• Analytical Science and Technology
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• v.37 no.4
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• pp.239-250
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• 2024

This study reports the synthesis of a bi-dentate Schiff base ligand (L), 7-(2-((2-formylbenzylidene) amino)-2-phenylacetamido)-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, prepared from phthalaldehyde and cephalexin antibiotic. The synthesized Schiff base ligand (L) and the secondary ligand alizarin (Az) are used to prepare the new complexes [M(Az)₂(L)] and [Cr(Az)₂(L)]Cl, where M = Mn(II), Co(II), Ni(II), Cu(II), and Zn(II). The mode of bonding of the Schiff base has been characterized by UV-Visible, FT-IR, Mass, ¹H-, and ¹³C-NMR spectroscopic techniques, and micro elemental analysis (CHNS). The complexes were characterized using UV-Vis, FT-IR, molar conductance, magnetic moment, and thermal analysis (TG/DTG). The molar conductance data revealed that the complexes are non-electrolytes except for [Cr(L)(Az)₂]Cl, which is an electrolytic type 1:1. The Schiff base and its complexes have been tested for their biological activity against two strains of bacteria and one fungus. When screened against gram-positive and gram-negative pathogens, the Az and L ligands and their complexes showed potential antimicrobial activity.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.407-412
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• 2014

Lactulose is well known for functional component in the food and pharmaceutical field and utilized in a wide variety of foods as a bifidus factor or functional ingredient for intestinal regulation. Lactulose synthesis can be classified into chemical and biological methods. In chemical methods, lactulose is synthesized by alkaline isomerization, but it has many disadvantages such as including product purification, lactulose degradation, side reactions and waste management. Therefore, the enzymatic synthesis methods were recently studied to solve these problems. ${\beta}$-galactosidase is a important enzyme in the dairy industry, because of the production of lactose-hydrolyzed products. Also, ${\beta}$-galactosidases can be utilized to synthesize lactulose from lactose by a trans-galactosylation reaction, using fructose as a galactosyl acceptor. However, the synthesis of lactulose from lactose is economically not suitable due to high levels of lactose price. This review summarizes the current state of lactulose production by chemical and biological processes.

• YAKHAK HOEJI
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• v.52 no.2
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• pp.131-136
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• 2008

Sesamol, one of constituents isolated from sesame seed (Sesamum indicum L.) has been known to have natural antioxidant property. Nicotinic acid and clofibric acid have been used for treatment of hyperlipidemia. Sesamol derivatives prepared by conjugation with nicotinic acid (SJ-301) and clofibric acid (SJ-302) were expected to have various biological activity caused by synergistic effect of sesamol. Thus, this study were carried out to investigate the synthesis of sesamol derivatives from seasamol and antihyperlipidemia drugs and their biological activities. As a result, SJ-301 showed a stronger antihyperlipidemia activity in vivo and inhibitory effect on $TNF-{\alpha}$ release in vitro compared to the original agents such as sesamol, nicotinic acid and clofibric acid.

• The Korean Journal of Nuclear Medicine
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• v.36 no.4
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• pp.209-223
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• 2002

By considering the biological properties of a tumor, it should be possible to realize better results in cancer therapy. PET imaging offers the opportunity to measure tumor growth non-invasively and repeatedly as an early assessment of response to cancer therapy. Measuring cellular growth instead of energy metabolism showed offer significant advantages in evaluating therapy. Thymidine and its derivative nucleoside compounds can be changed to mono, di- and tri- phosphate compounds by thymidine kinase and then be incorporated into DNA. Their bindings are increased in highly proliferating cells due to the high DNA synthesis rate. To evaluate cell proliferation, many kinds of thymidine and uridine derivatives have been labeled with positron emitter and radioactive iodine. Compared to radiopharmaceuticals which have radioisotope labeled base ring such as pyirmidine, the radiopharmacuticals which have radioisotope labeled sugar ring are more stable in vivo and have metabolic resistance. The biological properties such as DNA incorporation ratios are highly dependent on their chemical structures and metabolic processes. This overview describes synthesis of radiopharmaceuticals and their biological properties for imaging of tumor cell proliferation.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.556-556
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• 2005

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.254.2-255
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• 2000

No Abstract, See Full Text

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.59-61
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• 2003

Organic compounds play an important role in the area of pharmaceutical, agrochemical, and other materials, which possess useful biological activities. Generally, such biological activities are come from the interaction of the organic compounds with the receptors in biological system, such as enzymes. Such receptors are composed of the chiral building blocks such as amino acid or carbohydrate, which means the biological active sites of receptors are chiral. (omiited)

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.44-56
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• 1998

This study was performed to investigate the reaction characteristics of piggery wastewater for biological nutrient removal. The reaction characteristics were discussed the fraction of organics, the behavior of nitrogen, nitrification, denitrification, and the behavior of phosphorus. The fraction of readily biodegradable soluble COD was 11-12 percent. The ammonia nitrogen was removed via stripping, nitrification, autotrophic cell synthesis, and heterotrophic cell synthesis. The removal percents by each step were 12.1%, 68.9%, 15.0%, and 4.0%, respectively. Nitrification inhibition of piggery wastewater was found to occur at an influent volumetric loading rate over 0.2 NH$_{3}$-N kg/m$^{3}$/d. Denitrification rates were the highest in the raw wastewater and the lowest in the anaerobic effluent. The denitritation of piggery wastewater came out to be possible, and the rate of organic carbon consumption decreased about 10 percent. The phosphorus removed was released in the form of ortho-p in the aerobic fixed biofilm reactor, it was caused by autooxidation. The synthesis and release of phosphorus were related to the ORP and the boundary value for the phase change was about 170mV. In the synthesis phase, the phosphorus removal rate per COD removed was 0.023mgP$_{syn}$/mgCOD$_{rem}$. The phosphorus contents of the microorganism were 4.3-6.0% on a dry weight basis.

• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.274-279
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• 2007

This study focuses on the enhancement of maskless photolithography as well as the peptide synthesis application with single crystalline silicon micromirrors. A single crystalline silicon micromirror array has been designed and fabricated in order to improve its application to the peptide synthesis. A micromirror rotates about ${\pm}\;9^{\circ}$ at the pull-in voltage, which can range from 90.7 V to 115.1 V. A $210\;{\mu}m-by-210\;{\mu}m$ micromirror device with $270\;{\mu}m$ mirror pitch meets the requirements of an adequately precise separation for peptide synthesis. Synthetic 16 by 16 peptide array corresponds to the same number of micromirrors. The large size of peptide pattern and the separation facilitate biochip experiments using fluorescence assay. The peptide pattern has been synthesized on the GPTS-PEG200 surface with BSA-blocking and thereupon the background was acetylated to reject non-specific bindings. Hence, an averaged slope at the pattern edge has been distinguishably improved in comparison to patterning results from an aluminum micromirror.

• Advances in nano research
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• v.14 no.1
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• pp.103-115
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• 2023

Recent developments in the synthesis of nanomagnesia of controlled sizes and shapes that are suitable for various applications are reviewed. Two main methods, based on liquid-phase synthesis, i.e., chemical methods and bio-based methods, are used to synthesize nanomagnesia. Conventionally, nanomagnesia was synthesized by chemical methods such as coprecipitation, sol-gel, combustion method, and so on using different chemical agents and stabilizers which later on become responsible for several biological risks because of the toxicity of used chemicals. Bio-based protocols are growing as another environmental friend method for the synthesis of various nanostructures especially nanomagnesia using biomass, plant extracts, alga, and fungi as a source of precursor material. The ideal method should offer better control of textural properties of nanostructures and decrease the necessity for purification of the synthesized nanoproducts, which sequentially removes the use of large amounts of chemicals and organic solvents and manipulation of products that are unsafe to the environment. Finally, the broad applicability of nanomagnesia in diverse areas is presented. Employment of nanomagnesia reported in several laboratory and industrial fields are valued from the standpoint of the significance of these issues for technological requests, as described in the literature. Nanomagnesia has various applications such as antimicrobial performance, removing pollutants, batteries application, and catalysis.