• Food Science and Biotechnology
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• 제18권4호
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• pp.900-903
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• 2009

An oat gum was extracted from whole seeds of a drought harvested oat (Avena sativa). Oat gum presented a ${\beta}-glucan$ content of 65%(w/w) and an intrinsic viscosity of 141 mL/g. Gelling capability of oat gum at different concentrations was investigated. Gel hardness increased from 0.08 to 0.25 N as the oat gum concentration changed from 5 to 10%(w/v). Whippability, foam stability, emulsion stability, and reduced viscosity of oat gum at different pH were also investigated. Oat gum whippability was maximum at pH 7 (146%), while the higher foam and emulsion stability values were found at pH 9 (88 and 96%, respectively). The gum reduced viscosity increased from 715 to 958 mL/g as the pH changed from 7 to 9. Oat gum shows great potential as a gel forming, thickening, and stabilizing agent.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.3-6
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• 2001

In common globular proteins, the native form is in its most stable state. However, the native form of inhibitory serpins (serine protease inhibitors) and some viral membrane fusion proteins is in a metastable state. Metastability in these proteins is critical to their biological functions. Our previous studies revealed that unusual interactions, such as side-chain overpacking, buried polar groups, surface hydrophobic pockets, and internal cavities are the structural basis of the native metastability. To understand the mechanism by which these structural defects regulate protein functions, cavity-filling mutations of a 1-antitrypsin, a prototype serpin, were characterized. Increasing conformational stability is correlated with decreasing inhibitory activity. Moreover, the activity loss appears to correlate with the decrease in the rate of the conformational switch during complex formation with a target protease. We also increased the stability of a 1-antitrypsin greatly via combining various stabilizing single amino acid substitutions that were distributed throughout the molecule. The results showed that a substantial increase of stability, over 13 kcal/mol, affected the inhibitory activity with a correlation of 11% activity loss per kcal/mol. The results strongly suggest that the native metastability of proteins is indeed a structural design that regulates protein functions and that the native strain of a 1-antitrypsin distributed throughout the molecule regulates the inhibitory function in a concerted manner.

• E2M - 전기 전자와 첨단 소재
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• 제14권12호
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• pp.3-6
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• 2001

In common globular proteins, the native form is n its most stable state. However, the native form of inhibitory serpins (serine protease inhibitors) and some viral membrane fusion proteins is in a metastable state. Metastability in these proteins is critical to their biological functions. Our previous studies revealed that unusual interactions, such as side-chain overpacking, buried polar groups, surface hydrophobic pockets, ad internal cavities are the structural basis of the native metastability. To understand the mechanism by which these structural defects regulate protein functions, cavity-filling mutations of $\alpha$1-antitrypsin, a prototype serpin, were characterized. Increasing conformational stability is correlated with decreasing inhibitory activity. Moreover, the activity loss appears to correlate with the decrease in the rate of the conformational switch during complex formation with a target protease. We also increased the stability of $\alpha$1-antitrypsin greatly via combining various stabilizing single amino acid substitutions that were distributed throughout the molecule. The results showed that a substantial increase of stability, over 13 kcal/mol, affected the inhibitory activity with a correlation of 11% activity loss per kcal/mol. The results strongly suggest that the native metastability of proteins is indeed a structural design that regulates protein functions and that the native strain of $\alpha$1-antitrypsin distributed throughout the molecule regulates the inhibitory function in a concerted manner.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.3-6
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• 2001

In common globular proteins, the native form is in its most stable state. However, the native form of inhibitory serpins (serine protease inhibitors) and some viral membrane fusion proteins is in a metastable state. Metastability in these Proteins is critical to their biological functions. Our previous studies revealed that unusual interactions, such as side-chain overpacking, buried polar groups, surface hydrophobic pockets, and internal cavities are the structural basis of the native metastability. To understand the mechanism by which these structural defects regulate protein functions, cavity-filling mutations of ${\alpha}$1-antitrypsin, a prototype serpin, were characterized. Increasing conformational stability is correlated with decreasing inhibitory activity. Moreover, the activity loss appears to correlate with the decrease in the rate of the conformational switch during complex formation with a target protease. We also increased the stability of ${\alpha}$1-antitrypsin greatly via combining various stabilizing single amino acid substitutions that were distributed throughout the molecule. The results showed that a substantial increase of stability, over 13 kcal/mol, affected the inhibitory activity with a correlation of 11% activity loss per kcal/mol. The results strongly suggest that the native metastability of proteins is indeed a structural design that regulates protein functions and that the native strain of e 1-antitrypsin distributed throughout the molecule regulates the inhibitory function in a concerted manner.

• 통합자연과학논문집
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• 제15권4호
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• pp.137-144
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• 2022

This paper presents the effect of the supramolecular complex of GA (Glycyrrhizic acid) and Mt(menthol) and GA: Mt (4: 1) obtained on their basis can restore functional dysfunction of the liver mitochondria in alloxan diabetes, ie, inhibit lipid peroxidation. The hypoglycemic activity and mitochondrial membrane stabilizing properties of the supramolecular compound GA: Mt (4: 1) in alloxan diabetes were more pronounced than those of menthol, GA and its GK: Mt (2: 1) and GA: Mt (9: 1) compounds. According to the results obtained, the concentration of GA did not affect the peroxidation of lipid membranes of the liver mitochondria. However, a concentration of 15 μM of GA was found to reduce LPO (lipid peroxidation) formed by the effect of Fe²+ / ascorbate on the mitochondrial membrane by 58.0 ± 5.0% relative to control. The inhibitory effect of GA and its supramolecular compounds in different proportions with menthol on the peroxidation of lipids in rat heart and brain tissue has been studied

• Preventive Nutrition and Food Science
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• 제3권4호
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• pp.382-386
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• 1998

A soluble dietary fiber, $\beta$-glucan, contained in oat and barley has nutritional benefits such as hypocholesterolemic effects and influences blood glucose regulation. The contents of $\beta$-glucan in both cereals range from 3 to 7% with the exception of a certain barley genotype which contains up to 16% $\beta$-glucan. $\beta$-Glucan is distributed mainly in the cell walls of endosperm and the distal (bran) portion of kernel. Various procedures have been developed for increasing the extraction yield of $\beta$-glucan. Oat gum prepared with weak alkali extractionand alcohol proecipitation following protein removal usually contains 80% $\beta$-glucan.The most commonly used method for $\beta$-glucan quantitiation is an enzymatic procedure combining lichenase plus $\beta$-glucosidase followed by measuring the amount of glucos released by glucose oxidase-peroxidase treatment. The increase in foam-and emulsion-stabilizing capacity of $\beta$-glucan is due to the increase in viscosity of the aqueous phase. Therefore, $\beta$-glucan shows great potentials as a thickener and a stabilizer.

• 한국염색가공학회지
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• 제17권3호
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• pp.26-33
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• 2005

EVA microsphere was prepared by a thermally induced phase separation. EVAL microsphere was made by a saponification on sheath of EVA microsphere. And microcapsule with EVA core-PU shell structure was synthesized by interfacial polymerization using diisocyanates with PEG in gelatin aqueous solution as the stabilizing agent. The effects of chemical structure of diisocyanate on the average particle size and distribution, morphology, color strength and friction fastness of core-shell particles were investigated to design microcapsule. The friction fastness of the fabrics printed with EVA core-PU shell microcapsules had the 4-5 grade.

• 소음진동
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• 제11권2호
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• pp.301-306
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• 2001

Electro-Rheological (ER) fluid is applied to a controllable squeeze film damper (SFD) for stabilizing a flexibly supported rotor system. ER fluid is a class of functional fluid whose yield stress varies according to the applied electric field strength, which is observed as viscosity variation of the fluid. In applying ER fluid to a SFD, a pair of rings of the damper can be used as electrodes. When the electrodes are divided into a horizontal pair and a vertical one, the SFD can produce damping force in each direction independently. A prototype of the directionally controllable SFD was constructed and its performance was experimentally and numerically investigated in the present work.

• 전기학회논문지
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• 제63권2호
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• pp.261-265
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• 2014

This paper studies the problem of the sampled-data control for Lur'e system with nonlinearities. The nonlinearities are expressed as convex combinations of sector and slope bounds. It is assumed that the sampling periods are arbitrarily varying but bounded. By constructing a new augmented Lyapunov-Krasovskii functional which have an augmented quadratic form with states as well as the nonlinear function, the stabilizing sampled-data controller gains are obtained by solving a set of linear matrix inequalities. The effectiveness of the developed method is demonstrated by numerical simulations.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.31-31
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• 2001

The native strain of serpins (serine protease inhibitors) has been recognized as a mechanism of biological regulation. Indeed, some stabilizing single residue mutations of human $\alpha$$_1$-antitrypsin, a prototype serpin, relieved local strain and caused the loss of inhibitory activity. The native strain of $\alpha$$_1$-antitrypsin is distributed throughout the whole molecule, but the strain that regulates the function directly is highly localized in the regions that appear to be mobilized during complex formation with a target protease.(omitted)