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Production of Itaconic Acid by Various Immobilization Methods (다양한 고정화 방법에 의한 이타콘산 생산)

  • 김승욱;박승원;이진석
    • Microbiology and Biotechnology Letters
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    • v.22 no.6
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    • pp.646-650
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    • 1994
  • Aspergillus terreus NRRL 1960 was immobilized on various alginate gel beads, Celites, and polyurethane foam cubes, and the comparisons were made for the production of itaconic acid according to the types and sizes of each carrier. The levels of itaconic acid produced from Ca- alginate and Sr-alginate were similar, and the addition of bentonite to Ca- and Sr-alginate resulted in an increase of itaconic acid. The addition of 1.67% bentonite and 0.33% starch to Sr-alginate (SABS bead) produced higher level of itaconic acid (11.59 g/1) than other gel beads. A decrease in the size of Celite increased the itaconic acid production, and the smallest size of Celites, R- 634, produced 6.37 g/l of itaconic acid. Among various types of polyurethane foam cubes, HR 08 (2X2X2 cm) produced about 19 g/l of itaconic acid, which was more efficient than other carriers. In a repeated batch culture using immobilized cells on polyurethane foam cubes (HR 08, 2X2X2 cm), the stability of itaconic acid production was maintained up to 4 batches. Also, the possibility of itaconic acid production by continuous culture was shown in a packed-bed reactor.

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HYDROGEN DECREPITATION AND MAGNETIC PROPERTIES OF $Sm_{2}Fe_{17}-TYPE$ ALLOY MODIFIED WITH A SMALL ADDITION OF Nb

  • Kwon, H.W.;Harris, I.R.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.432-436
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    • 1995
  • The hydrogen decrepitation behaviour of the $Sm_{2}Fe_{17} alloy containing 4at%Nb was examined by means of DTA and SEM metallography, and the magnetic properties of the alloy were studied by means of VSM or TMA. It has been found that a simple hydrogenation and degassing treatment for the alloy caused a poor hydrogen decrepitation. The cycle treatment consisting of repeated hydrogenation and degassing, however, caused a severe hydrogen decrepitation with a combination of intergranular and transgranular failure. The disproportionation temperature of the hydrogenated $Sm_{2}Fe_{17}-type alloy was enhanced significantly by small addition of Nb. It has also been found that the Curie temperature of $Sm_{2}Fe_{17} matrix phase in the Nb-containing alloy has been enhanced by the hydrogenation, and this was attributed to the increase in interatomic distance between the neighbouring iron atoms caused by the interstitial occupancy of the hydrogen atom into the $Sm_{2}Fe_{17}-type lattice. The magnetisation of the $Sm_{2}Fe_{17} alloy containing Nbwas found to be lower than that of the Nb-free alloy, and this was explained by the dilution effect due to the presence of the paramagnetic $Sm_{2}Fe_{17} phase.

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Protection of Skin Fibroblasts from Infrared-A-Induced Photo-Damage Using Ginsenoside Rg3(S)-Incorporated Soybean Lecithin Liposomes

  • Won Ho Jung;Jihyeon Song;Gayeon You;Jun Hyuk Lee;Sin Won Lee;Joong-Hoon Ahn;Hyejung Mok
    • Journal of Microbiology and Biotechnology
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    • v.33 no.1
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    • pp.135-141
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    • 2023
  • Protection of skin cells from chronic infrared-A (IRA) irradiation is crucial for anti-photoaging of the skin. In this study, we investigated the protective activity of Rg3(S) and Rg3(S)-incorporated anionic soybean lecithin liposomes (Rg3/Lipo) with a size of approximately 150 nm against IRA-induced photodamage in human fibroblasts. The formulated Rg3/Lipo showed increased solubility in aqueous solution up to a concentration of 200 ㎍/ml, compared to free Rg3(S). In addition, Rg3/Lipo exhibited superior colloidal stability in aqueous solutions and biocompatibility for normal human dermal fibroblasts (NHDFs). After repeated IRA irradiation on NHDFs, elevated levels of cellular and mitochondrial reactive oxygen species (ROS) were greatly reduced by Rg3(S) and Rg3/Lipo. In addition, cells treated with Rg3/Lipo exhibited noticeably reduced apoptotic signals following IRA irradiation compared to untreated cells. Thus, considering aqueous solubility and cellular responses, Rg3/Lipo could serve as a promising infrared protector for healthy aging of skin cells.

Quality Characteristics of Ssukgaen Dduk Made with High-Dietary Fiber Rice 'Goami 2' Focused on Yam (마 첨가가 고아미 2호로 만든 쑥갠떡의 품질 특성에 미치는 영향)

  • Ha, Hyun-Suk;Kim, Hyun-Ah;Lee, Kyung-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.19 no.6
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    • pp.1032-1038
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    • 2009
  • This study describes the production of functional Ssukgaen Dduk though the addition of yam and mugwort to Goami 2, a healthy diet and diabetes. In this study, the rice is soaked for many hours and the particle size distribution of the rice was determined as a function of the water-soaking time. The produce Ssukgaen Dduk was repeated after the addition of varying concentration of yam. Non-glutinous rice was soaked for 4, 8, 12 hours and the Goami 2 rice was soaked for 4, 8, 12, 16, 20 hours and ground to a powder and passed through a 18~30 mesh sieve to determine the particle size distribution of the rice as a function of water-soaking time. Using this approach, optimal soaking time for Dduk was found to be 4 hours for non-glutinous rice(pass rate of 30 mesh: 58.29%) and 12 hours for Goami 2(pass rate of 30 mesh: 87.88%). When Ssukgaen Dduk made with Goami 2 rice powder only and those made with varying amounts of yam(10%, 20%, 30%, and 40%) were subjected to the sensory test, the control group(non-glutinous rice Ssukgaen Dduk) had the highest preference in general(3.73). Out of Ssukgaen Dduk containing yam, the S4 group, which contained 30% yam, had the highest preference(2.87) In addition the S4 group also had the highest extent of soft, and delicacy of texture general preference of S5, 40% the lowest(2.37), S1 only Goami 2 the hardness(112.59), as 91.46 lower (83.85) yam increased, the less hard the texture Ssukgaen Dduk. In conclusion Ssukgaen Dduk though the addition of mugwort and yam to the Goami 2 rice, it would be better to add 30% yam to 70% Goami 2 rice powder mixed with mugwort.

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Influence of Compost Recycling and Magnesium Supplement on Physical and Chemical Traits of Animal Manure Compost

  • Lee, Jin-Eui;Kwag, Jung-Hoon;Ra, Chang-Six
    • Journal of Animal Science and Technology
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    • v.52 no.6
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    • pp.513-519
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    • 2010
  • A series of experiments were performed to study the influence of the following parameters on the physical traits and composition of swine manure compost: (1) addition of magnesium (Mg) at a molar ratio of 1.2 with respect to $PO_4$, and (2) reutilization of compost containing $MgNH_4PO_4{\cdot}6H_2O$ (magnesium ammonium phosphate, MAP). Three independent batch tests were conducted for replication: batch test I-control (C) and Mg added (T), batch test II-C, T and compost recycle ($T_{R1}$), and batch test III-C, T and compost recycle ($T_{R2}$). Magnesium addition and compost reutilization had no adverse effect on the degradation of organic matter. Reuse of the compost, however, had a clear effect on the total nitrogen (TN) and total phosphorus (TP) contents in the final compost. Repeated compost reutilization as a bulking material was resulted in composts rich in N and P. Upon adding the Mg supplement to the composting materials, the ortho-phosphate (OP) to TP ratio decreased due to the MAP crystallization reaction. The decrease in the OP/TP ratio and the increase in the TP content of the compost indicate that water-soluble phosphate is converted into a slow-release phosphate by the formation of crystals during composting. X-ray diffraction analysis of the irregular shaped crystals in the compost indicated that they are MAP crystals and that the crystallization of MAP begins immediately after the addition of the Mg supplement. The Mg addition to composting materials and the reutilization of compost as a bulking material would be a practical means to conserve nutrient content.

Cryoprotective Properties of Exopolysaccharide (P-21653) Produced by the Antarctic Bacterium, Pseudoalteromonas arctica KOPRI 21653

  • Kim, Sung-Jin;Yim, Joung-Han
    • Journal of Microbiology
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    • v.45 no.6
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    • pp.510-514
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    • 2007
  • Twenty-five bacterial strains that secrete mucous materials were isolated from sediment obtained from King George Island, Antarctica. Seven of these strains proved capable of producing cryoprotective exopolysaccharides. The strain KOPRI 21653 was selected for the further study of an anti-ice-nucleating polysaccharide (ANP), which originated from a polar region. KOPRI 21653 was identified as Pseudoalteromonas arctica as the result of 16S rRNA analysis. The exopolysaccharide, P-21653, was purified completely from the KOPRI 21653 cell culture via column chromatography and protease treatment. The principal sugar components of P-21653 were determined to be galactose and glucose, at a ratio of 1:1.5, via GC-MS analysis. The cryoprotective activity of P-21653 was characterized via an E. coli viability test. In the presence of 0.1% (w/v) P-21653, the survival ratio of E. coli cells was as high as 82.6% over three repeated freeze-thaw cycles. The survival ratio decreased drastically to 71.5 and 48.1 %, respectively, in five and seven repeated cycle conditions; however, the survival ratios were greater over three (96.6-92.1%) to seven (100.5-91.6%) freeze-thaw cycles in the presence of 0.5 and 1.0% (w/v) P-21653. In addition, at much lower concentrations (0.1-1.0%), P-21653 resulted in survival ratios (83.1-98.4%) similar to those of two commercially available cryoprotectants ($V_{EG}$ plus X-1000, 92.9% and $V_{M3}$, 95.3%), which were utilized at the recommended concentrations (90%). The biochemical characteristics of exopolysaccharide P-21653 reflect that this compound may be developed as a useful cryoprotectant for use in medical applications and in the food industry.

Comparison of GEE Estimation Methods for Repeated Binary Data with Time-Varying Covariates on Different Missing Mechanisms (시간-종속적 공변량이 포함된 이분형 반복측정자료의 GEE를 이용한 분석에서 결측 체계에 따른 회귀계수 추정방법 비교)

  • Park, Boram;Jung, Inkyung
    • The Korean Journal of Applied Statistics
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    • v.26 no.5
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    • pp.697-712
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    • 2013
  • When analyzing repeated binary data, the generalized estimating equations(GEE) approach produces consistent estimates for regression parameters even if an incorrect working correlation matrix is used. However, time-varying covariates experience larger changes in coefficients than time-invariant covariates across various working correlation structures for finite samples. In addition, the GEE approach may give biased estimates under missing at random(MAR). Weighted estimating equations and multiple imputation methods have been proposed to reduce biases in parameter estimates under MAR. This article studies if the two methods produce robust estimates across various working correlation structures for longitudinal binary data with time-varying covariates under different missing mechanisms. Through simulation, we observe that time-varying covariates have greater differences in parameter estimates across different working correlation structures than time-invariant covariates. The multiple imputation method produces more robust estimates under any working correlation structure and smaller biases compared to the other two methods.

Optimal Surface Aeration Rate for Bioethanol Production from the Hydrolysate of Seaweed Sargassum sagamianum Using Pichia stipitis (Pichia stipitis를 이용한 모자반 가수분해물로부터의 bioethanol 생산 시 최적 surface aeration rate)

  • Lee, Sang-Eun;Kim, Hye-Ji;Choi, Woon-Yong;Kang, Do-Hyung;Lee, Hyeon-Yong;Jung, Kyung-Hwan
    • KSBB Journal
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    • v.26 no.4
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    • pp.311-316
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    • 2011
  • We investigated the optimal surface aeration rate during bioethanol production from the hydrolysate of seaweed Sargassum sagamianum using Pichia stipitis. It was observed that, when the working volume was 880 mL in 2.5-L lab-fermentor, the surface aeration rates of 30 to 100 mL/min were the optimal values for bioethanol production, in which this surface aeration rate corresponded to less than 0.05 (1/min) as the oxygen transfer rate coefficient ($k_La$). In addition, during repeated-batch operation was carried out, we examined whether those surface aeration rates were the optimal for bioethanol production. It was also observed that the surface aeration rates of 30 to 100 mL/min in the working volume of 880 mL were the optimal values in terms of the cumulative bioethanol producrion and bioethanol yield. On the basis of the oxygen transfer rate coefficient it is probable that those surface aeration rates will be applied to the large-scale bioethanol production from the hydrolysate of seaweed Sargassum sagamianum.

Effects of real-time feedback training on weight shifting during golf swinging on golf performance in amateur golfers

  • Hwang, Ji-Hyun;Choi, Ho-Suk;Shin, Won-Seob
    • Physical Therapy Rehabilitation Science
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    • v.6 no.4
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    • pp.189-195
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    • 2017
  • Objective: The purpose of this study was to examine the effects of real-time visual feedback weight shift training during golf swinging on golf performance. Design: Repeated-measures crossover design. Methods: Twenty-sixth amateur golfers were enrolled and randomly divided into two groups: The golf swing training with real-time feedback on weight shift (experimental group) swing training on the Wii balance board (WBB) by viewing the center of pressure (COP) trajectory on the WBB. All participants were assigned to the experimental group and the control group. The general golf swing training group (control group) performed on the ground. The golf performance was measured using a high-speed 3-dimensional camera sensor which analyses the shot distance, ball velocity, vertical launch angle, horizontal launch angle, back spin velocity and side spin velocity. The COP trajectory was assessed during 10 practice sessions and the mean was used. The golf performance measurement was repeated three times and its mean value was used. The assessment and training were performed at 24-hour intervals. Results: After training sessions, the change in shot distance, ball velocity, and horizontal launch angle pre- and post-training were significantly different when using the driver and iron clubs in the experimental group (p<0.05). The interaction time${\times}$group and time${\times}$club were not significant for all variables. Conclusions: In this study, real-time feedback training using real-time feedback on weight shifting improves golf shot distance and accuracy, which will be effective in increasing golf performance. In addition, it can be used as an index for golf player ability.

A Study on the Property of Hair Dyed with Fermented Indigo (천연염료 발효(天然染料 醱酵) 쪽으로 염색(染色)한 모발(毛髮)의 특성 연구(特性 硏究))

  • Kim, Kyung-Sun;Lee, In-Sook;Jeon, Dong-Won;Ha, Byung-Jo
    • Journal of Fashion Business
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    • v.10 no.1
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    • pp.120-131
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    • 2006
  • Recently, it has been reported that chemical hair coloring can cause allergic reactions, the toxicity issue of chemical hair color was issued. Therefore, there is an increasing interest in the hair coloration technique using non-toxic and bio-compatible hair color gotten from natural resource. In this study, the possibility using fermented Indigo as natural hair coloring agent was investigated. Bleached hair samples were dyed using Indigo, and the effect of dyeing frequency, the physical change after dyeing, color, surface and cross-section characteristics, and tensile property were also studied. In addition, the protection property of cationic detergent finishing on damaged hair samples were also studied. The following conclusions are made; 1. While bleached hair samples with low value showed the negligible effect of repeated dyeing, bleached hair samples with high value showed the good effect of repeated dyeing. 2. Hair sample dyed with Indigo showed a high light-fastness, however, tensile strength and elongation showed very low values (high damage on hair sample). 3. Cationic detergent finishing did not affect on the colorfastness because of decoloration after dyeing, however, it increased the smoothness of hair sample, and therefore, can use as protectant of damaged hair. 4. Hair scale was damaged after dyeing. It seemed that the alkali, potassium carbonate, increased pH of dyeing bath to 11, as a result, the hair was swollen, weaken, and dissolved on the prolonged dyeing time. Dyed hair sample became stiff and fine. 5. The color difference was 4.62 (a high fastness value) in the test of sunlight exposure, shampoo, cationic detergent finishing, and acid perspiration fastness.