• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.2
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• pp.103-108
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• 2005

For more accurately describing the durations of the light and the dark phases of micro-algal cells over the whole light-dark cycle, and probing into the relationship between the liquid circulation time or velocity, the aeration rate and cell density, a series of experiments was carried out in 10 cm light-path flat plate photobioreactors. The results indicated that the liquid flow in the flat plate photobioreactor could be described by liquid dynamic equations, and a high biomass output, higher content and productivity of arachidonic acid, $70.10\;gm^{-2}d^{-1},\;9.62\%$ and 510.3 mg/L, respectively, were obtained under the optimal culture conditions.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.422-427
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• 2003

Rhodopseudomonas palustris P4 can produce $H_2$ either from CO by water-gas shift reaction or from various sugars by anaerobic fermentation. Fermentative $H_2$ production by P4 is fast, but its yield is relatively low due to the formation of various organic acids. In order to increase $H_2$ production yield from glucose, P4 was investigated for the photo-fermentation of acetate which is a major by-product of fermentative $H_2$ production. Experiments were performed in batch modes using both light-grown and dark-grown cells. When the dark-grown P4 was challenged with light and acetate, $H_2$ was produced with the consumption of acetate after a lag period of 25 h. $H_2$ production was inhibited when a nitrogen source, especially ammonium, is present. When the dark-fermentation broth containing acetate was adopted for photo-fermentation with light-grown cells, $H_2$ production and concomitant acetate consumption occurred without a lag period. The $H_2$ yield was estimated as 2.4 - 2.8 mol $H_2/mol$ acetate and the specific $H_2$ production rate was as 9.8 ml $H_2/g$ cell${\cdot}$h, The fact that a single strain can perform both dark- and light-fermentation gives a great advantage in process development Compared to a one-step dark-fermentation, the combined dark- and light-fermentation can increase the $H_2$ production yield on glucose by two-fold.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.548-561
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• 2020

Paecilomyces japonica is widely cultured to produce mycelium for medicinal and health food use. Illumination is an important factor in the growth and production of mycelium in submerged culture. The effects of different light-emitting diode (LED) combinations on the growth and cordycepin content as bioactive substances of mycelium were investigated. The results showed that the mycelium dry weights were lower under dark condition and red LED treatments. Dark condition, fluorescent light, and ultraviolet-A failed to increase the cordycepin content. Blue light was necessary to increase the cordycepin content, and a red-to-blue ratio of 3:7 induced the highest cordycepin content. The cordycepin contents of mycelium in submerged culture were significantly higher in a 12 h/day illumination time under red and blue (red-to-blue ratio of 3:7) LED treatments, showing an increase of up to 38% compared with those under the fluorescent-light control condition. The results demonstrated the roles of light with different wavelengths on the biosynthesis of cordycepin as bioactive substances. The low-heat release and replacement of traditional fluorescent lights with low-energy-consuming LEDs could increase the contents of bioactive substances. After optimization of the cordycepin production using response surface methodology (Box-Behnken design) to its canonical form, the optimum combination was found to be as follows: illumination time = 17.7 h/day, sugar content in the medium = 9.7 g/50 mL, and incubation time = 61.2 h. The model predicted a maximum response of 3779.2 ㎍/mL cordycepin yield.

• The Research Journal of the Costume Culture
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• v.13 no.5 s.58
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• pp.804-818
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• 2005

The purpose of this study is to investigate the effect of tone-on-tone coloration on the visual images of traditional Korean dress. The materials in the experiment developed for this study were made up of various stimuli and the response scales for each stimulus. The stimuli were 48 color pictures with various combination of colors, in which the tones of jackets and skirts were manipulated by computer drawing. 24 bi-polar adjectives, each of which was graded into seven in its degree, were used to evaluate each image. The subjects were 576 female students in Jinju City. This experiment was based on the $3{\times}4{\times}4$ factorial designs: color (red, yellow and green), jacket tone (vivid, light, dull and dark) and skirt tone (vivid, light, dull and dark). The results of the study can be summarized as follows; Impression factor of the stimuli consisted of the 5 different dimensions - youthfullness and activity, attractiveness, gracefullness, visibility, and tenderness. The colors and the tone of jackets and skirts used in this experiment influenced 5 impression dimension by interaction of two valuables or working independently. Yellow and green with vivid or light tone had an effect on the formation of youth and activity image, and dark-light combination had an effect on the formation of attractiveness image. In case of green color, light tone of a jacket and vivid or dull tone of a skirt affected gracefulness, while yellow has no impact on visibility image regardless of skirt tone. Red and yellow with vivid or light tone were a factor to decide tenderness.

• Korean Journal of Plant Resources
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• v.1 no.1
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• pp.88-92
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• 1988

The study was conducted to determine the optimal basal media and the concentration of plant growth regulator for germination of seeds and growth of plantlet from Dendrobium monile. The results obtained were summarized as follows. Germination was similar in light and dark condition, but the growth of plantlet after germination was better under dark than under light condition in several media. Germination was best in Hyponex and Kyoto solution medium among the 9 media tested. The number of roots/shoot was most in the Hyponex medium containing 0,1ppm NAA and 1.Oppm BA.

• Journal of the Korean Society of Food Culture
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• v.21 no.4
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• pp.414-419
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• 2006

The purpose of this study was to measure the factor influencing tourist preferences for leaf mustard iimchi. Among 250 questionnaires, 230 questionnaires were utilized for the analysis. Frequencies, conjoint model, max. utility model, BTL model, Logit model, K-means cluster analysis, and one-way ANOVA analysis were used for this study. The findings from this study were as follows. First, the Pearson's R and Kendall's tau statistics showed that the model fitted the data well. Second, it was found that total respondents and three clusters regarded taste and price as the very important factor. Third, it was found that the first cluster most preferred product with light red color, plain package, and mild taste sold at a cheap price in factory. The second cluster most preferred product with light red color, plain package, and moderately pungent taste sold at a expensive price in factory. The third cluster most preferred product with dark red color, shaped package, and highly pungent taste sold at a cheap price in factory. Fourth, it was found that the first cluster most preferred simulation product with light red color, shaped package, and mild taste sold at a cheap price in factory. The second cluster most preferred simulation product with light red color, shaped package, and moderately pungent taste sold at a cheap price in factory. The third clutter most preferred simulation product with dark red color, shaped package, and highly pungent taste sold at a cheap price in factory.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.292-296
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• 2002

Soybean seeds were treated with blue, red and far-red lights for 0, 6, 12, and 24 hours during 24-hour imbibition before culture for 6 days. The soybean sprouts raised were classified by their hypocotyl lengths; normal (＞4cm), abnormal (＜4cm) and non-germination, and their lateral roots, hypocotyl diameters and component dry weights were measured. Red light treatment and dark imbibition reduced the abnormal soybean sprouts more than far-red and blue light treatments, meaning that the former treatments produced more commercial sprouts. The lateral roots were more formed in blue light and dark imbibition than the other light treatments, but were completely blocked by any light treatment lasted during the whole imbibition. Although any light quality treatment did not influence their primary root lengths, blue light one lengthened the hypocotyl more than the others treated during the imbibition, and far-red light enlarged its diameter. Despite this morphological change, component, total or economic yield was not significantly different among the light quality treatments during the imbibition.

• Journal of Mushroom
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• v.20 no.4
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• pp.187-192
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• 2022

Wolfiporia cocos is an edible fungus commercially cultivated in Asia. To investigate metabolic changes of W. cocos mycelia under both light and dark culture conditions, gas chromatography mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) analyses were performed. In terms of the total amount of sugars, alcohols, amino acids, organic acids, fatty acids, and purines, there no significant differences between the W. cocos mycelia cultivated under light (L) or dark (D) conditions (p < 0.05). However, there were some differences with respect to the production of particular sugars and proteins. The levels of trehalose (L: 17.2 ± 0.3% vs. D: 13.9 ± 1.6%), maltose (L: 0.9 ± 0.1% vs. D: 0.3 ± 0.1%), turanose (L: 0.7 ± 0.2% vs. D: 0.1 ± 0.1%), glutamine (L: 1.6 ± 0.3% vs. D: 0.7 ± 0.2%), and proline (L: 0.3 ± 0% vs. D: 0.1 ± 0%) were all significantly higher under light condition (p < 0.05). In contrast, the levels of galactose (L: 13.7 ± 1.2% vs. D: 17.6 ± 2.0%), aspartic acid (L: 0.6 ± 0.1 % vs. D: 0.9 ± 0.1%), cystathionine (L: 0.6 ± 0.1% vs. D: 0.8 ± 0 %), and malic acid (L: 0.7 ± 0.1% vs. D: 1.2 ± 0.1%) were higher under the dark condition. It is worth noting that the amount of pachymic acid, a pharmaceutically active compound of W. cocos, was 1.68 times greater under the light condition (p < 0.05).

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.1
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• pp.32-36
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• 2003

Production of camptothecin ((PT) from callus cultures of Camptotheca acuminata Decne was affected by light and culture conditions. Among the culture media tested, modified B5 medium containing 3% (w/v) sucrose, 2 mg/L B,4-D, 2 times of MS medium vitamins, 500 mg/L casein hydrolysate, 250 mg/L myo-inositol, 0.05% (w/v) activated charcoal, and 0.15% (w/v) gelite was used for callus induction . The highest cell growth and CPT production were obtained in dark and green light condition, respectively. Photoperiod has no effect on cell growth and CPT production. Both cell growth and CPT production were also influenced by combination ratio of red and blue light .Cell growth and CPT production were the highest in the ratio of red and blue light,90:10.

• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.360-366
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• 2006

To investigate the effect of culture conditions on growth and ginsenosides accumulation, we cultured the ginseng hairy root under three different media, white light or ultra-violet irradiation. The MS/B5 medium containning MS basal salt and B5 vitamin was good for the growth and ginsenoside accumulation. The light during the culture period of ginseng hairy root was irradiated. The growth was abundant in the ginseng hairy root cultured in dark. But the ginsenosides accumulation was higher than in the ginseng hairy root cultured in the light irradiation. When the ginseng hairy root was cultured in 20 L bioreactor, the ginsenosides accumulation was observed at 34% higher than the hairy root cultured in dark. UV irradiated the ginseng hairy root during the culture period. The long time irradiation of UV was caused decreasing the growth of ginseng hairy root, but the accumulation of ginsenosidess was increased as to the irradiated time.