• Title/Summary/Keyword: 분자제조

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Properties of Lower Molecular Weight of $\lambda$-Carrageenan Manufactured by Ultrasound (초음파에 의해 제조된 저분자 $\lambda$-carrageenan의 특성)

  • KIM Sang-Moo;PARK Seong-Min;CHOI Hyeon-Mee;LEE Keun-Tae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.5
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    • pp.607-611
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    • 1999
  • Carrageenan are sulfated polymers containing galactose and anhydrogalctose units, and is used for its gelling, thickening, stabilizing, emulsifying, and suspending properties. However, carrageenan is limited to use beyond $0.03\%$ as food additives because of its high degree of gelling and viscosity with low solubility. The use of ultrasound significantly reduced the viscosity of $\lambda$-carrageenan solutions. The optimal parameters of ultrasound for reduction of carrageenan molecular weight were temperature, $10^{\circ}C$ ultrasound intensity, 114.7 $W/cm^2$ ; carrageenan concentration, $2\%$; treatment time, 10 min. The molecular weights of control, ultrasound peak 1, and peak 2 were approximately 250,000, 184,000, and 67,000 daltons, respectively. The lower molecular weight of $\lambda$-carrageenan showed the higher solubility, the lower alcohol precipitation ratio and the lower emulsifying capacity. Browning degree of both control and lower molecular $\lambda$-carrageenans was not significantly different.

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Production of Vinegar using Rubus coreanus and Its Antioxidant Activities (복분자를 이용한 식초의 제조 및 그의 항산화 효과)

  • Hong, Sung-Min;Kang, Min-Jeong;Lee, Ju-Hye;Jeong, Ji-Hye;Kwon, Seung-Hyek;Seo, Kwon-Il
    • Food Science and Preservation
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    • v.19 no.4
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    • pp.594-603
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    • 2012
  • This study developed a high-utility type of vinegar from Rubus coreanus by optimizing its fermentation conditions. In the alcohol fermentation process, the optimal conditions for the maximization of the alcohol contents were an initial sugar concentration of 15 $^{\circ}Brix$, a temperature of $30^{\circ}C$ and 4 days. The optimal conditions for the acetic acid fermentation were 9 days of fermentation at $30^{\circ}C$ and 200 rpm, with 6% alcohol and 2% initial acidity. The sucrose, fructose, and glucose contents were 952.90, 491.01, and 386.62 mg%, respectively. The free organic acids were acetic, malic, succinic, malonic, oxalic, and lactic acids. The total free amino acid content was 104.33 ${\mu}g/mL$, with alanine, glutamic acid, ${\gamma}$-amino-N-butyric acid, and o-phospho-ethanolamine as the major amino acids. The K, Na, and Mg contents were 1,686.10, 172.50, and 69.33 ppm, respectively. The total phenolic and anthocyanin contents were 25.19 and 80.71 mg/100 mL, respectively. The DPPH- and $ABTS^{.+}$ radical scavenging activities were approximately 65 and 94%, respectively. Moreover, the vinegar's ${\beta}$-carotene bleaching activity and reducing power showed that it had strong anti-oxidant properties. These results show that Rubus coreanus vinegar has anti-oxidant properties and may be used as functional food.

NEWS&TOPICS 해외

  • Min, Yeong-Gi
    • The Science & Technology
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    • no.1 s.404
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    • pp.12-13
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    • 2003
  • 미생물 조작 새로운 생명체 창조/ 병을 따지 않고도 포도주 맛 감지/ 나노튜브를 분자 단위로 용접/ 초전도체의 원자 구조 영상/ 다이아몬드 칩 제조 방법 개발/ 쥐 유전자 99%가 인간과 비슷/ 목성의 위성 아말데아에 많은 구멍/ 의대에서 살아있는 동물 실험 줄어든다

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Study on the Degradation of Pigskin Collagen Using Irradiation Technique (방사선조사를 이용한 돈피 콜라겐의 저분자화 연구)

  • Cho, Young-Jun;Seo, Jung-Eun;Kim, Yun-Ji;Lee, Nam-Hyouk;Hong, Sang-Pil;Kim, Young-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.5
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    • pp.588-593
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    • 2006
  • This study was intended to observe possibility of which radiation technique can be used for oligopeptide production from pigskin collagen to reduce environmental pollution in processing and simplify the processing steps. Raw pigskin was ground using chopper, and then defatted in acetone cooled at $-20^{\circ}C$ freezer. Defatted dried pigskin was irradiated at 20, 40, 60, 100, 150, 200, 250, and 300 kGy using Co-60 gamma rays irradiator. With irradiation doses, the amount of soluble proteins increased, and the viscosity and turbidity of soluble proteins decreased, which could be clue of that irradiation degrade high molecular proteins directly. pH of soluble proteins from defatted pigskin increased in the sample above 150 kGy, and low molecular weight components (below 24 kDa) in SDS-PAGE increased. From gel permeation chromatography of the hydrolysates of pigskin irradiated at 300 kGy showed the major peak of 9,000, 8,200, 860, and 170 Da.

A Study of Drug Content and Cell Cytotoxicity of Paclitaxel-eluting Stents Coated with Various Biopolymer (다양한 생체고분자로 코팅된 Paclitaxel Eluting Stent의 약물함량과 세포독성 연구)

  • Kim, Dong-Gon;Shin, Il-Gyun;Kim, Gi-Han;Kim, Seong-Hyeon;Lee, Ju-Ho;Ki, Byoyng-Yun;Nah, Jae-Woon;Suh, Tae-Suk;Kim, Sang-Ho
    • Progress in Medical Physics
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    • v.20 no.3
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    • pp.125-131
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    • 2009
  • In this study, the paclitaxel eluting stent (PES) was prepared by coating a biliary stent with paclitaxel using various biopolymer such as poly (vinyl acetate) (PVAc), poly (lactic-co-glycolic acid) (PLGA), Silicone rubber for restenosis prevention in gastrointestinal disease by a dip-coating method. Drug contents of PES were increased as surface area of stent, concentration and molecular weight of coating polymer increase. In $^1H-NMR$ specta, we know that drug did not change by confirming specific peaks of paclitaxel in PES. As shown in SEM image, PES prepared using various biopolymer is coated clearly and regularly except Silicone rubber coating polymer. In in vitro cell cytotoxicity test, bare stent showed low cytotoxic effect against CT-26 colon carcinoma cell line on 3 day. However, PES coated with PLGA 502H showed the highest cytotoxicity because PLGA 502H is biodegradable polymer and has less molecular weight than other coating polymer. These results suggest that PES coated various biopolymer can be prevented restenosis in gastrointestinal disease.

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Effect of Molecular Weight of PLGA on Release Behavior of Doxorubicin for Double-Layered PLGA Microspheres (PLGA 분자량에 따른 이중층 독소루비신 미립구의 방출거동)

  • Park, Jung-Soo;Yang, Jae-Chan;Yuk, Soon-Hong;Shin, Hyung-Shik;Rhee, John-M.;Kim, Moon-Suk;Lee, Hai-Bang;Khang, Gil-Son
    • Polymer(Korea)
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    • v.31 no.3
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    • pp.189-193
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    • 2007
  • We developed the doxorubicin-loaded PLGA double-layered microspheres using relatively simple oil-in-water (O/W) solvent evaporation method for sustained release of doxorubicin and investigated the release behavior according to PLGA molecular weight and initial drug loading. The double-layered microsphere was characterized on the surface, the cross-section morphology, the behavior of doxorubicin release for 5 weeks by SEM and fluorescence spectrophotometer. Double-layered microspheres showed smooth surfaces and clear difference between core and outer-shell. As the PLGA molecular weight increased, the release rate of doxorubicin-loaded, double-layered microspheres decreased. These results showed that the release behaviors can be controlled by the variation of molecular weight of PLGA.