• 에너지공학
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• 제2권1호
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• pp.68-74
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• 1993

본 연구에서는 감압잔사유의 활용을 극대화하는 것을 목적으로 초임계 용매 추출법을 이용하여 탈아스팔트오일을 추출하였다. 초임계 용매로 n-pentane을 사용하였으며 온도와 압력 변화에 따른 추출수율과 추출된 오일 중 금속성분 및 황성분 함량의 변화가 조사되었다. 탈아스팔트오일의 추출수율은 사용한 용매의 초임계 영역에서 밀도에 크게 좌우됨이 조사되었고 추출유의 금속성분 함량은 감압잔사유에 비하여 크게 제거되었으나, 황성분 제거율은 낮았다.

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1421-1425
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• 2018

The dynamics of gas release at thermal oxidation of extraction systems on the basis of diamides of dicarbonic acids in fluorinated sulphones with 14 mol/L $HNO_3$ was investigated. The effect of preirradiation of the mixtures with accelerated electrons on the kinetics of their thermolysis was determined. The mixtures were heated in an autoclave at temperatures of 170 and $200^{\circ}C$ and irradiated using an electron accelerator to absorbed doses of 0.1, 0.5, and 1.0 MGy. It has been shown that no conditions for autocatalytic oxidation at thermolysis of extraction mixtures irradiated up to a dose of 1 MGy were developed.

• Fisheries and Aquatic Sciences
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• 제15권4호
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• pp.275-281
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• 2012

Yellow croaker Larimichthys polyactis muscle oil was extracted using an environmental friendly solvent, supercritical carbon dioxide (SC-$CO_2$), in a semi-batch flow extraction process. SC-$CO_2$ was applied at temperature $35^{\circ}C$ to $45^{\circ}C$ and $150^{\circ}C$ to $250^{\circ}C$ bar of pressure. The flow rate of $CO_2$ (27.79 g/min) was constant throughout the entire 1.5 h extraction period. The oil extraction yield was influenced by the physical properties of SC-$CO_2$ at different temperatures and pressures. The extracted oil was analyzed by gas chromatography to determine the fatty acid composition. According to our results, the SC-$CO_2$ extracted oil was high in eicosapentaenoic acid and docosahexaenoic acid. In addition, the SC-$CO_2$ extracted oil showed greater stability than n-hexane extracted oil based on the peroxide value and acid value. Thus, the quality of yellow croaker oil obtained by SC-$CO_2$ extraction was slightly higher than that of oil obtained by n-hexane extraction.

• 농업과학연구
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• 제51권3호
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• pp.361-373
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• 2024

Syzygium formosum has been traditionally used in Vietnam as a folk medicine for treating skin and respiratory diseases. With the recent recognition of its beneficial effects such as anticancer, antioxidant, and anti-inflammatory properties, there is an increasing interest in industrial extraction of its bioactive compounds, such as triterpenoids and flavonoids. In this study, the extraction efficiencies of S. formosum were analyzed by extraction methods and harvest timings. Firstly, it was found that distilled water treatment substantially eliminated almost all flavonoids, suggesting that minimal pretreatment is important to preserve both triterpenoids and flavonoids. Secondly, extractions with 70% ethanol at both lab and pilot scales effectively yielded more than 70% of triterpenoids and flavonoids from S. formosum. Lastly, to investigate the seasonal variation in phytochemicals, extracts from the leaves of S. formosum harvested in April, August, October, and December in Vietnam were analyzed. It was revealed that seasons with lower temperatures led to higher concentrations of triterpenoids and flavonoids. Specifically, December was found to be optimal for obtaining high concentrations of triterpenoid and October for flavonoid. Consequently, this research provides a foundation for the industrial application of S. formosum, providing critical insights into maximizing the extraction efficiency and phytochemical contents through optimized processing methods and strategic harvesting.

• 대한약침학회지
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• 제21권2호
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• pp.48-60
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• 2018

Objective: The aim of this study is to optimize the extraction of beneficial substance from Cudrania tricuspidata leaves grown at Jirisan Mountain in South Korea by three different solvents depending on extraction time and at different temperature. Methods: The total phenolic contents were determined by the method reported by $S{\acute{a}}nchez$-Moreno et al. The total flavonoid contents were analyzed by Slinkard and Singleton. The DPPH radical scavenging activity was determined according to the method reported by Blois Results: The extraction yield for each solvent is 9.05-14.1%, 2.17-5.67%, and 2.3-3.9% for D.W., ethanol, and hexane, respectively. The overall results were maximized for the extract obtained with D.W. for 5 min at $100^{\circ}C$. The average phenol contents were 77.11, 45.64, and 0.343 mg/g at $100^{\circ}C$ in water, $78^{\circ}C$ in ethanol, and $68^{\circ}C$ in hexane, respectively. The flavonoid contents were the highest in the materials extracted with D.W., and were increased with increasing temperature, regardless of the extraction solvents, whether water (green), polar organic ethanol, or nonpolar organic hexane. In the ethanol extract, the flavonoid contents are increased gradually from 5.66 mg/g to 7.73 mg/g. The total flavonoid contents were proportional to the concentrations of the water extracts, ranging from 4.14 mg/g to 48.89 mg/g. The antioxidative activities of the water-extracted compounds are generally increased with increasing temperature from 42.5% to 85.5%. Those of the hexane extracts are increased slowly from 3.79% to 8.8%, while those of ethanol extracts are increased from 29.8% to 47.4%. Conclusion: The extraction yields were dependent upon solvents for extraction as well as extraction time and the temperature. The optimal extraction time was 5 min and the extraction yields were increased with increasing temperature excepted hexane. Of the three tested extraction solvents, the greenest solvent of water shows excellent results, suggesting that water is among the most effective solvents for natural sample extractions for general medicinal, pharmaceutical, and food applications.

• 한국식품영양과학회지
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• 제42권11호
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• pp.1776-1782
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• 2013

추출 온도와 시간에 따른 옻나무 부위별 추출물의 총 페놀 및 플라보노이드 함량과 항산화활성을 측정하였다. 옻나무 추출물의 총페놀 함량은 추출 온도 $160^{\circ}C$에서 47.82 mg GAE/g으로 가장 높았으며, $100^{\circ}C$ 이하의 추출 온도에서는 유의적인 차이가 없었으나 $120^{\circ}C$ 이상의 추출 온도에서는 추출 시간 3시간까지는 증가하다가 5시간에서는 감소하였다. 총 플라보노이드는 추출 온도가 증가함에 따라 증가하여 $140^{\circ}C$, 1시간에서 8.04 mg CE/g으로 가장 높은 함량을 나타내었다. DPPH 라디칼 소거활성은 추출 시간의 증가에 따라 증가하여 $140^{\circ}C$, 3시간에서 34.23 mg TE/g으로 가장 높았으며, 그 이후에는 감소하였다. ABTS 라디칼 소거활성은 DPPH 라디칼 소거활성과 유사하였고 $140^{\circ}C$에서 3시간 추출한 수피 추출물에서 51.58 mg AEAC/g으로 높게 나타났다. 총 페놀과 총 플라보노이드 함량과 DPPH와 ABTS 라디칼 소거활성을 감안할 때 옻나무 부위별 효율적인 추출조건은 추출 온도 $140^{\circ}C$와 추출 시간 3시간이었다.

• 한국식품과학회지
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• 제48권3호
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• pp.296-300
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• 2016

The effect of different temperatures (45, 55, 65, and $75^{\circ}C$) on the extraction of ${\beta}$-glucan and the properties of extracted ${\beta}$-glucan were investigated with four different varieties of barley. Jeju naked barley, blue barley, beer barley, and black barley contained 6.85, 5.13, 3.58, and 4.16% of ${\beta}$-glucan, respectively. ${\beta}$-glucan in barley was extracted in the range of 64.88 to 93.84% depending on the extraction temperature and barley variety. The ${\beta}$-glucans in Jeju naked barley, Jeju blue barley, and black barley were optimally extracted at $65^{\circ}C$ for 3 h and Jeju beer barley at $75^{\circ}C$. The extracted ${\beta}$-glucan resolubilized to 43.48-81.73% and the ratio of ${\beta}(1{\rightarrow}3)$ to ${\beta}(1{\rightarrow}4)$ linkage was in the range of 1:3.8-5.8. These results suggest that purification and properties of ${\beta}$-glucan depend not only on the water extraction temperature, but also on the barley variety.

• KSBB Journal
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• 제16권5호
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• pp.442-445
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• 2001

녹차는 최근 많은 건강 식품으로 많은 관심을 받고 있는 물질이며 함암 및 항산화 효과, 면역체계 강화, 항혈전 효과, 피부암 예방, 심장병 예방 콜레스테롤 예방과 같은 효능을 지닌 카테킨 화합물을 포함하고 있다. 본 연구에서는 녹차로부터 카테킨 화합물을 회수하기 위하여 용매 추출과 분배 방법을 사용하였으며 추출 시 용매, 시간과 온도에 따른 회수율을 비교하여 최적 추출 조건을 조사하였다. 실험 결과로부터 얻은 최적추출 조건은 물 8$0^{\circ}C$에서 40분 동안 추출한후 카페인을 제거하기 위하여 클로로포름으로 분배를 실시하고 다시 에틸아세테리트로 분배를 실시하는것이다. 에틸아세테이트 층에는 EGC, EC EGCG, ECG와 같은 카테린 화합물이 분배되어 있다. 더 나아가서는 제조용 액체 크로마토그패를 이용하여 항암 및 항산화 효과가 가장 좋은 EGCG를 얻을 수 있다.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1116-1123
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• 2020

Velvet antler (VA) is a historically traditional medicinal supplement and is well known in Asian countries for its pharmaceutical and health benefits. The objectives for this study were to optimize the hot water extraction (HWE) of VA for the Korean VA industry, and to determine the most effective pretreatment method among microwave (MW), ultrasonication (US), and enzymatic (EZ) techniques. Using response surface methodology, optimum extraction temperatures and times were determined by central composite design configuration based on extraction yield and sialic acid content. Various quality parameters of VA extract including yield, soluble solid, protein, and sialic acid contents were also compared with the conjunction of HWE and pretreatment. The yield and sialic acid content of VA extract were determined to be 40% and 0.73 mg/g, respectively, under an optimum temperature of 100℃ at 24 h of extraction time. The yields from VA extracts pretreated with MW, US, and EZ were 17.42%, 19.73%, and 29.15%, respectively. Among the tested commercial enzymes, pepsin was the most effective proteolytic enzyme and led to the highest yield (47.65%), soluble solids (4.03 °brix), protein (1.12 mg/ml), and sialic acid (3.04 mg/ml) contents from VA extract.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3798-3807
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• 2021

Tritium extraction from radioactively contaminated cement mortar samples was performed using heating and liquid scintillation counting methods. Tritiated water molecules (HTO) can be present in contaminated water along with water molecules (H₂O). Water is one of the primary constituents of cement mortar dough. Therefore, if tritium is present in cement mortar, the buildings and structures using this cement mortar would be contaminated by tritium. The radioactivity level of the materials in the environment exposed to tritium contamination should be determined for their disposal in accordance with the criteria of low-level radioactive waste disposal facility. For our experiments, the cement mortar samples were heated at different temperature conditions using a high-temperature combustion furnace, and the extracted tritium was collected into a 0.1 M nitric acid solution, which was then mixed with a liquid scintillator to be analyzed in a liquid scintillation counter (LSC). The tritium extraction rate from the cement mortar sample was calculated to be 90.91% and 98.54% corresponding to 9 h of heating at temperatures of 200 ℃ and 400 ℃, respectively. The tritium extraction rate was close to 100% at 400 ℃, although the bulk of cement mortar sample was contaminated by tritium.