• Title/Summary/Keyword: Oxygen addition

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Flavonoid Components in Plants of the Genus Scutellaria

  • YunChoi, Hye-Sook
    • Korean Journal of Pharmacognosy
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    • v.23 no.4
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    • pp.201-210
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    • 1992
  • Scutellariae plants contain a large number of flavonoids and in addition, many of them are with unusual A- and/or B-ring substitutions. The total number of flavonoids reported up to the middle of 1991 are 137 including 89 of flavones, flavonols and their glycosides including 3 C-glycosides$(1{\sim}89)$, 39 of flavanones, dihydroflavonols and their glycosides $(90{\sim}128)$, 8 of chalcones $(129{\sim}136)$ and one biflavonoid, 8, 8'-bibaicalein(137). More than half of the flavonoids are with either unusual 5-metboxy(2'-methoxy in case of chalcones) in A-ring and/or 2'-oxygenation(2-oxygenation in case of chalcones) in B-ring substitutions. Four flavones, four flavanones and two chalcones are with methylation at 5-OH(2'-OH in case of chalcones) and six of them also have 2'-oxygenations(2- in case of chalcones). Sixtyeight out of total 137 flavonoids have oxygenated substitution at 2'-(2- in case of chalcones) position of B-ring and in addition, 27 of them have another oxygen function at 6'-(6- in case of chalcones) and 18 of them have additional oxygen substitutions either at 3'-, 5'-,3',6'-or 3', 4', 5'-(3, 4, 5- in case of chalcones) positions. The distribution and isolation of flavonoid components of Scutellariae plants are tabulated with references.

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Sorption and Degradation of Benzene by Hydrogen Peroxide and Microorganism in a Sandy Soil (사질토양에서의 과산화수소 및 미생물에 의한 Benzene의 흡착 및 분해)

  • 백두성;박춘화;김동주
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2000.05a
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    • pp.101-107
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    • 2000
  • Column tests using KCl and Benzene as tracers were conducted for four different cases: 1) no hydrogen peroxide and no microorganism; 2) hydrogen peroxide only; 3) microorganism only; 4) hydrogen and microorganism to investigate the sorption and degradation characteristics of Benzene. The observed BTCs of KCl and Benzene in all cases showed that the arrival times of the peaks of both tracers coincided well but the peak concentration of Benzene was much lower than that of KCl. This result reveals that a predominant process affecting the transport of Benzene in a sandy soil is an irreversible sorption and/or degradation rather than retardation. Decay of Benzene through sorption and degradation increased with the addition of hydrogen peroxide and/or microorganism. Dissolved oxygen decreased with the increase of Benzene in all cases indicating that Benzene was degraded by dissolved oxygen. For BTCs with the addition of microorganisms (case 3 and case 4), microorganism showed much lower concentrations compared to the initial levels and an increasing tendency with time although concentrations of Benzene returned to zero, indicating a possible retardation of microorganism due to reversible and irreversible sorption to the particle surfaces.

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Non-chlorine Bleaching of Oak Kraft Pulp by Ozone (오존을 이용한 신갈나무 크라프트펄프의 무염소표백)

  • 김동호;백기현
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.29 no.2
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    • pp.36-45
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    • 1997
  • Newly bleaching sequence using oxygen, ozone and hydrogen peroxide has introduced to avoid pollution hazards from chlorinated organic compounds, because chlorine dioxide substitution bleaching was produced a little chlorinated organic substance. Oxygen-type chemicals replaced for chlorine has attracted much research attention. Bleachability of ozone was improved at low temperature and high pulp consistency. In third bleaching followed OZ bleaching, addition of O2 and NaBH4 in alkali extraction was effective than only alkali extraction. Bleachability of pulps in ozone bleaching(Z) was improved at higher consistency and lower temperature The addition O2 and NaBH4 in alkali extraction after OZ bleaching sequence improved brightness, when compared to those obtained by only alkaline extraction. Pulps bleached by ECF bleaching sequences such as OZEoD and OZEopD was obtained by 90% ISO brightness. The brightness of pulp bleached by TCF sequences with the ozone dosage of 1.6% was approached to target brightness (88~90%ISO). Pulps bleached Z stage combined bleaching sequence was reduced the viscosity to a little greater extent. However, physical properties of pulps was not great different compared to those bleached by conventional bleaching sequences. A pollution index of bleaching effluente by ozone combined bleaching sequences was lower than by conventional bleaching sequence, but somewhat higher than multistage bleaching sequences combined C/D stage.

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Characteristics of Hydrogen Production from Methanol and Ethanol Using Plasma Reactor and Ozone Decomposition Catalyst (플라즈마 리액터 및 오존분해 촉매를 이용한 메탄올 및 에탄올로부터 수소발생특성)

  • Koo, Bon-Kook;Kim, Yong-Chun;Jang, Mun-Gug;Kim, Jong-Hyun;Park, Jae-Youn;Han, Sang-Bo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.10
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    • pp.116-124
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    • 2011
  • In this work, the effect of the initial concentration of methanol and ethanol, and the addition of oxygen molecules were discussed to improve the hydrogen generation using non-thermal plasma reactor effectively. In addition, the effect of ozone decomposition catalyst of manganese dioxide and its quantity was investigated. First, hydrogen concentration increased until an initial concentration of about 40,000[ppm] of methanol and thereafter it was saturated. Henceforth, hydrogen concentration decreased with increasing the oxygen percent on the carrier gas of nitrogen about both substances. Related with the effect of catalyst, it increased upto 60[g], but it was not changed largely after that. Consequently, it is confirmed that the hybrid process using plasma process and catalytic surface chemical reaction is a very promising way to increase the efficiency of hydrogen generation as investigated in this work.

Effect of Copper ion on Xanthine Oxidase Activity and Type Conversion (Xanthine oxidase 활성 및 형전환에 미치는 구리이온의 영향)

  • Huh, Keun;Lee, Sang-Il;Park, Jeen-Woo
    • YAKHAK HOEJI
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    • v.38 no.2
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    • pp.211-217
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    • 1994
  • Copper intoxication and disturbance of copper metabolism induced various oxygen-derived free radicals related damages. The effect of copper ion on xanthine oxidase activity and type conversion of the enzyme which is concerned to generation of reactive oxygen species, was investigated, It was observed that xanthine oxidase activity was increased by addition of copper ion in the reaction mixture in proportional to the concentration of the metal ion until $60\;{\mu}M$, while the enzyme activity was inhibited in higher concentration of copper treatment. On the other hand, xanthine dehydrogenase activity was inhibited by copper ion addition with concentration dependently. Preincubation of enzyme source with $30\;{\mu}M$ of copper ion, which concentration marked increased the xanthine oxidase activity, unchanged the enzyme activity and type conversion compare to control in vitro system. It was also observed that copper induced xanthine oxidase activity and the enzyme type conversion was protected by dithiothreitol and penicillamine. These results indicate that the increment of the type conversion of xanthine oxidase necessarilly need the presence of copper ion in enzyme assay system.

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OUT-OF-PILE MECHANICAL PERFORMANCE AND MICROSTRUCTURE OF RECRYSTALLIZED ZR-1.5 NB-O-S ALLOYS

  • Ko, S.;Lee, J.M.;Hong, S.I.
    • Nuclear Engineering and Technology
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    • v.43 no.5
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    • pp.421-428
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    • 2011
  • The out-of-pile mechanical performance and microstructure of recrystallized Zr-1.5 Nb-S alloy was investigated. The strength of the recrystallized Zr-1.5Nb-O-S alloys was observed to increase with the addition of sulfur over a wide temperature range, from room temperature up to $300^{\circ}C$. A yield drop and stress serrations due to dynamic strain were observed at room temperature and $300^{\circ}C$. Wavy and curved dislocations and loosely knit tangles were observed after strained to 0.07 at room temperature, suggesting that cross slip is easier. At $300^{\circ}C$, however, dislocations were observed to be straight and aligned along the slip plane, suggesting that cross slip is rather difficult. At $300^{\circ}C$, oxygen atoms are likely to exert a drag force on moving dislocations, intensifying the dynamic strain aging effect. Oxygen atoms segregated at partial dislocations of a screw dislocation with the edge component may hinder the cross slip, resulting in the rather straight dislocations distributed on the major slip planes. Recrystallized Zr-Nb-S alloys exhibited ductile fracture surfaces, supporting the beneficial effect of sulfur in zirconium alloys. Oxidation resistance in air was also found to be improved with the addition of sulfur in Zr-1.5 Nb-O alloys.

Saccharomyces cerevisiae에서 myo-Inositol 결핍에 의한 Respiratory capacity의 감소

  • 정경환;이준식
    • Microbiology and Biotechnology Letters
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    • v.24 no.4
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    • pp.485-492
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    • 1996
  • myo-Inositol, a growth factor for Saccharomyces cerevisiae (S. cerevisiae), has been known to be incorporated into phosphatidylinositol (PI), which is a kind of phospholipid in the cell membrane, by a membrane-associated PI-synthesizing enzyme. The deficiency of myo-inositol in S. cerevisiae adversely affected the membrane structure and function. On the basis of biochemical functions of myo-inositol, the effect of deficiency of myo-inositol on the aerobic glucose metabolism was investigated by measuring specific oxygen uptake rate (Q$_{O2}$) used as an indicator representing the respiratory capacity of S. cerevisiae in batch and continuous cultures. The respiratory capacity of aerobic glucose metabolism in S. cerevisiae was also monitored after glucose pulse-addition in a continuous culture (D=0.2, 1/hr), in which glucose was utilized through respiratory metabolism. The deficiency of myo-inositol was found to lead to both the decrease of the maximum specific oxygen uptake rate (Q$_{O2max}$) observed from the batch as well as in the continuous culture experiment and the decrease of the respiratory capacity of aerobic glucose metabolism of S. cerevisiae determined from the glucose pulse-addition experiment, in which the glucose flux into respiratory and fermen- tative metabolism was quantitatively analyzed.

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A New-Generation Fluorescent-Based Metal Sensor - iLOV Protein

  • Ravikumar, Yuvaraj;Nadarajan, Saravanan Prabhu;Lee, Chong-Soon;Rhee, Jin-Kyu;Yun, Hyungdon
    • Journal of Microbiology and Biotechnology
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    • v.25 no.4
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    • pp.503-510
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    • 2015
  • The iLOV protein belongs to a family of blue-light photoreceptor proteins containing a light-oxygen-voltage sensing domain with a noncovalently bound flavin mononucleotide (FMN) as its chromophore. Owing to advantages such as its small size, oxygen-independent nature, and pH stability, iLOV is an ideal candidate over other reporter fluorescent proteins such as GFP and DsRed. Here, for the first time, we describe the feasibility of applying LOV domain-based fluorescent iLOV as a metal sensor by measuring the fluorescence quenching of a protein with respect to the concentration of metal ions. In the present study, we demonstrated the inherent copper sensing property of the iLOV protein and identified the possible amino acids responsible for metal binding. The fluorescence quenching upon exposure to Cu2+ was highly sensitive and exhibited reversibility upon the addition of the metal chelator EDTA. The copper binding constant was found to be 4.72 ± 0.84 µM. In addition, Cu2+-bound iLOV showed high fluorescence quenching at near physiological pH. Further computational analysis yielded a better insight into understanding the possible amino acids responsible for Cu2+ binding with the iLOV protein.

Bioremediation of Crude Oil by White Rot Fungi Polyporus sp. S133

  • Kristanti, Risky Ayu;Hadibarata, Tony;Toyama, Tadashi;Tanaka, Yasuhiro;Mori, Kazuhiro
    • Journal of Microbiology and Biotechnology
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    • v.21 no.9
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    • pp.995-1000
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    • 2011
  • The bioremediation potential of crude oil by Polyporus sp. S133 pre-grown in wood meal was investigated in two separate experiment trials; liquid medium and soil. The effect of three nutrients (glucose, polypeptone, and wood meal), oxygen flow, and some absorbent on the efficiency of the process was also evaluated. Degradation of crude oil in soil was significantly increased with an addition of oxygen flow and some absorbent (kapok and pulp). The highest degradation rate of crude oil was 93% in the soil with an addition of 10% kapok. The present study clearly demonstrates that, if suitably developed, Polyporus sp. S133 could be used to remediate soil contaminated with crude oil.

Evaluating Bleaching Effects of a Sodium Percarbonate in the Washing Process with Enzyme Containing Detergents (효소세제에 첨가한 과탄산나트륨이 세척효과에 미치는 영향)

  • 정혜원;유지혜;방종호
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.7
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    • pp.1085-1092
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    • 2002
  • Changes in laundering habits and the efficacy claims made for oxygen bleach added to detergents necessitate a deeper investigation into the testing of the washing efficacy of detergents and washing process. The effect of the addition of a sodium percarbonate and bleach activator TAED to an enzyme containing detergent on the soil removal and antimicrobial properties were investigated with the measuring of residual H$_2$O$_2$. The addition of sodium percarbonates to enzyme containing detergent lowered the soil removal of EMPA 116 cloth. But sodium percarbonates had greater effects on that of colored stained cloths such as EMPA 115 and artificially soiled with wine and red pepper while they were presoaked at 20$^{\circ}C$ or higher for So minutes or longer. Most of hydrogen peroxide was remained after washing. Over 99.9% of Staphylococcus aureus on the cotton cloth was removed in every washing solutions, but the cloth washed with enzyme containing detergent or detergent with oxygen bleach didn't show the antimicrobial property.