• KSBB Journal
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• v.13 no.3
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• pp.259-267
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• 1998

Optimal feeding strategies in bioreactor operation of Scutellaria baicalensis G. plant cell culture were investigated to maximize the production of flavone glycosides by using a structured kinetic model which can predict culture growth and flavone glycosides synthesis in a rigorous, quantitative manner. For the production of baicalin and wogonin-7-0-GA, the strategies for glucose feeding into Scutellaria baicalensis G. plant cell culture were proposed based on the model, which are a periodic fed-batch operation with maintenance of cell viability and of specific production rate respectively, and a perfusion operation with maintenance of specific production rate for baicalin and wogonin-7-0-GA. Simulation results showed that the highest volumetric concentration of flavone glycosides was obtained in a periodic fed-batch operation with maintenance of cell viability among all the suggested strategies. In the periodic fed-batch operations, the higher volumetric production of flavone glycosides was achieved compared with that in the perfusion operation. It can be concluded that a periodic fed-batch operation with maintenance of cell viability would be the optimal and practical operating strategy of Scutellaris baicalensis G. plant cell culture for the production of flavone glycosides.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.447-453
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• 2015

We determined the optimal culture conditions for obtaining the maximum number of intestinal bacteria from the olive flounder Paralichthys olivaceus, and studied bacterial diversity using both culture-dependent and culture-independent methods. Using six culture conditions, mean bacterial numbers were greater than $10^6$ per gram of gut mucus, regardless of the medium. However, the bacterial diversity, based on colony morphology, appeared much higher on Marine agar (MA) and Zobell 2216 agar than on other media. We found eight and 17 cultured bacterial phylotypes with 99% minimum similarity in gut mucus grown on MA and tryptic soy agar, respectively. Furthermore, we used genomic DNA extracted from gut mucus to generate 78 random clones, which were grouped into 25 phylotypes. Of these, six were affiliated with Firmicutes, Actinobacteria, and Verrucomicrobia, and were not found using our culture-dependent methods. Consequently, we believe that Marine agar and Zobell 2216 agar are optimal media for culturing diverse intestinal microbes; we also discovered several novel sequences not previously recognized as part of the gut microbiota of olive flounder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.687-692
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• 2010

The mass cultivation of Ecklonia cava Kjellman was studied as a potential biomass source for the extract industry in Korea. Experiments were conducted to investigate the optimal conditions for artificial seed production and mass cultivation of this species. Maximum growth and young thalli development in the nursery culture area occurred at 2 m depth, whereas maximum growth of thalli in the main culture area occurred at 1 m depth. Production of E. cava was between 2.6 and 3.6 kg wet wt. $m^{-1}$ after depth control and removal of fouling organism, etc. The relationship between optimal water depth for culture and underwater irradiance during the E. cava cultivation was calculated as: y = -0.718x + 8.042 ($r^2$=0.976). The growth rates achieved in this trial indicate that E. cava cultures could produce and supply sufficient biomass.

• Biomolecules & Therapeutics
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• v.12 no.3
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• pp.179-184
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• 2004

The FimH subunit of type 1-fimbriated Escherichia coli has been determined as a major cause for urinary tract infections. In our previous study, the Adhesin/CTXA2B was expressed as soluble recombinant chimaeric protein derived from the uropathogenic Escherichia coli adhesin genetically coupled to cholera toxin A2B (CTXA2B) subunit in Escherichia coli. Since it is very important to optimize IPTG concentration and culture temperature to maximize cell growth and productivity, These optimal culture factors were determined to increase the productivity of the expressed Adhesin/CTXA2B chimaeric protein in Escherichia coli TB1 carrying pMALfimH/ctxa2b. Our data demonstrate that optimal concentration of IPTG for increased production of chimaeric protein was 0.5 mM. Additionally, culture time was 10 hours and temperature, 37${\circ}C$.

• Textile Coloration and Finishing
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• v.12 no.1
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• pp.25-31
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• 2000

In order to decolorize disperse dyes by using biological treatment process, a strain which has potential ability to degrade disperse dyes was isolated from natural system. To increase the removal efficiency of decolorization in the aqueous solutions, the optimal condition of decolorization by this strain was investigated, and continuous plant test was also developed. The optimal culture conditions of temperature and pH were found to be 4$0^{\circ}C$ and 8.5~9, respectively. When yeast extract was mixed with polypeptone at the mixing ratio of 1:1 as a nitrogen source, decolorization efficiency was highest(93%) among the nitrogen sources. The strain to be screened was excellent to adjust to pH, and it seems to be have ability to control pH needed to growth. The optimal culture conditions in concentration of $MgSO_4\cdot{7H}_2O$ and $KH_2PO_4$ were 0.1%(w/v) and 0.2%(w/v). The result of continuous plant process using wastewater was as following : $COD_{Mn}$ removal efficiency was over than 50%, and this strain was very excellent in decolorization-efficiency for the wastewater of Taegu dyeing complex.

• The Korean Journal of Mycology
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• v.35 no.2
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• pp.76-80
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• 2007

This study was carried out to obtain basic data on mycelial growth characteristics for an artificial cultivation of Grifola frondosa. Ten strains of G. frondosa were collected from Korea, China and Japan and investigated its optimal culture condition. Among four kinds of mushroom culture media, PDA medium was selected as the suitable culture medium. The optimal conditions for the mycelial growth of G. frondosa in PDA medium were $25^{\circ}C$ and $4{\sim}5$ of pH, respectively. The carbon and nitrogen sources for the optimum mycelial growth were fructose and peptone, respectively, and the highest mycelial growth was observed when the C/N ratio was $10{\sim}20$.

• Research in Plant Disease
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• v.27 no.3
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• pp.99-106
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• 2021

The fungal isolate Isaria javanica pf185 has potential as a mycopesticide because it demonstrates insecticidal activity against the green peach aphid and antifungal activity against Colletotrichum gloeosporioides. For commercialization of this isolate, determination of the optimal and least expensive culture conditions is required; however, these data are not currently available. This study describes the conditions for optimal development of conidia and production of metabolites for the biocontrol of the fungal pathogen. The optimal culture conditions were examined using cultures on solid agar and liquid media. High growth temperature enhanced spore formation but reduced antifungal activity in both solid and liquid media. The highest spore yield was obtained in a medium containing glucose as a carbon source and yeast extract as a nitrogen source. Soybean powder and wheat bran were effective nitrogen sources that promoted spore production and antifungal activity of the isolate. These results revealed the basic, cost-effective growth media for commercial production of a biopesticide with insecticidal and antifungal properties for use in integrated pest management.

• Microbiology and Biotechnology Letters
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• v.2 no.1
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• pp.29-35
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• 1974

We have studied the applicability of the principles and inherent advantages of the two-stage dontinuous uclture technique to an enzyme process for the purpose of improving and optimizing the productivity of 3-ketosteroid-delta-1-dehydrogenase. By using a two-stage continuous culture system, the growth st ageand enzyme produdtion stage are separated. In each stage an optimal set of toperaing conditions was determined, and this was tested for feasibility for the period of 10 days. During this period, at least 70％ of the maximum enzyme productivity could be maintained. The important design parameters studied are: (1) optimal specific growth rate in the first stage which corresponds to the maximal cell productivity, (2) the optimal dilution rate in the second stage which in turn determines the size of second stage fermentor and the mean residence time of cells in the second stage, (3) cell concentration in both stages, add (4) the specific enzyme productivity and enzyme productivity of the second stage. In addition, by using two-stage continuous culture system we have been able to reduce or eliminate the effect of catabolite repression due to high medium concentration and the adverse effect of the solvent used to dissolve the inducer. We have found the balance between the opposing effects of induction and repression in the second stage judging from the observation that the enzyme productivity goes through a maximum.

• The Korean Journal of Mycology
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• v.49 no.1
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• pp.45-55
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• 2021

Artomyces microspora is a genus of coral fungi from the family Auriscalpiaceae that have sporophores which are clavarioid, profusely and pyxidately branched, and devoid of a conspicuous stipe. These fungi can be found in summer and fall. This study aimed to decipher fundamental information regarding optimal growth conditions of Artomyces microsporus mycelia, including pH, temperature, carbon sources, and nitrogen sources. Based on the assessment of colony diameter and mycelial density, the optimal culture medium, temperature, and pH for mycelial growth were found to be PDA, 25 ℃, and pH 5.0, respectively. Furthermore, the study revealed that the optimal carbon and nitrogen sources for mycelial growth were 1% soluble starch and 2% malt extract, respectively. The other suitable inorganic nitrogen sources were deemed to be 0.1% NH₄H₄PO₄ and 0.1% aspartic acid.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.385-390
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• 2009

To investigate the cellular growth traits of a photosynthetic green algae, Chlorella pyrenoidosa, several tests upon a culture temperature, a culture time, the influence of nutrient and the intensity of illumination were executed. Using growth chamber, some optimal conditions for the culture of algae were as follows: The culture temperature was about $28^{\circ}C$, the culture time about 4 days, and the cellular growth of algae was in proportioned to the concentration of nutrient such as nutrient broth. And the more the intensity of illumination was increased, the more the algal cell showed good growth. And then, the activity of enzyme degrading acetaldehyde was also studied using HPLC from the same strain. This enzyme was dependent on $\beta$-$NAD^+$. And showed its optimal pH around on 9.0, and also its optimal temperature around at $40^{\circ}C$. The operational conditions of HPLC were as follows: Column, ODS-Hypersil ; mobile phase, 50% (v/v) acetonitrile.