• Biotechnology and Bioprocess Engineering:BBE
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• 제10권3호
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• pp.192-197
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• 2005

The effects of macronutrients $(NO_3^-,\; NH_4^+\;and\;PO_4^{3-})$ on cell growth and triterpenoids production in Centella asiatica cell suspension cultures were analyzed using the Box­Behnken response surface model experimental design. In screening and optimization experiments, $PO_4^{3-}$ as a single factor significantly influenced cell growth where increasing the phosphate level from 0.1 to 2.4 or 2.6 mM, elevated cell growth from 3.9 to $14\~16g/L$. The optimum values predicted from the response surface model are 5.05mM $NH_4^+$, 15.0mM $NO_3^-$ and 2.6mM $PO_4^{3-}$, yielding 16.0g/L cell dry weight with $99\%$ fitness to the experimental data. While the $NH_4^+-NO_3^-$ interaction influenced cell growth positively in the optimization experiment, $NH_4^+$ and $NO_3^-$ as single factors; and interactions of $NO_3^--PO_4^{3-},\;NH_4^+-PO_4^{3-}$ and $NH_4^+-NO_3^-$ were all negative in the screening experiment. Cell growth and the final pH level were positively affected by $PO_4^{3-}$, but negatively affected by $NH_4^+\;and\;NH_4^+-PO_4^{3-}$ interactions. The different effects of factors and their interactions on cell growth and final pH are influenced by a broad or narrow range of macronutrient concentrations. The productions of triterpenoids however were lower than 4mg/g cell dry weight.

• Journal of Microbiology and Biotechnology
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• 제19권7호
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• pp.685-689
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• 2009

We describe the expression of recombinant canstatin from stably transformed Bombyx mori BmS (BmS) cells. Recombinant canstatin was secreted into a culture medium with a molecular mass of approximately 29 kDa. Densitometric scanning showed that the secreted canstatin accounted for approximately 91% of the total canstatin production. Recombinant canstatin was also purified to homogeneity using a simple one-step Ni-NTA affinity fractionation. The identity of the purified protein was confirmed as human canstatin by nano-LC-MS/MS analysis. Purified recombinant canstatin inhibited human endothelial cell proliferation in a dose-dependent manner. The concentration at half-maximum inhibition ($ED_{50}$) for recombinant canstatin expressed in stably transformed BmS cells was approximately 0.64 ${\mu}g/ml$. A maximum production level of 11 mg/l recombinant canstatin was obtained in a T-flask culture of BmS cells after 6 days of incubation.

• The Plant Pathology Journal
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• 제26권2호
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• pp.170-177
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• 2010

Bacillus licheniformis N1, previously developed as a biofungicide formulation N1E to control gray mold disease of plants, was investigated to study the bacterial traits that may be involved in its biological control activity. Two N1E based formulations, bacterial cell based formulation PN1E and culture supernatant based formulation SN1E, were evaluated for disease control activity against gray mold disease of tomato and strawberry plants. Neither PN1E nor SN1E was as effective as the original formulation N1E. Fractionation of antifungal compounds from the bacterial culture supernatant of B. licheniformis N1 indicated that two different cyclic lipopeptides were responsible for the antimicrobial activity of the N1 strain. These two purified compounds were identified as iturin A and surfactin by HPLC and LCMS. The purified lipopeptides were evaluated for plant disease control activity against seven plant diseases. Crude extracts and purified compounds applied at 500 ${\mu}g/ml$ concentration controlled tomato gray mold, tomato late blight and pepper anthracnose effectively with over 70% disease control value. While iturin showed broad spectrum activity against all tested plant diseases, the control activity by surfactin was limited to tomato gray mold, tomato late blight, and pepper anthracnose. Although antifungal compounds from B. licheniformis N1 exhibited disease control activity, our results suggested that bacterial cells present in the N1E formulation also contribute to the disease control activity together with the antifungal compounds.

• 한국잡초학회지
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• 제15권2호
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• pp.148-153
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• 1995

Glyphosate (N-[phosphonomethyl]glycine)를 토마토(Lycopersicon esculentum Mil)의 동화부위(同化部位)에 부분처리(部分處理)하거나 전(全) 식물체(植物體)에 분무처리(噴霧處理)하였을 때 EPSP-synthase의 활성(活性) 감소(減少)가 나타났다. EPSP-synthase의 활성(活性)은 처리된 식물체(植物體)의 엽록소(葉綠素)의 감소보다 시기적으로 먼저 나타나는 현상이었다. EPSP-synthase의 활성(活性)은 glyphosate처리(處理)에 민감한 효소(酵素)로서 토마토의 세포현탁배양조직(細胞顯濁培養組織)과 분열조직(分裂組織)간에는 활성(活性)의 차이가 없없다. EPSP-synthase의 활성은 4-6 nkat/mg protein 정도이었다. EPSP-synthase의 활성(活性)억제는 glyphosate 처리(處理) 36시간 후 부터 나타나기 시작하였고, 엽록소(葉綠素)의 감소는 처리 48 시간 후 부터 나타나기 시작하였다. 세포현탁배양(細胞顯濁培養)에서 치사농도(致死濃度) 이하(以下)에서 glyphosate는 생체중(生體重)을 저하(低下)시켰으며 생육단계(生育段階) 중 lag-phase를 연장(延長)시켜 생육(生育)이 더디도록 하였다. Glyphosate 존재(存在)하에서 생체중(生體重)은 계대(繼代)배양 후 14일이 지난 뒤에 생체중(生體重)이 최고(最高)에 달하였다. EPSP-synthase에 대한 gly-phosate의 억제(抑制)효과는 lag-phase에서 심하게 나타났다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권5호
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• pp.442-448
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• 2006

Human lactoferrin (hLf) is an iron-binding glycoprotein that has been considered to play many biological roles in the human, including the stimulation of the immune system, antimicrobial and anti-inflammatory effects, and regulation of iron absorption. We generated transgenic Siberian ginseng (Acanthopanax senticosus) cell cultures producing a functional hLf protein using the signal peptide sequence from the endoplasmic reticulum and driven by an oxidative stress-inducible SWPA2 promoter which is highly expressed in plant cell cultures. The production of hLf increased proportionally to cell growth and showed a maximal level (up to 3.6% of total soluble protein) at the stationary phase in suspension cultures. Full-length hLf protein was identified by immunoblot analysis in transgenic cell cultures of Siberian ginseng. Recombinant hLf (rhLf) was purified from suspension cells of Siberian ginseng by ammonium sulfate precipitation, cation-exchange and gel filtration chromatography. N-terminal sequences of rhLf were identical to native hLf (nhLf). The overall monosaccharide composition of rhLf showed the presence of plant specific xylose while sialic acid is absent. Antibacterial activity of purified rhLf was higher than that of nhLf. Taken together, we anticipate that medicinal Siberian ginseng cultured cells, as demonstrated by this study, will be a biotechnologically useful source for commercial production of functional hLf not requiring further purification.

• Journal of Plant Biotechnology
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• 제37권3호
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• pp.243-249
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• 2010

Molecular farming is production of pharmaceutically and industrially important proteins in plants. Plants and plant cell culture systems have been used as bio-factory to produce recombinant proteins such as monoclonal antibodies, enzymes, vaccines, hormones, interleukins, commercial enzymes and etc. The terms molecular farming, biofarming, molecular pharming, phytomanufacturing, recombinant or plant-made industrials, planta-pharma, plant bioreactors, plant biofactory, and pharmaceutical gardening are used interchangeably. Molecular farming can provide safe and inexpensive pharmaceutical proteins as well as commercial ones. In spite of several advantages of molecular farming such as safety and inexpensive cost, there are also a couple of drawbacks in the existing technology. One of them is low expression level of target gene in plants, which has been improved by optimizing gene-based codon usage, screening of strong promoters, expression of transcription factors, subcellular targeting of target proteins, chloroplast transformation, and transient expression using viral expression system (magnifection). Some plant-based commercial proteins have already been in markets and more than twenty plant-based pharmaceuticals have been in clinical trials, from that we can expect that several plant-based pharmaceutical proteins will be seen in the markets in the near future.

• Food Science and Biotechnology
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• 제16권4호
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• pp.632-635
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• 2007

This study examined the neuroprotective effect of scopoletin from Angelica dahurica against oxygen and glucose deprivation-induced neurotoxicity in a rat organotypic hippocampal slice culture. Scopoletin reduced the propidium iodide (PI) uptake, which is an indication of impaired cell membrane integrity. In addition, it inhibited the loss of NeuN, which represents the viability of neuronal cells. The results suggests that scopoletin from A. dahurica protects neuronal cells from the damage caused by oxygen and glucose deprivation.

• 식물조직배양학회지
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• 제27권4호
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• pp.259-268
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• 2000

Senescence is a sequence of biochemical and physiological events that lead to death of a cell, organ, or whole organism. Senescence is now clearly regarded as a genetically determined and evolutionarilly acquired developmental process comprising the final stage of development. However, in spite of the biological and practical importance, genetic mechanism of senescence has been very limited. Through forward and reverse genetic approaches, we are trying to reveal the molecular and genetic mechanism of senescence in plants, employing leaf organs of Arabidopsis as a model system. Using forward genetic approach, we have initially isolated several delayed senescence mutants either from T-DNA insertional lines or chemical-mutagenized lines. In the case of ore 4 and ore 9 mutants, the mutated genes were identified. The recent progress on characterization of mutants and identification of the mutated genes will be reported. We are also screening mutations from other various sources of mutant pools, such as activation tagging lines and promoter trap lines. Two dominant senescence-delayed mutants were isolated from the activation tagging pool. Cloning of the genes responsible for this phenotype is in progress. For reverse genetic approach, the genes that induced during leaf senescence were first isolated by differential screening method. We are currently using PCR-based suppression subtractive hybridization, designed to enrich a cDNA library for rare differentially expressed transcripts. Using this method, we have identified over 35 new sequences that are upregulated at leaf senescence stage. We are investigating the function of these novel genes by systemically generating antisense lines.

• 한국자원식물학회지
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• 제29권3호
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• pp.289-296
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• 2016

This study was executed to evaluate the immune activity, nitrite scavenging activity and ABTS radical scavenging activity against extracts of various concentration of ethanol solvent from Codonopsis lanceolata cultured at 6 local regions. The immune responses from both human T and B cell line was significantly enhanced in the cell growth compared to control while the cell growth was influenced at a certain period of culture. The results revealed that the cell growth of both human T and B cell was altered in a time dependent manner. The nitrite scavenging activity of ethanol extracts from various solvent concentration of C. lanceolata were affected by pH. At a pH of 1.2, the nitrite scavenging effect of all of the extracts tested observed higher than that of the other two pH ranges. There was no distinct detection of nitrite scavenging effects of the pH range 6.0. The ABTS radical scavenging activity was progressively increased in a dose-dependent manner, and the activity was the highest in 100% ethanol extract. The result from this investigation suggests that the extract of Codonopsis lanceolata could be an addition to basic medicine for immune modulation and natural food additives.

• 문화기술의 융합
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• 제7권4호
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• pp.721-726
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• 2021

식물 세포는 각 세포가 발생을 통해 새로운 완전한 개체를 생산하는 전형성능이 있다. 이것을 응용하여 식물의 증식 방법으로 기내에서 호르몬을 처리하여 체세포 배 발생의 광범위한 적용으로 여러 기술이 발전하고 있다. 이 기술을 이용하기 위해서 보다 규칙적인 세포 분열을 하는 무성생식이 가능한 식물인 Kalanchoe pinnata 에 cytokinin에 속하는 kinetin과 auxin에 속하는 호르몬들 중 picloram을 서로 조합하여 첨가한 뒤 8주 동안 처리한 후 전형성능을 실험하였다. 우리의 실험 결과로 잎 절편에서 발근 효과로는 picloram 농도가 0.1 mg/L에서 70%의 발생율을 보였다. kinetin과 picloram의 비율이 1:5-1:10의 농도차이가 효과적이라는 것이 입증 되었다. auxin의 효과가 Kalanchoe 뿌리 발생에 필수적이라는 실험 결과이다. 경엽부 발생 효과로는 picloram 농도가 0.5 mg/L에서 60%의 발생율을 보였다. kinetin 농도는 0.5 - 1.0 mg/L이며 발생에 중요한 영향을 준다. kinetin과 picloram의 비율이 1:1-1:2의 농도 차이가 효과적이라는 것이 입증 되었다. cytokinin과 auxin의 조합이 결정적으로 경엽부 발생에 중요하다는 것을 보여 주는 결과이다. 호르몬의 조합으로 직접기관형성을 유도하여 기내에서 대량 증식을 유도하는 기술의 기초가 될 수 있다고 사료된다.