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Studies on the Development of Natural Preservatives from Natural Products (전통식품 및 천연물에서 천연보존료 개발에 관한 연구)

  • Kim, Hee-Yun;Lee, Young-Ja;Hong, Ki-Hyoung;Kwon, Yong-Kwan;Lee, Ju-Yeun;Kim, So-Hee;Ha, Sang-Chunl;Cho, Hong-Yon;Chang, Ih-Seop;Lee, Chul-Won;Kim, Kil-Saeng
    • Korean Journal of Food Science and Technology
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    • v.31 no.6
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    • pp.1667-1678
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    • 1999
  • Certain parts of 190 kinds of medicinal herbs and 171 kinds of original materials of food were extracted by methanol. The extracts were tested their microbial inhibition activities against several food spoilage microorganisms, Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli, Saccharomyces cerevisiae, Candida albicans, Penicillium citrinum, Aspergillus flavus and Aspergillus niger. The methanol extracts of Cornus officinalis, Evodia officinalis, Glycyrrhiza glabra, Salvia miltiorrhiza. Schizandrae fructus, Coptidis rhizoma, aroma hop and bitter hop were shown inhibitory effect on certain species of gram(+) bacteria. Aroma hop and bitter hop were shown inhibitory effect on certain species of gram(-) bacteria. The methanol extract of Salvia miltiorrhiza exhibited a strong antibacterial activities. It was purified by solvent fractionation, silicagel column chromatography, prep. TLC, prep. HPLC. The purified active substance was identified as cryptotanshinone by EIMS, $1^H-NMR,\;{13}^C-NMR$ and DEPT. Cryptotanshinone showed a strong antibacterial activity against gram positive bacteria $(MIC\;:\;3.91{\sim}62.50\;{\mu}g/mL)$. Especially, this compound was the most strong activity against Bacillus subtilis $(MIC\;:\;3.91\;{\mu}g/mL)$.

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Extraction of Carotenoid from Phaffia rhodozyma by Combining Permeabilizing Methods and Pulsed Electric Fields Treatments (투과성 증진 방법과 펄스전기장의 병합처리에 의한 Phaffia rhodozyma로부터의 Carotenoid 추출)

  • Kim, Nam-Hoon;Shin, Jung-Kue;Lee, Seok-Hoon;Cho, Hyung-Yong;Pyun, Yu-Ryang
    • Korean Journal of Food Science and Technology
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    • v.31 no.6
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    • pp.1529-1535
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    • 1999
  • This study was done for the extraction of carotenoid from Phaffia rhodozyma in combination with PEF and other methods. PEF treatment conditions were $30{\sim}80\;kV/cm,\;100{\sim}1000\;Hz\;and\;100{\sim}1000\;{\mu}s$. In order to increase permeability of yeast cell wall, various methods such as freezing-thawing, mechanical treatment, solvents, permeabilizing agents, and yeast cell wall lytic enzyme were used before PEF treatment. The combination of PEF $(50\;kV/cm,\;300\;Hz,\;1000\;{\mu}s)$ and conventional methods such as solvent and freezing-thawing pre-treatment had no effects on the extraction of carotenoid pigments. The extent of extracted carotenoid by the PEF $treatment(50\;kV/cm,\;300\;Hz,\;1000\;{\mu}s)$ combined with yeast cell wall lytic enzyme and mechanical pre-treatment increased 52% and 69.8% more than the sum of that by each treatment, respectively. Permeabilizing agents, especially Tween 20 and capric acid, enhanced the extraction efficiency of carotenoid pigments from P. rhodozyma cells. These results indicated the feasibility for the continuous extracting carotenoid pigments from P. rhodozyma by PEF combined with other permeabilizing methods.

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Development of Analysis Method of Caffeine and Content Survey in Commercial Foods by HPLC (HPLC를 이용한 카페인의 분석법 개발 및 시판 식품중 함유량 조사)

  • Kim, Hee-Yun;Lee, Young-Ja;Hong, Ki-Hyoung;Lee, Chul-Won;Kim, Kil-Saeng;Ha, Sang-Chul
    • Korean Journal of Food Science and Technology
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    • v.31 no.6
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    • pp.1471-1476
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    • 1999
  • A simple and practical method for determination of caffeine in foods was developed. The analysis of caffeine was performed by reverse phase high performance liquid chromatography using a ${\mu}-Bondapak\;C_{18}$ column at isocratic condition with methanol-acetic acid-water(20 : 1 : 79) on UV detector at 280 nm. The clean-up and extraction of caffeine in samples were based on a simple pretreatment using a Sep-Pak $C_{18}$ cartridge. Recovery rates obtained with this method for cider, candy, cookie, milk, ice cream and persimmon leaf tea were 99.23%, 99.50%, 99.17%, 99.37%, 98.93% and 99.10% respectively. And the detection limit of caffeine was $0.1\;{\mu}g/mL$. With this method, the range of caffeine contents extracted from coffee, green tea, black tea, Oolong tea(tea bag), soft drinks, ice cream, milk and commercial confectionery were $3.38{\sim}37.50\;mg/g,\;16.30{\sim}26.10\;mg/g,\;10.80{\sim}16.65\;mg/g,\;11.25\;mg/g,\;0.06{\sim}0.11\;mg/g,\;0.04{\sim}0.44\;mg/g,\;0.04{\sim}0.39\;mg/g\;and\;0.10{\sim}1.80\;mg/g$, respectively. But caffeine was not detected in the other tea such as Acanthopanax sessiliflorum tea, Angelica gigas tea, Angelica tea, Arrow root tea, Duchu'ng tea, Dunggulle tea, Ganoerma lucidum tea, Ginger tea powder, Persimmon leaf tea, Ssanghwa tea and Cocoa mix powder.

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THE FOREIGN EXCHANGE RATE UNDER RATIONAL EXPECTATION (이성적(理性的) 기대하(期待下)의 환율행태분석(換率行態分析))

  • Yu, Il-Seong
    • The Korean Journal of Financial Management
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    • v.6 no.1
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    • pp.31-62
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    • 1989
  • By using deterministic dynamic models, we observe the behavior of the foreign exchange rate of a small open economy with rational expectation formation and different restrictions on the international economic integrations. First, an economy connected to the world by purchasing power parity and uncovered interest parity is studied in the next section. In both sections, financial assets available in the economy are domestic money and bonds. Stocks are added as a financial instrument in the next section, and real capital accumulation is also taken into account. Furthermore, the economy concerned there is fairly autonomous, and not directly governed by either purchasing power parity or uncovered interest parity. The expectation formation used throughout the whole paper is complete perfect foresight, which is the certainty version of rational expectation and free from any forecast errors. It is found that upon monetary expansion the short run depreciation of the foreign exchange rate is a fairly robust result regardless of the degree of the international economic integration, while it is not true for fiscal expansion. The expectation on the long run state significantly affects the short run response of the exchange rate. All of our models postulate that the current account should be balanced eventually. As the result, the short run behavior of the exchange rate is affected by the expectation on the long run balance and may well be a blend of the traditional flow view and modem asset view. The initial overshooting of the exchange rate is easily observed even in the fairly autonomous economy Furthermore, the initial overshooting is not reduced over time, but augmented for some time before it is eventually eliminated. As long as we maintain rational expectaion, introducing time delay in the adjustment of the foreign goods price to the foreign exchange rate does not make much difference.

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Comparison of Liver, Kidney, Bone Metal Concentration in OhJeokSan-Treated Rats (오적산(五積散)을 투여한 흰쥐의 간장, 신장, 골중 금속농도 비교에 관한 연구)

  • Park Chul-Soo;Lee Sun-Dong;Park Hae-Mo;Park Yeong-Chul
    • Journal of Society of Preventive Korean Medicine
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    • v.6 no.2
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    • pp.66-85
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    • 2002
  • Traditional herbal medicine is used extensively among the Korean populations, and other Asian countries employ similar therapies as well In recent years, extensive focus was laid on adulteration of the herbal medicine with heavy metals. This may be mainly due to a soil contamination by an environmental pollution. The objective of this study is to identify the contents of various heavy metals in the blood from OhJeokSan-Decoction (OD) treated-rats. For this study, 13 kinds of metals including essential and heavy metals, i.e. Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se and Zn were analyzed by a slight modification of EPA methods and the following results are obtained. ; 1. There is no significant difference between the OD-treated groups and control group in liver, kidney, bone, brain, weight, food intake. 2. The amount of each metal analyzed in the liver are as follows; Al ; $0.235{\sim}4.215mg/kg$, As ; $0.103{\sim}0.461mg/kg$, Cd ; $0.005{\sim}0.010mg/kg$, Co ; $0.017{\sim}0.046mg/kg$, Cr ; $0.137{\sim}0.403mg/kg$, Cu ; $1.736{\sim}4.827mg/kg$, Fe ; $54.472{\sim}381.447mg/kg$, Hg ; not detected, Mn ; $1.159{\sim}2.803mg/kg$, Ni ; $0.007{\sim}0.095mg/kg$, Pb ; not detected, Se ; $0.682{\sim}1.887mg/kg$, Zn ; $10.213{\sim}26.119mg/kg$, by groups, respectively. In control and other experimental group, several metal (Co, Cu, Mn, Zn, As, Cr) has a significant difference, but in experimental I and other experimental II, III, IV, V groups, there are no significant difference. 3. The amount of each metal analyzed in the kidney are as follows; Al ; $1.712{\sim}31.230mg/kg$, As ; $0.062{\sim}0.439mg/kg$, Cd ; $0.010{\sim}0.062mg/kg$, Co ; $0.000{\sim}0.101mg/kg$, Cr ; $0.125{\sim}0.636mg/kg$, Cu ; $3.385{\sim}12.502mg/kg$, Fe ; $41.148{\sim}99.709mg/kg$, Hg ; $0.000{\sim}0.270mg/kg$, Mn ; $0.433{\sim}2.301mg/kg$, Ni ; $0.000{\sim}0.221mg/kg$, Pb ; $0.000{\sim}0.584mg/kg$, Se ; $0.540{\sim}1.600mg/kg$, Zn ; $8.775{\sim}17.060mg/kg$, by groups, respectively. The concentration of Cu, Se, Cr, and Hg are variated significantly in control and other experimental group, and Cu, Se, Cd, Cr are variated significantly in experimental I and other experimental II, III, IV, V groups. 4. The amount of each metal analyzed in the bone(tibia and fibula) are as follows; Al ; $9.557{\sim}119.464mg/kg$, As ; $0.139{\sim}12.250mg/kg$, Cd ; $0.000{\sim}0.295mg/kg$, Co ; $0.022{\sim}0.243mg/kg$, Cr ; $0.239{\sim}1.999mg/kg$, Cu ; $0.000{\sim}2.291mg/kg$, Fe ; $240.249{\sim}841.956mg/kg$, Hg ; $0.000{\sim}0.983mg/kg$, Mn ; $0.214{\sim}7.353mg/kg$, Ni ; $5.473{\sim}11.453mg/kg$, Pb ; $0.000{\sim}8.502mg/kg$, Se ; $0.000{\sim}3.005mg/kg$, Zn ; $61.158{\sim}195.038mg/kg$, by groups, respectively. The concentration of Se, Cd are variated significantly in control and other experimental groups, and Se is variated significantly in experimental I and other experimental II, III, IV, V groups. 5. Exceptionally several metal concentration is increased or decreased. but there is no significant harmful difference of metal concentration in the liver, kidney and bone, from the OD-treated-rats compared to those of the control group even if higher dosage($1{\sim}8$ times dosage of person) of OD was administered. Thus, it is expected that the herbal decoction in the traditional herbal medicine would not lay any burden on the body and the heavy metal toxins would not affect our physiological system. However, other kinds of herbal treatment, such as i.v. and i.p. should be considered in terms of metal toxicity in the body since the level of certain metal.

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Antioxidant Activities and Quality Characteristics of Germinated Rough Rice Tea according to Roasting Temperature, Time and Leaching Condition (볶음 조건 및 침출 조건에 따른 발아 벼차의 항산화 활성 및 품질 특성)

  • Lee, Sang-Hoon;Lee, Youn-Ri;Hwang, In-Guk;Woo, Koan-Sik;Kim, Kyoung-Ho;Kim, Kee-Jong;Jeong, Heon-Sang
    • Korean Journal of Food Science and Technology
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    • v.41 no.4
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    • pp.386-391
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    • 2009
  • To verify the possibility of manufacturing a germinated rough rice tea, germinated rough rice was roasted at 200, 220, and $250^{\circ}C$ for 10, 20, and 30 min. The treated rice powder was then put into tea bags and leached for 1, 3, and 5 min, after which their antioxidant, physicochemical, and sensory characteristics were compared. The total polyphenol content and 2,2'-Azino-bis-(3-ethyl benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities of the germinated rough rice tea increased as the roasting temperature increased as well as in response to increased roasting and leaching times. Furthermore, the greater the roasting temperature, roasting time, and leaching time, the greater the increase in total soluble solid contents. Moreover, the turbidity and browning index of the germinated rice tea rose as the roasting temperature, roasting time, and leaching time increased. Additionally, the pH tended to decrease as the roasting temperature, roasting time, and leaching time increased. Evaluation of the sensory characteristics of the germinated rice tea revealed that the formation of a Maillard reaction product in the course of heating the rice added a unique flavor, which led to increase preference for the color, flavor, and taste, and therefore, the overall preference.

Appearance Rates of Several Substances into Cerebrospinal Fluid of Histamine-treated Rabbits (히스타민 투여시 토끼 뇌척수액으로의 물질 출현율)

  • Kim, Won-Shik;Shin, Dong-Hoon
    • The Korean Journal of Physiology
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    • v.2 no.2
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    • pp.21-31
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    • 1968
  • The appearance rates of antipyrine and urea into cerebrospinal fluid from blood were studied in the rabbits which were in the state of hypotension and of high permeability in the capillary beds following injection of histamine. The alteration in the distribution of electrolytes among various compartments of the brain and the permeability characteristics in the blood-cerebrospinal fluid barrier were also observed. Adult male rabbits, weighing around 2 kg, were used. Twenty four rabbits were divided into 3 groups. Besides the control group, histamine treated rabbits were categorized into 2 groups. $H_1$ consisted of the rabbits showing moderate responses to histamine and ranging from 62 to 80 mmHg in their mean anterial blood pressure. The animals which belong to $H_2-group$ showed severe responses to histamine and the mean anterial blood pressures dropped to 30-50 mmHg. Animals were anesthetized with nembutal, 30mg/kg i.v. The mean arterial blood pressure was read by means of the mercury manometer connected to the femoral artery. The animals, treated with histamine, were kept in hypotensive state at least for 40 minutes before the administration of the test-substances. The test-substances, 300 mg of urea and 200 mg of antipyrine, were dissolved in 3 ml of distilled water and were injected into the ear vein of the rabbit. After 10 minutes elapsed arterial blood sample was taken from the femoral artery and cerebrospinal fluid from the cisterna magna. Brain tissues were also analysed with respect to electrolytes in order to observe the disturbances in the electrolytes balance as well as in the function of the central nervous system. The results obtained were as follow: 1. The ratio of antipyrine concentration in cerebrospinal fluid to that of arterial blood plasma, that was the distribution ratio, was close to unity, revealing a well established equilibrium between the compartments of blood and cerebrospinal fluid in 10 minutes. In other words, there was no diffusion barrier with regard to antipyrine. The ratios over unity which were frequently seen in the histamine treated animals were attributable to the early penetration of the substance into the cerebrospinal fluid. 2. The appearance rates of urea into the cerebrospinal fluid in the histamine treated rabbits were higher in comparison with those of in the control animals. The increasing tendency in the rates was particularly remarkable in the $H_2-group$, showing the enhanced penetration of urea across the boondary. 3. In the htisamine treated $H_2-group$ the concentration of potassium in the blood plasma and cerebrospinal fluid well exceeded the control values and showed 8.5 and 9.0 mEq/l in average, respectively. Simultaneous drops in the brain tissue water were noticed, suggesting the leakage of intracellular potassium. 4. There was a coincidence in the rising pattern of potassium in the blood plasma and in the cerebrospinal fluid of $H_2-group$ and at least partial removal of the blood-cerebrospinal fluid barrier with respect to potassium was suggested in these animals. 5. The concentration of sodium in the blood plasma or in the cerebrospinal fluid showed no significant changes following histamine injection. However, sodium in the brain tissue revealed slight elevation in the histamine treated groups. 6. The ratios of the concentrations of potassium to those of sodium, [K]/[Na] in the brain tissues, were 1.92 in the control 1.82 in the $H_1$ and 1.52 in the $H_2-group$, respectively. The marked drop in the $H_2-group$ might represent neural dysfunction in the extremely hypotensive rabbits.

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Electron Microscopic Studies on Olfactory Bulbs in the Vertebrates by Phylogenetics (계통발생에 따른 척추동물의 뇌후구에 대한 전자현미경적 연구)

  • Choi, W.B.;Chung, Y.H.;Seo, J.E.
    • Applied Microscopy
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    • v.15 no.2
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    • pp.31-68
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    • 1985
  • Authors are trying to unveil the ultrastructural organization of olfactory bulb, which has been summerized under light microscopic level or communicated only in some detail in different view point until now. For the critical point of view, since the phylogenetical approach will give the ultimate value in the correlative study between structural and functional bases (Brodal, 1969), the present study was carried out light and electron microscopic analyses of the structures of the neurons and synaptic organizations in olfactory bulbs from different animals in phylogenetical scale. We selected each one species from five animal classes: the house rabbit(Oryctolagus cuniculus var. domesticus [Gmelin]) from Mammalia, the domestic fowl (Gallus gallus domesticus Brisson) from Aves, the viper (Agkistrodon hylys [G.P. Pallas]) from Reptilia, a frog (Bombiana orientalis Boulenger) from Amphibia and the crussian carp (Carassius carassius [Linne]) from Pisces. For light microscopic study, samples were fixed in 10% formalin and paraffin sections were stained with hematoxylin-eosin. For the electron microscopic study, the tissues were fixed by perfusion through the heart or immersion with 1% paraform-aldehyde-glutaraldehyde mixture (phosphate buffer, pH 7.4), and final tissue block trimmed under dissecting microscope were osmicated (1% OsO4), they were embedded in Araldite or Epon 812, and ultrathin sections were made by LKB-V ultratome following the inspection of semi-thin sections stained with toluidine blue-borax solution. Ultra-thin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100CX electron microscope. We have summerized our morphological analyses as follows: 1. The olfactory bulb of rabbit, viper and frog shows the eight layers of fila olfactoria, glomerular, external granular, external plexiform, mitral cell, internal plexiform, internal granular, medullary but domestic fowl shows the five layers of glomerular, fibrillar, mitral, granular and medullary and the three layers of fibrilla, glomerular and medullary in crussian carp. The sharpness of demarcation between the layers shows deferential tendency according to phylogenetical order. 2. Mitral cells of vertebrate have large triangular or oval shape with spherical nuclei which contain not so much chromatin. The cytoplasm contains numerous cell organelles, of which Nissl's bodies or granular endoplasmic reticula arranged as parallel strands. Development of granular endoplasmic reticula were declined as the phylogentical grade is going lower. 3. Tufted cells of all animal are mostly spindle or polygonal contour and contain oval nuclei which located in periphery of cytoplasm. The nuclei of rabbit, fowl, viper and frog has relatively space chromatin, but a nucleus of crussian carp contain irregularly aggregated chromatin in karyoplasm. Their cytoplasmic volume and cell organelle contents are in between those of mitral cell and granular cell. They contain moderate amount of mitochondria, granular endoplasmic reticula, a few Golgi complex, polysomes, lysosome, etc. 4. Granule of cells of all the vertebrate amimals studied exhibit similar features; cells and their dense nuclei show spherical or oval contour, and they have the thin rim of cytoplasm which contain only a few cell organelles. 5. In rabbit, the soma of mitral cells were in contact with boutons with two types of synaptic vesicles, that is, round and flat vesicles, especially flat vesicles in boutons were showing reciprocal synapses. However, in domestic fowls, vipers, frogs and crussian carps, there were found boutons showing only spherical synaptic vesicles. 6. The boutons containing round synaptic vesicles were made contact with the some of tufted cell of olfactory bulb in the rabbits, fowls, vipers and frogs, but no synaptic boutons were observed in soma of tufted cells in crussian carps. In the frogs, there were observed dendrites were contact with the soma of tufted cells. 7. In the neuropils of plexiform, granular and glomerular layers olfactory bulbs in the vertebrate, the synapses were axo-large dendrites, axo-median and small dendrites, dendrodendritic, and axo-axonal contacts. However, in the neuropil of crussian carps, synapses were observed only in glomerular layer.

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Comparison of Maternal Fatty Acid Intake and Fatty Acid Composition of Serum Phospholipids Between Singleton and Twin Pregnancies (단태아와 쌍태아 모체의 임신 분기별 지방산 섭취와 혈청 인지질 지방산 조성 비교)

  • Kwon, Seul-Ki;Lim, Soo-Jeoung;Shin, Joong-Sik;Jang, Sung-Hee;Ahn, Hong-Seok
    • Korean Journal of Community Nutrition
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    • v.13 no.4
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    • pp.555-564
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    • 2008
  • Essential fatty acids are important essential nutrients during pregnancy. The objective of this study was to compare fatty acid composition of serum phospholipids and essential fatty acid intakes between Korean pregnant women with a single baby and Korean pregnant women with twins. A total of 116 pregnant women who had maintained their health without any symptoms of pregnancy complications participated in the study. The subjects consisted of 57 women of singleton pregnancy and 58 women of twin pregnancy at the 1st, 2nd, or 3rd trimester of pregnancy. A 24-hour dietary recall was administered to each subject to obtain dietary information. The mean ages of the singleton pregnancy group and the twin pregnancy group were 31.44 years and 32.27 years, respectively, and the mean height values were 161.86 cm and 160.64 cm, respectively. The mean daily energy intakes in the singleton pregnancy group were 1639.95 kcal, 1904.71 kcal, and 1882.82 kcal for the 1st, 2nd, and 3rd trimester group, respectively. The mean daily energy intakes in the twin pregnancy group were 1745.99 kcal, 2203.46 kcal, and 2092.26 kcal for the 1st, 2nd, and 3rd trimester group, respectively. There were no significant differences in the mean fatty acid intakes by the type of pregnancy (i.e., singleton vs. twins) and the stage of pregnancy (i.e., 1st vs. 2nd vs. 3rd trimester). However, the mean total fatty acid intake of those at the 1st trimester among the singleton pregnancy group tended to be higher than that of those at the 1st trimester among the twin pregnancy group. Such a trend seemed to be retro-versed. That is, the mean total fatty acid intakes of the twin pregnancy group were higher compared to the singleton pregnancy group for the 2nd and 3rd trimester group. The LA and total n6 concentrations of serum phospholipids of the singleton pregnancy group were significantly higher as the gestational age increased(p<0.05). The $\alpha-LNA$(p<0.05), EPA(p<0.05), and total n3(p<0.001) concentrations of serum phospholipids of the twin pregnancy group were significantly lower as the gestational age increased. The $\alpha-LNA$ concentrations of serum phospholipids in the singleton pregnancy group at the 3rd trimester were significantly higher than that in the twin pregnancy group at the same trimester(p<0.05). The serum phospholipids levels of AA and DHA of the twin pregnancy group were generally higher compared to those of the singleton pregnancy group. Particularly the differences reached at the level of statistical significance for those at the 1st trimester(p<0.01). It is concluded that the study findings imply that fatty acid metabolism may meaningfully differ by the type and stage of pregnancy. Future research needs to be conducted to more elucidate grounding etiology and possible roles of dietary fatty acid intake levels in relation to the study findings.

A Study on the Bed Climate and the Physiological Responses in Sleep. - On Ondol Environment - (수면시 침상기후와 인체생리반응에 관한 연구 -온돌환경을 중심으로-)

  • Kim Myung Ju;Choi Jeong Wha
    • Journal of the Korean Society of Clothing and Textiles
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    • v.15 no.2 s.38
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    • pp.77-87
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    • 1991
  • The purpose of this study were to investigate the bed climate and the physiological responses in sleep on the traditional Korean floor heating system called Ondol. Ondol has been the most widely used heating system in Korea, yet there has been a no systematic studies examined its environmental effects on human body. Experimental room was constructed to match the typical thermal environment of Ondol. (floor surface temperature; $32\~33^{\circ}C$, air temperature; $22.5{\pm}1.0^{\circ}C$, relative humidity; $64.0{\pm}4.0\%$RH, air velocity; 0.25 m/sec.) Three different combinations of bedclothes were chosen for the experiment based on the study results showing that they were the most widely used types in Korea. Type 1 was the combination of a cotton-padded mattress with a cotton-padded Korean style blanket. Type 2 was a cotton-padded mattress with a cotton-guilted Korean style blanket. Type 3 was a cotton-padded matless with a polyacryl blanket. Thermal resistance of each of these combina-tions in the bedclothes was measured using thermal manikin. Two adult female was chosen for the seven hour sleeping experiment which was known to be the average sleeping hours of Korean adult female. The bed climate was measured with the temperature under the mattress, the surface temper-ature of the mattress, and the air temperature and the relative humidity of the space between the mattress and blanket. The skin temperature, rectal temperature of the subjects and the bed climate were measured eight times, one hour before the experiment and every hour during the experiment. The weight loss and the subjective sensation were measured for the each subjects before and after the experiment. The procedure was repeated twice with two subjects and three types of bedclothes, yielding twelve combinations of results. The results were as follows; 1. With the surface temperature of $32\~33^{\circ}C$ of Ondol, air temperature was $22.5{\pm}1.0^{\circ}C$ with $64.0{\pm}4.0\%$ RH. The bed climates were $39.2{\pm}40.8^{\circ}C$ under the mattress, $35.3\~36.2^{\circ}C$ on the mattress, and $26.9\~32.0^{\circ}C$ with $56.0\~71.3\%$ RH between the mattress and the blanket. 2. Mean skim temperature during sleep was 34.2"C with local skin temperature of $34.0\~35.5^{\circ}C$. The skin temperatures of abdomen, thigh, foot were higher than the other parts of the body. 3. The skin temperature of chest, thigh, leg and back varied significantly according to the combinations of bedclothes. With the cotton-padded blanket, the skin temperature was the highest, while with the cotton-guilted blanket showed lowest. 4. Examining the relationship between the mean skin temperature and the local skin temper-ature, the chest temperature showed the highest correlation with the former. Therefore, the chest temperature can be recommended to represent the skin temperature in measuring the bed climate. 5. The subjective bed climates were $39.0\~40.4^{\circ}C$ under the mattress, $35.2\~35.9^{\circ}C$ on the mattress, $29.8\~31.6^{\circ}C$ with $56.8\~68.4\%$ RH between the mattress and blanket. In sum, from this experiment we not only obtained the reliable value of bed climates on Ondol, but also showed that the bed climates and the physiological responses were affected differently according to the materials of bed clothes.

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