• Proceedings of the Korean Vacuum Society Conference
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• 2008.08a
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• pp.74-74
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• 2008

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.251.2-251.2
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• 2001

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.272.1-272.1
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• 2001

• Journal of Dairy Science and Biotechnology
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• v.39 no.1
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• pp.36-50
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• 2021

This study aimed to evaluate the biological potential of functional food, i.e., specific peptides obtained from the hydrolysis of milk protein, by assessing their antioxidant and antibacterial properties. For the preparation of casein hydrolysates, commercial enzymes were added to 10% casein solution in a 1:200 (w/v) ratio, and samples were collected each hour. Based on the assessment of the degree of hydrolysis (DH) of casein hydrolysates, it was observed that the concentration of all enzymatic hydrolysates increased rapidly from 30 to 40 minutes. However, no change was observed in their concentrations after 150 minutes. Protamex® and Neutrase® exhibited the highest DH when compared to other enzymes. Furthermore, SDS-PAGE was performed for analyzing the proteolytic pattern of each enzyme, except for Flavourzyme®, and peptides in the size range of 20-25 kDa were identified. Subsequently, peptides produced by two enzymes were isolated using a preparative liquid chromatography system. Overall, NF3, NF4, PF5, and PF6 showed higher antioxidant potential than other peptide fractions. Moreover, NF7 and PF3 exhibited the highest antibacterial activity. In this study, we evaluated the biological potential of novel casein-derived peptides that may find application in the food and healthcare industry.

• Journal of Korean Society of Steel Construction
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• v.8 no.4 s.29
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• pp.133-133
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• 1996

Application of the relationship $da/dN=C({\Delta}K)^{m}$ is effective in the analysis of fatigue crack growth life. The values of material constant C and m have great influences on the predicted fatigue life and the relationship between fatigue crack growth rate(da/dN) and stress intensity factor range(${\Delta}K$) is effective in fatigue crack growth behavior. In this paper, fatigue crack growth behavior of the welded joints in HT60 grade TMCP(Thermo Machanical Control Process) steel have been studied. To evalute the fatigue crack growth rates of HT60 grade TMCP steel, fatigue test was performed by base metal(BM), heat affected zone(HAZ) and weld metal(WM) in TMCP steel at room temperature. We determined the relationship of $da/dN-{\Delta}K$ by correlation between C and m obtained from the Paris-Erdogan power law data supplied HT60 grade TMCP steel. The obtained results from this study indicate that fatigue crack growth rate of TMCP steel is not influenced by softening effect which occurs in the HAZ when high heat input weld is carried out. Softening effects, which affect fatigue properties. are shown that it is not affected to the fatigue growth rates significantly.

• Journal of fish pathology
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• v.36 no.2
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• pp.389-394
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• 2023

Infectious hematopoietic necrosis virus (IHNV) is s significant viral pathogen affecting cultured rainbow trout (Oncorhynchus mykiss) in Korea. In this study, five monoclonal antibodies (mAbs) (IHNV-1, 2, 3, 4, and 5) were produced using purified IHNV. Reactivities of these mAbs were analyzed by western blot (WB), enzyme-linked immunosorbent assay (ELISA), and indirect fluorescent antibody test (IFAT). These mAbs recognized glycoprotein (69 kDa, IHNV-1), nucleocapsid protein (39 kDa, IHNV-3, 4, and 5), or phosphoprotein (27 kDa, IHNV-2) of IHNV by WB analysis. ELISA results indicated that these five mAbs were specific to IHNV without showing any cross-reactivity against other fish viruses (hirame rhabdovirus, infectious pancreatic necrosis virus, and viral hemorrhagic septicemia virus). IFAT demonstrated specific fluorescence signals of IHNV-infected epithelioma papulosum cyprini (EPC) cells, whereas no reactivity of normal EPC cells was observed. These mAbs can be very useful for immuno-diagnosis of IHNV infection.

• Journal of Nutrition and Health
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• v.39 no.3
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• pp.225-235
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• 2006

Although it has traditionally known that deer antler and medicinal herbs extract contain some functional components for health promotion, the nutritional significance remains to be elucidated. This study examined the efficacy of deer antler extract (DA) , medicinal herbs extract (MH) and their mixture (DAMH) on serum IGF-I, bone growth with growing rats in vivo and splenocyte proliferation with spleen cells in vitro. Three week-old young female rats (Sprague-Dawley) were divided into 4 groups and then fed basal diet (AIN-93G) or experimental diets containing DA, MH, DAMH, respectively, for 7 weeks. We collected blood, liver, kidney, spleen, femur and tibia from rats. There was no significant difference in weight gain, but food intake increased in DA- and MH-fed groups. There were no signs of liver and kidney damage in the DA, MH and DAMH-fed groups compared to basal diet group. In femur and tibia, wet weights: breaking forces and bone minerals (Ca, Mg and Zn) were significantly higher in the DA-fed group than in the other groups. Serum alkaline phosphatase (ALP) , bone-specific alkaline phosphatase (BALP) activities were significantly lower in the DA, MH, DAMH-fed groups than in basal diet group. Also, serum insulin-like growth factor-I (IGF-I) concentrations were significantly increased in DA-fed group compared to the other groups. Therefore DA was shown to have an activity of bone growth promotion by increasing the IGF-I, a major bone growth factor. The deer antler extract showed an enhanced immune action on the primary cultured-cells from spleen of rats, representing that splenocytes were proliferated by lipopolysaccharide (LPS), but not by concanavalin A (Con A). These results indicate that deer antler extract has beneficial effects on bone growth via IGF-I and on splenocyte activation.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.84-93
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• 2013

The aims of this study were to investigate and confirm the occurrence and distribution patterns of perfluorinated compounds (PFCs) in Nakdong River basin (mainstream and its tributaries). 7 (PFOS, PFHpA, PFOA, PFNA, PFDA, PFUnDA and PFDoDA) out of 11 PFCs were detected in 29 sampling sites and PFOA and PFHpA were predominant compounds in upstream, but PFUnDA, PFDoDA and PFOS were predominant compounds in middle stream of Nakdong River basin. The total concentration levels of PFCs on February 2009 and on August 2009 in surface water samples ranged from 4.3. to 1168.2 ng/L and 16.4 to 627.8 ng/L, respectively. The highest concentration level of PFCs in the mainstream and tributaries in Nakdong River were Goryeong and Jincheon-cheon, respectively. The sewage treatment plants (STPs) along the river affect the PFCs levels in river and the PFCs levels decreased with downstream because of dilution effects.

• Animal cells and systems
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• v.1 no.3
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• pp.457-462
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• 1997

Antibacterial activity was induced in the haemolymph of the common cutworm, Spodoptera litura by the artificial injection of E, coli Ek132. Antibacterial peptides were purified from the immunized haemolymph by heat treatment, ion-exchange chromatography, gel filtration chromatography, and reverse phase FPLC, and their physicochemical characteristics were investigated. These purified antibacterial peptides designated as spodopsin la and Ib were named after Spodoptera litura. Spodopsin la and Ib had the apparent molecular masses of 3, 823 Da and 3, 886 Da, respectively, and about 20% of the sequences had basic amino acids, such as lysine and arginine but no cysteine. Also, spodopsin l was confirmed to be a new member of cecropin family having a similar amino acid sequence to cecropin of lepidopteran insects, such as Bombyx mori and Hyalophora cecropia. The purified spodopsin was active against gram-positive as well as gram-negative bacteria.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.7
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• pp.168-177
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• 1999

Fatigue damage is the phenomena which is accumulated gradually with loading cycle in material. It is represented by fatigue crack growth rate da/dN and fatigue life ratio $N/N_{f}$. Fracture mechanical parameters estimating large crack growth behavior can calculate quantitative amount of fatigue crack growth resistance in engineering material. But fatigue damage has influence on various load, material and environment. Therefore, In this study, we propose that artificial intelligent fatigue damage model can predicts fatigue crack growth rate da/dN and fatigue life ratio $N/N_{f}$ simultaneously using fracture mechanical and nondestructive parameters.