• 생명과학회지
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• 제10권2호
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• pp.202-209
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• 2000

The factors affecting chemical composition of green tea (Camellia sinensis L.) during extraction process were temperatures and times. The optimum extraction conditions were measured in relation to the changes of chemical compositions from water extracts of green tea (Camellia sinensis L.) under different extraction temperatures (50, 70, 9$0^{\circ}C$) and extraction times (1, 3, 5 minute). The change of color intensity during browning reaction, flavonoid components, contents of total phenols and hydrogen donating activity (reducing activity for $\alpha$, $\alpha$'-diphenyl-$\beta$ -picryhydrazyl) of water extracts form green tea increased as extraction temperatures increased from 50 to 9$0^{\circ}C$ and extraction times prolonged from 1 to 5 min. The contents of important free sugars such as sucrose and glucose slightly increased as the extraction time was prolonged, while little difference in the content of fructose with the prolonged extraction time. Catechins contents extracted from the commercial steamed green tea were increased at higher temperature and longer extraction time. Epigallocatechin (EGC) extracted from 9$0^{\circ}C$ (extraction time 5 min). presented 99.9 mg/g in highest composition of catechin followed by epigallocatechin gallate (EGCg), epicatechin (EC), epicatechin gallate (ECg). The content of vitamin C extracted from green tea was increased about 2 times as the extraction temperature increased from 50 to 9$0^{\circ}C$ and as the extraction time increased from 1 to 5 min. with exception at 9$0^{\circ}C$(extraction time:5 min) which showed less vitamin C content than 7$0^{\circ}C$(extraction time : 3 min) probably due to possible destruction of vitamin C by high temperature.

• 한국식품영양학회지
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• 제4권1호
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• pp.61-68
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• 1991

In order to study the extraction mechanism of barley tea, some factors affecting extraction and physical properties of roasted barley and extract were examined. The main results of this study are as follows : 1. The roasted barley particles used as the raw materials were amorphous. Under the extraction condition used the average swelling ratio of the particles and imbibed volume were 1. 3g and 1.65ml/g respectively. The maximum soluble solid content in the roasted barley was 67.07%. 2. The concentrations of the barley extracts were determined by measuring their optical densitis at 420nm and the relationship between the concentration(C) and optical density(O. D.) was expressed as : C=6, 178XO. D. As shown in the following relationship, the viscosities(u: Ns/m2) of barley extracts were Influenced by concentration(C : kg/m3) and temperature(T : C). $\mu$=5.6731$\times$$10^{-4}e^{2.7}^{\times10^{{-3}\times{C}}$$\mu$=3.577$\times$$10^{-3}e^{{-3.02}\times{10^{-2}\times{T}}$

• KSBB Journal
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• 제29권1호
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• pp.22-28
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• 2014

In this study, we investigate the effect of pretreatment method on lipid extraction from Enteromorpha intestinalis using physical, thermo-chemical, and enzymatic process such as ultrasonication, high temperature treatment, freezing, microwave irradiation, osmotic shock, pH shock, homogenizing, and enzymatic treatment. In pretreatment with separated lipid extraction, the high extraction yield was obtained by high temperature treatment ($121^{\circ}C$ for 5 min) with 0.1 N HCl, which is 1.4 times higher than that of control. In pretreatment with direct lipid extraction, the high extraction yields were obtained by 0.1 N HCl pretreatment, microwave irradiation (700W, 1 min with twice), and 10% NaCl pretreatment, which is 1.45 times higher than that of control. In the result of enzymatic pretreatment with 17 kinds of enzymes, Cellic CTec II showed the high extraction yield of 5.3%, and which is 1.9 times higher than that of control. Moreover, the extraction yield was increased by the increase of enzyme amounts. In 10% enzyme amount, about 5.8% yield was obtained.

• 분석과학
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• 제19권6호
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• pp.455-459
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• 2006

The extraction and separation of glabridin from licorice root by HPLC was performed in this work. First, by investigating the different extraction solvents, extraction methods and extraction times, a one-hour ultrasonic extraction procedure with ethyl acetate as the extraction solvent was optimized. Then the ethyl acetate extraction was applied to RP-HPLC for separation of glabridin. The column efficiencies and resolutions were experimentally investigated with different mobile phase compositions. Baseline separation of glabridin was obtained under the mobile phase composition of 50/50 vol.% (ACN/water). The retention time of glabridin was 20.3 min. The peak of glabridin was collected from the HPLC elution for several times and identified by LC/MS. Under the optimum extraction and HPLC separation methods, 1.26 g of glabridin per kg licorice root could be extracted.

• 대한화학회지
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• 제42권1호
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• pp.36-41
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• 1998

Co(Ⅱ)와 Cu(Ⅱ)의 금속이온을 디티존의 클로로포름용액으로 추출할 때, 보조 리간드로 티오시안산이온을 사용하여 금속착물의 분포비, 추출률 및 추출속도상수를 구하여 보조 리간드를 사용하지 않았을 경우와 비교하였다. 착물의 분포비는 보조 리간드가 없을 때보 다 보조 리간드가 있을 때, Co(Ⅱ)는 염기성에서 3배 정도, Cu(Ⅱ)는 넓은 pH범위에서 2배 정도 더 크게 나타났고, 추출률은 보조 리간드가 존재하면 Co(Ⅱ)는 90에서 99%로, Cu(Ⅱ)는 95에서 99%로 증가하였다. 그리고 추출속도상수 $k_1\;은\;Co(Ⅱ):1.2{\times}10^5, k_2: 1.34{\times}10^{17} mol^{-1}dm^3s^{-1}$이였으며 Cu(Ⅱ)는$k_1\;과\;k_2$가 각각$1.1{\times}10^8과\;2.83{\times}10^{10} mol^{-1}dm^3s{-1}이였다.

• 한국식품과학회지
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• 제12권2호
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• pp.133-139
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• 1980

미생물 균체로부터 유용 물질을 추출해 내는 기작(機作)을 조사하기 위하여 Rhodotorula rubra YUFE 1526의 냉동 건조 균체로 부터의 균체 유지 추출을 통하여 고찰하였으며, 다음과 같은 결과를 얻었다. 1. 균체 유지의 최적 추출 용매로는 메탈알코홀이 적합하였으며, extractable total lipid의 량은 균체량의 19.17 % 이었다. 2. 교반 속도의 영향은 없었으며, 최적 추출 온도는 $50^{\circ}C$이었고, 2시간 동안의 추출에서 90 %의 추출률을 보였다. 3. 균체 유지의 확산도는 $50^{\circ}C$에서 $9.4{\times}10^{-9}\;mm^2/min.$로서 최대를 보였으며 추출 온도에 따른 확산도는 다음과 같았다. $D=2.2e^{0002907T}{\times}10^{-9}\;mm^{2}/min\;20^{\circ}C{\leq}T{\leq}50^{\circ}C$ 4. 균체내의 유지 함유량이 변화되어도 확산도 값은 $9.4{\times}10^{-9}\;mm^2/min.$로서 거의 일정하였다. 5. 추출 모델의 설정을 통해 구해진 이론식이 실험치와 거의 일치하고 있었다.

• 자원리싸이클링
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• 제22권5호
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• pp.29-34
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• 2013

TEHA와TEHA 및TBP와 LIX63과의 혼합용매를 사용하여 염산용액으로부터 백금과 로듐을 분리하기 위한 용맥추출실험을 수행하였다. 염산농도 1-9 M 범위에서 추출제의 농도에 따른 두 금속의 추출거동과 분리 가능성을 조사하였다. 혼합용액에서 백금과 로듐의 농도는 각각 $1{\times}10^{-3}M$과 $2{\times}10^{-4}M$로 조절하였다. TEHA와 혼합추출제에 의한 추출시 로듐의 추출율은 추출조건에 의존하나, 백금은 염산농도와 무관하게 모두 추출되었다. 혼합용액에서 염산농도가 낮을 경우 로듐이 추출되지 않아 백금과 로듐의 분리가 가능하였다. LIX63을 첨가한 TEHA는 로듐의 추출율을 향상시켰으나, TBP를 첨가한 TEHA는 두 금속의 추출에 거의 영향을 미치지 않았다.

• 대한약침학회지
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• 제15권2호
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• pp.24-30
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• 2012

This study compared Ojeok-san (Wuji-san in Chinese) decoctions produced using different extraction methods for variable times. Decoctions were extracted in pressurized or non-pressurized conditions for 60, 120, and 180 mins. We investigated the Ojeok-san extract yield, the total soluble solid content, the hydrogen ion concentration (pH), and the reference compound content. The extract yield and the total soluble solid content were higher in decoctions produced by non-pressurized extraction; both were proportional to the extraction time. The pH tended to decrease as the extraction time was increased in decoctions produced using both methods. After 60 and 180 mins, the levels of albiflorin, paeoniflorin, nodakenin, naringin, and neohesperidin were significantly higher in decoctions extracted using the non-pressurized method compared with those extracted using the pressurized method. After 120 mins, only cinnamaldehyde was extracted in a greater amount in pressurized decoctions compared with non-pressurized decoctions. The levels of paeoniflorin, ferulic acid, nodakenin, naringin, hesperidin, neohesperidin, and glycyrrhizin increased with time in non-pressurized decoctions. This study showed that the use of pressurized and non-pressurized extraction methods for different times affected the composition of Ojeoksan (Wuji-san) decoctions.

• 한국식생활문화학회지
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• 제28권3호
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• pp.320-327
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• 2013

The quality characteristics of Omija (Schizandra chinesis Baillon) extracts under various extraction temperatures and times were examined. The pH level of the extracts ranged from 3.35-3.47. The sugar and solid content of the samples significantly increased with increasing extraction temperatures and times (p<0.01). In contrast, the lightness of the extracts decreased with increasing extraction temperatures and times (p<0.001). In a palatability test, extracts boiled at $80^{\circ}C$ for 30 minutes scored high in terms of color, flavor, turbidity, sourness, and overall acceptability. Hydroxy radical scavenging activity and polyphenol content of the extracts significantly increased with increasing extraction temperatures and times (p<0.01). Furthermore, direct correlations between hydroxy radical scavenging activity and polyphenol content (or flavonoid content) were established through simple regression (r>0.9) for different extraction temperatures and times. From these results, extracts boiled at $80^{\circ}C$ for 120 minutes is the best to product omija beverage considering functionality and sensory evaluation as well.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.298-301
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• 2000

Heavy metals are extracted from stream sediments, roadside soils and sediments and soils and tailings from mining area using partial extraction, acid digestion and HF-digestion. Compared to amounts of heavy metals extracted using partial extraction, those extracted using acid digestion are higher by 2.0∼220.9 times in Cu, 2.4∼2806.1 times in Pb, 1.3∼121 times in Cd, 14.1∼1300885 times in Fe, 1.2∼271.5 times in Mn, 1.3∼372.5 times in Zn, 2.2∼1734.5 times in Cr. Although partial extraction, which extracts less amounts of heavy metals from soil compared to acid digestion, is used in domestic standard method for examination of soil, domestic soil standard for heavy metals in non-agricultural and industrial areas is higher than soil standard in foreign countries which use acid digestion, For improvement of the domestic standard method for assessment of soil, it is suggested to lower the domestic soil standard for heavy metals or to change pretreatment method for extracting heavy metals from partial extraction to acid digestion with modifying the soil standard.