• Title/Summary/Keyword: $IC_50$

Search Result 3,252, Processing Time 0.023 seconds

Potent whitening effects of rutin metabolites (루틴 대사체의 미백 효능)

  • Kim, Ji Hye;Kang, Nam Joo
    • Food Science and Preservation
    • /
    • v.22 no.4
    • /
    • pp.607-612
    • /
    • 2015
  • The aim of this research was to investigate the whitening effects of rutin and rutin metabolites including 3,4-dihydroxyphenyl acetic acid (DHPAA), 3-hydroxyphenyl acetic acid (HPAA), 3,4-dihydroxytolene (DHT) and homovanillic acid (HVA). The potent whitening effect of rutin and rutin metabolites were determined by mushroom tyrosinase inhibition assay and expressed as the half maximal inhibitory concentration ($IC_{50}$) against tyrosinase activity in vitro. The HVA showed the highest inhibitory effect ($IC_{50}=37.10{\mu}M$) of tyrosinase activity, followed by DHPAA ($IC_{50}=45.87{\mu}M$), HPAA ($IC_{50}=50.96{\mu}M$), rutin ($IC_{50}=57.98{\mu}M$), and DHT ($IC_{50}=66.09{\mu}M$), respectively. To evaluate cell cytotoxicity, MTT assay was performed with JB6 P+ mouse epidermal cells and expressed as a relative percentage of untreated control. The results showed that rutin and rutin metabolites had no cytotoxic effects on JB6 P+ cells up to $100{\mu}M$ except for DHT (up to $50{\mu}M$). These results suggests that rutin metabolites may be utilized as a potential tyrosinase inhibitors and the whitening agents for the future.

스마트 파워 IC기술

  • 황성규
    • 전기의세계
    • /
    • v.42 no.7
    • /
    • pp.30-44
    • /
    • 1993
  • 본 논단에서는 스마트 파워 IC의 개념과 주요 구성 핵심기술인 횡형 전력소자들의 기본구조와 특성을 비교하였으며, 공정에 밀접한 관련있는 전기적 격리기술, 그리고 스마트 파워 칩 구현을 위한 CAD체계에 대해 논의하였다. 또한 자동차 하이사이드 스위치와 모터 제어 및 구동용 스마트 파워 IC의 제품을 중심으로 스마트 파워 IC의 응용분야에 대해 간략하게 살펴보았다. 전자기기에 광범위하게 응용되어 시스템의 고급화, 고신뢰도 및 소형경량화에 중요한 반도체 소자를 포함한 전체 전력 반도체 소자 시장 50억불의 20%를 형성하였다. 최근 스마트 파워 IC의 큰 시트 파워 IC는 자동차 1대당 50개에서 140개까지 소요 예상되리라는 보고도 되고 있다. 스마트 파워 IC는 고내압, 대전류, 고속 스위칭 특성을 갖는 전력소자 및 전기적 격리기술 그리고 설계자동화를 위한 스마트 파워 IC의 구성 요소기술들의 지속적인 발전에 힘입어 더욱 고기능화된 제품개발에 의해 민생용 소비재 분야에서 산업분야까지 현재 보다 더 광범위한 응용이 기대된다.

  • PDF

Anticoagulant Properties of Compounds Derived from Fennel (Foeniculum vulgare Gaertner) Fruits

  • Lee, Hoi-Seon
    • Food Science and Biotechnology
    • /
    • v.15 no.5
    • /
    • pp.763-767
    • /
    • 2006
  • The anticoagulant properties of compounds derived from fennel (Foeniculum vulgare Gaertner) fruits were evaluated using a platelet aggregometer and compared with aspirin. The active constituents of fennel fruits were isolated and identified as (+)-fenchone and extragole by various spectral analysis techniques. With regard to the 50% inhibitory concentration ($IC_{50}$), (+)-fenchone effectively inhibited platelet aggregation induced by treatment with collagen ($IC_{50}$, $3.9\;{\mu}M$) and arachidonic acid (AA) ($IC_{50}$, $27.1\;{\mu}M$), and estragole inhibited collagen-induced platelet aggregation ($IC_{50}$, $4.7\;{\mu}M$). By way of comparison, (+)-fenchone and estragole proved to be significantly more potent than aspirin at inhibiting platelet aggregation induced by collagen. The inhibitory activity of (+)-fenchone toward platelet aggregation induced by AA was 1.3 times stronger than that of aspirin. These results indicate that (+)- fenchone and estragole may be useful as lead compounds for inhibiting platelet aggregation induced by arachidonic acid and collagen.

Antioxidant Activities of Medicinal Plant Extracts (약용식물 추출물의 항산화 효과)

  • Joo, Shin Youn
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.42 no.4
    • /
    • pp.512-519
    • /
    • 2013
  • The antioxidant activities of ethanolic extracts obtained from medicinal plants (Scutellaria baicalensis Georgi, Acanthopanax sessiliflorum Seeman, Pueraria lobata Ohwi, Portulaca oleracea Linne, Crataegus pinnatifida Bunge var. typica Schneider, Euonymus alatus Apterus, Hovenia dulcis Thunberg, Prunus yedoensis Matsumura, Albizzia julibrissin Durazz., Chrysanthemum indicum Linne) were evaluated for total phenolic content, total flavonoid content, DPPH radicals, nitrites, $Superoxide^-$ radicals, $ABTS^+$ radical scavenging activity, and reducing power. Antioxidant capacities were the highest in Prunus yedoensis Matsumura for DPPH radical scavenging activity ($IC_{50}$ $5.39{\mu}g/mL$), reducing power (2.72, $A_{700}$), and nitrite scavenging activity ($IC_{50}$ $167.94{\mu}g/mL$). Hovenia dulcis Thunberg and Acanthopanax sessiliflorum Seeman were effective for their nitrite scavenging activities (over 90% at 1 mg/mL). The $Superoxide^-$ radical scavenging activity of Prunus yedoensis Matsumura ($IC_{50}$ $43.39{\mu}g/mL$) was stronger than tannic acid ($IC_{50}$ $46.51{\mu}g/mL$). Five samples (Prunus yedoensis Matsumura, Acanthopanax sessiliflorum Seeman, Hovenia dulcis Thunberg, Crataegus pinnatifida Bunge var. typica Schneider, Scutellaria baicalensis Georgi) were effective for their $ABTS^+$ radical scavenging activity (more than 90% at 0.5 mg/mL). These results suggest that the ethanolic extracts of Prunus yedoensis Matsumura could be used as a functional ingredient in food products.

Isolation and Identification of α-Glucosidase Inhibitors from Morus Root Bark (상백피로부터 α-Glucosidase 저해제의 분리 및 동정)

  • Jang, Yeong Jung;Leem, Hyun Hee;Jeon, Yeong Hee;Lee, Dong Hee;Choi, Sang Won
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.44 no.7
    • /
    • pp.1090-1099
    • /
    • 2015
  • Among the four different parts of mulberry (Morus alba L.) tree, ethanol extract of Morus root bark showed the highest ${\alpha}$-glucosidase inhibitory activity ($IC_{50}=12.01{\mu}g/mL$). Bioassay-guided fractionation of the ethanolic extract of root bark by Diaion HP-20, silica gel, ODS-A, and Sephadex LH-20 column chromatographies led to the isolation of four compounds, including Compound (Comp.) 1 ($IC_{50}=5.22{\mu}g/mL$), Comp. 2 ($IC_{50}=1.78{\mu}g/mL$), Comp. 3 ($IC_{50}=2.94{\mu}g/mL$), and Comp. 4 ($IC_{50}=1.54{\mu}g/mL$) with strong ${\alpha}$-glucosidase inhibitory activities. Their chemical structures were elucidated as morusin (Comp. 1), kuwanon H (Comp. 2), chalcomoracin A (Comp. 3), and chalcomoracin B (Comp. 4) by UV and NMR spectral analyses. These results suggest that prenylflavonoid and mulberrofuran of Morus root bark may be useful as potential therapeutic agents for diabetes.

The Effects of Alpinia katsumadai Extract on Anti-inflammation and Melanogenesis

  • Lee, Jae-Soeb;Jeong, See-Hwa;Ko, Kang-Il;Kim, Ki-Ho;Chong, Chom-Kyu;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.25 no.1
    • /
    • pp.69-88
    • /
    • 1999
  • Several solvent extracts from Alpinia katsumudai were prepared and their various anti-inflammatory activities were evaluated. Alpinia katsumadai extract showed high various anti-inflammatory effects among the 8 medicinal plant extracts, Butanol extract from Alpinia katsumndai showed a potent anti-oxidative and free radical scavenging activities, Free radical scavenging effect of butanol fraction of Alpinia katsumadai($IC_{50}$/ : 50$\mu$g/m$\ell$) was higher than butylated hydroxytoluene($IC_{50}$/ : 50$\mu$g/m$\ell$) and ascorbic acid($IC_{50}$/ : 22$\mu$g/m$\ell$). Alpinia katsumadai butanol fraction exhibited relatively high antioxidative activity($IC_{50}$/ : 335$\mu$g/m$\ell$) compared to ascorbic acid. The inhibitory effect of Alpinia katsumadal ethanol extract on elastase exhibited 10 to 78% at 100 to 1000$\mu$g/m$\ell$ concentration , tile $IC_{50}$/ values with 465.7$\mu$g/m$\ell$ for porcine pancreatic elastase(PPE) and 481.9$\mu$g/m$\ell$ for human leukocyte elastase(HLE), respectively The Alpinta katsumadai extract inhibited effectively hyaluronidase activity($IC_{50}$/ 335$\mu$g/m$\ell$), and showed inhibition in vitro on delayed hypersensitivity when it was topically applied. These results suggest that Alpinia katsumadai extract may reduce inflammatory skin trouble. The Alpinia katsumadai extract also showed higher Inhibitory effect of melanin biosynthesis on cultured melanoma cell compared to arbutin and kojic acid.

  • PDF

The Anti-melanogenic Effect of Geranium krameri Extract (선이질풀 추출물의 멜라닌 생성 억제 효과)

  • Kim, Hyun-Soo
    • Korean Journal of Food Science and Technology
    • /
    • v.48 no.1
    • /
    • pp.72-76
    • /
    • 2016
  • We investigated the application of functional materials by examining a variety of physiological activities of Geranium krameri extract obtained from the National Institute of Horticultural and Herbal Science. Geranium krameri extract had a low cytotoxicity against murine melanoma B16F10 cells. At concentrations with little or no cytotoxicity, Geranium krameri extract showed high DPPH radical scavenging activity ($IC_{50}$, $8.72{\mu}g/mL$) and anti-microbial activities against Bacillus subtilis, Escherichia coli, and Candida albicans. Additionally, Geranium krameri extract inhibited tyrosinase activity ($IC_{50}$, $456.86{\mu}g/mL$) and decreased melanin content ($IC_{50}$, $50.35{\mu}g/mL$). The treatment of B16F10 cells with Geranium krameri extract suppressed the protein expression of tyrosinase in a dose-dependent manner. These findings suggest that Geranium krameri extract inhibits melanin synthesis in murine melanoma B16F10 cells by suppressing intracellular tyrosinase expression, as well as directly inhibits tyrosinase activity simultaneously.

Effects of baicalein on hydrogen peroxide productions in RAW 264.7 mouse macrophages stimulated by poly-IC and lipoteichoic acid (바이칼레인(baicalein)이 poly-IC와 lipoteichoic acid로 자극된 마우스 대식세포 RAW 264.7의 hydrogen peroxide 생성에 미치는 영향)

  • Wansu Park
    • The Korea Journal of Herbology
    • /
    • v.38 no.4
    • /
    • pp.11-19
    • /
    • 2023
  • Objectives : The aim of this study was to investigate the effect of baicalein (BA) on the production of hydrogen peroxide and nitric oxide (NO) in RAW 264.7 mouse macrophages stimulated with polyinosinic-polycytidylic acid (poly-IC) and lipoteichoic acid. Methods : RAW 264.7 co-stimulated with poly-IC and lipoteichoic acid were incubated with baicalein at concentrations of 25 and 50 μM. Incubation time is 16 h, 18 h, 20 h, 22 h, and 24 h. After incubation, The production of hydrogen peroxide in RAW 264.7 was measured with dihydrorhodamine 123 assay. Chrysin was used as a comparative material. NO production was evaluated by griess assay. Results : For 16 h, 18 h, 20 h, 22 h, and 24 h incubation, BA at the concentration of 25 and 50 μM significantly inhibited the production of hydrogen peroxide in RAW 264.7 stimulated by poly-IC and lipoteichoic acid (p <0.001). In details, production of hydrogen peroxide in 'poly-IC and lipoteichoic acid'-stimulated RAW 264.7 treated for 16 h with BA at concentrations of 25 and 50 μM was 82.36% and 77.24% of the control group treated with poly-IC and lipoteichoic acid only, respectively; the production of hydrogen peroxide for 18 h was 83.15% and 77.91%, respectively;production of hydrogen peroxide for 20 h was 82.88% and 77.82%, respectively; production of hydrogen peroxide for 22 h was 83.27% and 78.17%, respectively; production of hydrogen peroxide for 24 h was 83.54% and 78.35%, respectively. Additionally, BA at the concentration of 50 and 100 μM significantly inhibited NO production in lipoteichoic acid-induced RAW 264.7 (p <0.001). Conclusions : BA might have anti-oxidative activity related to its inhibition of hydrogen peroxide production in 'poly-IC and lipoteichoic acid'-stimulated RAW 264.7 macrophages.

IEEE 1500 Wrapper Design Technique for Pre/Post Bond Testing of TSV based 3D IC (TSV 기반 3D IC Pre/Post Bond 테스트를 위한 IEEE 1500 래퍼 설계기술)

  • Oh, Jungsub;Jung, Jihun;Park, Sungju
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.50 no.1
    • /
    • pp.131-136
    • /
    • 2013
  • TSV based 3D ICs have been widely developed with new problems at die and IC levels. It is imperative to test at post-bond as well as pre-bond to achieve high reliability and yield. This paper introduces a new testable design technique which not only test microscopic defects at TSV input/output contact at a die but also test interconnect defects at a stacked IC. IEEE 1500 wrapper cells are augmented and through at-speed tests for pre-bond die and post-bond IC, known-good-die and defect free 3D IC can be massively manufactured+.

Alpha-glucosidase Inhibition Activity of Methanol Extracts Obtained from Nine Pteridophyte Species Native to Korea (자생 양치식물 9종의 성엽 및 근경 추출물의 α-glucosidase 억제 활성)

  • Kim, Na Rae;Chi, Lai Won;Lee, Cheol Hee
    • Korean Journal of Plant Resources
    • /
    • v.26 no.4
    • /
    • pp.411-416
    • /
    • 2013
  • This study was conducted not only to analyze ${\alpha}$-glucosidase inhibition activity with fronds and rhizomes of nine Pteridophyte species, but also to select the plant materials suitable for natural ${\alpha}$-glucosidase inhibitor. Harvested rhizomes and fronds were washed, freeze-dried and grinded. After conducting ultrasonification extraction for 30 minutes in ultrasonic water tank with 100% methanol solvent, and vacuum filtration, ${\alpha}$-glucosidase inhibition activity was measured. Acarbose was used as the positive control. After mixing $100{\mu}L$ of 0.7 unit ${\alpha}$-glucosidase enzyme solution into $50{\mu}L$ of extract and reacting them at $37^{\circ}C$ for 10 minutes, $50{\mu}L$ of 1.5 mM ${\rho}$-NPG solution was taken and reacted at $37^{\circ}C$ for 20 minutes. The reaction was stopped with 1 mL of 1 M $Na_2CO_3$ and absorbance was measured in 405 nm. With the regression analysis, the content of solubility solids (the value of $IC_{50}$) which can inhibit 50% of 0.7 unit ${\alpha}$-glucosidase solution's activity was investigated. The frond ($IC_{50}=14.00{\sim}913.33{\mu}g{\cdot}mL^{-1}$) and rhizome extracts ($IC_{50}=12.93{\sim}205.84{\mu}g{\cdot}mL^{-1}$) of nine Pteridophyte species showed higher ${\alpha}$-glucosidase inhibition activity in comparison with acarbose ($IC_{50}=1413.70{\mu}g{\cdot}mL^{-1}$). The extracts of fronds and rhizomes showed higher value than acarbose by 1.55~100.98 and 6.87~109.33 times each. Especially, ${\alpha}$-glucosidase inhibition activities of Pyrrosia lingua in fronds and Osmunda cinnamomea var. fokiensis in rhizomes were the highest. The necessary biomass of fronds and rhizomes for inhibiting 50% of ${\alpha}$-glucosidase activity showed the lowest value, 0.35, 0.27 mg each, in O. cinnamomea var. fokiensis. $IC_{50}$ value of P. lingua was the highest among fronds of nine Pteridophyte species, but content of soluble solids was 2.4 times less than O. cinnamomea var. fokiensis. So frond of O. cinnamomea var. fokiensis is more economic in comparison with P. lingua. As the result of this study, O. cinnamomea var. fokiensis showed high ${\alpha}$-glucosidase inhibition activity even with small biomass. Therefore it was considered to be high-valued economic material as natural ${\alpha}$-glucosidase inhibitor.