• Title/Summary/Keyword: Initial growth

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Physiological Characterization of Lactobacillus sp. JK-8 Isolated from Shrimp Aquaculture Pond (새우양식장에서 분리한 Lactobacillus sp. JK-8의 생리적 특성)

  • Chun Jae-Woo;Ma Chae-Woo;Oh Kye-Heon
    • Korean Journal of Microbiology
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    • v.41 no.1
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    • pp.18-23
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    • 2005
  • The purpose of this work was to investigate the physiological characteristics of Lactobacillus sp. JK-8 isolated from a shrimp aquaculture pond. The strain JK-8 was grown on MRS media, and morphological and physiological characteristics of the strain were examined. The bacterium was identified as a strain of the genus Lactobacillus on the basis of BIOLOG test. Strain JK-8 produced both lactic acid and acetic acid, which were responsible for the pH decrease during growth. Concentrations of lactic acid and acetic acid increased to 192.8 mM and 43.6 mM, respectively, and the initial pH 7.0 of the cultures decreased to 3.8 at the end of incubaction. The bacteriocidal effect against eight target bacteria was examined with 5-fold concentrated culture supernatants. All bacteria tested in this work were completely killed within 3 hrs after treatment with the culture supernatant. The bacteriocidal effects were clearly observed, only when the pH of the culture supernatants were not adjusted. HPLC was used to reslove lactic acid and acetic acid in the culture solution, and GC-MS was used to verify the metabolites.

Cultural and Physiological Conditions for T-2 Toxin Production by Fusarium sp. (Fusarium 균주의 배양 조건 및 생리적 조건에 따른 T-2 toxin의 생성 조건)

  • 홍성희;양규환
    • Korean Journal of Microbiology
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    • v.36 no.2
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    • pp.91-96
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    • 2000
  • The cultural and physiological conditions for the T-2 toxin [4,15-diacetoxy-8-(3-mety1butyloxy)-12,13- epoxy-trichothec-9-en-3-01, $C_{24}H_{30}O_9$] production by Fusarium spp. were studied. Thin layer chromatography (TLC) assay and the microbiological assay uslng Rhodotomla rubra were used to quantitate tbe T- 2 toxin. Among the four strains of Fusarium spp., F tn'cinctum NRRL 3299 was best for T-2 toxin production. In solid culture, white com grit medium was best for T-2 toxm production. Temperature played a critical role in the production of T-2 toxin. T-2 toxin production was favored by long duration of low-temperature incubation. The growth and toxin production were relatively high on galactose, fructose, glucose, and sucrose media, when each was used as a sole carbon source, and relatively low on sorbitol, glycerol, and lactose media. For nitrogen sources, $NH_4^(+) and NO_3^{-}were used well as a sole nitrogen source, but $NO_2^-$ was not used. Initial pH and speed of shaker also affected the production of T-2 toxin. From temperature shifting experiment, it is clear that T-2 toxin metabolic pathway is regulated by temperature-dependent enzyme depression or enzyme induction system.

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Studies on Marine Heterotrophic Protists in Masan Bay, Korea (마산만에서 부유원생동물의 연구)

  • Lee, Won-Je;Shin, Kyung-Soon;Lee, Jae-Do
    • Ocean and Polar Research
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    • v.29 no.4
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    • pp.401-410
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    • 2007
  • In Korea the study of marine heterotrophic protists started in the late 1980s, and since the early 1990s many studies have been conducted in various marine environments. In this article, studies on the distribution and abundance of protists and the biotic interactions(bacteria-protists, phytoplankton-protists) conducted in Korean coastal waters are reviewed, and a field study is reported and discussed. The field study in Masan Bay was carried out from February 2004 to November 2005 at seven selected stations representative of the bay. During the study, the mean abundance of heterotrophic bacteria and the mean concentration of chlorophyll-a were $2.1{\times}10^6\;cells\;mL^{-1}$ and $9.8{\mu}g\;L^{-1}$, respectively. Heterotrophic protists consisted of heterotrophic dinoflagellates, heterotrophic nanoflagellates(excluding dinoflagellates) and ciliates, and their abundances were means of $7.9{\times}10^4\;cells\;L^{-1}$, $1.2[\times}10^3\;cells\;mL^{-1}$, and $4.0{\times}10^4\;cells\;L^{-1}$, respectively. Generally, the chlorophyll-a concentra+CZ14tions and the abundances of heterotrophic bacteria and protists were higher in the inner zone of the bay, where there are high concentrations of organic matters, than in the middle and outer zones. Using the grazing rates of heterotrophic nanoflagellates on bacteria previously reported in this area, it can be calculated that about 69% of bacterial producton was removed by HNF grazing activity. About 24% of initial chlorophyll-a concentration was removed by microzooplankton grazing activity. In conclusion, this study suggests that in Masan Bay heterotrophic protists control the growth of bacteria and phytoplankton, and heterotrophic protists represent an important link of bacterial & microalgal biomass to higher trophic levels.

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.

Cultural Characteristics of Psychrotrophic Lactic Acid Bacteria Isolated from Kimchi (김치에서 분리한 저온성 젖산균의 배양특성)

  • So, Myung-Hwan;Kim, Young-Bae
    • Korean Journal of Food Science and Technology
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    • v.27 no.4
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    • pp.506-515
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    • 1995
  • The cultural characteristics of 60 strains of psychrotrophic lactic acid bacteria which were isolated from kimchi, a Korean traditional fermented vegetable food, and identified as Leuconostoc mesenteroides subsp. mesenteroides, Leu. mesenteroides subsp. dextranicum, Leu. paramesenteroides, Leu. lactis, Lactobacillus bavaricus and Lac. homohiochii were tested. All strains grew at $5^{\circ}C,\;10^{\circ}C\;and\;37^{\circ}C$ in tomato glucose broth, but not at $45^{\circ}C$. The optimum growth temperature of Leu. mesenteroides and Lactobacillus sp. were $33{\sim}34^{\circ}C\;and\;34{\sim}36^{\circ}C$, respectively. All strains of Leu. mesenteroides and Lactobacillus sp. grew at 4.8 and 4.2 of initial pH, but not at 4.0. The final pH of Leu. mesenteroides and Lactobacillus sp. in glucose broth were $3.84{\sim}4.10\;and\;3.82{\sim}3.99$, respectively. None of the 60 strains clotted milk nor reduced litmus in litmus milk. All strains of Leu. mesenteroides and Lactobacillus sp. grew in tomato glucose broth containing 7% ethanol or 6.5% NaCl, but not in the broth containing 15% ethanol or 10% NaCl. All strains grew in tomato glucose broth containing 40% bile juice and survived in the artificial gastric juice of pH 3.5. Furthermore, all strains of Leu. mesenteroides survived in the artificial gastric juice of pH 3.0. Since many strains of lactic acid bacteria tested in this study showed differences in several physiological characteristics from those described in Bergey's Manual of Systematic Bacteriology, it was considered that further tests would be necessary to clarify their positions in taxonomic system.

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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.

Improvement of Antioxidative Activity by Enzyme Treatment and Lactic Acid Bacteria Cultivation in Black Garlic (효소 처리와 유산균 배양에 의한 흑마늘의 항산화 활성 향상)

  • Chae, Hee-Jeong;Park, Dong-Il;Lee, Sung-Chul;Oh, Chul-Hwan;Oh, Nam-Soon;Kim, Dong-Chung;Won, Sun-Im;In, Man-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.5
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    • pp.660-664
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    • 2011
  • We investigated the improvement of the antioxidative activity of black garlic with enzymatic treatment and lactic acid bacteria cultivation conditions. Celluclast, a commercially-available polysaccharide hydrolyase, was selected to obtain high total polyphenol content in a black garlic suspension. A lactic acid bacterial strain showing fast growth and high acid production in a black garlic suspension was isolated from Kimchi. This strain was identified as Lactobacillus pentosus 310-7. Enzymatically hydrolyzed black garlic was fermented using the L. pentosus 310-7 strain at $30^{\circ}C$ for 15 hr. The pH and titratable acidity achieved were 4.24 and 0.35%, respectively, after 15 hr fermentation. The viable cell population of L. pentosus 310-7 slowly increased to 7.54 log CFU/g. The polyphenolic compound content, known antioxidants, in black garlic was enhanced with Celluclast treatment and L. pentosus 310-7 cultivation. Total polyphenolic compounds were increased to approximately 60% of the initial concentration, and electron donating ability was also improved, from 39.8 to 65.9%.

An Ethnographic Study on CosPlay Group in Korea II - Analysis on CosPlay Culture in Korea and Japan - (한국 코스프레 집단의 문화기술지적 연구 II - 한국과 일본의 코스프레 문화에 대한 비교 분석 -)

  • Koh, Ae-Ran;Shin, Mi-Ran
    • The Research Journal of the Costume Culture
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    • v.14 no.1
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    • pp.1-15
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    • 2006
  • This study examines the social meaning of the CosPlay, the growth potential of CosPlay culture and its effect on the related industry through the perspectives and language of the youths who enjoy CosPlay, based on the ethnographic research. Also, this study presents a comparative description of Korea and Japan CosPlay culture by the ethnographic methodology whose purpose is to define relationship of cause and effect with phenomenon. For further step, this study plans to emphasize the need to link culture, clothes and related industry in order to create a cultural environment where diversity co-exists. CosPlay is the mania culture of Japan that emulated the Halloween party of the West and that developed the party into a unique form. In Korea, this practice was accepted for the first time among a handful of youths, starting from the 1990s, after which, it was introduced to the masses while holding CosPlay related events. While CosPlay is succeeded as an industry in Japan, CosPlay in Korea is considered childish play due to the Korean culture of considering cartoon as a childish and low class genre which is enjoyed by youths. CosPlay in Korea faces the following changes: aging of the members who comprised the CosPlay culture at the initial stage; population increase, centered on middle and high school students; interest of the government and the businesses that wish to produce economic wealth by organizing CosPlay events into events for youths; and changes in the environment that comprised the surrounding of the CosPlay culture. CosPlay is an honest play that demonstrates one's effort on the stage through performance. Moreover, most of the middle and high school students who comprise the CosPlay culture demonstrate similar characteristics as mania type of people when it came to the reason that they enjoy CosPlay. However, they did not consider CosPlay culture as an important aspect of their lives. Instead, most of them said that they participate to relieve stress. Thus, they have the potential to move onto another form of youth culture that may appear more attractive to them. To them, it is not the CosPlay culture that is important, but the fact that CosPlay provides a forum where they can freely engage in play.

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Effects of Demineralized Bone Particle Loaded Poly(lactic-co-glycolic acid) Scaffolds on the Attachment and Proliferation of Costal Cartilage Cells (탈미네랄화된 골분/PLGA 지지체에서 늑연골 세포의 부착과 성장에 미치는 영향)

  • Cho, Sun Ah;Song, Jeong Eun;Kim, Kyoung Hee;Ko, Hyun Ah;Lee, Dongwon;Kwon, Soon Yong;Chung, Jin Wha;Khang, Gilson
    • Polymer(Korea)
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    • v.37 no.5
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    • pp.632-637
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    • 2013
  • It has been widely accepted that costal cartilage cells (CCs) have more excellent initial proliferation capacity than articular cartilage cells as well as the easiness for isolation and collection. This study demonstrated that CCs might be one of the substitutes for articular cartilage cells by tissue engineered cartilage. Poly(lactic-co-glycolic acid) (PLGA) has been extensively tested and used as scaffold material but it was limited by the low attachment of cells and the induction of inflammatory cells. Base on previous our studies, we confirmed demineralized bone particle (DBP) had the power of the reduction of inflammatory reaction and the stimulation proliferation of cells. We fabricated PLGA scaffold loaded with 10, 20, 40 and 80 wt% DBP and then tested the possibility of the regeneration of cartilage using CCs. Assays of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and scanning electron microscope (SEM) carried out to evaluate the attachment and proliferation of CCs in DBP/PLGA scaffolds. Glycosaminoglycan (sGAG) and collagen contents assay were conducted to confirm the effects of DBP on formation of extracellular matrix. This study demonstrated that DBP/PLGA scaffolds showed significant positive effects on cell growth and proliferation due to the vitality of DBP as well as the possibility of the application of CCs for tissue engineered cartilage.

Amylase activity and characterization of Bacillus subtilis CBD2 isolated from Doenjang (된장으로부터 분리된 Bacillus subtilis CBD2의 생육특성 및 amylase 활성)

  • Yang, Su-Jin;Lee, Dae-Hoon;Park, Hye-Mi;Jung, Hee Kyoung;Park, Chang-Su;Hong, Joo-Heon
    • Food Science and Preservation
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    • v.21 no.2
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    • pp.286-293
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    • 2014
  • In this study, one GRAS strain was screened from doenjang, a traditional Korean fermented food, as a microorganism producing amylase due to the formation of a clear zone on the medium including soluble starch. From the analysis of the gene sequence of 16S ribosomal RNA, the strain was identified as Bacillus subtilis and was therefore named Bacillus subtilis CBD2. When the nutrient broth medium was prepared with 3% NaCl, 5% glucose, and the initial medium pH 7.0, the B. subtilis CBD2 showed maximum growth. Among soluble starch, corn starch, maize amylopectin, and wheat starch, soluble starch was the most effective carbon source in the production of amylase by B. subtilis CBD2. The amylase from B. subtilis CBD2 showed the highest activities at pH 8.0 and $50^{\circ}C$, and corn starch was the most proper substrate for the enzyme activity. When corn starch was used as a substrate, the production of sugars through enzyme activity increased for 24 h, and then the enzyme activity became constant.