• Journal of Plant Biotechnology
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• v.36 no.2
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• pp.184-192
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• 2009

The influences of pretreatment medium, the addition of fresh medium, and the size of culture plate on the production of embryos were investigated in isolated microspore culture of hot pepper (Capsicum annuum L.). Among the media used for heat shock pretreatment ($32{\pm}1{^{\circ}C}$), high frequency embryo production was obtained when the sucrosestarvation medium A was used. On the other hand, neither 0.37 M mannitol solution nor NLNS medium supplemented with sucrose was not efficient for embryo production. The addition of culture medium to pretreatment media considerably decreased the embryo production even though embryo development proceeded further. The embryo production was not improved by the addition of fresh medium after 2 or 3 weeks from starting culture. Increase in the size of the culture plate from $3.5{\times}1.0$ cm to $6.0{\times}1.5$ cm improved embryo quality. These results will provide valuable information for developing an efficient microspore culture system of hot pepper for high frequency embryo production.

• KSBB Journal
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• v.6 no.1
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• pp.69-77
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• 1991

When S. fradiae was cultured in S medium, it stavted to produce neomycin in the middle of stationary phase of growth. Antibitoic production is regulated not only by glucose but also by metabolites formed from glucose. A chemically defined minimal salt broth was developen for the study of metabolites activating produition of antibiotic in a neomycin producer. When growth and production or antibiotic in minimal salt broth was examined with a full grown or a vefctativc mycelium, the medium was found not to be good for the growth, but to be good enough for the production of antibiotic with a full grown mycelium. When many carbotlydrates, organic acids, or alcohol were supplmented with instead of glucose in the medium suspcndcn with a full grown mycelium, the amount of antibiotic produced in the medium containing fumaratc was 5 times more than that in the medium with glucose. Further study indicated that the medium is not good also for the growth but good for the production of antibiotic. The antibiotic produced in this medium was identified to be neomycin. The activation of the production of neomycin by fumarate was further confirmed in a complex medium. Fuinarate is suspected to initiate and to activate the biosynthesis of neomycin at the gene level.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.158-161
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• 2004

Scenedesmus spp. were cultured for 51 days in newly developed medium, KEP I (Kim and Ecopeace: initials of corresponding author and environmental company) made with Bacterio-Mineral-Water (3%, v/v) that had been bio-reacted with swine urine medium to 10% (v/v) Bold's Basal medium, and investigated for cancer chemopreventive potential by measuring the induction of quinone reductase (QR), glutathione S-transferase (GST), and reduced glutathione (GSH), and inhibition of cytochrome P450 (CYP) 1A1 activity. The activitives of QR and GST of Scenedesmus spp. cultured in KEP I medium were increased by 3.0-fold and 1.5-fold, respectively. However, Scenedesmus spp. cultured in control medium (CT) increased the activitives of QR and GST by 1.8-fold and 1.3-fold, respectively. Scenedesmus spp. in KEP I medium strongly inhibited CYP 1Al activity. These results show that Scenedesmus spp. in KEP I medium has cancer chemopreventive potential and may be a candidate for further development as a chemopreventive agent.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.231-235
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• 1989

Possibility of using microcarriers for the growth of a transformed human embryonic kidney cell line 293 was investigated. The cell grew well in a static culture such as T-flasks with medium of DME/F12 (3:1) mixture supplemented with 5% FBS, but it was most difficult to make the cells grow on microcarriers mainly due to the low attachment efficiency and poor spreading at initial stage of the culture. Consequently, 30-50% of the cells were lost upon inoculation into microcarrier suspension and significant fraction of the mirrocarrier became bald. The medium supplemented with the concentrated conditioned medium by hepatoma cell line HpG2 supported the active growth of the cells on microcarrier and the cells showed a very healthy and well spreading morphology. It was probable that some spreading and attachment factors of HpG2 conditioned medium were effective for 293 cells.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.2
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• pp.265-270
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• 1989

The present study considers the thermal structure variation in a porous medium caused by changing the most important radiative property of porous medium, absorption coefficient, as well as altering the physical dimension of porous medium and the equivalence ratio of premixed gas mixture. The radiation model was introduced as an unsteady differential form using the two-flux gray radiation model. The role of the conductive heat transfer through both gas phase and porous medium was found to be almost insignificant compared with that of the radiative heat transfer. The reaction zone shifted upstream and the flame thickness decreased as either the geometrical length of porous medium increased or the absorption coefficient decreased.

• The Korean Journal of Food And Nutrition
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• v.6 no.3
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• pp.189-198
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• 1993

This study was carried out to investigate the effect of medium-cooked rice on brewing of yakju which was a traditional rice wine in Korea. The influences of cooking temperature of rice on hydrolysis of rice starch and rice protein were tested, and experimental brewings were done according to the traditional brewing method of Bangmunju in which some medium-cooked rice was used. The results obtained were as follows The hydrolysis of starch and protein in medium-cooked rice at 60~$65^{\circ}C$ was easier than that of full-cooked rice at 80~10$0^{\circ}C$. The amounts of saccharides, total amino acids and extracts In Yakju brewed with the combined use of medium-cooked rice and full-cooked rice were twice as much as those brewed with full-cooked rice only. The results of sensory test of Yakju brewed with the combined use of medium-cooked rice and full-cooked rice were better in taste, color and flavor than those brewed with full-cooked rice only. It was thought that our ancestor's traditional brewing method of Yakju in which medium cooked rice and full-cooked rice were used combinedly was excellent Judging from zymological point of views.

• Korean Journal of Plant Resources
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• v.11
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• pp.40-47
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• 1998

When the leaves, roots and stem segments of seedling of Polygonatum odoratum were cultured on Murashige and Skoog medium with 2.0mg/l BAP, stem segments were the most efficient explants for adventitious shoot inductino. To observe the efficient combination of growth regulators on the adventitious shoot formation , stem segments were cultured on MS medium with various kinds of cytokinins (BAP, kinetin, zeatin). From this experiment, cytokinin treatement was prerequisite for theadventitious shoot formatino,especially BAP was the most effective. Auxin (NAA or IBA) in combination with cyotokinin highly enhanced the adventitious shoot formation. Twenty five percents of explants produced the adventitious shoots on medium with 2.0mg/l BAP solely, while 83% of explants produced the adventitious shoots on medium with 2.0mg/l BAP and 0.1mg/l IBA. Root formationform adventitious shoot was promoted after transfer to 1/2 MS medium supplemented with 0.1mg/l IBA and 0.5mg/l zeatin, thereafter the plantlets with shoots and roots were cultured on 1/2MS medium lacking growth regulators. When the stem segments were cultured to MS medium with 1.0mg/l 2,4 NAA and IBA , yellow and nodulous cali were formed from the stem segments which were developed into adventitious roots. These roots were actively grew after transferred to MS liquid medium lacking growth regulators.

• Journal of Embryo Transfer
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• v.30 no.3
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• pp.171-174
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• 2015

Four pluriparous Korean black goat does were superovulated with FSH and mated with fertile bucks. Anesthetized animals were placed in lateral recumbency, then size 8 Foley catheter was inserted into the uterus through the cervix under the vaginal speculum and the balloon was inflated to fix the catheter in the uterine body. The opposite end of the catheter was connected to a 3-way and a flushing medium was infused into the uterus. Modified Dubecco's PBS with 1% FBS was used as the flushing medium. Four goats were allocated in two groups depending on the type of medium infusion into uterus. Injection group; the flushing medium was injected into uterus and the infused medium was collected by to-and-fro method using a syringe. Gravity-flow group; the flushing medium was allowed to enter the uterus by gravity flow by lifting the medium bottle and drained out of the uterus into a collecting tube. All four goats had catheter inserted through the cervix and uteri flushed successfully. The volume (recovery rate) of recovered medium varied considerably from 87 ml/200 ml (43.5%) to 148 ml/160 ml (92.5%). Nine embryos/ova in total were recovered from Gravity-flow group goats. Although the embryo recovery rate was low, the possibility of a transcervical embryo recovery in Korean black goat had been proven in this preliminary experiment.

• Journal of Animal Science and Technology
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• v.63 no.3
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• pp.603-613
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• 2021

This research improved the growth potential of Bifidobacterium animalis subsp lactis strain JNU306, a commercial medium that is appropriate for large-scale production, in yeast extract, soy peptone, glucose, L-cysteine, and ferrous sulfate. Response surface methodology (RSM) was used to optimize the components of this medium, using a central composite design and subsequent analyses. A second-order polynomial regression model, which was fitted to the data at first, significantly lacked fitness. Thus, through further analyses, the model with linear and quadratic terms plus two-way, three-way, and four-way interactions was selected as the final model. Through this model, the optimized medium composition was found as 2.8791% yeast extract, 2.8030% peptone soy, 0.6196% glucose, 0.2823% L-cysteine, and 0.0055% ferrous sulfate, w/v. This optimized medium ensured that the maximum biomass was no lower than the biomass from the commonly used blood-liver (BL) medium. The application of RSM improved the biomass production of this strain in a more cost-effective way by creating an optimum medium. This result shows that B. animalis subsp lactis JNU306 may be used as a commercial starter culture in manufacturing probiotics, including dairy products.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.4
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• pp.127-134
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• 2019

Recently, the city development policies are being switched to the policies focusing on recession worldwide. Even though South Korea is also facing the phenomena that small and medium-sized cities are downsized because of a decrease in population and an aging society problem, there is lack of solutions and even they are still planning city development policies based on prospect of high growth. This study is featuring 4 viewpoints depending on shrinking population trend in 7 small and medium sized local cities, which are chosen as downsized cities. It is dealing with population peak, current population, 2030 population, and 2040 population viewpoints. And this study uses downsizing simulation that suggests optimum area that fits population and then shows visual check of the status of the small and medium sized local cities. The area of the small and medium sized local cities are expanded more than needs when they are on population peak point. However, they need only 20% to 25% of current area in 2030 and 2040. The most important thing is realizing the seriousness and facing up to the 'shrinking' phenomena that each small and medium-sized cities suffer. Therefore, this study has significance for presenting the status of small and medium-sized cities' problems in South Korea.