• Title/Summary/Keyword: $G_{IC}$

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Screening of Herbal Medicines for Phosphodiesterase 5 Inhibitor (약용식물로 부터의 Phosphodiesterase 5 저해제 검색)

  • Lee, Keyong-Ho;Kim, Byeong-Soo;Rhee, Ki-Hyeong
    • Korean Journal of Pharmacognosy
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    • v.43 no.2
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    • pp.184-191
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    • 2012
  • The aim of this study was to explore the potent phosphodiesterase type 5 (PDE %) inhibitor from various herbal medicines for erectile dysfunctions. In this study, 61 herbal medicines, which were extracted with ethanol, have been investigated with PDE 5 assay using enzyme inhibitory activity on 22 species of herbal medicines. Of these, 5 species of herbal medicines, Cnidium monieri, Cuscuta chinensis, Epimedium koreanum, Morinda officinalis, and Tribulus terrestris were exhibited stronger inhibitory effect against phosphodiesterase 5 (PDE 5) among 61 species; Cnidium monieri ($IC_{50}=33.7{\mu}g/ml$), Cuscuta chinensis ($IC_{50}=65.7{\mu}g/ml$), Epimedium koreanum ($IC_{50}=90.3{\mu}g/ml$), Morinda officinalis ($IC_{50}=48.7{\mu}g/ml$) and Tribulus terrestris ($IC_{50}=32.5{\mu}g/ml$).

$G_IC$ determination of unidirectional graphite /epoxy DCB composites from the elastic work factor approach (탄성일인자방법을 적용한 단일방향 탄소섬유/에폭시 DCB 시편의 파괴인성 결정)

  • Rhee, Kyeong-Yeop;Lee, Joong-Hee
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.22 no.3
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    • pp.540-544
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    • 1998
  • Compliance calibration method is frequently used to determine $G_IC$ from the DCB composite specimen. However, the method requires at least 4 to 5 fracture test (loading-unloading) records. In this study, $G_IC$ of unidirectional graphite/epoxy DCB composites was determined from the elastic work factor approach which uses a single fracture test record. In order to inspect the validity of the elastic work factor approach, $G_IC$ determined from the elastic work factor approach was compared to that of determined from the compliance calibration method. It was shown that $G_IC$ determined from the elastic work factor approach was comparable to that determined from the compliance calibration method. That is, the elastic work factor approach can be used to determine $G_IC$ of unidirectional graphite/epoxy DCB specimen from a single fracture record.

J-Integral Evaluation of Concrete Fracture Characteristics

  • Choi, Sin-Ho;Kye, Hae-Ju;Kim, Wha-Jung
    • International Journal of Concrete Structures and Materials
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    • v.18 no.3E
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    • pp.183-189
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    • 2006
  • Many researchers have recently proposed various parameters, variables of models and experimental methods to evaluate fracture properties of concrete, and their developments allow us to analyze the non-linear and quasi-brittle fracture mechanisms. This paper presents a brief treatment of the fracture parameters. Additionally, three-point bending tests were conducted to compare J-integral($J_{Ic}$) with other parameters($K_{Ic},\;G_{Ic},\;and\;G_F$). The change in parameter values with respect to the width and notch length of concrete beam specimens was also considered. The load-displacement curves were used to measure the concrete fracture toughness experimentally. From the results of experiment, it was found that the value of $G_F\;and\;J_{Ic}$ decreased as the notch depth increased and that $G_F$ was less sensitive than $J_{Ic}$. Therefore, the former, $G_F$, is more appropriate in using it as the concrete fracture toughness parameter. The values of $G_F\;and\;J_{Ic}$ increased when the width of concrete specimens increasing from 75 mm to 150 mm. Thus, the effects of the specimen width should be considered in determining the fracture toughness of concrete.

Evaluation of the Antioxidant Potential of Korean Indigenous Plant Extracts by Free Radical Scavenging Activity

  • Kim, Young-Leem;Min, Hye-Young;Park, Eun-Jung;Lee, Yong-Sup;Jin, Chang-Bae;Lee, Sang-Kook
    • Natural Product Sciences
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    • v.9 no.2
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    • pp.80-82
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    • 2003
  • Since reactive oxygen radicals play an important role in carcinogenesis and other human diseases including neurodegenerative states, antioxidants present in natural products have received considerable attention for alleviation of these disease states. Therefore, in order io identify antioxidants in plant extracts, fifty-seven methanolic extracts derided from indigenous Korean plants were primarily assessed for potential to scavenge stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals. As a result, nine plant extracts were found to exhibit the DPPH free radical scavenging activity in the criteria of $IC_{50}<40\;{\mu}g/ml$. In particular, the extracts of Melioma oldhami $(IC_{50}=0.1\;{\mu}g/ml)$, Myrica rubra $(IC_{50}=16.2\;{\mu}g/ml)$, Sympolocos paniculata $(IC_{50}=23.0\;{\mu}g/ml)$, Carpinus laxiflora $(IC_{50}=25.1\;{\mu}g/ml)$, and Cleyera japonica $(IC_{50}=26.2\;{\mu}g/ml)$ showed a potent radical scavenging activity. Further study for the identification of active compounds from these lead extracts might be warranted.

Sensory and Nutritional Properties of Vegetable Rice Porridge Made with Israeli Carp Cyprinus carpio (향어(Cyprinus carpio) 야채죽의 관능 및 영양 특성)

  • Sang In Kang;Ye Youl Kim;Jin-Soo Kim
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.56 no.4
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    • pp.484-493
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    • 2023
  • This study was conducted to investigate the sensory and nutritional properties of vegetable rice porridge made with Israeli carp (VRP-IC), and to compare it with commercial vegetable rice porridges (controls). The proximate composition of VRP-IC per 100 g was 82.4 g moisture, 3.9 g protein, 2.6 g lipids, and 0.9 g ash, and had a lower moisture content than that of the controls, but a higher crude protein, crude lipid, and ash content. In terms of taste, VRP-IC was higher in umami and sourness, but lower in saltiness, sweetness, and bitterness. The viscosity and hardness of VRP-IC were 13,117 mPa·s and 2,258 N/m2, respectively. The total amino acid content of VRP-IC was 3,537.2 mg/100 g, with the maor amino acids being aspartic acid and glutamic acid. The mineral contents of VRP-IC per 100 g were as follows: 114 mg calcium, 70.3 mg phosphorus, 79.1 mg potassium, and 0.23 mg iron. These were all higher than those of the controls. The major fatty acids of VRP-IC were 16:0, 18:1n-9, and 18:2n-6, which were identical to those of the controls. The digestibility of VRP-IC was 86.4%, which was similar to those of the controls.

Characterization of Antioxidants Extracted from Leaves of Sanjook(Sasa boreails var. chiisanensis) (산죽잎으로 부터 추출한 항산화물질의 특성)

  • Yoo Mi-Young;Park Sung-Hee;Kang Young-Mo;Yang Ji-Young
    • Journal of Life Science
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    • v.15 no.5 s.72
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    • pp.796-801
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    • 2005
  • For usage of natural antioxidants, sanjook (Sasa boreails var. chiisanensis) leaves were extracted with methanol and investigated about its antioxidative activities and stability. It showed that the antioxidant activity of methanol extracts from the leaves of sanjook depend on their concentration within range of 0.1 to 0.8 mg/ml. The methanol extracts from the leaves of sanjook represented $583{\mu}g/ml$ for $IC_{50}$ of DPPH radical scavenging ability, $800{\mu}g/ml$for $IC_{50}$ of SOD-like activity and $38{\mu}g/ml$for $IC_{50}$ of $H_{2} O_{2}$ scavenging ability, while BHT, as a compared substance, was $271{\mu}g/ml$ for $IC_{50}$ of DPPH radical scavenging ability, $680{\mu}g/ml$ for $IC_{50}$ of SOD-like activity and $30{\mu}g/ml$ for $IC_{50}$ of $H_{2} O_{2}$ scavenging ability, respectively. The anti-au-toxidation effect for methanol extracts from the leaves of sajook was $55\∼60\%$ within range of 0.1 to 0.8 mg/ml. The pH stability on methanol extracts from the leaves of sanjook was most stable at pH 6. The more acid or akali it became, the more unstable it turned. The thermostability on methanol extracts from the leaves of sanjook remained above $80\%$ of their DPPH activity at range of $0^{\circ}C{\;}to{\;}120^{\circ}$.

Effects of Natural Products on the Inhibition of Lipopolysaccharide-Inducible Nitric Oxide Synthase Activity in RAW264.7 Cell Culture System

  • Park, Bong-Joo;Cho, Myung-Haing;Kim, Kyeong-Ho;Lee, Sang-Kook;Lee, Chong-Soon;An, Gil-Hwan;Mar, Woong-Chon
    • Natural Product Sciences
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    • v.5 no.3
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    • pp.113-120
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    • 1999
  • Nitric oxide (NO) is a free radical synthesized from L-arginine by nitric oxide synthase (NOS). It is believed that NO is an important mediator in numerous physiological and inflammatory responses. Particularly, a large amount of NO released from the inducible nitric oxide synthase (iNOS) is mostly associated with inflammatory processes. Overproduction of NO in these processes including sepsis and autoimmune diseases can have deleterious consequences and pathophysiologic relevance. Therefore, for the discovery of new inhibitory agents against iNOS activity, we have evaluated about 100 kinds of natural products after partition into three layers (n-hexane, ethyl acetate and aqueous) from 100% methanol extracts to study inhibitory effects on iNOS activity induced by lipopolysaccharide (LPS) in RAW264.7 cells culture system. As a positive control, curcumin, which is known as an anti-tumor promoter, anti-inflammatory agent as an iNOS inhibitor, was used and showed the dose-dependent inhibitory effect $(IC_{50},\;2.5\;{\mu}g/ml)$. Among tested fractions, the n-hexane fraction of Cimicifuga heracleifolia $(IC_{50}:\;9.65\;{\mu}g/ml)$, Forsythiae fructus $(IC_{50}:\;6.36\;{\mu}g/ml)$, Saposhnikovia divaricata $(IC_{50}:\;5.92\;{\mu}g/ml)$, and the ethyl acetate fraction of Chrysanthemum sibiricum $(IC_{50}:\;2.56\;{\mu}g/ml)$, Gastrodia elata $(IC_{50}:\;3.46\;{\mu}g/ml)$, and the aqueous fraction of Dianthus chinensis $(IC_{50}:\;6.73\;{\mu}g/ml)$, Euonymus alatus $(IC_{50}:\;6.78\;{\mu}g/ml)$, Mechania urticifoloria $(IC_{50}:\;8.01\;{\mu}g/ml)$ showed strong inhibitory activity against LPS-stimulated iNOS. Especially, the ethyl acetate fraction of Chrysanthemum sibiricum $(IC_{50}:\;2.56\;{\mu}g/ml)$, which exhibited the strongest inhibition against iNOS, was fractionated with silica-gel column chromatography. These subfractions exhibited dose-dependent inhibition against iNOS activity in the range of $2.59-5.6\;{\mu}g/ml$ except for fraction No. 3, 4, 5, 6, 8, 9, and 16. Our study shows that Chrysanthemum sibiricum has the strongest inhibitory effect against iNOS activity and has similar effect to curcumin. Therefore, further studies for the identification of active principles from Chrysanthemum sibiricum and investigation for the mechanism of the inhibition of iNOS by active principles will be performed.

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

  • Joo, Shin Youn
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.4
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    • pp.512-519
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    • 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.

Anti-melanogenesis Effect of Phenolic Compounds Isolated from Gastrodia elata (천마(Gastrodia elate) 추출물로부터 분리된 페놀성 물질의 멜라닌 생성 억제작용)

  • 김경태;김진국;박선희;이정하;이수희;김기호;박수남
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.1
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    • pp.33-38
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    • 2004
  • Melanin pigmentation in human skin is a major defense mechanism against ultraviolet light of the sun, but abnormal pigmentation such as freckles, liver spot could be a serious aesthetic problem. Nearly all studies are mainly concentrated on searching for the materials that have inhibitory activities on tyrosinase. In this work, to isolate phenolic compounds from Gastrodia elata, we purified the extract through solvent fractionation, column chromatography, and recrystallization. They were identified as 4-hydroxybenzyl alcohol 1, bis(4-hydroxyphenyl)methane 2, gastrodin (4-${\beta}$-D-glucopyranosyloxybenzyl alcohol) 3 on the base of spectroscopic evidences. In order to investigate their depigmentation effect, inhibitory activity against mushroom tyrosinase and inhibitory activity of melanin synthesis in B16 melanoma cells were evaluated in vitro. We have found that 4-hydroxybenzyl alcohol 1 and gastrodin (4- ${\beta}$-D-glucopyranosyloxybenzyl alcohol) 3 have no tyrosinase inhibitory activity, but inhibit the melanin synthesis in B16 melanoma cells. Tyrosinase inhibitory activities of bis(4-hydroxyphenyl)methane 2 (IC$\_$50/ = 400 $\mu\textrm{g}$/mL) and butanol fraction (IC$\_$50/ = 46 $\mu\textrm{g}$/mL) were lower/higher than that of arbutin (IC$\_$50/ = 114 $\mu\textrm{g}$/mL), but inhibitory activities of melanin synthesis in B16 melanoma cells were much higher than that of arbutin. Especially, tyrosinase inhibitory activities of isolated phenolic fraction (IC$\_$50/ = 2.37 $\mu\textrm{g}$/mL) from butanol fraction was very higher than that of arbutin (IC$\_$50/ = 114 $\mu\textrm{g}$/mL). Therefore, these results suggest that isolated phenolic compounds from Gastrodia elata have inhibitory activity against mushroom tyrosinase and inhibitory activity of melanin synthesis in 816 melanoma cells in vitro.

Study on the Anti-oxidative, Anti-microbial and Anti-cancer effect of Bibangtalmyungsan. (비방탈명산(秘方奪命散)의 항산화 ${\cdot}$ 항암 ${\cdot}$ 항균 효과 연구)

  • Han, Hong-Jun;Choi, Jeong-Hwa;Park, Su-Yeon;Kim, Jong-Han
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.20 no.1 s.32
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    • pp.115-129
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    • 2007
  • Objectives : This study was carried out to evaluate anti-oxidative, anti-microbial and anti-cancer effect for clinical application of Bibangtalmyungsan (BTS) Results : 1. The oxidative effects were measured by polyphenol, DPPH radical scavenging activity. BTS water extract was showed more effective than ethanol extract and also various solvent fractions from BTS water extract showed effective in the following order : ethyl acetate fraction > butanol fraction > hexane fraction ${\fallingdotseq}$ chloroform fraction ${\fallingdotseq}$ aqueous fraction 2. The results of anti-microbial effects were as follows. 1) Antibacterial activities of BTS extracts against Gram's negative and positive bacteria were ineffective 2) Antifungal activities of the BTS extracts against Aspergillus spp. , Trichohyton mentagrophyte KTCC 1077 were not effective. 3. The result of anti-cancer effects were as followings: 1) BTS ethanol extract was more effective than water extract against Caco-2, Calu-6, but it had cytotoxic effect against NIH3T3. 2) On the Caco-2, effective only in ethyl acetate $fraction(IC_{50}:$ 35.81 ${\mu}g/ml)$. 3) On the Calu-6, the most effective in ethyl acetate $fraction(IC_{50}:$ 189.65 ${\mu}g/ml)$ and effective In butanol $fraction(IC_{50}:$ 299.74 ${\mu}g/ml)$ and hexane $fraction(IC_{50}:$ 345.13 ${\mu}g/ml)$ 4) On the SUN-601, $IC_{50}$ value was within 80 ${\mu}g/ml$ in ethyl acetate fraction and hexane fraction. 5) On the HCT-1l6, the most effective in ethyl acetate $fraction(IC_{50}:$ 82.94 ${\mu}g/ml)$ and effective in hexane $fraction(IC_{50}:$ 374.56 ${\mu}g/ml)$. 6) On the AML-2/WT, the most effective in ethyl acetate $fraction(IC_{50}:$ 41.44 ${\mu}g/ml)$ and effective In hexane $fraction(IC_{50}:$ 303.01 ${\mu}g/ml)$. 7) On the NIH3T3, effective only in ethyl acetate $fraction(IC_{50}:$ 203.42 ${\mu}g/ml)$, but it was more ineffective than other cancer cells. Conclusion : These result suggest that BTS has antioxidative, antifungal activities and cytotoxic effects against Caco-2, Calu-6, SUN-601, HCT-116, AML-2/WT and NIH3T3, especially ethyl acetate fraction from water extract has more effective in antioxidative and anticancer effects.

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