• Title/Summary/Keyword: Growth condition

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Antifungal Activity of Bacillus Subtilis HK2 against Trichothecium Roseum Causing Pink Rot of Melon and White Stain Symptom on Grape (멜론 분홍빛썩음병과 포도 흰얼룩병의 원인균인 Trichothecium Roseum에 대한 Bacillus Subtilis HK2의 항균활성)

  • Oh, Soh-Young;Lee, En-Young;Nam, Ki-Woong;Yoon, Deok-Hoon
    • Korean Journal of Plant Resources
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    • v.29 no.1
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    • pp.39-45
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    • 2016
  • Pink Rot on melon and White Stain Symptom on grape are caused by Trichothecium roseum, one of the most important diseases of grape and melon. These diseases have been occurred in national-wide in Korea and causes irreversible damage on the grape and the melon at harvest season. This research presents the evaluation of the capacity of Bacillus subtillis HK2 to protect both melon and grape against T. reseum and establishes its role as a biocontrol agent. In this study, we isolated a Bacillus strain HK2 from rhizosphere soil, identified it as Bacillus subtillis by 16S rRNA analysis and demonstrated its antifungal activity against T. roseum. Under I-plate assay it was observed that the effect of hyphal growth inhibition was not due to production of volatile compounds. The optimum culture condition of HK2 was found at 30℃ and initial pH of 7.0. Application of HK2 culture suspension reduced 90.2% of white stain symptom on grape as compared to control, resulting in greater protection to grape against T. roseum infestation. Butanol extract of HK2 culture purified using flash column chromatography. The antifungal material was a polar substance as it showed antifungal activity in polar elute. Therefore, our results indicated a clear potential of B. subtilis HK2 to be used for biocontrol of Pink rot in melon and white stain symptom on grape caused by T. roseum.

Effects of Yeast Addition as Starter on Fermentation of Kimchi (효모 Starter 의 첨가가 김치발효에 미치는 영향)

  • Kim, Hye-Ja;Kang, Sang-Mo;Yang, Cha-Bum
    • Korean Journal of Food Science and Technology
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    • v.29 no.4
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    • pp.790-799
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    • 1997
  • The purpose of this study is to investigate the effects of yeast addition as starter on kimchi fermentation. The strains used as starter were Saccharomyces sp. YK-17 and Saccharomyces fermentati YK-19 isolated from kimchi, grew under anaerobic condition and low temperature, which showed the acid and base resistances. Chemical and microfloral changes, as well as the sensory properties of starter added kimchi during fermentation were compared with the control fermented without starter. The acidity of kimchi juice was lower and pH was higher in starter added kimchi than the control. Particularly addition of S. fermentati YK-19 prolonged the optimally fermented period (pH 4.0, acidity $0.6{\sim}0.8%$) up to more than 63%. The content of lactic acid, the major non-volatile organic acid in kimchi, was increased rapidly followed by S. sp. YK-17 and S. fermentati YK-19 group. The microfloral changes were found a little different among the samples. Among the microorganisms, Leuconostoc sp. and Lactobacillus sp. showed highest change, and Streptococcus sp. and Pediococcus sp. showed ralatively low change. The growth of Lactobacillus sp. which was the main acidifing microorganism was inhibited by starter addition, particularly by S. fermentati YK-19. The sensory characteristics of acidic and moldy flavor were significantly reduced by the addition, while fresh flavor was increased in starter added group.

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Isolation and Identification of Cellulase-producing Microorganism, and Determination of Optimal Culture Condition (토양으로부터 Cellulose 분해효소를 생산하는 미생물의 분리, 동정 및 최적배양조건의 결정)

  • Hahm, Byoung-Kwon;Kim, Yoon-Keun;Yu, Ju-Hyun;Bai, Dong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.29 no.5
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    • pp.1028-1032
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    • 1997
  • The strain No. 33, which produces cellulose-degrading enzyme, was isolated from soil. Yellow halo was identified when the culture supernatant of the strain was loaded onto agar plate containing 2.0% CMC using paper disc method. From scanning electron microscopic observation, the morphology of the stain was rod-shaped. For identification, several biochemical characteristics were tested, and this strain was identified to Bacillus sp. So, we named this strain as Bacillus sp. No. 33. The maximal growth was observed when the stain was cultured in the medium containing 1.0% glucose, 3.0% yeast extract, 0.5% $KH_2PO_4$, 0.02% $MgSO_4{\cdot}7H_2O$, pH 7.0 at $30^{\circ}C$ for 39 hours with shaking. The maximal enzyme production was accomplished using the medium containing 4.0% CMC, 2.0% yeast extract, 0.5% $KH_2PO_4$, 0.04% $MgSO_4{\cdot}7H_2O$, pH 7.0 at $30^{\circ}C$ for 42 hours with shaking.

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Characterization of Antibacterial Substance - Producing Bacillus subtilis Isolated from Traditional Doenjang (전통 된장으로부터 분리한 향균물질 생산 Bacillus subtilis의 특성)

  • Ryu, Hyun-Soon;Shon, Mi-Yae;Cho, Soo-Jeong;Park, Seok-Kyu;Lee, Sang-Won
    • Applied Biological Chemistry
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    • v.50 no.2
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    • pp.87-94
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    • 2007
  • A bacterium which has high enzymatic activities such as amylase, cellulase and protease was isolated from Korean traditional soybean food, doenjang. The isolated bacterium was identified to Bacillus subtilis HS25 by the test of morphological and biochemical properties according to Bergey's Manual of Systematic Bacteriology and API 50 CHL kit, and by the 16S rDNA sequence. The isolated B. subtilis HS25 had a potent antibacterial activity against food born causative or pathogenic bacteria. B. subtilis HS25 is endospore forming cell and contained flagella and abundant viscous material at the out layer of cell wall. It was rod type bacterium $(0.5{\sim}0.8{\times}3{\sim}5{\mu}m)$ having biochemical characteristics such as gram staining(+), catalase(+), oxidase(-) and hydrolysis of esculin(+). The optimal medium compositions for production of antibacterial substance in the B. subtilis HS25 were 1% of soluble starch, 0.5% of yeast extract, 0.5% of peptone and 0.05% of MgCl$_2{\cdot}6H_{2}O$. The optimum temperature and pH of the growth of the B. subtilis HS25 was 35$^{\circ}C$ and pH 7.5, respectively. The antibacterial activity was more high in neutral to a little alkaline pH (6.5-10.5) than in acidic pH. The optimal shaking speed to grow and to produce antibacterial substance of the B. subtilis HS25 was 160${\sim}$200 rpm. The optimal culture time for antibacterial activities of the bacterium were shown to be in the range of 12-36 hr.

Geographical Shift in Blooming Date of Kiwifruits in Jeju Island by Global Warming (지구온난화에 따른 제주도 내 참다래 개화일의 지리적 이동)

  • Kwon, Young-Soon;Kim, Soo-Ock;Seo, Hyeong-Ho;Moon, Kyung-Hwan;Yun, Jin I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.14 no.4
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    • pp.179-188
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    • 2012
  • A kiwifruit cultivar 'Hayward' has been grown in Jeju Island where the current climate is suitable for growth and development of this crop. Prediction of the geographical shift in the phenology can help the kiwifruits growers to adapt to the local climate change in the future. Two phenology models (i.e., chill-day and DVS) were parameterized to estimate flowering date of kiwifruits 'Hayward' based on the data collected from field plots and chamber experiments in the southern coastal and island locations in South Korea. Spatio-temporally independent datasets were used to evaluate performance of the two models in predicting flowering date of 'Hayward'. Chill-day model showed better performance than DVS model (2.5 vs. 4.0 days in RMSE). Daily temperature data interpolated at a higher spatial resolution over Jeju Island were used to predict flowering dates of 'Hayward' in 2021-2100 under the A1B scenario. According to the model calculation under the future climate condition, the flowering of kiwifruits shall accelerate and the area with poor flowering might increase due to the warmer winter induced insufficient chilling. Optimal land area for growing 'Hayward' could increase for a while in the near future (2021-2030), whereas such areas could decrease to one half of the current areas by 2100. The geographic locations suitable for 'Hayward' cultivation would migrate from the current coastal area to the elevated mountain area by 250 m.

A Study on CSV of Social Economy and Consumer Perspective (사회적경제와 소비자 관점의 공유가치창출(CSV) 연구)

  • Lee, Young-Il;Kim, Young-Shin
    • Journal of Distribution Science
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    • v.13 no.12
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    • pp.53-63
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    • 2015
  • Purpose - Recently, creating shared value (CSV) has attracted attention through plan sustainability and the growth of corporate management. Porter and Kramer (2011) defined the core concept of CSV as social value, economic profits, improvements in the economic social condition, and reinforcing competitiveness. The purpose of CSV, which is to pursue economic profits through a social solution to the problem, agrees with managing the objective of a social enterprise that prioritizes the pursuit of profits through the realization of a social purpose. Today, CSV studies focus on CSR and sustainability and reinforce competitiveness. However, few studies focused on the social economy. Precedent studies examined CSV using a company example, and few studies exist from the perspective of consumers and the point of view of a market society. Research design, data, and methodology - Therefore, this study examines CSV in comparison to a background of the social economy. This study also investigates and analyzes the concept of social value from the point of view of consumers, social problems, consumption value, corporate value, and the influence of consumers. This article develops three hypotheses. Hypothesis 1 investigates the correlation with social innovation that consumers thought as being necessary for social innovation by a company. Hypothesis 2 is used to confirm the influence of consumers in CSV. Therefore, this article investigates the influence of consumers on consumption action for companies that are indifferent to social problems. Hypothesis 3 is used to verify the correlation between the value that consumers demand through consumption and the corporate value that companies pursue other than profits. The three hypotheses were adopted and met the standard for suitability. Results - The importance of the CSV study from the consumer perspective was confirmed using the influence of consumers on CSV. Because the objective of company activities is either the consumer or the market, the influence that extends to interactions between the company and consumers to ensure the success of a business is significant. Regarding the CSV study, because it was an initial study, various approaches are subsequently developed. However, conceptual and practical case studies on CSV currently exist that may be used to verify the factors that comprise CSV. Therefore, the company example may enable verification of the factors that influence the composition of CSV through identification from the consumer perspective. In addition, studying CSV as an action result (of consumer satisfaction, of a company's profits and competitiveness, and of society's cancellation of a social problem) may enable the realization of a practice paradigm as opposed to simply thought and faith. Conclusions - First, this study confirms the social value of a business through the feasible and common pursuit of consumers by corporations. Second, customer influence accounts for an important part of CSV. Third, shared value commonly provides a necessary advantage to consumers, corporates, and society, and contributes to the economy and healthy social development. Fourth, corporates can conduct a business, generate profits, and realize value through improvements in social problems and by addressing their competitive strengths and weaknesses.

Behavior of Nutrients along the Salinity Gradients in the Seomjin River Estuary (섬진강 하구역에서 염분경사에 따른 영양염의 거동)

  • KWON Kee-Young;MOON Chang-Ho;YANG Han-Seob
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.3
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    • pp.199-206
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    • 2001
  • Behavior of nutrients along the salinity gradients in the Seomjin River estuary was investigated in March July, September and November, 1999. Sampling sites were set based on the surface salinity during each cruise rather than geographic locations. The results suggest that source of nitrate and silicate was the Seomjin River discharge, while that of nitrite and phosphate was waste disposal from the Gwangynng Bay near the mouth of Seomjin River estuary. Ammonia was supplied inside the estuary at the region about $6\~8$ km far from Nancho Island. Strong removal behavior of some nutrient such as ammonia, phosphate and silicate was observed at $5\~15$ psu salinity area in November, where high concentrations of $chlorophyll\;a\;(>8{\mu}g/L$) occurred. High N : P ratios and entirely removal of phosphate at chlorophyll a peak region suggest that phosphate is the limiting factor for phytoplankton growth. Relatively high ratios of Rb to Ra (Rb: Fluorescence before acidification, Ra: Fluorescence after acidification) at $5\~15$ psu salinity region in November indicate that phytoplankton were in good physiological condition.

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Study on the Thermal Characteristics of Concrete Using Micro Form Admixture (마이크로기포제를 사용한 콘크리트의 열적 특성에 관한 연구)

  • Park, Young Shin;Kim, Jung Ho;Jeon, Hyun Kyu;Seo, Chee Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.2
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    • pp.101-109
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    • 2013
  • Recently, it is certain that the increase of heating and cooling energy consumption by radical change in climate condition has caused serious problems related to environmental and energy concerns associated with increase of fossil fuel usage and carbon dioxide production as well as global warming. So, various actions to reduce greenhouse gas exhaustion and energy consumption have been prepared by world developed countries. Our government has also been trying to seek energy control methods for houses and buildings by proclaiming political polices on low-carbon green growth and construction and performance standards for environment-friendly housing. The energy consumption by buildings approximately reaches 25% of total korea energy consumption, and the increasing rate of energy consumption by buildings is stiffer than the rate by the other industries. The greatest part in the buildings of the energy consumption is building facade. While lots of research projects for reducing energy consumption of the facade have been conducted, but a few research projects on concrete comprising more than 70% of outsider of buildings has been tried. This research presents here a study to improve the insulation property of structural concrete formed by micro form admixture (MFA) with experimentally reviewing the physical, mechanical and thermal characteristics of the concrete. As the results of this experiment, in the case of concrete mixed with MFA, slump loss has been improved. As the mixing ratio of MFA increases, the compressive strength is decreased and thermal conductivity is increased. Also it was found that water-cement ratio increases, the compressive strength is decreased and thermal conductivity is increased. but, there was not big influence by the change of fine aggregate ratio.

Physiological Evaluation of Transgenic Rice Developed for Drought Tolerance

  • Ghimiren Sita Ram;Park Sang-Kyu;Kang Dong-Jin;Lee In-Jung;Shin Dong-Hyun;Kim Sung-Uk;Kim Kil-Ung
    • Journal of Plant Biotechnology
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    • v.33 no.2
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    • pp.133-137
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    • 2006
  • Evaluation of physiological performance of trehalose-producing transgenic rice line was conducted to investigate drought tolerance at early growth stage. Under artificially induced drought condition of 8% polyethylene glycol 6000, this transgenic rice line had leaf photosynthetic rate of 11.08 uml CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 8.38 mmol $H_2O$ $m^{-2}s^{-1}$ and leaf water potential of -1.12 MPa after 96 hours of treatment. Nakdongbyeo, the parent of this tyansgenic rice line, had photosynthetic rate of 15.42 $\mu$mol CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 8,04 mmol $H_2O$ $m^{-2}s^{-1}$ and leaf water potential of -0.88 MPa. The other variety used in this experiment for comparison, IR 72, showed higher values than both tyansgenic rice line and variety Nakdonbyeo on all three parameters; leaf photosynthetic rate of 20.61 $\mu$mol CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 12.88 mmol $H_2O$ $m^{-2}s^{-1}$, and leaf water potential of -0.82 MPa. So this transgenic rice line did not show superior performance in leaf transpiration rate, leaf photosynthetic rate and leaf water potential compared to variety Nakdongbyeo. This result along with visual observation on leaf rolling and drying during the experimental period indicated poor physiological performance of this transgenic rice line. Further studies on metabolic status of stress-induced trehalose, along with study on physiological response of this transgenic rice line during drought stress would shed more light on overall physiological performance of this transgenic rice line.

Re-ranking the Results from Two Image Retrieval System in Cooperative Manner (두 영상검색 시스템의 협력적 이용을 통한 재순위화)

  • Hwang, Joong-Won;Kim, Hyunwoo;Kim, Junmo
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.1
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    • pp.7-15
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    • 2014
  • Image retrieval has become a huge part of computer vision and data mining. Although commercial image retrieval systems such as Google show great performances, the improvement on the performances are constantly on demand because of the rapid growth of data on web space. To satisfy the demand, many re-ranking methods, which enhance the performances by reordering retrieved results with independent algorithms, has been proposed. Conventional re-ranking algorithms are based on the assumption that visual patterns are not used on initial image retrieval stage. However, image search engines in present have begun to use the visual and the assumption is required to be reconsidered. Also, though it is possible to suspect that integration of multiple retrieval systems can improve the overall performance, the research on the topic has not been done sufficiently. In this paper, we made the condition that other manner than cooperation cannot improve the ranking result. We evaluate the algorithm on toy model and show that propose module can improve the retrieval results.