• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.231-238
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• 2006

The physical properties of seven perlites different in particle size distribution were investigated to develop perlite bag culture in Korea. Particle sizes of 1.0-2.8mm and larger than 2.8 mm were rather evenly distributed in S-1 (1.2-5 mm), S-2 (0.15-5 mm) and S-5 (parat No.1). Larger particles were less in S-3 (1-3 mm), S-4 (Parat No.2), S-6 (OTAVI) and S-7 (Agroperl B-3). S-4, S-6 and S-7 contained lots of particles less than 1 mm in size. Total porosity was similar among substrates with the value of $59{\sim}62%$. Container capacity was between 35-40% regardless of substrates except in S-2 with 27.7%. Water content, which was about 60% at 0 kPa, was decreased sharply at 4.90 kPa regardless of substrates, which meant the easily available water was plenty in any kind of perlite tested. Substrates, S-1, S-2 and S-3 with different particle size distribution, were investigated to evaluate for perlite bag culture. Six tomatoes (Licopersicon esculentum Mill. cv. Rokkusanmaru) were planted in a perlite bag of 40 liters with the dimension of 120cm in length and 34cm in width. The amount of nutrient solution supplied and its drainage dependent on daily integrated radiation didn't show any regular trend during the growth. Roots in the bag were distributed evenly in S-1 and S-2 than in S-3. Plant grown in S-1 showed the highest total and marketable yield of 8,628 and 7,759 kg/10a, respectively. The number of small size fruits and malformed fruits were more in S-3. Consequently, S-1 with the particle size distribution of 1.2-5 mm is suggested as desirable substrate for perlite bag culture.

• Journal of Korea Entertainment Industry Association
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• v.15 no.3
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• pp.75-88
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• 2021

The film won the Golden Palm Award at the Cannes Film Festival, and received the Academy Award for a non-English-speaking film in February 2020, respectively. It has received a monumental evaluation in the world film history. Overall, this film is about class conflict, and critics evaluate the theme of the film as "badly twisted class gap" and "anger from class." The film expresses an intrinsic conflict embodied in culture as a "tragedy in which no bad person appears," rather than the dichotomous composition of the classical class struggle from Marxism. In other words, this can be seen as expressing the substrated class relationship of the modern society that Pierre Bourdieu had argued. This film has been focused as a controversial target under Korea society with excess of ideology. Politics used to adopt the keyword, 'parasite', for political disputes not only in culture contents world. Paradoxically socialism China did not allow to release film 'Parasite.' On the other hand, Lee O-Yong argues that the movie "Parasite" does not look at social phenomena through a dichotomous perspective, but is viewed through a "double perspective" and evaluates that it does not lose eyes looking at humans through tension. This view is based upon 'Vital Capitalism'. Lee. O-Yong looks at the movie "Parasite" from the perspective of "Vital Capitalism". The theory of Vital Capitalism does not seek to find the root of historical development in class struggle conflicts, but rather figuring out history and society pays attention onto the intrinsic characteristics of life, Topophilia, Neophilia, and Biophilia. Lee Eo-ryeong argues that the development of civilization theory evolved from the stage of Hobbes' Darwinism or predatism to the stage of host vs. parasite of Michel Serres, and onto the stage of Margulis's 'Win-Win (inter-dependence)'. In this paper, after overview of vital capital concept and preceeding research, re-interpretations were tried onto scenes based upon fields from habitus, culture capital. This exploration looks for a alternative for excess of ideology in Korea society.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.263-270
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• 2015

A bacterial strain producing extracellular mannanases was isolated from soil of chestnut tree farm located in Gongju city of Korea by enrichment culture using Avicel as a carbon source. 16S rDNA sequence of the isolate YB-43 was highly homologous to those of genus Cellulosimicrobium strains with sequence similarities of above 99.6%. Mannanase productivity was significantly increased when the Cellulosimicrobium sp. YB-43 was grown in the presence of locust bean gum (LBG) or konjac. The mannanases were partially purified to be mannanase A (ManA) and mannanase C (ManC) by DEAE-Sepharose column and Q-Sepharose column chromatography from the culture filtrate of Cellulosimicrobium sp. YB-43 grown in LB medium supplemented with 0.7% LBG for 24 h. The partially purified ManA showed the highest activity at $55^{\circ}C$ and pH 6.5, while ManC activity was optimal at $65^{\circ}C$ and pH 7.5. ManA was stable up to $40^{\circ}C$ for 1 h, but ManC activity decreased significantly even after 1 h at $20^{\circ}C$. ManA and ManC showed difference from each other according to their substrate specificities and predominant products resulting from the mannanase hydrolysis for mannooligosaccharides. As a result, Cellulosimicrobium sp. YB-43 was found to produce two different kinds of mannanases.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.679-684
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• 2005

The objective of this study was investigate the characteristic of biosurfactant produced from the iso-lated strain. The strain was isolated from soli samples of Duck-Yu Mountain and it was identified as Bacillus atrophaeus DYL-130 by 16S rDNA and gyrA gene nucleotide sequence analysis. The surface ten-sion of culture filtrate of Bacillus atrophaeus DYL-130 decreased to 28 mN/m and its biosurfactant con-centration was determined by diluting the culture filtrate until the critical micelle concentration (CMC). The emulsifying activity and stability of crude biosurfactant was measured by using water-immiscible hydrocarbons and oils as substrate. The biosurfactant was purified by affinity chromatography and the surface activity of purified biosurfactant was measured by drop-collapsing method and it could be effectively emulsify toluene.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.2
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• pp.143-149
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• 2005

Objects : With the advancement of tissue engineering techniques, the effort to develop bioartificial mucosa have been actively delivered. The problem we met with this technique is the lack of mechanical strength between kerationocyte layer and dermal layer, where in the normal skin and mucosa, they are tightly bound with rete ridge structure. The purpose of this study is to understand the 2D and 3D structure of rete ridge of mucosa and skin paddle for rendering more biomimetic structure to the artificial mucosa. Materials and Methods : Oral mucosa and skin from the patients who received the oral surgery and maxillofacial reconstruction were harvested. The epidermis was separated from the dermis after treating with dispase for 12-16 hours. H&E staining was performed for 2D(dimensional) structure study and confocal LASER and SEM study were performed for 3D structure. Mean height(Sc) and arithmetic mean deviation(Sa) of all surface height were calculated. Results : The average height of rete ridge of skin flap was between $67.14{\mu}m$ and $194.55{\mu}m$. That of oral mucosa was between $146.26{\mu}m$ and $167.51{\mu}m$. Pressure bearing area and attached gingiva of oral mucosa showed deeper rete ridges. Conclusion : To obtain the adequate strength of artificially cultured keratinocyte skin and mucosa flap, it is necessary to imitate the original skin and mucosa structure, especially rete ridge. Through this study, 2D and 3D rete ridge structure of normal mucosa and skin was obtained. These results can be used as basis for substrate morphology for keratinocytes culture.

• KSBB Journal
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• v.14 no.5
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• pp.539-542
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• 1999

For the mass production of DFAIII and for the development of techniques of separation and purification of it, the methods of production of DFAIII and its recovery was investigated by fermentation with the strain of Arthrobacter ureafaciens KCTC 3387 and by enzyme reaction. In the first method, DFAIII was produced by fermentation with the strain of Arthrobacter ureafaciens KCTC 3387 and recovered from culture supernatant with silica gel gy filtration, in the second method, it was produced by enzyme reaction and recoverd with the same method of the first, and in third method it was produced by fermentation and recovered by addition of ethanol to the culture supernatnat.Against 25g/L of initial concentration of inulin, 1.57, 4.40, 0.34 g/L of powder of DFAIII was recovered respectively and the rate of recovery was 6.3, 17.6 1.4% and the purity was estimated at 81, 97, 87% respectively. For the production of DFAIII and its recovery, enzyme reaction method was the highest in the rate of recovery and its purity. By fermentation method, DFAIII was produced with 50% fo initial concentration of substrate but th rate of recovery was lower than enzyme reaction method and purity was lowest among the three methods. Ethanol pricipitation method showed the lowest rate of recovery.

• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.21-26
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• 2011

Differences among cultivars, conditions of nutrient solution, nursing materials, and soilless culture systems were investigated to select suitable cultivar and cultivation methods for stable production of summer spinach in the highlands. The 'Quinto' spinach showed the earliest growth and highest yield. For yield increase of summer spinach, optimal solution pH was 6.0, EC was $2.0dS{\cdot}m^{-1}$, and $NH_4-N$ ratio of nutrient solution was 30 percent Stand rate of spinach in nursing seedlings, at 200-cell-tray filled with mixed nursing soil (peat : perlite = 7 : 3), was higher than those grown in urethane sponge and rock-wool plug. Yield was also 18 to 24 percent higher than those in rock-wool plug and urethane sponge. Plant length and yield of spinach in mixed substrate (peat : perlite = 7 : 3) filled nutrient film technique (MSNFT) system were longer of 18 percent, and higher of 9 percent than those in deep flow technique (DFT) system, respectively. However, changes of root zone temperature, pH and EC showed similar pattern with DFT. Therefore, growing 'Quinto' cultivar at 6.0 of pH, $2.0dS{\cdot}m^{-1}$ of EC, 30 percent of $NH_4-N$ ratio, at 200-cell-tray filled with mixed nursing soil, and MSNFT cultivation system, was the best for production of summer spinach in the highlands.

• Microbiology and Biotechnology Letters
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• v.39 no.4
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• pp.357-363
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• 2011

This study focus was primarily the development of liquid starters for Aspergillus oryzae and Aspergillus niger prepared with wheat bran as a low cost culture medium. For the preparation of the liquid media wheat bran was added at rates of 0, 5, 10, 15 and 20% and the Aspergillus sp. strains were then inoculated to these prepared broths. The results indicated that the more that wheat bran was contained in the medium, the more mycelia was produced for A. oryzae and A. niger. The highest enzyme activities were obtained with a 10~15% adding rate of wheat bran for both strains. Changes in the enzyme activities of the liquid starters during various incubation times (0, 24, 48, 72 and 96 hrs), indicated that the highest enzyme activities were seen between 48 and 72 hrs of culture. In addition, a comparative study was carried out on the production of enzymes using wheat as a substrate in nuruk, with liquid starter made from fermented agents according to the same concentrations used with the wheat bran. The pH, acidity, amino acidity, reducing sugar content and enzyme activity (${\alpha}$-amylase, glucoamylase, acidic protease) of wheat nuruk made with liquid starter were compared with those of wheat nuruk made with solid starter. The results suggest that the liquid starter is superior in both cases.

• Applied Biological Chemistry
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• v.18 no.3
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• pp.117-122
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• 1975

In order to utilize the agricultural waste products for animal feeds, studies have been made concerning the production of cellulase of Irpex lacteus and its properties of crude enzyme, and summarized as follows. 1. At the production of cellulase, the culture of wheat bran added with rice bran was more active than any other cultures. 2. The optimum incubation time is 5 days in shaking culture. 3. The optimum condition of reaction in saccharification with CMC were obtained the following results. 1) The optimum pH was within the range of from 3.5 to 4.0 and stable within 3.0 to 6.0. 2) The optimum temperature was $40^{\circ}C$ and thermal stability was below $40^{\circ}C$. 3) The optimum reaction time was 2 hours. 4) The optimum crude enzyme concentration was 50%V/V and substrate concentration 1%.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.225-230
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• 2006

Tomatoes were experimented in perlite bags for various irrigation control methods to elucidate the efficient method for nutrient solution management. The irrigation control methods were for 3 different types such as control by drainage level sensor (PROBE), control by integrated solar radiation (ISR), and control by time clock (Timer). The substrate weight was maintained stably in the proper range in PROBE treatment, regardless of daily solar radiations or growth stages. The bed weights in the treatments of ISR and Timer were changed largely. Growth as well as total yield was the highest in PROBE treatment. There was no difference in soluble solids (Brix %) among the treatments. Consequently, ISR control could be useful only with appropriate timer control and also calibration. Control by drainage level sensor was suggested to be the most satisfactory as irrigation management method.