• Food Science of Animal Resources
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• v.41 no.6
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• pp.997-1011
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• 2021

The processing characteristics of freeze-dried pork powder as raw meat for comminuted meat products were compared with those of freeze-thawed pork. The tertiary structural properties, oxidation, and solubility of proteins in the freeze-dried pork powder were investigated. In addition, the properties of the emulsion gels manufactured with freeze-dried pork powder (GFD) and freeze-thawed pork (GFT) at 1.5% and 2.0% NaCl were evaluated. The surface hydrophobicity and intrinsic tryptophan fluorescence intensity of myofibrillar proteins between the freeze-dried pork powder and freeze-thawed pork were similar. However, freeze-dried pork powder had higher carbonyl compounds and lower solubility of sarcoplasmic and myofibrillar proteins than freeze-thawed pork (p<0.05). GFD had higher cooking loss than GFT in 2.0% NaCl, and lower hardness and a^* value of GFD were observed regardless of NaCl level (p<0.05). Moreover, GFD had higher malondialdehyde content than GFT at the two NaCl concentrations (p<0.05). Therefore, our study demonstrated that freeze-dried pork powder has lower functional properties than freeze-thawed pork as raw meat for comminuted meat products.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.182-188
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• 1991

The reactions of aniline with benzyl and phenacyl compounds are studied by the AM1 method. Two types of modeling were adopted: Cation-neutral, in which a proton is attached to the leaving group F and anion-neutral model, in which aniline was replaced by phenoxide with Cl as the leaving group. The cation-neutral model represented the reactvery well, reproducing the various solution-phase experimental results. In the benzyl system, the ${\pi}$-electrons of the two rings (X-ring in the nucleophile and Y-ring in the substrate) interact conjugatively in the transition state (TS) resulting in a bond contraction of the $C_{\alpha}-C_{Y1}$ bond (benzylic effect), whereas in the phenacyl system the ${\pi}$ electrons of the X-ring delocalizes more efficiently into the carbonyl group than into the Y-ring (resonance shunt effect) with a bond contraction of the $C_{\alpha}-C_{\beta}$ bond. The bond contraction in the benzylic effect was substantially greater than that in the resonance shunt effect. The TS was rather loose for benzyl while it was tighter for phenacyl system. Various bond length changes with substituents in the TS were, however, found to be irregular.

• Tuberculosis and Respiratory Diseases
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• v.61 no.4
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• pp.330-338
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• 2006

Background: The main factors associated with weight loss in patients with COPD are not well known. Since chronic inflammation and oxidative stress play a major pathogenic role in COPD, these factors may be responsible for the patients' weight loss. Therefore, this study measured the body mass index (BMI) in COPD patients and evaluated the variables, such as systemic inflammatory marker, oxidative stress and lung function, that correlate with the BMI. Method: The stable COPD patients (M:F=49:4, mean age=$68.25{\pm}6.32$) were divided into the lower (<18.5), normal (18.5-25) and higher (>25) BMI group. The severity of the airway obstruction was evaluated by measuring the $FEV_1$. The serum IL-6 and TNF-$\alpha$ levels were measured to determine the degree of systemic inflammation, and the carbonyl protein and 8-iso-prostaglandin $F_2{\alpha}$ level was measured to determine the level of oxidative stress. Each value in the COPD patients and normal control was compared with the BMI. Results: 1) Serum 8-iso-prostaglandin $F_2{\alpha}$ in COPD patients was significantly higher ($456.08{\pm}574.12pg/ml$) than that in normal control ($264.74{\pm}143.15pg/ml$) (p<0.05). However, there were no significant differences in the serum IL-6, TNF-$\alpha$, carbonyl protein between the COPD patients and normal controls. 2). In the COPD patients, the $FEV_1$ of the lower BMI group was significantly lower ($0.93{\pm}0.25L$) than that of the normal BMI ($1.34{\pm}0.52L$) and higher BMI groups ($1.72{\pm}0.41L$) (p<0.05). The lower $FEV_1$ was significantly associated with a lower BMI in COPD patients (p=0.002, r=0.42). The BMI of very severe COPD patients was significantly lower ($19.8{\pm}2.57$) than that of the patients with moderate COPD ($22.6{\pm}3.14$) (p<0.05). 3). There were no significant differences in the serum IL-6, TNF-$\alpha$, carbonyl protein and 8-iso-prostaglandin $F_2{\alpha}$ according to the BMI in the COPD patients. Conclusion: The severity of the airway obstruction, not the systemic inflammatory markers and oxidative stress, might be associated with the BMI in stable COPD patients. Further study will be needed to determine the factors associated with the decrease in the BMI of COPD patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.570-576
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• 2013

The purpose of this study was to investigate the effect of turmeric on antioxidative systems and oxidative damage in rats fed a high fat and cholesterol diet. A total 40 rats were divided into four experimental groups: a normal diet group (N), a high fat and cholesterol diet group (HF), a high fat and cholesterol diet group supplemented with 2.5% turmeric powder (TPA group) and a high fat and cholesterol diet group supplemented with 5% turmeric powder (TPB group). The serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activity of the turmeric supplemented groups were decreased compared to the HF group. The GPT activity of the TPB group was especially and significantly decreased compared to the HF group. Hepatic superoxide dismutase (SOD) of the TPB group was significantly increased compared to the HF group. However, there were no significant differences in the activities of hepatic glutathione peroxidase (GSHpx) and catalase (CAT) among all experimental groups. Hepatic glutathione S-transferase (GST) activity in the TPA and TPB groups were increased compared to the HF group. Hepatic superoxide radical content in mitochondria of the 5% turmeric supplemented group was significantly decreased compared to the HF group. Hepatic hydrogen peroxide content in the cytosol and mitochondria of the turmeric-supplemented groups were decreased compared to the HF group. Hepatic carbonyl values in the mitochondria of the turmeric supplemented groups were significantly decreased compared to the HF group. Thiobarbituric acid reaction substance (TBARS) values in the liver were significantly reduced in turmeric supplemented groups compared to the HF group. These result suggest that turmeric powder may reduce oxidative damage through the activation of antioxidative defense systems in rats fed high fat and cholesterol diets.

• BMB Reports
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• v.32 no.4
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• pp.370-378
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• 1999

The effects of carnosine and related compounds (CRC) including anserine, homocarnosine, histidine, and ${\beta}$-alanine, found in most mammalian tissues, were investigated on in vitro glucose oxidation and glycation of human serum albumin (HSA). Carnosin and anserine were more reactive with D-glucose than with L-lysine. In the presence of $10\;{\mu}M$ Cu (II), although carnosine and anserine at low concentrations effectively inhibited formation of ${\alpha}$-ketoaldehyde from D-glucose, they increased generation of $H_2O_2$ in a dose-dependent manner. Carnosine, homocarnosine, anserine, and histidine effectively inhibited hydroxylation of salicylate and deoxyribose degradation in the presence of glucose and $10\;{\mu}M$ Cu (II). In the presence of 25 mM D-glucose, copper and ascorbic acid stimulated carbonyl formation from HSA. Except for ${\beta}$-alanine, CRC effectively inhibited the copper-catalyzed carbonyl formation from HSA. The addition of 25 mM D-glucose and/or $10\;{\mu}M$ Cu (II) to low density lipoprotein (LDL) increased formation of conjugated dienes. CRC effectively inhibited the glucose and/or copper-catalyzed LDL oxidation. CRC also inhibited glycation of HSA as determined by hydroxymethyl furfural and lysine with free ${\varepsilon}$-amino group. These results suggest that CRC may play an important role in protecting against diabetic complications by reacting with sugars, chelating copper, and scavenging free radicals.

• Polymer(Korea)
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• v.27 no.3
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• pp.249-254
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• 2003

The variation of chemical structure and physical properties of crosslinked polyethylene (XLPE) during thermal aging process was investigated. The formation of carbonyl functional group resulting from thermal oxidation reaction of XLPE was monitored using X-ray photoelectron spectroscopy and near infrared (NIR) spectroscopy. It was observed that the intensity of carbonyl peak observed at 1715 nm linearly increased with aging time in NIR spectroscopy. The linear relationship between NIR peak absorbance and aging time confirmed that NIR spectroscopy might be used as a proper tool for monitoring the aging process of polymeric materials. Also the formation of crosslinks during the aging process was monitored using thermal mechanical analysis, stress-strain test, and Shore hardness test. The change in the physical properties, such as the increase in the glass transition temperature from 110 to 132$^{\circ}C$, the decrease in the strain from 265 to 110%, as well as the increase in the shore D hardness from 32 to 50, was observed during the aging process.

• Journal of Photoscience
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• v.10 no.1
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• pp.9-20
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• 2003

Recent studies on the photoreactivity of l,4-unsaturated systems have changed some ideas that were firmly established in this area of research for many years. Thus, we have described the first examples of 2-aza-di-$\pi$-methane (2-ADPM) rearrangements promoted by triplet-sensitization and by single electron transfer (SET) using electron-acceptor sensitizers. These reactions afford N-vinylaziridine and cyclopropylimine photoproducts in the first examples of di-$\pi$-methane processes that yield three-membered ring heterocycles. l-Aza-1,4-dienes also undergo SET-promoted l-aza-di-$\pi$-methane (l-ADPM) rearrangements via radical-cation intermediates using electron acceptor sensitizers. In some cases, alternative cyclizations yielding different carbocycles and heterocycles have been observed. The l-ADPM and di-$\pi$-methane (DPM) reactions also occur via radical-anion intermediates on irradiation using electron donor sensitizers. On the other hand, the photoreactivity reported for $\beta$,${\gamma}$-unsaturated aldehydes for many years was decarbonylation to the corresponding alkenes. However, our studies demonstrate that these compounds undergo the oxa-di-$\pi$-methane (ODPM) rearrangement with high chemical and quantum efficiency. A comparison of the photochemical reactivity of $\beta$,${\gamma}$-unsaturated aldehydes and corresponding methyl ketones has shown that the ketones do not undergo the ODPM rearrangement while the corresponding aldehydes are reactive by this pathway. Monosubstituted $\beta$,${\gamma}$-unsaturated aldehydes at C-2 undergo the ODPM rearrangement yielding the corresponding cyclopropane carbaldehydes diastereoselectively. Finally, we have described the first examples of reactions, similar to the well know Norrish Type I process, which take place in the triplet excited state of $\beta$,${\gamma}$-unsaturated carbonyl compounds by excitation of the C-C double bond instead of the carbonyl group.

• Macromolecular Research
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• v.12 no.4
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• pp.367-373
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• 2004

We have developed a rigorous heat treatment method to improve the biocompatibility of chitosan as a tissue-engineered scaffold. The chitosan scaffold was prepared by the controlled freezing and lyophilizing method using dilute acetic acid and then it was heat-treated at 110$^{\circ}C$ in vacuo for 1-3 days. To explore changes in the physicochemical properties of the heat-treated scaffold, we analyzed the degree of deacetylation by colloid titration with poly(vinyl potassium sulfate) and the structural changes were analyzed by scanning electron microscopy, Fourier transform infrared (FT-IR) spectroscopy, wide-angle X-ray diffractometry (WAXD), and lysozyme susceptibility. The degree of deacetylation of chitosan scaffolds decreased significantly from 85 to 30% as the heat treatment time increased. FT-IR spectroscopic and WAXD data indicated the formation of amide bonds between the amino groups of chitosan and acetic acids carbonyl group, and of interchain hydrogen bonding between the carbonyl groups in the C-6 residues of chitosan and the N-acetyl groups. Our rigorous heat treatment method causes the scaffold to become more susceptible to lysozyme treatment. We performed further examinations of the changes in the biocompatibility of the chitosan scaffold after rigorous heat treatment by measuring the initial cell binding capacity and cell growth rate. Human dermal fibroblasts (HDFs) adhere and spread more effectively to the heat-treated chitosan than to the untreated sample. When the cell growth of the HDFs on the film or the scaffold was analyzed by an MTT assay, we found that rigorous heat treatment stimulated cell growth by 1.5∼1.95-fold relative to that of the untreated chitosan. We conclude that the rigorous dry heat treatment process increases the biocompatibility of the chitosan scaffold by decreasing the degree of deacetylation and by increasing cell attachment and growth.

• Bulletin of the Korean Chemical Society
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• v.14 no.1
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• pp.137-143
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• 1993

The tetranuclear heterometallic complex CpMo$Os_3(CO)_{10}({\mu]-H)2[{\mu}3-{\eta}^2-C(O)CH_2Tol]\;(1,\;Cp={\eta}^5-C_5H_5,\;Tol=p-C_6H_4Me)$ has been examined by variable-temperature $^{13}$C-NMR spectroscopy and by a full three-dimensional X-ray structual analysis. Complex 1 crystallizes in the orthorhombic space group Pna2$_1$ with a = 12.960(1) ${\AA}$, b = 11.255(l) ${\AA}$, c = 38.569(10)${\AA}$, V = 5626(2) ${\AA}^3$ and ${\rho}$(calcd) = 2.71 gcm$^{-3}$ for Z = 8 and molecular weight 1146.9. Diffraction data were collectedon a CAD4 diffractometer, and the structure was refined to $R_F$ = 9.7% and $R_{W^F}$ = 9.9% for 2530 data (MoK${\alpha}$ radiation). There are two essentially equivalent molecules in the crystallographic asymmetric unit. The tetranuclear molecule contains a triangulated rhomboidal arrangement of metal atoms with Os(2) and Mo at the two bridgehead positions. The metal framework is planar; the dihedral angle between Os(l)-Os(2)-Mo and Os(3)-Os(2)-Mo planes is 180$^{\circ}$. A triply bridging (${\mu}_3,\;{\eta}^2$) acyl ligand lies above the Os(l)-Os(2)-Mo plane; the oxygen atom spans the two bridgehead positions, while the carbon atom spans one bridgehead position and an acute apical position. The molecular architecture is completed by an ${\eta}^5$-cyclopentadienyl ligand and a semi-triply bridging carbonyl ligand on the molybdenum atom, and nine terminal carbonyl ligands-four on Os(3), three on Os(l), and two on Os(2). The two hydride ligands are inferred to occupy the Os(l)-Os(2) and Mo-Os(3) edges from structural and NMR data.

• Polymer(Korea)
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• v.38 no.1
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• pp.1-8
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• 2014

The effects of surface color and morphology on the mar behaviors of urethane-acrylate coated surfaces were examined. The superiority of mar resistance was observed in the order of white, red and black-colored samples. This can be explained by a contrast effect. In other words, in case of black colored sample, it takes place the defuse reflection of the incident light on the damaged region where mar damage exerts, leading to whitening phenomenon. Therefore, the damaged region is easily recognized by contrasting the black background. On the other hand, it is difficult for the white-colored sample to perceive the mar-damaged area by the white background acting as protecting coloration. As the gloss of urethane-acrylate coated surface increases, it is observed that there is an increase in the number of carbonyl (-C=O) function group, amount of ethylene and silica. The enhancements of surface rigidity by adding the silica particles and formation of carbonyl function groups by the surface oxidation lead to the increase in mar resistance, while the increase of polyethylene wax is responsible for the improved gloss and smooth-faced surface. Based on the above findings, technical approaches leading the improvement of mar resistance of the urethane-acrylate coated surface are discussed.