• Title/Summary/Keyword: inhibiting

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Character and Function of Restriction Enzyme, EcoRI Inhibiting Substance Extracted from Spinach Chloroplast and Chlamydomonas (시금치 엽록체와 Chlamydomonas로부터 추출한 제한효소 EcoRI 억제물질의 특성과 작용)

  • 황성빈
    • Journal of Plant Biology
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    • v.33 no.4
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    • pp.217-223
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    • 1990
  • Restriction enzyme inhibiting substance (REIS) extracted from spinach chloroplast and Chlamydomonas seems not to be proteinaceous, because its inhibiting activity was not lost by heat or trypsin treatment. And it seems not to be lipid or polysacchride, because its inhibiting activity was not lost by lipase or $\alpha$-amylase treatment, respectively. In Chlamydomonas, putrescine, spermidine and spermine were present. The amount of putrescine was the smallest and that of spermie was the greatest. But only spermine was contained in REIS and the activity of REIS. It was proportional to the amount of spermine in REIS and it was hindered by Na+ ion. So, the inhibiting activity of REIS seems to be deeply related to spermine contained in REIS. But restriction enzyme inhibiting activity remained to the some extent although salts and spermine were eliminated by dialysis.

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Tyrosinase-Inhibiting Isoflavonoids Produced by Streptomyces sp. 20747 (Streptomyces sp. 20747이 생산하는 Tyrosinase-Inhibiting Isoflavonoids)

  • 이충환;전효곤;고영희;서영배
    • Microbiology and Biotechnology Letters
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    • v.21 no.2
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    • pp.139-143
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    • 1993
  • Three isoflavonoids having tyrosinase-inhibiting activity were isolated from the culture filtrate of Streptomyces sp. 20747. Their structures were determined by UV, EI-MS, 1H-NMR, 13C-NMR to be daidzein, daidzein 7-rhamnoside, and genistein 7-rhamnoside, which were competitive with substrate and had IC50 value of 14, 19, and 16 ng/ml, respectively to mushroom tyrosinase and did not inhibit melanin production of Streptomyces bikiniensis. Soybean meal as well as peptone were found to be a good nitrogen source for tyrosinase-inhibiting isoflavonoids production, susgesting that soybean meal is not the origin of tyrosinase inhibiting isoflavonoids formation in Streptomyces sp. 20747 strain.

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Characterization of an Apple Polygalacturonase-Inhibiting Protein (PGIP) That Specifically Inhibits an Endopolygalacturonase (PG) Purified from Apple Fruits Infected with Botryosphaeria dothidea

  • Lee Dong-Hoon;Bae Han-Hong;Kang In-Kyu;Byun Jae-Kyun;Kang Sang-Gu
    • Journal of Microbiology and Biotechnology
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    • v.16 no.8
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    • pp.1192-1200
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    • 2006
  • An apple polygalacturonase-inhibiting protein (PGIP), which specifically inhibits endopolygalacturonase (PG, EC 3.2.1.15) from Botryosphaeria dothidea, was purified from Botryosphaeria dothidea-infected apple (Malus domestica cv. Fuji) fruits. The purified apple PGIP had a molecular mass of 40 kDa. The N-terminal amino acid sequence of the purified protein showed high homologies to those of PGIP from pear (100%), tomato (70%), and bean (65%). We also purified polygalacturonase (PG) from B. dothidea. The PG hydrolyzes pectic components of plant cell walls. When the extracted apple pectic cell wall material was treated with purified apple PGIP and B. dothidea PG, the amount of uronic acid released was lower than that treated with B. dothidea PG alone. This result demonstrates that PGIP functions specifically by inhibiting cell wall maceration of B. dothidea PG Furthermore, we characterized the de novo function of the PGIP against PG on the solubilization and depolymerization of polyuronides from cell wall of apple fruits inoculated with B. dothidea. This result demonstrated that the PGIP of plants exhibits one of the direct defense mechanisms against pathogen attack by inhibiting PGs that are released from pathogens for hydrolysis of cell wall components of plants.

Study on the Anti-Cancer Effect of Acanthopanax Sessiliflorus (오가피(五加皮)의 항암효과에 관한 연구)

  • Kim, Young-Chul;Woo, Hong-Jung;Lee, Jang-Hoon
    • The Journal of Korean Medicine
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    • v.20 no.3 s.39
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    • pp.54-65
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    • 1999
  • Objectives: Hepatoma is a very serious disease in Korea and vvorldwiclc. Hepatitis B vims (HBV) has proved the most significant cause of hepatoma. We canied out this study to investigate the effect of Acanthopanax sessilifloms on inhibiting cell proliferation and DNA synthesis in HepG2.2.15 cell line and on inhibiting phosphorilation of oncogene (MAP kinase) in NIT/3T3-HBx ceIl. Methods: To investigate the anti-cancer effect of Acanthopanax sessiliflorus, we did the CellTiter 96 Aqueous Non-radioactive Cell Proliferation assay (Promega); MTS/PMS assay, [$^3H$]-thymicline incorporation assay, and we measured the gene expression through westem blotting. Results: Acanthopanax sessiliflorus showed an inhibiting effect on the increase of HepG2.2.15 in the NTS/PMS assay. It also showed an inhibiting effect on DNA synthesis of HepG2.2.15 in the [$^3H$]-thymidine incorporation assay. Acanthopanax sessiliflorus showed an inhibiting effect of phosphorilation of MAP kinase in HBV - X genes. too. Conclusions: The results suggested that this herb had an anti cancer effect. We may discover an effective anti-cancer herb medicine through further studies on this herb medicine.

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Promoting and Inhibiting Factors on Information Sharing between Buyers and Sellers (유통경로 내 구매자와 판매자 간 정보공유의 촉진요인과 억제요인)

  • Kim, Sang-Deok
    • Knowledge Management Research
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    • v.10 no.2
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    • pp.1-14
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    • 2009
  • This study has investigated the effects of promoting and inhibiting factors on information sharing between buyers and sellers in Korean distribution industry. Based on intensive literature reviews, eight promoting factors(satisfaction, relational norms, trust, commitment, fairness, formalization, participation, transaction specific investment) and five inhibiting factors(opportunism, environmental uncertainty, conflict, concentration, monitoring) were included in the research model. For the purpose of empirical testing, 320 respondents of retailers in Korea were surveyed and the analysis utilizing structural equation model indicated that satisfaction, relational norms, trust, commitment, fairness, formalization, and participation had positive effects on information sharing. And concentration and monitoring had negative effects on it. However transaction specific investment, opportunism, conflict, and environmental uncertainty had no significant effects.

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Anti-Apoptosis Engineering Using a Gene of Bombyx mori

  • Kim, Eun-Jeong;Park, Tae-Hyeon
    • 한국생물공학회:학술대회논문집
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    • 2002.04a
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    • pp.62-65
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    • 2002
  • We have previously shown that the addition of silkworm hemolymph to a culture medium increases the longevity of insect and mammalian cells by inhibiting apoptosis. This indicates that the component which inhibits apoptosis is contained in the silkworm hemolymph, The apoptosis-inhibiting component was isolated from silkwonn hemolymph and characterized in our previous study. A database search using the N-terminal amino acid sequence of this component as a template resulted in a 95% homology with a low molecular weight lipoprotein, the so called ’30K protein' of unknown function. In this study, the 30K protein gene was expressed in mammalian and insect cells to confirm the apoptosis-inhibiting effect. The overexpression of 30K protein in mammalian cell inhibited the staurosporin-induced apoptosis by the prevention of the activation of caspase 3. Using an Autographa californicanuclear polyhedrosis virus (AcNPV) system, the 30K protein was overexpressed also in insect cells. The expression of the 30K protein increased the longevity of baculovirus-infected insect cells by inhibiting apoptosis. These results suggest that the 30K protein is a novel anti-apoptotic protein.

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How Do the Prefrontal Lobes Mediate Scientific Reasoning and Conceptual Change in Adolescents ? (청소년들에게서 전두엽연합령은 어떻게 과학적 추론 및 과학개념 변화의 수행을 매개하는가?)

  • Kwon, Yong-Ju
    • Journal of The Korean Association For Science Education
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    • v.18 no.3
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    • pp.427-441
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    • 1998
  • The present study tested the hypothesis that adolescents' performance on scientific reasoning tasks and their ability to change theoretical concepts during instruction are mediated by prefrontal-cognitive functions, such as planning and inhibiting. Subjects sampled from four Korean secondary schools were administered a test of scientific reasoning ability and tests of the prefrontal lobe functions. A series of lessons on theoretical concepts was also administered. Subjects' performance on the test of scientific reasoning and pre- to posttest gains in the concept test were used as dependent variables. This study found that students' planning and inhibiting abilities were highly correlated with and they significantly predicted their scientific reasoning ability and conceptual gains. Further, principal component analysis showed prefrontal lobe functions were categorized into two main components. Component 1, which was loaded by planning and working memory functions, was termed as the representing process. Component 2, which was loaded primarily by the inhibiting functions, was termed as the inhibiting process. Scientific reasoning and conceptual change were also linked to these two components, indicating that these cognitive processes are mediated by both representing and inhibiting processes.

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Inhibiting Activity of Garlic on a Drug Metabolizing Enzyme CYP3A4 (마늘의 약물대사효소 CYP3A4 저해 활성)

  • Lee, Eun-Hee;Cha, Bae-Cheon
    • Korean Journal of Pharmacognosy
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    • v.37 no.2 s.145
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    • pp.97-102
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    • 2006
  • Garlic(Allium sativum Linn) is widely used as a common condiment for a variety of foods and beverages. It has been well known that fresh garlic and garlic supplement of commercial preparations have various therapeutic properties including antimicrobial activity, antiplatelet aggregation, antihypertension, and cholesterol-lowering effects, which contribute to its increasing uses for an alternative medicine. Allicin(diallyl thiosulfinate), the major bioactive components of garlic, is formed by alliinase cleavage of the naturally occurring alliin upon crushing or mincing of garlic, and is the progenitor of a number of other products, such as diallyl disulfide. CYP3A4, heme-containing monooxygenase, is a key enzyme responsible for drug metabolism. Therefor, in the present study, we isolated and examined the compounds with CYP3A4-inhibiting activities from garlic. Among EtOAc extracts of garlic, we found that N-p-coumaroyltyramine and N-feruloyltyramine showed remarkable CYP3A4-inhibiting activities, compared to diallyl disulfide. Structures of the isolated active compounds were established by chemical and spectroscopic means.

Investigation of the Possibility of Applying Protection Motivation Theory in Consumers' Changes by Fipronil Egg Contamination (살충제 달걀 파동에 대한 소비자의 행동변화에서 보호동기이론의 적용 가능성 검토)

  • Youn, Hyun-Ju;Lee, Ji-Hye
    • Journal of the Korean Dietetic Association
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    • v.26 no.4
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    • pp.278-288
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    • 2020
  • This study examined the effects of response-facilitating factors(Food-related Knowledge, Response-Efficacy, and Self-Efficacy) and response-inhibiting factors(Severity, Vulnerability, and Consumer Stress) on the consumer' behavior intention based on protection motivation theory, which explains the behavioral change to protect oneself. This study was conducted to reduce the customers' concerns regarding food safety accidents and introduce ways to make them more interested in food safety. A sample of 225 adults over 19 years of age was collected in February 2018 through a self-administered questionnaire. The results of the cognitive mediation process of protective motivation theory showed that the consumers' knowledge and self-efficacy which are response-facilitating factors, positively influence the behavioral intention. Severity and consumer stress were response-inhibiting factors. On the other hand, response-efficacy, which is a response-facilitating factor, and vulnerability, which is a response-inhibiting factor, did not influence the behavioral intention. Therefore, severity and consumer stress are response-inhibiting factors. The results were analyzed as a result of a behavioral change to protect oneself from food safety accidents. The applicability of the theory of protection motivation on the topic of food safety was also confirmed.

Antibacterial Activity of Pinus densiflora Leaf-Derived Components Toward Human Intestinal Bacteria

  • Hwang, Young-Hee;Lee, Hoi-Seon
    • Journal of Microbiology and Biotechnology
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    • v.12 no.4
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    • pp.610-616
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    • 2002
  • The growth-inhibiting effects of Pinus densiflpora leaf-derived materials on nine human intestinal bacteria were investigated using the impregnated paper disk method, and their activities were compared with those of 13 commercially available terpenes. The biologically active constituent of the extract of P densiflora leaf was characterized as the monoterpene (1R)-(+)-$\alpha$-pinene by various spectroscopic analyses. Responses varied according to bacterial strain, chemicals, and dose. At 10 mg/disk, limonene and (1R)-(+)-$\alpha$-pinene strongly inhibited the growth of Clostridium perfringens, Staphylococcus aureus, and Escherichia coli, without adverse effects on the growth of five lactic acid-bacteria (Bifidobacterium adolescentis, B. bifidum, B. longum, Lactobacillus acidophilus, and L. casei). Little or no inhibition against seven bacteria was observed with anethole, borneol, camphor, caryophyllene, 1,8-cineole, estragole, linalool, and $\alpha$-terpineol. Structure-activity relationship revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S-(-)-$\alpha$-, and (1S-(-)-$\beta$-pinenes. Furthermore, the growth-inhibition against L. casei was much more pronounced in (1R)-(+)-$\beta$- and (In-(-)-$\beta$-pinenes than (1R)-(+)-$\alpha$- and (1S)-(-)-$\alpha$-pinenes. These results indicate that the (+)-$\alpha$ form seems to be required against C. perfringens and $\beta$ form against L. casei for growth-inhibiting activity. Morphologically, most strains of C. perfringens were damaged and disappeared at 5 and 2 mg/disk of (1R)-(+)-$\alpha$-pinene. Morphological study revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S)-(-)-$\alpha$-, and (1S)-(-)-$\beta$-pinenes. As naturally occurring growth-inhibiting agents, the Pinus leaf-derived materials described above could be useful preventive agents against diseases caused by harmful intestinal bacteria such as clostridia.