• Journal of Microbiology and Biotechnology
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• 제6권5호
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• pp.347-351
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• 1996

Flavonoid production by suspended cells of Scutellaria baicalensis Georgi was studied and the medium was optimized for cell growth and baicalin production. In SH medium the flavonoid production was not closely associated with the cell growth. A modified SH medium, FPM, was therefore designed for enhanced baicalin production. In FPM, both cell growth and baicalin production were increased by 1.5 times and 1.67 times than in the original SH medium, respectively. The increases could be attributed to the increased metabolic activities involved in the flavonoid biosynthesis as represented by enhanced activities of phenylalanine ammonia-lyase.

• 한국환경과학회지
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• 제6권5호
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• pp.481-488
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• 1997

Microorganisms capable of degrading trlchloroethylene(TCEI using phenol as a induction substrate were isolated from industrial effluents and soil. The strain MS-64K which had the highest blodegradablllty was identified as the genus Micrococcus. The optimal conditions of medium for the growth and blodegadatlon of trlchloroethylene were observed as follows; the initial pH 7.0, trlchloroethylene 1, 000ppm as the carbon source, 0.2% ${(NH_4)}_2SO_4$, as the nitrogen source. respectively. Lag period and degradation time on optimal medium were shorter than those on Isolation medium. Growth on the optimal medium was Increased. Addition of 0.1% Triton X-100 Increased the growth rate of Micrococcus sp. MS-64K, but degradation was equal to optimal medium. Trlchloroethylene degradation by Micrococcus sp. MS-64K was shown to fit logarithmic model when the compound was added at initial concentration of 1, 000ppm.

• Asian-Australasian Journal of Animal Sciences
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• 제14권6호
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• pp.811-815
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• 2001

The study evaluated different synthetic and semisynthetic media for maximal recovery of rumen bacteria and expression of their antibacterial activity. Rumen Glucose Cellobiose Agar (RGCA) medium was found to be the best for recovery of rumen bacteria. However, L-10 medium was the best for expression of antibacterial activity of ruminal isolates followed by Easy, M-10, RGCA and M-98-5 medium. The present study recommends the use of L-10 medium as the medium of choice for screening of antibacterial activity of ruminal isolates. Comparative evaluation of bacterial counts on different dietary regimes indicated significant difference between different growth media on a specific diet and between diets on specific growth media within a species. However, there is no overall significant difference between total bacterial counts obtained from rumen liquor of cattle and buffalo with respect to either the feeding regime or growth media. Feeding straw based diet to the animal is the best for high recovery of rumen bacteria.

• 아시안잔디학회지
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• 제12권4호
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• pp.195-202
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• 1998

The development of a protocol for high efficiency of embryogenic callus separation, maintenance and plant regeneration from the seeds of zoysiagrass cv. Zenith was studied. Embryogenic callus ratio is absolutely determined by genotype, but by adding high concentration of copper into medium, changing light condition and maintaining callus on initial induction medium for 8∼10 weeks, embryogenic callus can be easily distinguished and its growth can be promoted. There were significant differences among selected callus lines (each from one seed) according to their growth rates and regeneration percentages. Callus pre-treatment with activated charcoal inhibited callus growth, increased the level of precocious germination during culture and promoted shoot cluster formation after transfer to regeneration medium. For long-term callus maintenance, N6AA medium was better than MS medium, because the former inhibited non-embryogenic callus formation and kept vigor of embryogenic callus. The best callus lines Z-(5) has been successfully used for transformation and somaclonal variation selection in our laboratory.

• 한국유기농업학회지
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• 제11권1호
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• pp.55-66
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• 2003

본 연구에서는 음식물쓰레기와 축분의 vermicomposting 처리로 얻어지는 지렁이 분립을 이용하여 채소의 육묘상토 자재로서의 이용가능성을 조사하기 위해, 시판상토 100％, 지렁이분립 100％, 지렁이분립 50％ ＋ vermiculite 50％, 지렁이분립 50％ + Perlite 50％ 및 지렁이분립 40％ ＋ vermiculite 30％ ＋ perlite 30％의 각각 다른 지렁이분립 혼합비율이 토마토(Lycopersicum esculentum Mill.) 유묘의 생육에 미치는 영향을 조사하였다. 토마토 생육 2주째까지는 시판상토구가 전 처리구에서 초장, 엽수, 경경, 엽중, 경중, 지상부중, 근중 및 생물수량이 가장 높았지만, 이후부터는 지렁이 분립 100％구가 다른 처리구보다 유의하게 높았으며 (p<0.05), 시판상토구에 비해서도 양호한 생육을 나타내었다. 지렁이 분립과 Vermiculite를 혼합한 구는 시판상토구와 유사한 생육을 나타내었다. 한편 생물수량의 상대생장율(BYRGR), 지상부 무게의 상대생장율(RGR) 및 지하부무게의 상대생장율(RWGR)은 생육 4주 째까지 지렁이 분립 100％ 구가 다른 처리구 보다 유의하게 높았다(P<0.05).

• 한국미생물·생명공학회지
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• 제10권2호
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• pp.101-108
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• 1982

인삼extract와 인삼saponin의 세균 세포 증식에 대한 영향은 세균의 종 및 인삼 성분농도에 따라 차이가 있었다. Serratia marcescens, Aevobacter aerogenes등은 인삼extract 0.1%첨가 농도에서 최대 증식을 나타내었으나 1%, 농도 이상에서는 증식이 억제되었으며 Staphylo. coccus aureus, Escherichia coli등은 1% 농도에서 최대 증식을 나타내었으나 5% 농도에서는 증식이 억제되었다. 인삼 saponin 0.002 %, 농도에서는 Micrococcus flavus, Aerobacter aerogenes등은 증식이 약간 촉진되나 0.02%, 이상의 농도에서는 증식이 현저히 억제되고 Serratia속 세균에서는 인삼saponin이 증식 억제 인자로 작용하였으나 Erwinia aroideae, Sarcina margtnata등에서는 세균 증식에 무관한 것으로 나타났다. 이러한 인삼 saponin이 나타내는 항균활성의 원인 물질은 ginsenoside Rg$_1$이었다.

• 한국식품영양과학회지
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• 제33권5호
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• pp.797-802
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• 2004

L-Ascorbic acid (AsA), commonly known as vitamin C, which is one of the antioxidant vitamins, plays a role in cellular oxidant quenching. Some of the biochemical reactions in which it takes part have been traced through organ culture technique. But in cell cultured system, views on stimulatory and inhibitory action of AsA on cell growth are conflicting. Therefore, this study aimed to clarify the inhibitory action of high concentration AsA on the cell growth in Primary chondrocyte isolated from rat ribs. Cells were exposed to ascorbate at various concentrations. Supplement of AsA induced stimulation of cell growth in primary cultured cells of chondrocytes. Most remarkable stimulation of cell growth by AsA was found in primary cultured chondrocytes. However, it showed that they were dead in the medium which contained AsA at the concentration higher than 1.0 mM. This lethal effect of AsA causing the cell death was inhibited by the addition of catalase in the medium. This supposed that hydroxyl radical (ㆍOH) induced from $H_2O$$_2$ was actively cytotoxic agent. Based on the results, when AsA was added in medium at normal concentrations, the cell growth was stimulated by inducing the formation of extracellular matrix. On the contrary, if added in medium at excess concentrations, the cell growth was inhibited because $H_2O$$_2$ were generated from AsA in medium. Therefore, addition of AsA at the normal concentrations stimulates cell growth, but excess concentrations of AsA induces cell death.

• ALGAE
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• 제28권1호
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• pp.101-109
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• 2013

Some Chlorella species grow heterotrophically with organic substrate in dark condition. However, heterotrophic Chlorella species are limited and their optimum culture conditions are not fully known. In this study, three heterotrophic Chlorella species, two strains (C4-3 and C4-4) of C. vulgaris and one Chlorella sp. (C4-8) were examined on optimum culture conditions such as carbon source, temperature, and concentrations of nitrogen and phosphorus in Jaworski's medium (JM). And the growth and fatty acid composition of Chlorella were analyzed. For three heterotrophic Chlorella species, glucose (1-2%) as a carbon source only increased the growth and the range of optimum culture temperature was $26-28^{\circ}C$. Doubled concentrations of the nitrogen or phosphorus in JM medium also improved the growth of Chlorella. Chlorella cultured heterotrophically showed significantly higher growth rate and bigger cell size than those autotrophically did. C. vulgaris (C4-3) cultured heterotrophically showed the highest biomass in dry weight ($0.8g\;L^{-1}$) among three species. With respect to fatty acid composition, the contents of C16:0 and n-3 highly unsaturated fatty acid (HUFA) were significantly higher in autotrophic Chlorella than in heterotrophic one and those of total lipid were not different between different concentrations of nitrogen and phosphorus in JM medium. Among three Chlorella species in this study, C. vulgaris (C4-3) appeared to be the most ideal heterotrophic Chlorella species for industrial application since it had a high biomass and lipid content.

• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1856-1861
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• 2006

A Bacillus sp. A-6 strain that produced xylanase was isolated from rice bran. The optimal temperature and pH for xylanase activity of the culture supernatant of Bacillus sp. A-6 were 40$^{\circ}C$ and pH 7, respectively. The optimal temperature and pH for xylanase production in the xylan medium were 30$^{\circ}C$ and pH 9, respectively. The optimal concentrations of oat spelt xylan and peptone for xylanase production were 0.5% and 1.5%, respectively. The best nitrogen sources for xylanase production was beef extract, but xylanase production was also supported comparably by tryptone and peptone. The bacterial growth in the optimal xylan medium reached stationary growth phase after 12 h of incubation. The xylanase production in the culture supernatant increased dramatically during the initial 12 h exponential growth phase and then remained constant at 23.8-24.5 unit/ml during the stationary growth phase. The pH of the culture medium decreased from 8.8 to 6.7 during the exponential growth phase and subsequently increased to 8.1 during the stationary growth phase. Rice bran, sorghum bran, and wheat bran as well as oat spelt xylan induced xylanase production. The xylanase production was repressed when glucose was added to the xylan-containing medium.

• 국토계획
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• 제54권7호
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• pp.5-23
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• 2019

The central government has implemented policies to strengthen the competitiveness of small and medium sized cities for balanced development at the national scale. However, since it is often difficult to enhance the competitiveness through partial projects of each jurisdiction, many local governments collaborate at the regional scale. This suggests that a regional approach is important for the management of small and medium sized cities. On the one hand, the concept of network city suggests that various functional networks can affect the growth of small and medium sized cities. Given this background, the purposes of this study are to delineate regional boundaries at national scale and identify their relations of growth by using functional network and Moran's I index. The study uses the Markov-chain model and cluster analysis to delineate the regions, and Moran's I is employed to identify the relations of growth. The results show that interactions between jurisdictions through networks could be crucial factors for growth of small and medium sized cities, while the networks based on passenger travel and freight movement have different implications. The results suggest that policy makers should not only consider local level investments, but also take the characteristics of networks between cities into account for achieving balanced development and developing regeneration policies.