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Current Status of the Research on the Postharvest Technology of Melon(Cucumis melo L.) (멜론(Cucumis melo L.) 수확 후 관리기술 최근 연구 동향)

  • Oh, Su-Hwan;Bae, Ro-Na;Lee, Seung-Koo
    • Food Science and Preservation
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    • v.18 no.4
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    • pp.442-458
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    • 2011
  • Among Cucubitaceae, melon (Cucumis melo) is one of the most diversified fruits, with various forms, sizes, pulps, and peel colors, In addition, it is a commercially important crop because of its high sweetness, deep flavor, and abundant juice. In the species, there are both climacteric and non-climacteric melons depending on the respiration and ethylene production patterns after harvest. Ethylene is also considered a crucial hormone for determining sex expression, Phytohormones other than ethylene interact and regulate ripening, There are some indices that can be used to evaluate the optimum harvest maturity. The harvest time can be estimated after the pollination time, which is the most commonly used method of determining the harvest maturity of the fruit. Besides the physiological aspects, the biochemical alterations, including those of sweetness, firmness, flavor, color, and rind, contribute to the overall fruit quality. These changes can be categorized based on the ethylene-dependent and ethylene-independent phenomena due to the ethylene-suppressed transgenic melon. After harvest, the fruits are precooled to $10^{\circ}C$ to reduce the field heat, after which they are sized and packed. The fruits can be treated with hot water ($60^{\circ}C$ for 60 min) to prevent the softening of the enzyme activity and microorganisms, and with calcium to maintain their firmness. 1-methylenecyclopropene (1-MCP) treatment also maintains their storability by inhibiting respiration and ethylene production. The shelf life of melon is very short even under cold storage, like other cucurbits, and it is prone to obtaining chilling injury under $10^{\circ}C$. In South Korea, low-temperature ($10^{\circ}C$) storage is known to be the best storage condition for the fruit. For long-time transport, CA storage is a good method of maintaining the quality of the fruit by reducing the respiration and ethylene. For fresh-cut processing, washing with a sanitizing agent and packing with plastic-film processing are needed, and low-temperature storage is necessary. The consumer need and demand for fresh-cut melon are growing, but preserving the quality of fresh-cut melon is more challenging than preserving the quality of the whole fruit.

Quality characteristics of farm-made brown rice vinegar via traditional static fermentation (전통정치배양에 의한 농가형 현미식초의 품질특성)

  • Baek, Chang Ho;Jeong, Da-Hee;Baek, Seong Yeol;Choi, Ji-Ho;Park, Hye-Young;Choi, Han Seok;Jeong, Seok-Tae;Kim, Jae Hyun;Jeong, Yong-Jin;Kwon, Joong-Ho;Yeo, Soo-Hwan
    • Food Science and Preservation
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    • v.20 no.4
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    • pp.564-572
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    • 2013
  • We investigated the quality characteristics of brewing brown rice vinegar through a traditional static fermentation process. Accordingly, we decided to compare the physicochemical characteristics of brewing vinegar at different temperatures and filtration methods. In four to five weeks' time, the acetic acid fermentation exhibited the highest titratable acidity and then it eventually decreased. The titratable acidity was affected by the filtration method. It was revealed that the titratable acidity was higher in the forced filtration than the traditional filtration method. Various organic acids were detected in order to initialize the fermentation stage and as the fermentation progressed, only the acetic acid could be detected. The total free amino acid content was higher at a temperature of $30^{\circ}C$ than at $20^{\circ}C$. Moreover, the free amino acid content was dependent on the acetate content during the acetic fermentation process. The main bioactive substance of the ${\gamma}$-aminobutyric acid content was more than twice at a fermentation temperature of $30^{\circ}C$ compared to the fermentation temperature of $20^{\circ}C$. Furthermore, the total amino acid and essential amino acid content at a temperature of $30^{\circ}C$ was excellent. The quality of the brown rice vinegar via forced filtration method at a temperature of $30^{\circ}C$ was the most excellent. Based on these results, the fermentation temperature and the use of nuruks (fermenting agent) affected the quality of the brown rice vinegar, and an appropriate method to consider its purpose is required.

Enhanced production of monacolin-K through supplement of monacolin-K precursors into production medium and cloning of SAM synthetase gene (metK) (Precursor제공 및 생합성 관련 유전자의 cloning을 통한 Monacolin-K 생산성 향상)

  • Lee, Mi-Jin;Jeong, Yong-Seob;Chun, Gie-Taek
    • KSBB Journal
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    • v.23 no.6
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    • pp.519-524
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    • 2008
  • Monacolin-K is a strong anti-hypercholesterolemic agent produced by Monascus sp. via polyketide pathway. High-yielding mutants of monacolin-K were developed through rational screening strategies adopted based on understanding of monacolin-K biosynthetic pathway. Through the experiments for investigating various amino acids as putative precursors for the monacolin-K biosynthesis, it was found that production level of monacolin-K was remarkably increased when optimum amount of cysteine was supplemented into the production medium. We suggested that these phenomena might be related to the special roles of SAM (S-adenosyl methionine), a putative methyl group donor in the biosynthetic pathway of monacolin-K, demonstrating close interrelationship between SAM-synthesizing primary metabolism and monacolin-K synthesizing secondary metabolism. Namely, increase in the intracellular amount of SAM derived from the putative precursor, cysteine which was extracellularly supplemented into the production medium might contribute to the significant enhancement in the monacolin-K biosynthetic capability of the highly mutated producers. On the basis of these assumptions derived from the above fermentation results, we decided to construct efficient expression vectors harboring SAM synthetase gene (metK) cloned from A. nidulans, with the hope that increased intracellular level of SAM could lead to further enhancement in the monacolin-K production through overcoming a rate-limiting step associated with monacolin-K biosynthesis. Hence, in order to overcome the plausible rate-limiting step associated with monacolin-K biosynthesis by increasing intracellular level of SAM, we transformed the producer mutants with an efficient expression vector harboring gpdA promoter of the producer microorganism, and metK gene. Notably, from the resulting various transformants, we were able to screen a very high-yielding transformant which showed approximately 3.3 fold higher monacolin-K productivity than the parallel nontransformed mutants in shake flask cultures performed under the identical fermentation conditions.

Effects of a Soil-Born Paenibacillus spp. Strain KPB3 on Suppression of Bacterial Wilt Disease Caused by Ralstonia solanacearum (토양에서 분리한 Paenibacillus spp. KPB3의 Ralstonia solanacearum에 의한 세균성 풋마름병 억제 효과)

  • Suk, Jung-Ki;Ipper, Nagesh S.;Lee, Seon-Hwa;Shrestha, Anupama;Park, Duck-Hwan;Cho, Jun-Mo;Hur, Jang-Hyun;Kim, Byung-Sup;Lim, Chun-Keun
    • The Korean Journal of Pesticide Science
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    • v.10 no.4
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    • pp.313-319
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    • 2006
  • Two hundred bacterial strains were isolated from the soil around healthy tomato plants in a polyvinyl house, where most of the other plants showed bacterial wilt symptoms. The strains were screened in vitro for their antibacterial activity. Among them, a strain, KPB3 showed strong bactericidal activity against bacterial wilt pathogen, Ralstonia solanacearum. The strain KPB3 was identified using physiological and biochemical tests, and 16S rRNA analyses. Based on these tests, the strain was found to be closer to genus Paenibacillus. To control the bacterial wilt caused by R. solanacearum, greenhouse experiments were conducted to determine the effectiveness of the Paenibacillus strain KPB3. Drench application of this strain ($4{\times}10^8$ CFU $mL^{-1}$) into the pots containing tomato plants, post-inoculated with the pathogen, R. solanacearum could drastically reduce the disease severity, compared to the non-treated plants. To evaluate effectiveness of this strain under field conditions, experiments were carried out in polyvinyl houses infested with R. solanacearum, during spring and autumn of the year 2006. It was observed that, during spring, bacterial wilt was more prevalent compared to the autumn. During spring, 50.9% disease incidences occurred in non-treated controls, while, Paenibacillus strain KPB3 treated plants showed 24.6% disease incidences. Similarly, during autumn, around 17.2% plants were infected with bacterial wilt in non- treated polyvinyl houses, compared to the Paenibacillus strain KPB3 treated plants, which showed 7.0% disease incidences. These results demonstrated that, Paenibacillus strain KPB3 is a potential biological control agent against bacterial wilt caused by R. solanacearum, effective under greenhouse as well as field conditions. This is the first report showing biocontrol of R. solanacearum using a Paenibacillus spp. under field conditions.

On the Utilization of Inactive BHC isomers -Synthesis of 3-(2,4,5-trichlorophenyl)-1-methyl urea as a herbicide- (BHC 이성질체(異性質體)의 활용(活用)에 관(關)한 연구(硏究) -제초제(除草劑)로서 3-(2,4,5-trichlorophenyl)-1- methyl urea의 합성(合成)-)

  • Lee, Kyu-Seung;Park, Chang-Kyu
    • Applied Biological Chemistry
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    • v.22 no.2
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    • pp.109-122
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    • 1979
  • Present study was carried out to reduce residual toxicity of BHC insecticides inherent in the organochlorine pesticides. For This end, r-isomer, the most potent insecticidal component among the BHC stereoisomers, was isolated and thus fortified by means of solvent precipitation. In parallel, 3-(2,4,5-trichlorophenyl)-1-methyl urea was prepared in good yield from technical BHC via 1,2,4-trichlorobenzene, 1,2,4,-trichloronitrobenzene, and 2,4,5-trichloroaniline. In addition, certain merit of the compound which make it possible to use as a herbicide is discussed. The results are summarized as follows; 1. Recrystallizing technical BHC from methanol-water binary solvent system, r-isomer was enriched to 49.7% at 95% recovery of r-isomer. 2. By partitioning technical BHC in 85% of methanolic solution into chloroform, r-isomer was fortified to 89.6% at 90.5% recovery of r-isomer. 3. Yield of 1,2,4-trichlorobenzene from technical BHC was greatly dependent upon concentration of alkalies and to less degree on the alkalies. 4. Surfactants, in particular cationic a quartenary ammonium salt, increased yield of 1,2,4-trichlorobenzene from technical BHC by alkaline hydrolysis. 5. Conversion of 1,2,4-trichlorobenzene to 2,4,5-trichloronitrobenzene was effected almost quantitatively utilizing $HNO_3-H_2SO_4$ nitrating agent at low temperature. 6. Yield of 91.4% was observed for the synthesis of 2,4,5-trichloroaniline by reducing 2,4,5-trichloronitrobenzene in the presence of iron turning and hydrochloric acid. 7. Overall yield based on BHC of 3-(2,4,5-trichlorophenyl)-1- methyl urea was 60.8%. 8. Inhibition effects, both germination and growth, 3-(2,4,5-trichlorophenyl)-1-methyl urea on several crops were found comparable to or more potent than those of $linuron{\circledR}\;and\;diuron{\circledR}$. In addition, it was also noted that susceptibility to the prepared compound depended upon the crops as well as specific part (shoots, roots) of the plant exposed to the chemicals.

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Critical Analysis about Environmental Ethics and Moral Position of Landscape Architecture - Focusing on Eugen C. Hargrove's 'Weak Anthropocentrism' - (조경의 환경윤리에 대한 비판적 해석과 도덕적 위치 - 유진 하그로브의 '약한 인간중심주의'를 중심으로 -)

  • Oh, Chang-Song
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.2
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    • pp.105-113
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    • 2015
  • The theory of landscape architecture applies environmental ethics in order to secure an ecological status. However, environmental ethics that focus on nature conservation excludes landscape architecture as artifacts. In the process, it is hard to identify what landscape architecture insists on as the middle position between humans and nature. Rather, landscape architecture pretends to be an 'agent of nature' and pushes the traditional moral values 'for people.' Therefore, the purpose of this study is to reestablish the anthropocentrism moral position of landscape architecture through critical analysis. Hargrove's weak anthropocentrism' of several environmental ethics branches accepts natural aesthetics(such as landscape architecture) as an ethical virtue. But environmental ethics makes landscape architecture a critical target. For that reason, this study looked into critical contents and objects that in a position to moral, aesthetic and landscape architecture. Critical details are as follows: First, nature is an absolute as an aesthetic and moral value, but landscape architecture is an imitation and takes a relaxed attitude about nature. Second, nature is full of aesthetic substance because it is self-creative, but landscape architecture is designed nature covered human flaws through imagination. Third, environmental management granting techniques in nature generate a moral nihilism. As an argument, environmental ethics overlooked the moral practices of landscape architecture beyond nature another moral aspect of creation and the imagination-and moral aspects of environmental management as 'care' because they rule out 'moral autonomy' and simplify what is considered 'good.' As a result, conservation cannot be the only virtue why the problem of nature in reality cannot be separated from human life. The moral position of landscape architecture based on a 'good life' is more appropriate under anthropocentrism than as a middle position.

THE INFLUENCE OF CAVITY CONFIGURATION ON THE MICROTENSILE BOND STRENGTH BETWEEN COMPOSITE RESIN AND DENTIN (와동의 형태가 상아질과 복합레진 사이의 미세인장결합강도에 미치는 영향)

  • Kim, Ye-Mi;Park, Jeong-Won;Lee, Chan-Young;Song, Yoon-Jung;Seo, Deok-Kyu;Roh, Byoung-Duck
    • Restorative Dentistry and Endodontics
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    • v.33 no.5
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    • pp.472-480
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    • 2008
  • This study was conducted to evaluate the influence of the C-factor on the bond strength of a 6th generation self-etching system by measuring the microtensile bond strength of four types of restorations classified by different C-factors with an identical depth of dentin. Eighty human molars were divided into four experimental groups, each of which had a C-factor of 0.25, 2, 3 or 4. Each group was then further divided into four subgroups based on the adhesive and composite resin used. The adhesives used for this study were AQ Bond Plus (Sun Medical, Japan) and XenoIII (DENTSPLY, Germany). And composite resins used were fantasists (Sun Medical, Japan) and Ceram-X mono (DENTSPLY, Germany). The results were then analyzed using one-way ANOVA, a Tukey's test, and a Pearson's correlation test and were as follows. 1. There was no significant difference among C-factor groups with the exception of groups of Xeno III and Ceram-X mono (p<0.05). 2. There was no significant difference between any of the adhesives and composite resins in groups with C-factor 0.25, 2 and 4. 3. There was no correlation between the change in C-factor and microtensile bond strength in the Fantasista groups. It was concluded that the C-factor of cavities does not have a significant effect on the microtensile bond strength of the restorations when cavities of the same depth of dentin are restored using composite resin in conjunction with the 6th generation self-etching system.

New Whitening Agent : Selina-4(14), 7(11)-dien-8-one (신규 미백제 : Selina-4(14), 7(11)-dien-8-one)

  • Kim, Cheong-Taek;Chang, Yun-Hee;Lee, Sang-Hwa;Kang, Sang-Jin;Cho, Wan-Goo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.31 no.1 s.49
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    • pp.17-23
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    • 2005
  • We had previously reported that Selina (selina-4(14), 7(11)-dien-8-one) was isolated from methanol extract of Afractylodes rhizome and has strong whitening activity in B16 melanoma cells. In this report, we demonstrated its action mechanism in melan-a cells, non-tumorigenic melanocytes. We also investigated the clinical efficacy of cosmetic preparation containing Selina. Selina reduced the melanin synthesis of Melan-a cells by $50\%$ at a concentration of $10 {\mu}g/mL$ without any apparent cytotoxicity. We also found that the treatment of cells with Selina decreased tyrosinase activity by $60\%$ at a concentration of $10 {\mu}g/mL$ but Selina was not a direct inhibitor of tyrosinase activities. To elucidate the action mechanism of Selina, we investigated the changes in mRNA and protein level of tyrosinase, TRP-1 and TRP-2 using RT-PCR and western blotting, respectively. As a result, the mRNA and protein level of tyrosinase were markedly reduced at $10 {\mu}g/mL$ of Selina without any effect on TRP-1 and TRP-2. These results suggest that Selina exerts its whitening effect mainly through regulating expression of tyrosinase. A 7 week-clinical trial using formulation containing $0.2\%$ selina-4(14), 7(11)-dien-8-one with 20 volunteers resulted in statistically significant whitening effect (p < 0.05), without any adverse effect. Based on these results, Selina (selina-4(14), 7(11)-dien-8-one) can be s useful and safe ingredient for the cleanness and brightness of skin.

A Study on Archiving of 'Social Memory' and Oral Record Focused on the Role of Archivist in the Stages of Oral Record Collecting and Planning (사회적 기억과 구술 기록화 그리고 아키비스트)

  • Choi, Jeong-eun
    • The Korean Journal of Archival Studies
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    • no.30
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    • pp.3-55
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    • 2011
  • Recently, a topic of Archival Science can be said 'paradigm shift'. Therefore, this study aims to establish a relationship between oral record and Archival Science through concept of the archiving 'social memory' related to paradigm shift of Archival Science. In addition, an active role theory by an archivist as main agent of archival oral record management reflecting the characteristics of oral record based on this will be supported. Especially, even if it has already been handled through previous studies, it will be focused on drawing new meaning by applying creative perspective. Main content of this study is as follows. Firstly, discussion will be progressed by establishing the concept of the archiving 'social memory'. This is related to the topic of 'paradigm shift' in the Archival Science. Despite that active research has been conducted among mainly archival researchers overseas, it has not been handled yet in Korea. Therefore, this study aims to determine to organize this part as detail purpose. Secondly, the point will be progressed with a special focus on collecting and planning stages among the stages of records management. A viewpoint of the Archival Science should start from the stage of collecting and planning the previous record of production point of time, and then should be reflected for acknowledging the subsequent stages. Therefore, collecting and planning are the most important, and this is closely connected with a characteristic of oral record which production means collecting. Thirdly, the concept of 'oral record' is established with the viewpoint of the Archival Science. The various documents have been producted through oral interview has been known to many oral history researchers as 'oral source'. It aims to conceptualize them as 'oral record' with the viewpoint of the Archival Science. Fourthly, it is an establishment of meaning why oral history should be handled in the Archival Science. It is necessary to rationalize the purpose and its appropriateness handling oral history in the Archival Science. It should clarify the reason why oral history is important in the Archival Science and what it means. This will help examine the meaning of the recording of 'oral record.' A characteristic of the oral record can be effectively revealed through the recording, and ultimately, it aims to be able to shed new light on the value of oral history and oral record. Finally, it defines the role of archivist in oral history. A point that archivist in oral history is not just an assistant who organizes and preserves oral records collected by researchers will be emphasized and persuaded. In this study, oral history study in the Archival Science which has obtained appropriateness by the theoretical discussion as above should be conducted in a connection with other studies without occupying oral history by the Archival Science and in a direction of the leap of Korean oral history study. If this is possible, it will contribute to development of the Archival Science and of study area expansion, enhancement of the role and potential of archivist, at the same time, eventually it will positively influence on oral history study.

The Radioprotection Effect of Protaetia Brevitarsis Larvae Extracts on the Reproductive in Female Rats Irradiated Gamma Ray (감마선에 조사된 암컷 흰쥐의 생식기관에 대한 흰점박이꽃무지 유충 추출물의 방사선 방호효과)

  • Jeong, Geun-Woo;Joung, Do-Young;Kim, Chang-Ju;Lee, Ji-Eun;Jeong, Sang-Hyun;Kim, Hee-Jin;Min, Byung-In
    • Journal of the Korean Society of Radiology
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    • v.15 no.2
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    • pp.247-255
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    • 2021
  • The purpose of this study was to examine the radiation protection effect of protaetia brevitarsis larvae extracts known as antioxidant food. In this study 90 female rats were clssified in to 5 groups: NC Group, PBE Group, IR Group, PBE+IR Group and IR+PBE Group. In IR Group, 7 Gy of Co-60 gamma ray was irradiated to SD rat and protaetia brevitarsis larvae extracts were administered orally at 200 mg/kg once a day for 14 days. And then on the 1 day, 7 days, 21 days later after irradiation, changes in blood cell component, superoxide dismutase(SOD) activity, spleen index, histopathological evaluation of the ovary and uterus were observed. As a result, the PBE+IR Group (p<0.01, p<0.05) and IR+PBE Group (p<0.01, p<0.01) showed a significantly radiation protection than the IR Group in lymphocyte and red blood cell on the 21 days. It was also confirmed that SOD activity of PBE+IR Group (p<0.01) and IR+PBE Group (p<0.01) was significantly increased than the IR Group. In spleen index, PBE+IR Group (p<0.05) and IR+PBE Group (p<0.01) showed a significantly recovery than the IR Group. In histopathological observation, PBE+IR Group in the ovary and PBE+IR, IR+PBE Group in the uterus showed less inflammatory reactions of cystoplasm than the IR Group. Based on These results, It is judged that protaetia brevitarsis larvae Extracts have radiation protection effect against blood and reproductive. It is expected to be useful for research of radiation protection agent.