• Title/Summary/Keyword: Reactive Power Control

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Whitening and Antioxidant Effects of a Mixture of Poria cocas, Glycyrrhiza uralensis, and Ulmus macrocarpa Extracts (미백과 항산화에 미치는 백복령, 감초, 유백피 추출 혼합물의 영향)

  • Kwon, Eun-Jeong;Park, Hye-Jung;Nam, Hyang;Lee, Su-Gyeng;Hong, Su-Gyoung;Kim, Moon-Moo;Lee, Kyeong Rok;Hong, Il;Lee, Do Gyeong;Oh, Yunghee
    • Journal of Life Science
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    • v.24 no.10
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    • pp.1063-1069
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    • 2014
  • Reactive oxygen species (ROS) are known to lead to oxidation of lipids, proteins, and DNA and cause skin damage. Moreover, ROS promote melanogenesis, which causes melasma, age spots, and freckle. The main compounds of the herbal medicines Poria cocas, Glycyrrhiza uralensis, and Ulmus macrocarpa were reported to be parchymic acid, glabridin, and flavonoids, respectively. The aim of this study was to investigate the whitening and antioxidant effects of a mixture of P. cocas, G. uralensis, and U. macrocarpa extracts (PGUE) in B16F1 cells to develop whitening cosmetics. PGUE inhibited DPPH radicals and lipid peroxidation, in addition to high reduction power, compared with Glycyrrhiza uralensis ethylacetate extracts (GUEE). Furthermore, PGUE exhibited a protective effect against DNA oxidation induced by the hydroxyl radicals. In addition to its antioxidant activity, the inhibitory activity of PGUE against tyrosinase, which is associated with melanogenesis, was greater than that of arbutin used as a positive control. Moreover, PGUE exerted an inhibitory effect on melanin synthesis in live melanoma cells and reduced the expression levels of superoxide dismutase-1 (SOD-1) and tyrosinase related protein-1 (TRP-1). These results indicate that PGUE has skin whitening and antioxidant effects, suggesting that this mixture can be used as the main ingredient in the development of effective whitening cosmetics.

Plasma Etching Characteristics of Sapphire Substrate using $BCl_3$-based Inductively Coupled Plasma ($BCl_3$ 계열 유도결합 플라즈마를 이용한 사파이어 기판의 식각 특성)

  • Kim, Dong-Pyo;Woo, Jong-Chang;Um, Doo-Seng;Yang, Xue;Kim, Chang-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.363-363
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    • 2008
  • The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

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Oxidation Stability of Lavers Made with Garlic-Salt and Their Characteristics during Storage (마늘맛 조미 김의 산화안전성 및 저장특성 연구)

  • Jeon, Ye-Sook;Park, Soo-Jin;Choi, Mi-Kyeong;Kang, Myung-Hwa
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.1
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    • pp.83-89
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    • 2008
  • In order to evaluate the oxidation stability, chemical compounds, and sensory for the garlic-salt laver, we prepared the garlic-salt laver added with different levels of salt and garlic power. The lipid per oxidation of garlic-salt laver was monitored by measuring the formation of 2-thiobarbituric acid reactive substances (TBARS). In addition, the general chemical compounds of laver with garlic-salt were determined by moisture, crude lipid ash, and protein. The major tocopherol compounds of laver with garlic-salt were measured using HPLC system. The contents of ${\alpha}$-tocopherol decreased with time, in contrast to ${\gamma}$-tocopherol which increased with time. The lipid profiles of laver with garlic-salt were high in linoleic acid although they did not change with time. Formation of TBARS of laver increased in control but did not increase in laver with garlic-salt. After 12 weeks, laver with 33% garlic-salt showed strong inhibition effect on TBARS formation. The sensory evaluation of laver with garlic-salt were tested. The results seem to indicate that laver with 33% garlic-salt can be used as a good ratio.

Evaluation of Antioxidant Activity in Pork Patties Containing Bokbunja (Rubus coreanus) Extract (복분자 추출물을 첨가한 돈육패티의 항산화 활성평가)

  • Park, Sun-Young;Chin, Koo-Bok
    • Food Science of Animal Resources
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    • v.27 no.4
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    • pp.432-439
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    • 2007
  • This study was performed to investigate the physicochemical properties and antioxidative activities of water or methanol extracts of Bokbunja (Rubus coreanus), and pork patties containing bokbunja extract at various levels. The total phenolic content of methanol extract (6.76 g/100 g, dry base) was higher than that of water extract (3.38 g/100 g, dry base). In addition, methanol extract had higher 1,1'-diphenyl-2-picrylhdrazyl (DPPH) radical scavenging activity than water extract at low concentrations (0.025-0.1%). However, no significant differences were found at high concentrations (0.2% or higher) (p>0.05). The DPPH radical scavenging activities of methanol and water extracts were 76.97% and 74.87% at 0.2% level, respectively. The lightness and yellowness values of pork patties containing Bokbunja extract decreased with increasing concentrations. The thiobarbituric acid reactive substances (TBARS) in pork patties with Bokbunja extract were lower than that of the control (p<0.05). The antioxidative activities increased with increasing concentrations of Bokbunja extract. In conclusion, Bokbunja extract might be used as a natural antioxidant in meat products, however levels lower than 3% will be required to prevent quality defects in pork patties.

A Study on Antioxidant and Antibacterial Efficacy Evaluation and Cosmetic Application of Rumex crispus L. Root Extract (소루쟁이 뿌리 추출물(Rumex crispus L.)의 라디칼 소거능과 항균력 평가 및 화장품 적용 가능성에 관한 연구)

  • Yu-Jin Park;Jae-Chan Yang
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.2
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    • pp.159-171
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    • 2024
  • This study confirmed the antioxidant activity and antimicrobial efficacy and formulation stability for the effectiveness experiment of Rumex crispus. L root extract. For antioxidant activity, DPPH radical scavenging, FRAP activity, ABTS+ radical scavenging, and SOD-like activity were performed. Antimicrobial activity was evaluated for Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans strains. In addition, skin containing Rumex crispus. L root extract is checked over time for pH, temperature, and daylight for 21 days. As a result of antioxidant evaluation, it was confirmed that the activity increased in a concentration-dependent manner at a concentration of 0.0625-1 mg/mL. The clear zones of each bacterium at 100mg/mL concentrations were 10.45±0.34, 9.77±0.59, 9.92±0.22, and 10.08±0.12, which were superior to the control group Methyl paraben, and the antibacterial power of S. aureus and E. coli was confirmed at 100mg/mL concentration for MIC. There was little change in absorbance when the pH of the skin was 4.0, 6.0, and 7.0 and At 4℃, 25℃, and 40℃, it was discolored as the temperature increased. It was also observed that discoloration occurred when exposed to daylight. This is presumed to be able to prevent discoloration when it is shielded and stored at low temperatures. When the results of this study are summarized, Rumex crispus. L root extract is considered to have high value in use as a cosmetic raw material that can expect antioxidant and antibacterial activities.

Suppressive effects of ethanol extract of Aralia elata on UVB-induced oxidative stress in human keratinocytes (자외선 B를 조사한 인간유래각질세포에서 두릅순 에탄올추출물의 산화적 스트레스 억제효과)

  • Kwak, Chung Shil;Yang, Jiwon
    • Journal of Nutrition and Health
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    • v.49 no.3
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    • pp.135-143
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    • 2016
  • Purpose: Ultraviolet (UV)-induced oxidative stress contributes to several adverse biological effects on skin. Many phenolic phytochemicals have been shown to have antioxidant properties and protect skin cells from UV-induced oxidative damage. In this study, we investigated whether or not Aralia elata (AE) has a protective effect against UVB-induced reactive oxygen species (ROS), ultimately leading to photoaging. Methods: Phenolic content of dried AE and antioxidant properties of AE extract in 70% ethanol weredetermined by measuring DPPH and ABTS radical scavenging activities and ferric reducing antioxidant power (FRAP). The effect of AE extract on cellular ROS generation and expression levels of oxidative stress-response proteins such as superoxide dismutase (SOD)-1, catalase, nuclear factor-erythroid 2-related factor (Nrf)-2, and heme oxygenase (HO)-1 in UVB-irradiated ($75mJ/cm^2$) human keratinocytes (HaCaT) were further determined by 2'-7'-dichlorofluoresceine diacetate assay and Western blotting, respectively. Results: The total phenolic and flavonoid contents of dried AE were 20.15 mg tannic acid/g and 18.75 mg rutin/g, respectively. The $IC_{50}$ of AE extract against DPPH radical was $98.5{\mu}g/mL$, and ABTS radical scavenging activity and FRAP upon treatment with $1,000{\mu}g/mL$ of AE extract were $41.8{\mu}g\;ascorbic\;acid\;(AA)\;eq./mL$ and $29.7{\mu}g\;AA\;eq./mL$,m respectively. Pretreatment with AE extract significantly reduced (p < 0.05) ROS generation compared to that in UVB-irradiated control HaCaT cells. Pretreatment with AE extract reversed reduction of Nrf-2 and SOD-1 protein expression and induction of HO-1 protein expression caused by UVB exposure in HaCaT cells, whereas it did not affect catalase expression. Conclusion: AE extract in 70% ethanol demonstrated a protective effect against UVB-induced oxidative stress and decreased expression of Nrf-2 and SOD-1 in human keratinocytes. These findings suggest that AE ethanol extract might have potential as a natural resource for a skin anti-photoaging product in the food and cosmetic industry.