• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.345-349
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• 2000

To easily separate chitosanoligosaccharides by size exclusion, an coencapsulating technology of substrate and enzyme was developed. The membrane was composed of alginate and a divalent cation such as calcium. Chitosan and chitosanase were enveloped in this membrane and the product released to medium by size exclusion. The capsule was stabilized in a 2% acetic acid solution (pH 5.0) containing 0.145 M CaCO$_3$. The leakage of substrate caused by the agitation speed was controlled by increasing alginate and CaCO$_3$concentrations. The lower limit of the alginate concentration and the agitation speed were 0.5% and 49rpm, respectively. Membrane thickness and capsule diameter were 10$\mu\textrm{m}$ and 2.5mm, respectively. By TLC analysis, the composition of chitosanoligosaccharides were mainly 3-6 mers. The molecular weight distribution of the released oligosaccharides ranged from 262 to 3624 Da by GPC.

• YAKHAK HOEJI
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• v.42 no.6
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• pp.552-557
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• 1998

Acyl CoA synthetase inhibitor, was purified from the culture broth of a Bacillus sp. B-6, which had been isolated from soil, by chloroform extract, silica gel column chro matography and preparative TLC. The purified acyl CoA synthetase inhibitor showed higher Antifungal activity against C. al-bicans (MIC: 8${\mu}$g/ml). Though the analysis of UV spectrum, melting point, IR spectrum, Mass-spectrum, $^1H$-NMR and $^{13}C$-NMR spectrum, the inhibitor could be identified as phenazine-l-carboxylic acid.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.11a
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• pp.723-734
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• 2017

최근 4차 산업혁명이 많은 관심이 불러일으키며 기술발전의 속도가 점점 빨라지고 있다는 것에 많은 전문가들이 동의하고 있다. 하지만 정량적 데이터로 이를 증명한 논문은 찾기 어렵다. 최근 연구결과를 보면 오히려 일반적으로 기술발전 속도에 반비례한다고 알려진 TCT값이 과거에 비해 점점 커지고 있음을 확인할 수 있다. 실제로 사업화가 되어 산업에 영향을 미치는 특허는 매우 소수이기 때문에, 실제 산업발전에 기여 할 것으로 예상되는 핵심특허만 뽑아 분석하면 특허 전수를 분석한 것과는 다른 양상이 나올 것으로 가정하고 이들의 기술수명주기를 전체 특허의 기술수명기기와 비교하였다.

• YAKHAK HOEJI
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• v.39 no.3
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• pp.306-313
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• 1995

The aim of the present study was to produce low molecular weight cathepsin B inhibitor. A strain of Streptomyces aburabiensis isolated from soil in Korea was selected and the optimum condition for the production of the inhibitor was evaluated. Glucose and soytone were selected as best carbon and nitrogen sources, respectively. From the kinetic analysis in batch fermentation, it was found that the specific cathepsin B inhibitor production rate (q$_{p}$) was linearly related to specific growh rate ($\mu$). The inhibitor in culture filtrate was purified by adsorption on activated charcoal, butanot extraction, silica gel chromatography, ion exchange chromatography using Dowex-1 (Cl form) and Amberlite IRC-50 (H$^{+}$ form), and preparative TLC. From the UV, IR, Mass spectroscopy and $^{1}$H-NMR, the inhibitor was thought to be a new inhibitor of which molecular weight was 199.

• The Journal of Internal Korean Medicine
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• v.24 no.2
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• pp.269-282
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• 2003

Water and ethanol extracts of 67 species of medicinal plants were tested to determine antimicrobial activity against Helicobacter pylori. Among them, the extracts of Coptis japonica showed the best antibacterial activity. The extract of C. japonica showed four major spots on TLC plate and the Rf values of the spots were 0.07, 0.13, 0.21 and 0.73, respectively. Except for the spot of Rf 0.73, other three spots inhibited the cell growth of H. pylori. As shown in HPLC analysis, three antimicrobial spots contain berberine, major antimicrobial substance of C. japonica. However, the spot of Rf 0.13 had higher activity than berberine. The concentrated water extract of three prescribed medicines related with C. japonica showed good antibacterial activity against H. pylori.

• Korean Journal of Pharmacognosy
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• v.20 no.3
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• pp.162-169
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• 1989

Tissue culture of the roots of Panax ginseng was carried out to enhance the production of ginseng callus as well as to increase its contents of ginsenosides. A long cylinder type callus mass was formed when cultured IK callus by rotary shaking culture method, the growth ratio of the callus being 7.71 which was approximately 4 fold higher than those obtained by other culture methods. Ginsenosides $Rg_1$, Re and $Rb_1$ could be detected from the callus mass by TLC, however, their total contents were revealed to be approximately 9% compared to that of the fresh ginseng root equivalent by HPLC analysis,.

• The Korean Journal of Food And Nutrition
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• v.6 no.4
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• pp.322-328
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• 1993

A study of general characteristics of acetone extracted pigment from the cell mass of Rhodospirillum rusrum DSM 467 was carried out for the development of natural food colorant. Through visible absorption scanning, it showed seven absorption peaks at 355, 410, 529, 624, 680 and 747nm, and it was shown to be yellow color. In acidic and neutral conditions, the color was yellow, while in the alkaline condition it was greenish yellow. This pigment was stable at pH range between 3.0~10.0, and below 4$0^{\circ}C$. In the presence of light and oxygen, the stability of pigment rapidly degraded and it became unstable in the presence of metal ions such as Cu2+, Al3+ and Fe3+. Through TLC analysis, it was shown to be composed of seven color fractions.

• Korean Journal of Pharmacognosy
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• v.51 no.4
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• pp.255-263
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• 2020

Ginsenosides are considered to be the most important ingredients in ginseng. They are chemically converted by endogenous organic acids contained in ginseng and the heat applied during red ginseng processing. During this procedure, various converted ginsenosides are produced through hydrolysis of substitute sugars of ginsenosides and forming double bonds through dehydration in the dammarane skeleton. In order to study the conversion mechanism of protopanaxadiol-type ginsenosides during the heat treatment process of ginseng, we purified the three final converted ginsenosides by heating fresh ginseng for a long time. The three isolated ginsenosides were identified as 25(OH)-ginsenoside Rg5, 25(OH)-ginsenoside Rz1 and 25(OH)-ginsenoside Rg3 through NMR spectrum analysis. As a result of quantification of ginseng heated at 100 ℃ for 0 to 6 days by HPLC/UV and TLC methods, the content of 25(OH)-ginsenosides tended to increase in proportion to the time exposed to heat. In particular, the content of 25(OH)-ginsenosid Rg5 was confirmed to be noticeably increased.

• Journal of Life Science
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• v.5 no.4
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• pp.181-189
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• 1995

Carotenoids liberated from the red carotenoprotein from the skin of ascidian(Halocynthia roretzi)were developed on TLC, and two bands were obtained with different Rfvalues. Their chemical reactivities and spectroscopic properties were studied and elucidated as astaxanthin diester and astaxanthin monoester. After saponification of carotenoid ester, GC analysis was performed. The carotenoid ester contained oleic acid, palmitic acid and palmitoleic acids as 50% of total amount, and had higher content unsaturated fatty acid including eicosapentanoic acid than saturated fatty acid.

• Journal of Practical Agriculture & Fisheries Research
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• v.14 no.1
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• pp.85-92
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• 2012

To elucidate the mycotoxin production of Penicillium, Aspergillus and Fusarium spp. isolated from round bale silage, TLC analysis of culture filtrates were conducted. Mycotoxin citrin and patulin were detected from culture filtrates of Penicillium paneum. Aflatoxin was detected from culture filtrates of Aspergillus flavus. Gliotoxin are known to produce by A. fumigatus was not detected. Mycotoxins produces by Fusarium spp., Fumonisin, zearalenone and deoxynivalenol was not detected in the culture filtrates of Fusarium proliferatum.