• 한국식품과학회지
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• 제8권4호
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• pp.242-246
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• 1976

Rhizopus japonicus의 정제(精製) lipase의 특성(特性)을 검토(檢討)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 정제(精製) lipase의 작용최적(作用最適) PH는 6.8, 안정(安定) PH 범위(範圍)는 $5.0{\sim}8.0$, 최적온도(最適溫度)는 $35^{\circ}C$이고, $45^{\circ}C$이하(以下)에서 안정(安定)하였으며 그 이상(以上)의 온도(溫度)에서는 급격(急激)하게 불활성화(不活性化) 되었다. 2. 정제(精製) lipase는 coconut oil, castor oil 및 palm oil을 가장 잘 분해(分解)시켰다. olive oil, 및 soybean oil에서는 분해율(分解率)이 약간 떨어지며, Tween 80에서는 분해율(分解率)이 coconut oil의 30% 정도(程度) 밖에 되지 않았다. 3. 정제(精製) lipase는 $Ca^{++}$, $Mg^{++}$에 의(依)하여 현저(顯著)하게 활성화(活性化)되었으며, $Hg^{++}$ $Fe^{+++}$에 의(依)하여는 심(甚)하게 저해(沮害)되었다.

• 한국식품영양과학회지
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• 제23권1호
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• pp.23-30
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• 1994

This study was carried out to investigate the effect of the feeding mixture of linseed oil, rich in n-3 PUFA and the sunflower seed oil, rich in n-6 PUFA on the lipid metabolism in the dietary hyperlipidemic rats. After male Sprague-Dawley rats were induced hyperlipidemia by feeding the diet containing lard, butter and cholesterol for 3 weeks, then they were fed with the diet containing lard 3.0 % and butter 12.0% for control, the mixture in different proportion of both linseed oil and sunflower seed oil and antihyperlipidemic drugs for 2 weeks. Analysis of the lipid component of the serum showed following results. Concentration of total cholesterol in serum was significantly lower in the other groups except group 2 (lard 3.0 % + olive oil 12.0%) than in the control group , especially in groups 3 (cholestyramine 2.0%) and 5 (lard 3.0% + linseed oil 12.0%). HDL-C and the ratio of HDL-C to total cholesterol concentration were higher in groups 1, 3, 5 and 9 (lard 3.0% + sunflower seed oil 12.0%) , while the atherosclerotic index was low in groups3, 5. Concentrations of free cholesterol and choesteryl ester in serum were significantly lower in the other groups except group 2 than in the control group, especially lower in grop 5. Concentration of LDL was significantly higher in group 2 while it was remarkably lower in groups 3 and 5, while those of triglyceride in groups in 3 and 4 (lipraroid) were significantly higher than in the control groups. From the data on concentration of total choelsterol , HDL-cholesterol, LDL, phospholipid and triglyceride in serum, the results suggested that the feeding mixed with 3.0% lard and 12.0% linseed oil or 2.0% cholestyramine were most effective for the improvement of the serum lipids.

• Journal of Electrical Engineering and Technology
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• 제13권2호
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• pp.902-910
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• 2018

In recent times, development of nanofluid insulation for power transformers is a hot research topic. Many researchers reported the enhancement in dielectric characteristics of nano modified mineral oils. Considering the drawbacks of petroleum based mineral oil, it is necessary to understand the dielectric characteristics of nanofluids developed with natural ester based oils. Palm oil has better insulation characteristics comparable to mineral oil. However very few research reports is available in the area of nanofluids based on palm oil. Partial discharge (PD) is one of the major sources of insulation performance degradation of transformer oil. It is essential to understand the partial discharge(PD) characteristics by collecting huge data base of PD performance of nano modified palm oil which will increase its confidence level for power transformer application. Knowing these facts, in the present work, certain laboratory experiments have been performed on PD characteristics of nano $SiO_2$ modified palm oil at different electrode configurations. Influence of concentration of nano filler material on the PD characteristics is also studied. Partial discharge inception voltage, Phase resolved partial discharge (PRPD) pattern, PD signal time-frequency domain characteristics, PD signal equivalent timelength-bandwidth mapping, Weibull distribution statistical parameters of PRPD pattern, skewness, repetition rate and phase angle variations are evaluated at different test conditions. From the results of the experiments conducted, we came to understand that PD performance of palm oil is considerably enhanced with the addition of $nano-SiO_2$ filler at 0.01%wt and 0.05%wt concentration. Significant reduction in PD inception voltage, repetition rate, Weibull shape parameter and PD magnitude are noticed with addition of $SiO_2$ nanofillers in palm oil. These results will be useful for recommending nano modified palm oil for power transformer applications.

• KSBB Journal
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• 제28권2호
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• pp.115-122
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• 2013

Volatile flavor compounds of Chamaecyparis obtuse essential oil were extracted by simultaneous steam distillation extraction (SDE) and supercritical fluid extraction (SFE) and analyzed by GC-MS. A total of 48 and 50 components were identified in essential oil by SDE and SFE, respectively. Monoterpenes, oxygenated monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and diterpenes in essential oil by SDE were 37.24, 10.9, 9.61, 0.22, and 0.22%, respectively. In the case of SFE, they were 19.1, 23.3, 22.66, 1.31, and 10.57%, respectively. Antioxidant activities were increased with the increase of essential oil up to $80{\mu}L/mL$, irrespective of extraction method. Especially, when the essential oil concentration extracted by SDE was increased from 20 to $80{\mu}L/mL$, the antioxidant activity was increased from 10.5 to 55.1%. However, over $80{\mu}L/mL$ of essential oil, an equilibrium state was maintained. In the case of essential oil extracted by SFE, it was decreased compared to that of SDE. For the improvement of atopic dermatitis, various cosmetics such as an ato-cide soap, ato-cide spray, and ato-cide lotion containing essential oil extracted by SFE were tested. About over 90% was useful for the improvement of atopic dermatitis after 4 weeks of clinical trial targeting 40 female adults. These results demonstrate that ato-cide soap, ato-cide spray, and ato-cide lotion containing essential oil extracted by SFE could be used in functional cosmetics.

• 설비공학논문집
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• 제18권3호
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• pp.254-261
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• 2006

The effect of enhanced geometry (pore diameter, gap width) is investigated on the pool boiling of R-123/oil mixture for the enhanced tubes having pores with connecting gaps. Tubes with different pore diameters (and corresponding gap widths) are specially made. Significant heat transfer degradation by oil is observed for the present enhanced tubes. At 5% oil concentration, the degradation is 26 to 49% for $T_{sat}=4.4^{\circ}C$. The degradation increases 50 to 67% for $T_{sat}=26.7^{\circ}C$. The heat transfer degradation is significant even with small amount of oil (20 to 38% degradation at 1% oil concentration for $T_{sat}=4.4^{\circ}C$), probably due to the accumulation of oil in sub-tunnels. The pore size (or gap width) has a significant effect on the heat transfer degradation. The maximum degradation is observed for $d_p$ = 0.20 mm tube at $T_{sat}=4.4^{\circ}C$, and for $d_p$=0.23 mm tube at $T_{sat}=26.7^{\circ}C$. The minimum degradation is observed for $d_p$=0.27 mm tube for both saturation temperatures. It appears that the oil removal is facilitated for the larger pore diameter (along with larger gap) tube. The highest heat transfer coefficient with oil is obtained for $d_p$ =0.23 mm tube, which yielded the highest heat transfer coefficient for pure R-123. The heat transfer degradation increases as the heat flux decreases.

• 미생물학회지
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• 제33권2호
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• pp.157-162
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• 1997

최근 유류에 오염된 환경을 회복시키기 위하여 생물정화 방법이 널리 이용되고 있다. 따라서 유류오염 환경을 처리하기 위한 생물정화용 생물제제가 보편화되면서 외국으로부터 많은 제품이 국내로 유입되고 있다. 그러나 국내에는 이와 같은 제품의 규격기준이나 표준 실험방법이 체계화되어 있지 않고 또한 효용성에 대한 실제 실험결과가 없는 상태이다. 그러므로 본 실험에서는 일부 유류처리용 생물제제 5종을 대상으로 유류분해율에 대한 실험을 수행하였다. 실험결과 대부분의 제품들은 함유된 화학유분산제에 의해 유류분산능을 나타내었고 유류분해율은 매우 낮은 것으로 나타났다. 일부제품(D)의 경우에는 해수에 분포되어 있는 토착 유류분해세균의 유류분해도를 오히려 저해하는 결과를 나타내었다. 이와 같은 실험의 결과로 미루어 향후 생물정화용 제제의 규격기준 및 표준 실험방법을 국내에도 확립할 필요가 있고, 그러므로서 효율적인 생물정화 기술방법 사용이 활성화될 수 있을 것이다.

• KSBB Journal
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• 제10권5호
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• pp.582-588
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• 1995

해양의 유류유출이 잦은 지역으로부터 crude oil 분해능이 뛰어난 미생물을 분리하여 통정한 결과 Pseudomoans 속으로 판명되였으며, 이를 Pseud$\sigma$ moans sp. CHCS-2로 명 명하였다. 이 균주가 배양 중에 생산하는 biosurf actant의 생생 최적 pH 및 NaCI 농도는 각각 8.0 및 3.0% 였으며, 질소원인 peptone에 영향을 받았다. 2% Kuwait crude oil이 첨가된 배양액을 48, 96, 132시간별로 gas chroma­t tography를 이용, 잔류 oil을 분석한 결과 Kuwait crude oil의 C10-CI4부위에 biosurf actant가 작용하여 분해하였으며, 배양 상층액으로부터 Amberlite XAD-7을 이용한 흡착 chromatography와 Sepha­d dex G-100을 이용한 gel chromatography, 그리고 HPLC를 이용하여 biosurf actant를 분리. 정제한 결과 유화력이 뛰어난 단일 peak를 얻었다. Bio-sur­f f actant 유화력은 $40^{\circ}C$에서 가장 좋았으며, 안정성 은 $30^{\circ}C$에서 $60^{\circ}C$까지의 넓은 온도 범위에서 유지 되었다. 또한, 정제된 biosurf actant를 이용하여 계 연장력에 미치는 영향을 검토한 결과, 상엽적으로 널리 판매되고 있는 Tween 80, Tween 60 그리고 SDS보다 표연장력 저하능력이 뛰어난 것으로 밝혀졌다.

• 한국미생물·생명공학회지
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• 제48권2호
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• pp.148-157
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• 2020

Eucalyptus oil is a rich source of bioactive compounds with a variety of biological activities and is widely used in traditional medicine. Eucalyptus citriodora is cultivated for the production of essential oils. However, the mode of antibacterial action of essential oils from E. citriodora is not well-known. This study aimed to determine the chemical components, microbial inhibitory effect, and mechanism of action of the essential oil from E. citriodora. The oil was extracted from E. citriodora leaves by hydro-distillation and the chemical components were analyzed using gas chromatography-mass spectrometry. The antibacterial activities of eucalyptus oil against gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, and Staphylococcus intermedius) and gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) were screened by disc diffusion method and quantitative analysis was conducted by the microdilution method. The mechanism of action of the extracted essential oil was observed using SEM and analyzed by SDS-PAGE. The major components of E. citriodora oil were citronellal (60.55 ± 0.07%), followed by dl-isopulegol (10.57 ± 0.02%) and citronellol (9.04 ± 0.03%). The antibacterial screening indicated that E. citriodora oil exhibited prominent activity against all tested strains. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against B. subtilis were 0.5% and 1.0%, respectively. The MIC and MBC concentrations against S. aureus, S. intermedius, E. coli, and P. aeruginosa were 1% and 2%, respectively. As observed by SEM, the antibacterial mechanism of E. citriodora oil involved cell wall damage; SDS-PAGE revealed decrease in protein bands compared to untreated bacteria. Thus, E. citriodora oil showed significant antimicrobial properties and caused cellular damage.

• 한국식품과학회지
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• 제34권6호
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• pp.984-991
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• 2002

순수 참기름과 채종유, 옥수수유, 대두유를 10%, 30%, 50%씩 첨가한 참기름 혼합유를 제조하여 $60^{\circ}C$의 incubator에서 8주간 저장하면서 혼합유의 산화 안정성과 향기 성분의 변화 그리고 관능 검사를 실시하였다. 모든 시료의 POV는 저장 6주에 최고값을 나타내었으며 채종유와 옥수수유 10%, 30%, 50%씩 그리고 대두유 10%를 첨가한 참기름 혼합유는 순수 참기름 보다 저장 기간 동안 과산화물 생성이 억제되어지는 효과가 있음을 나타났다. 산패 유도기간도 채종유와 옥수수유 10%, 30%, 50%씩 그리도 대두유 10%를 첨가한 참기름 혼합유에서는 대조구인 참기름 보다 그 기간이 더 연장되었다. 상대적 항산화 효과(Relative Antioxidant Effectiveness: RAE)는 10% 채종유를 첨가한 혼합유가 순수한 참기름 보다 6배의 효과가 있었다. 그리고 산가는 모든 혼합유 시료가 참기름 보다 더 낮은 결과를 나타내었으나 단일 식물성유 보다는 그 수치가 높았다. 혼합유의 향기 성분은 참기름에서 확인된 참기름의 독특한 방향을 나타내는 pyrazine류가 참기름 혼합유에서도 확인되었으며 저장 기간이 연장됨에 따라 모든 시료에서 산패의 지표가 되는 aldehyde, ketone, acid등의 carbonyl 화합물의 함량이 증가되었다. 관능평가에서는 10%의 채종유, 옥수수유, 대두유를 첨가한 참기름 혼합유 시료는 대조구인 순수 참기름과 유의적인 차이가 없는 것으로 밝혀졌다. 이와 같은 결과로 미루어 볼 때 참기름과 식물성유의 혼합은 매우 바람직하며 단일 식물성유보다 산화 안정성이 크게 증대되었을 뿐 아니라 관능적인 품질에도 차이가 없으므로 경제적인 면에서도 매우 유용할 것으로 생각된다.

• Journal of Ginseng Research
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• 제37권4호
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• pp.468-474
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• 2013

Ginseng seed oil was prepared using compressed, solvent, and supercritical fluid extraction methods of ginseng seeds, and the extraction yield, color, phenolic compounds, fatty acid contents, and phytosterol contents of the ginseng seed oil were analyzed. Yields were different depending on the roasting pretreatment and extraction method. Among the extraction methods, the yield of ginseng seed oil from supercritical fluid extraction under the conditions of 500 bar and $65^{\circ}C$ was the highest, at 17.48%. Color was not different based on the extraction method, but the b-value increased as the roasting time for compression extraction was increased. The b-values of ginseng seed oil following supercritical fluid extraction were 3.54 to 15.6 and those following compression extraction after roasting treatment at $200^{\circ}C$ for 30 min, were 20.49, which was the highest value. The result of the phenolic compounds composition showed the presence of gentisic acid, vanillic acid, ferulic acid, and cinnamic acid in the ginseng seed oil. No differences were detected in phenolic acid levels in ginseng seed oil extracted by compression extraction or solvent extraction, but vanillic acid tended to decrease as extraction pressure and temperature were increased for seed oil extracted by a supercritical fluid extraction method. The fatty acid composition of ginseng seed oil was not different based on the extraction method, and unsaturated fatty acids were >90% of all fatty acids, among which, oleic acid was the highest at 80%. Phytosterol analysis showed that ${\beta}$-sitosterol and stigmasterol were detected. The phytosterol content of ginseng seed oil following supercritical fluid extraction was 100.4 to 135.5 mg/100 g, and the phytosterol content following compression extraction and solvent extraction was 71.8 to 80.9 mg/100 g.