• Title/Summary/Keyword: Alkali

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A Study on the Molecular Weight Distribution of Starch (전분의 분자량 분포도에 관한 연구)

  • Kim Kyeong-Yee
    • Food Science and Preservation
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    • v.11 no.4
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    • pp.496-502
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    • 2004
  • Purified acorn starch was obtained from alkali precipitation method. Acorn amylose and acorn amylopectin were fractionated from purified acorn starch by butanol improvement method. Gel permeation chromatography (GPC) was used to measure molecular weight distribution of acorn starch, acorn amylose, acorn amylopectin and corn starch, corn amylose, corn amylopectin. GPC measurement diagrams were obtained by each retention time. And then, we used DMSO and DMF as solvent, pullulan as standard material. We calculated the Number-average molar mass (Mn), Weight-average molar mass (Mw) and polydispersity from molecular weight distribution of each sample. As a result of estimating molecular weight using GPC, Mw of amylose has small value than Mw of amylopectin. From this fact, the molecular structural aspects of amylose and amylopectin were predicted and it was in good agrement with the tendency of polydispersity by GPC. The polydispersity of starch had big value than amylose and amylopectin, from this result, it might be known that the range of molecular weight appeared broad by heterogeneous properties of two components. The viscosity of purified acorn starch, amylose, amylopectin seperated from acorn starch, was decreased by increasing the shear rate and raising the temperature exponentially. Acorn starch solutions exhibited pseudoplastic power law fluid behavior.

Changes in Antioxidative Activity and Total Polyphenols of Crude and Defatted Grape Seed Extract by Extraction Condition and Storage (포도종자의 처리별 추출조건 및 저장에 따른 항산화활성 및 총페놀함량의 변화)

  • Kim Young-Kuk;Lee Hyeon-Yong;Oh Deog-Hwan
    • Food Science and Preservation
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    • v.11 no.4
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    • pp.455-460
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    • 2004
  • This study was conducted to determine the yield, free radical scavengering effect and total phenol contents of various solvent fractions on the crude and defatted grape seed extract during storage. The optimal condition for the extraction yield, free radical scavengering effect and total phenol contents was $90\%$ ethanol for 6 hour at $70^{\circ}C$. The extraction yield for crude and defatted grape seed at optimal condition was $8.9\%\;and\;9.16\%$, respectively. Also, the strongest free radical scavengering effect with $41.52\;{\mu}g/mL$ was observed in $95\%$ ethanol of defatted grape seed extracted for 6 hour at $70^{\circ}C$. Similar result was observed in total phenol contents of defatted grape seed. The ethyl acetate fraction obtained from ethanol extract of defatted grape seed showed the strongest RC50($12.35\;{\mu}g/mL$) compared to other organic fractions. Free radical scavengering effect of crude and defatted grape seed extracts treated with alkali condition(pH 10) was reduced compared to that of acidic condition(pH 2) during storage far 1 month at $50^{\circ}C$. Overall, more stronger free radical scavengering effect and higher total phenol contents in defatted grape seed extracts was observed than that of crude grape seed.

Cleaning and Storage Effect of Electrolyzed Water Manufactured by Various Electrolytic Diaphragm (격막 방식에 따라 제조한 전해수의 세척 및 보관 효과)

  • 김명호;정진웅;조영제
    • Food Science and Preservation
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    • v.11 no.2
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    • pp.160-169
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    • 2004
  • This study was carried out to investigate the efficacy of electrolyzed water manufactured with or without diaphragm on sterilization and preservation of cut-celery and shelled raw oyster. In cut-celery, total viable cell count and coliform group in the treatment of electrolyzed water were decreased to about 1/200∼1/1,000 level and about 1/100 level comparing non-treated ones. But moisture content, pH, hardness, vitamin C and residual chlorine content were showed a little difference among treatments up to 10 days at 10$^{\circ}C$. L and a color values were gradually increased in all treatments, and color differences($\Delta$E) were remarkable between treatment and untreatment sample. In overall acceptability, cut-celery treated with electrolyzed water showed somewhat higher score than that of other ones treated with tap water and 100 ppm NaClO solution until 5 days of storage. After 48 hours of storage, it was showed that VBN, total viable cell count and coliform count of shelled raw oyster treated with electrolyzed alkali water produced by non-diaphragm system are lower by about 3 mg%, 1∼2 log cycle and 2 log cycle respectively than that of ones treated with sea water. Total viable cell count of shelled raw oyster just after treatment was lower by about 1 log cycle than that of ones treated with sea water, and any significant increment was not found after 24∼48 hours of storage.

Postharvest Changes in Quality and Biochemical Components of Leaf Lettuce (상치의 수확후(收穫後) 품질(品質) 및 성분변화(成分變化))

  • Kim, Seong Yeol;Hong, Young Pyo;Choi, Woo Young
    • Korean Journal of Agricultural Science
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    • v.12 no.1
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    • pp.128-138
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    • 1985
  • This study was conducted to elucidate the shelf-life and quality changes in relation to biochemical components in leaf lettuce (Lactuca sativa L.). The shelf-life of leaf lettuce at room temperature was 2 to 3 days. But it was extended to 3 weeks by packaging in a 0.01 mm thick polyethylene film sack when stored at $3^{\circ}C$. The ascorbic acid contents of fresh leaf lettuce was 25 mg per 100 gram fresh weight. The acid at room temperature was almost destroyed after 4 days storage. But the contents of ascorbic acid at $3^{\circ}C$ maintained about 50 to 60% of the initial level in packaging of polyethylene film sack after 8 days storage. The content of chlorophyll was greatly decreased at room temperature but no significant changes were found at $3^{\circ}C$. The changes of total sugar and reducing sugar contents during storage were not very different between treatments. The contents of alkali soluble protein and free amino acid gradually increased in the treatments of polyethylene film sack packaging during storage in general, but the contents decreased after the increase in control treatment. Nucleic acid content, peroxidase and polyphenoloxidase activities were measured and discussed in relation to the leaf senescence.

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Chemical Composition and Biological Activities of Immunostimulants Purified from Alkali Extract of Poria cocos Sclerotium (복령 균핵의 알칼리추출물에서 정제한 면역활성 증강물질의 작용과 화학구성)

  • Rhee, Sang-Dal;Cho, Soo-Muk;Park, Jeong-Sik;Han, Sang-Bae;Jeon, Young-Jin;Kim, Hwan-Mook;Kim, Gwang-Po
    • The Korean Journal of Mycology
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    • v.27 no.4 s.91
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    • pp.293-298
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    • 1999
  • An one percent sodium carbonate extract prepared from sclerotia of Poria cocos activated the proliferation of the T lymphocytes as measured by mixed lymphocyte responses(MLR). The active fraction, PCSC22, was isolated from an one percent sodium carbonate extract by a combination of fractionation procedures, including ethanol precipitation and chromatographies on column of DEAE-cellulose and Sephadex G50. Carbohydrate and peptide contained in PCSC22 were 78 : 22% in ratio. On employing gel filtration high performance liquid chromatography, PCSC22 exhitited a homogeneous peak with an average molecular weight of 8 kDa. The sugar moiety of PCSC22 was composed with mannose (92%), galactose (6.2%) and arabinose (1.3%), which might be indicated as heteromannan. Fifteen amino acids were found in peptide moiety of the polysaccharide and aspartic acid, serine, and valine were major components. PCSC22 activated the primary proliferation of T lymphocytes measured by mixed lymphocyte responses, the antibody production of the B lymphocytes and the secretion of nitric oxide from macrophage cell line, RAW264.7.

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In vitro Study on the Functionality in Digestive Tract of Chitin and Chitosan from Crab Shell (게껍질 Chitin 및 Chitosan의 소화관내 기능성에 관한 in vitro 연구)

  • Chang, Hyun-Joo;Jeon, Dong-Won;Lee, Su-Rae
    • Korean Journal of Food Science and Technology
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    • v.26 no.4
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    • pp.348-354
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    • 1994
  • Chitin and chitosan samples prepared from crab's shells under different conditions were compared for their physicochemical properties; and functionality in gastrointestinal tract by in vitro test. Their bulk density was in the range of $127{\sim}208\;mg/ml$, and their viscosity was $80{\sim}581\;cP$ in 0.1 chitin and $80{\sim}3,670\;cP$ in 0.5% chitosan solution, showing a wide variation. The degree of deacetylation in chitosan samples as determined by IR spectral analysis was relatively high, showing $81{\sim}93%$. At the same alkali concentration and reaction temperature, a longer reaction period gave an increased degree of deacetylation and lower viscosity. The water holding capacity of chitic substance became greater at higher soaking temperature; chitosan D at $37^{\circ}C$ showed the greatest value. Chitic substance with lower bulk density showed the higher water holding capacity. The retardation effect toward glucose absorption was higher in critic substances of lower density and higher water holding capacity; chitosan D showed the highest value of 38%. The retardation index toward bile acid absorption after 1 hour dialysis was $15{\sim}34%$ in chitic substances, 39% in pectin and 9% in cellulose. The retarding effect showed the highest value of 34% in chitosan D at 3% concentration.

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Deterioration Analysis and Source Area on Rock Properties of the Seokgatap Pagoda in the Bulguksa Temple, Korea (불국사 석가탑의 풍화훼손도 분석 및 기원암의 산지추정)

  • Lee, Myeong-Seong;Lee, Chan-Hee;Suh, Man-Cheol;Choi, Seok-Won
    • 한국문화재보존과학회:학술대회논문집
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    • 2004.10a
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    • pp.15-24
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    • 2004
  • The Seokgatap pagoda composed of mainly alkali granite and other minor pink-feldspar granite, fine-grained granite, granodiorite, diorite, gabbro, and tuff. Despite the small loss and damage derived from joints, its peel-off and exfoliation are serious enough to cause the heavy deterioration on the stone surface. The chemical and petrological weathering has partly replaced the original rock-forming minerals with clay minerals and iron oxyhydroxides. Based on the petrogenesis, rock materials of the pagoda is very similar to rocks of Dabotap pagoda and the Namsan granite in the Gyeongju. The central fart of the pagoda has sunken highly, which caused all the corners to split and the structural transformation to become worse. The reverse V-shaped gaps between the materials have broken stones filled in a coarse way. The iron plates inserted between the upper flat stone laid on other stones and tile pagoda body in the north and east side has been exposed in the air and corroded, discoloring of the adjacent stones. The overall diagnosis of the Seokgatap pagoda is the deteriorated functions of the stone materials, which calls for a long-term monitoring and plans to reinforce the stone surfaces. But the main body including the pagoda roof stone needs washing on a regular basis, and the many different cracks should be fixed with glue by using the fillers or hardeners designed for stone cultural properties after removing the cement mortar. In case of the replacement of the stone materials with new stones, it's necessary to examine the pagoda for the center of gravity and support intensity of the materials. The structural stability of the pagoda can be attained by taking a reinforce measure in geotechnical engineering and making a drainage. The ground humidity, which has aggravated weathering and structural instability, should be resolved by setting up a humidity reduction facility. The contamination of lichens and bryophyte around the pagoda and on the surface is serious. Thus biochemical treatments should be given too in order to prevent further biological damages and remove the vegetation growing on the discontinuous planes.

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Weathering and Deterioration Diagnosis for Conservation Sciences of Stone Pagoda in the Bunhwangsa Temple,Gyeongju, Korea (경주 분황사 모전석탁의 암석학적 풍화와 보존과학적 훼손도 진단)

  • Yi, Jeong-Eun;Lee, Chan-Hee;Lee, Myeong-Seong;Kim, Young-Taek
    • 한국문화재보존과학회:학술대회논문집
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    • 2004.10a
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    • pp.92-100
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    • 2004
  • The host rocks of brick-shaped stone pagoda in the Bunhwangsa temple are lots of kinds andesitic rocks, which has gone through mechanical and chemical weathering. As the overall observation, the pagoda is serious damages by air pollutants, and the northeast parts show the much advanced state of turning white, while the southeast parts are heavily cracked in the materials. The rocks of brick-shaped pagoda body are in a relatively stable condition of weathering and damage except for the abrasion and cracks of the corners. The rocks of the pagoda roof suffer from more symptoms including multiple peel-offs, exfoliation, cracks forming round lines, and falling off stone pieces. The pagoda roof rocks are dominated by the thriving leafy lichens and mosses, especially, there are higher plants (selaginella involvens, dandelions) taking root actively between the brick stones and content mortar. There are even light gray precipitates like stalactites between the rocks of the body, In particular, the 1st and 2nd floor in the east side and the body parts in the north side are the most serious. Their major minerals are calcite, gypsum and clay minerals. The rocks of the stylobate and the tabernacle in all the four directions are composed mainly of granitic rocks. The materials consisting of the tabernacles show the severe splits and distortion, which causes the structural instability. The stylobate rocks are heavily contaminated by some weeds with the often marks of inorganic contamination by secondary hydroxides. The central part of the east stylobate has been sinking, while that of the 1st floor west stylobate is protruded nesting a line of cracks. Accordingly, the inside of the tabernacle is always humid with the constant introduction of rainwater. The stone lion standing in the southeast and northeast side are alkali granite, while that in the southwest and northwest lithic tuff. Each of the stone lion also coated with various colored lichens, mosses, algae, bacteria and bryophyte. The external materials of the pagoda have deteriorated the functions of the rocks and made the loss, falling off, and biological contamination even worse due to the surface weathering. Thus it's urgent to come up with scientific restoration and conservation measures through clinical tests.

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Behavior Interpretation of Discontinuity for Conservation Treatment of Standing Sculptured Buddha at the Yongamsa Temple, Korea (옥천 용암사 마애불의 보존관리를 위한 불연속면의 거동특성 해석)

  • Lee, Chan-Hee;Jeong, Yeon-Sam;Kim, Ji-Young;Yi, Jeong-Eun;Kim, Sun-Duk
    • 한국문화재보존과학회:학술대회논문집
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    • 2004.10a
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    • pp.81-91
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    • 2004
  • The host rock of standing sculptured Buddha in the Yongamsa temple was macular biotite granite, which has gone through mechanical and chemical weathering. The principal rock-forming minerals are quartz, plagioclase, alkali feldspar, and biotite, the last two of which have been transformed into clay minerals and chlorite due to weathering processes. The bed rock around the Buddha statue is busily scattered with steep inclinations that are almost vertical and discontinuous planes with the strikes of $N8^{\circ}E$. The major joints have the strikes of N4 to $52^{\circ}W$ and N6 to $88^{\circ}E$ and the dips of 42 to $89^{\circ}$. Especially thee development of the joints that cross the major joints causes tile structural instability of the rock. The host rock of the Buddha image is separated into many different rock masses because of the also many different discontinuity, which group accounts for about $12{\%}$ of the rock. Thus it's estimated that the bed rock has not only plane and toppling failure but also wedge failure in all the sides. Since the earth pressure and the inclination pressure are imposed on the body of the Buddha in the basement rock, it's urgent to give a treatment of geotechnical engineering for the sake of its structural stability. The parts where serious fractures are seen should receive the hardening process using the fillers for stones. It's also necessary to introduce a landfill liner system in order to reduce the ground humidity. The rock surface of the Buddha statue are partly contaminated by lichens and bryophyte. The joints have turned into earth, which promotes the growth of weeds and plant roots. Thus biochemical treatments should also be considered to get rid of the vegetation along the discontinuous planes and prevent further biological damages.

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Deterioration Assessment and Structural‐Reinforcement of Stone Lantern of the Four Guardian Kings in Beopjusa Temple, Boeun (보은 법주사 사천왕석등의 비파괴 훼손도 평가 및 구조보강)

  • Choie, Myoungju;Lee, Myeong Seong;Jun, Yu Gun;Lee, Mi Hye;Kim, Yuri;Ha, Jun Kyeong
    • Journal of Conservation Science
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    • v.33 no.1
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    • pp.25-33
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    • 2017
  • The stone lantern of the four guardian kings in the Beopjusa temple at Boeun was mainly made of biotite granodiorite consisting of porphyritic-textured potassium feldspar and included in ilmenite series. A base stone made of alkali granite was buried, after founded its place during an earlier restoration process. Cracking and break out are noticeable on this object. In addition, discoloration, salt crusting, and epiphytes were observed. The lantern was vulnerable in terms of physical and structural stability caused by cracking in the front and back of the light chamber and in the non-horizontal direction. According to the conservational condition of the stone lantern, structural reinforcement was carried out based on calculations, including those on the position, size, and anchor length of the titanium stiffener. Chemical and biological pollutants were washed off without damage to the surface of the stone material. Oxygenated iron pieces were replaced with titanium. Ethyl silicate was applied to the surface of the lantern for consolidation and smooth drainage.