• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.6
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• pp.331-334
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• 2002

Culture conductivity and on-line NADH fluorescence were used to measure cellular growth in plant cell suspension cultures of Podophyllum hexandrum. An inverse correlation between dry cell weight and medium conductivity was observed during shake flask cultivation. A linear relationship between dry cell weight and culture NADH fluorescence was obtained during the exponential phase of batch cultivation In a bioreactor under the pH stat (pH 6) conditions. It was observed that conductivity measurement were suitable for biomass characterisation under highly dynamic uncontrolled shake flask cultivation conditions. However, if the acid/alkali feeding is done for pH control the conductivity measurement could not be applied. On the other hand the NADH fluorescence measurement allowed online-in situ biomass monitoring of rather heterogenous plant cell suspension cultures in bioreactor even under the most desirable pH stat conditions.

• 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.

• Proceedings of the Botanical Society of Korea Conference
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• 1995.06a
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• pp.40-56
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• 1995

During the past two decades, China has seen her great progress in plant biotechnology. Since the Chinese market of herb medicine is huge, while the plant resources are shrinking, particular emphasis has been placed in plant tissue and cell cultures of medicinal plants, this includes fast propagation, protoplast isolation and regeneration, cell suspension cultures and large scale fermentation. To optimize culture conditions for producing secondary compounds in vitro, various media, additives and elicitors have been tested. Successful examples of large scale culture for the secondary metabolite biosynthesis are quite limited : Lithospermum ery throrhizon and Arnebia euchroma for shikonin derivatives, Panax ginseng, P. notoginseng, P. quinquefolium for saponins, and a few other medicinal plants. Recent development of genetic transformation systems of plant cells offered a new approach to in vitro production of secondary compounds. Hairy root induction and cultures, by using Ri-plasmid, have been reported from a number of medicinal plant species, such as Artemisia annua that produces little artemisinin in normal cultured cells, and from Glycyrrhiza uralensis. In the coming five years, Chinese scientists will continue their work on large scale cell cultures of a few of selected plant species, including Taxus spp. and A. annua, for the production of secondary metabolites with medicinal interests, one or two groups of scientists will be engaged in molecular cloning of the key enzymes in plant secondary metabolism.

• Korean Journal of Pharmacognosy
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• v.16 no.3
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• pp.171-174
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• 1985

Panax ginseng root has been widely used as an important drug for thousands years in China, Korea and Japan. The main effective components of ginseng have been believed to be saponins. However, ginseng cultivation is very difficult and needs many years for growth. It has already been shown that Panax ginseng callus produces a considerable amount of the same kinds of saponins as in intact plants. Various culture conditions were examined for increased production of ginseng saponins by cell culture. The saponin contents and the growth rates in two cell lines of ginseng callus were compared in static and suspension cultures, rotary and reciprocal shaking cultures. It was shown that the growth rate in rotary shaking cultures of D5-B2K-B2K callus was the highest and ginseng saponin production was most effective in reciprocal cultures of D5-B2K-B2K callus. The saponin content per fresh weight of the culture was 1.03 times higher than that of the fresh ginseng root.

• Journal of Microbiology and Biotechnology
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• v.23 no.11
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• pp.1586-1597
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• 2013

Energy-efficient metabolic responses were often noted in high-productive cultures. To better understand these metabolic responses, an investigation into the relationship between metabolic responses and energy regulation was conducted via a comparative analysis among cultures with different energy source supplies. Both glycolysis and glutaminolysis were studied through the kinetic analyses of major extracellular metabolites concerning the fast and slow cell growth stages, respectively, as well as the time-course profiles of intracellular metabolites. In three cultures showing distinct antibody productivities, the amino acid metabolism and energy state were further examined. Both the transition of lactate from production to consumption and steady intracellular pools of pyruvate and lactate were observed to be correlated with efficient energy regulation. In addition, an efficient utilization of amino acids as the replenishment for the TCA cycle was also found in the cultures with upregulated energy metabolism. It was further revealed that the inefficient energy regulation would cause low cell productivity based on the comparative analysis of cell growth and productivity in cultures having distinct energy regulation.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.289-291
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• 1999

Hypocotyl explants from 7 days old seedlings of one $F_1$ hybrid cultivar and two pure lines of cucumber formed embryogenic calli at frequencies of up to 8% when cultured on Murashige and Skoog medium (MS) supplemented with 1 mg/L 2,4-D for 3 weeks. Embryogenic calli gave rise to somatic embryos. When slices of somatic embryos were cultured on the same medium for 4 weeks, they formed embryogenic calli. Embryogenic cell suspension cultures were established with embryogenic calli in MS liquid medium with 1 mg/L 2,4-D. Embryogenic potential of cell suspension cultures was maintained by subculturing every seven days. When the level of 2,4-D in the medium was lowered to 0.2 mg/L by diluting with liquid MS basal medium, embryogenic cell suspension cultures underwent development into numerous somatic embryos. When plated onto MS basal medium, over 95% of somatic embryos developed into plantlets. Plantlets were transplanted to potting soil and grown to maturity.

• International Journal of Oncology
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• v.56 no.6
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• pp.1490-1498
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• 2020

Multicellular tumor spheroids (MTSs) of malignant cells can display cell-cell and cell-matrix interactions, different from monolayer cultures. The objective of the present study was to examine difference in intercellular and cell-matrix interaction between monolayered cultures and spheroid cultures. Expression levels of cell adhesion molecules (CAMs) and epithelial-mesenchymal transition (EMT) signaling molecules in monolayered cells and MTS cells were compared. The motility of single cells dispersed from each culture was evaluated using a live-cell imaging device. The effect of an E-cadherin neutralizing antibody, DECMA, was also compared between the two cultures. Among various CAMs, only E-cadherin was increased in MTSs. The motility of single cells dispersed from MTSs was higher than that from monolayered cells. Compared with monolayered cells, the molecular weight (MW) of β1 integrin was decreased during MTS formation, particularly during the early stage. This notable reduction was maintained when DECMA was used to treat MTSs. Additionally, the expression levels of the EMT signaling molecules Snail and ILK increased more in MTSs than in monolayered cells. The blocking of E-cadherin elicited increased expression levels of EMT molecules and cellular motility only in MTSs. In conclusion, the alteration of E-cadherin expression and presence of low-MW β1 integrin in MTS may enhance cell motility via the upregulation of EMT signaling molecules that may be intensified by blocking E-cadherin.

• KSBB Journal
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• v.15 no.4
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• pp.337-341
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• 2000

The decanter is very useful to harvest biomass from plant cell cultures in large-scale process. It is very important to obtain high yield and low moisture content in recovered biomass so as to minimize solvent usage in subsequent extraction steps. Effluent clarity was also affected by the differential speed although this affect was more dramatic at higher flow rates than at lower flow rates. Moisure content was largely unaffected by flow rate. A decrease in moisture content was evident as differential speed decreased.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.382-385
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• 2000

A mathematical model was developed, based on the time dependent changes of the specific growth rate, for prediction of the typical microbial cell growth in batch cultures. This model could predict both the lag growth phase and the stationary growth phase of batch cultures, and it was tested with the batch growth of Trichoderma reesei and Lactobacillus delbrueckii.

• Korean Journal of Veterinary Service
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• v.25 no.3
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• pp.295-297
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• 2002

This experiment was done to set up the immunohistochemical detection method for infectious hematopoietic necrosis virus(IHNV) antigens in the monolayers of CHSE-214 cell cultures inoculated with IHNV. Specific identification of IHNV antigens was detected in the cytoplasms of infected cells by the use of monoclonal antibodies to glycoproteins. The specific positive signal was observed as a distinct red color. The result showed that streptavidin alkaline phosphatase immunohistochemistry specifically identified IHNV antigens in infected cultured cells.