• Journal of Microbiology and Biotechnology
• /
• 제3권4호
• /
• pp.238-243
• /
• 1993

In the suspension cultures of Eschscholtzia californica, phytohormone effects showed that alkaloid production was increased by IAA treatment without kinetin in both volumetric and specific way. Kinetin, however, suppressed alkaloid accumulation. Addition of ethephon inhibited cell growth. However, it enhanced the alkaloid production significantly in both volumetric and specific way. IAA promoted alkaloid production during elicitation. The highest alkaloid accumulation was observed at 5 $\mu$ M of IAA. Ethephon also enhanced alkaloid production during elicitation. The highest alkaloid formation was observed at 460 mg/l of ethephon with elicitation. Elicitation with ethephon, however, altered cell growth and the pattern of benzophenanthridine alkaloids production.

• KSBB Journal
• /
• 제15권6호
• /
• pp.609-614
• /
• 2000

최근 항암제로서 관심을 끌고있는 camptothecin올 생산하기 위한 희수(Camptotheca acuminata) 현탁세포 배양과 cam­p ptothecin의 생산을 촉진하는 연구를 수행하였다. 장기간 배양 으로 발생되는 이차대사산물 생산능력의 변이가 관찰되어 이 를 극복하고자 세포의 응집을 통한 camptothecin의 생산을 촉진하고자 하였다. 세포의 응집은 hybrid 배지와 sucrose 4 %일 때에 가장 많이 유도되었고, 이때 camptothecin의 생산량도 $18.04{\times}10^{-4} mg/L$로 가장 높은 생산성을 가졌다. 또한, 세포의 응집을 유도하기 위한 일환으로 교반속도를 변화시켜 이에 대한 효과를 알아보았는데, 100rpm에서 가장 많은 세포응집이 유도되었으며, camptothecin의 생산 역시 $19.4{\times}10^{-4} mg/L$로 가장 높은 결과를 나타내었다.

• Journal of Ginseng Research
• /
• 제36권1호
• /
• pp.61-67
• /
• 2012

In the present study, effects of sun ginseng (SG) on the collagen synthesis and the proliferation of dermal fibroblast were investigated. Collagen synthesis was measured by assaying procollagen type I C-peptide production. In addition, the level of matrix metalloproteinase (MMP)-1 was assessed by western blot analysis. SG suppressed the MMP-1 protein level in a dose-dependent manner. In contrast, SG dose-dependently increased tissue inhibitors of MMP (TIMP)-1 production in fibroblasts. SG increased type I collagen production directly and/or indirectly by reducing MMP-1 and stimulating TIMP-1 production in human dermal fibroblasts. SG dose-dependently induced fibroblast proliferation and this, in turn, can trigger more collagen production. These results suggest that SG may be a potential pharmacological agent with anti-aging properties in cultured human skin fibroblast.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
• /
• pp.338-341
• /
• 2000

An internal membrane bioreactor system was employed for continuous succinic ac id production from glucose in order to prove its performance and practicality. Succinic acid-producing Anaerobiospirillum succiniciproducens required more $CO_2$ for the proper growth and succinic acid production in cell recycled continuous culture than in batch culture. The maximum productivity obtained in cell recycled continuous culture was about 3.3 g/L-h which was ca. 3.3 times higher than that obtained in batch culture.

• IMMUNE NETWORK
• /
• 제3권3호
• /
• pp.188-200
• /
• 2003

Background: Immunization of dendritic cells (DCs) pulsed with tumor antigen can activate tumor-specific cytotoxic T lymphocytes (CTL) that are responsible for protection and regression. In this study, we examined whether the uptake of necrotic tumor cells could modulate DC phenotypes and whether the immunization of necrotic tumor cell-loaded DCs could elicit efficient tumor specific immune responses followed by a regression of established tumor burdens. Methods: We prepared necrotic tumor cell-pulsed DCs for the therapeutic vaccination and investigated their phenotypic characteristics, the immune responses induced by these DCs, and therapeutic vaccine efficacy against colon carcinoma in vivo. Several parameters including phagocytosis of tumor cells, surface antigen expression, chemokine receptor expression, IL-12 production, and NK as well as CTL activation were assessed to characterize the immune response. Results: DCs derived from mouse bone marrow efficiently phagocytosed necrotic tumor cells and after the uptake, they produced remarkably increased levels of IL-12. A decreased CCR1 and increased CCR7 expression on DCs was also observed after the tumor uptake, suggesting that antigen uptake could induce DC maturation. Furthermore, co-culturing of DCs with NK cells in vitro enhanced IL-12 production in DCs and IFN-${\gamma}$ production in NK cells, which was significantly dependent on IL-12 production and cell-to-cell contact. Immunization of necrotic tumor cell-loaded DCs induced cytotoxic T lymphocytes as well as NK activation, and protected mice against subsequent tumor challenge. In addition, intratumoral or contra-lateral immunization of these DCs not only inhibited the growth of established tumors, but also eradicated tumors in more than 60% of tumor-bearing mice. Conclusion: Our data indicate that production of IL-12, chemokine receptor expression and NK as well as CTL activation may serve as major parameters in assessing the effect of tumor cell-pulsed DC vaccine. Therefore, DCs loaded with necrotic tumor cells offer a rational strategy to treat tumors and eventually lead to prolonged survival.

• 한국수소및신에너지학회논문집
• /
• 제20권5호
• /
• pp.416-423
• /
• 2009

High-temperature steam electrolysis (HTSE) using solid oxide cell is a challenging method for highly efficient large-scale hydrogen production as a reversible process of solid oxide fuel cell (SOFC). The overall efficiency of the HTSE hydrogen and synthesis gas production system was analyzed thermo-electrochemically. A thermo-electrochemical model for the hydrogen and synthesis gas production system with solid oxide electrolysis cell (SOEC) and very high temperature gas-cooled reactor (VHTR) was established. Sensitivity analyses with regard to the system were performed to investigate the quantitative effects of key parameters on the overall efficiency of the production system. The overall efficiency with SOEC and VHTR was expected to reach a maximum of 58% for the hydrogen production system and to 62% for synthesis gas production system by improving electrical efficiency, steam utilization rate, waste heat recovery rate, electrolysis efficiency, and thermal efficiency. Therefore, overall efficiency of the synthesis production system has higher efficiency than that of the hydrogen production system.

• Journal of Microbiology and Biotechnology
• /
• 제8권1호
• /
• pp.8-13
• /
• 1998

Animal cells in culture typically convert most of the glucose they consume into lactate. The accumulation of lactate, however, is commonly cited as one of the factors that inhibit cell growth and limit the maximum cell concentration that can be achieved in culture. The specific production of lactate and the amount of glucose converted to lactate can be reduced when cells are grown in a fed-batch culture in which the residual glucose concentration is maintained at low levels. Such a fed-batch culture was used to grow and adapt hybridoma cells into a low-lactate-producing state before changing into continuous culture. The cells reached and maintained a high viable cell concentration at steady state. In a similar manner, cells that were initially grown in batch culture and a glucose-rich environment reached a steady state with a cell concentration that is much lower. The feed composition and dilution rates for both cultures were similar, suggesting steady state multiplicity. From a processing perspective the desired steady state among those is the one with the least metabolite production. At such seady state nutrient concentration in the feed can be further increased to increase cell and product concentrations without causing the metabolite inhibitory effect typically seen in a cell culture. Controlling cell metabolism in a continuous culture to reduce or eliminate waste metabolite production may significantly improve the productivity of mammalian cell culture processes.

• 한방안이비인후피부과학회지
• /
• 제22권1호
• /
• pp.108-119
• /
• 2009

Objectives : This study was carried out to investigate the effects of Samhwangseje(SHSJ) on anti-Inflammation in Raw 264.7 cell. Methods : The effects of SHSJ on anti-Inflammation were measured by the cytotoxicity of Raw 264.7 cell, the inhibition for NO, TNF-$\alpha$, $PGE_{2}$, iNOS and COX-2, the blocking NF-${\kappa}B$ into nucleus. Results : 1. All concentrations of SHSJ had no cytotoxicity in Raw 264.7 cell. 2. All concentrations of SHSJ inhibited the production of NO in the Raw 264.7 cell stimulated with LPS. 3. All concentrations of SHSJ did not inhibit the production of TNF-$\alpha$ in the Raw 264.7 cell stimulated with LPS. 4. All concentrations of SHSJ inhibited the production of $PGE_{2}$ in the Raw 264.7 cell stimulated with LPS. 5. All concentrations of SHSJ did not inhibit the expression of COX-2 but concentrations of 50 ${\mu}g/ml$, 100 ${\mu}g/ml$ SHSJ inhibited iNOS expression in the Raw 264.7 cell stimulated with LPS. 6. Concentrations of 50 ${\mu}g/ml$, 100 ${\mu}g/ml$ SHSJ had the effect of blocking NF-${\kappa}B$ into nucleus in LPS-induced macrophage Raw 264.7 cell.

• Journal of Microbiology and Biotechnology
• /
• 제8권5호
• /
• pp.478-483
• /
• 1998

For the enhanced production of a cardiac glycoside, digoxin, using in situ adsorption by biotransformation from digitoxin in plant cell suspension cultures, selection of proper resins was attempted and the culture conditions were optimized. Among various kinds of resins tested, Amberlite XAD-8 was found to be the best for digoxin production in considering adsorption characteristics as well as the effect on cell growth. Adequate time for resin addition was determined to be 36 h from the beginning of biotransformation and the presence of resins should be as short as possible to increase the productivity. In addition, to prevent the cells from direct contact with resin particles, immobilized systems were designed and examined. Immobilization further improved the advantages of in situ adsorption. It was confirmed that the increase of the contact area for mass transfer was an important factor in utilizing an immobilized system to enhance digoxin production.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2001년도 추계학술발표대회
• /
• pp.418-421
• /
• 2001

The gellan was produced by Pseudomonas elodea ATCC 31461 under aerobic condition. Gellan provides various functionalities such as gelling, suspending, stabilizing, emulsifying and binding properties in aqueous systems. In this study, the effect of glucose concentration and nitrogen sources concentration, bacto peptone and $NH_4NO_3$, on the cell growth and the production of gellan were evaluated. The maximum specific yield (g gellan/g cell) of 2.22 was obtained at 1.0% of glucose. Bacto peptone increased cell growth. And nitrogen limitation was essential for higher production of gellan. The highest cell and gellan production were abtained at 0.5 g/${\ell}$ of bacto peptone without $NH_4NO_3$.