• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.298-304
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• 1997

Thermus caldophilus GK24 was selected as sources of thermostable $\beta$-galactosidase from a survey of genus Thermus. T. caldophilus GK24 (Tca) $\beta$-galactosidase was found to be inducible. The enzyme was optimally active at 75$\circ$C. Enzyme induction was achieved by addition of lactose, galactose and cellobiose to basal media. The addition of glucose to culture media had a repressive effect on further enzyme synthesis. T caldophilus GK24 was tested for production of $\beta$-galactosidase by addition of various concentration of lactose, galactose and cellobiose to standard media. Cellobiose was found to be effective for the $\beta$-galactosidase induction. The optimal induction medium for production of $\beta$-galactosidase was composed of 0.2% cellobiose, 0.3% bactotryptone, 0.3% yeast extract, basal salts and Tris/HCI(pH 7.8). The activity of the enzyme in the optimal induction medium increased nearly 16.5-fold compared to the standard medium. Tca $\beta$-galactosidase was detected when cell extracts was subjected to electrophoresis in a nondenaturing polyacryamide gel and stained for activity with 6-bromo-2-naphtyl-$\beta$-D-galactopyranoside(BNG).

• Korean Chemical Engineering Research
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• v.44 no.1
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• pp.52-57
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• 2006

Bacterial cellulose (BC) was produced by Gluconacetobacter hansenii PJK (KCTC 10505 BP) strains using the waste of beer fermentation broth. It contained more C and N than a basal medium with a small amount of S and more than 4％ ethanol. The amount of BC produced in a shaking culture using the waste of beer fermentation broth was nearly the same as that of a basal medium. The production of BC decreased in a shear stress field in a jar fermenter although the conversion of cellulose producing ($Cel^+$) cells to non-cellulose producing ($Cel^-$) mutants was not severe. This study showed that the waste of beer fermentation broth is an inexpensive carbon, nitrogen source with ethanol and thus a worthy substitute for the conventional medium for BC production.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.171-175
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• 1999

We examined the effects of various basal media and exogenous auxins on the growth and saikosaponin production in hairy root cultures of Bupleurum falcatum. Of the various media tested, 2RCM medium was superior for growth and saikosaponin content, in which saikosaponin a, c, and d was produced, however MS medium was resulted in extremely low level in saikosaponin production. By the treatment of 0.5 mg/L IBA the growth rate was increased by about 60% in 2RCM medium, whereas both IAA and IBA showed a potent inhibition effect in saikosaponin biosynthesis by the treatment of 0.01 mg/L~5mg/L.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.82-82
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• 1995

Regulation of enzyme synthesis by transcriptional and translational control systems provides rather stable adaptation to change of amino acid level in the growth medium, while manipulation of enzyme activity through endproduct feedback inhibition represents rather short-term and reversible ways of adjusting metabolic fluctuation of amino acid level. Various control mechanisms interplay to regulate genes encoding enzymes for amino acid biosynthesis in the yeast, Sacchromyces cerevisiae. When amino acids are in short supply, genes under a cross-pathway regulatory mechanism Or general amino acid control (general control) increase their action, in which Gcn4p is the major positive regulator of gene expression. When cells are cultured in minimal medium, basal level expression is also regulated by supplementary control elements, where inorganic phosphate level is additionally involved. Most of amino acid biosynthetic genes are also regulated by the level of endproduct of the pathway. This pathway-specific regulatory mechanism is called specific amino acid control (specific controD, under which gene expression is reduced when endproduct is present in the medium. Derepression of a gene through general control can be usually overridden by repression through specific control, where the endproduct level of that particular pathway is high and not limiting. In this presentation, regulatory factors for basal level expression and general control of yeast amino acid biosynthesis will be discussed, m addition to pathway-specific repression patterns and interaction between CrOSS- and specific-control mechanisms. Preliminary results are also presented from the investigation of the cloned genes in the threonine biosynthetic pathway of the yeast. yeast.

• Korean Journal of Plant Resources
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• v.22 no.6
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• pp.584-591
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• 2009

Adventitious root culture was established in the Jawahar variety of Withania somnifera using MS basal medium supplemented with 0.5 (mg/l) IAA and 2.0 (mg/l) IBA. Root tips from germinated seedlings, MS0 maintained plants and adventitious roots were maintained in suspension medium (1/2 MS basal medium supplemented with 3% sucrose) for a period of 1 to 6 months. The weight gain in roots was noted and the withanolides were extracted from the dry roots using solvents petroleum ether, 50% ethanol and chloroform. The withanolides in the chloroform fractions of all root samples analyzed were compared using thin layer chromatographic analysis. Withanolide content in adventitious root sample was found to be superior compared to other roots at any given point of time during the 6month growth period.HPLC analysis of in vitro adventitious roots showed the presence of a new compound.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.137-141
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• 2002

Anabaena variabilis ATCC 29413 grew in chromium (Cr) containing Chu-10 (basal) and nitrate-supplemented media, and the growth of the organism in $100{\mu}M$ chromium was found to be 50% of that in control medium. The growth in nitrate $({NO_3}^-)$ supplemented cultures was better as compared to cultures grown in basal medium. Free cells from basal and nitrate-supplemented media removed 5.2 and 7.4 nmol of chromium $mg^{-1}$protein in 8 h, respectively, from the medium containing $30{\mu}M$ chromium. The efficiency of chromium removal increased 7-fold in imidazole buffer (0.2 M, pH 7.0). A cell density equivalent to $100{\mu}g$ protein $ml^{-1}$ was found to be optimum for maximum Cr removal. Entrapment of cells in calcium-alginate beads did not affect the rate of Cr uptake by the cells. The efficiency of the laboratory-scale continuous flow bioreactor $(12.5{\times}2cm)$ loaded with alginate-immobilized cells (10 mg protein) and fed with $30{\mu}M$ chromium solution was compared at different flow rates. The efficiency of the bioreactor varied with flow rates. In terms of percent removal of Cr from influent, a flow rate of 0.1 ml $min^{-1}$ was found to be optimum for 6 h (54% Cr removal efficiency). Maximum amount of Cr (883 nmol) was removed by the cells in 3 h at a flow rate of 0.5 ml $min^{-1}$. The potential use of A. variabilis in removing Cr from industrial effluents is discussed.

• Journal of Life Science
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• v.14 no.5
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• pp.855-858
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• 2004

The experiment was conducted to investigate optimal condition for callus induction and plant regeneration for transformation system of gerbera. Callus induction was more effective in 'white day' then other two cultivar 'Songsongee' and 'Love Song' The optimized plant growth regulators concentration on callus induction, was MS basal medium with NAA 0.1 mg/L＋ TDZ 0.5 mg/L. The optimized plant growth regulators concentration on plant regeneration, which was used MS basal medium was IAA 1.0 mg/L ＋ BA 1.0 mg/L ＋ Zeatin 0.1 mg/L. The optimized petiole age for more effective plant regeneration was 32 days petiole after in vitro subculture and MS basal medium strength was 1/2 MS strength.

• Korean journal of applied entomology
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• v.19 no.2 s.43
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• pp.91-95
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• 1980

The experiment was conducted to culture callus tissue induced from foliage leaf of garlic bulb for the production of virus-free stocks and for the reduction of expenses for seeds, The following results were reached. 1. Linsmaier-Skoog basal medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) $10^{-5}M$ and benzyladenine $10^{-5}M$ showed the most effective for the induction for the induction of garlic callus. 2. The growth rate of callus was the highest in Linsmaier-Skoog basal medium containing kinetin $10^{-6}M\;and\;2,4-D\;10^{-6}M$ 3. The results of periodical assay of virus concentration in callus tissues showed that virus was almost eliminated by repeated transfer of translucent and soft tissue for eight generations. 4. When virus-free garlic callus tissues were transfered to Murashige-Skoog basal medium containing kinetin $10^{-5}M$ and naphthaleneacetic acid $5\times10^{-6}M$, the tissues were redifferentiated and formed plantlet.

• Mycobiology
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• v.37 no.1
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• pp.28-30
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• 2009

This study was aimed at evaluating the growth promoting effect of symbiotic algal polyol (ribitol) and plant hormones on the lichen-forming fungi (LFF), Ramalina farinacea (CH050010 and 40403) and Ramalina fastigiata. The addition of ribitol to basal (malt-yeast extract) medium enhanced the relative growth rates of all three LFF. R. farinacea (CH050010), R. farinacea (40403) and R. fastigiata (H06127) showed 35.3%, 29.0% and 29.3% higher growth rates, respectively, compared to the control. IBA (indole-3-butyric acid) and TIBA (2,3,5-tridobenzoic acid) also increased growth rates of the LFF by 34 to 64% and 7 to 28%, respectively, compared to the control. The combination of ribitol with IBA or TIBA synergistically increased the growth of all LFF. For example, ribitol and IBA treatments increased growth rates of R. farinacea (CH050010), R. farinacea (40403) and R. fastigiata (H06127) by 79.4%, 40.3% and 72.8% in, respectively, compared to those grown on the basal medium. The stimulating effect of ribitol and IBA on the LFF growth induced vertical development of the fungal mass in culture. We suggest that lichen-forming fungal growth of Ramalina lichens can be stimulated aposymbiotically by supplementing polyols and plant hormones to the basal medium in the mass production of lichen secondary metabolites under large scale culture conditions.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.409-412
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• 2019

We investigated the development of a micropropagation protocol for multiplication of calla 'Gagsi' by using shoots as explant. The callus was induced on Murashige and Skoog (MS) basal medium containing cefotaxime antibiotics (25, 50, 100 mg/L). Also, MS basal medium with NAA 0.5 mg/L and BA 1.0 mg/L was used. The callus induction and browning rates were compared by treatment supplemented cefotaxime 25, 50 and 100 mg/L in basal MS medium. The callus induction rate was 10.5 % and browning rate was also, 10.5 % on the MS containing 25 mg/L. In the MNB containing cefotaxime, the callus induction rate was 34.5 % and browning rate was 27.0 %. The cefotaxime experiment has been widely used in previous studies. It is thought that it will help establish the mass multiplication system by positively affecting the growth and browning reduction of calla plants.