• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
• /
• pp.669-675
• /
• 1991

Based on process analysis as well as extensive operation experience, two fuzzy expert control algorithms, for startup and control, are proposed for a supercritical fluid extraction process which has high interacting multivariable structure. In the proposed algorithms, a new simple defuzzification method which only requires four fundamental arithmetic rules is also presented. Through numerical simulations, control performance using the proposed control algorithm is compared with that of a different fuzzy algorithm by an other researcher and that of conventional PID-type controllers which are tuned by well-known optimal criteria. Also, the proposed control algorithm has been tested to the bench scale supercritical fluid extraction process. As a consequence, the proposed fuzzy expert controller has shown fast and robust control performance while the other controllers show sluggish and/or highly oscillatory responses.

• 한국해양바이오학회지
• /
• 제1권3호
• /
• pp.206-212
• /
• 2006

Supercritical carbon dioxide ($SCO_2$) extraction was investigated as a method for protein-sourcing material from squid viscera. To find the optimum conditions, the extraction of squid viscera using $SCO_2$ was performed under the conditions of temperature range from 35 to $45^{\circ}C$ and constant pressure 25 MPa using Hewlett-Packard 7680T. Also from result of SDS-PAGE, the protein denaturation was minimized when using $SCO_2$ extraction. And the major amino acids in the squid viscera were glutamic acid, aspartic acid, lysine, leucine, arginine, alanine, glycine, isoleucine, and valine. The main fatty acids from squid viscera were myristic acid, palmitic acid, stearic acid, heneicosanoic acid, palmitoleic acid, elaidic acid, oleic acid, eicosenoic acid, EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid).

• Journal of Acupuncture Research
• /
• 제28권2호
• /
• pp.89-95
• /
• 2011

Objectives : The purpose of this study was to investigate the composition of Rehmannia glutinosa's essential oils with Rehmanniae Radix herbal acupuncture Methods : I obtained the essential oils of Rehmannia Radix by hydrodistillation extraction method and supercritical fluid extraction(SFE) method, and then I analyzed those by GC/MS(gas chromatography/mass spectrum). Results : 1. With GC(gas chromatography) and GC/MS(gas chromatography/mass spectrum) analysis. I identified 9 compounds in the Rehmanniae Radix's essential oil obtained through the SFE method. The main compounds were as follows : Hexachloroethane(2.24%), N-Butyl-benzenesulfonamide(2.05%), hexadecanoic acid(1.93%), hexadecanoic acid, ethyl ester(3.49%), 9,12-Octadecadienoic acid(z,z)(2.70%), (9E)-9-Octadecenoic acid(6.14%), ethyl linoleate(4.43%), ethyl oleate(5.80%). 2. I failed to get Rehmanniae Radix's essential oil obtained through the hydrodistillation method. 3. With GC(gas chromatography) and GC/MS(gas chromatography/mass spectrum) analysis. I identified 4 compounds in the Rehmanniae Radix's essential oil obtained through the hydrodistillation method. The main compounds were as follows : Ethylbis(trimethylsilyl)amine(1.04%), 2-(Trimethylsiloxy)benzoic methyl ester(2.65%), Hexadecanoic acid trimethylsilyl ester(12.61%), octadecanoic acid, trimethylsilyl ester(6.28%). Conclusions : The substances by hydrodistillation method may not perfectly match with the substances by supercritical fluid extraction(SFE) method in essential oils extracted form Rehmanniae Radix. But, the main substances was assumed Hexadecanoic acid and octadecanoic acid.

• 대한약침학회지
• /
• 제11권1호
• /
• pp.177-187
• /
• 2008

Objectives : This study was performed to analyze the effective components of essential oil obtained from Yongdamsagantang, which has been efficacious against leukorrhea in gynecologic diseases. Methods : I obtained the essential oils of Yongdamsagan-tang by hydrodistillation extraction method and supercritical fluid extraction(SFE) method, and then I analyzed those by GC/MS(Gas Chromatography/Mass Spectrum). Results : 1. The optimum SFE(Supercritical Fluid Extraction) condition was obtained in the following experiment conditions: pressure 200atm, temperature $45^{\circ}C$, duration of extraction 25minutes. 2. With GC(Gas Chromatography) and GC/MS(Gas Chromato- graphy/Mass Spectrum) analysis, I identified 37 compounds in the Yongdamsagan-tang's essential oil obtained through the SFE method. The main compounds were as follows : 3-Methyl-but-2-enoic acid,2,2-dimethyl-8-oxo-3,4-dihydro-2H,8H -pyrano[3,2-g]chromen-3-yl ester(49.81%), (Z)-6-Pentadecen-1 -ol(3.19%), (-)-Spathulenol(2.40%). 3. I identified 4 compounds in the Yongdamsagan-tang's essential oil obtained through the hydrodistillation method. The main compounds were as follows : 3-Methyl-but-2-enoic acid, 2,2-dimethyl-8-oxo-3,4-dihydro-2H,8H-pyrano [3,2-g]chromen-3-yl ester(2.61%). 4. 3-Methy I-but-2-enoic acid, 2,2-dimethyl-8-oxo-3,4-dihydro-2H,8H-pyrano[3,2-g] chromen-3-yl ester, all were identified in both the SFE method and the hydrodistillation method, but the others were not identified in common. 5. I also conducted an additional test in order to examine the essential oil's antimicrobial action against bacteria. Both MIC(Minimum Inhibitory Concentrations) and MBC(Minimum Bactericidal Concentrations) were $0.125mg/m{\ell}$ against N. meningitidis, however MIC and MBC were $1.0mg/m{\ell}$ in antimicrobial action against 12 different genera of bacteria.

• Food Science and Biotechnology
• /
• 제17권3호
• /
• pp.470-474
• /
• 2008

The whole berry, pulp, and seed of sea buckthorn fruit were extracted with supercritical $CO_2$ to produce edible oils. The effects of extraction pressure, temperature, and $CO_2$ flow rate on the oil yield and extraction rate were investigated, and the fatty acid composition, tocopherol, and carotenoid contents of the oils were compared. The results showed that the extraction rate was affected by pressure, temperature, and $CO_2$ flow rate and, in general, the yield increased with a rise in any of the 3 variables. Fatty acids in the whole berry and pulp oil were dominated by monounsaturated fatty acids (>64%), followed by saturated fatty acids (about 30%). In contrast, fatty acids in the seed oil consisted mainly of polyunsaturated (>60%) and monounsaturated fatty acids (>24%). The seed oil had a slightly higher content of tocopherols, but a much lower content of carotenoids, compared with the whole berry or pulp oil.

• 한국환경농학회지
• /
• 제27권4호
• /
• pp.447-455
• /
• 2008

Recombinant yeast estrogenicity (YES) assay was used as a bioanalytical tool in order to screen $17{\beta}$-estradiol in the soil samples collected from different sites of South Korea. Solvent extraction and supercritical fluid extraction (SFE) methods were compared for the extraction of the estradiol from the soils. Most high detection of the estradiol based on YES assay was observed in the soils extracted with methanol. Different types of estrogenic hormones including $17{\beta}$-estradiol were suggested to be possibly exiting in the soils, since the methanol extracts of the soils showed an estrogenic activity that was not observed in the hexane extracts of the soil. SFE extracts showed estrogenic activity in some of the samples but methanol extract showed best activity.

• KSBB Journal
• /
• 제25권5호
• /
• pp.437-442
• /
• 2010

본 연구에서는 초임계 이산화탄소의 추출기술에 초음파 적용을 위한 기초 연구로서 캐놀라 씨앗의 입자의 크기, $CO_2$ 유속, 추출기의 종횡비, 초음파 파워 등의 공정변수가 캐놀라 오일의 추출 속도와 수율에 미치는 영향에 대하여 조사하였다. 초임계 이산화탄소 추출에 있어 씨앗을 더 작게 분쇄할수록 더 빠른 추출속도를 보였으며, 추출기의 종횡비가 감소할수록, $CO_2$의 유속이 증가할수록 추출 속도는 증가하였다. 그러나 초음파가 적용된 초임계 이산화탄소 추출의 경우 0.6 mm 이하로 분쇄된 씨앗의 입자 크기 분포가 가장 큰 시료 C의 경우 입자들의 뭉침 현상 증가로 인해 오히려 초음파의 적용이 추출속도와 수율을 크게 감소시켰으며, 12.0 L/min의 $CO_2$ 유속에서도 추출 속도와 수율이 감소하는 것을 확인하였다. 초음파의 적용은 초기 추출시간 50-70분 동안 추출속도 증가에 거의 영향을 미치지 않았으며, 초음파 파워 또한 추출 속도와 수율의 증가에 큰 영향을 미치지 않음을 확인할 수 있었다.

• KSBB Journal
• /
• 제16권1호
• /
• pp.66-70
• /
• 2001

순수한 초임계 이산화탄소를 이용하여 camptothecin(CPT)와 10-hydroxy camptothecin(HCPT) 추출 시험을 결과, 이들은 각각 유기용매 메탄올 추출에 비교하여 3%와 2% 밖에 추출되지 않았다. 보조용매로 메탄올과 에탄올을 이용하여 CPT와 HCPT를 추출하면 추출 효율이 상승됨을 확인할 수 있었다. 특히 에탄올 보다 메탄올이 효율이 좋았다. 따라서 보조용매 적용에 관련된 여러 조건들을 최적화 하였다. 메탄올을 보조용매로 사용하는 경우에 보조용매의 농도가 증가할수록 추출 효율도 증가하였고 16% 이상에서는 추출 효율이 완만하게 증가하였다. 또한 추출은 온도에 따라 크게 영향을 받지 않아으나 온도에 따라 약간 증가하는 경향을 보였다. 초임계 추출에서 압력의 영향을 살펴본 결과 250 bar까지 압력이 증가할수록 추출 효율은 증가하였다. Acetate ion을 공급하여 추출 실험을 수행하였으나 CPT나 HCPT 모두 ion pairing agent의 영향은 없었다. 본 시스템과 같은 solid/fluid 추출 시스템에서 추출 효율에 영향을 크게 미치는 3가지 요소 (용해도, 확산, 및 matrix)중 확산의 영향을 살펴보았다. 여러 기하학적 모델 중 matrix가 구형인 hot-ball model로 확산게수를 계산하였다. 본 시스템에서 보조용매를 포함한 초임계 유체의 $D/r^2$ 값은 0.0072 $min^{-1}$로서 순수한 메탄올 유기용매 추출보다 큰 값을 보였다.

• 생명과학회지
• /
• 제13권5호
• /
• pp.569-575
• /
• 2003

초임계 이산화탄소를 이용하여 saw palmitto로부터 전립선 비대증 치료를 위한 유효성분을 효율적으로 추출하기 위하여 초임계 유체의 압력(22, 30 Mpa), 온도 $(35^{\circ}C,\; 60^<\circ}C)$, 및 보조용매의 농도, 및 추출시간에 다른 효율을 조사하였다. 보조 용매로는 메탄올보다는 에탄올이 효과적이었고. 보조용매의 농도가 증가할수록 유효성의 추출 효율은 증가하였고 15% 에탄올 농도에서 효율이 가장 높았다. 15%에탄올 농도에서 초임계유체의 최적 추출조건은 압력은 30 Mpa, 온도는$60^<\circ}C$이였고, 추출시간에 따른 추출효율은 추출시간이 증가할수록 완만하게 증가하는 경향을 나타내었다. 초임계 이산화탄소의 추출조건으로 saw palmitto로부터 전립선 비대 치료를 위한 유효물질을 추출할 수 있다.

• Korean Journal of Acupuncture
• /
• 제37권2호
• /
• pp.88-96
• /
• 2020

Objectives : The purpose of this study was to investigate the anti-oxidant and anti-aging effect of the seed of Euphorbia lathyris L. extracted by supercritical CO₂. Methods : Human dermal fibroblast cells dosed with the extract from Euphorbia lathyris L. were harvested and the intracellular proteome was analyzed to examine the expression of proteins related collagen synthesis pathway, metalloproteinases (MMPs), extracellular matrix (ECM)-cell interaction, cytokines, and antioxidant enzymes by 2-dimensional gel electrophoresis. Results : Fatty acid analysis of the extract from Euphorbia lathyris L. showed oleic acid was 84% and linoleic acid was 4.1%. Antioxidative effect was about 53% by beta carotene bleaching assay. In 2-dimensional polyacrylamide gel electrophoresis (2-D PAGE) analysis, fifteen protein changes in five mechanisms which were collagen synthesis pathway, MMPs, ECM-cell interaction, cytokines, and antioxidant enzymes were analyzed. Conclusions : This study suggests the supercritical extraction from the seed of Euphorbia lathyris L. could be used as anti-oxidant substances for pharmacopuncture.