• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.1
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• pp.31-37
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• 2015

Chelating agents 1,4,7-triazacyclononanetriacetic acid (NOTA), 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and 30-amino-3,14,25-trihydroxy-3,9,14,20,25-penta-azatriacontane-2,10,13,21,24-pentaone (desferrioxamine, DFO) were labeled with $^{68}Ga$ and tested in vitro properties to check the feasibility of using DFO as a bifunctional chelating agent or renal imaging agent. The chelating agents of concentration $2{\mu}M$ were labeled with $^{68}Ga$ in 0.1 M HCl at pH 1.7-10.3 at room temperature and $80^{\circ}C$ and the optimal pH for labeling each chelating agent was found. And then, the chelating agents were labeled with $^{68}Ga$ in various concentration of chelating agents at optimal pH. The labeled chelating agents were subject to stability test in human serum and to binding studies to human red blood cell (RBC) and plasma protein. The optimal pH's of NOTA, DOTA and DFO for $^{68}Ga$-labeling were 4.4, 3.6 and 5.6, respectively. DFO ($10{\mu}M$) showed high labeling efficiency (>97%) at pH 5.6. All the labeled chelating agents showed high stability in human serum. $^{68}Ga$-DFO showed low RBC binding but significant amount was bound to plasma protein. The results demonstrated that $^{68}Ga$-DFO can be used as a bifunctional chelating agent but not as a renal imaging agent.

• Natural Product Sciences
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• v.22 no.2
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• pp.111-116
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• 2016

Phytochemical investigation of the stems of Pueraria lobata (Wild) Ohwi (Leguminosae), led to the isolation of eighteen known compounds: ${\beta}$-amyrone (1), (+)-pinoresinol (2), (+)-syringaresinol (3) $(+)-syringaresinol-O-{\beta}-{\small{D}}-glucoside$ (4), (+)-lariciresinol (5), (-)-tuberosin (6), naringenin (7), liquiritigenin (8), isoliquiritigenin (9) genistein (10), daidzein (11) daidzin (12) daidzein 4',7-diglucoside (13) 2,4,4'-trihydroxy deoxybenzoin (14), S-(+)-1-hydroxy-3-(4-hydroxyphenyl)-1-(4-hydroxy-2-methoxy-phenyl)propan-2-one (15), methyl $2-O-{\beta}-{\small{D}}-glucopyranosylbenzoate$ (16), pyromeconic acid $3-O-{\beta}-{\small{D}}-glucopyranoside$ 6'- (O-4''-hydroxy-3-methoxybenzoate) (17), and allantion (18). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of those data with previously published results. The effects of isolated compounds on mushroom tyrosinase enzymatic activity were screened. The results indicated that, chloroform extract of P. lobata stems turned out to be having tyrosinase inhibitory effect, and only compounds 5, 8, 9, and 11 showed enzyme inhibitory activity, with $IC_{50}$ values of $21.49{\pm}4.44$, $25.24{\pm}6.79$, $4.85{\pm}2.29$, and $17.50{\pm}1.29{\mu}M$, respectively, in comparison with these of positive control, kojic acid ($IC_{50}\;12.28{\pm}2.72{\mu}M$). The results suggest that P. lobata stems extract as well as its chemical components may represent as potential candidates for tyrosinase inhibitors.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.347-352
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• 2014

The roots of Pueraria mirifica were extracted with 70% aqueous ethyl alcohol and partitioned into ethyl acetate (EtOAc), n-butyl alcohol (BuOH), and $H_2O$ fractions, successively. From the EtOAc fraction, four norsesquiterpenes were isolated through the repeated silica gel, octadecyl silica gel and Sephadex LH-20 column chromatographies. On the basis of physicochemical and spectroscopic data including nuclear magnetic resonance (NMR), mass spectrometry, and infrared spectroscopy, the chemical structures were identified as megastigm-5-en-3,9-diol (1), linarionoside B (2), 3,5,6,9-tetrahydroxymegastigm-7-ene (3) and 3,4,9-trihydroxymegastigma-5,7-diene (4). Especially, the configuration of the anomer hydroxyl group was determined as a from the coupling constants of the anomer proton (J =8.0 Hz) in the $^1H$-NMR spectrum. These compounds were isolated for the first time from the roots of P. mirifica in this study.

• Journal of Applied Biological Chemistry
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• v.48 no.4
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• pp.193-197
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• 2005

Isoflavones 4'-O-methylalpinumisoflavone (1) and 5, 7, 4'-trihydroxy-6,8-diprenylisoflavone (2) were isolated from stem bark of Cudrania tricuspidata (Carr.) Bureau. These compounds were the first reported from this plant. Antioxidant activities 1 and 2 were evaluated by measuring their ability to scavenge DPPH and ABTS radicals. Diprenylisoflavone 2 showed strong scavenging activity against ABTS ($IC_{50}\;=\;16.3\;{\mu}M$), three-fold higher compared to genistein, which do not possess prenylated group which indicates strong scavenging activity against ABTS radical of isoflavone 2 was due to prenyl group.

• Journal of Microbiology and Biotechnology
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• v.33 no.7
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• pp.949-954
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• 2023

Type III polyketide synthase (PKS) found in bacteria is known as 1,3,6,8-tetrahydroxynaphthalene synthase (THNS). Microbial type III PKSs synthesize various compounds that possess crucial biological functions and significant pharmaceutical activities. Based on our sequence analysis, we have identified a putative type III polyketide synthase from Nocardia sp. CS682 was named as ThnA. The role of ThnA, in Nocardia sp. CS682 during the biosynthesis of 1,3,6,8 tetrahydroxynaphthalene(THN), which is the key intermediate of 1-(α-L-(2-O-methyl)-6-deoxymannopyranosyloxy)-3,6,8-trimethoxynaphthalene (IBR-3) was characterized. ThnA utilized five molecules of malonyl-CoA as a starter substrate to generate the polyketide 1,3,6,8-tetrahydroxynaphthalene, which could spontaneously be oxidized to the red flaviolin compound 2,5,7-trihydroxy-1,4-naphthoquinone. The amino acid sequence alignment of ThnA revealed similarities with a previously identified type III PKS and identified Cys¹³⁸, Phe¹⁸⁸, His²⁷⁰, and Asn³⁰³ as four highly conserved active site amino acid residues, as found in other known polyketide synthases. In this study, we report the heterologous expression of the type III polyketide synthase thnA in S. lividans TK24 and the identification of THN production in a mutant strain. We also compared the transcription level of thnA in S. lividans TK24 and S. lividans pIBR25-thnA and found that thnA was only transcribed in the mutant.

• Biomolecules & Therapeutics
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• v.24 no.6
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• pp.616-622
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• 2016

Baicalein (5,6,7-trihydroxy-2-phenyl-chromen-4-one) is a flavone, a type of flavonoid, originally isolated from the roots of Scutellaria baicalensis. This study evaluated the protective effects of baicalein against oxidative damage-mediated apoptosis induced by ultraviolet B (UVB) radiation in a human keratinocyte cell line (HaCaT). Baicalein absorbed light within the wavelength range of UVB. In addition, baicalein decreased the level of intracellular reactive oxygen species (ROS) in response to UVB radiation. Baicalein protected cells against UVB radiation-induced DNA breaks, 8-isoprostane generation and protein modification in HaCaT cells. Furthermore, baicalein suppressed the apoptotic cell death by UVB radiation. These findings suggest that baicalein protected HaCaT cells against UVB radiation-induced cell damage and apoptosis by absorbing UVB radiation and scavenging ROS.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.1
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• pp.70-78
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• 2010

The purpose of this study is to investigate the appropriate metabolite as biomarker for the biomonitoring of 1,3-butadiene(BD) inhalation exposure. We measured the hemoglobin adducts which were extracted from the blood of the ICR mice inhalation exposure with 100ppm and 500ppm 1,3-butadiene for 2 weeks(5 hr/day ${\times}$ 5 days/week). Hemoglobin adducts were the (N-2-hydroxy-3 -butenyl) valine (HB Val) and (N-2,3,4-trihydroxy-butyl)valine (THB Val). Body weights of the exposure groups were significantly lower from 11 exposure post-day in 100ppm BD inhalation mice and from 7 exposure post-day in 500ppm BD inhalation mice than in control. The levels of HB Val are 0.8~1.7pmol/mg globin for 100ppm BD inhalation exposure, and 2.1~4.4 pmol/mg globin for 500ppm BD inhalation exposure. The levels of THB Val are 15.0~22.0 pmol/mg globin in 100ppm BD inhalation exposure, and 34.8~45.7 pmol/mg globin for 500ppm BD inhalation exposure. So the levels of THB Val and HB Val are proportional relationship with BD exposure level. THB Val is 12.9~18.8 times higher level that HB Val in 100ppm BD exposure group and 10.4~16.6 times higher level than HB Val in 500ppm BD exposure group. We concluded that THB Val is an appropriate metabolite as biomarker for the biomonitoring for BD inhalation exposure.

• Biomolecules & Therapeutics
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• v.15 no.2
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• pp.95-101
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• 2007

Resveratrol (3,5,4’-trihydroxy-trans-stilbene), a naturally occurring phytoallexin abundant in grapes and several plants, has been shown to be active in inhibiting proliferation and inducing apoptosis in several human cancer cell lines. On the line of the biological activity of resveratrol, a variety of resveratrol analogs were synthesized and evaluated for their growth inhibitory effects against several human cancer cell lines. In the present study, we found that one of the resveratrol analogs, 3,4,5-trimethoxy-4’-bromo-cis-stilbene, markedly suppressed human colon cancer cell proliferation (EC$_{50}$ = 0.01 ${\mu}$g/ml), and the inhibitory activity was superior to its corresponding trans-isomer (EC$_{50}$ = 1.6 ${\mu}$g/ml) and resveratrol (EC$_{50}$ = 18.7 ${\mu}$g/ml). Prompted by the strong growth inhibitory activity in cultured human colon cancer cells (Col2), we investigated its mechanism of action. 3,4,5-Trimethoxy-4’-bromo-cis-stilbene induced arrest of cell cycle progression at G2/M phase and increased at sub-G1 phase DNA contents of the cell cycle in a time- and dose-dependent manner. Colony formation was also inhibited in a dose-dependent manner, indicating the inhibitory activity of the compound on cell proliferation. Moreover, the morphological changes and condensation of the cellular DNA by the treatment of the compound were well correlated with the induction of apoptosis. These data suggest the potential of 3,4,5-trimethoxy-4’-bromo-cis-stilbene might serve as a cancer chemotherapeutic or chemopreventive agent by virtue of arresting the cell cycle and inducing apoptosis for the human colon cancer cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.482-494
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• 1994

Most of carotenoprotein complexes have been extracted by using buffered solutions. However, in this study carotenoprotein from the muscle of Blue mussel(Mytilus edulis) was extracted by a detergent such as Triton X-100. It was purified and characterized by $20\%$ (w/v) $(NH_4)_2SO_4$, DEAE-cellulose ion exchange and Sephacryl S-300 gel filtration. The carotenoprotein(${\lambda}_{max}=462nm$) had an approximate M. W. of 372KDa(gel filtration). SDS-PAGE analysis of the carotenoprotein indicated the presence of four polypeptides of 60KDa($23.70\%$), 46.9KDa($9.14\%$), 26KDa($49.14\%$) and 13KDa($18.02\%$). Carotenoprotein denaturated by treatment with SDS to a final concentration of $0.2\%$ (w/v) caused a hypsochromic shift of ${\lambda}_{max}$ from 462nm to 456nm. The carotenoprotein contained lipids as structure units. The amino acid composition of the carotenoprotein contained large essential amino acid amounts of $62.8\%$, and the content of threonine($35.9\%$) was higher than other amino acids, but histidine, methionine and proline were not present. In the carotenoprotein, the major fatty acids were $C_{16:4},\;C_{16:0},\;C_{20:5}\;and\;C_{22:6}$. The percentages of polyunsaturated fatty acids($62.4\%$) were higher compared to other fatty acids(saturated fatty acids $19.6\%$, monounsaturated fatty acids $18.0\%$). Carotenoid was extracted from the carotenoprotein by acetone and it was separated into five different components by preparative TLC(benzene:petroleum ether:acetone=69:17:14). The major components of carotenoid were mytiloxanthin($74.79\%$) and 3,4,3'- trihydroxy-7',8'-didehydro-${\beta}$-carotene($18.26\%$), and they were at least presented as prosthetic groups of carotenoprotein.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.535-548
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• 1994

Community structures and fish densit were investigated on three different types of artificial reefs, dice, turtle artificial reef and tubes, constructed in the Korean waters. Variations of fish fauna according to type of artificial reef and the proper artificial reef in each area for optimizing harvest were discussed. Fish were captured by trammel gill net during May, June, September and November, 1988 and both identified and counted. Fourty-five fish species were found in the artificial reefs. Of these, Sebastes spp., Hexagrammos otakii, Pleuronectidae, Navodon modestus and Stephanolepis cirrhifer showed high occurrence-frequency. The dominant species groups were coastal settlement, demersal or rock fishes such as Pleuronectidae, Rajiformes, Stephanolepis cirrhifer, Navodon modestus, Hexagrammos otakii and Sebastes spp. in all of the Artificial reefs except the oceanic area of southern waters. Scomber japonicus was predominant in the oceanic area of southern waters. Composition of demersal, rock and pelagic fishes were different depending on the types of artificial reef. Dice artificial reefs were occupied by rock fish, on the other hand turtle artificial reefs were dominated by dermersal fish. Fish density was high at the dice artificial reef in all survey areas except the middle area of Eastern waters, with high fish density evident in the Tube artificial reef. Fish community structures were remarkably different between Dice and Turtle artificial reefs. The Tube artificial reef showed intermediate characteristics between the above two types of artificial reefs. The coastal areas of Southern waters and the middle and southern areas of Western waters revealed similar fish fauna. Results from the oceanic areas of Southern waters were well associated with the middle and southern areas of Eastern waters.