• Title/Summary/Keyword: Fraction

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Heat Inactivation of Proteolytic Enzymes in Papaya Latex (Papaya Latex에 있는 단백질분해효소(蛋白質分解酪素)들의 열불활성(熱不活性)에 관하여)

  • Noh, Bong-Soo;Park, Kwan-Hwa
    • Korean Journal of Food Science and Technology
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    • v.12 no.3
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    • pp.209-215
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    • 1980
  • Proteases from papaya latex were partially purified by ammonium sulfate precipitation and separated into two fractions (Fraction I and II ) by carboxymethyl cellelose column chromatography. Each fraction, mixture of the two fractions, and crude extract of the papaya latex at pH 7.0 were inactivated at the range of $60{\sim}90^{\circ}C$ and thermal properties of the enzymes were investigated. In the thermal inactivation of fraction I, the enthalpy of activation was 89.5 kJ/mol; the entropy of activation, -44.0 J/mol K; the free energy of activation, 104.6 kJ/mol; z-value, $25^{\circ}C$. For fraction II, the enthalpy of activation was 96.5 kJ,/mol; the entropy of activation, -22.0 J/mol K; the free energy of activation, 104.0 kJ/mol; z-value, $23^{\circ}C$. For the mixture of fraction I and II, the enthalpy of activation was 90.9 kJ/mol; the entropy of activation, -38.8 J/mol·K; the free energy of activation, 104.2 kJ/mol; z-value, $24.6^{\circ}C$. For crude extract, the enthalpy of activation was 113.8 kJ/mol; the entropy of activation, 22.0 J/mol·K; the free energy of activation, 106.2 kJ/mol; z-value, $23.2^{\circ}C$. It was indicated that the fraction I was more heat-stable than the fraction II and this suggested that the thermal stability of the proteases in papaya latex is probably due to the fraction I.

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Functional Components of Barley Bran with Different Particle Sizes and Cultivars (품종 및 입도별 보리 맥강의 기능성분 함량)

  • Baek, So Yune;Lee, Yoon Jeong;Jang, Gwi Young;Kim, Min Young;Oh, Nam Seok;Lee, Mi Ja;Kim, Hyun Young;Lee, Jun Soo;Jeong, Heon Sang
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.10
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    • pp.1171-1177
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    • 2017
  • This study evaluated the functional components of barley bran with different particle sizes and cultivars (Dahan, Hinchalssalbori, Heukgwang, Huknuri, and Boseokchal). Barley bran divided into fractions I (<60 mesh), II (60~100 mesh), and III (>100 mesh) was collected as pearling by-products produced by an industrial process consisting of consecutive barley pearlers. Total ${\beta}-glucan$ contents of all cultivars were especially highest in fraction II. Total arabinoxylan was the highest in barley bran from Boseokchal in fraction II. Total polyphenol contents were the highest in bran from Boseokchal and Hinchalssal in fraction II, and contents ranged of 5.61~7.00 and 4.24~6.58, respectively. Total flavonoid contents of all cultivars were especially highest in fraction II. 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities ranged from 2.78~7.53 mg L-ascorbic acid (AA) eq/g and 2.24~4.83 mg AA eq/g, respectively. ABTS and DPPH radical scavenging activities were the highest in barley bran from Dahan in fraction II. In this study, fraction II showed enriched functional components and has the best particle size range for enriched antioxidant activities. These results provide useful data for selection of appropriate cultivars and particle size of bran to achieve high quality barley processing.

A Study on Texture of Jeung-pyun According the Kinds of Rice (쌀 품종에 따른 증편의 조직특성에 관한 연구)

  • 김효진;이숙미;조정순
    • Korean journal of food and cookery science
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    • v.13 no.1
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    • pp.7-15
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    • 1997
  • The composition and polymeric structure of starch are the most important factors to determine the functional properties of rice. In an effort to relate the structural characteristics and its functional properties of starch in rice, molecular structural properties of starch from 6 rice cultivars were analysed. To relate the structure and function of starch the texture of Jeung-pyun made of rice were analyzed during retrogradation. The polymeric structure of rice starch was analyzed by debranching with isoamylase after gelatinization and fractionated with Sephadex G-75 gel filteration. The size fractionated debranched starch was categorized into four groups such as Fraction I, II, III and Intermediate Fraction depending in their max, The fractions with the max higher than 620 nm were designated as Fraction I, while those in the range of 600-620 nm and 540-600 nm as the Intermediate Fraction and Fraction II, respectively. The Fractions with the max lower than 540 were described as Fraction III. The average degree of polymerization (DP) of the Fraction I was estimated to be higher than 200, and those of other fractions, i.e. the Intermediate Fraction I, Fraction II and III were 150,45 and 25, respectively. The levels of Fraction I were varied from II to 35% of total sugar. The Fraction I showed the linear relationship with the amylse contents, and the Intermediate Fraction, which might contain the mixture of short chain of amylose and debranched long chain of amylopectin, were measured to be in the range of 2.7∼8.4%. The levels of fraction II and III, both to be considered as the branches of amylopectin, were ranged 14.5∼23.6% and 39.7∼73.0%, respectively. The ratio of Fraction III to Fraction II describing the degree of branch or compactness of amylopectin was estimated to be around 4.0 for waxy varieties and around 2.0 for high amylose cultivars. With these results, it can be suggested that the degree of branch of the amylopectin may effect on amylose contents of starch or rice versa, To invertigate processing aptitude of different rice cultivars for the preparation of Jeung-pyun, its texture was analyzed by Instron, hardness, cohesiveness, elasticity, gumminess and chewiness of Jeung-pyun made of rice showed the significant relationship with the amylose content. Hardness was increased during retrogradation of product, but the relationship between hardness and amylose content due to not only difference in amylose content but also difference in structural characteristics of starch. In analysis of relationship between structure of rice starch and mechanical properties of Jeung-pyun during retrogradation elasticity did not show any relationship before retrogradation bur during retrogradation showed significant correlation. With these result, it can be suggested that the degree of branch of the amylopectin may effect on elasticity during retrogradation. However hardness, cohesiveness, gumminess and chewiness which were significant different before retrogradation, showed some correlation with structure of rice starch during retrigradation.

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The Effect of Ginseng Butanol Fraction on the Acetaldehyde Metabolism in Mice (마우스의 아세트알데히드 대사에 미치는 인삼 부탄올 분획의 영향)

  • Huh, Keun;Park, Chong-Min;Lee, Sang-Il;Choi, Chong-Won
    • YAKHAK HOEJI
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    • v.29 no.1
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    • pp.18-26
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    • 1985
  • The present study was undertaken to investigate the possible effect of ginseng butanol fraction on the hepatic acetaldehyde metabolism. Experimental animals were used for the subject of the study. When, in case of mitochondrial aldehyde dehydrogenase (Ald DH), ginseng butanol fraction was added, enzyme activity was increased in a small dose, while, in a large dose, it showed inhibitory effect. In terms of kinetic aspect, ginseng butanol fraction has the effect to decrease the Km values of Ald DH. In vivo studies, the activity of Aid DH increased by induction of acute intoxication of ethanol was further increased through pretreatment with ginseng butanol fraction. When ginseng butanol fraction was given to mice fed with 5% ethanol instead of water for 60 days, the activity of Ald DH in mitochondrial fraction decreased to about 35% in chronic alcoholism, but after pretreatment of ginseng butanol fraction the activity was restored to the control level. By the pretreatment with disulfiram, the Ald DH activity was inhibited in normal and alcohol-treated groups, but after the treatment with ginseng butanol fraction the activity was restored to the control level. The results suggest that ginseng butanol fraction enhance the Ald DH activity inhibited by the treatment of disulfiram with no relation to NAD. It was observed that ginseng butanol fraction markedly decrease the acetaldehyde levels in plasma and liver. All these observations suggested that reduction of acetaldehyde in blood and liver should be dependent upon increased activity of mitochonclrial Ald DH. It is concluded that the recovery from alcohol intoxication should be prompted by treatment with ginseng.

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The Effects of Microstructure in Austenitic 316L Stainless Steels on the Strength and Damping Capacity (오스테나이트계 316L 스테인리스강의 강도 및 감쇠능에 미치는 미세조직의 영향)

  • SON DONG-WOOK;LEE JONG-MOON;KIM HYO-JONG;NAM KI-WOO;PARK KYU-SEOP;KANG CHANG-YONG
    • Journal of Ocean Engineering and Technology
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    • v.20 no.1 s.68
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    • pp.1-6
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    • 2006
  • The effects of microstructure on the damping capacity and tensile properties of 316L stainless steel were investigated. Increasing the degree of cold working, the volume fraction of $\varepsilon-martensite$ decreased after rising to maximum value at specific level of cold working, the volume fraction of d-martensite slowly increased and then dramatically increased from the point of decreasing $\varepsilon-martensite$ volume fraction. Increasing the degree of cold working, the behnvior of damping capacity is similar to that of the $\varepsilon-martensite$. After the damping capacity showing the maximum value at about $20\%$ of cold rolling, damping capacity was decreased with the volume fraction of $\varepsilon-martensite$. Tensile strength was proportional to the volume fraction of d-martensite, and elongation steeply decreased in the range low volume fraction of a'-martensite, then slowly decreased in range the above $10\%$ volume fraction of d-martensite. The damping capacity and elongation is strongly controlled by the volume fraction of $\varepsilon$ martensite with liner relationship. However, the effect of the volume fraction of d-martensite and austenite phase on the damping capacity was not observed. Tensile strength was governed by the volume fraction of d-martensite.

Separation of soil Organic Debris using Sucrose-ZnCl2 Density Gradient Centrifugation

  • Jung, Seok-Ho;Chung, Doug-Young;Han, Gwang-Hyun
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.1
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    • pp.30-36
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    • 2012
  • The active fraction of soil organic matter, which includes organic debris and light organic fraction, plays a major role in nutrient cycling. In addition, particulate organic matter is a valuable index of labile soil organic matter and can reflect differences in various soil behaviors. Since soil organic matter bound to soil mineral particles has its density lower than soil minerals, we partitioned soil organic matter into debris ($<1.5g\;cm^{-3}$), light fraction ($1.5-2.0g\;cm^{-3}$), and heavy fraction ($>2.0g\;cm^{-3}$), based on high density $ZnCl_{2-}$ sucrose solutions. Generally, partitioned organic bands were clearly separated, demonstrating that the $ZnCl_{2-}$ sucrose solutions are useful for such a density gradient centrifugation. The available gradient ranges from 1.2 to $2.0g\;cm^{-3}$. Although there was not a statistically meaningful difference in organic debris and organomineral fractions among the examined soils, there was a general trend that a higher content of organic debris resulted in a higher proportion of light organomineral fraction. In addition, high clay content was associated with increased fraction of light organomineals. Partitioning of soil organic carbon revealed that carbon content is reduced in the heavy fraction than in the light fraction, reflecting that the light fraction contains more fresh and abundant carbon than the passive resistant fraction. It was also found that carbon contents in the overall organic matter, debris, light fraction, and heavy fractions may differ considerably in response to different farming practices.

Studies on the Naringinase Produced by Aspergillus nidulans (Part I) Purification and Characteristics of Naringinase (Aspergillus nidulans 가 생산하는 Naringinase 관한 연구 (제2보) Naringinase의 정제 및 물리화학적 성질)

  • 변유량;문순옥;유주현
    • Microbiology and Biotechnology Letters
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    • v.6 no.2
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    • pp.65-73
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    • 1978
  • Naringinase extracted from the culture media of Aspergillus nidulans was purified, and the activity was proved to be stronger by 781 fold in the part of precipitation with ammonium sulfate, and column chromatography using DEAE-Sephadex A-25 and Sephadex G-100. Two fractions which had the same enzyme activity were isolated by the purification. Both fractions showed the highest enzymes activity under the reaction conditions of pH 5.0 and 40$^{\circ}C$. Molecular weight of fraction I and fraction II were estimated as 78,000 and 26,000 respectively. This indicated that fraction I would be trimer of fraction II. The enzyme was inhibited by glucose and rhammose, and the Km value was calculated to be 2.3${\times}$ 10$\^$-6/ g/ml.

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An Analysis on the Students' Understanding in Concept and Operations of Decimal Fraction (초등학생들의 소수 개념과 그 연산에 대한 이해도 분석)

  • Moon, Beomshik;Lee, DaeHyun
    • Journal of Elementary Mathematics Education in Korea
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    • v.18 no.2
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    • pp.237-255
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    • 2014
  • The purpose of this study is to investigate elementary school students' understanding the concept and operations of decimal fraction. The survey research was performed for this study. This survey was done by selecting 156 students. Questionnaire were made in five areas with reference to the 2007 revised mathematics curriculum. Five areas were the concept of decimal fraction, the addition, the subtraction, the multiplication and the division of decimal fraction. The results of such analysis are as follow: The analyzed result of understanding about concepts and operation of decimal fraction showed a high rate of correct answer, more than 85%. Students thought that multiplication and division of decimal fraction is more difficult than addition, subtraction, concept of decimal fraction. As the learning about concepts and operation of decimal fraction progress, the learning gap is bigger. Effort to reduce the learning deficits are needed in the lower grades. Mathematics is the study of the hierarchical. Learning deficits in low-level interfere with the learning in next-level. Therefore systematic supplementary guidance for a natural number and decimal fraction in low-level is needed. And understanding concepts and principles of calculations should be taught first.

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Hypoglycemic Action of the Fat Soluble Fraction of Panax Ginseng C.A. Meyer in Streptozotocin Induced Diabetic Rats (Streptozotocin 유발 당뇨병 쥐에서의 인삼 지용성분획의 혈당 강하작용)

  • 주충노;김선진
    • Journal of Ginseng Research
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    • v.17 no.2
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    • pp.101-108
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    • 1993
  • This study was made to understand a hypoglycemic action of the fat soluble fraction of Panax ginseng C.A. Meyer in streptozotocin induced diabetic rats by determining the activities of several enzymes related to carbohydrate and lipid metabolism as well as several blood component levels such as glucose and ketone bodies, and non-esterified fatty acids. Albino rats (Sprague Dawley, 170-200g, 3) were injected once with 70mg streptozotocinhg body weight intraperitoneally and fed with ordinary diet for 7 days, and then the fat soluble fraction (5 mg~20 mg/day/rat) was injected intraperitoneally once a day for three days to rats having high blood glucose level over 340 mg/100ml. After a final injection of the fat soluble fraction, rats u.ere starved for 16 hours followed by the analysis of blood serum and liver enzymes. It was found that increased levels of glucose, ketone bodies and free fatty acids in streptozotocin induced rats were decreased appreciably by administration of the fat soluble fraction. However, the amount of administered fat soluble fraction did not show any significantly different hypoglycemic action. Decreased activities of glucokinase, phosphofructokinase, pyruvate kinase, 6-phosphogluconate dehydrogenase and acetyl CoA carboxylase of the liver of streptozotocin induced diabetic rats were greatly modified suggesting that a hypoglycemic action of the fat soluble fraction was also appreciable as ginseng saponin fraction. We also compared a hypoglycemic action of the fat soluble fraction prepared from American ginseng and Chinese ginseng with that of Korean pain ginseng. 핀o significant difference of the hypoglycemic activity was observed between the above ginseng fat soluble fractions, suggesting that a study of the fat soluble fraction might be one of the most interesting subjects relating to diabetic hyperglycemia in the near future.

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Analysis and Critique of the Introduction of Decimal Fraction in Korean Elementary Mathematics (우리나라 초등학교 수학에서의 소수 도입에 대한 분석과 비판)

  • Kang, Hyun-Young;Park, Moon-Hwan;Park, Kyo-Sik
    • School Mathematics
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    • v.11 no.3
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    • pp.463-477
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    • 2009
  • Decimal Fraction with a significant meaning is being treated for long periods, from elementary school to high school. It is necessary to consider in a course of guidance about various aspects of decimal Fraction first of all in order that student understand well about the concert of it. If you overlook guidance of various means of decimal Fraction, Previously learned number system is limited understand of Decimal Fraction concept or meaning of Decimal Fraction limited to the one is difficult to calculate the Decimal Fraction, even can weaken understand of Real Number. Accordingly, in this study, we would like to separate meanings of the Decimal Fraction, focusing on the role and function of the Decimal Fraction in various situations used the Decimal Fraction. Based on this, we analyzed and criticized how to introduce the Decimal Fraction in elementary school textbooks according to the 7th curriculum.

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