• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1625-1632
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• 2005

This study was conducted to monitor the extraction yields and functional properties from cabbage by a response surface methodology. The extract yield was maximized as 44.47$\%$ under the temperature of 79.86$^{\circ}C$, ethanol concentration of 56.84$\%$ and solvent to sample ratio 25.58 mL/g . The maximum value of electron donating ability was 85.46$\%$ at 46.38$^{\circ}C$,57.06$\%$ of ethanol concentration and 27.71 mL/g of solvent to sample ratio. The maximum value of tyrosinase inhibitory effect was 69.37$\%$ at 37.5$^{\circ}C$,47.71$\%$ of ethanol concentration and 16.03 mL/g of solvent to sample ratio. The maximum value of SOD-like activity was 48.36$\%$ in 66.12$^{\circ}C$, 70.35$\%$ of ethanol concentration and 29.13 mL/g of solvent to sample ratio. Estimated conditions for the maximized extraction including yield, electron donating ability and SOD-like activity were 20 $\∼$ 30 mL/g in ratio of solvent to sample, 25$\∼$85$\%$ in ethanol concentration, and 40$\∼$90$^{\circ}C$ in extraction temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.63-68
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• 1985

This study was conducted to investigate the dry matter production and distribution ratio of dry matter produced for each of 5 botanical types (Virginia-Small Seed, Virginia-Large Seed, Spanish, Valencia, Shinpung) of Peanut (Arachis hypogaea L.) in Peanut culture limiting region. The total dry weight increased in order of Virginia-Large seed, Virginia- Small Seed, Shinpung, Spanish, Valencia type. The maximum Crop growth rates (Cmax) were Virginia-Small seed 18.22-23.41 g/㎡/day, Virginia-Large seed 19.61-20.03 g/㎡/day, Shinpung 16.33-19.77 g/㎡/day, Spanish 13.86-16.28 g/㎡/day, Valencia 13.97-16.25g/㎡/day, respectively. LAI showed the high value at vinyl-mulching than non-mulching. In the early filling stage, distribution ratio of dry matter produced showed the highest at the shinpung type than the other types.

• The Korean Journal of Malacology
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• v.15 no.1
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• pp.31-39
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• 1999

This study was aimed to describe the population dynamics and secondary production of Tapes philppinarum on Chohwa and Toksan tidal flats in Kwangyang Bay, from June 1994 to July 1995. The size distributions in shell length showed bimodal patterns from June 1994 to April 1995. Thereafter the distribution changed to the passage of time, indicating an increase in shell length. The mean densities decreased gradually with month. Chohwa A sustained highestdensity, followed by Chohwa B, Toksan C, and Toksan D. The recruitment of new year class occurred first on the upper tidal flat, and then moved to the lower tidal flat. The mean biomass in flesh dry weight of each year class increased in spring just before the spawning period, and thereafter decreased progressively. Annual mean biomass wasrecorded as 170.7 g m$\^$-2/ at Chohwa A, 220.7 g m$\^$-2/ at Chohwa B, 21.8 g m$\^$-2/ at Toksan C, and 45.2 g m$\^$-2/ at toksan D. Annual productions of Ruditapes philippinarum were estimated as 259.72 g m$\^$-2/ yr$\_$-1/ at Chohwa A, 359.79 g m$\^$-2/ yr$\_$-1/ at Chohwa B, 45.02 g m$\^$-2/ yr$\_$-1/ at Toksan c, 68.88 g m$\^$-2/ yr$\_$-1/ at Toksan D. Annual productions were much higher on Chohwa tidal flat than those on Toksan tidal flat. While P:B ratio were higher on Toksan tidal flat as 1.70 than those on Chohwa tidal flat as 1.58. In conclusion, the Chohwa tidal flat showed higher biomass and producion of Ruditapes philippinarum, whereas the Toksan tidal flat showed higher P:B ratio. The total amount of potential food might influence on the density, biomass nad produciton, whereas the amount of food and space per individual might influence on the growth rate and P:B ratio.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.299-309
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• 2019

This study was designed to assess the quality and quantity of food resources such as the chlorophyll a concentration (Chl-a), the particulate organic carbon (POC) and the particulate organic nitrogen (PON), on blood cocke (Tegillarca granosa Linnaeus) farms from May to November 2017 in the northwestern area of Yeoja Bay, Korea. The values of Chl-a, POC and PON were $1.69-7.68{\mu}g{\cdot}L^{-1}$ (average: $3.48{\mu}g{\cdot}L^{-1}$ in the surface), 0.88-2.58 mM (average: 1.97 mM) and 0.17-0.90 mM (average: 0.54 mM), respectively, and these values were higher in the spring and summer and lower in the autumn. Furthermore, Chl-a and POC had higher values on the bottom layer than those vales on the surface, while PON had higher values on the surface than those values on the bottom. The POC/PON ratio and POC/Chl-a ratio were 1.56-7.88 (average: 3.71 on the surface of the water) and 216-967 (average: 700 on the bottom of the water), respectively, with most of the carbon sources being sediment-accumulated particle organic matter, and the contribution by phytoplankton was assessed as being low. These results show that the food source of the blood cockle farms in the northwest area of Yeoja Bay seems to be abundant in quantity, but this is considered to be very poor in quality.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.190-195
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• 2005

The conditions for the extraction of effective substances from the stem of Opuntia ficus-indica were optimized by a response surface methodology. The total extract yield was maximized under the temperature of $97.77^{\circ}C$, at a time duration of 145.82 min and a water to sample ratio 16.59 mL/g. Moreover, the optimum conditions for the extraction of effective substances were as follows: $84.95^{\circ}C$, 156.50 min and a water/sample ratio of 7.46 mL/g for the phenolics content; and $97.11^{\circ}C$, 139.03 min and a water/sample ratio of 10.91 mL/g for the pectin content. The range of optimum extraction conditions in consideration of the physicochemical properties of the extracts were shown to be as $95-100^{\circ}C$ as the extraction temperature, 120-180 min as extraction time and a water to sample ratio of 5-18 mL/g.

• Food Science and Preservation
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• v.15 no.1
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• pp.111-117
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• 2008

As part of studies on functional food development from the acorn (Quercus acutissima CARRUTHERS), this study investigated the antioxidant properties of the acorn using response surface methodology. Optimal extraction conditions were established by monitoring total phenol levels, electron donating ability, antioxidant ability and nitrite-scavenging action using response surface analysis under a central composite design. The extraction temperature varied in the $30-70^{\circ}C$, the extraction time between 1-5 h, and the solvent ratio was in the interval 5-25mL/g of sample. Extracted total phenols were highest at $57.91^{\circ}C$, 4.08 h, and 22.39 mL/g. This extraction was influenced by solvent ratio, but not by extraction time or temperature. Electron donating ability was found to be highest at $60.37^{\circ}C$, 2.85h, and 6.47 mL/g. The highest antioxidant level was 2.09 AI at $37.11^{\circ}C$, 1.67 h, and 18.84 mL/g, and this value was greatly influenced by all of extraction temperature, extraction time, and solvent ratio. Nitrite-scavenging ability was found to be highest at $47.07^{\circ}C$, 1.24h, and 19.55mL/g. Changes in nitrite-scavenging ability were most influenced by solvent ratio, followed by extraction temperature, but no influence of extraction time within the range tested was found.

• International Journal of Oral Biology
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• v.40 no.4
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• pp.175-182
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• 2015

Previous studies suggested that myelinated axons innervating rat molar pulps undergo morphological changes in their peripheral course. However, little information is available on the morphological feature of the parent axons at the site of origin. We therefore investigated the size of the myelinated parent axons and their morphological features at the proximal sensory root of the trigeminal ganglion by horseradish peroxidase (HRP) injection into rat upper molar pulps and subsequent light and electron microscopy. A total of 248 HRP-labeled myelinated axons investigated were highly variable in the size. Fiber area, fiber diameter, axon area (axoplasm area), axon diameter (axoplasm diameter), and myelin thickness were $11.32{\pm}8.36{\mu}m^2(0.80{\sim}53.17{\mu}m^2)$, $3.99{\pm}1.53{\mu}m(1.08{\sim}9.26{\mu}m)$, $8.70{\pm}6.30{\mu}m^2(0.70{\sim}41.83{\mu}m^2)$, $3.13{\pm}1.13{\mu}m(0.94{\sim}7.20{\mu}m)$ and $0.43{\pm}0.23{\mu}m(0.07{\sim}1.06{\mu}m)$, respectively. The g-ratio (axon diameter / fiber diameter) of the labeled axons was $0.79{\pm}0.05$ (0.61~0.91). Axon diameter was highly correlated with myelin thickness (correlation coefficients, r=0.83) but little correlated with g-ratio (r=-0.33) of individual myelinated parent axons. These results indicate that myelin thickness of the myelinated parent axons innervating rat molar pulps increase with increasing axon diameter, thus maintaining a constant g-ratio.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.3
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• pp.178-189
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• 2008

The distribution of inorganic nutrients and their remineralization ratio in the divergence zone ($7^{\circ}{\sim}10.5^{\circ}N$) of the northeastern Pacific were investigated from July 2003 to July 2007. A divergence zone along the boundary of the North Equatorial Counter Current (NECC) and North Equatorial Current (NEC) at $10^{\circ}N$ was observed in July 2007 when the La Nina event and divergence-related upwelling was strong. The mean depth of oligotrophic surface mixed layer in the divergence zone was 46, 61, and 30 m in July 2003, August 2005, and July 2007, respectively. Below the surface mixed layer, a nutricline was clearly observed. The depth integrated value of nitrate including nitrite (DIVn) in the upper layer($0{\sim}100$ m depth) ranged from 5.51 to 21.71 $gN/m^2$(mean 12.82 $gN/m^2$) in July 2003, from 5.62 to 8.46 $gN/m^2$ (mean 7.15 $gN/m^2$) in August 2005, and from 8.98 to 27.80 $gN/m^2$(mean 21.12 $gN/m^2$) in July 2007. The maximum DIVn was observed at the divergence zone. The distributions of phosphate(DIVp) and silicate(DIVsi) were similar to that of DIVn and the DIVn/DIVsi ratio was $0.87{\pm}0.11$ in the upper layer. The limiting nutrient for phytoplankton growth in the study area was identified as nitrogen(N/P ratio=14.6). The nitrate (including nitrite) concentrations were lower in the region mainly affected by NEC than in the region affected by NECC. The study area of low silicate concentrations was also considered to be Si-limiting environment. The remineralization ratios of nutrients were $P/N/-O_2=1/14.6{\pm}1.1/100.4{\pm}8.8(23.44{\leq}Sigma-{\theta}{\leq}26.38)$ in the study area. These ratios suggested remineralization process in the surface layer of divergence zone.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.4
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• pp.279-286
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• 2018

The objective of this study was to quantitatively evaluate the influence of the netting hanging ratio on fishing performance of gillnet. A total of six tests was carried out using three kinds of gillnets with different horizontal hanging ratios (0.3, 0.5 and 0.7) on the basis commercial gillnet of mesh size of 60 mm used in Yeosu Dolsan. As a result of the test fishing operation, catches of the net with hanging ratio 0.3 and the shortest float length was 1.34 times larger than the net with hanging ratio 0.7. The caught species in experimental testes was lager in the net with hanging ratio 0.3 than the net with hanging ratio 0.7. The catch rate per unit area (CPUE) is on the silver croaker with the largest catches in tests as follows. The net with hanging ratio 0.3 net was $89.45g/m^2$, hanging ratio 0.5 net was $41.63g/m^2$, and hanging ratio 0.7 net was $24.50g/m^2$. The net with hanging ratio 0.3 (float line length of 45 m) exhibited the largest CPUE value.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.117-122
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• 2005

Beijerinckia indica was cultured in mineral salts medium (MSM) medium with various carbon and nitrogen sources to improve the production yield of heteropolysaccharide-7 (PS-7). At high C/N ratio, the high concentration of PS-7 was produced until 40 h of the culture, whereas most of the glucose as a carbon source was used for the cell growth at low C/N ratio. However, at the high C/N ratio, PS-7 accumulation stopped at 48 h of the culture due to the increasing viscosity of the culture broth would inhibit the cell growth. Therefore, the optimized value of C/N ratio was 33.3 (20 g/L glucose, 7.5 mM $NH_{4}NO_3$) for the high production of PS-7. In the culture with various carbon sources, B. indica effectively used the hexoses or glucose-generating sugars for PS-7 formation. Especially, sucrose was the best carbon source for the high production of PS-7 (6.96 g/L) with a high viscosity (40772 cp). In the culture of B. indica with MSM medium containing 20 g/L glucose and 7.5 mM $NH_{4}NO_3$ in a 51 fermentor, the highest cell concentration was 2.5 g/L and the highest concentration of PS-7 was 7.5 g/L (35174 cp). The additional nitrogen sources of 7.5 mM $NH_{4}NO_3$, glutamine and glutamate at 12 h of the culture after exhaustion of a nitrogen source regulated the metabolism of carbon sources, therefore the nitrogen sources could control PS-7 synthesis.