• Title/Summary/Keyword: N,N-Dimethylformamide

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Separation of Antioxidants and Glucose from Grape Skin Extract Using Polyethylene Glycol and Sodium Citrate (폴리에틸렌글리콜과 구연산 나트륨을 이용하여 포도껍질 추출물에서 항산화물질과 포도당 분리)

  • Eun Min Shin;Yeong Eun Joo;Su Min Jung;Jaechan Suh;Chang-Joon Kim
    • Clean Technology
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    • v.29 no.2
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    • pp.109-117
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    • 2023
  • The purpose of this study is to develop a method for separating antioxidants and sugars from grape skin extract. The extract was first mixed with a variety of organic solvents to investigate whether the separation was feasible. When employing acetone, ethanol, dimethylsulfoxide, or dimethylformamide, the organic solvent-extract combination formed a single phase. However, when benzene, ethyl acetate, or n-hexane was added to the extract, the mixture separated into an organic and an aqueous phase and the pigments remained in the aqueous phase. On the other hand, when polyethylene glycol-2,000 (PEG-2000) and sodium citrate were added to the extract, the mixture was separated into three layers, with the majority of the flavonoids migrating to the top layer and 53% of the extract's glucose migrating to the bottom layer. The top layer had significant antioxidant activity, whereas the bottom layer showed no antioxidant activity. The glucose recovery in the bottom layer increased as the molecular weight of PEG increased and the highest recovery (67%) was observed when PEG-8,000 was added. The highest flavonoid separation was observed with PEG-2,000, followed by PEG-8,000 and PEG-400. The flavonoid separation when PEG-2,000 was added resulted in a flavonoid recovery of 48% and 0.2% from the top and bottom layers, respectively. Examining the effect of the separated solution using the agar disc diffusion method on yeast cell growth confirmed that the addition of the extract, the top, and the bottom layer did not inhibit cell growth.

Effect of N-Methylacetamide Concentration on the Fertility and Hatchability of Cryopreserved Ogye Rooster Semen (N-Methylacetamide 동결 보호제의 농도가 오계 동결 정액의 수정 및 부화율에 미치는 영향)

  • Kim, Sung Woo;Choi, Jin Seok;Ko, Yeoung-Gyu;Do, Yoon-Jung;Byun, Mijeong;Park, Soo-Bong;Seong, Hwan-Hoo;Kim, Chong-Dae
    • Korean Journal of Poultry Science
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    • v.41 no.1
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    • pp.21-27
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    • 2014
  • To preserve chicken genetic materials like cryopreserved spermatozoa, various kinds of freezing agents like glycerol, dimethylsuloxide, dimethylformamide or dimethylacetamide have been used for rooster semen preparation. Recently, the usage of N-methylacetamide (MA) for Ogye rooster semen preservation resulted in hatched chicken successfully. In this study, we investigated the effects of 7, 9 and 11% of MA on the viability, fertility and hatchability of frozen-thawed rooster semen using artificial insemination. The results of viability, fertility and hatchability in frozen semen with 7%, 9% or 11% MA were $35.16{\pm}6.12%$, $67.83{\pm}15.3%$ and $66.2{\pm}16.3%$ of motile sperm rate, 21.5%, 34.7% and 25% of fertility rate, and 100%, 89.5% and 87.5% of hatchability rate. The results of control group with frozen semen were 96.0% of fertility rate and 92.2% of hatchability rate. With these results, the concentration range of MA as a freezing agent of rooster semen could be 7~9% of media. The higher concentration of 9 % MA could decrease the fertility rate of thawed semen not the rate of hatchability rate. So the use of MA without affecting fertility rate would be a key point of freezing method of rooster semen for poultry genetic resource preservation.

Kinetics and Mechanism of the Oxidation of Alcohols by C9H7NHCrO3Cl (C9H7NHCrO3Cl에 의한 알코올류의 산화반응에서 속도론과 메카니즘)

  • Park, Young-Cho;Kim, Young-Sik;Kim, Soo-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.378-384
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    • 2018
  • $C_9H_7NHCrO_3Cl$ was synthesized by reacting $C_9H_7NH$ with chromium (VI) trioxide. The structure of the product was characterized by FT-IR (Fourier transform infrared) spectroscopy and elemental analysis. The oxidation of benzyl alcohol by $C_9H_7NHCrO_3Cl$ in various solvents showed that the reactivity increased with increasing dielectric constant(${\varepsilon}$) in the following order: DMF (N,N'-dimethylformamide) > acetone > chloroform > cyclohexane. The oxidation of alcohols was examined by $C_9H_7NHCrO_3Cl$ in DMF. As a result, $C_9H_7NHCrO_3Cl$ was found to be an efficient oxidizing agent that converts benzyl alcohol, allyl alcohol, primary alcohols, and secondary alcohols to the corresponding aldehydes or ketones (75%-95%). The selective oxidation of alcohols was also examined by $C_9H_7NHCrO_3Cl$ in DMF. $C_9H_7NHCrO_3Cl$ was the selective oxidizing agent of benzyl, allyl and primary alcohol in the presence of secondary ones. In the presence of DMF with an acidic catalyst, such as $H_2SO_4$, $C_9H_7NHCrO_3Cl$ oxidized benzyl alcohol (H) and its derivatives ($p-OCH_3$, $m-CH_3$, $m-OCH_3$, m-Cl, and $m-NO_2$). Electron donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. The Hammett reaction constant (${\rho}$) was -0.69 (308K). The observed experimental data were used to rationalize hydride ion transfer in the rate-determining step.

Effects of Kinds of Cryoprotectants on the Characteristics of Frozen Fowl Semen (닭 정액 동결 시 동결 보호제가 정액 성상에 미치는 영향)

  • Choi, Jin Seok;Shin, Dan-Bi;Ko, Yeoung-Gyu;Do, Yoon-Jung;Byun, Mijeong;Park, Soo-Bong;Seong, Hwan-Hoo;Kim, Hyun;Kong, Il-Keun;Kim, Sung Woo
    • Korean Journal of Poultry Science
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    • v.40 no.3
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    • pp.171-178
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    • 2013
  • The purpose of this study was to evaluate the sperm viability, normal acrosome and mitochondrial activity in the frozen-thawed fowl semen by different cryoprotectants. The experiment was carried out on 10 sexually adult roosters of Ogye. The semen was collected twice a week and pooled semen was diluted 1:1 EK extender containing no cryoprotectant at $5^{\circ}C$. After equilibration for 30 minutes, diluted chicken semen was diluted 1:1 extender containing either 7% dimethylacetamide (DMA), 7% dimethylformamide (DMF) or 7.5% methylacetamide (MA) at final concentration and was put in 0.5 mL plastic straws and frozen for 30 minutes by exposure to liquid nitrogen vapor 4 cm above the surface of liquid nitrogen, followed by plunging into liquid nitrogen. Frozen semen was thawed in water bath at $5^{\circ}C$ for 2 minutes. For cytometric analysis, the frozen-thawed semen was diluted with EK extender to a final concentration of 90 million spermatozoa per mL. Sperm membrane integrity was evaluated as SYBR-14 and propidium iodide (PI). Acrosome integrity was assessed with fluorescein isothiocyanate-labeled PSA and PI. The percentage of mitochondrial function was estimated by using Rhodamine123 (R123) and PI. In conclusion, freezing rooster semen by using 7% DMF as cryoprotectant was significantly highest in rates of survival and mitochondrial function while its rate of damage of acrosome was significantly lowest. As a result, DMF is the cryoprotectant that has the lowest influences on sperm membranes and acrosome integrity. Therefore it could be used for freezing method of animal genetic conservation method for poultry diversity.

Effect of Nonsolvent Additive in Casting Solutions on Polysulfone Membrane Preparation (Polysilfone 막의 제조에 있어 제막용액에 첨가된 비용매의 영향)

  • 한명진
    • Membrane Journal
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    • v.6 no.3
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    • pp.157-165
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    • 1996
  • Polysulfone(PS) membranes were prepared from homogeneous PS solutions by the phase inversion technique. When propionic acid(PA) was added into a casting solution of n-methylpyrrolidone(NMP) and PS, precipitation rate of the solution film was accelerated. This kind of acceleration was consistent, even though a precipitating nonsolvent was changed from water to isopropanol. These phenomena were caused by decrease of nonsolvent tolerance in the casting solution due to addition of PA. PS powder was prepared by precipitation of a 3wt% solution in dimethylformamide(DMF) using ethanol as nonsolvent. Gas adsorption analysis of the powder showed that the capillary condensation sites were found in the powder structure. Membranes prepared from PS solution(15wt%) in NMP had the following characteristics of gas adsorption and water permeation. In gas adsorption analysis, the membrane precipitated using isopropanol showed low uptake of nitrogen gas and the capillary condensation sites were not found. On the contrary, a significant amount of the capillary condensation sites was found in the membrane coagulated by water, which was related to increase of nitrogen uptake. tn the membrane prepared froin the solution including PA, an increase of the Henry's law sites and the Langmuir sites was not found clearly. However, the capillary condensation sites were significantly increased, and the water transport also increased.

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Radiosynthesis of $[^{11}C]6-OH-BTA-1$ in Different Media and Confirmation of Reaction By-products. ($[^{11}C]6-OH-BTA-1$ 조제 시 생성되는 부산물 규명과 반응용매에 따른 표지 효율 비교)

  • Lee, Hak-Jeong;Jeong, Jae-Min;Lee, Yun-Sang;Kim, Hyung-Woo;Lee, Eun-Kyoung;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.3
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    • pp.241-246
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    • 2007
  • Purpose: $[^{11}C]6-OH-BTA-1$ ([N-methyl-$^{11}C$]2-(4'-methylaminophenyl)-6-hydroxybenzothiazole, 1), a -amyloid imaging agent for the diagnosis of Alzheimer's disease in PET, can be labeled with higher yield by a simple loop method. During the synthesis of $[^{11}C]1$, we found the formation of by-products in various solvents, e.g., methylethylketone (MEK), cyclohexanone (CHO), diethylketone (DEK), and dimethylformamide (DMF). Materials and Methods: In Automated radiosynthesis module, 1 mg of 4-aminophenyl-6-hydroxybenzothiazole (4) in 100 l of each solvent was reacted with $[^{11}C]methyl$ triflate in HPLC loop at room temperature (RT). The reaction mixture was separated by semi-preparative HPLC. Aliquots eluted at 14.4, 16.3 and 17.6 min were collected and analyzed by analytical HPLC and LC/MS spectrometer. Results: The labeling efficiencies of $[^{11}C]1$ were $86.0{\pm}5.5%$, $59.7{\pm}2.4%$, $29.9{\pm}1.8%$, and $7.6{\pm}0.5%$ in MEK, CHO, DEK and DMF, respectively. The LC/MS spectra of three products eluted at 14.4, 16.3 and 17.6 mins showed m/z peaks at 257.3 (M+1), 257.3 (M+1) and 271.3 (M+1), respectively, indicating their structures as 1, 2-(4'-aminophenyl)-6-methoxybenzothiazole (2) and by-product (3), respectively. Ratios of labeling efficiencies for the three products $([^{11}C]1:[^{11}C]2:[^{11}C]3)$ were $86.0{\pm}5.5%:5.0{\pm}3.4%:1.5{\pm}1.3%$ in MEK, $59.7{\pm}2.4%:4.7{\pm}3.2%:1.3{\pm}0.5%$ in CHO, $9.9{\pm}1.8%:2.0{\pm}0.7%:0.3{\pm}0.1%$ in DEK and $7.6{\pm}0.5%:0.0%:0.0%$ in DMF, respectively. Conclusion: The labeling efficiency of $[^{11}C]1$ was the highest when MEK was used as a reaction solvent. As results of mass spectrometry, 1 and 2 were conformed. 3 was presumed.