• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.83-83
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• 2013

To date, various nanobiotechnologicalapproaches for biosensors and drug development have been explosively studied. Despite of successful demonstrations, the new technologies hardly enjoyed routine applications in practical nanobiomedicine. Here, researchers trained at the interface of basic sciences and engineering are expected to play critical roles. In this tutorial, I will introduce recent studies which harness graphene derivatives for developing bioanalytical platforms to quantitatively analyze various enzyme activities and biomarkers. The systems rely on attractive interaction between graphene oxide and nucleic acids or phospholipids. Recently, one of the graphene-based bioassay system was applied to anti-viral drug screening and potent hit compounds were identified to treat hepatitis C. This study clearly shows that a new nanobio-technology can be routinely implemented in drug discovery, providing many advantages over conventional methods.

• 한국미생물·생명공학회지
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• 제22권4호
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• pp.382-388
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• 1994

In the course of screening for insecticidal metabolites from soil microorganisms, Actinomycetes isolate no.1166 was found to produce active metabolites against Musca domestca and Bombyx mori. Three active components from the metabolites were isolated by solvent extraction and chro- matographic techniques and examined their insecticidal activities on Bombyx mori (3rd larvae) by diet feeding bioassay methods. By UV and NMR data analyses, compound I and III were identified as bafilomycin A$_{2}$ and B$_{1}$, respectively and compound II was also estimated to belong to the bafilomycin family from its physico-chemical data and biological properties.

• Archives of Pharmacal Research
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• 제20권4호
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• pp.342-345
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• 1997

A cytotoxic constituent was isolated by bioassay-guided procedure from the roots of Sophora flavescens Aiton (Leguminosae). The constituent was identified as sophoraflavanone G (I) by means of chemical methods and in comparsion with spectral data of standard compound. The $ED_50$ values of constituent I were 0.78, 1.57, 2.14 and $8.59{\mu}g/ml$ against A549, HeLa, K562 and L1210 cell lines, respectively. Constituent I exhibited highly cytotoxic activities against A549, K562 and HeLa cells, but showed a mild activity $$(ED_50 value, 5{\mu}g/ml)$$ against L1210 cells. Among the tested cell lines, A549 cells were the most sensitive to constituent I.

• 한방안이비인후피부과학회지
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• 제17권1호
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• pp.126-130
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• 2004

Objectives; Bioassay-directed fractionation of the dried roots of Salvia miltiorrhiza led to the isolation of abietane tanshinones, crptotanshinone and dihydrotanshinone. Methods: Their structures were elucidated using 1H-and 13C-NMR, UV, IR and mass spectral analysis. Result and Conclusions : These compounds exhibited a moderate antimicrobial activities against Staphylococcus epidemidis, Staphylococcus aureus, Staphylococcus pyogene. Actinobacillus actinomycetemcomitans, Escherichia coil, Enterbacter cloacae, Pseudomonas aeruginosa, Citrobacter freundii, and Samonella typhimurium.

• Natural Product Sciences
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• 제15권2호
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• pp.90-95
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• 2009

Phytochemical investigation of the MeOH extract of the leaves of Nelumbo nucifera resulted in the isolation of five norsesquiterpenes, four flavonoids, two triterpenes and one alkaloid. Their chemical structures were characterized by spectroscopic methods to be (E)-3-hydroxymegastigm-7-en-9-one (1), (3S,5R,6S,7E)- megastigma-7-ene-3,5,6,9-tetrol (2), dendranthemoside B (3), icariside $B_2$ (4), sedumoside $F_1$ (5), luteolin (6), quercetin 3-0-${\beta}$-D-glucuronide (7), quercetin 3-0-${\beta}$-D-glucoside (8), isorhamnetin 3-0-rutinoside (9), alphitolic acid (10), maslinic acid (11), and N-methylasimilobine (12). Norsesquiterpenoids (1-5) and triterpenes (10-11) were isolated for the first time from this plant. Compounds 6 and 10-12 exhibited considerable cytotoxicity against four human cancer cell lines in vitro using a SRB bioassay.

• BMB Reports
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• 제31권1호
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• pp.101-105
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• 1998

Immunoassay of botulinum toxin (BTX) B type was investigated using two typed of biosensors: light addressable potentiometric sensor (LAPS) and surface plasmon resonance (SPR) sensor. Urease-tagged and immuno-filtration capture method have been used for LAPS. Tag-free and direct binding real-time detection method have been used for SPR sensor. The detection limit of sandwich assay format with LAPS was 10 ng/ml, which was the lowest among methods tested. SPR has the advantage of being more convenient because tag-free direct binding assay can be used and reaction time was reduced, regardless of low sensitivity. This result shows that sandwich assay format with LAPS can be used as an alternative method of BTX mouse bioassay which is known as the most sensitive method for the detection of BTX.

• Natural Product Sciences
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• 제20권2호
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• pp.71-75
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• 2014

Nine triterpenes were isolated from the petroleum ether and MeOH extract of Perilla frutescens var. acuta leaves. Their structures were determined to be arjunic acid (1), maslinic acid (2), oleanolic acid (3), euscaphic acid (4), tormentic acid (5), 3-O-trans-p-coumaroyltormentic acid (6), 28-formyloxy-$3{\beta}$-hydroxy-urs-12-ene (7), ursolic acid (8), and corosolic acid (9) by spectroscopic methods. The compounds 1, 2, 4, 6, and 7 were isolated for the first time from this plant and the Genus Labiatae. The isolated compounds (1-9) were tested for cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15) in vitro using a Sulforhodamin B bioassay.

• Natural Product Sciences
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• 제8권2호
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• pp.48-51
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• 2002

Antioxidative properties of fifteen anthraquinone derivatives, including eleven atural anthraquinones isolated from the roots of Morinda elliptica and four from synthetic origin were evaluated using thin layer chromatography (TLC), ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. Five of the compounds, nordamnacanthal, damnacanthal, 2-formyl-1-hydroxyanthraquinone, morindone and alizarin showed higher antioxidative activity than standard natural antioxidant, ${\alpha}-tocopherol$, on the FTC assay. Morindone and alizarin showed the strongest antioxidant activity. The results from the bioassay using TBA method correlated well with the results of the FTC method.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.174-174
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• 1998

Twelve different derivatives were synthesised from chitin/chitosan[1, 2, 3]. Their structures have been determined by different physical methods. The bioassay screening on antifungal and antibacterial activities of all these compounds showed that most of them had significant activity and they can inhibite the growth of some fungi and bacterias : E. coli, S. pyogenes, F. oxysporum, P. oryzae, that caused the spoilage of fresh fruits and foods. Furthermore, all of these compounds are non-toxic (LD$\_$50/>50g/kg) and can be applied for food preservation.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.91-91
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• 1993

The vast number of compounds which have been introduced into our environment in recent years is far beyond our capacity to assess for carcinogenicity using expensive, life-time carcinogenicity studies in rodents. Several in vitro short term assays which are very rapid and inexpensive have therefore been applied as mass screening methods. However, increasing evidence has indicated that mutagenicity results do not always correlate with long-term carcinogenicity. Therefore, the existence of discrepancies dictates the necessity of suitable in vivo rapid assay systems which could bridge the gap between mutagenicity and conventional long-term testing.