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  • Title/Summary/Keyword: polymerization degree

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Preparation Of levan Oligosaccharides by Acid Hydrolysis and It Application in Growth of lactic Acid-producing Bacteria (산가수 분해법에 의한 레반 올리고당의 제조 및 유산군 생육촉진 효과 연구)

  • 강태호;정성제;강순아;강기효;장은경;김승환;김철호;이상기;전억한
    • KSBB Journal
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    • v.17 no.2
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    • pp.137-141
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    • 2002
  • Levan oligosaccoharides and low molecular weight levin were produced from levin by acid hydrolysis and following column chromatography. Levan hydrolysis was progressed proportionally as increased incubation time. In terms of levan hydrolysis reaction, no differences were found from the sources of levan. Optimum hydrolysis conditions for the formation of levan oligosaccharides were, 0.38 M H2S04; and incubation at 95\^C for 4 min. The purified products were determined as the mixture of oligosaccharides (degree of polymerization (DP) of 3-6), Two of lactic acid-producing bacteria, Lactobacillus plantarum KCTC 3104 and Pediococcus pentosaceus KCTC 3507, were studied in vitro for their ability to metabolize levin oligosaccharides. Apparently, the growth of both cells were increased by levin oligosaccharide diet, compared with those of levan diets, suggesting that levan oligosaccharides may be beneficial in selectively growth of lactic acid-producing bacteria.

Fermentation of purple Jerusalem artichoke extract to improve the α-glucosidase inhibitory effect in vitro and ameliorate blood glucose in db/db mice

  • Wang, Zhiqiang;Hwang, Seung Hwan;Lee, Sun Youb;Lim, Soon Sung
    • Nutrition Research and Practice
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    • v.10 no.3
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    • pp.282-287
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    • 2016
  • BACKGROUND/OBJECTIVES: Jerusalem artichoke has inhibitory activity against α-glucosidase and decreases fasting serum glucose levels, which may be related to its fructan content. The biological activity of fructan can be influenced by the degree of polymerization. Thus, in this study, the inhibitory effects of original and fermented purple Jerusalem artichoke (PJA) on α-glucosidase were compared in vitro. Additionally, the anti-diabetes effect of Lactobacillus plantarum-fermented PJA (LJA) was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db). MATERIALS/METHODS: The water extract of PJA was fermented by L. plantarum, and two strains of Bacillus subtilis to compare their anti-α-glucosidase activities in vitro by α-glucosidase assays. The anti-diabetes effect of LJA was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db) for seven weeks. During the experiment, food intake, body weight, and fasting blood glucose were measured every week. At the end of the treatment period, several diabetic parameters and the intestinal α-glucosidase activity were measured. RESULTS: The LJA showed the highest α-glucosidase inhibitory activity in vitro. In the in vivo study, it resulted in a significantly lower blood glucose concentration than the control. Serum insulin and HDL cholesterol levels were significantly higher and the concentrations of triglycerides, non-esterified fatty acids, and total cholesterol were significant lower in mice treated with LJA after seven weeks. In addition, the intestinal α-glucosidase activity was partially inhibited. CONCLUSIONS: These results suggested that LJA regulates blood glucose and has potential use as a dietary supplement.

Effects of CH2F2 and H2 flow rates on process window for infinite etch selectivity of silicon nitride to PVD a-C in dual-frequency capacitively coupled plasmas

  • Kim, Jin-Seong;Gwon, Bong-Su;Park, Yeong-Rok;An, Jeong-Ho;Mun, Hak-Gi;Jeong, Chang-Ryong;Heo, Uk;Park, Ji-Su;Lee, Nae-Eung
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.250-251
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    • 2009
  • For the fabrication of a multilevel resist (MLR) based on a very thin amorphous carbon (a-C) layer an Si3N4 hard-mask layer, the selective etching of the Si3N4 layer using physical-vapor-deposited (PVD) a-C mask was investigated in a dual-frequency superimposed capacitively coupled plasma etcher by varying the following process parameters in CH2F2/H2/Ar plasmas : HF/LF powr ratio (PHF/PLF), and CH2F2 and H2 flow rates. It was found that infinitely high etch selectivities of the Si3N4 layers to the PVD a-C on both the blanket and patterned wafers could be obtained for certain gas flow conditions. The H2 and CH2F2 flow ratio was found to play a critical role in determining the process window for infinite Si3N4/PVDa-C etch selectivity, due to the change in the degree of polymerization. Etching of ArF PR/BARC/SiOx/PVDa-C/Si3N4 MLR structure supported the possibility of using a very thin PVD a-C layer as an etch-mask layer for the Si3N4 layer.

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Changes in Amylopectin Structure and Pasting Properties of Starch as Affected by Different Transplanting Dates in Rice

  • Kim, Sang-Kuk;Shin, Jong-Hee;Ahn, Deuk-Jong;Kim, Se-Jong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.61 no.4
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    • pp.235-241
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    • 2016
  • Three different transplanting dates for two rice cultivars grown in Daegu, Republic of Korea, were examined to identify the changes in growth, rice quality, and characteristics of amylopectin. An early transplanting date caused a reduction in the number of panicles in both rice cultivars compared to that in the optimal and late transplanting dates. The 1000-grain weight in the two rice cultivars was significantly increased in the late transplanting date. The rice cultivar tolerant to high temperatures, Donganbyeo, exhibited the lowest milky grain rate in the late transplanting date. The highest rate of head grain was observed in the late transplanting date in both rice cultivars. Regarding the pattern of pasting properties, peak viscosity increased with delayed transplanting dates. With respect to changes in the amylopectin branch-chain length distribution, the amylopectin structure of the translucent Dongan rice cultivar transplanted on April 25 was characterized by a significant increase in A chains with DP > 12, and a decrease in long chains DP37 compared to that transplanted on June 25. In contrast, the amylopectin structure of the chalky Dongan rice cultivar transplanted on April 25 exhibited further decrease in 13 < DP < 19 than that transplanted on June 25. In the Ungwang rice cultivar, the amylopectin structure of the translucent Ungwang rice cultivar transplanted on April 25 and June 25 was characterized by a significant decrease in the lengths of total amylopectin chains. Furthermore, the amylopectin structure of the chalky Ungwangbyeo rice cultivar transplanted on April 25 was characterized by a significant increase in 7 < DP < 30, while a significant decrease was observed in that transplanted on June 25. These results indicate that the amylopectin structure is altered by different transplanting dates depending on the characteristics of the rice cultivar.

Rheological Measurement of Fiber Spinnability of PVA Solution Dopes in DMSO

  • Chae, Dong-Wook
    • Textile Coloration and Finishing
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    • v.22 no.3
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    • pp.187-193
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    • 2010
  • The effects of molecular weight (MW) and concentration on the rheological properties of poly(vinyl alcohol) (PVA) solutions in dimethyl sulfoxide (DMSO) were investigated at 30C. Ubbelohde viscometer and rotational rheometer were employed for dilute and concentrated regime, respectively. In the dilute regime, the Mark-Houwink exponent (α) of the solutions determined from three different MWs proved 0.73. The critical concentration (C*), in which the entanglement and overlap of polymer molecules began to take place, decreased with increasing the MW of PVA. Huggins constant (KH) values ranged from 0.33 to 0.45 over the MW examined. In the log-log plot of ηsp versus [η]C, the PVA with higher degree of polymerization (DP) gave a greater slope exhibiting the inflection point in the vicinity of C*. In the dynamic viscosity (η) curve, the PVA solutions of DP 1700 presented Newtonian fluid behavior over most of the frequency range examined. However, the lower Newtonian flow region reduced with increasing the DP. As the PVA concentration increased, η was increased and the onset shear rate for pseudoplasticity was decreased. In the Cole-Cole plot, PVA solutions showed almost a single master curve in a slope of ca. 1.65 regardless of the DP. However, the increase of the concentration from 8 to 12 wt% for PVA solutions of DP 5000 decreased the slope from 1.73 to 1.57. In the tan δ curve, the onset frequency for sol-gel transition was shifted from 154 to 92 rad/s with increasing the DP from 3300 to 5000 and from 192 to 46 rad/s with increasing the concentration from 8 to 12 wt%. In addition, longer relaxation time (λ) was observed with increasing the DP and concentration.

Comparison of brassiere sales patterns in Korea and China

  • Cha, Su-Joung;Sohn, Hee-Soon
    • Journal of Fashion Business
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    • v.12 no.6
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    • pp.107-123
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    • 2008
  • The purpose of this research is to compare and analyze the brassiere patterns sold in Shanghai and Korea and to present basic materials needed in developing the brassiere patterns in Chinese adult women market. The study subject which is to find the difference in brassiere patterns of Korea and China has been selected of 3 Korean brands and 4 Chinese brands. 1. For the brassiere patterns sold in Korea, it were using the same size for the width of Hook&Eye, space between the shoulder lace on the back, slope of wing and the location of the Keeper was similar. 2. For the cup supporting base, Chinese brassiere covers the lower part of the breast and as it is not comfortable and has a phenomenon of loosening up, there were severe puckering. For issues in the wearing experiment, amendments in patterns with the cup part was required. 3. Chinese brassieres were big differences in wing angles and for Aimer, it had the steepest trend in wings and thus the wings headed down and for Gujin, as the angle of the wing was smaller than 90, it was heading upward. 4. Upon comparing the patterns of the Korean and Chinese brassiere, although most of the sizes excluding the wing angle had similar sizes, there was big differences in the wing angle. The reason why the brassiere patterns sold in China had bigger wing angle was due to the fact that more Chinese women had sway back body type than the Korean women and should reflect such difference in body size into making the brassiere patterns for each women.

Antioxidative Effect of Commercial Lecithin on the Oxidative Stability of Fish Oil (어유의 산화안정성에 미치는 레시틴의 산화방지 작용)

  • Ahn, Tae-Hoe;Kim, Jin-Ho;Kim, Hyun-Suk;Park, Ki-Moon;Choi, Chun-Un
    • Korean Journal of Food Science and Technology
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    • v.23 no.5
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    • pp.578-581
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    • 1991
  • The antioxidative effects of three kinds of commercial lecithin in fish oil(EPA 25%, DHA 10%) were investigated through active oxygen method (AOM, hrs. at 97.8C), Oven test, polymer test by gel chromatography and coloring test. Although there were difference of antioxidative effect among commercial lecithins, antioxidative effects of the lecithins added to the fish oil increased with increasing the concentration of lecithin. Lecithin III(acetone insoluble content 65%) had the greatest antioxidative effect and the addition of 1%, 5 and 10% enhanced the oxidative stability to 310%, 620% and 840%, respectively. The results also showed that the polymerization in presence of 10% lecithin III did not occur up to 10 hours at the AOM condition, and the degree of color(Gardner number) increased as storage time went by and was accerated at high temperature.

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Membrane Performance and Chemical Instability of 1,3,5-Benzenetricarbonyl Trichloride (1,3,5-Benzenetricarbonyl Trichloride의 화학적 불안정성과 분리막 성능)

  • Park, Chul Ho;Kim, Chan-soo;Sim, Joonmok;Park, Hyun-Seol;Joe, Yun-Haeng
    • Membrane Journal
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    • v.30 no.3
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    • pp.200-204
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    • 2020
  • 1,3,5-benzenetricarbonyl trichloride is a chemical substance in which three acyl chlorides are located at 1,3,5 position in the benzene ring, and is an important chemical for the area where the good physical and chemical properties are required through high degree of crosslinking. In particular, it is possible to form a three-dimensional structure having a certain pore size, it is used in various separation and purification fields. However, the high reactivity of acyl chloride has the advantage of a fast reaction rate, which means that it is difficult to control chemically to have a certain performance in other aspects. Therefore, in this study, we observed how the chemical change of 1,3,5-benzenetricarbonyl trichloride affected the membrane performance.

Characteristics of the symbionts Pseudomonas sp. J2W strain and Xanthomonas sp. J2Y strain which utilize polyvinyl alcohol (Polyvinyl alcohol 이용 공생균 Pseudomonas sp. J2W와 Xanthomonas sp. J2Y의 특성)

  • Jo, Youn-Lae
    • Applied Biological Chemistry
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    • v.35 no.1
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    • pp.30-35
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    • 1992
  • Two strains J2W and J2Y which were isolated from soil can utilize polyvinyl alcohol(PVA) as a sole carbon source. PVA was utilized symbiotically by the mixed culture of these two strains which could not utilize PVA in each respective pure culture. Effect of degree of PVA polymerization on the its utilization was examed, and there was remarkable difference among three kind of PVA(PVA 500, 1500 and 2000). The reconstruction of there two strains was carried out with other symbionts Pseudomonas sp. PW and Pseudomonas sp. G5Y which were able to utilize PVA. PVA utilization occured in each remixed culture of J2Y strain with Pseudomonas sp. PW J2W strain with Pseudomonas sp. G5Y, respectively. Identification of bacteria was based on morphological and biological chatacteristics, J2W and J2Y strain were similar to a strain of Pseudomonas pseudimallei and Xanthomonas campestris, respectively.

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Physicochemical Properties of Millet Starch Varieties (Millet 품종별 전분의 이화학적 성질)

  • Chung, Koo-Min
    • Korean Journal of Food Science and Technology
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    • v.42 no.1
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    • pp.115-118
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    • 2010
  • The physicochemical properties such as blue value, iodine affinity, degree of polymerization (DP), α-amylase digestibility, particle size, RVA pasting, and gel hardness of 4 different millet starches (foxtail, waxy foxtail, proso, and waxy proso) were investigated. The iodine affinity value of the four samples were 4.22, 0.49, 1.07, and 0.21%, and the DP values were 1830, 3880, 4660, and 4130, respectively. The levels of α-amylase digestibility of the raw starches were 20.1, 30.7, 18.2 and 35.6%, respectively. The mean size of the proso millet starch was the smallest, 8.25μm, and the size distribution of the particles was the narrowest among all the samples. Foxtail starch showed the largest peak viscosity and setback viscosity in RVA pasting.