• Clinical and Experimental Reproductive Medicine
• /
• v.24 no.2
• /
• pp.233-239
• /
• 1997

Embryos of most mammalian species grown in vitro would undergo developmental arrest at the approximate time of genomic activation. Stage-specific cell block and the resulting rapid loss of embryo viability in conventional culture media have limited the duration for which embryos may be cultured prior to transfer. As a result, embryos are usually transferred to the uterus at the 4-to 8-cell stage to avoid the loss of viability associated with long-term in vitro culture. Early transfer has led to asynchrony of the endometrium-trophectoderm interaction at the time of implantation and a resultant reduction in the rate of implantation. To overcome these problems, a variety of co-culture systems has been devised in which embryos can develop for a longer period prior to embryo transfer. Vero cells, derived from African green monkey kidney, share a common embryologic origin with cells from the genital tract. In addition, they are potentially safe to use, since they are highly controlled for viruses and other contaminants. Therefore, co-culture using Vero cells has been widely utilized to enhance embryo viability and development, although not without controversies. We thus designed a series of experiments to demonstrate whether Vero cells do indeed enhance mouse embryo development as well as to compare the efficacy of co-culturing mouse 1-cell embryos on Vero cell monolayer in both Ham's F-10 and human tubal fluid (HTF) culture media. 1-cell stage ICR mouse embryos were cultured either in the presence of Vero cells (Group A) or in conventional culture medium alone (Group B). In Ham's F-10 significantly more 3-to-8cell embryos developed in group A than group B (59.8 versus 10.0%; p<0.01). In contrast, there was no significant difference in embryonic development both group A and group B in HTF. However, significant differences were noted only in later embryonic stage (13 and 0%; p<0.05 of group A and B respectively, hatching or hatched). In Ham's F-10, we also could observe the beneficial effect of Vero cell on hatching process (70.7 and 42.1%; p<0.05 of group A and group B respectively).

• Journal of Bio-Environment Control
• /
• v.9 no.1
• /
• pp.66-72
• /
• 2000

Effects of irrigation control by time and integrated solar radiation on musknelon quality in perlite culture were investigated. Sugar content of melon flesh was high in the irrigation treatment at the following times 6：00, 8：00, 10：00, 11：00, 12：00, 12：30, 13：00, 13：30, 14：00, 14：30, 15：00, 16：00, and 17：00(T-2), compared to the irrigation treatment at every hour from 6：00 to 18：00(T-1) within the irrigation experiment controlled by time. Within the irrigation experiment controlled by integrated solar radiation, sugar content was as high as 15.7(Brix$^{\circ}$) in the 240Wh.m$^{-2}$ , compared to the 180, the 200, and the 220Wh.m$^{-2}$ . Fruit firmness was low in T-2 within the Irrigation experiment by time and in the 220Wh.m$^{-2}$ within the irrigation experiment by integrated solar radiation. Fruit size was smaller in the treatment controlled by integrated solar radiation than by the time treatment. Fruit weight was the heaviest in T-1. The weight of the shoot except for the fruit was lower in treatment of irrigation by integrated solar radiation than by time. In conclusion it is suggested that the appropriate integrated solar radiation pet each irrigation cycle should be 180~20Wh.m$^{-2}$ in the early growing stage, and then gradually increased to 240Wh.m$^{-2}$ from net formation to harvest time.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.321-324
• /
• 2000

The Effect of pH red pigment production by Monascus purpureus ATCC 16365 has been studied in pH-controlled batch fermenter culture. A maximum of yellow and red pigments were detected using UV-Vis spectrophotometer at 385nm and 495nm, respectively. Fungal growth and pigment production were favoured at low pH(pH 4.0-5.5). Especially extracellular formation rate of orange to yellow pigment was decreased compared with that of orange to red pigment at pH 7.0. In addition, the enhancement of ratio of extracellular to intracellular pigment and the red pigment production in pH 7.0-controlled batch fermenter was observed. However, the pH 7.0-controlled batch cultures depressed the total production of pigments. The pH change from 4.0 to 7.0 during batch fermenter cultivations sharply increased both red pigment production and the extracellular composition.

• Korean Journal of Medicinal Crop Science
• /
• v.24 no.3
• /
• pp.198-206
• /
• 2016

Background: Electrical conductivity (EC) and pH are important features of nutrient solution, affecting both growth and quality of crops by altering nutrient uptake. Methods and Results: The pH values of nutrient solutions were controlled at 5.0, 5.5, 6.0, 6.5 and EC values were controlled at 0.68, 0.84, 1.23, 1.41 dS/m. Gingesng root weights were higher during the initial growth period when the plants were treated with low pH and low EC nutrient solutions. However, the higher pH and EC levels, the greater the increase in the rate of root weight between the initial and middle growth periods. The highest ginsenoside amount changed during growth period. The total ginsenoside amount was highest in the root, and the lowest in leaves at 45 and 90 days after treatment, respectively, with solution at a pH of 6.0. After 135 days of treatment, the highest total ginsenoside amount was detected in root treated with soluton with EC values of 1.23 dS/m. Conclusions: For the cultivation of ginseng using a nutriculture system, the pH and EC values of nutrient solutions should to be controlled based on the stage of growth and targeted plant organ (root or leaves).

• Macromolecular Research
• /
• v.11 no.5
• /
• pp.334-340
• /
• 2003

In order to fabricate new sustained delivery device of nerve growth factor (NGF), we developed NGF-loaded biodegradable poly(L-lactide-co-glycolide) (PLGA, the mole ratio of lactide to glycolide 75:25, molecular weight: 83,000 and 43,000 g/mole, respectively) film by novel and simple sandwich solvent casting method for the possibility of the application of neural tissue engineering. PLGA was copolymerized by direct condensation reaction and the molecular weight was controlled by reaction time. Released behavior of NGF from NGF-loaded films was characterized by enzyme linked immunosorbent assay (ELISA) and degradation characteristics were observed by scanning electron microscopy (SEM) and gel permeation chromatography (GPC). The bioactivity of released NGF was identified using a rat pheochromocytoma (PC-12) cell based bioassay. The release of NGF from the NGF-loaded PLGA films was prolonged over 35 days with zero-order rate of 0.5-0.8 ng NGF/day without initial burst and could be controlled by the variations of molecular weight and NGF loading amount. After 7 days NGF released in phosphate buffered saline and PC-12 cell cultured on the NGF-loaded PLGA film for 3 days. The released NGF stimulated neurite sprouting in cultured PC-12 cells, that is to say, the remained NGF in the NGF/PLGA film at 37 $^{\circ}C$ for 7 days was still bioactive. This study suggested that NGF-loaded PLGA sandwich film is released the desired period in delivery system and useful neuronal growth culture as nerve contact guidance tube for the application of neural tissue engineering.

• Korean Journal of Agricultural Science
• /
• v.20 no.1
• /
• pp.34-42
• /
• 1993

Effects of salt concentrations on the cell growth and the pigment accumulation were investigated in cell suspension culture of Vitis vinifera and Phytolacca americana L.. The growth pattern of vine cell in control was showed the normal exponential growth pattern, but in the dilution media delay the exponential growth pattern from 4 to 8 days after culture. Maximal accumulation of anthocyanin was observed at 12 days after culture in all treatments. In cell suspension culture of Phytolacca, accumulation of betacyanin occurred in parallel with the cell growth pattern and maximal accumulation of betacyanin was observed after 8 days of culture. In the vine cell culture, the cell growth was showed the peak at 87.6mM of sucrose in the medium and reduced at over this concentration. Maximal anthocyanin accumulation was showed at 146mM of sucrose. In the higher concentrations of sucrose, the cell growth was rapidly decreased, but the accumulation of anthocyanin was not. Otherwise, in case of Phytolacca cell culture, betacyanin accumulation was showed in parallel with the cell growth increased with sucrose concentration. It was suggested that the anthocyanin of vine and the betacyanin of Phytolacca were controlled by different mechanisms.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.65 no.4
• /
• pp.365-376
• /
• 2020

Immature embryogenesis is a useful process in wheat tissue culture, including transgenic technology, because of its high regeneration efficiency compared to that in other tissues. However, it is a very labor-intensive and time-restrictive method, because the preparation of immature embryos is limited to the optimal time after flowering. In this experiment, 'Speed Breeding', a breeding technique that accelerates breeding generation advancement by extending the photoperiod, was applied to the wheat variety 'Bobwhite'. A controlled growth room was constructed by adjusting the photoperiod (22-hour light/2-hour dark) using LED lights at temperature of 22℃. After vernalization of the Bobwhite seeds at 4℃ for 4 weeks, the seedlings were grown in a controlled growth room and a greenhouse to compare the heading date. In both conditions, calli were induced from immature embryos on the 11^th day after flowering. After 4 weeks, the calli were transferred to a regeneration medium. Regeneration efficiencies under greenhouse conditions and Speed Breeding conditions were determined as 45.05% and 43.18%, respectively. Antioxidant enzyme activity and reference gene expression analysis were performed to confirm the presence of stress due to an extremely long-day photoperiod. As a result, the antioxidant enzyme activity was not distinguished from that of the greenhouse condition. The reference gene expression analysis revealed that the PsaA and CDC genes were highly expressed under the Speed Breeding condition. However, expression of PsbA was similar expression in both conditions. These results will provide useful information for the application of immature embryogenesis to the wheat transformation system.

• Microbiology and Biotechnology Letters
• /
• v.45 no.2
• /
• pp.149-154
• /
• 2017

To increase the efficiency of esterase production by Bacillus, high cell-density culture of recombinant Escherichia coli through fed batch fermentation was tested. Cells were cultured to $OD_{600}$ of 76 (35.8 g/l DCW) with dissolved oxygen level controlled to least above 30% air saturation by supplying pure oxygen. Cells were cultured to an $OD_{600}$ of 90 (42.4 g/l DCW) with glucose feeding controlled to at least 1 g/l. However, the cells reached stationary phase at the late stage of culture, despite glucose being supplied. Cells were cultured to an $OD_{600}$ of 185 (87.3 g/l DCW) by supplying additional medium with fortified yeast extract. To increase the productivity of the recombinant protein, cell growth and esterase productivity based on induction time were evaluated. Late exponential phase induction for esterase production in fed batch fermentation resulted in maximum optical density $OD_{600}$ of 190 (89 g/l DCW) and maximum esterase activity of 1745 U/l, corresponding to a 5.8-fold enhancement in esterase production, compared to the early exponential phase induction. In this study, we established fermentation methods for achieving maximum production of Bacillus-derived esterase by optimizing IPTG induction time in high-cell density culture by supplying pure oxygen and a nitrogen source.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.440-444
• /
• 2003

A new approach for ground water treatment combines a permeable Fe(0) barrier to breakdown higher chlorinated solvents like PCE and TCE with a down gradient aerobic biological treatment system to biotransform less chlorinated solvents, such as DCE and vinyl chloride (VC). The expected bacterial performance down gradient of an Fe(0) barrier was evaluated through laboratory batch experiments with a toluene-degrading mixed culture that cometabolically transforms cis-1,2-DCE and VC. The amount of cis-1,2-DCE (initially at 2,000 ppb) and VC (initially at 2,000 ppb) transformed was controlled by the initial toluene(20,000 ppb) concentration. VC was removed much more effectively than Cis-1,2-DCE, and a higher toluene concentration in comparison to the co-substrate concentrations was needed for complete co-substrate removal. Overall, the coupling of an Fe(0) barrier and subsequent biodegradation appears feasible for remediation of complex mixtures of chlorinated solvents and petroleum hydrocarbons in groundwater.

• The Research Journal of the Costume Culture
• /
• v.15 no.5
• /
• pp.863-874
• /
• 2007

The propose of the study was to evaluate impression effects and likeness of clothing styles and make-up types. The stimuli were composed of 4 clothing styles(base, natural, romantic, classic) and 4 make-up types(no make-up, natural, romantic, classic). The subjects were 512 male and female university students in Daejeon and Chungnam province. The study consisted of a survey and quasi- experiment. The experimental materials used for this study were 16 stimuli, 32 hi-polar adjectives, and likeness scale were composed of 7-point Likert type scales. As a result, the clothing styles and make-up types effected on the 4 impressional dimensions: grace, evaluation, salience, and dynamism. The clothing styles effected on grace, salience and dynamism dimension and the effect of dynamism dimension was the most powerful among the dimensions. The make-up types effected on all of the 4 impression dimensions and the effect of salience dimension was the most powerful among the dimensions. The interaction effects existed between the clothing styles and make-up types in salience dimension. The likeness showed significant difference only on the make-up types. The effect of grace dimension was the most powerful among the dimensions. The main reason that make-up effect appears greatly could be analyzed into that clothes color is controlled by white. The results suggest the necessity of succession study about the effect of clothes color.