• Title/Summary/Keyword: oxygen concentration

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Antioxidative Effect and Component Analysis of Eriobotrya japonica Leaf Extracts (비파엽 추출물의 항산화 효능과 성분분석)

  • Kim, Su-Ji;Park, Jin-O;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.1
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    • pp.57-65
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    • 2012
  • In the present study, the antioxidative properties, inhibitory activity on tyrosinase, and active components of Eriobotrya japonica (E. japonica) leaf extract were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$) of extract/fraction of E. japonica leaf was in the order 50 % ethanol extract ($22.625{\mu}g/mL$) < ethyl acetate fraction (6.75) < deglycosylated aglycone fraction (5.06). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of fraction/extracton ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescenceassay were investigated. $OSC_{50}$ of the ethyl acetate fraction, deglycosylated aglycone fraction, and ethanol extract were 0.75, 0.79, and $1.61{\mu}g/mL$, respectively. The cellular protective effects of E. japonica leaf extract on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The protective effects of extract/fraction of E. japonica leaf were increased in a in a concentration dependent manner ($5{\sim}50{\mu}g/mL$). Especially, ${\tau}50$ of ethyl acetate fraction at concentrations of $10{\mu}g/mL$ and $50{\mu}g/mL$ showed the most protective effects at 390.8 min and 1471.5 min. The inhibitory effect ($IC_50$) on tyrosinase of E. japonica leaf extracts was higher than arbutin, known as a skin-whitening agent. The order of inhibitory effects was acetate fraction ($75.25{\mu}g/mL$) < 50 % extract (74.1) < deglycosylated aglycone fraction (43.35). TLC of the ethyl acetate fraction showed 7 bands (EJL 1 - EJL 7). HPLC of the aglycone fraction exhibited 2 peaks, kaempferol and quercetin. The amounts of kaempferol and quercetin were 53.7 and 46.3 %. respectively. Therefore, The amounts of kaempferol and its glucoside were a little bit higher than quercetin and its glucoside in E. japonica leaf extract. Accordingly, these findings suggest that extracts/fractions of E. japonica leaf can function as antioxidants in biological systems, especially skin exposed to UV radiation, and protect cellular membranes against ROS. Thus, the extract/fraction of E. japonica leaf may be used in novel functional cosmetics as antioxidants against skin photoaging.

Antioxidative Properties of Extract/Fractions of Suaeda asparagoides and Salicornia herbacea Extracts(I) (함초(나문재 및 퉁퉁마디) 추출물의 항산화 작용에 관한 연구(I))

  • Park, Soo-Nam;Jeon, So-Mi;Kim, So-I;Ahn, Jeung-Youb
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.33 no.3
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    • pp.145-152
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    • 2007
  • In this study, the antioxidative effects of Sueada asparagoides and Salicornia herbacea extracts were investigated. The free radical(1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity($FSC_{50}$) of extract/fractions of Sueada asparagoides was in the order: 100 % ethanol extract(329.33 ${\mu}g/mL$) < 50 % ethanol extract(40.73) < ethylacetate fraction(13.87) < deglycosylated aglycone fraction (7.80). In case of Salicornia herbacea, the free radical scavenging activities of ethylacetate fraction and aglycone fraction were 13.87 and 7.80 ${\mu}g/mL$, respectively. Reactive oxygen species(ROS) scavenging activities($OSC_{50}$) of Sueada asparagoides and Solicornia herbacea extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity of Sueada asparagoides extracts was 50 % ethanol extract($OSC_{50}$, $0.99{\mu}g/mL$) < ethylacetate fraction (0.05) < aglycone fraction (0.03). Aglycone fraction showed the most prominent scavenging activity. In case of Salicornia herbacea, the ROS scavenging activities of ethylacetate fraction and aglycone fraction were 0.10 and 0.20 ${\mu}g/mL$, respectively. The protective effects of extract/fractions of Sueada asparagoides and Salicornia herbacea on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethanol extract(100%) of Sueada asparagoides diminished photohemolysis in a concentration dependent manner($1{\sim}100{\mu}g/mL$). Particularly deglycosylated aglycone fraction exhibited the most prominent celluar protective effect($\tau_{50}$, 310 min at 50 ${\mu}g/mL$). In case of Salicornia herbacea, ethylacetate fraction exhibited more potent protective effect. These results indicate that extract/fractions of Sueada asparagoides can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS.

The Role of Cyclooxygenase Metabolites in the Pathogenetic Mechanism of Endotoxin-Induced Acute Lung Injury in Domestic Pigs (내독소에 의한 돼지의 급성 폐손상에서 Cyclooxygenase 대사물의 역할에 관한 연구)

  • Yoo, Chul-Gyu;Jeong, Ki-Ho;Choi, Hyung-Seok;Lee, Hyuk-Pyo;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
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    • v.39 no.1
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    • pp.42-54
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    • 1992
  • Background:It has been suggested that the cyclooxygenase metabolites play an important role in changes of early hemodynamic parameters in the endotoxin-induced acute lung injury. But there have been many debates about their role in the late increase of alveolar-capillary permeability, and it is not known whether they act directly or indirectly through oxygen free radicals which have been known to be produced during the metabolic process of cyclooxygenase pathway. So we performed this study to identify the pathogenetic role of cyclooxygenase metabolites in the endotoxin-induced acute lung injury in domestic pigs. Method: We infused endotoxin into 8 domestic pigs; endotoxin only (n=3), and pretreatment with indomethacin (n=5). We observed the sequential changes in hemodynamic parameters, the concentration of plasma oxidized glutathione (GSSG) in pulmonary arterial and venous blood, and albumin content in bronchoalveolar lavage fluid (BALF). Results: 1) While cardiac output decreased, mean pulmonary arterial pressure, pulmonary vascular resistance, and alveolar-arterial oxygen difference increased over phase 1 (0-2hr) and phase 2 (2-4.5hr) by endotoxin, indomethacin attenuated the decrease in cardiac output during phase 1 and increase in mean pulmonary arterial pressure, pulmonary vascular resistance, and alveolar-arterial oxygen difference during both phases. 2) The increase in plasma GSSG content during phase 2 was not attenuated by indomethacin. 3) The content of BALF albumin was significantly lower in indomethacin groups than that of endotoxin group. Conclusion: These results suggest that it is likely that cyclooxygenase metabolites have an effect on endotoxin-induced acute lung injury during both phases probably through direct action.

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Oxide perovskite crystals type ABCO4:application and growth

  • Pajaczkowska, A.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.258-292
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    • 1996
  • In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

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Antioxidant Activity of Persicaria perfoliata Extracts (며느리배꼽 추출물의 항산화 활성)

  • Ahn, You-Jin;Kim, Sun-Young;Ok, Ju-Hyung;Wang, Hyun;Park, Chang-Hwa;Kim, Sung-Ho;Heo, Yun-Suk;Jeon, Young-Hee;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.35 no.3
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    • pp.235-241
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    • 2009
  • In this study, the antioxidative effects, inhibitory effects on tyrosinase, elastase of Persicaria perfoliata extracts were investigated. The deglycosylated fraction of extract ($12.38{\mu}g$/mL) showed the most prominent free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of P. perfoliata extracts on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of extract ($0.35{\mu}g$/mL) showed the most prominent ROS scavenging activity. The protective effects of P. perfoliata extract/fractions on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The P. perfoliata extracts suppressed photohemolysis in a concentration dependent manner ($1{\sim}50{\mu}g$/mL) except the deglycosylated fraction of extract. The inhibitory effect of P. perfoliata extracts on tyrosinase was investigated to assess their whitening efficacy. Inhibitory effects ($IC_{50}$) on tyrosinase were determined with ethyl acetate fraction of P. perfoliata extract ($136.00{\mu}g$/mL) and deglycosylated fraction of extract ($68.10{\mu}g$/mL). Finally, their anti-elastase activities were measured to predict the anti-wrinkle efficacy in the human skin. Inhibitory effects ($IC_{50}$) on elastase were determined with ethyl acetate fraction of P. perfoliata extract ($67.20{\mu}g$/mL) and deglycosylated fraction of extract ($43.50{\mu}g$/mL). These results indicate that extract/fractions of P. perfoliata can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS. Extract/fractions of P. perfoliata can be applicable to new functional cosmetics for antioxidant, antiaging.

Antibacterial and Antioxidative Activities of Inula britannica Flower Extract (금불초 꽃 추출물의 항균 및 항산화 활성)

  • Kim, Eun-Hee;Kim, Jung-Eun;Kim, Kyu-Hee;Na, Eui-Yeon;Lee, Sang-Ki;Jeong, Hyun-Min;Lee, Hyun-Jun;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.35 no.3
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    • pp.209-217
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    • 2009
  • In this study, the antibacterial activity, antioxidative effects, inhibitory effects on tyrosinase of Inula britannica flower extracts were investigated. MIC values of ethyl acetate fraction from Inula britannica flower on P. acnes 0.25 %, respectively. The results showed that the antibacterial activity of the ethyl acetate fraction was the highest in the P. acnes. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities ($FSC_{50}$) of ethyl acetate fraction of Inula britannica flower was $8.55{\mu}g$/mL. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of some fInula britannica flower extracts on ROS generated in $Fe^{3+}$- EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activities were ethyl acetate fraction $0.24{\mu}g$/mL. Ethyl acetate fraction showed the most prominent ROS scavenging activity. The protective effects of extract/fractions of Inula britannica flower on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The Inula britannica flower extracts suppressed photohemolysis in a concentration dependent manner ($5{\sim}100{\mu}g$/mL), particularly deglycosylated flavonoid aglycone fraction exhibited the most prominent celluar protective effect ($\tau_{50}$, 164.15 min at $25{\mu}g$/mL). The inhibitory effect of Inula britannica flower extracts on tyrosinase was investigated to assess their whitening efficacy. Inhibitory effects ($IC_{50}$) on tyrosinase of some Inula britannica flower extracts were high. Ethyl acetate fraction has $IC_{50}$ of $87.03{\mu}g$/mL. These results indicate that extract/fractions of Inula britannica flower can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS. And inhibitory activity on tyrosinase of the ethyl acetate fraction and high potential as bactericide against the skin pathogenic bacteria could be applicable to new functional cosmetics for antioxidant, antiaging, antibacterial activity.

Ammonia Removal Capacities of Several Filter Media in a Seawater Recirculating Aquaculture System (해수 순환 여과 양식 시설의 여과 재료별 암모니아 제거 능력)

  • 전임기;손맹현;조재윤;이종문
    • Journal of Aquaculture
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    • v.10 no.3
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    • pp.261-271
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    • 1997
  • Ammonia removal capacities of five submerged filter media, 2~3mm sand, 30~50mm gravel, 20~40mm coral sand, polythylene net, and corrugated plastic plate in a seawater recirculating system were tested. A rotating biological contactor (RBC) was also tested for comparison. Oxygen consumption rates were measured along with the ammonia removal efficiencies. The ammonia concentrations in the system were maintained from 0.052 to 0.904 mg/l (mean 0.338$\pm$0.219 mg/l) and the water temperature was ranged from 19.2 to $21.4^{\circ}C\;(mean 20.2^{\circ}C\pm0.58^{\circ}C$). The 1/2-order kinetic model (Y:g/$m^3$/day) and the mean ammonia removal rates (g/$m^3$/day) of the filter media were : Sand : Y=135.5X0.5-25.1(r2=0.8110), 45.1 Coral sand : Y=125.1X0.5-33.0 (r2=0.7307), 31.8 Polyethylene net : Y=87.4X0.5-20.1 (r2=0.6780), 25.2 Corrugated plastic plate : Y=87.4X0.5-20.1(r2=0.5206), 19.2 Gravel : Y=4307X0.5-5.5 (r2=0.2596), 17.1 RBC : Y=127.6X0.5-33.4 (r2=0.7146), 32.8 where X is the concentration of ammonia. Oxygen consumption rates well corresponded to the ammonia removal capacities of each filter medium, thus the sands showing the highest value (442g/$m^3$/day) followed by coral sands (291.1g/$m^3$/day), polyethylene nets (236.9g/$m^3$/day), gravels (135.6g/$m^3$/day) and corrugated plastic plates (134.2g/$m^3$/day). Oxygen consumption rate of the RBC was unable to measure because of the characteristics of the structure.

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Licochalcone C Induces Autophagy in Gefitinib-sensitive or-resistant Human Non-small Cell Lung Cancer Cells (Gefitinib-민감성 또는 내성 비소세포폐암 세포에서 Licochalcone C에 의한 자가포식 유도)

  • Oh, Ha-Na;Yoon, Goo;Chae, Jung-Il;Shim, Jung-Hyun
    • Journal of Life Science
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    • v.29 no.12
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    • pp.1305-1313
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    • 2019
  • Licochalcone (LC), isolated from the roots of Glycyrrhiza inflata has multiple pharmacological effects including anti-inflammatory and anti-tumor activities. To date, Licochalcone C (LCC) has induced apoptosis and inhibited cell proliferation in oral and bladder cancer cells, but lung cancer has not yet been studied. In addition, no study reported LCC-induced autophagy in cancer until now. The present study was designed to investigate the effect of LCC on gefitinib-sensitive and -resistant lung cancer cells and elucidate the mechanism of its action. The 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay data showed that LCC significantly inhibited cell viability in non-small cell lung cancer (NSCLC) HCC827 (gefitinib-sensitive) and HCC827GR (gefitinib-resistant) cell lines. Interestingly, Annexin V/7-aminoactinomycin D double staining and cell cycle analysis showed an apoptosis rate within about 20% at the highest concentration of LCC. LCC induced G2/M arrest by reducing the expression of the cell cycle G2/M related proteins cyclin B1 and cdc2 in NSCLC cell lines. Treatment of LCC also induced autophagy by increasing the expression of the autophagy marker protein microtubule-associated protein 1 light chain 3 (LC3) and the protein autophagy-related gene 5 involved in the autophagy process. In addition, LCC increased the production of reactive oxygen species (ROS), and the cell viability was partially restored by treatment with the ROS inhibitor N-acetyl-L-cysteine. In western blotting analysis, the expression of cdc2 was increased and LC3 was decreased by the simultaneous treatment of NAC and LCC. These results indicate that LCC may contribute to anti-tumor effects by inducing ROS-dependent G2/M arrest and autophagy in NSCLC. In conclusion, LCC treatment may be useful as a potential therapeutic agent against NSCLC.

Antioxidative Activity and Componential Analysis of Chamaecyparis obtusa Leaf Extract (편백나무 잎 추출물의 항산화 활성과 성분분석에 관한 연구)

  • Lee, Dong Sook;Lim, Myoung Sun;Kwan, Soon Sik;Kim, Sun Young;Park, Soo Nam
    • Applied Chemistry for Engineering
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    • v.23 no.1
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    • pp.93-99
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    • 2012
  • In this study, the evaluation of antioxidative activity and componential analysis of C. obtusa leaf extracts was carried out. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of C. obtusa leaf extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction ($OSC_{50}$; 0.22 ${\mu}g/mL$) and aglycone fraction of C. obtusa leaf extracts (0.20 ${\mu}g/mL$) showed about 7 times more prominent ROS scavenging activity than L-ascorbic acid (1.50 ${\mu}g/mL$). The cellular protective effects of fractions obtained from C. obtusa leaf extracts on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethyl acetate fraction and aglycone fraction of C. obtusa leaf extracts showed the cellular protective effects in a concentration dependent manner (5~25 ${\mu}g/mL$). The inhibitory effect ($IC_{50}$) of ethyl acetate fraction and aglycone fraction on tyrosinase exhibited 74.43 and 53.80 ${\mu}g/mL$, repectively. The aglycone fraction showed four times higher tyrosinase inhibitory effect than arbutin (226.88 ${\mu}g/mL$), known as a whitening agent. The aglycone fraction of C. obtusa leaf extracts showed three bands in TLC chromatogram and three peaks in HPLC chromatogram (360 nm). Three compounds were identified as taxifolin, quercetin and kaempferol. These results indicate that the fractions of C. obtusa leaf extracts can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against reactive oxygen species. The fractions of C. obtusa leaf extracts can be applicable to new functional cosmetics for antioxidan and whitening effects.

The Responses of Particulate Phosphorus Exposed to the Fresh Water in Marine Sediment (담수화로 인한 퇴적물 내 입자성 인의 거동에 관한 실험적 연구)

  • Ji, Kwang-Hee;Jeong, Yong-Hoon;Kim, Hyun-Soo;Yang, Jae-Sam
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.2
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    • pp.84-90
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    • 2009
  • We incubated marine columnar sediments at $25^{\circ}C$ for 230 days to simulate the responses of phosphorus in the sediment which was exposed to freshwater. The incubation was composed of three different treatments (FW: freshwater, FWA: freshwater under anoxic condition, and SW: seawater as a Control). Six particulate fractions of phosphorus in sediment were obtained through sequential extraction and, for comparison, phosphate concentrations in porewater and superlying water were also determined. After the incubation, evidently higher concentrations of phosphate were found in FW and FWA compared to SW. Mass extinction of living organisms in marine sediment from freshwater shock and consequent decay of their corps probably contributed such high phosphate spike in the overlying water. Higher concentrations of BD-P(lron-bound P) were found in FW compared to SW. After exposure to the freshwater, we could determine that penetration depth of dissolved oxygen in marine sediment will be deeper. A result of increases of ferrous compounds in freshwater where contained less sulfide has been obtained. Because of these phenomena, BD-P was increased in FW. On the contrary, BD-P was decreased in FWA since poor dissolved oxygen concentration. In FWA, total amount of Leachable P(SUM of LOP) has been remarkably increased through the experiment, which strongly suggested the easy conversion of the leachable P into reactive P. This experiment has shown that most of diverse P species in marine sediment were leachable under freshwater and low oxygen condition. Therefore reclamation of natural tidalfalt and consequent freshwater introduction seems to trigger the conversion of diverse P-species to leachable P in the marine sediments, which will exert high benthic load of phosphate to the overlying water.

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