• 농약과학회지
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• 제9권4호
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• pp.437-441
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• 2005

본 연구는 국내토착 토양세균인 Pasteuria penetrans 내생포자의 처리방법에 따른 땅콩뿌리혹선충(Meloidogyne arenaria) 방제효과를 파악하고자 수행하였다. 이를 위해 P. penetrans 내생포자의 농도($3{\times}10^4$, $3{\times}10^5$ 및 $3{\times}10^6$ endospores/5 g medium)별로 500마리 땅콩뿌리혹선충에 각각 부착한 후 기주식물인 토마토 뿌리에 접종하여 14주 후 뿌리에 형성된 뿌리혹 개체 수로 농도에 따른 선충방제 효과를 파악하였다. 그 결과 80%이상 방제효과를 보인 $3{\times}10^5$ 수준의 P. penetrans 내생포자를 500마리의 선충만을 접종한 토양과 혼합하여 처리한 시험구(토양혼화처리)와 토양표면에 처리한 시험구(토양표면처 리)로 구분하여 방제효과를 비교하였다. 이 중 방제효과가 높았던 토양혼화처리 방법을 이용하여 P. penetrans와 일본 상품인 $PASTORIA^{(R)}$그리고 국내에 등록된 살선충제인 선충탄(fosthiazate)과의 방제효과를 상호 비교하였다. 실험결과 P. penetrans의 농도가 높고 토양과 혼합하여 처리할 시 방제효과가 높았으며, P. penetrans 처리가 일본 제품보다는 우수한 방제효과를 보였고 국내 시판 화학방제제와는 유사하였다.

• 환경생물
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• 제20권2호
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• pp.130-135
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• 2002

PDA배지에서 $25^{\circ}C$로 배양할 때 초기 균사의 색은 흰색을 띄고 있었으며 배양 후기에 생성되는 포자의 색은 짙은 푸른색을 나타내고 있었다. 시간당 성장률은 1.1mm보다 빠른 것으로 나타났으며 성숙한 포자의 모양은 부드럽고 구형에 가까운 모양이었다. 이러한 형태학적 결과는 시간당 성장률이 0.5-0.7mm 이하인 Tricho-derma viride 및 T. hamatum의 특징과 성숙 포자의 모양이 실린더 모양인 T. koningii, T longibrachiatum과 구별되는 결과였다(Raifai 1969; Seaby 1996; Gams and Bissett 1998). 또한 Trichoderma harzianum의 분류에 있어 가장 중요한 구조는 phialospore의 형태가 구형이어야 하며, 포자의 겉은 부드럽고 크기는 $2.5-3.0\times{3.4-4.0}\mu{m}$ 정도인 것이 특징이다(Morris and Doyle 1995a, b). 이러한 결과를 종합하여 분리 균주를 동정한 결과 Trichoderma harzianum으로 확인할 수 있었다. Phytophthora capsici에 대한 분리 균주의 성장저해정도를 측정한 결과 $27^\circ{C}$의 조건에서 가장 높은 길항력을 나타내었으며 다른 곰팡이에 대한 성장억제도 이 온도에서 가장 높을 것으로 판단되었다. 또한 $31^\circ{C}$ 이상에서는 T. harzianum SJG-99721의 성장 속도가 급속히 떨어짐을 확인한 바 이러한 성질을 이용하여 느타리버섯의 균사 배양시 고온 배양을 실시할 경우 푸른곰팡이 병 오염을 극히 제한할 수 있을 것으로 판단되었다. 또한 이러한 고온에서의 성장 속도 제한은 식물 병원성 미생물과의 길항 작용에서도 영향을 미치는 만큼 생물농약으로서의 사용은 토양 온도가 $30^\circ{C}$ 넘지 않는 기간에 최대한 토양 내에서 증식이 이루어지도록 조처해야 한다. 진균성 식물 병원균의 세포벽 분해효소인 extracellular chitinase의 높은 활성도를 확인함으로서 Trichoderma harzianum SJG-99721의 강력한 식물 병원균 제어능력은 이들의 높은 chitinase의 활성도에 의한 것으로 유추할 수 있었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.68-68
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• 2018

In this study, we investigated whether S. baicalensis rhizome ethanol extract (SBRE) has antioxidant capacities against oxidative stress induced cellular damage in the HaCaT keratinocytes. Our results revealed that treatment with SBRE prior to hydrogen peroxide ($H_2O_2$) exposure significantly increased the HaCaT cell viability. SBRE also effectively attenuated $H_2O_2$ induced comet tail formation, and inhibited the $H_2O_2$ induced phosphorylation levels of the histone ${\gamma}H2AX$, as well as the number of apoptotic bodies and Annexin V positive cells. In addition, SBRE exhibited scavenging activity against intracellular ROS generation and restored the mitochondria membrane potential loss induced by $H_2O_2$. Moreover, $H_2O_2$ enhanced the cleavage of caspase-3 and degradation of poly (ADP-ribose)-polymerase as well as DNA fragmentation; however, these events were almost totally reversed by pretreatment with SBRE. Furthermore, SBRE increased the levels of HO-1 associated with the induction of Nrf2. Therefore, we believed that SBRE may potentially serve as an agent for the treatment and prevention of neurodegenerative diseases caused by oxidative stress.

• Molecules and Cells
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• 제43권3호
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• pp.222-227
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• 2020

Inositol polyphosphate multikinase (IPMK) is required for the biosynthesis of inositol phosphates (IPs) through the phosphorylation of multiple IP metabolites such as IP3 and IP4. The biological significance of IPMK's catalytic actions to regulate cellular signaling events such as growth and metabolism has been studied extensively. However, pharmacological reagents that inhibit IPMK have not yet been identified. We employed a structure-based virtual screening of publicly available U.S. Food and Drug Administration-approved drugs and chemicals that identified the antidepressant, vilazodone, as an IPMK inhibitor. Docking simulations and pharmacophore analyses showed that vilazodone has a higher affinity for the ATP-binding catalytic region of IPMK than ATP and we validated that vilazodone inhibits IPMK's IP kinase activities in vitro. The incubation of vilazodone with NIH3T3-L1 fibroblasts reduced cellular levels of IP5 and other highly phosphorylated IPs without influencing IP4 levels. We further found decreased Akt phosphorylation in vilazodone-treated HCT116 cancer cells. These data clearly indicate selective cellular actions of vilazodone against IPMK-dependent catalytic steps in IP metabolism and Akt activation. Collectively, our data demonstrate vilazodone as a method to inhibit cellular IPMK, providing a valuable pharmacological agent to study and target the biological and pathological processes governed by IPMK.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.76-76
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• 2020

Stachys sieboldii Miq. (chinese artichoke), which has been extensively used in oriental traditional medicine to treat of ischemic stroke; however, the role of Stachys sieboldii Miq. (SSM) in cerebral ischemia/reperfusion (I/R) injury is not yet fully understood. In the current study, the neuroblastoma cell line (SH-SY5Y) were subjected to oxygen-glucose deprivation/reperfusion (OGD/R) to simulate I/R injury in vitro model. The results showed that SSM improved OGD/R-induced inhibitory effect on cell viability of SH-SY5Y Cells. SSM displayed anti-oxidative activity as proved by the decreased levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and increased activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in OGD/R-induced SH-SY5Y Cells. In addition, cell apoptosis was markedly decreased after SSM treatment in OGD/R-induced SH-SY5Y Cells. The up-regulation of Bcl-2 and down-regulation of Bax, thus reducing the Bax/Bcl-2 ratio that in turn protected the activation of caspase-9 and -3, and inhibition of poly (ADP-ribose) polymerase cleavage, which was associated with the blocking of cytochrome c release to the cytoplasm. Collectively, SSM protected human neuroblastoma SH-SY5Y cells from OGD/R-induced injury via preventing mitochondrial-dependent pathway through scavenging excessive ROS, suggesting that SSM might be a potential agent for the ischemic stroke therapy.

• Food Science and Biotechnology
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• 제17권2호
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• pp.402-407
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• 2008

The synergistic antimicrobial effect of Achyranthes japonica Nakai (AJN) and Bifidobacterium extracellular factors against Clostridium difficile were measured using a turbidity method. Each broth supernatant of Bifidobacterium infantis ($68.8{\pm}0.02%$) and Bifidobacterium adolescentis ($33.2{\pm}0.2%$) obtained by adding ethyl acetate soluble fractionate from A. japonica Nakai ethanolic extracts (AJNEA, 100 ppm, no inhibition) showed high synergistic antimicrobial activity against C. difficile. In addition, the antimicrobial activity in a laboratory medium and yogurt products against C. difficile were evaluated. In yogurt prepared with a starter 5 (Lactobacillus acidophilus: Streptococcus thermophilus: B. adolescentis =1 : 1 : 1) and a starter 4 (L. acidophilus: S. thermophilus: B. infantis=1 : 1 : 1) and 0.5% AJNEA powder, high antimicrobial effects were recorded that measured 79.0 and 65.2%, respectively. The results indicated the potential of AJN extract for use as an antimicrobial agent. In addition, the efficiency of the antimicrobial activity of the extracts was further improved in combination with lactic acid bacteria, which suggests that they have the potential to be used as a highly effective antibiotic-tolerant microorganism prevention system. Such a strategy can be used for alternative drugs or functional food additives for treatment of antibiotic-associated diarrhea.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권4호
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• pp.269-273
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• 2001

This study presents a new formulation method for improving DNA transfection effi-ciency using a fusogenic peptide and polyethylene glycol-grafted polyethylenimine. Succinimidyls succinate polyethylene glycol (PEG-SSA) was conjugated with polyethylenimine(PEL). PEL is well known for a good endosomal escaping and DNA condensign agent. The positively charged syn-thetic fusogenic peptide, KALA was coated on the negatively charged PEG-g-PEI/DNA and PEI/DNA complexes. The KALA/PEI/ DNA complexes exhibited aggregation behavior at higher KALA coating amount with an effective diameter of around 1,000 nm. However, the LALA/PEG-g-PEI/DNA complexes were 100-300 nm in size with a surface zeta-potential (ζ)value of about +20mV. The conjugated PEG molecules suppressed any KALA-mediated inter-particle aggregation, and thereby improved the transfection efficiency, Consequently, the transfection efficiency of the KALA/PEG-g-PEI/DNA complexes was obtained by utilizing both the fusogenic activity of KALA and the steric repulsion effect of PEC.

• KSBB Journal
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• 제32권2호
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• pp.90-95
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• 2017

Mammalian cell cultures have been used extensively to produce proteins for therapeutic agent because of their ability to perform post-translational modification including glycosylation. To produce recombinant protein, many factors and parameter are considered such as media composition, host cell type, and culture process. In this study, recombinant human erythropoietin (rhEPO) producing cell line was established by using glutamine synthetase system. To reduce serum concentration in media, we compared direct adaptation with step adaptation. Cell growth was faster in step adaptation. In low-level serum media, there were insufficient glucose for cell growth. Thus, we added glucose in low-level serum media from 2 g/L to 4.5 g/L. Titer of rhEPO was higher than other conditions at 4.5 g/L of glucose. Additionally, N-methyl-D-aspartate (NMDA), 13-cis-retinal, and pluronic F-68 (PF-68) were added to enhance productivity in CHO cell cultures. In conclusion, we applied CHO cell producing rhEPO to low-level of serum in media using step-adaptation. Also, we confirmed positive effect of NMDA, 13-cis-retinal, and PF-68.

• Macromolecular Research
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• 제17권7호
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• pp.476-482
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• 2009

The crystallization behavior of poly(vinyl alcohol) (PVA) in the presence and absence of polypyrrole nanoparticles (PPy NPs) was investigated in terms of the heterogeneous nucleation effect of PPy NPs using FTIR, X-ray diffraction, differential scanning calorimeter and polarized optical microscope analysis. PPy NPs were prepared by dispersion polymerization method stabilized by PVA in aqueous solution. A polymer nanocomposite with uniform dispersity could be readily obtained due to the enhanced compatibility between the filler and matrix. Compared with the PPy NP-absent PVA, the PPy NP/PVA nanocomposite exhibited an enhanced degree of crystallinity. The degree of crystallinity increased up to 17% at the PPy NP concentration of 1 wt%, compared to the pristine PVA. The PPy NP acted as an effective nucleating agent during the crystallization process, thereby enhancing the degree and rate of crystallization. The kinetics study of the crystallization also revealed the decreased value of the Avrami coefficient in the case of the PPy NP/PVA nanocomposite.

• Korean Chemical Engineering Research
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• 제53권3호
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• pp.382-390
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• 2015

Poly(methyl methacrylate) (PMMA) supports and amine additives were investigated to adsorb $CO_2$. PMMA supports were fabricated by using different ratio of pore forming agents (porogen) to control the BET specific surface area, pore volume and distribution. Toluene and xylene are used for porogens. Supported amine sorbents were prepared by wet impregnation of tetraethylenepentamine (TEPA) on PMMA supports. So we could identify the effect of the pore structure of supports and the quantity of impregnated TEPA on the adsorption capacity. The increased amount of toluene as pore foaming agent resulted in the decreased average pore diameter and the increased BET surface area. Polymer supports with huge different pore distribution could be fabricated by controlling the ratio of porogen. After impregnation, the support with micropore structure is supposed the pore blocking and filling effect so that it has low $CO_2$ capacity and kinetics due to the difficulty of diffusing. Macropore structure indicates fast adsorption capacity and low influence of amine loading. In case of support with mesopore, it has high performance of adsorption capacity and kinetics. So high surface area and meso-/macro- pore structure is suitable for $CO_2$ capture.