• Interdisciplinary Bio Central
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• v.5 no.2
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• pp.4.1-4.3
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• 2013

A history of discoveries of a gene and DNA was viewed with respect to people, time and places. It started with G. Mendel and J. Meisher, who discovered a gene in a plant species in 1866 and DNA in animals in 1869, respectively. With recognition that DNA was a chemical substance, A. Kossel identified the four chemical components of DNA without knowing their biological function around the turn of the 19th century. On the other hand F. Griffith found a peculiar activity in a bacterial species in 1928, but victimized by the war before understanding what it was. Those discoveries were made in Europe, but they were still fragmentary. Then, in USA, O. T. Avery, A. Hershey, M. Nirenberg and other scientists organized the European discoveries and elucidated their coordinated biological functions in 1950's and 1960'.

• Advances in Traditional Medicine
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• v.6 no.1
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• pp.53-57
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• 2006

The plant Indigofera aspalathoides is used by a large number of tribes in India for the treatment of various hepatic disorders and abscesses. The methanol extract of Indigofera aspalathoides (MEIA) was evaluated for its protective effects on gastric mucosal lesion in Wister albino rats against indomethacin, histamine and ethanol induced gastric mucosal damage. The response to MEIA was assessed using the ulcer index, thiobarbituric acid reactive substance (TBARS), and glutahione level. MEIA pretreatment showed protection against chemical induced gastric mucosal damage, a significant reduction in the ulcer index and TBARS activity and increase glutathione level as compared with that of standard drugs.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.26-32
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• 1998

The chemical composition of differentiating xylem of Populus deltoides M. were investigated and compared with those from sapwood. The cell wall polysaccharides were extracted sequentially from a differentiating xylem and sugar composition was analyzed with G.L.C, H.P.L.C and gel chromatograpy. The pectin substance and hemicellulose are rich in the cell wall of differentiating xylem. The $H_2O$ extract polysaccharides from differentiating xylem were composed with xylose-glucose residues which seem to be xyloglucan and a pectin. The arabinogalactan and the mannan were extracted with $Na_2CO_3$ solution and also the xylan was extracted with KOH solution. Sugar composition of each fractions in gel filteration of purified $H_2O$ polysaccharide suggests that the xyloglucan can be extracted with $H_2O$ from differentiating xylem.

• YAKHAK HOEJI
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• v.12 no.3_4
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• pp.72-75
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• 1968

It has been believed that "Kup kee" (Chloranthus japonica) is good for boils, or dermatopathia, and enteric fever by the Korean folks. However, there is no scientific report on its chemical ingredients and its antibacterial activities so far. The roots of Chloranthus japonica were dried and pulverized. The pulverized powder was then extracted with methanol. Then an extract was obtained by following Stas Otto's method. finally a crystal fraction was obtained through Column Chromatography. Recrystalization from methanol gave white needle crystals, m.p. $198^{\circ}C.$ Generally this compound has shown strong antibacterial effects on Gram negative bacteria. It exerts most powerful effect on Salmonella typhi. on the other hand it shows weak effect on Inaba cholera.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.93-99
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• 2002

In this paper, the effect of the mud of an inorganic substance dyed on cotton knitted fabrics have been studied. The structure and chemical composition of mud was analyzed. And the far-infrared emissivity and emission power, colorfastness, anti-bacterial properties cotton knitted fabrics dyed with mud were also evaluated. The structure and chemical composition of mud was almost identical structure and to be alike main components were SiO2, A1203 and Fe203. The cotton knitted fabrics dyed with mud have good components and anti-bacterial properties. when the dyed fabrics was after-treated with diphenyl ether, the anti-bacterial property were improved. Far-infrared emissivity and emission fewer cotton knitted fabrics dyed with mud have very good.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.36-46
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• 1962

The author assumes that pure liquid metal is composed of molecular oscillators whose energy states are classified into two subgroups, i.e., A and B states, each being accesible to either one of the two sorts of lattice sites. The partition function involves constants characteristic of substance, which are obtainable from the Debye characteristic temperature assigned to its solid state. Calculation has been made for the various thermodynamic properties such as the vapor pressure, the entropy, and the heat capacity of liquid metals of GroupⅠelements over the temperature range from the melting points to the boiling points. The theoretical values thus obtained are in good accordances with those observed, within experimental error, although a slight derivation is observed in the atomic heat capacity.

• Journal of Environmental Science International
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• v.11 no.2
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• pp.131-137
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• 2002

The chemical behavior and properties on the redox state of environmental pollutant has been investigated by electrochemical methods. We carried out to measure the variations in the redox reaction of differential pulse polarogram and cyclic voltammogram. The results observed the influences on redox potential and current of various factors with temperature and pH. These were established factors as the effect of the redox reaction. It can be clearly recognized that the electrode reaction are from qusi-reversible to irreversible processes. Also, it was mixing with reaction current controlled. The bits-phenol A in the waste water was made to compound with cobalt ion and it take away from the separation into compound. The $Co(BPA)_2$ compound was not found to be dissociation in waste water. However, this compound is avery unstable(K=1.02) and for a while, it was to be a dissociation. Therefore, we believed that it was likely to a toxic substance.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3726-3729
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• 2011

Biofilm formation is inevitable in a bioelectrochemical system in which microorganisms act as a sole biocatalyst. Cathodic biofilm (CBF) works as a double-edged sword in the performance of the air-cathode microbial fuel cells (MFCs). Proton and oxygen crossover through the CBF are limited by the robust structure of extracellular polymeric substances, composition of available constituents and environmental condition from which the biofilm is formed. The MFC performance in terms of power, current and coulombic efficiency is influenced by the nature and origin of CBF. Development of CBF from different ecological environment while keeping the same anode inoculums, contributes additional charge transfer resistance to the total internal resistance, with increase in coulombic efficiency at the expense of power reduction. This study demonstrates that MFC operation conditions need to be optimized on the choice of initial inoculum medium that leads to the biofilm formation on the air cathode.

• Journal of the Korean Chemical Society
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• v.60 no.4
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• pp.257-260
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• 2016

A new perfluorobutyl substituted cyclic type disodium alkanesulfonate is designed, synthesized and characterized as alternative substance to perfluorooctane sulfonic acid (PFOS, 1), a well-known surfactant. Cylic type sulfonate was accomplished from commercially available 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol in four steps. Bio-degradable perfluorobutyl moiety was introduced from fluorous diol, which is symmetrically substituted amphiphile via installation of an intermediate trifluoromethanesulfonyl ester and easily manipulated by double displacement of triflate using potassium malonate and further reduction followed by nucleophilic ring opening are key reactions to get target disodium alkanesulfonate. The efficiency and simplicity in the synthesis of this material offer a new strategy to design PFOS alternatives.

• Journal of the Korean Chemical Society
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• v.8 no.2
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• pp.82-84
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• 1964

It has been pointed out that various substances such as "toxoalbumin", glycoside, choline or readily hydrolysable choline derivatives, alkaloid, lysolecithine etc. are associated with the toxicity of the infected grain. But animal tests and analysis of paper chromatography by author's indicated that a basic substance present in the concentrated extracts from the grain may neither be acetylcholine, betaine, nor choline. This problem still have to be examine further.