• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.124-128
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• 2003

In order to isolate and characterize a novel fungal strain capable of producing cellulase, each samples of the old rice straw, soil, and the old tree were screened by congo red test. One of the fungi screened has been identified as Aspergillus tubingensis strain from the results of the phylogenic analysis based on partial DNA sequence and the basis of its biochemical properties. A carboxymethyl cellulase activity of the strain was higher than that of A. oryzae KCTC 6291. In CMCase activity measurement, it wasn't sensitive about pH 2.0, 3.0, 4.0, but the enzyme was more stable than A. oryzae under the various pH and temperature conditions and the enzyme activity was more similar to neutrality and alkali. Therefore, it could be suggested that the isolated strain has a potential possibility for the developing of the probiotics.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.230-237
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• 1989

This research was carried out to investigate the influences of temperature and light on the herbicidal activity of oxyfluorfen, oxadiazon and paraquat. Increased temperature from 10 to $35^{\circ}C$ resulted in increase of herbicidal activity in whole plants or leaf discs treated with herbicides. It seemed that temperature affected herbicide penetration into and reaction to the action site rather than appearance process of herbicidal activity (maybe membrane peroxidation after being absorbed. The activity of compounds tested increased with increased light intensity. Paraquat showed similar activities regardless of light qualities but oxyfluorfen and oxadiazon showed the highest activities in blue light spectrum, indicating that they seemed to be closely related to chlorophyll biosynthesis rather than carotenoid biosynthesis or electron transport systems of photosynthesis and respiration.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.116.2-116.2
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• 2017

DLC (Diamond like carbon) 박막을 전극 재료로 활용하기 위해서는 높은 전기 저항과 금속성 기판에 대한 낮은 접착력을 극복해야 한다. 본 연구에서는 PECVD에 의해 합성 된 DLC/Ti 전극의 아크 중간층, 질소 도핑, 증착 및 열처리 온도가 접착 강도와 전기적 및 전기 화학적 특성에 주는 영향을 체계적으로 조사 하였다. 그 결과, arc ion plating (AIP) 법에 의해 증착 된 Ti/TiC 중간층의 도입은 스크래치 테스트와 전기화학적 싸이클 테스트에서 향상된 접착 강도 및 수명을 가져온다는 것을 확인 하였다. 그리고 arc 중간층에서의 arc droplet은 DLC 박막의 표면적을 넓혀 전기 화학적 활성도를 높이는 긍정적인 역할을 하였다. 소량의 질소 도핑은 DLC 막의 비저항을 크게 낮춰주었고, 전기화학적 활성도를 증가시켰다. 증착 온도가 높을수록 DLC 막의 sp2/sp3 비율이 증가하였고, 이에 따라 비저항은 감소하였으며 전기 화학적 활성도는 증가하였다. 반면, 가장 높은 전기화학적 전위창은 $300^{\circ}C$ 에서 얻어졌으며 더 높은 온도에서 감소하였다. 열처리 온도를 높일수록 비저항의 감소 및 전기 화학적 활성도가 증가한 반면, 전기화학적 전위창은 지속적으로 감소하였고, 높은 열처리 온도에서는 DLC 전극의 수명이 줄어드는 것을 확인 하였다.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.59-67
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• 2018

This study was conducted to isolate the cellulolytic bacteria able to grow on LB- Carboxymethyl cellulose (CMC) agar trypan blue medium from the mixed forest and Larix leptolepis stands. Three bacterial strains with high activity against both CMC and xylan were isolated. Both API kit test and 16S rRNA gene sequence analysis revealed that the three different isolates belong to the gene Bacillus. Therefore, the isolates named as Bacillus sp. EFL1, Bacillus sp. EFL2, and Bacillus sp. EFP3. The optimum growth temperature of Bacillus sp. EFL1, EFL2, and EFP3 were $37^{\circ}C$. The optimum temperature for CMCase and xylanase from Bacillus sp. EFL1 were $50^{\circ}C$. The optimum pH of Bacillus sp. EFL1 xylanase was pH 5.0 but the optimum pH of CMCase from Bacillus sp. EFL1 was pH 6.0. The optimum temperature of CMCase and xylanase from Bacillus sp. EFL2 was $60^{\circ}C$, respectively. The optimum pH of CMCase of Bacillus sp. EFL2 was 5.0, whereas xylanase showed high activity at pH 3.0-9.0. The optimum temperature for CMCase and xylanase of Bacillus sp. EFP3 was $50^{\circ}C$. The optimum pH for CMCase and xylanse was 5.0 and 4.0, respectively. CMCases from Bacillus sp. EFL1, EFL2, and EFP3 were thermally unstable. Although xylanase from Bacillus sp. EFL1 and EFP3 showed to be thermally unstable, xylanase from Bacillus sp. EFL2 showed to be thermally stable. Therefore, Bacillus sp. EFL2 has great potential for animal feed, biofuels, and food industry applications.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.525-532
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• 1995

The periods of germination and seedling emergence, epidermal cell size and the activities of peroxidase and amylase of 6 rice cultivars were examined to clarify the response to 3 temperature conditions, constant temperatures of 27$^{\circ}C$ and 17$^{\circ}C$ and alternating temperature of 24/1$0^{\circ}C$, in the dark condition. The periods of germination and seedling emergence were increased and the germination was delayed greater than the seedling emergence under 17$^{\circ}C$ and 24/l$0^{\circ}C$, compared with 27$^{\circ}C$. Lengths of epidermal cell of coleoptile and first leaf were reduced, but the widths were increased in the 17$^{\circ}C$ and 24/1$0^{\circ}C$, compared with 27$^{\circ}C$. The activities of peroxidase in the emerging shoots and amylase in the germinating seeds were reduced in 17$^{\circ}C$ and 24/1$0^{\circ}C$. There were significant correlations between peroxidase activities and the widths of epidemal cell of first leaf and between amylase activities and periods of germination. Varietal differences of all observations were remarkable in 17$^{\circ}C$ and 24 /1$0^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.7-12
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• 1994

The kinetics of browning reaction of dried shrimp powder samples were investigated during storage. The temperature conditions of the ding process were $25^{\circ}C\;and\;45^{\circ}C$, and the samples were stored at water activity ($a_w$) of 0.33, 0.44, 0.52, 0.65 and temperatures of $35^{\circ}C,\;45^{\circ}C,\;55^{\circ}C$ and temperature fluctuations between $33^{\circ}C\;and\;55^{\circ}C$. When the shrimp was dried at $25^{\circ}C$ the activation energies obtained from the Arrhenius plot ranged from 13.57 to 14.33 kcal/mol. From these energies of activation, the $Q_{10}$ values at $25^{\circ}C$ showed 1.93 to 2.00. In the case of drying at $45^{\circ}C$ the activation energies were $13.12{\sim}13.61\;kcal/mol$ and $Q_{10}$ values were $1.89{\sim}1.93$, respectively. In addition, a storage study under square-wave fluctuating temperature conditions was carried out by varying the shrimp sample temperature between $35^{\circ}C\;and\;55^{\circ}C$ within 7 days regular fluctuation cycle. The data obtained from the fluctuating temperature storage study will be used in the prediction of shelf-lives. The shelf-lives assessed at $25^{\circ}C$ from the accelerated shelf-life tests ranged from 4 days at aw 0.65 to 139 days at aw 0.33.

• Fire Science and Engineering
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• v.12 no.1
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• pp.9-14
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• 1998

The hepatfluoropropane(HFC-227ea) synthesis by fluorinatino of hepafluoroproylene(HFP) over activated carbon has been studied. The reaction temperature was varied from 5$0^{\circ}C$ to 40$0^{\circ}C$ at a constant feed mole ration and a residence time. The optimized reaction temperature was found to be about 20$0^{\circ}C$ at 2.5HF/HFP mole ratio and 238 sec. residence time. From these reaction conditions, the yield of HFC-227ea was obtained above 99% and the deactivation of activated carbon was not appeared. Accordingly, the activated carbon showed good performance to obtain heptafluoropropane by fluorinatin of hexafluoropropylene.

• Horticultural Science & Technology
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• v.18 no.6
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• pp.783-786
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• 2000

This study was carried out to examine the effect of root-zone temperatures on seedling growth, mineral contents and antioxidative enzyme activities of grafted watermelon. The grafted watermelon seedlings were grown in greenhouse bed for 20 days at root-zone day temperatures of 10, 15, $25^{\circ}C$ while night temperature was maintained at $10^{\circ}C$. Growth such as shoot height, leaf length, leaf number, stem diameter, and fresh and dry weights increased as increasing root-zone temperatures, and leaf area with $25^{\circ}C$($52.79mm^2$) was two times that of control($21.50mm^2$). As increasing the root-zone temperatures, Mn, Ca, Fe contents increased, K, P, Mg were non significant, and Na decreased. The activities of ascorbate peroxidase(APX) and guaiacol peroxidase(GPX) known as antioxidative enzyme were higher at $10^{\circ}C$ than $25^{\circ}C$.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.149-153
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• 2004

전통된장 제조방법으로서 원료 혼합비, 메주의 건조시간 및 온도, 메주와 된장의 발효 시간 및 온도, 된장 간장의 분리 여부, 된장 숙성(aging) 시간을 조사하였다. 혈액응고 저해 활성(anticoagulant activity)을 fibrin clotting assay법으로 분석하여 혈액응고 저해활성과 제법간의 상관 관계를 검토하였다. 숙성 기간이 길수록 혈액응고 저해활성이 높게 나타나는 경향을 보였으나 선형적인 상관관계보다는 비선형적으로 양의 상관관계를 갖는 것으로 판단되었다. 이상의 결과를 토대로 혈액응고 저해활성이 높은 2종의 된장시료를 선발하였으며 숙성기간이 180일 이상일 경우 전통된장의 혈액응고 저해활성이 높은 것으로 판단되었다.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.121-124
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• 2003

Optimal extraction condition and free radical scavenging effect of ethanol extracts of Olympia grape (Vitis labruscana L.) seeds and skins were determined. Extraction yield of grape seeds increased with increasing extraction temperature increased, but was not affected by ethanol concentration in grape skins. Highest extraction yields obtained with 100% ethanol concentration at $78^{\circ}C$ were 36 and 49.5% in seeds and skins, respectively. Ethanol extract of grape seeds obtained at $78^{\circ}C$ showed stronger $RC_{50}\;(409.7\;{\mu}g/mL)$ than that of grape skins. Among organic solvent fractions, ethylacetate fraction obtained from ethanol extract of grape seed showed the strongest $RC_{50}\;(136.7\;{\mu}g/mL)$. Overall, ethanol extracts of grape seeds and their organic fractions showed significantly stronger free radical scavenging effect than those of skin extracts.