• Title/Summary/Keyword: Reactive Power Control

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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.

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.