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        검색결과 687

        181.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        현 국제해사기구(IMO)에서의 선박엔진에서 발생되는 NOx와 SOx 등의 연소 가스 배출에 대한 규제 강화에 따라, 발트 해 연안을 지나는 모든 선박들은 배출되는 연소가스 저감장치를 장착해야 된다. 국내에서도 IMO의 규제에 따른 NOx와 SOx를 저감장치를 개발하고 있으며, 그중에 대표적인 장 치인 Scrubber는 세정액으로 암모니아수와 요소수를 사용하게 되고 사용된 폐 세정액에는 NOx와 SOx 와 반응한 질산암모늄과 황산암모늄이 포함되어 있다. 본 연구에서는 폐 세정액이 포함하고 있는 유용한 부산물을 유기용매를 사용하는 염석법을 적용하여 회수하였다. 질산암모늄과 황산암모늄의 회수방법과 질안석회를 추출 후 회수된 부산물의 정성분석을 위하여, FT-IR 분석을 통하여 물질의 정성적 특성과 화학적 조성을 평가해 보았다. 한편 응집제를 투입하여 질안석회를 침전시켜 비료상의 물질로 회수하였 다. FeSO4 응집제와 CaCl2를 응집보조제로 사용하고 입자의 크기를 키우기 위해 CaCO3를 사용하였다.
        4,000원
        182.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        선박엔진에서 발생하는 NOx 및 SOx 제거용 스크러버 폐세정액에 포함되어 있는 저농도상 의 질산 및 황산이온을 비료상 물질로 회수하고자 하였다. 본 연구에서는 네 가지 유기용매를 적용하여 선택적으로 추출하여 회수하는 방법을 시험하였다. 아세톤과 메틸알콜을 이용하여 추출한 질산암모늄과 디에틸에테르와 에틸알콜을 적용한 황산암모늄의 시료를 적외석흡수분광법(IR)을 이용하여 분석한 결과, 상용제품과 거의 동일한 구성성분으로 나타났다. 이때 폐수로부터의 회수율은 최대 89%와 80%까지 각 각 얻을 수 있었다. 따라서 배기가스 스크러버에 잔존해있는 질산이온과 황산이온에 대한 회수는 사용하 는 용매의 선택도 및 용해도가 핵심적인 요소인 것으로 판단된다.
        4,000원
        183.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were 77.0±4.3% and 81.5±1.3% at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group (67.8±4.3%) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.
        4,000원
        184.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were 77.0±4.3% and 81.5±1.3% at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group (67.8±4.3%) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.
        4,000원
        188.
        2017.04 구독 인증기관·개인회원 무료
        Angelica gigas Nakai has been used for traditional Korean medicine which acts anti-inflammatories, protects the liver, and enhances the immune system. Subcritical water extraction (SWE) is an eco-friendly extraction method in which the pressure is applied between the boiling point and critical temperature of water that maintains the liquid state. The aim of study was to determine the optimal extraction conditions for subcritical water extraction of the decursin and nodakenin from Angelica gigas Nakai, comparing two scales, laboratory-scale (22 mL) and pilot-scale (8 L) devices to assess the feasibility of industrial applications. Extraction efficiencies were evaluated by measuring total polyphenol contents and DPPH radical scavenging activity with a spectrophotometer, extraction yields of decursin and nodakenin with a high-performance liquid chromatography. The subcritical water extraction conditions of pilot-scale were as follows: extraction temperature of 150, 170, 190 and 210°C; extraction times of 5, 10, 15, and 20 min. The highest yields of decursin and nodakenin were at 190°C/15 min (17.65 mg/g Angelica gigas) and 170°C/20 min (4.35 mg/g Angelica gigas), respectively. These were not significantly different from the maximum contents of decursin (13.49 mg/g Angelica gigas), and nodakenin (4.66 mg/g Angelica gigas) for lab-scale subcritical water extraction. The maximum values for total polyphenol content and DPPH scavenging activity of subcritical water extraction were 64.32 mg/g Angelica gigas and 74.4%, respectively. On the other hand, those of conventional extraction method using methanol (60°C/120 min) were obtained as 14.31 mg/g Angelica gigas and 41.9%. Therefore, the subcritical water extraction is a rapid and efficient method for extracting polyphenols and anti-oxidative compounds.
        189.
        2017.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In the present study, biomass-based lignin was extracted from industrial waste black liquor and the extracted lignin was characterized by means of attenuated total reflectance- Fourier transform infrared spectroscopy and 1H-nuclear magnetic resonance spectroscopy. The extracted lignin was carbonized at different temperatures and then activated with steam at 850oC. The extracted lignin in powder state was transformed into a bulky carbonized lignin due to possible fusion between the lignin particles occurring upon carbonization. The carbonized and then pulverized lignin exhibits brittle surfaces, the increased thermal stability, and the carbon assay with increasing the carbonization temperature. The scanning electron microscopic images and the Brunauer-Emmett-Teller result indicate that the steam-activated carbon has the specific surface area of 1718 m2/g, which is markedly greater than the carbonized lignin. This study reveals that biomassbased activated carbon with highly porous structure can be produced from costless black liquor via steam-activation process.
        4,000원
        191.
        2017.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We plan to produce a faint source catalogue from the AKARI mid-infrared (IR) all-sky diffuse maps. In the publicly-available AKARI mid-IR point source catalogue (PSC), sources were extracted from single- scan images, and con rmed by using the other scan images. By stacking multiple scan images, we can detect fainter sources which are not listed in the PSC. We optimized the source extraction process using a 6◦  6◦ area around the star-forming region, Cepheus B. Then, we divided the all-sky data into three seasonal images, and checked the positions and the uxes of the detected sources on the images. As a result, our new source extraction method works well; 90% of the sources are also identi ed in the WISE catalogue. In this method, we obtain the detection limit twice deeper than that of the PSC. The number of sources increases by a factor of 2, as compared with the PSC.
        3,000원
        192.
        2017.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 케일의 항산화 활성을 평가하고, 기능성 육제품 개발 및 천연 항산화제로의 이용가능성을 알아보기 위해 수행되었다. 케일을 열풍건조하여 물, 에탄올, 80% 에탄올로 추출한 후 항산화활성을 평 가하였다. 총 페놀성 화합물 함량은 1.14-2.45g/100g의 범위를 보였으며 에탄올 추출물이 물과 80% 에탄올 추출물에 비해 유의적으로 낮은 함량을 보였다. 에탄올과 80% 에탄올 추출물이 물 추출물보다 높은 DPPH 라디칼 소거능 및 환원력을 보인 반면, 철이온 흡착력에서는 물 추출물이 다른 처리구보다 유의적으로 높은 활성을 보였다. 이러한 연구결과를 바탕으로 케일 80% 에탄올 추출 분말을 각 농도별 (0.1, 0.25, 0.5, 1.0%)로 돈육 패티에 첨가하여 제조하였으며, 14일 동안 4℃에서 냉장저장하며 이화 학적 특성 및 항산화 활성을 평가하였다. pH는 케일 1%를 첨가한 처리구4(TRT 4, 케일 1.0%)에서 가 장 낮은 값을 보였다. 색도에서는 첨가량이 증가할수록 명도 값이 감소하였으며, 케일 0.5%와 1.0%를 첨가한 처리구 3과 처리구 4의 황색도 값이 가장 높았다. 저장기간이 경과할수록 TBA와 POV값은 증가 하였으며, 저장 14일째에 대조구보다 케일을 첨가한 처리구가 낮은 TBA값을 보였으며, 마찬가지로 저 장 14일째에 케일을 첨가한 처리구가 대조구(CTL)보다 유의적으로 낮은 POV를 보였다. 총균수와 대장 균군수는 처리구에 따른 차이가 없었으며, 저장기간이 경과함에 따라 값이 증가하였다. 이와 같은 결과 에 따라 케일 80% 에탄올 추출물이 육제품에서 천연 항산화제로의 이용이 가능할 것으로 판단된다.
        4,600원
        193.
        2017.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was carried out to extract ginsenosides in by-products from honeyed red ginseng. Response surface methodology (RSM) was used to optimize the extraction conditions. Based on D-optimal design, independent variables were ethanol (extraction solvent) concentration (30-90%, v/v), extraction temperature (25-70oC), and extraction time (5-11 h). Extraction yield (Y1) and total ginsenosides (Y2) in the extract were analyzed as dependent variables. Results found that extraction yield increased with increasing extraction temperature and time, whereas it was decreased with increasing ethanol concentration. Similar trends were found for the content of ginsenosides in the extracts, except for ethanol concentration, which was increased with increasing ethanol concentration. Regression equations derived from RSM were suggested to coincide well with the results from the experiments. The optimal extraction conditions for extraction yield and total ginsenosides were an extraction temperature of 56.94oC, ethanol concentration of 57.90%, and extraction time of 11 h. Under these conditions, extraction yield and total ginsenoside contents were predicted to be 84.52% and 9.54 mg/g, respectively.
        4,000원
        194.
        2017.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Antioxidant activities of 80% methanol, water, and 70% ethanol extracts of Lentinula edodes GNA01 were compared and estimated. The yield of Lentinula edodes GNA01 was identified to be in the following order: water>70% ethanol>80% methanol, but there was no significant difference between 80% methanol and 70% ethanol extracts. The highest total phenolic content (TPC) and total flavonoid content (TFC) were found in water extract, and TPC of 80% methanol extract was higher than that of 70% ethanol extract and TFC of 70% ethanol extract was higher than that of 80% methanol extract. Water extract exhibited the strongest DPPH, ABTS radicals, and nitrite scavenging activities, Fe2+ chelating ability, and FRAP among the three extracts. In addition, antioxidant activity of 80% methanol extract was higher than that of 70% ethanol extract in most of the experiments. As a result, antioxidant activity of Lentinula edodes GNA01 showed a difference according to extraction solvent and concentration; nevertheless, water extract exhibiting high polarity had the strongest antioxidant effect. Consequently, water extract from Lentinula edodes GNA01 is anticipated to be useful for the development of a high value-added functional product
        4,000원
        195.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The acai berry (Euterpe oleracea Mart.) contains vitamin B complex, vitamin C, anthocyanin and so on. Especially acai berry was seen as nutritionally comparable to blueberry and related berries. The acai berry has significant aging-reducing properties. Compounds have been found to have anti-aging and antioxidant components. Acai berry was extracted with 70% methanol, 70% ethanol and CM (chloroform:methanol=2:1, v/v). After sample and reagents of each experiment was reacted, DPPH radical scavenging activity and ABTS radical scavenging activity, ferric reducing antioxidant power, reducing power were measured to determine the antioxidant capacity, and as results of comparing each extract. Ethanol (70%) extraction was measured highest. Anthocyanin, total phenol, flavonoid also appeared similar to the results. In addition, the antioxidant activities of the extraction solvents were increased significantly with increasing concentrations, but showed lower antioxidant activity than the positive control (ascorbic acid). As a result, antioxidant activities of sample supposed to affect by the anthocyanin, phenol and flavonoid contents.
        4,000원
        196.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The total polyphenol and physiological activities of Pleurotus ostreatus 30% fermented ethanol using different drying methods and extraction periods were investigated. Based on the observed polyphenol content and physiological activity, freezedrying showed better results than hot air-drying method for P. ostreatus extracted with 30% fermented ethanol for more than 15 days. The total phenolic compound content of ‘Gosol’ following thefreeze-drying method for 15 days showed the highest value of 0.49±0.02 mg/mL. Freeze-drying with extraction for 30 days for ASI 2344 showed the highest antioxidant activity based on the DPPH radical scavenging rate of 35.50±3.29%. Freeze-drying ‘Gosol’ for 30 days resulted inthe highest anti-inflammatory and nitrite scavenging activity of 48.40±3.38%. Our results showed that P. ostreatus is a functional food.
        4,000원
        197.
        2016.10 구독 인증기관·개인회원 무료
        Vespa velutina nigrithorax prey on various insect and especially hunts domestic honeybees, such as the European honeybee, Apis melifera. For that reason, V. velutina predation has a direct economic impact on apiculture. In particular V. velutina queens are able to establish of new colonies, so they are suitable for V. velutina management. This study was conducted to investigate the attractant of V. velutina Queen. Four traps were tested and combined attractant such as honeybee comb extraction, honeybee extraction, pollen, rice wine and sugar syrup for attraction efficacy. We was able to observe V. velutina Queen in late April to May. And Honeybee extraction, rice wine and sugar syrup baits (5 : 3 : 2) was the best combination for trapping queen on spring.
        198.
        2016.10 구독 인증기관·개인회원 무료
        Opuntia is a cactus with fruits and is also called prickly pear. Extraction process of water soluble fiber from opuntia stem powder was optimized by applying various conditions such as ethanol concentration, temperature and pH. Fiber extraction was highest in 0% ethanol and lowest in 100% ethanol, indicated that hot distilled water extraction produced maximum water soluble fiber. Among temperature range from 50 to 90°C, water soluble fiber was extracted mostly at 50°C and leastly at 90°C, showing decrease in fiber with increase in temperature. On the other hand, pH higher than 7 did not show any significant difference in fiber extraction, while fiber extraction decreased in lower pH 7. Conclusively ethanol hampered extraction of water soluble fiber from opuntia stem powder and extraction was not stable with higher heat and low acidic condition.
        199.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        선행연구에서 화장품 소재로서 보습력과 방부력을 가지고 있는 1, 2-hexanediol (HD)의 transgalactosylation 반응을 통하여 galactose한 분자가 HD에 결합한 1, 2-hexanediol galactoside (HD-gal)의 합성을 확인하였다. 본 연구에서 재조합 β-galactosidase (β-gal)가 발현된 Escherichia coli (E. coli) 세포를 이용하여 약 94%의 수율로 HD-gal가 합성되는 것을 관찰하였고, HD-gal을 합 성한 후, 보다 효과적인 HD-gal의 정제 방법에 대하여서도 연구하였다. 먼저 고농도의 lactose (300 g/l) 존재 하에서 β-gal을 함유한 E. coli 세포를 이용하여, 48 시간 동안 75 mM의 HD로 부터 HD-gal이 합성되는 것을 TLC 분석으로 확인하였고, 반응액에서 E. coli β-gal의 존재를 Western blotting으로 확인할 수 있었다. HD-gal을 효과적으로 순수 정제하기 위하여, 용매를 사용하여 transgalactosylation 반응이 끝난 후 잔여 HD를 우선 제거하고, 이어서 silica gel chromatography를 수 행하는 방법을 실시하였다. 물에 녹지 않는 용매로는 methylene chloride와 ethyl acetate를 선택하여 비 교 실험하였는데, ethyl acetate를 사용하여 4회 물층을 분획하여, 잔여 HD를 효과적으로 제거할 수 있 었다. 그 후, 이어서 silica gel chromatography 수행하여, 순수한 HD-gal을 효과적으로 정제하였다. 반 응에 첨가된 75 mM의 HD를 기준으로 최종 정제된 HD-gal의 생산 수율은 mole 기준으로는 약 8.9±0.6% (n=3), weight 기준으로 약 21.1±1.4% (n=3) 정도였다. 앞으로 이러한 정제 방법을 이용하 여 얻은 HD-gal의 항균력 변화를 HD와 비교하여 평가할 예정이고, 피부세포에 대한 독성 변화를 역시 HD와 비교하여 분석할 예정이다.
        4,000원
        200.
        2016.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 초음파 진동에 의해 발생하는 공동현상을 이용하여 다양한 유용성분과 생리활성을 가지고 있는 녹차와 애엽을 혼합하여 새로운 식품소재를 개발하기 위해서 반응표면분석법에 의한 추출특성을 모니터링 하여 최적 추출조건을 예측하였다. 초음파를 지속적으로 가하는 조건에서 Box-Behnken design에 의해 녹차와 애엽의 혼합비, 용매와 용질의 비, 추출시간을 독립변수로 하여 15구간의 추출조건을 설정하고 추출수율(Y)을 종속변수로 하여 모니터링 하였다. 반응표면분석결과 녹차 및 애엽 혼합 추출물은 녹차의 함량과 추출용매의 양이 증가 할수록 추출 수율이 증가 하였으며, 추출시간은 결과에 큰 영향을 주지 않는 것으로 나타났다. 추출수율을 최대로 얻을 수 있는 녹차 및 애엽 혼합물의 최적 추출조건은 녹차와 애엽의 혼합비 85.86%, 용매와 용질의 비 92.73 mL/g, 추출시간 56.52분으로 확인되었으며, 추출수율의 최대값은 30.03% 로 예측되었다.
        4,000원