• 한국약용작물학회:학술대회논문집
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• 2008.05a
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• pp.61-62
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• 2008

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.281-282
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• 2012

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.256.1-256.1
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• 2003

As a part of our ongoing research to discover novel monamine oxidase (MAO) inhibitors of plant origin, we found that a MeOH extract from the whole plant of Cayratia japonica (Vitaceae) strongly inhibited the MAO activity in mouse brain. The EtOAc-soluble fraction was. therefore, subjected to the bioactivity-guided fractionations to isolate the active compounds. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.247.1-247.1
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• 2003

PPAR-$\gamma$(Peroxisome Proliferator-Activated Receptor $\gamma$) 리간드들은 논문 조사를 통해 이루어졌다. PPAR-$\gamma$의 45개 알려진 화합물들을 찾았고, 12 생물활성 화합물을 선택했다. 리간드(rosiglitazone)과 단백질의 결합된 구조는 (1fm6)는 PDB로부터 획득했고, 단백질 coordinate를 가져와 PPAR의 활성 영역 잔기들은 확인했다. (2TYR, 1SER, 1HIS). CoMFA와 Flexi Dock을 통해 단백질과 리간드 사이의 상호작용과 결합에너지에 대한 상호 관계를 밝혔다.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.190.3-190.3
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• 2003

Three new butenolides (1-3), and a new cyclopentenone derivative (4) were isolated from a marine sponge Homaxinella sp. by bioactivity guided fractionation. The gross structures were established on the basis of NMR and MS analyses. The stereochemistry of the butenolides and cyclopentenone derivative was defined on the basis of optical rotation and CD spectroscopy. The compounds were tested against a panel of five human solid tumor cell lines and displayed marginal to significant cytotoxicity.

• Natural Product Sciences
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• v.5 no.2
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• pp.104-106
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• 1999

The chloroform fraction of the aqueous extract of the fresh leaves of Vitex negundo by bioactivity guided isolation yielded a pure compound, rotundial (1) which has shown potent mosquito repellent activity. Using spectral data (UV, IR, $^1H\;&\;^{13}C$ NMR and MS) its structure has been elucidated.

• Journal of Periodontal and Implant Science
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• v.42 no.3
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• pp.95-104
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• 2012

Purpose: The purpose of this study was to determine whether increasing the Ti6Al4V surface oxide negative charge through heat ($600^{\circ}C$) or radiofrequency plasma glow discharge (RFGD) pretreatment, with or without a subsequent coating with fibronectin, stimulated osteoblast gene marker expression in the MC3T3 osteoprogenitor cell line. Methods: Quantitative real-time polymerase chain reaction was used to measure changes over time in the mRNA levels for osteoblast gene markers, including alkaline phosphatase, bone sialoprotein, collagen type I (${\alpha}1$), osteocalcin, osteopontin and parathyroid hormone-related peptide (PTH-rP), and the osteoblast precursor genes Runx2 and osterix. Results: Osteoprogenitors began to differentiate earlier on disks that were pretreated with heat or RFGD. The pretreatments increased gene marker expression in the absence of a fibronectin coating. However, pretreatments increased osteoblast gene expression for fibronectin-coated disks more than uncoated disks, suggesting a surface oxide-mediated specific enhancement of fibronectin's bioactivity. Heat pretreatment had greater effects on the mRNA expression of genes for PTH-rP, alkaline phosphatase and osteocalcin while RFGD pretreatment had greater effects on osteopontin and bone sialoprotein gene expression. Conclusions: The results suggest that heat and RFGD pretreatments of the Ti6Al4V surface oxide stimulated osteoblast differentiation through an enhancement of (a) coated fibronectin's bioactivity and (b) the bioactivities of other serum or matrix proteins. The quantitative differences in the effects of the two pretreatments on osteoblast gene marker expression may have arisen from the unique physico-chemical characteristics of each resultant oxide surface. Therefore, engineering the Ti6Al4V surface oxide to become more negatively charged can be used to accelerate osteoblast differentiation through fibronectin-dependent and independent mechanisms.

• Korean Journal of Plant Resources
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• v.32 no.6
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• pp.723-729
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• 2019

Fagopyrum esculentum (Buckwheat) is a globally used alternative crop that contains several useful substances with various effects; however, many of these substances (rutin, quercetin, etc.) are water insoluble. To extract these substances, alcohols is required, which is inconvenient because these solvents cause diverse problems. Many studies are underway to achieve effective extraction of these substances with water. Among of these studies, microwave assisted water extraction (MAE) has been performed extensively. In this study, we performed the extraction in various solvents and/or microwave from Fagopyrum esculentum. The analysis of the content of useful substances and the bioactivity were performed and shown to increase in MAE. Liquid chromatography-mass was performed in order to identify of the useful water-insoluble substances. Catechin, quercetin, and rutin, which are all insoluble in water, were hardly extracted with water even on heating (4.4 ppb, 3.9 ppb and 60.3 ppb, respectively). However, MAE was found to extract much more of these substances than water (1204 ppb, 110.8 ppb and 2946 ppb, respectively). Although less efficient than alcohols, MAE showed much higher efficiency than simple water extraction. These results indicate that water extraction using microwave technology is effective in cases where it is difficult to extract useful substances using water.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.85-88
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• 2001

We scaled up a covalent immobilization system of urokinase to the activated Sepharose and used it repeatedly to cleave a fusion protein consisting of human growth hormone and GST fragment. After scale up from 6 ml to 250 ml, the column system still demonstrated basically the same performance in terms of urokinase immobilization and fusion protein cleavage. When the column was washed with 6M guanidine HCl after the cleavage reaction. the immobilized urokinase showed no activity probably because it was fully unfolded. However. as the denaturant was gradually removed from the column the immobilized urokinase fully regained its bioactivity. which indicated it was properly refolded into its native conformation as covalently attached to the solid matrix. After 20 cycles of this 'solid-phase unfolding/refolding', the immobilized urokinase maintained approx. 80% of the initial bioactivity. This method provides an efficient protocol to apply the solid-phase refolding technique to improve the longevity of immobilized enzyme columns.

• KSBB Journal
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• v.16 no.5
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• pp.500-504
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• 2001

We scaled up a covalent immobilization system of urokinase to the activated Sepharose and used it repeatedly to cleava a fusion protein consisting of human growth hormone and GST fragment. After scale up from 6 ml to 250 ml. the column system still demonstrated basically the same performance in terms of urokinase immobilization and fusion protein cleavage. When the column was washed with 6 M guanidine HCI after the cleavage reaction, the immobilized urokinase showed no activity probably becasue it was fully unfoled. However, as the denaturant was gradually removed from the column the immobilized urokinase fully regained its bioactivity, which indicated it was properly refolded into is natie conformation as covalently attached to the solid matrix. After 20 cycles of this solid-phase unfolding/refolding. the immobilized urokinase maintained approx. 80% of the initial bioactivity. This method provides and efficient protocol to apply the solid-phase refolding technique to improve the longevity of immobilized enzyme columns.