• 제목/요약/키워드: two-phase culture

검색결과 197건 처리시간 0.028초

항균활성이 높은 젖산균에 의한 냉면용 동치미액의 속성제조 (Rapid Preparation of Dongchimi-Juice for Naengmyon by Lactic Acid Bacteria Having High Antibacterial Activity)

  • 박상희
    • 한국식품영양학회지
    • /
    • 제12권1호
    • /
    • pp.77-84
    • /
    • 1999
  • The purpose of this study is to establish a rapid preparation method of Dongchimi-juice having favor-able flavor and high antibacterial activity against undesirable bacteria in Naengmyon-broth by using high antibacterial strains of lactic acid bacteria Lactobacillus homohiochii B21 and leuconostoc mesenteroid-es subsp. mesenteroides C16 as Dongchimi starter. When the two strains of lactic acid bacteria were used as starter mixed culture was better than single culture in acid production and antibacterial activity. When starter was not inoculated in Dongchimi fermentation the numbers of Gram negatives and colifor-ms were remarkably increased in early phase and antibacterial activity could scarcely be detected. But when starter was inoculated the numbers of Gram negatives and coliforms were sharply decreased from early phase and antibacterial ctivity was high. When Dongchimi was made with heat sterilized mat-erials and starter there were no Gram negatives and coliforms and antibacterial activity was high. The antibacterial activity of starter inoculated Dongchimi was maximum in 2 days of fermentation at 2$0^{\circ}C$ and was scarcely detected in six days. In consideration of coliform counts antibacterial activity and the flavor of Dongchimi the preparation method in which all materials were heat treated at 8$0^{\circ}C$ for 15 min-utes and inoculated with mixed starter of the two strains and fermented for 2 days at 2$0^{\circ}C$ was thoug-ht to be good.

  • PDF

Cochlodinium polykrikoides(Dinophyceae)에서 분비되는 유기물질의 특성 (Characteristics of Organic Substances Produced from Cochlodiniumpolykrikoides (Dinophyceae))

  • 강양순;권정노;안경호
    • ALGAE
    • /
    • 제21권2호
    • /
    • pp.253-259
    • /
    • 2006
  • Organic substances are released from phytoplankton cells during all phases of growth. The type and amounts of organic substance excreted and the effects of nutrient limitation are often highly species-specific. Dinoflagellate, Cochlodinium polykrikoides grown in batch culture produced an exopolysaccharide. Exopolysaccharide and intracellular polysaccharide concentrations increased as C. polykrikoides cultures progressed from exponential phase, through stationary phase, to declining phase. In the exponential phase, the concentration of exopolysaccharide was relatively low, but in the stationary phase, it showed a rapid increase which seemed to coincide with the depletion of nitrate from the medium. Of the 20 amino acids analyzed, proline dominated in the organic matter of all cultures ranging from 48.2 to 79.9 nmol L–1, and constituting the 20-90% of total amino acids, and followed by histamine varying from 0.7 to 47.5 nmol L–1. Leucine and cysteine were also abundant in the stationary phase. The release rates of exopolysaccharide and intracellualr polysaccharide were higher the end of stationary phase than in the exponential phase. Exopolysaccharide concentration per cell was more than two times higher during the end of stationary phase than that in exponential phase. C. polykrikoides produced extracellular polysaccharide at a rate of 47.04 pg cell–1 day–1.

Aspergllus oryza와 그 변이주의 연적배양에 의한 amylase 생성에 관한 연구 (Amylase Production by Continuous Cultures of Aspergillus oryzae and its Mutants)

  • Han, Hong-Eui
    • 미생물학회지
    • /
    • 제15권2호
    • /
    • pp.63-76
    • /
    • 1977
  • Irradiation with high doses of gamma rays induced the reduction of mycelial weight and anaylase activity, and increased relative amylase activity in surface cultures. Biphase in growth curves was shown in aeration-agitation cultures but the behavior of the first phase of growth could be eliminated by replacing the amylasehydrolysed starch substrates, so that enzyme production was shortened ca. 40 hours and relative amylase activity was increased about 3 times higher before onset of autolysis. In the effect of gibberellin on amylase production, the positive stimulation was appeared to only surface culturs of the liquid medium and the negative effect to shake-cultures in a mutant. Trials of various continuous culture were resulted not only the approalch to the value of amylase activity in surface cultures of liquid medium, but also higher productivity than in batch cultures. The culture-degeneration was observed in two-stage continuous culture, but did not appear in continuous elevation culture.

  • PDF

Introduction of the European Peep-box and Development of Visual Culture in the 18th Century Japan

  • LEE, Sang-Myon
    • 비교문화연구
    • /
    • 제36권
    • /
    • pp.97-122
    • /
    • 2014
  • During the Edo-period [江戶時代 1603-1867], Japan accepted the modern western science and culture while trading with Holland since 1609, and also through the influx of optical instruments in the $18^{th}$ century the culture of viewing pictures began to be developed. Especially, the peep-boxes and their pictures had been imported from China and Holland since the mid 1750s when they were flourished. The peep-box was rapidly and widely spread. Soon after, the peep-boxes and pictures had begun to be produced in Japan (megane [眼鏡] and megane-e [眼鏡繪]) since 1770s when the early visual culture settled down in Kyoto and Tokyo etc. The visual culture developed with the peep-box contains two remarkable factors in the cultural history of the $18^{th}$ century Japan. First, the peep-boxes became the popular device of visual entertainment, and opened the first phase of the modern visual culture before the advent of photography and cinema in the mid and end of the $19^{th}$ century. Secondly, the peep-box played a role of an educative media as a 'window to the unknown world' in the $18^{th}$ century Japan, by showing various pictures of many European cities. Through the peep-box pictures the 'western images' were spread and knowledges of Japanese about the west increased, although they were recognized just as 'Holland's images' without differentiation in each country.

문화적 차이를 중심으로 본 사회적 로봇 디자인을 위한 인간 동작의 분석 (Human Motion Analysis for Designing Social Robots Based on Cultural Difference)

  • 양의정;황원일
    • 대한산업공학회지
    • /
    • 제38권2호
    • /
    • pp.133-143
    • /
    • 2012
  • The study on social robots has been actively conducted in the robot research community. In the area of robot design, however, there are few studies regarding robot motions that are one of the methods for interaction between humans and robots. This is a preliminary study to find preferred human motions that can be applied to social robots. We conducted a two-phased empirical study about preferred human motions. In the first phase, four representative human motions, such as 'greeting', 'I don't know', 'positive answer', and 'giving', were captured through 28 body makers and video recording. 10 young and 6 elderly Singaporeans participated in the motion capture process. In the second phase, the communication efficiency, emotion, and satisfaction of the human motions recorded in the first phase were measured by a questionnaire and 31 young Koreans, 35 young Singaporeans participated to investigate cultural differences. We drew the conclusion that motions used in the same culture are efficient in communication and also give friendliness and satisfaction. In addition, regardless of user's culture, young people's motions and female motions were preferred in terms of communication efficiency, emotional aspect, satisfaction.

Case Study: Oriental Brewery, Co. Ltd. Vitalizing Cass Brand through Brand Portfolio Strategy

  • Hong, Sung Tai;Son, Young Seok;Na, Woon Bong
    • Asia Marketing Journal
    • /
    • 제15권4호
    • /
    • pp.187-200
    • /
    • 2014
  • The case study of OB shows dramatic market dynamics between leader brand vs. follower brand similar to Kirin vs. Asahi in Japan for two decades. Almost 20yrs ago, the brand status of OB was dramatically fallen because of the environmental pollution of subsidiary company and harsh competition of rivalry brand. But OB made a ground change in its brand strategy. OB departed from the pride in its past to bet on the new. OB decided to vitalize Cass brand through brand portfolio strategy. They deployed 3 phase articulated marketing plans; Phase I, Acquisition of Cass brand through M&A and strategic segmentation/targeting (1993-2005), Phase 2 - Mega Brand Strategy through Line Extension(2006-2009), Phase 3 - Experiential Marketing focused on Young Culture (2010- present). Finally, OB restored not only brand reputation of Cass and other brands but dominant market position in beer market. Now Cass has been growing rapidly in the last 20 years achieving 50% M/S. The three phases shows the typical successful process of brand management and revitalization adopting brand concept management and S-T-P strategy of manufacturing company.

  • PDF

Highly Branched Glucooligosaccharide and Mannitol Production by Mixed Cultrue Fermentation of Leuconostoc mesenteroides and Lipomyces starkeyi

  • Yoo, Sun-Kyun;Kim, Do-Man;Day, Donal F.
    • Journal of Microbiology and Biotechnology
    • /
    • 제11권4호
    • /
    • pp.700-703
    • /
    • 2001
  • The influence of process conditions on highly branched glucooligosaccharides production by mixed culture of Leuconostoc mesenteroides ATCC 13146 and Lipomyces starkeyi ATCC 74054 was studied. We divided the batch culture fermentations into two groups according to inoculation method. One-point inoculation was performed by coinoculation of L. mesenteroides and L. starkeyi at the ration of 10 to 1, and two-point inoculation by L. mesenteroides inoculation first and L. starkeyi inoculation after L. mesenteroides grew to the end of the log phase of growth. Two-point inoculation improved the yield of oligosaccharide by 1.5 to 20 fold more than one-point inoculation. In this process, the highest yield of oligosaccharides (48% of theoretical yield) and productivity (0.85 g/l/h) were obtained with starch as an initial substrate for L. starkeyi growth. The estimated composition of the end product consisted of 31.5% oligosaccharides, 17.6% dextran, and 46.5% mannitol.

  • PDF

Factors Indicating Culture Status During Cultivation of Spirulina (Arthrospira) platensis

  • Kim, Choong-Jae;Jung, Yun-Ho;Oh, Hee-Mock
    • Journal of Microbiology
    • /
    • 제45권2호
    • /
    • pp.122-127
    • /
    • 2007
  • Factors indicating culture status of two Spirulina platensis strains were monitored in a batch mode cultivation for 36 days. Changing mode in all factors showed a common turning point, indicating shift of cell or culture status. Mean biomass productivity was highly sustained until day 22, chlorophyll a concentration peaked on day 22, pH value was > 12 on day 22, coil number was abruptly shortened on day 22, and floating activity was sustained at greater than 79% after day 22, indicating that day 22 is a criterion reflecting phase-transfer in cell physiology in a batch culture system. Many of these changes may have been caused by increased pH, suggesting that pH control is essential for mass production of S. platensis. Fluctuations in floating activity were likely induced by the number of cellular gas vacuoles. Consequently, coil number per trichome and floating activity of S. platensis could readily act as simple indicators for determination of culture status or harvesting time of cells.

A STUDY ON CHONDROGENIC POTENTIAL IN MANDIBULAR AND LIMB BUD MESENCHYMAL CELLS OF HUMAN EMBRYOS : A POSSIBLE ROLE OF PROTEIN KINASE C

  • Kook, Yoon-Ah;Kim, Eun-Cheol;Kim, Sang-Cheol
    • 대한치과교정학회지
    • /
    • 제26권6호
    • /
    • pp.667-676
    • /
    • 1996
  • We have examined the in vitro stage-related chondrogenic potential of human mandibular and limb bud mesenchyme cells using micromass culture. Our results indicate that limb bud mesenchyme cells as early as stage 16 by Carnegie system (37 days), well before the initiation of in vivo chondrogenesis, have chondrogenic potential which is expressed in micromass culture. These results are correlated with stage-related chondrogenic potential of human limb bud in vivo as a result of Alcian blue staining. The proliferation of chondrogenic cells increased in the first 3 days after culture and then decreased. These results were correlated with the cell cycle analysis of which the number of $G_0^1/G_1$ phase increased markedly after 3 days of culture, while the percentage of cells in S phase was decreased. On the other hand, it was rarely differentiated in the mandible. We examined the effects of two PKC modulators such as phorbol 12-myristate 13-acetate (PMA), a potent activator of PKC, and staurosporine (STSN), an inhibitor of PKC. PMA inhibited the chondrogenesis, whereas STSN promoted the chondrogenesis in a dose dependent manner. In addition, PMA exerted no inhibitory effect when the cells were pretreated for 24 h with STSN, implying that the chondrogenic events might be settled at an early step in vitro and FKC may act as a negative modulator. Collectively, these results demonstrate, for the first time, the stage-related chondrogenic potential of human mandibular and limb bud mesenchyme cells and the role of PKC during chondrogenesis in vitro & in vivo.

  • PDF

Optimization of Culture Conditions for Production of Pneumococcal Capsular Polysaccharide Type I

  • Kim, Su-Nam;Min, Kwan-Ki;Kim, Seung-Hwan;Choi, In-Hwa;Lee, Suhk-Hyung;Pyo, Suhk-Noung;Rhee, Dong-Kwon
    • Journal of Microbiology
    • /
    • 제34권2호
    • /
    • pp.179-183
    • /
    • 1996
  • Streptoccus Pneumoniae (pneumococcus), the most common cause of bacterial pneumonia, has an ample polysaccharide (PS) capsule that is highly antigenic and is the source of PS vaccine. This investigation was undertaken to optimize the culture conditions for the production of capsulard PS by type 1 pneumococcus. Among several culture media, brain heart infusion (BHI) and Casitone based media were found to support luxuriant growth of pneumococcus type 1 at the same level. Because BHI medium is rather expensive and more complex than the Casitone based media, the Casitone based media was uwed to study optimization of the culture condition. The phase of growth which accomodated maximum PS production was logarithmic phase. Concentrations of glucose greater than 0.2% did not ehnahce growth or PS production. Substitution of netrogen sources with other resources or supplementation of various concentrations of metal ion (with the exception of calcium ion) had adverse affects on growth and PS production. On the other hand, low level aeration was beneficial for increased PS production. Addition of 3 mg/1 concentration of methionine, phenylalanine, and threonine were found to enhance growth and PS production. The synerigistic effect of all the favorable conditions observed in pneumococcal growth assays provided a two-fold cummulative increase in capsular PS production.

  • PDF