• Biotechnology and Bioprocess Engineering:BBE
• /
• v.10 no.6
• /
• pp.528-534
• /
• 2005

Hairy root cultures have demonstrated great promise in terms of their biosynthetic capability toward the production of secondary metabolites, but continue to constitute a major challenge with regard to large-scale cultures. In order to assess the possibility of conducting mass production of biomass, and the extraction of useful metabolites from Panax ginseng. P. ginseng hairy roots, transformed by Rhizobium rhizogenes KCTC 2744, were used in bioreactors of different types and sizes. The most effective mass production of hairy roots was achieved in several differently Sized air bubble bioreactors compared to all other bioreactor types. Hairy root growth was enhanced by aeration, and the production increased with increasing aeration rate in a 1 L bioreactor culture. It was determined that the hairy root growth rate could be substantially enhanced by increases in the aeration rate upto 0.5vvm, but at aeration rates above 0.5vvm, only slight promotions in growth rates were observed. In 20 L air bubble bioreactors, with a variety of inoculum sizes, the hairy roots exhibited the most robust growth rates with an inoculum size of 0.1% (w/v), within the range 0.1 to 0.7% (w/v). The specific growth rates of the hairy root decreased with increases in the inoculum size.

• Journal of Plant Biotechnology
• /
• v.6 no.4
• /
• pp.265-268
• /
• 2004

Cell growth and ginseng saponin production by large-scale suspension (bioreactor) cultures of Panax ginseng were investigated under various inoculum sizes. Cell growth was low at an inoculum size of 40 g FW/L, and the maximum cell growth was obtained with increasing inoculum size up to 100 g FW/L. The cell density of 333 g FW/L and 12.7 g DW/L was obtained at inoculum size of 100 g FW/L after 30 days of cultivation. Maximum saponin production of $4.40\;\cal{mg/g}$ DW was achieved at 60 g FW/L of inoculum size. Thus, inoculum size 60 g FW/L was suitable for optimum biomass accumulation as well as saponin production during bioreactor cultivation of ginseng suspension cells.

• Journal of Microbiology and Biotechnology
• /
• v.32 no.8
• /
• pp.1054-1063
• /
• 2022

Trehalose is a non-conventional sugar with potent applications in the food, healthcare and biopharma industries. In this study, trehalose was synthesized from maltose using whole-cell Pseudomonas monteilii TBRC 1196 producing trehalose synthase (TreS) as the biocatalyst. The reaction condition was optimized using 1% Triton X-100 permeabilized cells. According to our central composite design (CCD) experiment, the optimal process was achieved at 35℃ and pH 8.0 for 24 h, resulting in the maximum trehalose yield of 51.60 g/g after 12 h using an initial cell loading of 94 g/l. Scale-up production in a lab-scale bioreactor led to the final trehalose concentration of 51.91 g/l with a yield of 51.60 g/g and productivity of 4.37 g/l/h together with 8.24 g/l glucose as a byproduct. A one-pot process integrating trehalose production and byproduct bioremoval showed 53.35% trehalose yield from 107.4 g/l after 15 h by permeabilized P. moteilii cells. The residual maltose and glucose were subsequently removed by Saccharomyces cerevisiae TBRC 12153, resulting in trehalose recovery of 99.23% with 24.85 g/l ethanol obtained as a co-product. The present work provides an integrated alternative process for trehalose production from maltose syrup in bio-industry.

• International Journal of Advanced Culture Technology
• /
• v.3 no.2
• /
• pp.100-109
• /
• 2015

Environmental problems from petroleum-based plastic wastes have been rapidly increasing in recent years. The alternative solution is focus on the development of environmental friendly plastic derived from renewable resource. Poly(lactic acid) (PLA) is a biodegradable polymer synthesized from biomass having potential to replace the petroleum-based non-degradable polymers utilizations. PLA can be synthesized by two methods: (1) ring-opening of lactide intermediate and (2) direct polycondensation of lactic acid processes. The latter process has advantages on high yields and high purity of polymer products, materials handling and ease of process treatments. The polymerization process of PLA synthesis has been widely studied in a laboratory scale. However, the mass scale production using direct polycondensation of lactic acid has not been reported. We have investigated the kinetics and scale-up process of direct polycondensation method to produce PLA in a pilot scale. The order of reaction is 2 and activation energy of lactic acid to lactic acid oligomers is 61.58 kJ/mol. The pre-polymer was further polymerized in a solid state polymerization (SSP) process. The synthesized PLA from both the laboratory and pilot scales show the comparable properties such as melting temperature and molecular weight. The appearance of synthesized PLA is yellow-white solid powder.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.83-84
• /
• 2009

Thin film solar cells based on CIGS continue to be a leading candidate for thin film photovoltaic devices due to their appropriate bandgap, long-term stability, and low-cost production. To date, the most successful technique for the deposition of a CIGS absorber layer has been based on the co-evaporation However, the evaporation process is difficult to scale-up for large-area manufacturing the sputtering and Selenizaton process has been a promising method for low-cost and large-scale production of high quality CIGS In this study, we have used Cu and CuIn alloy targets for precursor deposition the precursor deposited by sputtering Cu and CuIn targets and $CuInSe_2$ thin film is manufactured by Selenization process

• KSBB Journal
• /
• v.9 no.4
• /
• pp.378-384
• /
• 1994

An improved method for the selective isolation of high-yielding mutant strains for the production of antifungal antibiotic KRF-001 was investigated. The mutant strain U. V 4, which produces high titer of KRF-001, was selected on the high potency agar plate after ultraviolet light irradiation. The U. V 4 strain produced 2-fold more KRF-001 than the mother strain in production media. Large scale fermentation was performed using the U. V 4 strain in 100$\ell$ fermenter. The antifungal antibiotic KRF-001 secreted into culture broth was detected by HPLC in 24hrs of fermentation.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.35 no.2
• /
• pp.111-117
• /
• 2017

Mulberry leaves containing 1-deoxynojirimycin (DNJ) known to be a strong inhibitory effect for ${\alpha}-glucosidase$. Thus, DNJ has been recognized as a potentially important source for prevent or treat hyperglycemia. More effective method for the DNJ high-production is needed because DNJ content of natural mulberry leaf are as low as 0.1%. Many researchers have studied for the DNJ high-production in mulberry leaves such as the harvest season, fermentation using microorganisms, optimal culture conditions, and optimal extraction conditions. In order to provide for useful data that is anticipated at the level of industrial scale, we investigated ${\alpha}-glucosidase$ inhibitory activity, pH value and DNJ content in large-scale based on the optimal culture conditions for mulberry leaf fermentation of small-scale in our previous study. The ${\alpha}-glucosidase$ inhibitory activity, pH value, and DNJ content in this study were measured from the mulberry leaf fermentation broth for 7 days. During mulberry leaf fermentation, the ${\alpha}-glucosidase$ inhibitory activity and DNJ content was increased until 2 to 4 days, but after 4 day was decreased. The pH value showed a decreasing trend up to 2 day, and little changes in 2 to 4 days. However, the pH was started to increase after 4 days.

• Journal of Embryo Transfer
• /
• v.6 no.2
• /
• pp.18-29
• /
• 1991

Nuclear transplantation technique is known as the most potential and efficient method for producing a large number of genetically identical animals from a single embryo. The technical development of nuclear transplantation in mammals and its application to the production of cloned animals are described. For the efficient and successful production of cloned embryos by nuclear transplantation, the right selection and micromanipulation of recipient eggs or embryos as capacious recipient cytoplasm, the adequate and benefitlal preparation of multiple totipotent embryonic cells as donor nuclei, and also the fusion technique are very critical. Recent studies approaching to these critical points are introduced and discussed. Up to date, the overall efficiency of production of cloned embryos and offspring in livestock is estimated to be low. Further technical development of nuclear transplantation will enable large-scale production of cloned livestock and in near future the commercial cloning of animals will become a reality.

• Journal of Life Science
• /
• v.15 no.1 s.68
• /
• pp.15-20
• /
• 2005

The unstructured model was tested to describe mycelial growth, exopolysaccharide formation, and substrate consumption in submerged mycelial culture of Paeeiliomyees tenuipes C240. The Logistic equation for mycelial growth, the Luedeking-Piret equation for exopolysaccharide formation, and Luedeking­Piret-like equations for glucose consumptions were successfully incorporated into the model. The value of the key kinetic constants were: maximum specific growth rate ${\mu}m,\;0.7281\;h^{-1};$ growth­associated constant for exopolysaccharide production $(\alpha),\;0.1743g(g\;cells)^{-1}$; non-growth associated constant for exopolysaccharide production $(\beta),\;0.0019g(g\;cells)^{-1}\;;$ maintenance coefficient $(m_s),\;0.0572g\;(g\;cells)^{-1}$. When compared with batch experimental data, the model successfully provided a reasonable description for each parameter during the entire growth phase. The model showed that the production of exopolysaccharide in P. tenuipes C240 was growth-associated. The model tested in the present study can be applied to the design, scale-up, and control of fermentation process for other kinds of basidiomycetes or ascomycetes.

• The Journal of the Korea Contents Association
• /
• v.13 no.12
• /
• pp.357-368
• /
• 2013

This research explores the efficiency of social welfare expenditure in Korea by analyzing marginal productivity, scale economies, and elasticity of substitution that could be obtainable from a production function. By virtue of VES production function, such productive indicators are easily identified. If once the efficiency is revealed in the production process, it brings to a positive impact to increase the level of income. Empirical evidences are shown that the public expenditure is operated systematically in comparing with the private one. This is mainly due to the fact that the system of the public sector is well-established. It implies that an operational system for the private sector ought to be built up in a short period of time. Otherwise, increasing in expenditure by a private sector would not be helpful to improve efficiency in the production side. Accordingly, level of income.