• Title/Summary/Keyword: 탐색적연구

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Investigation on Antioxidant Activity in Plant resources (식물자원의 항산화활성 탐색)

  • Lee, Seung-Eun;Sung, Jung-Sook;Jang, In-Bok;Kim, Geum-Sook;Ahn, Tae-Jin;Han, Hee-Sun;Kim, Ji-Eun;Kim, Young-Ock;Park, Chung-Berm;Cha, Sun-Woo;Ahn, Young-Sup;Park, Ho-Ki;Bang, Jin-Ki;Seong, Nak-Sul
    • Korean Journal of Medicinal Crop Science
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    • v.16 no.5
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    • pp.356-370
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    • 2008
  • This study was conducted for screening on antioxidant activity of 429 plants and selecting new potential antioxidant candidates. In vitro test models such as scavenging activity on DPPH radical and inhibitory activity on linoleic acid oxidation were used in the preliminary study. Flower of Sanguisorba officinalis, flower of Sedum kamtschaticum, flower of Rumex obtusifolius, and root of Sedum kamtschaticum showed very effective antioxidant activity on DPPH radical and linoleic acid oxidation. Those plants showed 8.1, 9.4, 9.9, $11{\mu}g/ml$ in DPPH radical scavenging activity as $SC_{50}$ and did 80.4, 80.1, 84.5, 88.0% in inhibition activity on linoleic acid oxidation, respectively. Root of Sedum middendorfianum M. showed positive effects in superoxide radical scavenging activity ($38.4{\mu}g/ml$) and inhibitory effect on $CuSO_4$-induced LDL oxidation (53.8% at final concentration of $1{\mu}g/ml$). Gleditsia japonica Mig. showed high antioxidant activity on LDL oxidation as 71.6% at final concentration of $1{\mu}g/ml$ and total phenol content of 958.5 mg% as tannic acid equivalent. In conclusion, we think that these plants having potent antioxidant activity might be studied further and could be used as new resources for many purposes including healthy food, functional cosmetics and drug development etc.

Relationships among Brand Equity Components: An Exploratory Study of the Moderating Role of Product Type (품패자산조성부분간적상호관계(品牌资产组成部分间的相互关系): 관우산품충류조절작용적탐색연구(关于产品种类调节作用的探索研究))

  • Moon, Byeong-Joon;Park, Won-Kyu;Choi, Sang-Chul
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.1
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    • pp.98-109
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    • 2010
  • Research on the construction, measurement, and management of brand equity has been extensive since David A. Aaker(1991) and Kevin Lane Keller(1993) first advanced the concept. Recently, much attention has been devoted to the components of brand equity: brand awareness, perceived quality, brand image, and brand loyalty. This study explores the relationships among these components, focusing particularly on the moderating role of product type (utilitarian vs. hedonic) in their causal relationships. A model to study the relationship among components of brand equity, particularly the moderating role of product type, is featured in Figure 1. The hypotheses of the study are proposed as follows: that consumers' brand awareness has a positive influence on brand loyalty and brand image; that consumers' perceived quality has a positive influence on brand loyalty and brand image; that consumers' brand image influences brand loyalty positively; and that relationships among components of brand equity will be moderated by product type. That is, in the case of utilitarian products, the impact of perceived quality on brand loyalty will be relatively stronger, whereas with hedonic products the impact of brand image on brand loyalty will be relatively stronger. To determine the products for the study, a pre-test of 58 college students in the Seoul metropolitan area was conducted based on the product type scale. As a result, computers were selected as the utilitarian product and blue jeans became the hedonic product. For each product type, two brands were selected: Samsung and HP for computers, and Levis and Nix for blue jeans. In the main study, 237 college students in the metropolitan area were surveyed to measure their brand awareness, perceived quality, brand image, and brand loyalty toward the selected two brands of each product type. The subjects were divided into two groups: one group (121 subjects) for computers, the other (116 subjects) for blue jeans. The survey questionnaires for the study included four parts: five questions on brand awareness and four questions each on perceived quality, brand image, and brand loyalty. All questions were to be answered using 7-point Likert scales. The data collected by the survey were processed to assess reliability and validity, and the causal relationships were analyzed to verify the hypotheses using the AMOS 7 program, a tool for analyzing structural equation modeling. A confirmatory factor analysis assessed the appropriateness of the measurement model, and the fit indices denoted that the model was satisfactory. The relationships among the components of brand equity were also analyzed using AMOS 7. The fit indices of the structural model denoted that it was also satisfactory. The paths in the structural model as will be seen in Figure 2 show that perceived quality affects brand image positively, but that brand awareness does not affect brand image. Moreover, it shows that brand awareness, perceived quality, and brand image are positively related with brand loyalty, and that this relationship is moderated by product type. In the case of utilitarian products, perceived quality has relatively more influence on brand loyalty. Conversely, in the case of hedonic products, brand image has relatively more influence on brand loyalty. The results of this empirical study contribute toward the advancement of our understanding of the relationships among the components of brand equity and expand the theoretical underpinnings for brand equity measurement. It also helps further our understanding of the effect of product type on customer-based brand equity. In a marketing management practice perspective, these results may provide managerial implications for building and maintaining brand equity effectively.

Effects of Lipopolysaccride-induced Stressor on the Expression of Stress-related Genes in Two Breeds of Chickens (Lipopolysaccride 감염처리가 닭의 품종간 스트레스연관 유전자 발현에 미치는 영향)

  • Jang, In Surk;Sohn, Sea Hwan;Moon, Yang Soo
    • Korean Journal of Poultry Science
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    • v.44 no.1
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    • pp.1-9
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    • 2017
  • The objective of the present study was to determine the expression of genes associated with lipopolysaccharide (LPS)-induced stressor in two breeds of chickens: the Korean native chicken (KNC) and the White Leghorn chicken (WLH). Forty chickens per breed, aged 40 weeks, were randomly allotted to the control (CON, administered the saline vehicle) and LPS-injected stress groups. Samples were collected at 0 and 48 h post-LPS injection, and total RNA was extracted from the chicken livers for RNA microarray and quantitative real-time polymerase chain reaction (qRT-PCR) analyses. In response to LPS, 1,044 and 1,193 genes were upregulated, and 1,000 and 1,072 genes were downregulated in the KNC and WLH, respectively, using a ${\geq}2$-fold cutoff change. A functional network analysis revealed that stress-related genes were downregulated in both KNC and WLH after LPS infection. The results obtained from the qRT-PCR analysis of mRNA expression of heat shock 90 (HSP90), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), activating transcription factor 4 (ATF4), sterol regulatory element-binding protein 1 (SREBP1), and X-box binding protein 1 (XBP1) were confirmed by the results of the microarray analysis. There was a significant difference in the expression of stress-associated genes between the control and LPS-injected KNC and WLH groups. The qRT-PCR analysis revealed that the stress-related $HSP90{\alpha}$ and HMGCR genes were downregulated in both LPS-injected KNC and WLH groups. However, the HSP70 and $HSP90{\beta}$ genes were upregulated only in the LPS-injected KNC group. The results suggest that the mRNA expression of stress-related genes is differentially affected by LPS stimulation, and some of the responses varied with the chicken breed. A better understanding of the LPS-induced infective stressors in chicken using the qRT-PCR and RNA microarray analyses may contribute to improving animal welfare and husbandry practices.

A Study on DNA Polymorphism of the Bovine c-KIT Receptor Gene (소 c-KIT Receptor 유전자의 다형성에 관한 연구)

  • Jang, Y.S.;Kim, T.H.;Yoon, D.H.;Park, E.W.;Lee, H.W.;Lee, H.K.;Cheong, I.C.
    • Journal of Animal Science and Technology
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    • v.44 no.6
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    • pp.653-660
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    • 2002
  • We considered KIT gene as a candidate gene for the white-spotting pattern in cattle. This study was carried out to detect genetic variation of c-KIT receptor gene and to investigate association between the mutation and the white-spotting pattern in cattle. PCR-RFLP analysis within intron 6 of c-KIT receptor gene were performed with 8 cattle breeds including Hanwoo, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin and Simmental. When PCR product of approximately 2,440 bp including intron 6 of c-KIT receptor gene was sequenced, four nucleotide substitutions were found within intron 6 of the bovine c-KIT receptor gene. In PCR-RFLP analysis, three alleles (A, B and C), two alleles (A and B) and two alleles (A and B) at each locus were identified by MspⅠ, BsrBⅠ and NdeⅠ, respectively. Although frequencies of allele at each locus were different among cattle breeds, we could not get any evidence related with white or white spotting phenotypes in these mutations on intron 6 of c-KIT receptor gene. However, we can not entirely exclude the possibility that c-KIT receptor gene is responsible for white spotting phenotype in cattle. Thus, further studies need to detect other mutations in c-KIT receptor gene and to test association of those mutations and coat color phenotypes in cattle.

Understanding Spatial Variations of Water Quality Using Agricultural Nutrient Indices in Chonnam Province (전남 지역 농업분야 양분 지표를 이용한 수질 공간 변이 해석)

  • Jeon, Byeong-Jun;Lim, Sang-Sun;Lee, Kwang-Seung;Lee, Se-In;Ham, Jong-Hyun;Yoo, Sun-Ho;Yoon, Kwang-Sik;Choi, Woo-Jung
    • Korean Journal of Environmental Agriculture
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    • v.33 no.1
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    • pp.44-51
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    • 2014
  • BACKGROUND: Water quality of rural areas are susceptible to agricultural nutrient input and supply such as chemical fertilizer and livestock manure. This study was conducted to evaluate the usefulness of nutrient (N and P) indices in understanding spatial variations of water quality across Chonnam province which is a typical agricultural region in Korea. METHODS AND RESULTS: The nutrient indices including chemical fertilizer supply, livestock manure production, and nutrient balance were correlated with water quality data (T-N, T-P, BOD, and COD) for the twenty-two districts of the province. Concentration of T-N were positively correlated with chemical fertilizer supply, livestock manure N production, and nutrient balance (P<0.05 or P<0.01). Meanwhile, T-P concentration was not correlated with these nutrient indices; however, there was a tendency that T-P concentration increases with livestock manure P production (P=0.06) and with nutrient balance (P=0.09). These results suggest that T-N concentration is susceptible to both chemical fertilizer and livestock manure; whereas T-P is likely to be affected by livestock manure rather than chemical fertilizer. The concentrations of BOD and COD were also positively (P<0.05 or P<0.01) correlated with livestock manure production. CONCLUSION: This study shows the usefulness of nutrient indices in understanding spatial variations of water quality and suggests that livestock manure rather than chemical fertilizer can be a more critical water pollution source and thus highlights the need for more attention to livestock manure treatments for rural water quality management.

Single Nucleotide Polymorphisms (SNPs) Discovery in GHSR Gene and Their Association Analysis with Economic Traits in Korean Native Chickens (GHSR 유전자 내 유전변이의 탐색과 한국재래계의 성장 및 산란 특성에 미치는 연관성 분석)

  • Choi, So-Young;Hong, Min-Wook;Yang, Song-Yi;Kim, Chong-Dae;Jeong, Dong Kee;Hong, Yeong Ho;Lee, Sung-Jin
    • Korean Journal of Poultry Science
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    • v.43 no.4
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    • pp.273-279
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    • 2016
  • Recently, it was reported that certain polymorphisms in the growth hormone secretagogue receptor gene (GHSR) are associated with the growth of chickens. However, the correlation between GHSR polymorphisms and economic traits has not been investigated in Korean native chickens (KNCs). Therefore, the objective of this study was to confirm the suitability of the GHSR gene as a candidate for genomic selection and identify a genetic marker for KNCs. A total of 220 KNCs from six breeds raised at the National Institute of Animal Science were genotyped for the c.739+726 SNP in the GHSR gene using polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP), and the sequence for a subset of 30 birds was analyzed using direct sequencing. The association between the SNP genotypes and the economic traits of the KNCs was analyzed using the statistical package for the social science (SPSS) software program. The association analysis between the c.739+726T>C SNP and economic traits revealed that the SNP was significantly associated with body weight at 150 and 270 days (BW150 and BW270, respectively) in all KNCs (p<0.01), BW150 in KNC (Gary) (p<0.05), and egg production number in KNC (White, p<0.05). In addition, the SNPs discovered using direct sequencing (513A>G, 517A>T) had a significant effect on the body weight and egg production traits (p<0.05). In conclusion, these results might be useful as a basis for studies on the improvement of KNC breeds. Furthermore, these results suggest that the SNPs (c.739+726T>C, 513A>G, and 517A>T) located in the GHSR gene could be useful molecular genetic markers for KNCs.

Screening of Effective Extraction Conditions for Increasing Antioxidant Activities of Licorice Extracts from Various Countries of Origin (원산지별 감초추출물의 항산화활성 증가를 위한 효율적인 추출조건 탐색)

  • Ha, Ji Hoon;Lee, Hye Mi;Kwon, Soon Sik;Kim, Hae Soo;Kim, Moon Jin;Jeon, So Ha;Jeong, Yoo Min;Hwang, Jun Pil;Park, Jong-Ho;Choi, Yung-Key;Park, Jino;Park, Soo Nam;Park, Dong-Sik
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.4
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    • pp.259-269
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    • 2013
  • In this work, licorice extracts were prepared using various extraction conditions such as extraction solvent, temperature, and time from Glycyrrhiza uralensis (G. uralensis) produced in Korea and China and Glycyrrhiza glabra (G. glabra) in Uzbekistan. The optimum extraction condition was selected from the extraction yields and antioxidative activities of extracts. Korea licorice extracts showed the highest free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity (46.05%) under the extraction condition of 85% ethanol at $60^{\circ}C$ for 6 hours. The prominent ROS (reactive oxygen species) scavenging activity using luminol-dependent chemiluminescence assay and the cellular protective effect against $^1O_2$ induced cellular membrane damage were also shown from the extracts obtained from the same condition. Especially, Korea G. uralensis extracts exhibited the higher prominent protective effect (${\tau}_{50}$ = 116.4 min) than (+)-(+)-${\alpha}$-tocopherol (${\tau}_{50}$ = 28.5 min) and the extraction yield of Korea licorice extract was 18.75%, which is 1.2 times and 2.5 times higher than that of Uzbekistan and China, respectively. These results indicate that the extraction condition of 85% ethanol at $60^{\circ}C$ for 6 hours is optimal to prepare licorice extracts, which can be applicable as anti-oxidative cosmetic materials.

Preventive Characteristics of Garlic Extracts Using in vitro Model System on Alzheimer's Disease (In vitro model system을 활용한 마늘 추출물의 치매예방 특성)

  • Choi, Gwi-Nam;Kim, Ji-Hye;Kwak, Ji-Hyun;Jeong, Chang-Ho;Jeong, Hee-Rok;Shin, Jung-Hye;Kang, Min-Jung;Sung, Nak-Ju;Heo, Ho-Jin
    • Journal of agriculture & life science
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    • v.44 no.4
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    • pp.45-55
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    • 2010
  • In this study, the acetylcholinesterase (AChE) inhibition and neuronal cell protective effects of water, 100% methanol and dichlromethane extracts from garlic were investigated. We found that dichloromethane extract of garlic resulted in a dose-dependent manner on AChE inhibition ($IC_{50}$: $36.1{\mu}g/mL$). In cell viability assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT), cell viabilities of water, 100% methanol and dichlromethane extracts were lower (almost under 40%) than amyloid ${\beta}$ protein ($A{\beta}$)-induced neurotoxicity. Because $A{\beta}$ is also known to increase neuronal cell membrane breakdown, neuronal apoptosis was further confirmed by lactate dehydrogenase (LDH) and neutral red uptake (NRU) assay. Water extract presented relative protection against $A{\beta}$-induced membrane damage in LDH assay. However all garlic extracts showed significant problem with decrease of cell viability in NRU assay, especially at dichloromethan extract. To determine active compounds in column fractions (98:2 fraction) from dichloromethane extract which showed significant AChE inhibitory effect, we performed HPLC and LC-MS analysis. It was supposed that garlic may contain allyl methyl disulfide, diallyl monosulfide, and diallyl disulfide as active compounds.

Biological Toxicity Assessment of Sediment at an Ocean Dumping Site in Korea (폐기물 배출해역 퇴적물의 생물학적 독성평가 연구)

  • Seok, Hyeong Ju;Kim, Young Ryun;Kim, Tae Won;Hwang, Choul-Hee;Son, Min Ho;Choi, Ki-young;Kim, Chang-joon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.1
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    • pp.1-9
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    • 2022
  • The effect of sediments in a waste dumping area on marine organisms was evaluated using sediment toxicity tests with a benthic amphipod (Monocorophium acherusicum) and bioluminescent bacterium (Vibrio fischeri) in accordance with the Korean Standard Method for Marine Wastes (KSMMW). Nine sites in the East Sea-Byeong, East Sea-Jeong, and Yellow Sea-Byeong areas were sampled from 2016 to 2019. The test results showed that the relative average survival rate (benthic amphipods) and relative luminescence inhibition rate (luminescent bacteria) were below 30%, which were judged to be "non-toxic." However, in the t-test, a total of 12 benthic amphipod samples (6, 1, 1, and 4 in 2016, 2017, 2018, and 2019, respectively) were significantly different (p<0.05) from the control samples. To identify the source of toxicity on benthic amphipods, a simple linear regression analysis was performed between the levels of eight heavy metals (Cr, As, Ni, Cd, Cu, Pb, Zn, and Hg) in sediments and the relative average survival rate. The results indicated that Cr had the highest contribution to the toxicity of benthic amphipods (p = 0.000, R2 = 0.355). In addition, Cr was detected at the highest concentration at the DB-85 station and exceeded the Marine Environment Standards every year. Although the sediments were determined as "not toxic" according to the ecotoxicity criteria of the KSMMW, the results of the statistical significance tests and toxicity identification evaluation indicated that the toxic effect was not acceptable. Therefore, revising the criteria for determining the toxic effect by deriving a reference value through quantitative risk assessment using species sensitivity distribution curves is necessary in the future.

Antioxidant Effects of Cysteine-containing Peptides of Different Lengths in Human HaCaT Keratinocytes Exposed to Hydrogen Peroxide (과산화수소에 노출된 인간 각질형성세포에서 길이가 다른 시스테인 함유 펩타이드의 항산화 효과)

  • Jae Won Ha;Joon Yong Choi;Yong Chool Boo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.3
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    • pp.193-201
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    • 2023
  • Hydrogen peroxide (H2O2) is a type of active oxygen species (ROS) that causes oxidative stress in cells and affects cell growth, proliferation, senescence, and death. The purpose of this study is to find active peptides that attenuate cytotoxicity of H2O2. A positional scanning synthetic tetrapeptide combinatorial library was screened to predict the sequence of potentially active peptides. As a result of comparing the effect of peptide pools on H2O2-induced death of human keratinocytes (HaCaT cells), various active peptide sequences were predicted. Especially, peptides containing cysteine (C) residue were predicted to be active. In follow-up experiments, the cytotoxicity and activity of cysteine-containing peptides of different lengths, such as C-NH2, CC-NH2, CCC-NH2, and CCCC-NH2 were examined. C-NH2 and CC-NH2 showed no significant cytotoxicity up to 1.0 mM, but CCC-NH2, and CCCC-NH2 showed relatively strong cytotoxicity. C-NH2 and CC-NH2 alleviated H2O2-induced cytotoxicity. CC-NH2 was more cytoprotective compared to C-NH2, C, N-acetyl cysteine (NAC), and glutathione (GSH). When intracellular ROS was measured by flow cytometry, H2O2 increased ROS production, and CC-NH2 suppressed ROS production more effectively than C-NH2, and it was as effective as C, NAC, and GSH. This study suggests that CC-NH2 of the cysteine-containing peptides of different lengths has an antioxidant property that safely and effectively alleviates H2O2-induced cytotoxicity and ROS production.