显著低于‘朋娜’脐橙.可见粗柠檬遗传物质的表达在体细胞杂种中占主导地位.

  3. Effect of thermal processing on the profile of bioactive compounds and antioxidant capacity of fermented orange juice.

    Science.gov (United States)

    Escudero-López, Blanca; Cerrillo, Isabel; Gil-Izquierdo, Ángel; Hornero-Méndez, Dámaso; Herrero-Martín, Griselda; Berná, Genoveva; Medina, Sonia; Ferreres, Federico; Martín, Franz; Fernández-Pachón, María-Soledad

    2016-11-01

    Previously, we reported that alcoholic fermentation enhanced flavanones and carotenoids content of orange juice. The aim of this work was to evaluate the influence of pasteurization on the qualitative and quantitative profile of bioactive compounds and the antioxidant capacity of fermented orange juice. Ascorbic acid (203 mg/L), total flavanones (647 mg/L), total carotenoids (7.07 mg/L) and provitamin A (90.06 RAEs/L) values of pasteurized orange beverage were lower than those of fermented juice. Total phenolic remained unchanged (585 mg/L) and was similar to that of original juice. The flavanones naringenin-7-O-glucoside, naringenin-7-O-rutinoside, hesperetin-7-O-rutinoside, hesperetin-7-O-glucoside and isosakuranetin-7-O-rutinoside, and the carotenoids karpoxanthin and isomer, neochrome, lutein, ζ-carotene, zeaxanthin, mutatoxanthin epimers, β-cryptoxanthin and auroxanthin epimers were the major compounds. Pasteurization produced a decrease in antioxidant capacity of fermented juice. However, TEAC (5.45 mM) and ORAC (6353 μM) values of orange beverage were similar to those of original orange juice. The novel orange beverage could be a valuable source of bioactive compounds with antioxidant capacity and exert potential beneficial effects.

  4. Flavonoid inhibitors as novel antimycobacterial agents targeting Rv0636, a putative dehydratase enzyme involved in Mycobacterium tuberculosis fatty acid synthase II.

    Science.gov (United States)

    Brown, Alistair K; Papaemmanouil, Athina; Bhowruth, Veemal; Bhatt, Apoorva; Dover, Lynn G; Besra, Gurdyal S

    2007-10-01

    Flavonoids comprise a large group of bioactive polyphenolic plant secondary metabolites. Several of these possess potent in vivo activity against Escherichia coli and Plasmodium falciparum, targeting enzymes involved in fatty acid biosynthesis, such as enoyl-ACP-reductase, beta-ketoacyl-ACP reductase and beta-hydroxyacyl-ACP dehydratase. Herein, we report that butein, isoliquirtigenin, 2,2',4'-trihydroxychalcone and fisetin inhibit the growth of Mycobacterium bovis BCG. Furthermore, in vitro inhibition of the mycolic-acid-producing fatty acid synthase II (FAS-II) of Mycobacterium smegmatis suggests a mode of action related to those observed in E. coli and P. falciparum. Through a bioinformatic approach, we have established the product of Rv0636 as a candidate for the unknown mycobacterial dehydratase, and its overexpression in M. bovis BCG conferred resistance to growth inhibition by butein and isoliquirtigenin, and relieved inhibition of fatty acid and mycolic acid biosynthesis in vivo. Furthermore, after overexpression of Rv0636 in M. smegmatis, FAS-II was less sensitive to these inhibitors in vitro. Overall, the data suggest that these flavonoids are inhibitors of mycobacterial FAS-II and in particular Rv0636, which represents a strong candidate for the beta-hydroxyacyl-ACP dehydratase enzyme of M. tuberculosis FAS-II.

  5. Transmembrane domain II of the human bile acid transporter SLC10A2 coordinates sodium translocation.

    Science.gov (United States)

    Sabit, Hairat; Mallajosyula, Sairam S; MacKerell, Alexander D; Swaan, Peter W

    2013-11-01

    Human apical sodium-dependent bile acid transporter (hASBT, SLC10A2) is responsible for intestinal reabsorption of bile acids and plays a key role in cholesterol homeostasis. We used a targeted and systematic approach to delineate the role of highly conserved transmembrane helix 2 on the expression and function of hASBT. Cysteine mutation significantly depressed transport activity for >60% of mutants without affecting cell surface localization of the transporter. All mutants were inaccessible toward chemical modification by membrane-impermeant MTSET reagent, strongly suggesting that transmembrane 2 (TM2) plays an indirect role in bile acid substrate translocation. Both bile acid uptake and sodium dependence of TM2 mutants revealed a distinct α-helical periodicity. Kinetic studies with conservative and non-conservative mutants of sodium sensitive residues further underscored the importance of Gln(75), Phe(76), Met(79), Gly(83), Leu(86), Phe(90), and Asp(91) in hASBT function. Computational analysis indicated that Asp(91) may coordinate with sodium during the transport cycle. Combined, our data propose that a consortium of sodium-sensitive residues along with previously reported residues (Thr(134), Leu(138), and Thr(149)) from TM3 may form the sodium binding and translocation pathway. Notably, residues Gln(75), Met(79), Thr(82), and Leu(86) from TM2 are highly conserved in TM3 of a putative remote bacterial homologue (ASBTNM), suggesting a universal mechanism for the SLC10A transporter family.

  6. Critical phenomena in ethylbenzene oxidation in acetic acid solution at high cobalt(II) concentrations

    NARCIS (Netherlands)

    Gavrichkov, AA; Zakharov, [No Value

    2005-01-01

    Critical phenomena in ethylbenzene oxidation in an acetic acid solution at high cobalt(ill) concentrations (from 0.01 to 0.2 mol L-1) were studied at 60-90 degrees C by the gasometric (O-2 absorption), spectrophotometric (Co-III accumulation), and chemiluminescence (relative concentration of radical

  7. Equilibrium II: Acids and Bases. Independent Learning Project for Advanced Chemistry (ILPAC). Unit P3.

    Science.gov (United States)

    Inner London Education Authority (England).

    This unit on equilibrium is one of 10 first year units produced by the Independent Learning Project for Advanced Chemistry (ILPAC). The unit, which consists of two levels, focuses on the application of equilibrium principles to equilibria involving weak acids and bases, including buffer solutions and indicators. Level one uses Le Chatelier's…

  8. Purification and H-1 NMR spectroscopic characterization of phase II metabolites of tolfenamic acid

    DEFF Research Database (Denmark)

    Sidelmann, U. G.; Christiansen, E.; Krogh, L.;

    1997-01-01

    acid; the study shows the applicability of H-1 NMR for the identification of drug metabolites in biological fluids. In addition to NMR analysis, two metabolites were also identified by mass spectrometry (MS), The glucuronides of the following parent compounds, N-(2-methyl-3-chlorophenyl...

  9. Nature's Starships II: Simulating the Synthesis of Amino Acids in Meteorite Parent Bodies

    CERN Document Server

    Cobb, Alyssa K; Pearce, Ben K D

    2015-01-01

    Carbonaceous chondrite meteorites are known for having high water and organic material contents, including amino acids. Here we address the origin of amino acids in the warm interiors of their parent bodies (planetesimals) within a few million years of their formation, and connect this with the astrochemistry of their natal protostellar disks. We compute both the total amino acid abundance pattern as well as the relative frequencies of amino acids within the CM2 (e.g. Murchison) and CR2 chondrite subclasses based on Strecker reactions within these bodies. We match the relative frequencies to well within an order of magnitude among both CM2 and CR2 meteorites for parent body temperatures $<$ 200$^{\\circ}$C. These temperatures agree with 3D models of young planetesimal interiors. We find theoretical abundances of approximately 7x10$^5$ parts-per-billion (ppb), which is in agreement with the average observed abundance in CR2 meteorites of 4$\\pm$7x10$^5$, but an order of magnitude higher than the average obser...

  10. ESTIMATION OF PHOSPHATE ESTER HYDROLYSIS RATE CONSTANTS. II. ACID AND GENERAL BASE CATALYZED HYDROLYSIS

    Science.gov (United States)

    SPARC (SPARC Performs Automated Reasoning in Chemistry) chemical reactivity models were extended to calculate acid and neutral hydrolysis rate constants of phosphate esters in water. The rate is calculated from the energy difference between the initial and transition states of a ...

  11. Influence of the steric effect of flexible isomeric phenylenediacetic acids on the resultant lead(II) coordination polymers

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yunlong; Zhao, Yanqing; Yang, Guo-Ping, E-mail: ygp@nwu.edu.cn; Guo, Yanjun; Wang, Yao-Yu, E-mail: wyaoyu@nwu.edu.cn; Shi, Qi-Zhen

    2015-03-15

    To study the steric effect of the flexible dicarboxylate ligands on the resultant formations of coordination polymers (CPs), four new Pb{sup II} CPs [Pb(1,2-pda)(H{sub 2}O)]{sub n} (1), [Pb(1,3-pda)]{sub n}·nH{sub 2}O (2), [Pb{sub 2}(1,4-pda){sub 2}(H{sub 2}O)]{sub n}·2nH{sub 2}O (3a and 3b) have been produced by the isomeric phenylenediacetic acids (H{sub 2}pda). The X-ray crystallography study reveals that CP 1 is a two-dimensional (2D) 4-connected sql (4{sup 4}.6{sup 2}) network via the weak Pb···O interactions built on 1D chain-like structure. CP 2 crystallizes in orthorhombic system with chiral space group P2{sub 1}2{sub 1}2{sub 1}, showing a 4-connected sra (4{sup 2}.6{sup 3}.8) framework where a left-handed helical motif is formed by Pb{sup II} ions and trans-1,3-pda ligands. More interestingly, CPs 3a and 3b are two true 3D polymorphs and have the different morphology. Topologically, the framework of 3a exhibits a 4-connected lon 6{sup 6} motif, while that of 3b is a (4,6)-connected fsh (4{sup 3}.6{sup 3}){sub 2}(4{sup 6}.6{sup 6}.8{sup 3}) net. It is found that the three isomeric pda anions display the various coordination fashions in four CPs. The different structural arrangements show that the steric effect of the isomeric H{sub 2}pda tectons has a positive role in directing the final products of Pb{sup II} CPs. Also, the fluorescent properties of the CPs were studied in the solid state at room temperature. - Graphical abstract: Four new Pb{sup II}-based CPs have been produced by the isomeric phenylenediacetic acids (H{sub 2}pda). The different structural arrangements show that the steric effect of the isomeric H{sub 2}pda tectons has a positive role in directing the final products of Pb{sup II} CPs. Also, the fluorescent properties of the CPs were studied in the solid state at room temperature. - Highlights: • Four Pb{sup II}-based coordination polymers were produced by phenylenediacetic acids. • The crystal and topological structures of the

  12. Importance of ligand exchanges in Pd(II)-Brønsted acid cooperative catalytic approach to spirocyclic rings.

    Science.gov (United States)

    Jindal, Garima; Sunoj, Raghavan B

    2014-11-12

    Increasing number of reports in the most recent literature convey the use of palladium and Brønsted acids as cooperative catalytic partners. However, the mechanistic understanding of several such cooperative catalytic reactions and the origin of cooperativity continue to remain limited. In transition metal catalysis, it is typically assumed that the native ligands, such as the acetates in palladium acetate, are retained throughout the catalytic cycle. Herein, we convey the significance of invoking ligand exchanges in transition metal catalysis by using the mechanism of a representative cooperative dual-catalytic reaction. Density functional theory (M06 and B3LYP) computations have been employed to decipher the mechanism of Pd(II)-Brønsted acid catalyzed migratory ring expansion reaction of an indenyl cyclobutanol to a spirocyclic indene bearing a quaternary carbon. The molecular role of water, benzoquinone and phosphoric acid has been probed by computing the energetics using several combinations of all these as ligands on palladium. Of the two key mechanistic possibilities examined, a Wacker-type pathway (involving a semipinacol ring expansion of cyclobutanol followed by a reductive elimination) is found to be energetically more preferred over an allylic pathway wherein the ring expansion in a Pd-π-allyl intermediate occurs subsequent to the initial allylic C-H activation. The Gibbs free energies of the transition states with the native palladium acetate are much higher than a Pd-bis-phosphate species generated through ligand exchanges.

  13. Synthesis, physicochemical studies, embryos toxicity and DNA interaction of some new Iron(II) Schiff base amino acid complexes

    Science.gov (United States)

    Abdel-Rahman, Laila H.; El-Khatib, Rafat M.; Nassr, Lobna A. E.; Abu-Dief, Ahmed M.

    2013-05-01

    New Fe(II) Schiff base amino acid complexes derived from the condensation of o-hydroxynaphthaldehyde with L-alanine, L-phenylalanine, L-aspartic acid, L-histidine and L-arginine were synthesized and characterized by elemental analysis, IR, electronic spectra, and conductance measurements. The stoichiometry and the stability constants of the complexes were determined spectrophotometrically. The investigated Schiff bases exhibited tridentate coordination mode with the general formulae [Fe(HL)2]·nH2O for all amino acids except L-histidine. But in case of L-histidine, the ligand acts as tetradentate ([FeL(H2O)2]·2H2O), where HL = mono anion and L = dianion of the ligand. The structure of the prepared complexes is suggested to be octahedral. The prepared complexes were tested for their toxicity on chick embryos and found to be safe until a concentration of 100 μg/egg with full embryos formation. The interaction between CT-DNA and the investigated complexes were followed by spectrophotometry and viscosity measurements. It was found that, the prepared complexes bind to DNA via classical intercalative mode and showed a different DNA cleavage activity with the sequence: nhi > nari > nali > nasi > nphali. The thermodynamic Profile of the binding of nphali complex and CT-DNA was constructed by analyzing the experimental data of absorption titration and UV melting studies with the McGhee equation, van't Hoff's equation, and the Gibbs-Helmholtz equation.

  14. Metabolomic and mass isotopomer analysis of liver gluconeogenesis and citric acid cycle: II. Heterogeneity of metabolite labeling pattern.

    Science.gov (United States)

    Yang, Lili; Kasumov, Takhar; Kombu, Rajan S; Zhu, Shu-Han; Cendrowski, Andrea V; David, France; Anderson, Vernon E; Kelleher, Joanne K; Brunengraber, Henri

    2008-08-08

    In this second of two companion articles, we compare the mass isotopomer distribution of metabolites of liver gluconeogenesis and citric acid cycle labeled from NaH(13)CO(3) or dimethyl [1,4-(13)C(2)]succinate. The mass isotopomer distribution of intermediates reveals the reversibility of the isocitrate dehydrogenase + aconitase reactions, even in the absence of a source of alpha-ketoglutarate. In addition, in many cases, a number of labeling incompatibilities were found as follows: (i) glucose versus triose phosphates and phosphoenolpyruvate; (ii) differences in the labeling ratios C-4/C-3 of glucose versus (glyceraldehyde 3-phosphate)/(dihydroxyacetone phosphate); and (iii) labeling of citric acid cycle intermediates in tissue versus effluent perfusate. Overall, our data show that gluconeogenic and citric acid cycle intermediates cannot be considered as sets of homogeneously labeled pools. This probably results from the zonation of hepatic metabolism and, in some cases, from differences in the labeling pattern of mitochondrial versus extramitochondrial metabolites. Our data have implications for the use of labeling patterns for the calculation of metabolic rates or fractional syntheses in liver, as well as for modeling liver intermediary metabolism.

  15. Orange County Photovoltaic Project & Educational COmponent

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Renee [Orange County Government, FL (United States)

    2016-02-12

    The purpose of this report is to discuss the projects implemented, utilizing Department of Energy grant funds, to support the use and understanding of renewable energy in Orange County, Florida and the Greater Orlando Area. Orange County is located in the State of Florida and is most popularly referred to as Orlando. The greater Orlando area’s current population is 1,225,267 and in 2015 was the first destination to surpass 60 million visitors. Orange County utilized grant funds to add to the growing demand for access to charging stations by installing one level 2 dual NovaCharge CT4021 electric vehicle charging station at the Orange County/University of Florida Cooperative Extension Center. The charging station is considered a “smart” charger connected to a central network operated by a third party. Data collected includes the number of charging sessions, session start and end times, the electricity usage, greenhouse gases saved and other pertinent data used for reporting purposes. Orange County continues to support the use of electric vehicles in Metro Orlando and this project continues to bring awareness to our public regarding using alternative vehicles. Additionally, we offer all visitors to the Orange County/University of Florida Cooperative Extension Center free charges for their electric vehicles 24 hours a day. Since the operation of the charging station there have been 52 unique driver users, a total of 532.2258 kg of greenhouse gas savings and 159.03 gallons of gasoline savings. The installation of the additional electric vehicle charging station is part of a county-wide goal of promoting implementation of renewable energy technologies as well as supporting the use of electric vehicles including the Drive Electric Orlando & Florida programs. http://driveelectricorlando.com/ & ; http://www.driveelectricflorida.org/ . Grant funds were also used for Outreach and Educational efforts. Educational efforts about renewable energy were accomplished through

  16. Kinetics and Mechanism for Formation of Olefin Complexes in the Reaction between Palladium(II) and Maleic Acid.

    Science.gov (United States)

    Shi, Tiesheng; Elding, Lars I.

    1998-10-19

    Complex formation between Pd(H(2)O)(4)(2+) and maleic acid (H(2)A) has been studied at 25 degrees C and 2.00 M ionic strength in acidic aqueous solution. Reaction takes place with 1:1 stoichiometry. The kinetics has been followed by use of stopped-flow spectrophotometry under pseudo-first-order conditions with maleic acid in excess. In the concentration ranges 0.01 C where, in addition, both steps contain contributions from parallel reactions. The amplitude of the first phase increases with increasing [H(2)A](tot) and with decreasing [H(+)]. Multiwavelength global analysis of the kinetic traces and the UV-vis spectral changes suggest that a monodentate oxygen-bonded hydrogen maleate complex, [Pd(H(2)O)(3)OOCCH=CHCOOH](+), B, with stability constant K(2) = 205 +/- 40 M(-)(1) is formed as an intermediate in this first step via two parallel reversible reactions in which Pd(H(2)O)(4)(2+) reacts with maleic acid and hydrogen maleate, respectively. In the following step, B --> C, slow intramolecular ring closure with a rate constant of 0.8 +/- 0.1 s(-)(1) at 25 degrees C gives the reaction product C, which is concluded to be a 4.5-membered olefin-carboxylato chelate complex on the basis of stoichiometry and UV-vis/NMR spectra. Parallel and irreversible attack by maleic acid and hydrogen maleate acting as olefins on the intermediate B also leads to formation of C. C is stable for at least 20 h for concentrations of acid. Neither a steady-state approximation nor a rapid preequilibrium assumption can be used for the kinetics data treatment. Exact rate expressions for the fast and slow phases have been used to derive all rate constants involved. Olefins are inefficient nucleophiles toward palladium(II), even less efficient than carboxylic acids and carboxylates.

  17. Effects of background electrolytes and ionic strength on enrichment of Cd(II) ions with magnetic graphene oxide-supported sulfanilic acid.

    Science.gov (United States)

    Hu, Xin-jiang; Liu, Yun-guo; Zeng, Guang-ming; You, Shao-hong; Wang, Hui; Hu, Xi; Guo, Yi-ming; Tan, Xiao-fei; Guo, Fang-ying

    2014-12-01

    To elucidate the influence mechanisms of background electrolytes and ionic strength on Cd(II) removal, the adsorption of Cd(II) onto magnetic graphene oxide-supported sulfanilic acid (MGO-SA) in aqueous solutions containing different types and concentrations of background electrolytes was studied. The results indicate that Cd(II) adsorption was strongly dependent on pH and could be strongly affected by background electrolytes and ionic strength. The Cd(II) removal was decreased with the presence of background electrolyte cations (Na(+), K(+), Ca(2+), Mg(2+), Mn(2+), Zn(2+), and Ni(2+)), and the divalent cations exerted more obvious influences on the Cd(II) uptake than the monovalent cations at pH 6. Both Cl(-) and NO3(-) had negative effects on Cd(II) adsorption because they can form water-soluble metal-anion complexes with Cd(II) ions. The presence of 0.01molL(-1) Na3PO4 reduced the removal percentage of Cd(II) at pH5. The Cd(II) adsorption was sensitive to changes in the concentration of NaCl, NaNO3, NaClO4, and Na3PO4. Besides, the adsorption isotherm of Cd(II) onto MGO-SA could be well described by the Freundlich model and was also influenced by the type of background electrolyte ions and the ionic strength.

  18. Chromatographic analysis of the effects of fatty acids and glycation on binding by probes for Sudlow sites I and II to human serum albumin.

    Science.gov (United States)

    Anguizola, Jeanethe; Debolt, Erin; Suresh, D; Hage, David S

    2016-05-15

    The primary endogenous ligands of human serum albumin (HSA) are non-esterified fatty acids, with 0.1-2mol of fatty acids normally being bound to HSA. In type II diabetes, fatty acid levels in serum are often elevated, and the presence of high glucose results in an increase in the non-enzymatic glycation of HSA. High-performance affinity chromatography (HPAC) was used to examine the combined effects of glycation and the presence of long chain fatty acids on the binding of HSA with R-warfarin and l-tryptophan (i.e., probes for Sudlow sites I and II, the major sites for drugs on this protein). Zonal elution competition studies were used to examine the interactions of myristic acid, palmitic acid and stearic acid with these probes on HSA. It was found that all these fatty acids had direct competition with R-warfarin at Sudlow site I of normal HSA and glycated HSA, with the glycated HSA typically having stronger binding for the fatty acids at this site. At Sudlow site II, direct competition was observed for all the fatty acids with l-tryptophan when using normal HSA, while glycated HSA gave no competition or positive allosteric interactions between these fatty acids and l-tryptophan. These data indicated that glycation can alter the interactions of drugs and fatty acids at specific binding sites on HSA. The results of this study should lead to a better understanding of how these interactions may change during diabetes and demonstrate how HPAC can be used to examine drug/solute-protein interactions in complex systems.

  19. Use of coal mining waste for the removal of acidity and metal ions Al(III), Fe(III) and Mn(II) in acid mine drainage

    Energy Technology Data Exchange (ETDEWEB)

    Geremias, R.; Laus, R.; Macan, J.M.; Pedrosa, R.C.; Laranjeira, M.C.M.; Silvan, J.; Favere, F.V. [Universidade Federal de Santa Catarina, Florianopolis (Brazil)

    2008-08-15

    The coal industry may generate acid mine drainage (AMD) and mining wastes, which may adversely affect the quality of the environment. In this study we propose the use of this waste in the removal of acidity and metal ions, as well as in the reduction of the toxicity of AMD. A physico-chemical analysis of the waste shows the presence of mainly SiO{sub 2}, Al{sub 2}O{sub 3} and Fe{sub 2}O{sub 3} and a superficial area of 4.316 m{sup 2} g{sup -1}. The treatment of AMD with the waste resulted in an increase in pH from 2.6 to 7.8 and removed 100% of the Al(III), 100% of the Fe(III) and 89% of the Mn (II). We also observed that the high toxicity of the AMD towards Daphnia magna (LC50 = 3.68%) and Artemia sp. (LC50 = 4.97%) was completely eliminated after treatment with the waste. The data obtained allow us to propose that the waste can be used in the treatment of AMD, providing an economic use for the waste.

  20. Poly(γ-glutamic acid) and poly(γ-glutamic acid)-based nanocomplexes enhance type II collagen production in intervertebral disc.

    Science.gov (United States)

    Antunes, Joana C; Pereira, Catarina Leite; Teixeira, Graciosa Q; Silva, Ricardo V; Caldeira, Joana; Grad, Sibylle; Gonçalves, Raquel M; Barbosa, Mário A

    2017-01-01

    Intervertebral disc (IVD) degeneration often leads to low back pain, which is one of the major causes of disability worldwide, affecting more than 80% of the population. Although available treatments for degenerated IVD decrease symptoms' progression, they fail to address the underlying causes and to restore native IVD properties. Poly(γ-glutamic acid) (γ-PGA) has recently been shown to support the production of chondrogenic matrix by mesenchymal stem/stromal cells. γ-PGA/chitosan (Ch) nanocomplexes (NCs) have been proposed for several biomedical applications, showing advantages compared with either polymer alone. Hence, this study explores the potential of γ-PGA and γ-PGA/Ch NCs for IVD regeneration. Nucleotomised bovine IVDs were cultured ex vivo upon injection of γ-PGA (pH 7.4) and γ-PGA/Ch NCs (pH 5.0 and pH 7.4). Tissue metabolic activity and nucleus pulposus DNA content were significantly reduced when NCs were injected in acidic-buffered solution (pH 5.0). However, at pH 7.4, both γ-PGA and NCs promoted sulphated glycosaminoglycan production and significant type II collagen synthesis, as determined at the protein level. This study is a first proof of concept that γ-PGA and γ-PGA/Ch NCs promote recovery of IVD native matrix, opening new perspectives on the development of alternative therapeutic approaches for IVD degeneration.

  1. Photodissociation of organic molecules in star-forming regions II: Acetic acid

    CERN Document Server

    Pilling, S; Boechat-Roberty, H M

    2006-01-01

    Fragments from organic molecule dissociation (such as reactive ions and radicals) can form interstellar complex molecules like amino acids. The goal of this work is to experimentally study photoionization and photodissociation processes of acetic acid (CH$_3$COOH), a glycine (NH$_2$CH$_2$COOH) precursor molecule, by soft X-ray photons. The measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS), employing soft X-ray photons from a toroidal grating monochromator (TGM) beamline (100 - 310 eV). Mass spectra were obtained using the photoelectron photoion coincidence (PEPICO) method. Kinetic energy distribution and abundances for each ionic fragment have been obtained from the analysis of the corresponding peak shapes in the mass spectra. Absolute photoionization and photodissociation cross sections were also determined. We have found, among the channels leading to ionization, that only 4-6% of CH$_3$COOH survive the strong ionization field. CH$_3$CO$^+$, COOH$^+$ and CH$_3^+$ ions are the mai...

  2. Phenolation of ±catechin with mineral acids. II. Identification of new reaction products

    Science.gov (United States)

    Weiling Peng; Anthony H. Conner; Richard W. Hemingway

    1997-01-01

    To investigate the reactions that occur in the flavanoid unit during the liquefaction of tannin in phenol, the phenolysis of ±catechin was studied using either H2SO4, HCl, or BF3 2H2O as acid catalyst. In addition to 2-[3-(3,4-dihydroxyphenyl)-2-hydroxy-3-(4-hydroxyphenyl)propyl]-1,3,5-benzenetriol (1) and 2-[(3,4-dihydroxyphenyl)(4-hydroxyphenyl)methyl]-2,3-dihydro-4,...

  3. Trichloroacetic acid in Norway spruce/soil-system. II. Distribution and degradation in the plant.

    Science.gov (United States)

    Forczek, S T; Uhlírová, H; Gryndler, M; Albrechtová, J; Fuksová, K; Vágner, M; Schröder, P; Matucha, M

    2004-07-01

    Independently from its origin, trichloroacetic acid (TCA) as a phytotoxic substance affects coniferous trees. Its uptake, distribution and degradation were thus investigated in the Norway spruce/soil-system using 14C labeling. TCA is distributed in the tree mainly by the transpiration stream. As in soil, TCA seems to be degraded microbially, presumably by phyllosphere microorganisms in spruce needles. Indication of TCA biodegradation in trees is shown using both antibiotics and axenic plants.

  4. Haemoglobins of the shark, Heterodontus portusjacksoni II. Amino acid sequence of the alpha-chain.

    Science.gov (United States)

    Nash, A R; Fisher, W K; Thompson, E O

    1976-03-01

    The amino acid sequence of the alpha-chain of the principal haemoglobin from the shark, H. portusjacksoni has been determined. The chain has 148 residues and is acetylated at the amino terminal. The soluble peptides obtained by tryptic and chymotryptic digestion of the protein or its cyanogen bromide fragments were isolated by gel filtration, paper ionophoresis and paper chromatography. The amino acid sequences were determined by the dansyl-Edman procedure. The insoluble "core" peptide from the tryptic digestion contained 34 residues and required cleavage by several prosteases before the sequence was established. Compared with human alpha-chain there are 88 amino acid differences including the additional seven residues which appear on the amino terminal of the shark chain. There is also one deletion and one insertion. The chain contains no tryptophan but has four cysteinyl residues which is the highest number of such residues recorded for a vertebrate globin. In the alpha1beta1 contact sites there are four changes in the oxyhaemoglobin form and six deoxy form. Nine of the 16, alpha1beta1 contact sites show variation while three of the haem contact sites have changed in comparison to the residues known to be involved in these interactions in horse haemoglobin alpha-chain. Use of the sequence data to estimate a time of divergence of the shark from the main vertebrate line yielded the value of 410 +/- 46 million years. The data, in general, support the palaeontological view that bony fishes arose before the elasmobranchs.

  5. Thermodynamics of mixed-ligand complex formation of mercury (II) ethylenediaminetetraacetate with amino acids in solution

    Energy Technology Data Exchange (ETDEWEB)

    Pyreu, Dmitrii, E-mail: pyreu@mail.ru [Department of Inorganic and Analytic Chemistry, Ivanovo State University, Ermak 39, Ivanovo 153025 (Russian Federation); Kozlovskii, Eugenii [Department of Inorganic and Analytic Chemistry, Ivanovo State University, Ermak 39, Ivanovo 153025 (Russian Federation); Gruzdev, Matvei; Kumeev, Roman [Institute of Solution Chemistry, Ivanovo (Russian Federation)

    2012-11-20

    Highlights: Black-Right-Pointing-Pointer Stable mixed ligand complexes of HgEdta with amino acids at physiological pH value. Black-Right-Pointing-Pointer The thermodynamic and NMR data evident the ambidentate coordination mode of arginine. Black-Right-Pointing-Pointer Participation of the guanidinic group of Arg in coordination process. Black-Right-Pointing-Pointer Binuclear complexes (HgEdta){sub 2}L with the bridging function of amino acid. - Abstract: The mixed-ligand complex formation in the systems Hg{sup 2+} - Edta{sup 4-} - L{sup -}(L = Arg, Orn, Ser) has been studied by means of calorimetry, pH-potentiometry and NMR spectroscopy in aqueous solution at 298.15 K and the ionic strength of I = 0.5 (KNO{sub 3}). The thermodynamic parameters of formation of the HgEdtaL, HgEdtaHL and (HgEdta){sub 2}L complexes have been determined. The most probable coordination mode for the complexone and the amino acid in the mixed-ligand complexes was discussed.

  6. Photodissociation of organic molecules in star-forming regions. II. Acetic acid

    Science.gov (United States)

    Pilling, S.; Santos, A. C. F.; Boechat-Roberty, H. M.

    2006-04-01

    Fragments from organic molecule dissociation (such as reactive ions and radicals) can form interstellar complex molecules like amino acids. The goal of this work is to experimentally study photoionization and photodissociation processes of acetic acid (CH3COOH), a glycine (NH2CH2COOH) precursor molecule, by soft X-ray photons. The measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS), employing soft X-ray photons from a toroidal grating monochromator (TGM) beamline (100-310 eV). Mass spectra were obtained using the photoelectron photoion coincidence (PEPICO) method. Kinetic energy distribution and abundances for each ionic fragment have been obtained from the analysis of the corresponding peak shapes in the mass spectra. Absolute photoionization and photodissociation cross sections were also determined. We have found, among the channels leading to ionization, that only 4-6% of CH3COOH survive the strong ionization field. CH3CO^+, COOH+ and CH3+ ions are the main fragments, and the presence of the former may indicate that the production-destruction process of acetic acid in hot molecular cores (HMCs) could decrease the H2O abundance since the net result of this process converts H2O into OH + H^+. The COOH+ ion plays an important role in ion-molecule reactions to form large biomolecules like glycine.

  7. Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases. Part 3: Michael addition reactions and miscellaneous transformations.

    Science.gov (United States)

    Aceña, José Luis; Sorochinsky, Alexander E; Soloshonok, Vadim

    2014-09-01

    The major goal of this review is a critical discussion of the literature data on asymmetric synthesis of α-amino acids via Michael addition reactions involving Ni(II)-complexes of amino acids. The material covered is divided into two conceptually different groups dealing with applications of: (a) Ni(II)-complexes of glycine as C-nucleophiles and (b) Ni(II)-complexes of dehydroalanine as Michael acceptors. The first group is significantly larger and consequently subdivided into four chapters based on the source of stereocontrolling element. Thus, a chiral auxiliary can be used as a part of nucleophilic glycine Ni(II) complex, Michael acceptor or both, leading to the conditions of matching vs. mismatching stereochemical preferences. The particular focus of the review is made on the practical aspects of the methodology under discussion and mechanistic considerations.

  8. Citric Acid-Assisted Hydrothermal Synthesis of Bi2WO6 Nanosheets for Highly Efficient Degradation of Methyl Orange under Visible Light Irradiation%柠檬酸辅助水热法制备可见光高效去除甲基橙的Bi2WO6纳米片

    Institute of Scientific and Technical Information of China (English)

    陈渊; 刘国聪; 李志友; 黄苏萍; 周科朝

    2011-01-01

    Bi2WO6 nanosheets with highly efficient photocatalytic activity under visible light irradiation were prepared by a hydrothermal method using Bi(NO3)3·5H2O and Na2WO3·2H2O as starting materials and citric acid as the chelating agent. The properties of the as-prepared samples were investigated by X-ray diffraction, field emission high resolution transmission electron microscopy, Raman spec-troscopy, and UV-Vis diffusion reflectance spectroscopy. The photocatalytic properties of the Bi2WO6 catalyst were also investigated. The results show that Bi2WO6 nanosheets with orthorhombic structure can be obtained by adjusting the pH value of the reaction system. Compared with the Bi2WO6 catalyst prepared without citric acid, the Raman bands of the nanosheets assisted with citric acid present blue shift and show a significant red shift in the absorption band and its band gap was narrowed to 2.55 eV. The pH value of the reaction system is the main factor affecting the visible light-driven photocatalytic activity. The Bi2WO6 sample prepared at pH = 7.0 shows a higher photocatalytic activity. Over this catalyst, the 100% degradation of methyl orange solution (10 mg/L) is obtained after visible light irradiation for 15 min. In addition, after 5 recycles, there is no significant decrease in its photocatalytic activity, indicating that Bi2WO6 is a stable photocatalyst for degradation of methyl orange under visible light irradiation.%以Bi(NO3)3·5H2O和Na2WO3 ·2H2O为原料,以柠檬酸为络合剂,采用辅助水热法制备了Bi2WO6纳米片,运用X射线衍射、扫描电镜、场发射高分辨透射电镜、拉曼光谱、红外光谱和紫外-可见漫反射光谱等手段对样品进行了表征,并考察了该催化剂光催化去除甲基橙反应性能.结果表明,通过调节体系的pH值可制得结晶度良好的正交晶系钨铋矿型结构的Bi2WO6纳米片状晶体.柠檬酸的添加使得制备的Bi2WO6颗粒的拉曼光谱特征峰发生蓝移,紫外-可见

  9. MATHEMATICAL MODELING OF ORANGE SEED DRYING KINETICS

    Directory of Open Access Journals (Sweden)

    Daniele Penteado Rosa

    2015-06-01

    Full Text Available Drying of orange seeds representing waste products from juice processing was studied in the temperatures of 40, 50, 60 and 70 °C and drying velocities of 0.6, 1.0 and 1.4 m/s. Experimental drying kinetics of orange seeds were obtained using a convective air forced dryer. Three thin-layer models: Page model, Lewis model, and the Henderson-Pabis model and the diffusive model were used to predict the drying curves. The Henderson-Pabis and the diffusive models show the best fitting performance and statistical evaluations. Moreover, the temperature dependence on the effective diffusivity followed an Arrhenius relationship, and the activation energies ranging from 16.174 to 16.842 kJ/mol

  10. Flora of the Orange Cliffs of Utah

    Energy Technology Data Exchange (ETDEWEB)

    Shultz, L.M.; Neely, E.E.; Tuhy, J.S.

    1987-04-30

    The Orange Cliffs area, an area rich in oil sands deposits and defined here as part of the Colorado Plateau floristic province, harbors approximately 209 species in 123 genera and 49 families. Because of the potential of exploitation of the oil sands deposits in the area, a species checklist was made and a discussion of physical and floristic aspects of the region is given here. The flora is compared statistically to the San Rafael Swell flora, which is also a subset of the Colorado Plateau. They define six vegetation types and three edaphic communities; these are described and mapped. Of eleven endemic plant species in the Orange Cliffs, three are local and rare. Sites for Astragalus nidularius, A. moencoppensis, and Xylorhiza glabriuscula var. linearifolia are discussed and mapped. 24 references, 3 figures, 3 tables.

  11. The novel kinetics expression of Cadmium (II) removal using green adsorbent horse dung humic acid (Hd-Ha)

    Science.gov (United States)

    Basuki, Rahmat; Santosa, Sri Juari; Rusdiarso, Bambang

    2017-03-01

    Humic acid from dry horse dung powder has been prepared and this horse dung humic acid (HD-HA) was then applied as a sorbent to adsorb Cadmium(II) from a solution. Characterization of HD-HA was conducted by detection of its functional group, UV-Vis spectra, ash level, and total acidity. Result of the work showed that HD-HA had similar character compared with peat soil humic acid (PS-HA) and previous researchers. The adsorption study of this work was investigated by batch experiment in pH 5. The thermodynamics parameters in this work were determined by the Langmuir isotherm model for monolayer sorption and Freundlich isotherm model multilayer sorption. Monolayer sorption capacity (b) for HD-HA was 1.329 × 10-3 mol g-1, equilibrium constant (K) was 5.651 (mol/L)-1, and multilayer sorption capacity was 2.646 × 10-2 mol g-1. The kinetics parameters investigated in this work were determined by the novel kinetics expression resulted from the mathematical derivation the availability of binding sites of sorbent. Adsorption rate constant (ka) from this novel expression was 43.178 min-1 (mol/L)-1 and desorption rate constant (kd) was 1.250 × 10-2 min-1. Application of the kinetics model on sorption Cd(II) onto HD-HA showed the nearly all of models gave a good linearity. However, only this proposed kinetics expression has good relation with Langmuir model. The novel kinetics expression proposed in this paper seems to be more realistic and reasonable and close to the experimental real condition because the value of ka/kd (3452 (mol/L)-1) was fairly close with K from Langmuir isotherm model (5651 (mol/L)-1). Comparison of this novel kinetics expression with well-known Lagergren pseudo-first order kinetics and Ho pseudo-second order kinetics was also critically discussed in this paper.

  12. Call cultures in orang-utans?

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    Serge A Wich

    Full Text Available BACKGROUND: Several studies suggested great ape cultures, arguing that human cumulative culture presumably evolved from such a foundation. These focused on conspicuous behaviours, and showed rich geographic variation, which could not be attributed to known ecological or genetic differences. Although geographic variation within call types (accents has previously been reported for orang-utans and other primate species, we examine geographic variation in the presence/absence of discrete call types (dialects. Because orang-utans have been shown to have geographic variation that is not completely explicable by genetic or ecological factors we hypothesized that this will be similar in the call domain and predict that discrete call type variation between populations will be found. METHODOLOGY/PRINCIPAL FINDINGS: We examined long-term behavioural data from five orang-utan populations and collected fecal samples for genetic analyses. We show that there is geographic variation in the presence of discrete types of calls. In exactly the same behavioural context (nest building and infant retrieval, individuals in different wild populations customarily emit either qualitatively different calls or calls in some but not in others. By comparing patterns in call-type and genetic similarity, we suggest that the observed variation is not likely to be explained by genetic or ecological differences. CONCLUSION/SIGNIFICANCE: These results are consistent with the potential presence of 'call cultures' and suggest that wild orang-utans possess the ability to invent arbitrary calls, which spread through social learning. These findings differ substantially from those that have been reported for primates before. First, the results reported here are on dialect and not on accent. Second, this study presents cases of production learning whereas most primate studies on vocal learning were cases of contextual learning. We conclude with speculating on how these findings might

  13. Synthesis, Crystal Structure, and Luminescence Properties of a New Calcium(II Coordination Polymer Based on L-Malic Acid

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    Duraisamy Senthil Raja

    2013-01-01

    Full Text Available A new calcium coordination polymer [Ca(HL-MA]n (H3L-MA = L-malic acid has been solvothermally synthesized. The structure of the newly synthesized complex has been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, reflectance UV-Vis & IR spectra, powder X-ray diffraction (PXRD, and thermogravimetric analysis (TGA. The single crystal structure analysis showed that the complex forms three-dimensional framework. The new Ca(II complex has displayed very high thermal stability which was inferred from TGA and PXRD results. As far as the optical property of the new complex is concerned, the complex emitted its own characteristic sensitized luminescence.

  14. Mono and binuclear ruthenium(II) complexes containing 5-chlorothiophene-2-carboxylic acid ligands: Spectroscopic analysis and computational studies

    Science.gov (United States)

    Swarnalatha, Kalaiyar; Kamalesu, Subramaniam; Subramanian, Ramasamy

    2016-11-01

    New Ruthenium complexes I, II and III were synthesized using 5-chlorothiophene-2-carboxylic acid (5TPC), as ligand and the complexes were characterized by elemental analysis, FT-IR, 1H, 13C NMR, and mass spectroscopic techniques. Photophysical and electrochemical studies were carried out and the structures of the synthesized complex were optimized using density functional theory (DFT). The molecular geometry, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energies and Mulliken atomic charges of the molecules are determined at the B3LYP method and standard 6-311++G (d,p) basis set starting from optimized geometry. They possess excellent stabilities and their thermal decomposition temperatures are 185 °C, 180 °C and 200 °C respectively, indicating that the metal complexes are suitable for the fabrication processes of optoelectronic devices.

  15. Palladium(II-catalyzed Heck reaction of aryl halides and arylboronic acids with olefins under mild conditions

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    Tanveer Mahamadali Shaikh

    2013-08-01

    Full Text Available A series of general and selective Pd(II-catalyzed Heck reactions were investigated under mild reaction conditions. The first protocol has been developed employing an imidazole-based secondary phosphine oxide (SPO ligated palladium complex (6 as a precatalyst. The catalytic coupling of aryl halides and olefins led to the formation of the corresponding coupled products in excellent yields. A variety of substrates, both electron-rich and electron-poor olefins, were converted smoothly to the targeted products in high yields. Compared with the existing approaches employing SPO–Pd complexes in a Heck reaction, the current strategy features mild reaction conditions and broad substrate scope. Furthermore, we described the coupling of arylboronic acids with olefins, which were catalyzed by Pd(OAc2 and employed N-bromosuccinimide as an additive under ambient conditions. The resulted biaryls have been obtained in moderate to good yields.

  16. Copper(II) complexes of bis(amino amide) ligands: effect of changes in the amino acid residue.

    Science.gov (United States)

    Martí, Inés; Ferrer, Armando; Escorihuela, Jorge; Burguete, M Isabel; Luis, Santiago V

    2012-06-14

    A family of ligands derived from bis(amino amides) containing aliphatic spacers has been prepared, and their protonation and stability constants for the formation of Cu(2+) complexes have been determined potentiometrically. Important differences are associated to both the length of the aliphatic spacer and the nature of the side chains derived from the amino acid. In general, ligands containing aliphatic side chains display higher basicities as well as stability constants with Cu(2+). In the same way, basicities and stability constants tend to increase when decreasing the steric hindrance caused by the corresponding side-chain. FT-IR, UV-vis and ESI-MS were used for analyzing the complex species detected in the speciation diagram. UV-vis studies showed the presence of different coordination environments for the copper(II) complexes. Complexes with different stoichiometries can be formed in some instances. This was clearly highlighted with the help of ESI-MS experiments.

  17. A Hexasaccharide Containing Rare 2‐O‐Sulfate‐Glucuronic Acid Residues Selectively Activates Heparin Cofactor II

    Science.gov (United States)

    Sankarayanarayanan, Nehru Viji; Strebel, Tamara R.; Boothello, Rio S.; Sheerin, Kevin; Raghuraman, Arjun; Sallas, Florence; Mosier, Philip D.; Watermeyer, Nicholas D.

    2017-01-01

    Abstract Glycosaminoglycan (GAG) sequences that selectively target heparin cofactor II (HCII), a key serpin present in human plasma, remain unknown. Using a computational strategy on a library of 46 656 heparan sulfate hexasaccharides we identified a rare sequence consisting of consecutive glucuronic acid 2‐O‐sulfate residues as selectively targeting HCII. This and four other unique hexasaccharides were chemically synthesized. The designed sequence was found to activate HCII ca. 250‐fold, while leaving aside antithrombin, a closely related serpin, essentially unactivated. This group of rare designed hexasaccharides will help understand HCII function. More importantly, our results show for the first time that rigorous use of computational techniques can lead to discovery of unique GAG sequences that can selectively target GAG‐binding protein(s), which may lead to chemical biology or drug discovery tools. PMID:28124818

  18. In silico prediction of drug dissolution and absorption with variation in intestinal pH for BCS class II weak acid drugs: ibuprofen and ketoprofen.

    Science.gov (United States)

    Tsume, Yasuhiro; Langguth, Peter; Garcia-Arieta, Alfredo; Amidon, Gordon L

    2012-10-01

    The FDA Biopharmaceutical Classification System guidance allows waivers for in vivo bioavailability and bioequivalence studies for immediate-release solid oral dosage forms only for BCS class I. Extensions of the in vivo biowaiver for a number of drugs in BCS class III and BCS class II have been proposed, in particular, BCS class II weak acids. However, a discrepancy between the in vivo BE results and in vitro dissolution results for BCS class II acids was recently observed. The objectives of this study were to determine the oral absorption of BCS class II weak acids via simulation software and to determine if the in vitro dissolution test with various dissolution media could be sufficient for in vitro bioequivalence studies of ibuprofen and ketoprofen as models of carboxylic acid drugs. The oral absorption of these BCS class II acids from the gastrointestinal tract was predicted by GastroPlus™. Ibuprofen did not satisfy the bioequivalence criteria at lower settings of intestinal pH of 6.0. Further the experimental dissolution of ibuprofen tablets in a low concentration phosphate buffer at pH 6.0 (the average buffer capacity 2.2 mmol l (-1) /pH) was dramatically reduced compared with the dissolution in SIF (the average buffer capacity 12.6 mmol l (-1) /pH). Thus these predictions for the oral absorption of BCS class II acids indicate that the absorption patterns depend largely on the intestinal pH and buffer strength and must be considered carefully for a bioequivalence test. Simulation software may be a very useful tool to aid the selection of dissolution media that may be useful in setting an in vitro bioequivalence dissolution standard.

  19. Simultaneous and sensitive analysis of aliphatic carboxylic acids by ion-chromatography using on-line complexation with copper(II) ion.

    Science.gov (United States)

    Kemmei, Tomoko; Kodama, Shuji; Yamamoto, Atsushi; Inoue, Yoshinori; Hayakawa, Kazuichi

    2015-01-02

    A new approach to ion chromatography is proposed to improve the UV detection of aliphatic carboxylic acids separated by anion-exchange chromatography. When copper(II) ion added to the mobile phase, it forms complexes with carboxylic acids that can be detected at 240 nm. The absorbance was found to increase with increasing copper(II) ion concentration. The retention times of α-hydroxy acids were also found to depend on the copper(II) ion concentration. Addition of acetonitrile to the mobile phase improved the separation of aliphatic carboxylic acids. The detection limits of the examined carboxylic acids (formate, glycolate, acetate, lactate, propionate, 3-hydroxypropionate, n-butyrate, isobutyrate, n-valerate, isovalerate, n-caproate) calculated at S/N=3 ranged from 0.06 to 3 μM. The detector signal was linear over three orders of magnitude of carboxylic acid concentration. The proposed method was successfully applied to analyze aliphatic carboxylic acids in rainwater and bread.

  20. Postharvest response of oranges of ethylene

    Energy Technology Data Exchange (ETDEWEB)

    Aharoni, Y.; Lattar, F.S.; Monselise, S.P.

    1969-01-01

    Since the effect of ethylene on the respiration rate of young unripe oranges has not yet been described, experiments were carried out to study the respiratory response of such fruits to ethylene. Oranges (Citrus sinensis (L.) Osbeck) of the Washington navel, Shamouti and Valencia varieties, growing on a sandy loam near Rehovot, Israel, were picked in June, July, September, December and January. Immediately after picking, they were weighed, placed in glass jars, and stored at 20/sup 0/. Each experiment comprised 12 jars, 4 for each variety. A constant stream (200 ml/min) of air containing 20 ppm of ethylene was run through the jars. The respiration rate was measured by the amount of CO/sub 2/ evolved by the fruits, and based on a fresh weight unit. The results show that in all 3 varieties, ethylene caused an immediate rise in respiration rate, at all stages of development tested, regardless of whether it was applied from the beginning of the test or after a certain period of storage in air. The pattern of response to ethylene of young unripe oranges (picked in June, July, and September) was therefore similar to that of ripe ones (picked in December and January).