• Analytical Science and Technology
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• v.8 no.2
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• pp.181-186
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• 1995

The contents of sucrose and reducing sugars of cotyledons and hypocotyls of Ricinus communis L were increased slightly during cold treatment at $4^{\circ}C$. The concentration of total amino acids was increased continuosly during cold treatment. But the contents of hydrophilic amino acids, Asp/Asn, Glu/Gln, Thr, Ser, Ala and cationic amino acids, Arg and Lys were varied dramatically with the cold treated time. The cold treatment induced 24, 52, 54, 55, 56 and 73.5kD of proteins in cotyledons and 55, 56 and 73.5kD of proteins in hypocotyls. 24, 42, 49 and 52kD of proteins in cotyledons and hypocotyls were boiling stable. They were not denatrated by boiling at $100^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.93-97
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• 1986

Dried barley moodle was made with the addition of gelatinized corn flour as binder by using piston type noodle piston press, in which the temperature was kept below the temperature of protein denaturation. The evacuation of air bubble from the dough strengthened the wet noodle strands and improved the cooking quality of the dry noodle. Although the binder was indispensable, the addition should be less than 20%, because the gelatinized corn flour increased the turbidity of the cooking water. Kneading with 3% solution of soy protein resulted in improvement of the noodle's cooking quality.

• Journal of Life Science
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• v.8 no.2
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• pp.226-226
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• 1998

Discovery of molecular chaperone has stimulate cell biologists and thus made it possible to re-examine the processes whereby proteins achieve and maintain their functional conformations within living cells. the term ‘Molecular chaperone’ was first coined to describe one particular protein involved in the assembly of nucleosomes, but the term has now been extended to describe the function of a wide variety of proteins that assist protein transport across membranes, folding of nascent polypeptide, the assembly and disassembly of oligomeric structures, and the recovery or removal of proteins damaged by various environmental stresses including heat shock. Progress of molecular chaperone research is still limited by the lack of 3-dimensional structural information and detailed interacts with taget proteins in the cell. However, several laboratories around the world are attempting to extend our knowledge on the functions of molecular chaperone, and such efforts seem justified to finally provide the answers to the most burning questions shortly.

• Analytical Science and Technology
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• v.13 no.3
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• pp.346-350
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• 2000

Boiling stable proteins of 53 kDa and 29 kDa existed natively in the cotyledons of Bak Kyoung, fall radish (Raphanus raphanistrodes L.) Boiling stable proteins of 36 kDa and 16.5 kDa were newly induced by cold stress and the proteins of 53 kDa and 29 kDa increased during the cold stress. The proteins of 53 kDa were denatured within 2 hrs after removing cotyledons from plants. Boiling stable proteins of 53 kDa existed natively in the hypocotyls as much as in the cotyledons whereas 24 kDa and 18 kDa proteins were increased by stress. Boiling stable proteins of 53 kDa were induced and those of the 25 kDa and 23 kDa were increased by cold treatment and ABA treatment in the cotyledons of Jangchundaehyung F1 spring white (Raphanus raphanistrodes L.). These results showed the differences of induced boiling stable proteins between fall radishes and spring radishes. Cycloheximide inhibited the induction of 25 kDa and 23 kDa proteins during stress. 22 kDa native protein disappeared during ABA treatment and reappeared by cycloheximide treatments. It may be explained that cycloheximide was responsible for the destruction process of proteins in the living organisms. The profile of boiling stable proteins in hypocotyls of spring radishes during stress was same as that of fall redishes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.455-463
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• 1985

Thermal-denaturation of myofibrillar protein of dorsal skeletal muscle from file fish was investigated by measuring denaturation constant($K_D$) and thermodynamic parameters at various temperatures. The protective effects of sucrose, sorbitol and amino acids when added individually or combined were also discussed. The denaturation rate as reflected in inactivation of myofibrillar protein Ca-ATPase was followed the first order reaction. The $K_D$ values at $25^{\circ}C,\;30^{\circ}C,\;and\;35^{\circ}C$ were $19.52{\times}10^{-5},\;112.25{\times}10^{-5},\;and\;247.20{\times}10^{-5}$, respectively. The activation energy of the reaction at $30^{\circ}C$ was 43 kcal/mole. The protective effects of sucrose, sorbitol, glycine, alanine and Na-glutamate were increased with the concentration but the effects of sorbitol and Na-glutamate decreased beyond 1.0 mole. Basic amino acids such as arginine and lysine did not revealed any protective effect on the thermal denaturation. In case of mixed addition, the effects of Na-glutamate to glycine, sorbitol to glycine, and sorbitol to sucrose or sorbitol to Na-glutamate were enhanced 1.2 to 7.0 times as much as that of control (ratio of mixing; 1:1, range of concentration; 0.5 to 1.25 mole). Under the frozen condition at $-20^{\circ}C$, two mixtures such as Na-glutamate to glycine and sorbitol to sucrose apparently revealed the protective effects.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.331-336
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• 2002

Conformation of soymilk protein was examined to obtain basic information for improved calcium intolerence of soymilk protein partially hydrolyzed with protease. Surface hydrophobicities of three proteins showed the order of SMP(soymilk protein) < SPI(soy protein isolate) < PT-SMP(protease treated soymilk protein). Total thiol group contents of SMP and PT-SMP were similar but larger than that of SPI. Reducing rate of disulfide bond in PT-SMP after 2-mercaptoethanol treatment was laster than that in SMP. And so, this result indicates that PT-SMP may be less compacting due to protease treatement. From circular dichroism result, PT-SMP showed different pattern from SMP and SPI suggesting change of secondary structure by hydrolysis. And analysis of heat denaturating property by DSC showed that denaturation enthalpy of three proteins were all small. Especially enthalpy of PT-SMP was least, and this result suggested that PT-SMP was denatured easily by heating due to less compacting structure.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.423-429
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• 2005

Properties of pant surimi derived from porcine longissimus muscle were investigated Rapid glycolysis of muscle reduced yield $\%$ of water-washed pork and moisture $\%$ of pent surimi because of ie lower ultimate pH. Gel Hardness was significantly (p<0.05) higher in pork surimi from rapid glycolysis muscle, but springiness was higher (p<0.05) in pork surimi from normal glycolysis muscle. SDS-PAGE pattern showed denaturation of sarcoplasmic proteins onto myofibrillar proteins in rapid glycolysis muscle, resulted in dark color and hard texture of pork surimi. Color and texture of gels were related with water-holding capacity of muscle proteins and moisture $\%$ in gel matrix. Results imply that glycolysis rate of porcine muscle at postmortem could affect gel properties of pork surimi, and muscle with rapid glycolysis muscle could produce a hard texture of pork surimi and dark color.

• KSBB Journal
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• v.6 no.1
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• pp.105-109
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• 1991

In separating alkaline protease from the bacteria (Bacillus licheniformis) fermentation broth using reverse micelle, effects of various factors;ionic strength, pH and surfactant concentration, on separation efficiency were studied. KCl controls the ionic strength. The lower KCl concentration was in the feed solution, the more protein and activity was recovered. The higher KCl concentration was in the stripping solution, the more protein and activity was recovered. Using sodium-di-2-ethylhexyl sulfosuccinate(Aerosol-OT or AOT) as a surfactant, the higher AOT concentration in the solvent, the more activity and protein were recovered. 0.1N NaOH and IN HCl were used to adjust pH. Maximum recovery of protein mass and activity were obtained at feed solution of pH 5.3. Maximum activity was recovered at stripping solution of pH 7.5

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.536-541
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• 1989

In present paper, we investigated the quality stability of frozen seasoned anchovy meat products during storage at $-25\;{\pm}\;2^{\circ}C$. The pH and VBN contents of the products revealed a tendency to increase slightly during frozen storage 150 days. Viable cell counts and histamine contents of products are $0.8-2.6\;{\times}\;10^5/g,\;70.6-76.7 mg/100g$, respectively. In changes of fatty acid composition, percentage of polyenes such as eicosapentaenoic docosahexaenoic acid slightly decreased, while that of saturates and monoenes increased during frozen storage, The results of changes in POV, TBA values, color values, drips and salt extractable nitrogen contents during frozen storage showed that lipid oxidation and freeze denaturation of products could be retarded, and flavor could be enhanced by adding 0.2% sodium erythorbate and 12.8% emulsion curd.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.3_4
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• pp.101-111
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• 1973

To study the effect of freezing rate on the duality of frozen abalone(Haliotis gigantea, GMELIN) liquid nitrogen spray freezing, air blast freezing, semi-air blast freezing, and still air freezing were carried out. The rheological change, protein denaturation, and free water content of frozen and thawed abalone were examined at the period of 0, 1, 2, and 3 month during cold Storage at $-20^{\circ}C$. The results are summarized as follows : 1. The onset and duration of rigor mortis of fresh abalone was faster and shorter as compared to that of fishes. 2. There was no difference in compression value and shear value between freezing methods but they varied with a slight decrease in storage period. 3. Gradual decrease in extractibility of salt soluble protein was observed in all samples except those frozen with liquid nitrogen. 4. The free water of the foot muscle remained constant during the storage while that of the adductor muscle tended to increase. 5. A significant correlation was observed among the changes of panel texture and free water (P< 0.01), protein denaturation (P<0.05), and compression value (P<0.01).