• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.282-291
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• 2006

Effects of the molecular weight and type of chitosans on shelf-life of Makkulli were evaluated during 18 days of storage at $25^{\circ}C$. Two types of chitosans were studied: ${\alpha}$-chitosans with 11 different molecular weights (water-soluble, Mw = 1, 8, 22, 43, 67 and 616 kDa; acid-soluble, Mw = 282, 440, 746, 1,110 and 2,025 kDa) and ${\beta}$-chitosan (acid-soluble, Mw = 577 kDa). Acid-soluble chitosans were applied as a form of chitosan-ascorbate. All chitosans were added to Makkulli at 0.002% concentration, the optimum concentration established in a preliminary test. Among 12 chitosans, the ${\alpha}$-chitosans with 22 and 440 kDa exhibited stronger antimicrobial effects than did other ${\alpha}$- and ${\beta}$-chitosans. The results for pH, acidity, alcohol concentration, viable cell counts, and sensory evaluation suggested that addition of ${\alpha}$-chitosans with 22 and 440 kDa increased the shelf-life of Makkulli by almost 1 week at $25^{\circ}C$ compared with that of control (without chitosan) and other chitosan-added groups. Extension of Makkulli shelf-life by 1 week is fairly significant in view of the magnitude of the total amount of Makkulli produced in Korea.

• Journal of Life Science
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• v.27 no.7
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• pp.739-745
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• 2017

In all mammalian species, progesterone is essential in the preparation for and maintenance of pregnancy. $20{\alpha}$-hydroxysteroid dehydrogenase ($20{\alpha}$-HSD) predominantly converts progesterone into its biologically inactive form $20{\alpha}$-hydroxyprogesterone ($20{\alpha}$-OHP), and plays a crucial role in the termination of pregnancy and initiation of parturition. In this study, we characterized the expression and localization of $20{\alpha}$-HSDinthe testis of MediKinetics $Micropigs^{(R)}$. The testes were collected at days 6, 9, 12, 18, and 21 after birth. The $20{\alpha}$-HSD mRNA was found to be expressed in the testis at day 6 after birth by RT-PCR. The highest level of mRNA expression in the testis was detected on day 21 after birth. However, the mRNA was not detected in the placenta after parturition. Western blot for $20{\alpha}$-HSD reveal that the specific 37-kDa band was detected in immature pig testis. However, this band was not detected in testis tissue at day 6 after birth. In the immunohistochemical analysis of the testis, $20{\alpha}$-HSD was detected in the Sertoli cells and Leydig cells. Taken together, our study shows for the first time that the $20{\alpha}$-HSD mRNA and protein are expressed in pig testis after birth. Further investigation is required to elucidate the functional mechanisms of $20{\alpha}$-HSD in pig testis after birth.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.803-811
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• 2003

This study compared the physicochemical characteristics of yellow pigments in domestic and imported yellow croakers during distribution and storage. The croaker is generally adulterated by mixed color product of red and yellow pigment. This study found that the yellow pigment was stable during pH and temperature changes, but the red pigment was less stable than the yellow pigment. As for the light effect on the yellow pigment and the red pigment, there was no change in the remaining rate of the pigment stored in a dark place. The moisture content decreased according to the storage period, and the width of changes was large in the order of croaker stored at $5^{\circ}C$, croaker stored at $15^{\circ}C$ and dried croakers. The yellowness value of the abdomen of the adulterated white croaker did not show any large difference at the initial stage and for a storage period of 10 days at $5^{\circ}C$. However, the yellow croakers showed a decreasing trend according to the storage period at $15^{\circ}C$. The croaker can be generally adulterated by a mixed color of red and yellow pigment. For the texture change in accordance with the storage condition of the croakers, both the yellow and white croakers showed a gradually increasing trend of hardness when stored at $5^{\circ}C$ and $15^{\circ}C$.

• Journal of Aquaculture
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• v.19 no.3
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• pp.173-177
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• 2006

This study was conducted to evaluate extruded pellets (EP) for growth of adult flounder by comparing with raw fish-based moist pellet (MP). Two replicate groups of 150 fish per each tank (initial mean weight 329 g) were fed one of seven EP (EP1, EP2, EP3, EP4, EP5, EP6 and EP7) and a MP for 8 months. Survival of fish fed the MP was not significantly different from that of fish fed the EP1, EP5 and EP7, but significantly higher than that of fish fed the EP2, EP3, EP4 and EP6 (P<0.05). Weight gain of fish fed the MP was significantly lower than that of fish fed the EPI (P<0.05), but not significantly different from that of fish fed EP2, EP3, EP4, EP5, EP6 and EP7. Feed efficiency of fish fed the MP was significantly lower than EP1, EP3, EP4, EP5 and EP6 (P<0.05), but not significantly different from that of fish fed EP2 and EP7 Feed supply (kg/tank) of fish fed the MP was significantly higher than that of fish fed all EP (P<0.05). Condition factor of fish fed the MP was not significantly different from that of fish fed all EP. The contents of moisture, crude protein and lipid in dorsal muscle and whole body was not significantly different among the groups. It is concluded that the dietary formulation used in the EP1, EP3, TP4, EP5 and EP6 can be applied in the practical extruded pellet feeds for adult flounder (329-680g).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.2 s.57
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• pp.105-110
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• 2006

This study was to describe the differences in efficacy and effect of herbal extracts by the part and solvent extraction from the medical plants used as materials of oriental herbs cosmetics. And, this study was to apply to the test method of efficacy and effect related to the antioxidation as herbal extracts, complex of actual ingredient, not existing analytical methods of single ingredient. After screening the medical plants with the antioxidative activity primarily and selecting 11 sorts of medical plants to be used by the part in the literature, this study was to confirm the differences through the well-known test methods like DPPH radical scavenging activity test and hydroxyl radical scavenging activity test. For examples, in case of Trachelospermum asiaticum, compared with the aerial part and fruit, the value of DPPH radical scavenging activity test had $25.2 {\pm} 0.2$ and $62.4 {\pm}1.6$ each. It has shown that the value of fruit had 2.4 times higher effect than the one of aerial part. In case of hydroxyl scavenging activity test, it was effective in the fruit, but it has shown that there was no effect on the aerial part. It showed the same phenomena in some other plants. From the result above, this researcher could understand that it needed to consider extracting the medical plants or plants with the active principle by the part. Also, this study was to confirm the differences in effect according to the solvent as it changed the solvent extraction after selecting a plant (Lithospermum erythrorhizon) widely used for medicine and dye. As a result of measuring the actual value of superoxide scavenging activity test, this study was to consider that there were differences by the part or solvent extraction in extracting and using the medical plants as it has shown that the effect differences produced $10{\sim}80%$ according to the solvent. When it was applied to the products, this study has shown that it needed to decrease the possible errors.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.229-233
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• 2016

This study was conducted to compare three commercially available egg testing devices for measuring egg quality. The devices used were a Laser-type (automatic), a Ultrasonic-type (automatic), and a Probe-type (manual). Fresh eggs weighing 60~68 grams were obtained from a commercial hen farm. Three trials were conducted. In Trial 1, a total of 50 eggs were successively analyzed by the three egg testing devices. In Trial 2, fresh eggs were successively analyzed by a combination of two egg testing devices. In Trial 3, a total of 600 eggs (weighing 60~68 grams) laid by same flock were selected, further divided into three sub-groups with a total of 200 eggs, and analyzed by an egg testing device. In Trials 1 and 2, no apparent difference was observed in egg weight between egg testing devices. However, albumin height was scored highest in the Ultrasonic-type egg tester followed by the Probe-type and Laser-type (Trials 1 and 2). Consequently, the Haugh unit was similarly altered. Yolk color was highest in the Laser-type egg tester followed by the Ultrasonic-type and Probe-type (Trials 1 and 2). When fresh eggs laid by a single flock were independently analyzed by three devices, egg weight did not differ, but albumin height and Haugh unit were higher (p<0.05) in the Ultrasonic-type egg tester than in the Probe-type or Laser-type testers. However, Laser-type testers produced higher (p<0.05) yolk color values than the Ultrasonic-type or Probe-type egg testers. In conclusion, the commercially available egg testing devices exhibited performance differences in measuring egg qualities, which warrants further consideration as to whether the magnitude of bias and precision between the devices could be acceptable in the egg grading system, especially when assessing eggs stored for certain durations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.273-279
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• 2000

The influence of different storage temperature and packaging methods on plain dried anchovy were investigated. When plain dried large anchovy (DLA) was stored at $-20^{\circ}C, 5^{\circ}C and 2^{\circ}C$, the lipid oxidation was rapidly progressed with the increased temperature. When DLA was stored at $25^{\circ}C and 5^{\circ}C$, peroxide value (POV) reached to maximum on 4 days and 20 days, respectively, while POV increased progressively during storage at $-25^{\circ}C$. The degree of lipid oxidation was progressed the fastest in DLA packed in polyethylene film, followed by packing with oxygen absorber and packing in vacuum. The fatty acid composition of total lipid in DLA revealed $52.3{\%}$ in polyenes, $29.2{\%}$ in saturates and 1$8.5{\%}$ in monoenes, and the major fatty acids were 22 : 6, 20 : 5, 16 : 0, 16 : 1 and 18: 1. Saturates were increased with the rise of storage temperature and prolonging the storage period, while polyenes were decreased. The changes of fatty acid composition was retarded at lower temperature. And the changes of fatty acid composition were the lowest in DLA by vacuum packing, followed by packing with oxygen absorber and packed in polyethylene film. The contents of highly unsaturated fatty acid of polyenes were decreased remarkably in proportion to the progress of lipid oxidation, while saturates were increased.

• Journal of Life Science
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• v.25 no.3
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• pp.329-335
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• 2015

This study was performed to determine the optimal ratio of Petasites japonicus, Luffa cylindrica, and Houttuynia cordata, all of which are supposed to have anti-respiratory disease effects, such as against rhinitis. The experiment incorporated a mixture design and included 12 experimental points with center replicates for three different independent variables (Petasites japonicus 30~70%; Luffa cylindrica 10~30%; and Houttuynia cordata 10~30%). Based on this design, the mixture was extracted in hot water at 121℃ for 45 min and anti-allergy and anti-microbial activities were observed. The response surface and trace plot described for the anti-allergy activity showed Petasites japonicas was a relatively important factor. The correlation coefficient (R²) value 82.10% for the inhibition effect of degranulation was analyzed by the regression equation. The analysis of variance showed the model fit was statistically significant (p<0.05). The optimal ratio of the mixture was Petasites japonicus 0.75%, Luffa cylindrica 0.11%, and Houttuynia cordata 0.14%. The anti-microbial activity for each extraction of the mixture was valid on gram-positive, such as Staphylococcus aureus (KCCM 40881) and Staphylococcus epidermidis (KCCM 35494), while it was less effective on gram-negative, such as Escherichia coli (KCCM 11234) and Pseudomonas aeruginosa (KCCM 11328).

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.3
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• pp.178-185
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• 2006

This study was to investigate the effect of 0.1% chitosan-ascorbate (CA) prepared with different molecular weight (223, 746, 1,110 and 2,025 kDa) of chitosan on the changes in antioxidant activity of mul-kimchi during storage at $10^{\circ}C$ for 20 days. Animal experiments were divided to 5 groups; normal control group (NC), high cholesterol diet group (HC), high cholesterol diet mul-kimchi diet group (HCKC), high cholesterol diet and CA2025 containing mul-kimchi administrated group (HCCA), and high cholesterol diet and 1/2 concentrated CA containing mul-kimchi administrated group (HC2CA). Mul-kimchi juice was administered 0.5 mL per 100 g body weight once a day and fed for 5 weeks. Electron donating activity of the 20 days-stored mul-kimchi with 0.1% CA showed higher activity (84.74~89.13%) than those of control and ascorbic acid mul-kimchi (35.04 and 75.04%). Superoxide dismutase activities of the kimchijuice with CA were higher in the higher molecular of chitosan. In the animal experiments, the average body weight of the HCCA and HC2CA group were lower 6.9% and 8.4% than that of HC control group, respectively. Hepatic glutathione content in HCCA and HC2CA group was increased 22.5% and 9.1% as compared to HC group. Hepatic glutathione S-transferase activities were significantly increased in the HCCA (219.9%) and HC2CA group (153.8%) compared to NC group. Hepatic superoxide dismutase activity was highest in the HCCA group, and the activities in CA groups were higher than those of NC and HC group.

• Journal of Life Science
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• v.21 no.4
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• pp.604-609
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• 2011

Pine (pinus densiflora) needles have long been used as a traditional health-promoting medicinal food in Korea. This study was conducted to investigate the effects of pine needle extracts on the hepatic antioxidant system in the damaged liver of carbon tetrachloride ($CCl_4$)-treated rats. Nine-week-old Sprague Dawley rats were divided into four groups: normal group (NOR), $CCl_4$-treated group (CCL), pine needle hot water extract and $CCl_4$-treated group (CCL-P), and Vitamin C and $CCl_4$-treated group (CCL-V). The enzyme activities and antioxidant effects of the pine needle hot water extracts were investigated at the levels of liver homogenates and serum of rats intoxicated with $CCl_4$. Serum GOT and GPT activities by $CCl_4$ treatment increased compared to those of the NOR group. However, they tended to decrease in the hot water extract-administered group. Liver SOD activity in the CCL group was significantly lower than the NOR group (p<0.05). However, they increased in the CCL-P group compared to the CCL group. Further, the CAT and GPx activities of serum treated with $CCl_4$ were higher compared to those of the NOR group but lower in the CCL-P group compared to CCL group. These results suggest that pine needle hot water extract increases antioxidant activities.