• Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.151-155
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• 2000

Phaeodactylum tricornutum (Bacillariophyceae) is a marine diatom which has been supplied as a food of bivalves. In this study, growth responses of P. tricornutum to some nitrogen sources and sodium were investigated by measuring cell number and contents of chlorophyll a in culture. In medium with nitrogen and sodium, brisk cell division occurred and maximum growth rate was respectively found in the medium with 150 mg/l of nitrate and 10 mg/l of ammonium and urea. At 10-500 mg/l ammonium and urea and 200-500 mg/l nitrate, specific growth rate decreased slightly. However, no cell division observed in sodium-deficient medium, regardless of presence or absence of nitrogen. This suggests that sodium is required for the nitrogen uptake of P. tricornutum, resulting nitrogen uptake leading to cell division. Also the upper limits of ammonium and nitrate for the growth of P. tricornutum seem to be 10 mg/l and 500 mg/l, respectively.

• Journal of Microbiology and Biotechnology
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• v.6 no.5
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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.

• Journal of Environmental Science International
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• v.6 no.5
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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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• v.14 no.6
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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.

• Asian Journal of Turfgrass Science
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• v.12 no.4
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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.

• Korean Journal of Organic Agriculture
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• v.11 no.1
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• pp.55-66
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• 2003

This study was carried out to investigate the effects of different plant growth media on the growth of tomato(Lycopersicum esculentum Mill.) seedlings during growth stages. The media were commercial plant growth medium 100％, earthworm cast (that was produced by vermicomposting of food waste and cattle manure) 100％, earthworm cast 50％ ＋ vermiculite 50％, earthworm cast 50％ ＋ perlite 50％, earthworm cast 40％ ＋ vermiculite 30％ + perlite 30％. Plant length(mm), number of leaves, leaf area($\textrm{cm}^2$), stem diameter(mm), plant dry mater were greatest till the 2nd week growth stages in the commercial plant growth medium plots, but those were higher in the earthworm cast than those in the other plant growth media at the later stages of this study(P<0.05). And relative growth rate of biological yield, relative growth rate of shoot and relative growth rate of root were highest in the earthworm cast till the 4th week growth stage. Therefore it can be implied that there is the possibility of potential utilization of earthworm cast, which was produced by vermicomposting of food waste and cattle manure, as vegetable growth medium.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.101-108
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• 1982

The effects of ginseng extract and ginseng saponin on the growth of bacterial cells were variable depending upon the species of bacterium and concentrations of saponin. Serratia marcescens and Aerobocter aerosenes showed the maximum growth in the basal medium pius 0.1% of ginseng extract, but did the suppressed growth in the medium plus above 1 % of ainseng extract. Stophylococcus aureus and Escherichia coli showed the maximum growth in the basal medium plus 5% of ginseng extract. The slightly accelerated growth was shown with Micrococus flavus and Aerobacter aerogenes cultivated in the basal medium plus 0.002% of ginseng saponin, but the remarkably supressed growth was done in the medium plus above 0.02% of ginseng saponin. Ginseng saponin functioned a physiologically suppressing factor of growth to genus Serratia, but no antimicrobial activity was found against Erwinia aroideae and Sarcina marginata. The substance causing the antimicrobial activity from ginseng saponin was proven to be a ginsenoside Rg$_1$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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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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• v.28 no.1
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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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• v.16 no.12
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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.