• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.130-136
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• 1998

An Immunostimulating polysaccharide was produced from the suspension culture of Angelica gigas H4, plant cells. In order to enhance the polysaccharide production by the A. gigas cell culture, medium composition and physical conditions were optimized. Schenk and Hildebrandt (SH) medium was selected as an optimal basal medium for the growth of A. gigas. The maximum cell and polysaccharide concentration obtained in SH medium were 15.8 g DCW/l and 0.85 g polysaccharide/l, respectively, at $25^{\circ}C$ under dark condition. For the enhanced polysaccharide production, a polysaccharide production medium (PPM) was established by modifying Gamborg B5 medium with optimized carbon sources, growth regulators, organic and inorganic elements. Optimal initial pH and temperature were 6.0-6.6 and $20^{\circ}C$, respectively, and the dark condition was better than the light condition. The maximum polysaccharide concentration of 1.5 g/l could be obtained through the optimization of the medium composition and physical conditions.

• Biomolecules & Therapeutics
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• v.9 no.3
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• pp.162-166
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• 2001

Helicobacter pylori is a major cause of gastric-associated diseases. In our previous study, the Adhesin/CTXA2B was expressed as insoluble recombinant chimeric protein derived from the H. pylori adhesin genetically coupled to CTXA2B subunit in Escherichia coli. Since it is very important to optimize IPTG concentration, culture temperature and composition of medium to maximize cell growth and productivity, these conditional growth factors were determined for increasing the productivity of the expressed Adhesin/CTXA2B chimeric protein in Escherichia coli JM101 carrying pTEDhpa/ctxa2b. Our data demonstrate that optimal medium for increased production of chimeric protein was a YCP/Glu medium composed of 2% yeast extract, 1% casamino acid, phosphate solution [0.3% $KH_2P0_4$, 0.4% $Na_2HP0_4$, 0.25% ($NH_4)_2HPO_4$], and 0.5% glucose. In addition, optimal concentration of IPTG was 1 mM and culture temperature, $37^{\circ}C$.

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.169-174
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• 2005

The optimal culture conditions were studied for plant regeneration from mesophyll protoplasts of Solanum sisymbriifolium. Axenic seedlings of S. sisymbriifolium were used as a explant for protoplast culture. Many viable protoplasts were isolated by incubating leaf slices in an enzyme solution containing 0.25% Meicerase and 0.05% Macerozyme for 16 hr at $25^{\circ}C$ without shaking. Protoplast density of $5.0{\times}10^4\;ml^{-1}$ in Kao medium containing 5.0 mg/L NAA, 1.0 mg/L 2,4-D and 1.0 mg/L BA was optimal for colony formation. Most colonies were formed when protoplasts were cultured at $25^{\circ}C$ after initial culture at $30^{\circ}C$ for one week. On the MS agar medium with 1.0 mg/L zeatin, 38.4% of protoplast-derived calli differentiated shoots. These shoots rooted on 1/2MS medium with 5.0 g/L sucrose and 2.5 g/L gellan gum, and developed into whole plants.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.52-60
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• 2001

This study was carried out to obtain the basic data on artificial culture of Hohenbuehelia petaloides. The optimum medium are glucose peptone medium (GP), Hennerberg medium, Phellinus igniarius medium (PIM), Lentinus edodes medium (LEM), Czapek dox medium. The optimum condition for the mycelial growth was $30^{\circ}C$ and pH 6.0. The carbon sources such as dextrine, fructose and lactose were favorable to mycelial growth. The optimal concentrations of carbon sources are 10% dextrin and fructose. As nitrogen sources, tryptone, casamino acid and histidine appeared to be favorable. The optimal concentrations of nitrogen sources are 1% soy tone and 0.3% ammonium nitrate. The optimal concentration of yeast extract is 0.4%. The mineral nutrients of $KH_2PO_4$, $K_2HPO_4\;and\;MgSO_4{\cdot}7H_2O$ were effective and the optimal concentrations were 0.046, 0.1 and 0.05%, respectively.

• Journal of Embryo Transfer
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• v.14 no.1
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• pp.39-46
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• 1999

To establish the optimal culture systems for production of transferable embryos in Korean Cattle, pregnancy rates of IVF-derived blastocysts according to different culture media, culture method and culture duration were compared. Development of IVF-derived embryos to blastocysts was most effective in YS medium group co-cultre with cumulus cells. Blastocysts cultured for 6 to 8 d in vitro showed higher hatching rate and good quality. Pregnancy rates after transfer of IVF-derived blastocysts cultured for 7 or 8 d were high. Through our experiments, it is considered that improvement of culture media and culture method is necessary for mass production of blastocysts with excellent of good quality in Korean Cattle.

• Korean Journal of Veterinary Research
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• v.26 no.2
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• pp.245-249
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• 1986

The present study has been carried out to investigate the optimal condition on the blastogenesis of guinea pig lymphocytes. A microculture system in conjunction with a semiautomatic multiple sample harvester(SAMSH) was used to study the in vito optimal condition of guinea pig lymphocytes. Data were presented to show many variables that are Involved in studying the responses of guinea pig lymphocyte in a microculture system to the stimulation of Concanavalin A(Con A) and lipopolysaccharide (LPS). Analysis indicated that the conditions for optimal Con A as measured by incorporation of $^3H$-TdR include : (1) use of RPMI-1640 as culture medium, (2) use of $6{\mu}g$ of Con A, per culture, (3) use of $1{\times}10^6$ cells per culture. Conditions for optimal stimulation with LPS mitogen were similar to those used for Con A.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.15-21
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• 1998

This study was carried out to determine the effects of plant growth regulators on cell culture and organogenesis from Sicyos angulatus L. using explants of leaves, stems and cotyledons. Optimal callus induction for S. angulatus was obtained on MS medium with 0.1mg/$\ell$ BA and 2.0mg/$\ell$ 2,4 -D from cotyledons, 0.1mg/$\ell$ BA and 5.0mg/$\ell$ NAA from leaves explants, Optimal media for subculture and growth of S. angulatus callus were 1/2 MS medium with 0.1mg/$\ell$ BA and 1.0mg/$\ell$ 2,4 -D for solid culture, and 0.1mg/$\ell$ 2,4-D for suspension culture. Many adventitious roots with some shoots were formed were formed from leaf and cotyledon explants of S. angulatus during callus induction with optimal combinations of plants growth regulators.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.285-290
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• 2008

This study was carried out to obtain an optimal liquid culture condition for Sarcodon aspratus mycelia. Among various basal culture media the GYS (glucoe-yeast extract-soytone) medium was the best for mycelial growth. The appropriate temperature was $25^{\circ}C$. Starch, maltose or glucose was excellent carbon sources for the mycelial culture, compared to others tested. As nitrogen nutrients, soytone and $NH_4-N$ were the best organic and inorganic nitrogen sources, respectively. Moreover, the optimal concentration of soytone was 3 g per one-liter medium. In addition, we also found that alanine, $(NH_4)H_2PO_4$, and nicotinic acid were the best aminoacid, phosphorus salt, and vitamin, respectively. When all optimal conditions described above were applied to culture medium, we were able to produce 5.7 g dry weight of S. aspratus mycelia per one-liter liquid medium within 20 days.

• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.145-147
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• 2005

Autocrine or paracrine mediators released by the early embryo are implicated in the support of embryonic development. Their mechanisms and optimal embryo density in the medium, however, are uncertain. This study was conducted to establish the optimal embryo density and culture medium volume in mouse parthenogenetic embryo culture. In experiment 1, culture of parthenogenetirally activated oocytes at a concentration of $2{\~}4$ embryos/${\mu}L$ significantly improved development to the blastoryst stage ($72{\%}{\leq}$) compared with culture at the lower ($0.2{\~}1$e mbryos/${\mu}L,\;0\~37.5\%$) and the higher ($5{\~}6$ embryos/${\mu}L,\;30\~53\%$) concentration for 120 h when the oocytes were cultured in a 5 ${\mu}L$ drop under mineral oil In experiment 2, the embryos cultured at a concentration of $2{\~}4$ embryos/${\mu}L$ in a 10 ${\mu}L$ drop ($81.1{\%}$) showed significantly higher blastocyst rates than those in a 5 ${\mu}L$ drop ($68.5{\%}$). This study optimizes in vitro culture condition by modifying embryo density and the volume of culture medium It may give appropriate level of autocrine and/or paracrine factors to enhance viability and subsequent normal development of mouse parthenogenetic embryos in vitro.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.311-316
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• 1997

A high xylitol producing yeast was isolated from the sludge of xylose manufacturing factory and then identified as Candida tropicalis DS-72 according to physiological properties. The strain was able to produce xylitol in a high concentration up to 72g/l from 100g/l xylose in 32 hours. Medium optimization for xylitol production by C. tropicalis DS-72 was performed. Effect of various nitrogen sources on xylitol production was investigated. Of nitrogenous compounds, yeast extract was the most suitable organic nitrogen nutrient for the enhancement of xylitol production. However, inorganic nitrogen resulted in a low cell concentration and did not produce xylitol. Effect of inorganic salts such as KH$_{2}$PO$_{4}$, and MgSO$_{4}$, 7H$_{2}$O on xylitol production was also studied. Optimal medium was selected as xylose 100g/l, yeast extract 10g/l, KH$_{2}$PO$_{4}$, 5 g/l and MgSO$_{4}$, 7H$_{2}$O 0.2 g/l. Xylitol of 88 g/l was produced from 100 g/l xylose in 30 hours using the optimal medium in a flask. In a fermentor, a fed-batch culture with 300g/l xylose was carried out. A final xylitol concentration of 240 g/l in the culture could be obtained in 43 hours of culture time by maintaining the high level of dissolved oxygen during growth phase and limiting the dissolved oxygen in the same culture during production phase. This result corresponded to a xylitol yield of 80% and a xylitol productivity of 5.58 g/1-h.