• Title/Summary/Keyword: hydrophilic acid

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Effect of Coloration on the Hydrophilicity and Swelling Properties of Poly-HEMA Hydrogels

  • Jang, Jin-Ho;Park, Hwa-Sung;Jeong, Yong-Kyun
    • Textile Coloration and Finishing
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    • v.19 no.2
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    • pp.7-13
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    • 2007
  • Photopolymerization of 2-hydroxyethyl methacrylate(HEMA), in the presence of ethyleneglycol dimethacrylate(EGDMA) and 1-Hydroxycyclohexyl phenyl ketone as crosslinker and photoinitiator, respectively, produced crosslinked poly-HEMA hydrogels. The hydrogels were colored by the exhaustion of vinylsul-phone-type reactive dyes. Good colorfastness to laundering was achieved when colored with C.I. Reactive Black 5. We investigated that the effect of coloration on the hydrophilicity and swelling properties of the films. More hydrophilic gel-surfaces were generated with in increase in coloration and crosslinking. Higher surface energy was observed with higher crosslinking level. The more rapid and higher water swellability of poly-HEMA gels after coloration may be resulted from a more opened gel structure by the easier hydration of the hydrophilic sulphonic acid groups of the reacted dyes in water.

Amphiphilic Cyclotriphosphazenes Grafted with Branched Oligopeptides

  • Jadhav, Vithal B.;Toti, Udaya S.;Cui, Jin Xin;Jun, Yong-Joo;Sohn, Youn-Soo
    • Bulletin of the Korean Chemical Society
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    • v.31 no.12
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    • pp.3735-3739
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    • 2010
  • Branched oligopeptides prepared by coupling a very hydrophobic aspartic diamino acid ethyl ester such as Asp $(LeuEt)_2$, $Asp(IleEt)_2$ and $Asp(PheEt)_2$ to glycine or glycylphenylalanine were grafted to the cyclotriphosphazene backbone bearing an equimolar hydrophilic poly(ethylene glycol) (PEG). The properties of the resultant amphiphiles were examined in comparison with those of the linear oligopeptide analogues previously reported. All cyclic phosphazene trimers grafted with the branched tetra- and pentapeptides displayed a normal trend of thermosensitivity depending on their hydrophilic to hydrophobic balance, but the stability and particle size of their micelles were found to be greatly dependent on the fine structure of the branched oligopeptides grafted. The trimers bearing branched tetrapeptides with a low hydrophobicity were found to form unstable micelles initially, which reassemble into thermodynamically more stable polymersomes.

Antioxidative Materials in Domestic Meju and Doenjang 1.Lipid Oxidation and Browning during Fermentation of Meju and Doenjang (재래식 메주 및 된장중의 항산화성 물질에 관한 연구 1. 메주 발효 및 된장 숙성중의 지질산화와 갈변)

  • 이종호;김미혜;임상선
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.2
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    • pp.148-155
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    • 1991
  • Lipid oxidation and browning during fermentation of domestic Meju and Doenjang were examined in order to elucidate the antioxidative effects of browning products and phenol compounds from Meju and Doenjang. Peroxide values of lipids from Meju were detectable and slightly increased until 3 weeks of fermentation, but started to be decreased after 3 weeks of fermentation and notdetectable after 6 weeks. Peroxides were not detected in Doenjang during the whole fermentation, but started to be decreased after 3 weeks of period of 22 weeks fermentation. Carbonyl value were increased during the whole period of Meju fermentation, but started to be decreased at the early stage of Doenjang fermentation. Hydrophilic fraction of browning products from Meju was much higher than lipophilic fraction and the former fraction was dramatically increased at the early stage of the fermentation. But the both fractions maintained high values during Doenjang fermentation. Hydrophilic browning products and phenol and phenol compound in Meju showed strong antioxidative against linoleic acid.

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Preparation and Characterization of Polyamide Thin Film Composite Reverse Osmosis Membranes Using Hydrophilic Treated Microporous Supports (친수성 처리된 다공성 지지체를 이용한 폴리아마이드 박막 역삼투 복합막 제조 및 특성 분석)

  • Son, Seung Hee;Jegal, Jonggeon
    • Membrane Journal
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    • v.24 no.4
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    • pp.317-324
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    • 2014
  • It is very well known that the conventional polyamide (PA) thin film composite (TFC) reverse osmosis (RO) membranes have excellent permselective properties, but their chlorine tolerance is not good enough. In this study, to improve such chlorine tolerance, microporous membranes containing hydrophilic functional groups such as -COOH were used as a support to prepare PA TFC RO membranes, employing the conventional interfacial polymerization method. Meta-phenylene diamine (MPD) and 2,6-diamine toluene (2,6-DAT) were used as diamine monomers and tri-mesoyl chloride (TMC) as an acid monomer. The membranes prepared were characterized using various instrumental analytical methods and permeation test set-up. The flux obtained from the membranes prepared so was more than $1.0m^3/m^2day$ at 800 psi of operating pressure, while the salt rejection was over 99.0%. The chlorine tolerance of them was also found to be better than that of the membrane prepared by using conventional polysulfone support without hydrophilic functional groups.

Anti-diabetic Effects of Banaba Leaf Extracts (Lagerstroemia speciosa Pers.) through Solvents (추출용매 변화에 따른 바나바(Lagerstroemia speciosa Pers.) 잎 추출물의 항당뇨 효과)

  • Kim, Kyun-Ha;Roh, Sang-Geun;Li, Chun-Ri;Jin, Chun-Feng;Kim, Andre;Choi, Won-Chul
    • Journal of Life Science
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    • v.18 no.9
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    • pp.1305-1311
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    • 2008
  • This study investigated that the antidiabetic effects of banaba extracts with variety solvents selectivity in vitro and in vivo. Banaba extracts were prepared with water, 70% ethanol, 90% ethanol, 100% ethanol and water-ethanol that of extract twice times sequentially water and ethanol. Cell toxicity and insulin secretion of banaba extracts was tested by MTT (3-[4,5-dimetylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay on hamster insulinoma cell line, HIT-T15. Also we tested that insulin, body weight, blood glucose, total cholesterol, HDL-cholesterol, triglyceride and free fatty acid in streptozotocin diabetic rats. Water-ethanol extract has remarkable antidiabetic effect compare with the other banaba extracts. For water-ethanol extract has both of hydrophilic and hydrophobic antidiabetic materials from banaba. Expecially, corosolic acid, as known as unique polyphenol, has antidiabetic effect studied by many researchers till nowadays. But corosolic acid does not solve in water. Otherwise, we suggest that banaba extract of hydrophilic and hydrophobic materials (polyphenol and antioxidants) mixture more increased antidiabetic effects.

Hydrophilic Modification of Polypropylene Microfiltration Membrane by Radiation-Induced Graft Polymerization and Water Permeability (방사선 조사 그라프트중합에 의한 폴리프로필렌 정밀여과막의 친수화 및 물 투과특성)

  • Park, Jae-Hyung;Lee, Kune-Woo;Hwang, Taek-Sung;Lee, Jae-Won;Oh, Won-Jin
    • Applied Chemistry for Engineering
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    • v.10 no.6
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    • pp.954-959
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    • 1999
  • Radiation-induced grafting of 2-hydroxyethyl methacrylate(HEMA), acrylic acid(AAc) and methacrylic acid(MAAc) onto polypropylene microfiltration membrane has been studied. The effect of grafting conditions such as solvent composition(MeOH and $H_2O$) and monomer concentration on the grafting yield in investigated. The highest degree of grafting is obtained at a solvent composition of 25% $H_2O$:75% MeOH for HEMA, pure water for AAc and 50% $H_2O$:50% MeOH for MAAc. Modification of the PP membranes with hydrophilic monomers is shown to cause an increase in the water permeation flux of the membranes. It is found that HEMA is the best monomer to increase the water permeation flux and the highest water permeation flux is obtained at 99% degree of grafting. The water permeation flux of AAc-grafted PP membrane and MAAc-grafted PP membrane is very sensitive to environmental pH and $Cu^{2+}$ ion, but the water permeation flux of HEMA-grafted PP membrane scarcely depends on pH and $Cu^{2+}$ ion.

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An Experimental Study on the Effect of Angelica gigas Ethanol Extract on Hyaluronic Acid Synthesis (Angelica gigas 에탄올 추출물의 Hyaluronic acid 합성 효과에 대한 실험적 연구)

  • Park, Hye-Su;Ha, Hun-Yong;Kim, Hee-Taek
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.31 no.1
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    • pp.32-41
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    • 2018
  • Objectives : Hyaluronic acid(HA) is a mucopolysaccharide, occuring naturally in living organisms. It is one of the most hydrophilic molecules, so it has been known as being related to skin hydration and skin aging. The purpose of this study is to examine the effects of Angelica gigas(A. gigas) ethanol extract on hyaluronic acid synthesis. Methods : To determine cytotoxicity and hyaluronic acid synthase 2 gene expression, hyaluronic acid production in HaCaT cells, MTT assay and RT-PCR ELISA was used. Results : There were no cytotoxicity in $50{\mu}g/ml$ concentration A. gigas extract in MTT assay. Hyaluronic acid synthase 2(HAS2) gene expression was increased by all treated concentration A. gigas extract. Hyaluronic acid production was higher than control group in $50{\mu}g/ml$ & $100{\mu}g/ml$ concentration A. gigas extract. Conclusions : Hyaluronic acid production was increased by A. gigas extracts. Therefore, We suggest that A. gigas can make a contribution to the moisturizing effect on human skin.

Synthesis of 6- Hydroxy-7 -methoxychroman-2-carboxylic Acid Dialkylaminoalkylamides (6-하이드록시-7-메톡시크로만-2-카복실산 디알킬아미노알킬아마이드 합성)

  • Kwak, Jae-Hwan;Lee, Keum-Ho;Jung, Jae-Kyeong;Cho, Jung-Sook;Lee, Hee-Soon
    • YAKHAK HOEJI
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    • v.50 no.5
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    • pp.322-325
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    • 2006
  • In the course of developing novel antioxidants, we synthesized four of 6-hydroxy-7-methoxy-4-oxochroman-2carboxylic acid dialkylamides (3a-d) $(13{\sim}18%)$ and four of 6-hydroxy-7-methoxychroman-2-carboxylic acid dialkylamides (4a-d) $(52{\sim}89%)$, incorporating the basic amine functionality. None of these compounds exhibited significant antioxidant activity possibly due to the hydrophilic character of the basic amine side chains.

Polyethyleneimine Derivative for Nucleic Acid Model

  • Lee, Chan-Woo;Chae, Hee-Jeong;Kwon, Young-Jin
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.3
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    • pp.205-211
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    • 2005
  • Water-soluble polyethyleneimine (PE) derivatives containing nucleic acid bases and hydrophilic amino acids such as homoserine (Hse) and serine were prepared by the activated ester method as nucleic acid models. From spectroscopic measurements, the polymers were found to interact with DNA accompanied by an induction of conformational change. Hypochromicity in UV spectra indicated that a stable polymer complex was formed between poly (A) with PEI­Hse-Ura by complementary hydrogen bonding with equimolar nucleic base units (adenine:uracil=1:1). The induced conformation of DNA by the interaction with the polymer containing uracil and homoserine (PEI-Hse-Ura) was concluded to be a super triple helical structure. The formation of the polymer complex, DNA: PEI-Hse-Ura, was found to be affected by the presence of metal ions such as $Ca^{2+}\;and\;Cu^{2+}$.

Characteristics of L-Ascorbic Acid Encapsulated BGsome and its Stabilization Effect (L-ascorbic acid가 포집된 BGsome의 특성 및 안정화 효과)

  • Hwang, Sue-Yun;Jin, Byung-Suk
    • Journal of the Korean Applied Science and Technology
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    • v.28 no.3
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    • pp.313-320
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    • 2011
  • Encapsulation of L-ascorbic acid(AA) into BGsome was attempted to improve its stability. BGsome is a bio-compatible vesicular system prepared by dispersion of hydrated liquid crystalline phase formed through hydration of 1,3-butylene glycol(BG)-dissolved lecithin with an aqueous solution containing hydrophilic component. The characteristics of AA encapsulated BGsome, such as droplet size, surface charge, and solution appearance, was investigated. The concentration of AA solution had considerable effect on droplet size and surface charge of BGsome. Several tens nanometer droplet made by sonication treatment did not showed any change of size with storage time. Stability of AA was improved by encapsulation into BGsome, which was verified through DPPH test and HPLC assay.