• 제목/요약/키워드: ACID property

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Synthesis and Chromatographic Characteristics of Multidentate Ligand-Boned Silica Stationary Phases

  • Li, Rong;Wang, Yan;Chen, Guo-Liang;Shi, Mei;Wang, Xiao-Gang;Zheng, Jian-Bin
    • Bulletin of the Korean Chemical Society
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    • 제31권8호
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    • pp.2201-2206
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    • 2010
  • To improve the separation property and stability of metal chelate Cu(II) column, three new kinds of multidentate aminocarboxy silica columns with cation-exchange properties were synthesized using glutamic acid (Glu), glutamic acidbromoacetic acid (Glu-BAA), glutamic acid-bromosuccinic acid (Glu-BSUA) as ligands and silica gel as matrix. The standard proteins were separated with prepared chromatographic columns. The stationary phases exhibited the metal chelate property after fixing copper ion (II) on the synthesized multidentate ligand silica columns. The binding capacity of immobilized metal ion was related with the dentate number of multidentate ligands. Chromatographic behavior of proteins and the leakage of immobilized metal ion on multidentate chelate Cu(II) columns were affected by the dentate number of multidentate ligands and competitive elution system directly. The results showed that quinquedentate Glu-BSUA-Cu(II) column exhibited better chromatographic property and stability as compared with tridentate Glu-Cu(II) column, tetradentate Glu-BAA-Cu(II) column and commonly used IDA-Cu(II) column.

녹차와 쑥차를 첨가한 요구르트이 제조와 품질 특성 (Preparation of Yogurt Added with Green Tea and Mugwort Tea and Quality Characteristics)

  • 방병호;박홍현
    • 한국식품영양과학회지
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    • 제29권5호
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    • pp.854-859
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    • 2000
  • A functional yogurt was prepared from whole milk (12%) and skim milk (2%) added with green tea and mugwort tea at 3$0^{\circ}C$ for 24 hors. The yogurt product were evaluated for acid production (pH, titratable acidity), number of viable cell, viscosity, sensory property and quality-keeping property. Addition of green tea and mugwort tea remarkably accelerated acid production of yogurt. After 24 hrs incubation, titratabel acidity of green tea and mugwort tea yogurt was 1.46% and 1.62%, respectively and was higher than that (1.30%) of yogurt made with only milk. The propagation of lactic acid bacteria was not stimulated by green tea and mugwort tea and then the number of viable cell in normal (milk) yogurt green tea yogurt and mugwort tea yogurt groups, after 24 hrs incubation, was about 7.2$\times$$10^{8}$, 7.1$\times$$10^{8}$ and 7.0$\times$$10^{8}$/mL, respectively, Viscosity of green tea yogurt was slightly lower than that of milk yogurt (1,840 cps) and viscosity of mugwort tea yogurt was slightly higher than that of mild yogurt. The overall sensory score of green tea yogurt was the best of tested yogurt. When yogurt with green tea and mugwort tea was kept at 5$^{\circ}C$ for 15 days, its quality-keeping property was relatively good.

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Physicochemical Properties of Job's Tears (Coix lachryma-jobi L.) Starch Modified with Different Levels of Acid Hydrolysis

  • Kim, Hye-Won;Lee, Kwang-Yeon;Bae, In-Young;Jun, Soo-Jin;Lee, Ji-Yeon;Lee, Hyeon-Gyu
    • Food Science and Biotechnology
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    • 제18권5호
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    • pp.1145-1149
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    • 2009
  • Physicochemical properties of native and acid-modified Job's tears (Coix lachryma-jobi L.) starches were investigated. Starch extracted from Job's tears was treated with 2.2 N hydrochloric acid for different length of time (3, 6, 12, and 18 hr). The hydrolysis pattern of starches with the acid proceeded rapidly up to 12 hr and then the approached constant values. The swelling power of acid-modified starches measured at all temperatures was lower than that of its native counterparts and the water solubility index increased as temperature and hydrolysis time increased. Rapid visco analyzer viscograms of acid-modified starches demonstrated a very low viscosity as compared with that of native starch. However, Xray diffraction did not show any significant alteration in the crystallinity after acid-modification.

Evaluation of Molecular Weight Distribution, Pasting and Functional Properties, and Enzyme Resistant Starch Content of Acid-modified Corn Starches

  • Koksel, Hamit;Ozturk, Serpil;Kahraman, Kevser;Basman, Arzu;Ozbas, Ozen Ozboy;Ryu, Gi-Hyung
    • Food Science and Biotechnology
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    • 제17권4호
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    • pp.755-760
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    • 2008
  • The aim of this study was to produce resistant starch preparations from acid-modified com starches prepared at various hydrolysis levels (0.5-4.0 hr). Effect of autoclaving cycles on resistant starch (RS) formation was investigated. Molecular weight distribution, pasting and functional properties of acid-modified com starches were determined. For RS formation native and acid-modified starch samples were gelatinized and autoclaved (1 or 2 cycles). While native and acid-modified starches did not contain any RS, the levels increased to 9.0-13.5% as a result of storage at $95^{\circ}C$ after first autoclaving cycle. Second autoclaving cycle together with storage at $95^{\circ}C$ brought final RS contents of the samples incubated at 4 and $95^{\circ}C$ after the first cycle to comparable level. As acid modification level increased, the amount of high molecular weight fractions decreased, resulting in significant decreases in viscosities (p<0.05). The samples produced in this study had low emulsion stability and capacity values.

Synthesis of Some Phosphated Fatty acyl Derivatives of Mannitol and Their Evaluation

  • Jain, Sanjay;Tripathi, Meena;R.K.Uppadhyay;D.V.Kohli
    • Archives of Pharmacal Research
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    • 제12권4호
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    • pp.233-235
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    • 1989
  • Sodium salts of phosphated capric and myristic acyl derivatives of mannitol were prepared and evaluated for surface activity, foam characteristics and emulsifying properties. Triacyl mannitols of cappric and myristic acid have better emulsifying property than the corresponding di and monocompounds.

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상어간유에서 스쿠알렌과 알콕시글리세롤의 물성 및 추출 (Physical Property and Extraction of Squalene and Alkoxyglycerol from Shark Liver Oil)

  • 이수일;허효정;노경호
    • Korean Chemical Engineering Research
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    • 제49권5호
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    • pp.617-622
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    • 2011
  • 심해상어 간유에서 추출한 천연유지는 스쿠알렌(Squalene)과 알콕시글리세롤(Alkoxyglycerol)을 함유하고 있다. 본 연구에서는 심해상어 간유에서 피부 보호능력이 있는 스쿠알렌과 면역작용이 우수한 알콕시글리세롤을 추출하고 GC-MS 분석을 통하여 정제과정을 거친 스쿠알렌과 알콕시글리세롤의 함량 변화를 비교하고 스쿠알란과 함께 물성을 평가하였다. 스쿠알렌의 함량은 정제과정을 거친 뒤에 35% 더 증가하였으며 알콕시글리세롤의 함량은 21.9% 더 증가한 것을 볼 수 있었다. 상어간유를 알콕시글리세롤 정제과정을 통해 지방산은 61%에서 4%로 57%의 지방산이 제거된 것을 확인할 수 있었고, 지방산 중 Palmitic acid와 Oleic acid의 함량이 크게 감소된 것을 확인할 수 있었다. 상어간유에 과산화물가와 산가는 스쿠알렌 정제과정을 거친 후 크게 낮아진 것을 확인하였고 불포화 지방산이 이중결합이 많은 스쿠알렌이 스쿠알란(Squalane)보다 요도드가가 월등히 큰 것을 확인하였다.

$\beta$-시클로덱스트린화 셀룰로오스 섬유의 제조 및 소취성 (Preparation of $\beta$-Cyclodextrinized Cellulosic Fiber and Deodouring Property)

  • 최창남;황태연;고봉국;김용;홍성학;김상률
    • 폴리머
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    • 제25권5호
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    • pp.635-641
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    • 2001
  • 포접 기능을 가져 악취의 분리제거에 사용될 수 있을 것으로 보이는 $\beta$-시클로덱스트린 및 $\beta$-시클로덱스트린에 벤조산을 포접시킨 물질($\beta$-시클로덱스트린/벤조산 포접체)에 시아누르산 염화물을 반응시켜 클로로트리아진 유도체를 제조하고, 이를 면섬유와 반응시켜 새로운 소취 기능성 섬유를 제조하였다. 포접체의 형성은 적외선 분광분석 및 가시-자외선 분광분석기를 사용하여 확인하였으며, 반응기의 도입은 EDX로 확인하였다. 소취성능은 제조한 소취기능성 섬유를 컬럼에 채우고, 암모니아 기체를 흘려 보냈을 때 빠져나온 암모니아를 물에 용해시킨 용액의 농도를 0.1N 염산으로 적정하여 평가하였다. 섬유에 부착된 $\beta$-시클로덱스트린 단위가 증가할수록 소취성이 증가하였으며, $\beta$-시클로덱스트린에 벤조산을 포접한 경우에 소취성이 보다 증가하였다. 이는 포접체에 존재하는 벤조산과 암모니아의 결합때문이라고 생각되었다.

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새로운 엽산 대사 길항제의 합성 및 약리활성 (Synthesis and Pharmacological Activities of New Folic Acid Antagonists)

  • 신관석;성선영;남재우;최상운;이정옥
    • 약학회지
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    • 제36권4호
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    • pp.326-333
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    • 1992
  • A new series of methotrexate analogues was prepared in which the ${\beta}-position$ of the glutamic acid moiety is substituted by the aryl groups. The glutamic acid moiety was modified in order to enhance the lipophilic property. Reaction of N-acetylglicine ester[1] with ethyl 3-arylacrylate derivatives[2] produced trans-3-aryl-2-carboxy-5-pyrrolidone derivatives[3], which were hydrolyzed to give ${\beta}-aryl-glutamic$ acid derivatives[4]. The compounds[4] were treated with the p-aminobenzoic acid moiety and then with the pteridine ring moiety to give ${\beta}-arylmethotrexate$ derivatives[6,7]. These compounds were tested for antibacterial activity against Streptococcus faecium and for antitumor activity against murine leukemias and against human tumor cell lines in vitro. Several compounds showed significant antibacterial activity.

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오일 팜 수간 유래 CNF (cellulose nanofibrils)의 화장품 보습제 적용을 위한 보습력 평가 (Evaluation of water holding property for applying a cosmetic moisturizer from oil palm trunk CNF)

  • 송우용;신수정
    • 펄프종이기술
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    • 제48권2호
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    • pp.91-98
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    • 2016
  • Cellulose nanofibrils (CNF) was made from oil palm trunk (OPT) with soda-anthraquinone pulping, chlorine dioxide bleaching, carboxymethylation, followed by mechanical grinding. Size of this CNF was 16-40 nm of width confirmed by TEM. To evaluate CNF from OPT as cosmetics raw materials for moisturizing component, water holding properties was compared with hyaluronic acid and collagen. CNF from OPT had better water holding property than collagen or hyaluronic acid whether phenoxyethanol was added as antiseptic or without additive.

Hygroscopic Property, Leaching Resistance and Metal Corrosive Efficacy of Wood Treated with Fire Retardants

  • Son, Dong Won;Kang, Mee Ran;Hwang, Won Joung;Lee, Hyun Mi;Park, Sang Bum
    • Journal of the Korean Wood Science and Technology
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    • 제42권2호
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    • pp.157-162
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    • 2014
  • This study was conducted to examine the functionality of the fire retardant treated wood. The hygroscopic property, leaching resistance, metal corrosive efficacy and gas toxicity of retardant treated wood were analyzed. Sodium silicate was penetrated to the wood for making fire retardant treated wood. The subsequent treatment agents such as boric acid, ammonium borate, di-ammonium phosphate were treated after sodium silicate treatment due to fixation. As results for the test, the leaching resist was improved by subsequent treatment. The fire retardant combination such as sodium silicate, boric acid and di-ammonium phosphate showed high hygroscopic property, metal corrosive efficacy. The gas toxicity was also satisfied KS standard.