• 한국식품조리과학회지
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• 제28권3호
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• pp.275-283
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• 2012

본 실험은 반응표면분석법을 이용하여 야관문 에탄올 추출물의 기능성분에 대한 추출조건을 최적화하였다. 추출조건에 따른 수율의 최대값은 17.6%이었고, 중심합성계획에 의한 야관문의 추출조건별 총 폴리페놀 및 총플라보노이드 함량에 대한 반응표면 회귀식의 $R^2$는 각각 0.8562와 0.9787로 10% 및 1%이내의 유의수준에서 유의성이 인정되었다. 야관문 에탄올 추출물의 폴리페놀 및 플라보노이드 함량 변화는 추출온도와 추출시간보다는 에탄올 농도에 크게 영향을 받고 있는 것으로 나타났다. 전자공여능에 대한 회귀식의 $R^2$는 0.8344로 10% 이내의 유의수준에서 유의성이 인정되었다. pH 조건에 따른 야관문의 아질산염 소거능에서 최대점을 보인 pH 3.0에서는 추출온도가 증가할수록 에탄올 농도 범위가 40~60% 범위에서 우수함을 확인하였다. ORAC은 1,636.47~2,696.99 ${\mu}moles$ TE/g의 범위였으며, 결과에 대한 반응표면 회귀식의 $R^2$는 0.8383로 10%이내의 유의수준에서 인정되었고 추출온도보다는 추출시간과 에탄올 농도에 영향을 받는 것으로 나타났다. 야관문의 추출조건을 최적화하기 위하여 추출물의 특성인 조건별 추출물의 수율, 총 폴리페놀함량, 전자공여능, 아질산염 소거능 및 ORAC에 대해 contour map을 superimposing하여 얻은 최적조건의 범위는 추출온도 $78{\sim}85^{\circ}C$, 추출시간 6~7시간, 에탄올 농도 38~60%이었다.

• 한국수산과학회지
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• 제31권1호
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• pp.82-89
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• 1998

미역과 큰 다시마 알긴산의 염산 부분가수분해에 의한 저분자화 조건을 구명하였으며, 저분자화가 알긴산의 점성, 용해도, 유화능, 흡유능, 담즙산결합능 및 금속이온결합능 등의 물성에 미치는 영향에 관하여 검토하였다. 미역에서 추출한 알긴산을 시료로 하여 저분자화의 조건을 검토한 결과, 염산에 의한 반응시간의 연장 및 염산의 농도증가와 더불어 구성 polyuronate의 중합도는 급격히 감소하였다. 그리고 0.3N HCl 부분가수분해에 의하여 분자량을 1/100로 감소시키는데 소요되는 반응시간은 약 50분이었고, 이 때 각각의 수율은 약 $75\%\~80\%$ 이었다. 각 알긴산의 M/G의 비는 저분자화에 의하여 증대하였으며, 알긴산 용액의 점성은 저분자화하므로서 급격히 저하하였고, 알긴산의 점도와 분자량은 밀접한 상관관계를 보였다($r^2=0.9890$). 온도단계별 ($5\~40^{\circ}C$)로 측정한 알긴산의 용해도는 수용성 알긴산이 산$\cdot$알칼리가용성 알긴산에 비하여 $7\~12\%$ 높았으며, 저분자화와 더불어 상승하였다. 한편, 저분자화는 유화능의 증가를 가져왔으며, 용해도와는 비슷한 관계를 보였다. 그러나 흡유능과 금속이온결합능은 저분자화에 의하여 감소하였으며, 특히 금속이온결합능에 있어서는 미역 알긴산은 $Pb^{2+},\;Cu^{2+},\;Zn^{2+},\;Co^{2+}$의 순으로, 그리고 큰 다시마 알긴산은 $Cu^{2+},\;Pb^{2+},\;Zn^{2+},\;Co^{2+}$의 순으로 각각 감소하였다. 담즙산결합능은 저분자화와 더불어 오히려 증가하는 특징을 보였다.

• 한국식품저장유통학회지
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• 제19권6호
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• pp.901-908
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• 2012

본 연구는 건대추와 건대추를 이용하여 온도 $50^{\circ}C$, 습도 90%의 항온항습기에서 숙성시켜서 제조한 발효 흑대추의 열수 및 에탄올 추출물에 항산화성을 평가함으로서 대추의 식품학적인 기능성을 검토하고자 하였다. 건대추와 발효 흑대추의 열수 및 70% 에탄올 추출물의 수율은 발효 흑대추 추출물에서 높았으며, 70% 에탄올 추출물이 열수 추출물에 비해 높았다. 총 폴리페놀 함량은 흑대추 추출물에서 높게 나타났으며, 열수 추출물이 70% 에탄올 추출물보다 높은 함량을 보였다. 전자공여능은 건대추와 발효 흑대추의 추출물의 열수 및 에탄올 $1,000{\mu}g/mL$의 농도에서 각각 85.0% 이상의 전자공여능을 보였고, SOD 유사활성능은 발효 흑대추 추출물이 건대추 추출물에 비해 높았으며, 대체적으로 열수 추출물에서 높게 나타났다. pH 1.2에서의 아질산염 소거능은 에탄올 추출물에 비해 열수 추출물에서 높았으며, 발효 흑대추보다 건대추 추출물에서 높게 나타났다. Xanthine oxidase 저해활성은 건대추 및 흑대추 추출물의 농도가 증가함에 따라 증가하였으며, 열수 및 에탄올 추출물에서는 건대추에 비해 발효 흑대추 추출물의 저해활성이 높았다. 이상의 결과로 발효 흑대추의 열수 및 에탄올 추출물에서 높은 항산화 활성을 확인 할 수 있었으며, 발효 흑대추는 우수한 기능성 식품으로서의 가능성을 확인할 수 있었다.

• Journal of Photoscience
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• 제9권2호
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• pp.162-165
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• 2002

Rice is widely cultivated in various regions throughout Asia. Over a five-year period, we investigated the effects of supplemental UVB radiation on the growth and yield of Japanese rice cultivars in the field. The findings of that study indicated that supplemental UVB radiation has inhibitory effects on the growth and grain development. Furthermore, we investigated the sensitivity to UVB radiation of rice cultivars of 5 Asian rice ecotypes, and found that rice cultivars vary widely in UVB sensitivity. The aim of our study is improving UVB resistance in plants by bioengineering or breeding programs. In order to make it, there is need to find the molecular origin of the sensitivity to UVB. Cyclobutane pyrimidine dimer (CPD) is major UV-induced DNA lesions. Plants possess two mechanisms to cope with such DNA damage. The first is the accumulation of UV-absorbing compounds. Our previous data showed that the steady-state CPD levels in leaves of rice grown under chronic radiation in any culture were not so greatly influenced by the increased UV-absorbing compounds content, although there was a significant positive correlation between the CPD levels induced by challenge UVB exposure and the UV-absorbing compounds content. The other is the repair of DNA damage. Photorepair is the major pathway in plants for repairing CPD. We found that the sensitivity to UVB could seriously correlate with the low ability in CPD photorepair in rice plants. These results suggest that photo lyase might be an excellent candidate for restoration by way of selective breeding or engineering in rice.

• 공학교육연구
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• 제16권3호
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• pp.10-19
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• 2013

Recently, Korean universities have increased the number of English Medium Instruction (EMI) lectures in order to allow students to gain both specialized knowledge and enhanced English ability. Previous researches on effective EMI lectures have focused on exploring the effects of learners' cognitive and affective characteristics on learning outcomes. Whereas the input variables of learning have been investigated as predicting variables of effects in EMI lectures, there has been a few research for investigating process variables to yield learning outcomes. The purpose of this study is to analyze the structural relationships among variables affecting on learner satisfaction and effects. The participants are 209 engineering students from various majors. Independent variables are defined as English motivation, English competency, and English confidence, a mediated variable is Cognitive engagement, and dependent variables are Learning satisfaction and Educational effect perception. The results show that the relationships are statistically significant: learners' English competency & English confidence ${\rightarrow}$ Cognitive engagement ${\rightarrow}$ Learning satisfaction ${\rightarrow}$ Educational effect perception. Especially, the structural model confirms that the effect of learners' English confidence on Learning satisfaction and Educational effect perception is mediated by the level of learners' Cognitive engagement. Further, the implication for effective EMI lectures is discussed based on the observed research results.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1869-1874
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• 2010

By reducing PVP with $H_2NOH$.HCl and NaOH 2:2:1 mass ratios in aqueous ethanol, poly-N-vinyl pyrrolidone oxime [PVPO] was prepared with 92% yield. Applying the sol-gel concept, orthosilicic acid [OSA] was made by hydrolyzing TEOS with ethanol in 1:0.5 molar ratios using 1 N KOH aqueous solution as a catalyst. The OSA + PVPO + $_L$-Valine ($\alpha$-amino acid) were mixed with pure ethanolic medium in 1:2:2 mass ratios and refluxed at $78^{\circ}C$ and 6 pH for 6.5 h. A white residue of poly-N-vinyl pyrrolidone oximo-L-valyl-siliconate [POVS] appeared after 5 h. The heating of reaction mixture was stopped and the contents were brought to NTP. The residue formation of POVS was intensified with lowering a temperature and completely solidified within 5 h, was filtered using a vacuum pump with Whatmann filter paper no. 42. The residue of POVS was washed several times with 20% aqueous cold ethanolic solution and dried in vacuum chamber at $25^{\circ}C$ for 24 h. The MP was noted above $350^{\circ}C$. Structural and internal morphology were analyzed with IR and $^1H$-NMR, and SEM respectively. A drug loading and transporting ability of the POVS in water and at pH = 5 and 8 was determined chromatographically.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.81.1-81
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• 2003

Although plants have evolved to possess various defense mechanisms from local biotic and abiotic stressors, most of yield loss is caused by theses stressors. Recent studies have revealed that several different stress responsive reactions are inter-networking. Therefore, the identification and dissection of stress responsive genes is an essential and first step towards understanding of the global defense mechanism in response to various stressors. For this purpose, we applied cDNA microarray analysis, because it has powerful ability to monitor the global gene expression in a specific situation. To date, more than 10,000 non-redundant genes were identified from seven different cDNA libraries and deposited in our EST database (http://plant.pdrs.re.kr/ks200201/pepper.html). For this study, we have built 5K cDNA microarray containing 4,685 unigene clones from three different cDNA libraries. Monitoring of gene expression profiles of hot pepper interactions with biotic stress, abiotic stresses and chemical treatments will be presented. Although this work shows expression profiling at the sub-genomic level, this could be a good starting point to understand the complexity of global defense mechanism in hot pepper.

• 수산경영론집
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• 제47권4호
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• pp.65-75
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• 2016

The purpose of this study was to analyze the production and marketing control effects of aqua-cultured flounder required for stable income growth of aqua-cultured household. We analyzed the supply and demand structure of cultured flounder using the partial equilibrium model approach. And we estimated the optimal yield of cultured flounder and analyzed the effect of marketing control through constructed model. The main results of this study are summarized as follows. First, the fitness and predictive power of the estimated model showed that the RMSPE and MAPE values were less than 5% and Theil's inequality coefficient was very close to 0 rather than 1. It was evaluated that the prediction ability of the aqua-cultured flounder supply and demand model by dynamic simulation was excellent. Second, dynamic simulation based on policy simulation was conducted to analyze the price increase effect of production and shipment control of cultured flounder. As a result, if the annual production volume is reduced by 1%, 5%, and 10% among 32,852~37,520 tons, it is analyzed that the price increase effect is from 1.2% to 12.5%. Finally, this study suggests that the production and marketing control can increase the price of aqua-cultured flounder in the market. In this paper, we propose a policy implementation of the total supply system instead of conclusions.

• ALGAE
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• 제19권1호
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• pp.59-68
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• 2004

Hizikia fusiformis hydroysates by five carbohydrases (Viscozyme, Celluclast, Termamyl and Ultraflo) and five proteases (Protamex, Kojizyme, Neutrase, Flavourzyme and Alcalase) were investigated for their extraction efficacy (yield and total total polyphenolic content) and antioxidative activity (DPPH radical and hydrogen peroxide scavenging activity). Termamyl and Ultraflo of the carbohydrases and Flavourzyme and Alcalase of proteases were selected by their high eficacy of extraction and antioxidative activity. Selected enzymes were used to investigate the optimum enzymatic reaction time and dosage (enzyme/substrate ratio) suitable for hydorolysis. Optimum reaction time for the enzymatic hydrolysis was 3 days and optimum dosage of hydrolysis was observed as 5%. Simultaneously, Ultraflo of the two carbohydrases and Alcalse of the two proteases were selected as the most effective enzymes. Combination of Ultraflo and Alcalase under optimum hydrolysis conditions could intensify the extraction efficacy of antioxidative materials form H. fusiformis. The hydrolysate obtained by combining the enzymes was separated into four different molecular weight fractions (<1kD, 1-10 kD, 10-30 kD and >30 kD) and recorded the polyphenolic content distribution and respective antioxidative ability. The fraction <1kD was identified as less effective and those fractions > 1kD indicated comparatively higher antioxidative activities related to their polyphenolic content.

• 한국소음진동공학회논문집
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• 제22권1호
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• pp.81-87
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• 2012

This paper establishes a modeling and simulation procedure for structural response and reliability of a cylindrical array sensor on submarines under the shock generated by underwater explosion. The structural reliability of SONAR is important because the submarine could get out of combat ability by the structural damage of the SONAR upon explosion. A cylindrical array sensor was first modeled using the finite element method. Modal analysis was then performed for the check of the reliability of the modeling. The shock resistance simulations were performed for the responses to the structural shock waves and for the responses to the directly applied underwater shock waves, according to BV-043 and MIL-STD-901D, respectively. The stresses of the structure were evaluated with von-Mises scheme. Vulnerable regions were exposed through mapping the maximum stress to the structural model. Maximum stress of the SONAR was compared with the yield stress of the material to examine the structural reliability.