• Microbiology and Biotechnology Letters
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• 제25권1호
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• pp.68-74
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• 1997

The conversion of D-sorbitol to L-sorbose by Gluconobater suboxydans was analyzed, and continuous production of L-sorbose was carried out in immobilized cell reactors. L-Sorbose production by high densities of resting cells was more effective than by conventional batch fermentations. Sorbitol dehydrogenase, an enzyme converting D-sorbitol to L-sorbose, did not suffer from substrate inhibition, but from product inhibition. When L-sorbose production was carried out with Ca-alginate-immobilized cells, about 60 g/l of L-sorbose was obtained. On the other hand, when the corn steep liquor (CSL) concentration of medium was reduced to 0.08%, 80 g/l of L-sorbose was obtained. Outgrowth inside the immobilized carriers was thought to block the pores of the carriers so that substrate could not easily diffuse through the carriers. Continuous production of L-sorbose was well accomplished in a bubble column reactor, and 6. 5 g/l.h of productivity and 81.2% of yield were obtained at a substrate feeding rate of 0.08h$^{-1}$ under the optimum conditions with carrier volume of 55% and aeration rate of 3 vvm.

• Magazine of the Korean Society of Agricultural Engineers
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• 제42권3호
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• pp.45-55
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• 2000

This study was carried out to derive optimal design low flows bythe Weibull-3 and Wakeby distributions for the partial consecutive duration series at seven watersheds along Han. nagdong, Geum Yeongsan and Seomjin river systems. L-coefficient of variation L-skewness and L-kurtosis were calculated by the L-moment ratio respectively. Parameters were estimated by the method of L-Moments with consecutive duration. Design low flows obtained by method of L-Moments using with consecutive duration, Design low flows obtained by method of L-Moments using different methods for plotting positions formulas in the Weibull-3 and Wakeby distributions were compared by the Root Mean Square Errors(RMSE). It has shown that design low flows derived by the method of L-moments using Weivull plotting position formula in Wakeby distribution were much closer to those of the observed data in comparison with those obtained by the methods of L-moments with the different formulas for plotting positions in Weibull-3 distribution from the viewpoint of Root Mean Square Errors.

• Journal of Applied Biological Chemistry
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• 제55권4호
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• pp.207-215
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• 2012

Phenolic compounds of $17.9{\pm}1.0mg/g$ were extracted from Ulmus pumila with 70% ethanol. The elastase inhibitory activity related with forming wrinkle was shown an excellent wrinkle improvement effect in 70% ethanol extracts as 55.5-69.5% at phenolic concentration of $50-200{\mu}g/mL$. The tyrosinase inhibitory activity related with skin-whitening was 24% in 70% ethanol extracts at phenolic concentration of $200{\mu}g/mL$. The astringent activity of 70% ethanol extracts was shown activity of 71% at phenolic concentration of $200{\mu}g/mL$ therefore it is judged that there is a high effect on pores reduction of the skin. The hyaluronidase inhibitory activity of U. pumila extracts was confirmed anti-inflammation effect of 80% at phenolic concentration of $50{\mu}g/mL$. Antimicrobial activity of U. pumila water extracts was shown each 8.7, 10.0, 11.1 and 11.8 mm clear zones on Propionebacterium acnes at phenolic concentration of $50-200{\mu}g/mL$. The stability of the multi-functional cosmetic (lotion) added U. pumila extracts was very stable for 28 days without changing of pH and viscosity also it's stable on temperature and sun lights. As the concentration of extracts was increased, the color of lotion was getting dark, but the sensory evaluation was high at score of 8.5.

• Journal of Aquaculture
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• 제13권2호
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• pp.119-128
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• 2000

Exposure to air and increased temperature induced successful spawning in Mytilus edulis, M. coruscus Crassostrea gigas and Pinctata fucata martensii. Developmental durations required for an egg to attain D-shaped larva and the D-shaped larva to reach pediveliger stage were estimated in these bivalves. Size of fertilized eggs was the largest (70.3 ${\mu}m$) in M. coruscus and the smallest (45.3 ${\mu}m$) in P. fucata martensii. At 17$^{\circ}C$, M. edulis and M. coruscus attained D-shaped larval stage within 48 hours after fertilization but those of C. gigas and B. fucata martensiii within 24 and 22 hours at 21 and 26$^{\circ}C$, respectively. The development duration required for a D-shaped larva to attain pediveliger stage was the longest (27 days) in M. coruscus and ranged between 20 and 22 days for the others. The shell length of the pediveliger was the longest (274.9 ${\mu}m$) in C. gigas and smallest (190.9 ${\mu}m$) in P. fucata martensii Length and height of larval shell was highly correlated with each other in all the 4 species. The shell height of C. gigas was more than the shell length beyond the size of 100 ${\mu}m$ shell length. However, shell length of the others was always longer than shell height at the larval stage.

• Korean Journal of Food Science and Technology
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• 제31권6호
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• pp.1415-1420
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• 1999

This study was carried out to obtain basic information for breeding materials on the improvement of waxy corn (Zea mays L.). The percents of palmitic, stearic, oleic, linoleic and unsaturated fatty acids in 310 $F_1's$ analyzed were $14.6\;{\pm}\;2.5%,\;2.5\;{\pm}\;1.0%,\;24.8\;{\pm}\;4.2%,\;55.6\;{\pm}\;5.4%\;and\;81.8\;{\pm}\;3.1%$, respectively. The mean value of antioxidative ability was $22.8\;{\pm}\;5.9%$. The average contents of tocopherols, phenolic compounds and carotenoids were $36.2\;{\pm}\;11.5\;{\mu}g/mL,\;120.3\;{\pm}\;27.7\;{\mu}g/mL\;and\;0.4\;{\pm}\;0.6\;{\mu}g/mL$, respectively. The level of oleic acid was significantly correlated with the level of linoleic acid. The electron donating ability was significantly correlated with the level of phenolic compounds and tocopherols but not with the content of carotenoids

• Korean Journal of Plant Resources
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• 제23권5호
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• pp.458-464
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• 2010

Twelve garlic cultivars collected from Korea and Mongolia were evaluated genetic similarity and diversity by RAPD method using oligo-nucleotide random primers. Genomic DNA isolated from twelve garlic cultivars were amplified by polymerase chain reaction using 143 primers, and 55 primers showed polymorphic DNA bands. Among a total of 187 bands amplified by 55 primers, 128 polymorphic bands were subjected to analysis for genetic relationship of garlic cultivars. Garlic cultivars were classified into three groups, such as group-I corresponded to Euiseong, Seosan, Samchuk and Yecheon-A, Yechun-B, Euiseong-norang, Jeongsun, Namdo, Yookback and Danyang cultivars, and group-II to Mongolia and group-III to Daeseo cultivars. Thirty DNA bands showing unique specificity to the specific cultivars are likely to be useful for identification of garlic local cultivars as DNA markers.

• Applied Chemistry for Engineering
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• 제27권3호
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• pp.276-279
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• 2016

In this study, we extracted active components from thistle, persimmon leaf, and new green which are known to have a high content of antioxidants and also analyzed the 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavening activity and flavonoid content. Both ultrapure water and alcohol were used as extraction solvents and the ratio of both solvents, sample, amunts extraction time, and extraction temperature were varied. The optimal extraction condition of each natural compounds were 2.5~3.5 h of the extraction time and 50 g/L of the sample amount. The optimal ratio of ultrapure water and alcohol and extraction temperature were as follows; persimmon leaf (55~65 vol%, $50{\sim}60^{\circ}C$), thistle (40~50 vol%, $55{\sim}65^{\circ}C$) and new green (55~65 vol%, $50{\sim}60^{\circ}C$). In addition, the antioxidant capacity and flavonoid content of the extract increased in the order of persimmon leaf, thistle, and new green.

• Journal of the Korean Institute of Telematics and Electronics D
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• 제34D권3호
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• pp.60-73
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• 1997

By introducing a compressive-strained quanternary InGaAsP quantum-wells instead of a conventional ternary InGaAs quantum-wells in 1.55.mu.m DFB-LD, the lasing performances canb e improved and the problems caused by the thickness non-uniformity and the compositional abruptness among the hetero-interpaces canb e relaxed. In this paper, we investigated an iptimum InGaAsP/InGaAsP multiple-quantum-well(MQW) structure as an active layer in a direct-modulated 1.55.mu. DFB-LD from the view point of threshold current, chirping charcteristics, and resonance frequency. The optimum compressive-strained MQW structure was revealed as InGaAsP/InGaAsP structure with strain amount of about 1.2%, number of wells $N_{w}$ of 7, well width $L_{w}$ of 58.agns.. The threshold current density J of 500A/c $m^{2}$, the linewidth enhancement factor a of 1.8, and differential resonance frequency of d $f_{r}$/d(I-I)$^{1}$2/=2GHz/(mA)$^{1}$2/(atI=2 $I_{th}$) were expected in 1.55.mu.m .gamma./4-shifted DFB-LD with the cavity length of 400.mu.m long and kL value of 1.25. These values are considerably improved ones compared to those of 1.55um DFB-LD with InGaAs/InGaAsP MQW which have enhancement factor and the resonance frequence frequency by the detuning of lasing wavelength and gain-peak wavelength. It was found that the linewidth enhancement factor of 20% and differential resonance frequency of 35% without the degradation of the threshold current density could be enhanced in the range of -15nm~-20nm detuning which can be realized by controlling the thickness and Incomposition of InGaAsP well. well.and Incomposition of InGaAsP well. well.

• Proceedings of the Korean Society of Crop Science Conference
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• 한국작물학회 1994년도 춘계 학술대회지
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• pp.54-55
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• 1994

• Proceedings of the Korean Environmental Sciences Society Conference
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• 한국환경과학회 1997년도 정기총회 및 봄 학술발표회 초록집
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• pp.55-57
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• 1997