• Natural Product Sciences
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• v.21 no.4
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• pp.227-230
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• 2015

Chemical investigation of the fermentation broth of a Soft Coral-Derived fungus Pestalotiopsis sp., led to the isolation of a new phthalide derivative, pestalotiolide A (1), three known analogues (2, 3 and 4), along with 5'-O-acetyl uridine (5) first isolated as a natural product. The structure of the new compound (1) was established by comprehensive spectroscopic analysis and chemical methods. Compounds 1 - 4 possessed varying degrees of antiviral activities, which was reported for the first time. Compared to the positive control ribavirin ($IC_{50}=418.0{\mu}M$), pestalotiolide A (1) exhibited significant anti-EV71 activity in vitro, with an $IC_{50}$ value of $27.7{\mu}M$. Furthermore, the preliminary structure-activity relationship of antiviral activities was also discussed.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.396-408
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• 2017

This study aims to analyze pre-service elementary teachers' oceanographic literacy, understanding of ocean environmental problems and opinions on teaching strategies for ocean topics. As survey participants, this study selected 126 pre-service elementary teachers. Firstly, as a result of testing their oceanographic literacy, this study found out that out of all the basic principles, 'Oceans Largely Unexplored' was highest in the mean score, followed by 'Human Connections', 'Ocean & Its Life Shape Earth', 'Habitability', 'Biodiversity', 'Weather & Climate' and 'Size of Ocean'. Besides, regarding environmental problems affecting all the aspects of ocean, they mentioned oil spills caused by vessel accidents, so called 'Oil Pollution', as the most serious marine environmental problem. Regarding environmental problems affecting coral reefs, they considered over-fishing as the most serious problem. Secondly, as a result of analyzing their opinions on effective teaching strategies for ocean-related topics in elementary science textbooks, this study found out that regarding topics about understanding the undersea topography in the chapter of the earth and moon, they proposed 'Making an Undersea Topographic Model with Sand' most as an effective teaching strategy. As an effective teaching strategy for the chapter of animals' lives, they proposed 'Classifying Animals with Marine Animal Cards' most. As an effective teaching strategy for the chapter of ground surface changes, they proposed 'Making and Simulating Seashore Topography' most.

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1042-1046
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• 2005

Two known modified dipeptides, trichodermamide A (1) and aspergillazine A (2), were isolated from an ethyl acetate extract of the metabolite of a marine-derived fungus Spicaria elegans, and were found to have a weak cytotoxic effect on three cancer cell lines P388, A-549, and HL-60 agreed. To our knowledge, this is the first report on the isolation of compounds 1 and 2 from the fungus Spicaria elegans and their cytotoxic effect.

• Archives of Pharmacal Research
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• v.28 no.12
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• pp.1341-1344
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• 2005

Bioassay-guided fractionation of $CHCl_{3}$ extract from the fermentation broth of a sponge Mycale plumose-derived actinomycete Saccharopolyspora sp. nov., led to the isolation of two known prodigiosin analogs - metacycloprodigiosin (1) and undecylprodigiosin (2). These compounds exhibited significant cytotoxic activities against five cancer cell lines: P388, HL60, A-549, BEL­7402, and SPCA4. This is the first report on the significant cytotoxicity of metacycloprodigiosin (1) against human cancer cell lines.

• Journal of the Korean earth science society
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• v.40 no.4
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• pp.392-405
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• 2019

Biogeochemical processes play an important role in ocean environments and can affect the entire Earth's climate system. Using an ocean-biogeochemistry model (NEMO-TOPAZ), we investigated the effects of changes in albedo and wind stress caused by phytoplankton in the equatorial Pacific. The simulated ocean temperature showed a slight decrease when the solar reflectance of the regions where phytoplankton were present increased. Phytoplankton also decreased the El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) amplitude by decreasing the influence of trade winds due to their biological enhancement of upper-ocean turbulent viscosity. Consequently, the cold sea surface temperature bias in the equatorial Pacific and overestimation of the ENSO amplitude were slightly reduced in our model simulations. Further sensitivity tests suggested the necessity of improving the phytoplankton-related equation and optimal coefficients. Our results highlight the effects of altered albedo and wind stress due to phytoplankton on the climate system.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.22-22
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• 2017

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.30-30
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• 2017

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.1
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• pp.1-17
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• 2005

The purpose of this study is to prepare the way for the prevention and improvement of the ocean environment pollution and destruction by researching and analyzing the degree of interests in the ocean environment which the students of seaside vocational high schools have. The concerns of this study are as follows: 1. The vocational high school students in the seaside cities of Busan and Pohang have recognized that the ocean is the object of the highest potential of development and that through the degree of their recognition that they should better preserve the ocean environment prior to a high degree of local seaside development. 2. Although they have recognized that the ocean environment has a great influence on the life of people, their interests in the environment is low. Also, it is shown that they get their knowledge and information through TV. 3. They've understood that the main factor of ocean contamination concerns the home and the causes of ocean contamination are sewage and waste material from daily life. Moreover, their answers reveal that they believe that they should participate in a sanitization activity for the ocean environment voluntarily and put trash into nearby trash cans as opposed to inconsiderately throwing away trash on the beach. 4. Their answers also show that they recognize the elements that can best preserve the ocean environment start at home and with government, and school services through experience activities are the most effective for the education of the ocean environment.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3495-3501
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• 2014

A novel crystal, the mono-protonated metformin acetate (1), was obtained and characterized by elemental analysis, IR spectroscopy and X-ray crystallography. It was found that one of the imino group in the metformin cation was protonated along with the proton transfer from the secondary amino group to the other imino group. Its crystal structure was then compared with the previously reported diprotonated metformin oxalate (2). The difference between them is that the mono-protonated metformin cations can be linked by hydrogen bonding to form dimers while the diprotonated metformin cations cannot. Both of them are stabilized by intermolecular hydrogen bonds to assemble a 3-D supermolecular structure. The four potential tautomer of the mono-protonated metformin cation (tautomers 1a, 1b, 1c and 1d) were optimized and their single point energies were calculated by Density Functional Theory (DFT) B3LYP method based on the Polarized Continuum Model (PCM) in water, which shows that the most likely existed tautomer in human cells is the same in the crystal structure. Based on the optimized structure, their Wiberg bond orders, Natural Population Analysis (NPA) atomic charges, molecular electrostatic potential (MEP) maps were calculated to analyze their electronic structures, which were then compared with the corresponding values of the diprotonated metformin cation (cation 2) and the neutral metformin (compound 3). Finally, the possible tautomeric mechanism of the mono-protonated metformin cation was discussed based on the observed phenomena.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.931-937
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• 2018

Glycosyltransferases (GTs) from microbes are an emerging and rich source for efficient glycol-transformation of natural/unnatural compounds. Here, we probed the catalytic capability and substrate promiscuity of BmmGT1 from marine-derived Bacillus methylotrophicus B-9987. The regioselectivity of BmmGT1 on macrolactin A (1) was explored by optimization of the reaction conditions, in which a series of O-glycosylated macrolactins (1a-1e) were generated, including two new di/tri-O-glucosyl analogs (1b and 1e). Furthermore, BmmGT1 was able to catalyze the glycosylation of the thiol (S-) or amine (N-) sites of phenolic compounds (2 and 3), leading to the generation of N- (2a) or S-glycosides (3a and 3b). The present study demonstrates that BmmGT1 could serve as a potential enzyme tool for O-, N-, or S-glycosyl structural diversification of compounds for drug discovery.