• Title/Summary/Keyword: active agents

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Inhibition of Topoisomerase-mediated DNA Cleavage by Lycoperdon perlatum (말불버섯 추출물의 Topoisomerase 저해 효과)

  • Park, Mi-Jung;Cho, Kang-Jin;Kim, Jung-Bong;Kim, Dong-Hern;Kim, Yang-Sub;Seok, Soon-Ja;Kim, Sun-Yeou;Hwang, Young-Soo
    • Korean Journal of Food Science and Technology
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    • v.29 no.5
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    • pp.1057-1062
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    • 1997
  • In the course of searching for anticancer agents from 32 mushrooms, it was found that methanol extract of Lycoperdon perlatum showed inhibitory effect on topoisomerase II-mediated DNA cleavage. This active methanol extract was sequentially fractionated with hexane, chloroform, n-buthanol and water. Among the solvent-fractionated extracts, $1\;{\mu}g/mL$ hexane fraction of L. perlatum inhibited on topoisomerase II-mediated DNA cleavage. The effect of hexane fraction of L. perlatum was dose- and reaction time-dependent. The hexane fraction of L. perlatum was found to have inhibitory activity on relaxation assay of DNA topoisomerase I. The hexane fraction of cultured L. perlatum, however, had no inhibitory effect on either type of topoisomerase.

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Isolation of Sesquiterpene Synthase Homolog from Panax ginseng C.A. Meyer

  • Khorolragchaa, Altanzul;Parvin, Shohana;Shim, Ju-Sun;Kim, Yu-Jin;Lee, Ok-Ran;In, Jun-Gyo;Kim, Yeon-Ju;Kim, Se-Young;Yang, Deok-Chun
    • Journal of Ginseng Research
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    • v.34 no.1
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    • pp.17-22
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    • 2010
  • Sesquiterpenes are found naturally in plants and insects as defensive agents or pheromones. They are produced in the cytosolic acetate/mevalonate pathway for isoprenoid biosynthesis. The inducible sesquiterpene synthases (STS), which are responsible for the transformation of the precursor farnesyl diphosphate, appear to generate very few olefinic products that are converted to biologically active metabolites. In this study, we isolated the STS gene from Panax ginseng C.A. Meyer, designated PgSTS, and investigated the correlation between its expression and various abiotic stresses using real-time PCR. PgSTS cDNA was observed to be 1,883 nucleotides long with an open reading frame of 1,707 bp, encoding a protein of 568 amino acids. The molecular mass of the mature protein was determined to be 65.5 kDa, with a predicted isoelectric point of 5.98. A GenBank BlastX search revealed the deduced amino acid sequence of PgSTS to be homologous to STS from other plants, with the highest similarity to an STS from Lycopersicon hirsutum (55% identity, 51% similarity). Real-time PCR analysis showed that different abiotic stresses triggered significant induction of PgSTS expression at different time points.

Analysis of epidemiological change of hair colored Acer palmatum Leaves extract as hair treatment product (헤어 트리트먼트제로서 단풍잎 추출물 컬러링 모발의 역학적 변화분석)

  • Park, Jang-Soon
    • Journal of Digital Convergence
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    • v.18 no.8
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    • pp.479-484
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    • 2020
  • In the social atmosphere where the importance of appearance is increasing day by day, efforts and desires of modern people are becoming more active and diversified, and the beauty beauty industry is gradually becoming more specialized and specialized due to these effects. Hair damage is inevitable due to the excessive permanent wave or hair coloring of modern people. However, as the hair is damaged, the cuticle peels off and falls off, and the tensile force decreases and the satisfaction after hair styling or perm decreases relatively. Therefore, it is necessary to manage damaged hair, but since artificial synthetic products occupy most of hair treatment agents on the market, it is necessary to develop a hair treatment product containing antioxidants useful for the human body. In this study, the effect of maple leaf extract on the mechanical change of colored hair was analyzed to investigate the potential of maple leaf extract as a hair treatment agent to improve damaged hair and improve hair health. It is considered that this study will be used as basic data for the development of hair beauty products using natural products in the future.

Technology on the Shrinkage Reduction of High Performance Concrete (고성능 콘크리트의 수축 저감 기술)

  • Koh, Kyung-Taek;Ryu, Gum-Sung;Kang, Su-Tae;Park, Jung-Jun;Kim, Sung-Wook;Han, Cheon-Goo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.1101-1104
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    • 2008
  • Recently, active researches are conducted on high performance concrete(HPC) exhibiting high strength and high fluidity. These researches are resulting in increased applications on real structures. In order to satisfy the required performances, HPC makes use of large quantities of binder and presents low water-cementitious material ratio. Such mixing is increasing significantly the autogenous shrinkage, which subsequently is likely to favor the potential development of cracks. Therefore, we investigated the effect of used materials and mix proportions on the shrinkage properties of HPC, and of the use of expansive additives and shrinkage reducing agents on the HPC. The autogenous shrinkage of HPC using blast furnace slag are tend to be increased, in some case have the potential development of cracks by only the autogenous shrinkage. Also the using method in combination with expansive additive and shrinkage reducing agent is more effective than the separately using method of that.

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Effects of Wounding and Jasmonic Acid on Polyphenol Oxidase in Tomato Seedlings (토마토 유식물의 Polyphenol Oxidase에 미치는 상해 및 Jasmonic Acid의 영향)

  • Jin Sun-Young;Hong Jung-Hee
    • Journal of Environmental Science International
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    • v.8 no.6
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    • pp.669-676
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    • 1999
  • The effects of wounding and jasmonic acid(JA) on polyphenol oxidase(PPO) in tomato(Lycopersicon esculentum Mill.) seedlings were investigated. PPO was strongly induced by wounding or JA, and the response was also shown to be systemically induced by wounding. Mechanical wounding in cotyledon or leaf produced a signal that caused the concentration of PPO to increase in the unwounded cotyledon, in the first leaves but not in the second leaves. Severity of wounding and light intensity also affected wound induced change in PPO activity, JA showed a stimulatory effect on the loss of chlorophyll and the rapid increase in PPO activity. The PPO was clearly more active in the wounded leaves than in controls. The potency and specificity of the JA indicate a close relationship between JA and wound-induced changes in PPO in tomato species. JA and abscisic acid(ABA) acted similarly on both unwounded and wounded leaves, but the amount of PPO in the wounded leaves was always more than the respective controls. The highest increase in PPO activity occurred in woundand JA-induced leaves of seedlings kept under bright lighting. Benzyladenine(BA) completely abolished JA- and ABA-induced PPO activity. The results suggest that JA-induced PPO activity is due to de novo PPO synthesis. Histochemical tests for PPO in stems of wound- and JA -treated tomato plants indicate that PPO was localized primarily, in the. outer .cortex . and xylem parenchyma. It is concluded that exogenously applied JA acts as stress agents and PPO may be a component of the inducible anti-hervivore defense response.

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An Experimental Study for Effect Organic/Inorganic Hybrid based Durability Promoting Agent(DPA) on the Properites of concrete (유무기 복합형 내구성개선제가 콘크리트 물성에 미치는 효과에 대한 실험적 연구)

  • Kim, Do-Su;Khil, Bae-Su;Kim, Woo-Jae;Kim, Sung-Su;Jeong, Yong;Jung, Sang-Jin
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.801-804
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    • 2008
  • Performance for the resistant to chlorides penetration is required in order to increase durability of seaside construction. For this reason, it is important to acquire simultaneously watertightness, resistance for crack of concrete and chemical fixation effect of chloride in it. In this study, High durability promoting agents(HD) consist of inorganic salt and active components were applied to enhancing resistance for chloride ion penetration against concrete based on mix(composition of binder : OPC+SLG) of seaside construction. Tang's experimental method was utilized to investigate the resistances of chloride ion penetration of concrete such as chloride ion diffusion coefficient and penetration depth. It was confirmed that resistance of chloride ion penetration of concrete by 0.6% addition of HD was improved to $11.3^{\sim}20.5$% than non-added concrete.

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A Design and Implementation of Course Relearning System using Multi-agent (멀티 에이전트를 이용한 코스 반복 학습 시스템의 설계 및 구현)

  • Lee, Jong-Hui;Lee, Geun-Wang
    • The KIPS Transactions:PartB
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    • v.8B no.6
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    • pp.595-600
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    • 2001
  • Recently, WBI model which is based on web has been proposed in the part of the new activity model of teaching-learning. The demand for the customized coursewares which is required from the learners is increased, the needs of the efficient and automated education agents in the web-based instruction are recognized. But many education systems that had been studied recently did not service fluently the courses which learners had been wanting and could not provide the way for the learners to study the learning weakness which is observed in the continuous feedback of the course. In this paper we propose design of multi-agent system for course scheduling of learner-oriented using weakness analysis algorithm. First, proposed system monitors learner's behaviors constantly, evaluates them, and calculates his accomplishment. From this accomplishment, the multi-agent schedules the suitable course for the learner. The learner achieves an active and complete learning from the repeated and suitable course.

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The Inhibitory Effects of Nelumbo nucifera Gaertner Extract on Melanogenesis (연자육 추출물의 멜라닌 합성 저해효과)

  • Lee, Jun Young;Im, Kyung Ran;Jung, Taek Kyu;Yoon, Kyung-Sup
    • KSBB Journal
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    • v.28 no.2
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    • pp.137-145
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    • 2013
  • In order to develop new skin whitening agents, we prepared the $CH_2Cl_2$ layer (NGC) and BuOH layer (NGB) of 75% EtOH extract of the Nelumbinis nucifera Gaertner. We measured their tyrosinase inhibitory activity in vitro and melanin synthesis inhibitory activity in B16-F1 melanoma cells. They did not show inhibitory activity against mushroom tyrosinase but showed melanin synthesis inhibitory activity in a dose-dependent manner. In a melanin synthesis inhibition assay, NGC and NGB suppressed melanin production up to 52% and 46% at a concentration of $100{\mu}g/mL$, respectively. To elucidate the mechanism of the inhibitory effects of NGC and NGB on melanogenesis, we measured the expression of melanogenesis-related proteins by western blot assay. As a result, NGC suppressed the expression of tyrosinase, tyrosinase related protein 1 (TRP-1), tyrosinase related protein 2 (TRP-2), phosphorylated cAMP responsive element binding (p-CREB) protein, and microphthalmia associated transcription factor (MITF). And NGB inhibited the protein expression of tyrosinase and MITF, but had no significant effect on TRP-1, TRP-2, and p-CREB expression. Moreover, NGB increased the expression of phosphorylated extracellular signal-regulated kinase (p-ERK). In addition, we examined the inhibitory effect on the glycosylation of tyrosinase. As a result, NGC and NGB inhibited the activity of ${\alpha}$-glucosidase in vitro and the glycosylation of tyrosinase in B16-F1 melanoma cells. From these results, we concluded that NGC and NGB could be used as active ingredients for skin whitening.

Antiplatelet Effects of Garlic and Chitosan: a Comparative Study between Fermented and Non-Fermented Preparations

  • Irfan, Muhammad;Kim, Minki;Kwon, Hyuk-Woo;Rhee, Man Hee;Kim, Hyun-Kyoung
    • Biomedical Science Letters
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    • v.24 no.3
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    • pp.280-284
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    • 2018
  • The incidence of cardiovascular diseases (CVDs) is increasing rapidly in developed countries, with CVDs now representing the leading cause of morbidity and mortality. Natural products and ethnomedicines have been shown to reduce the risk of CVDs. Garlic is a medicinal plant used throughout the world for its anti-inflammatory, antioxidant, and antiplatelet activities. Chitosan is a natural polysaccharide obtained from chitin, and derivatives of chitosan have been shown to inhibit platelet aggregation and adhesion. We hypothesized that fermented preparations of these products may possess stronger antiplatelet effects than the non-fermented forms owing to the increased bioavailability of the bioactive compounds produced during fermentation. Therefore, we compared these compounds via in vitro and ex vivo platelet aggregation assays by using standard light transmission aggregometry and ex vivo granule secretions from rat platelets. We found that fermented preparations exerted more potent and significant inhibition of platelet aggregation both in vitro and ex vivo. Likewise, ATP release from dense granules of platelets was also significantly inhibited in fermented preparation-treated rat platelets compared to that in non-fermented preparation-treated ones. We concluded that fermented preparations exerted more potent effects on platelet function both in vitro and ex vivo, possibly as a result of the increased bioavailability of active compounds produced during fermentation. We therefore suggest that fermented products may be potent therapeutics against platelet-related CVDs and can be used as antiplatelet and antithrombotic agents.

Identification of a Mature form and Characterization of Thermostability of a Serine-type Protease from Aquifex pyrophilus

  • Kim, Yun-Kyeong;Choi, In-Geol;Nam, Won-Woo;Yu, Yeon-Gyu
    • BMB Reports
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    • v.33 no.6
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    • pp.493-498
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    • 2000
  • Aquifex pyrophilus, a hyperthermophilic bacterium, has a serine-type protease that is located at the cell wall fraction with a mature size of 43 kDa. Molecular cloning of the protease gene revealed that it has an ORF of 619 amino acids with homologous catalytic site of serine-type proteases [Choi, I.-G., Bang, W.-K., Kim, S.-H., Yu, G. Y., J. Biol. Chem. (1999), Vol. 274, pp. 881-888]. Constructs containing different regions of the protease gene, including a alanine-substituted mutant at the active site serine, were constructed, and the factors affecting the expression level of the cloned protease gene in E. coli were examined. The presence of the C-terminus hydrophobic region of the protease hindered over-expression in E. coli. Also, the proteolytic activity of the expressed protein appeared to toxic to E. coli. An inactive form that deleted both of the N-terminal signal sequence and the C-terminal polar residues was over-expressed in a soluble form, purified to homogeneity, and its thermostability examined. The purified protein showed three disulfide bonds and three free sulfhydryl group. The thermal denaturation temperature of the protein was measured around $90^{\circ}C$ using a differential scanning calorimeter and circular dichroism spectrometry. The disulfide bonds were hardly reduced in the presence of reducing agents, suggesting that these disulfide bonds were located inside of the protein surface.

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