• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.519-528
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• 1985

Fillets of mackerel (Scomber japonicus) and flounder (Xystrias grigorjewi) which, are representatives in red fleshed fish and white fleshed fish, respectively, were freeze-dried and stored in tightly sealed containers which were controlled to different relative humidity at $25^{\circ}C$. The changes of lipids were examined periodically by measuring the peroxide value (POV), the thiobarbituric acid (TBA) and the acid value (AV). And the fatty acid composition of lipids was investigated by gas-liquid chromatography (GLC). The results obtained are summarized as foollows: From the changes of POV and TBA value during storage, the oxidation of lipids was distinct at the lower relative humidities, $0\%\;and\;23\%$, while inhibited at the higher relative humidities, $52\%\;and\;81\%$. The changes in acid value during storage were more prominent at the hifger relative himidites than at the lower relative humidities. The content of $C_{16:0},\;C_{18:0}\;and\;C_{22:6}$ acids in the fatty acid composition of total lipids was abundant in both fleshed fishes. The content of $C_{18:1}$ acid in the nonpolar lipid and that of $C_{16:0}$ acid in the polar lipid were higher than other fatty acids. In the fatty acid composition of total lipids during storage, polyenoic acids decreased with storage period at $0\%\;and\;23\%$ relative humidities, while the fatty acid composition didn't show a great change at $52\%\;and\;81\%$ relative humidities. In the non-polar lipid, polyenoic acids coherently decreased under all the conditions of relative humidities but the saturated acids and the monoenoic acids increased. In the polar lipid, polyenoic acids decreased at $0\%\;and\;23\%$ relative humidities, while the saturated acids and monoenoic acids decreased at $52\%\;and\;81\%$ relative humidities. On the other hand, the oxidation of lipids was more significant in mackerel than in the flounder, and the changes of fatty acid composition were shown a similar pattern.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.285-292
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• 2013

This study was carried out to validate the safety of ametoctradin residues in agricultural commodities by developing an official analysis method. An analytical method was developed and validated using HPLC-PDA detectors. The samples were extracted with methanol, subsequently partitioned with dichloromethane and purified with florisil column chromatograph using acetone/hexane (30/70, v/v) as solvent. The method was validated by using grape, hulled rice, mandarin, and potato spiked with ametoctradin at 0.05 and 5.0 mg/kg, and pepper at 0.05 and 2.0 mg/kg. Average recoveries were 76-114.8% with relative standard deviation less than 10%, and the limit of detection and limit of quantification were 0.0125 and 0.05 mg/kg, respectively. The result of recoveries and overall coefficient of variation of the laboratory results from Gwangju regional Food and Drug Administration (FDA) and Daejeon regional FDA was accorded with Codex Alimentarius Commission Guideline (CAC/GL 40). Based on these results, this method was found to be appropriate for ametoctradin residue determination and can be used as the official method of analysis.

• Journal of Life Science
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• v.19 no.1
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• pp.58-64
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• 2009

This study was conducted to know the molting sequence and the aging points of flight feathers of steller's sea eagles (Haliaeetus pelagicus). For this study, two captive immature steller's sea eagles raised at the Ornithology Laboratory attached to Kyungsung University were surveyed for five years from Nov. 2000 to Nov. 2005. The survey indicated that the first molting began in July of the second year, and the primaries of P1-3, the secondaries of S18-19 (female), S17-18 (male), and S1 and S4 were replaced by one-time with second generation feathers. Generally molting stopped during the winter period, but a few feathers continued to molt during the winter. The two secondaries of S18-19 (female) and S17-18 (male) always molted every year but some of the juvenile secondaries (male: S10, S11, etc) retained for 2 or 3 years. In the molting order of primaries, the first molting started at P1 and it proceeded to P10 of outside. In the secondaries, the first molting started at S17(male) and S19(female), and it proceeded to outside. After that molting it started at S1 and proceeded to inside. In the other secondaries, the pattern of molting which proceeded in the mid-part of the secondaries was usually beginning in several different points at the same time. The molting seemed as if it depends on both the conditions of the individuals and the environment, so it was very difficult to explain the molting pattern in the mid-part of the secondaries. The longer quills (P7, P8) required for more than 68 days to develop. In the comparison of the length in the remiges between the first and the second generation feathers, the first generation feathers were the larger than that of the second. And the reduction of the length between the second and the third generation feathers was a few. The reduction of the length between the third and the fourth generation feathers was slight. The juvenile primaries were dark brown with a whitish base, which could be observed until the second or the third generation feathers (in their third or fourth winter plumage).

• Food Science of Animal Resources
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• v.33 no.3
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• pp.403-410
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• 2013

This study was performed to evaluate the microbiological contamination level of raw beef from retail markets in Seoul, Korea. The sampling and laboratory test were performed according to the procedure of "Standard for processing and ingredients specification of livestock product" and "Korean food code". Enterotoxin of Staphylococcus aureus isolates were detected using VIDAS$^{(R)}$ and PCR-based methods. Listeria monocytogenes serotyping and genotyping were carried out using Listeria antisera and L. monocytogenes Fingerprinting kit, respectively. A total of 48 samples were collected from 16 retail markets (butcher's shop: 5, department store: 6, supermarket: 5) in 2011. The level of total bacteria counts in the butcher's shop, department store and supermarket were $4.4{\times}10^3$ CFU/g, $3.9{\times}10^5$ CFU/g and $1.0{\times}10^4$ CFU/g, respectively. The concentrations of Escherichia coli of these three retail markets were $6.4{\times}10$ CFU/g, 7.6 CFU/g and $2.0{\times}10$ CFU/g, respectively. Salmonella species was not detected on all samples. However, S. aureus was isolated in the 3 samples (6.25%) from each type of three retail markets. L. monocytogenes was isolated in the 4 samples (8.3%) from department stores. The level of contamination of these foodborne bacteria was less than 100 CFU/g. The enterotoxin-encoding genes of S. aureus isolates were sea, seh, sei and sep gene. The gene similarity of L. monocytogenes isolated from two retail markets by Rep-PCR showed 57.8-98.1% and 68.1-98.1%, respectively. These results suggest that the HACCP guideline for environmental control in slaughterhouse and retail markets should be provided to prevent cross contamination and manage foodborne pathogens such as L. monocytogenes and S. aureus.

• Journal of radiological science and technology
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• v.33 no.1
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• pp.25-29
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• 2010

To evaluate the usefulness of newly designed percutaneous bone biopsy needle for pumpkin's specimen collection. We manufactured three types of biopsy needle with different internal processing which were made of 10 mm-diameter acrylic material. We made the conventional type (Ct) similar to the clinical type then compared the test group. The type a (Ta) made 1 cm-length internal processing from the distal, type b (Tb) made taper, and type c (Tc) made internal processing like spiral configuration. We performed 20 times biopsy to get an 10 mm length specimen from pumpkin's surface and evaluated the success rate of the biopsy, length of the specimen, and determine internal processing type of the most suitable biopsy needle (ANOVA test). Success rates of Ct, Ta, Tb, and Tc were 55%, 80%, 90%, and 100%, respectively. The lengths of the specimen of Ct, Ta, Tb, and Tc were $5.6{\pm}1.1\;mm$, $5.9{\pm}0.87\;mm$, $3.9{\pm}0.77\;mm$, and $9.4{\pm}0.54\;mm$, respectively. All groups were statistically significant (p < 0.05) except the group between Ct and Ta (p = 0.28). Newly designed bone biopsy needle seems to be useful for obtaining enough specimen. Tc may be more effective than other types.

• Korean Journal of Soil Science and Fertilizer
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• v.13 no.2
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• pp.57-63
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• 1980

The effect of particle size of silicate fertilizer, crushed slag from the steel industry, on the behavior of silicate in soil was investigated through laboratory experiments. The silicate fertilizer was sieved to obtain three fractions of particles, coarser than 10 mesh 20-35 mesh, and finer than 100 mesh. Silicate concentration of the extract obtained by shaking 20 mg of particles, coarser than 10 mesh, 20-35 mesh, and finer than 100 mesh, in 50 ml of distilled water for 4 hours was 0.3, 1.0, and 3.2 ppm respectively. As shaking the mixture of the silicate fertilizer and soil proceeded, silicate concentration of the extract increased, and this increase after 4 hour shaking was attributed mainly to dissolution of soil silicate. When the mixture of soil and the silicate fertilizer was incubated under submerged condition, silicate concentration of the solution decreased for the first 2-4 weeks, thereafter increased with incubation time. During this incubation period, silicate concentration of the solution changed inversely with pH of the solution. After 6-10 weeks, however, both silicate concentration and pH of the solution increased with incubation time. Silicate concentration of the effluent from the 14.5 cm soil column of which top 4.5 cm was packed with the mixture of 30 g of soil and 30 mg of the silicate fertilizer reached maximum at 0.94 pore volumes for the particles of 20-35 mesh and 1.03 pore volumes for the particles finer than 100 mesh, whereas the effluent concentration reached maximum at 0.88 pore volumes for the soil column without the silicate fertilizer treatment. Soil analysis made after water percolation revealed that 1.5 pore volumes of water could leach down large amount of the water soluble silicate but not the sodium acetate extractable silicate, from top 3-6 cm soil layer.

• Korean Journal of Veterinary Research
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• v.40 no.4
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• pp.653-660
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• 2000

In order to study the regional distribution and relative frequency of the immunoreactive endocrine cells in the gastrointestinal tract of the Mongolian gerbil, Meriones unguiculatus, the gastrointestinal tract was divided into 9 portions (cardia, fundus, pylorus, duodenum, jejunum, ileum, cecum, colon and rectum) and immunostained by immunohistochemical (PAP) method using 8 types of specific antisera against cholecystokinin (CCK)-8, gastrin, secretin, pancreatic polypeptide(PP), somatostatin, serotonin, glucagon and insulin. CCK-8-, gastrin-, somatostatin- and serotonin-immunoreactive cells were demonstrated in this study. These immunoreactive cells were found in the gastric gland regions of the pylorus or between parietal and chief cells of the fundus with round to spherical shaped, and in the interepithelial regions of the intestinal tract with spherical to spindle shaped except for jejunum where some of immunoreactive cells were also observed in the intestinal glands with round to spherical shaped. CCK-8-immunoreactive cells were restricted to the pylorus and duodenum with numerous and a few frequency, respectively. Gastrin-immunoreactive cells were restricted to the pylorus with numerous frequency. Similar to those of gastrin-immunoreactive cells, somatostatin-immunoreactive cells were restricted to pylorus with moderate frequency. Serotonin-immunoreactive cells were detected throughout whole gastrointestinal tract except for cardia and cecum with moderate or numerous frequency. However, no secretin-, PP-, glucagon- and insulin-immunoreactive cells were observed in this study. From these results, the appearance type, regional distribution and relative frequency of immunoreactive endocrine cells in the gastrointestinal tract of the Mongolian gerbils were somewhat lowered or restricted compared to those of other mammals and these differences were might be caused by feeding habits and species specification.

• Korean Journal of Animal Reproduction
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• v.25 no.2
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• pp.191-198
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• 2001

The purpose of this study was to investigate the effects of embryo sources such as in vivo vs. in vitro produced blastocyst, and culture systems on the membrane permeability and viability of bovine blastocyst following GMP vitrification. To produce in vivo embryos, six cows were superovulated by administration of follicle stimulation hormone (FSH) and prostaglandin $F_{2{\alpha}}$(PG $F_{2{\alpha}}$). in vitro embryos were produced by two different culture systems, oviduct co-culture (OCS) and defined culture system (HECM-6; DCS). Ovaries were picked up at a local slaughterhouse and transported to laboratory in 3$0^{\circ}C$ saline within 2 h. Ovaries were washed with same saline three times and then placed in saline on warm plate adjusted at 3$0^{\circ}C$ during aspiration. The blastocysts produced were assigned for membrane permeability and viability following GMP vitrification. The membrane permeability of blastocysts was checked in 0.5 M sucrose solution on warm plate at 35$^{\circ}C$ for 0, 2, 5 and 7 min, respectively. Then the diameters (width and length) of embryo cytoplasms were measured by a eyepiece meter, and they were converted to their volume by 4/3 $\pi$ $r^3$. The blastocysts were cryopreserved by GMP vitrification method, where they were sequentially placed into vitrification solution before being loaded into GMP vessels and immersed into L$N_2$ within 20 to 25 sec. Post-thaw blastocysts were serially washed in 0.25 and 0.15 M sucrose in HM and TCM-199 for 5 min each, and then cultured in TCM 199 supplemented with 10% FCS for 24 or 48 h. The volume change of in vivo blastocyst at 0, 2, 5 and 7 min (100, 37.1, 34.3 and 31.6%) was significantly more shrunk than those of in vitro blastocysts derived from OCS (100, 59.8, 48.9, 47.9%) and DCS (100, 57.2, 47.3 and 46.9%) (P＜0.05). The viability of post-thaw blastocyst derived from in vivo (93.6%) was also significantly different from those in OCS and DCS (81.9 and 83.6%; P＜0.05). In the present culture system, the morphology of embryos produced in vitro was similar to that of in vivo embryos, but the quality in membrane permeability and post-thaw viability showed a big difference from their sources as in vivo or in vitro derived from OCS and DCS. The results indicated that the quality of in vivo embryos in membrane permeability and post-thaw viability was better than those of in vitro embryos derived from OCS or DCS.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.1
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• pp.80-87
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• 2011

Panax ginseng has been used as a traditional medicine for several centuries in Korea. A laboratory experiment using methanol extracts of freeze-dried leaves and roots in the different ages of P. ginseng was conducted to determine the content of phenolics and flavonoids, antioxidant activity and cytotoxicity. The results indicate that the total phenolics level [mg ferulic acid equivalents (FAE) $kg^{-1}$ DW] was higher in leaves (22.0 to 76.3 mg $kg^{-1}$) than roots (19.0 to 28.3 mg $kg^{-1}$) of P. ginseng. The total content of phenolics in roots increased with increase in age of P. ginseng from one to six years. However, the content of phenolics in P. ginseng leaf decreased with the increase in age. Total flavonoid [mg naringin equivalents $kg^{-1}$ DW] was more detected in the leaves (30.3 to 138.6 mg $kg^{-1}$) than in the roots (0.0 to 10.6 mg $kg^{-1}$) of P. ginseng. The total flavonoid level in leaves decreased with increase in age of P. ginseng. The antioxidant potential of the methanol extracts from the plants dose-dependently increased. DPPH free radical scavenging activity was higher in leaves (36.9 to 82.8%) than in roots (14.8 to 39.4%), and in young plants than in old ones. According to 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the methanol extracts from 5 year-root part showed the highest cytotoxicity against Calu-6, followed by 2 year- and 3 year-roots. However, the methanol extracts from 6 year- and 4 year-roots had lower cytotoxicity. Total phenolics content in both leaves and roots was highly correlated with the DPPH radical scavenging ($r^2=0.7366$ to 0.7870) and nitrite scavenging ($r^2=0.5604$ to 0.8794) activities, suggesting that they contribute to the antioxidant properties of the P. ginseng plants.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.414-421
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• 2004

3D QSAR studies for protox inhibition activities against root and shoot of the rice plant (Orysa sativa L.) and barnyardgrass (Echinochloa crus-galli) by a series of new 1-(5-methyl-3-phenylisoxazolin-5-yl)methoxy-2-chloro-4-fluorobenzene derivatives were conducted based on the results (Sung, N. D. et al.'s, (2004) J. Korean Soc. Appl. Biol. Chem. 47(3), 351-356) using comparative molecular similarity indices analysis (CoMSIA) methodology. Four CoMSIA models, without hydrogen bond donor field for the protox inhibition activities against root and shoot of the two plants, were derived from the combination of several fields using steric field, hydrophobic field, hydrogen bond acceptor field, LUMO molecular orbital field, dipole moment (DM) and molar refractivity (MR) as additional descriptors. The predictabilities and fitness of CoMSIA models for protox inhibition activities against barnyard-grass were higher than that of rice plant. The statistical results of these models showed the best predictability of the protox inhibition activities against barnyard-grass based on the cross-validated value $r^2\;_{cv}\;(q^2=0.635{\sim}0.924)$, non cross-validated, conventional coefficient $r^2\;_{ncv.}$ value $(r^2=0.928{\sim}0.977)$ and PRESS value $(0.255{\sim}0.273)$. The protox inhibition activities exhibited a strong correlation with the steric $(5.4{\sim}15.7%)$ and hydrophobic $(68.0{\sim}84.3%)$ factors of the molecules. Particularly, the CoMSIA models indicated that the groups of increasing steric bulk at ortho-position on the C-phenyl ring will enhance the protox inhibition activities against barnyard-grass and subsequently increase the selectivity.