• Korean Journal of Plant Resources
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• v.37 no.2
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• pp.110-119
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• 2024

This study was conducted to provide information on the possibility of using Rhododendron micranthum as resource plant. Through polyphenol profiling of R. micranthum shoot extract, useful components were selected and the content of useful components and antioxidant activity by extraction solvent were compared. As a result, 37 polyphenol compounds were identified in R. micranthum shoot extract through LC-ESI-MS analysis. Contents by extraction solvent were compared of chlorogenic acid, astragalin, myricetin, and afzelin. Chlorogenic acid was highest at 6.57±0.12 mg/g in the ethanol extract, astragalin was 2.29±0.02 mg/g in the ethanol extract, myricetin was 4.77±0.06 and 4.52±0.27 mg/g in the methanol, ethanol extracts, and afzelin was highest at 0.10±0.01 mg/g in the methanol extract. Total polyphenol content of the R. micranthum shoot extract according to the extraction solvent was highest in the ethanol extract at 80.01±2.36 mg/g, and total flavonoid content was also highest in the ethanol extract at 78.08±3.44 mg/g. The IC₅₀ value of DPPH radical scavenging activity according to the extraction solvent of R. micranthum shoot was lowest in methanol extract at 943.57±10.68 mg/L, and the IC₅₀ value of ABTS radical scavenging activity was also lowest in methanol extract at 641.60±7.58 mg/L.

• Communications of the Korean Mathematical Society
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• v.12 no.3
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• pp.717-723
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• 1997

The compact transformation group has been developed with lots of properties. Many properties which are satisfied on G-space for compact group G do not hold for noncompact case. To recover some theory on spaces with noncompact group action we give some restriction on G-spaces. Hence we introduced Cartan G-spaces and proper G-spaces for our goal and we prove some properties on these G-spaces with noncompact G.

• Food Science and Preservation
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• v.23 no.5
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• pp.738-745
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• 2016

We evaluated the distribution pattern of tannin in 164 sorghum breeding lines and the inhibition rates of amylase, protease, and lipase in sorghum lines with different tannin concentrations. Tannin was existed in the testa of sorghum grain. The tannin content in whole grain of Nampungchal sorghum was 11.54 mg/g, and that in grain (milling rate 73%) and bran fractions was 4.57 mg/g and 28.71 mg/g, respectively. The inhibition rate of ${\alpha}$-amylase, ${\alpha}$-glucosidase, and ${\beta}$-glucosidase in sorghum lines with tannin was higher than that in sorghum lines without tannin. The inhibition rate of ${\alpha}$-glucosidase was greater than 97% in sorghum lines with tannin. The inhibition rate of protease ranged from 20% to 70% in the sorghum lines, showing no discernable trends in tannin content. Lipase inhibition was either very low or not observed and did not seem to correlate with tannin concentration.

• Solar Energy
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• v.14 no.2
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• pp.51-60
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• 1994

The fluidization characteristics of the furan foundry sand fluidized bed and the heat transfer characteristics on a single spiral coil tube in the bed have been investigated. In the paper, the heat transfer coefficients for a single spiral coil tube are measured in the furan foundry sand bed as a function of the ratio of heated coil tube pitch to diameter(p/Do) and the ratio of heated coil tube pitch to particle size(p/dp). The experimental results are as follows. 1) Mean heat transfer coefficients increases according to the increasing ratio of heated coil tube pitch to diameter(p/Do). 2) The Increasing rates of mean Nusselt numbers are more greater in the case of p/Do=1.58 than p/Do=4.75. 3) Mean Nusselt number can be expressed by the following equation, $Nu_{mean}=C\;Re^m\;Pr_g^{0.4}(p/dp)^n$.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.297-304
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• 2002

This study was conducted to investigate the influence of dietary Panax Ginseng Refuse(PGR), Dioscorea Japonica Refuse(DJR) and Oriental Medicine Refuse(OMR) on performance(feed intake, body weight gain, feed conversion, mortality) of Korean Native Chicken(KNC). KNC were randomly assigned to one of the 4 dietary treatment : 1) control(commercial feed), 2) PGR(commercial feed supplemented with 5% panax ginseng leaves) 3) DJR(commercial feed with 5% dioscorea japonica hulls and 4) OMR (commercial feed with 5% oriental medicine refuse). 160 KNC were fed one of the above experimental diet for 12 weeks and slaughtered at 20 weeks of age. Daily DM intake of control, PGR, DJR and OMR diet were 125.79g, 122.26g, 122.30g and 123.72g, respectively, with no significantly difference(p$>$0.05). The DM utilizability of control and DJR(62.89% and 61.20%) diets were higher(p$<$0.05) than those of PGR and OMR(55.44% and 59.76%)(p$<$0.05). 16 weeks weight of bird fed control, PGR, DJR and OMR diets were 1,436.6g, 1,427.2g, 1,546g and 1,422.0g respectively with DJR being the highest than other treatments(p$<$0.05). Total feed intake of control, PGR, DJR and OMR diets were 6,087g, 5,947g, 5,816g and 5,852g, respectively where control was higher than other treatments. The feed conversion of PGR, DJR and OMR were higher than the control. Chicken housed mortality of control, PGR, DJR and OMR were respectively 24, 15, 13 and 20 birds with rather lower mortality in the supplented groups(p$<$0.05). The body weight, carcass weight and carcass yield were not different among the treatments. But abdominal fat of chicken in control and OMR groups were higher than that of DJR and PGR groups.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.473-477
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• 2004

Wasabis (Wasabia japonica Matsum.) have been used as a spice with its petioles and rhizomes, but the production of its rhizomes in upland cultivation was very difficult for the severe damage of rotting disease during summer season. This experiment was carried out to increase the yield of marketable rhizome in wasabi when cultured in upland. Seedlings were raised in sub-alpine area for 7 and 12 months and then transplanted to experimental area on Sept. 20 and the yield was investigated on May 12 of the next year. The marketable rhizome(above 40g/plant) was produced in seedlings raised for 7 months. Production rate of marketable rhizome was 13.3% and total yield was 72.9 kg/10a. The content of allylisothiocyanate in rhizome of upland wasabi was 0.777 mg/g and its content was equal to wasabi cultured in water condition for 18 months. These results suggested that the upland cultivation of wasabi seedlings raised in sub-alpine area for 7 months was possible to product marketable rhizome.

• Food Science and Preservation
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• v.11 no.4
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• pp.503-507
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• 2004

The quality of bread made of sprouted brown rice ($20\%$), wheat flour and pumpkin powder was investigated. The bread was manufactured with 0, 1, 3 and $5\%$ pumpkin powder (W/W) with increasing and wheat flour. Volume of the breads were decreased from 4.68 mL/g to 3.60 mL/g as pumpkin powder contents increased from $0\%\;to\;5\%$. Lightness decreased with increasing pumpkin powder contents. Yellowness increased from 10.97 to 27.01 with increasing pumpkin powder contents. Textural characteristics of bread crumb were influenced by adding additives pumpkin powder. Hardness, adhesiveness and chewiness of bread decreased as the added level of pumpkin powder. In sensory evaluation, sensory scores for color, flavor and overall quality of bread increased with increasing pumpkin powder contents.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.706-713
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• 2013

With pot-grown 4-year-old 'Fuyu' persimmon trees, this study evaluated the effect of different nitrogen (N) rates during summer on fruit characteristics, changes of leaf nutrients after harvest, reserve accumulation, and early growth the following year. A total of 0, 36 g N in June, and 72 g N in June and July was fertigated to each tree using urea solution. All the fruits were harvested on Nov. 3. Although not significant, fruits were larger for the 36 g and 72 g N than the 0 g N. Fruits for the 0 g N, having lower N concentration, were softer and had a better coloration and higher soluble solids, indicating that they matured earlier. SPAD value on Nov. 3 was 19.2 for the 0 g N and 54.9 for the 72 g N, and then the values linearly decreased in all the treatments by Nov. 14, exhibiting rapid leaf senescence. Specific leaf weight, being the lowest for the 0 g N, also gradually decreased during this period. Increasing N level significantly increased cross-sectional area of the trunk. Leaf N concentration on Nov. 3 was 0.87% for the 0 g N, whereas it was 1.18 and 1.52% for the 36 g and 72 g N, respectively. The N fertigation tended to increase leaf concentrations of soluble sugars, starch, and amino acids. Contents of N, P, K, soluble sugars, starch, and amino acids per unit leaf area gradually decreased in all the treatments during the 11 days after harvest, and the extent of the decrease was the lowest for the 0 g N. On the other hand, those of Ca, Mg, and protein did not consistently change during this period. The N fertigation resulted in higher concentrations of N in dormant shoots on Nov. 14, and although not great, it also increased soluble sugars, starch, amino acids, and protein. Clear differences were found in number of flower buds per one-year-old branch and total shoot length per tree the following year. The 72 g N trees had 5.6-fold more flower buds and 1.9-fold more shoot length, compared with those of 0 g N trees. However, it was noted that tree growth the following year was not significantly different between the 36 g and 72 g N the previous year. It was concluded that N rate during summer should be adjusted with considering the changes of fruit maturation, mobilization of leaf nutrients, and reserve accumulation.

• Parasites, Hosts and Diseases
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• v.48 no.1
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• pp.81-83
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• 2010

To figure out the geographical distribution of Gynaecotyla squatarolae and Microphallus koreana metacercariae in Korea, shore crabs of southwestern coastal areas were examined. Eight coastal areas in Inchon-si (A), Gyeonggi-do (B), Chungcheongnam-do (C, D, and E), Jeollabuk-do (F), and Jeollanam-do (G and H) were selected, and 2 kinds of crabs, Macrophthalmus dilatatus and/or Macrophthalmus japonicus, were caught. After transportation to the laboratory, 15 crabs per each group were grouped and ground in a mortar and pestle, and examined for microphallid metacercariae. In M. dilatatus, G. squatarolae metacercariae were recovered from 3 (C, E, and H) out of 6 regions, but M. koreana metacercariae were not recovered. In the case of M. japonicus, G. squatarolae metacercariae were recovered from 6 (B, D, E, F, G, and H) of 7 areas surveyed, and M. koreana matacercariae were detected from 5 regions (A, B, D, F, and H). These results indicate that the life cycle of G. squatarolae is maintained in the western coastal areas using M. dilatatus and M. japonicus as intermediate hosts, while that of M. koreana is maintained only using M. japonicus.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.502-506
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• 2005

Three EGCG analogues were synthesized by the acceptor reaction of a glucansucrase from Leuconostoc mesenteroides B-1299CB with EGCG and sucrose. The transfer products was purified using Sephadex LG-20 column chromatography and high performance liquid chromatography (HPLC). EGCG-G1 and EGCG-G2 were novel compounds for the first time reported in this paper. EGCG glycosides showed similar or slower antioxidative effects according to their structures $(EGCG{\geq}EGCG-G1>EGCG-G1'>EGCG-G2)$. However, the water solubilities of the EGCG-G1, EGCG-G1' and EGCG-G2 were 52, 76 and 140 times higher than that of EGCG. Furthermore, they showed more browning resistance against UV irradiation than EGCG.