• Title/Summary/Keyword: Buffer solubility

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Adsorption Characteristic of L-tryptophan of Affinity Membrane (친화막의 L-tryptophan 흡착특성)

  • Byun, Hong-Sik;Hong, Byung-Pyo
    • Membrane Journal
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    • v.18 no.3
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    • pp.214-218
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    • 2008
  • Protain affinity membranes based on PES-BSA was preapared by the electrospinning method. The process problem caused by the electrospining was solved by using HFB having high solubility and boiling point. It was expecting that the mass production of protein affinity membrane would be possible with broad range of optimized temperature and humidity. BSA in the PES nanofiber was confirmed by the color change from colorless to violet during the biuret test. The buffer solution with DMSO showed that the amount of elution was 5 times higher than the one when the buffer solution without DMSO was used. This is due to the restriction effect of DMSO on the dissociation of L-tryptophan from BSA during the washing step.

Pharmaceutical Study on Pranoprofen Argininate and Pranoprofen Lysinate (Pranoprofen Argininate 및 Pranoprofen Lysinate의 약제학적 연구)

  • Jee, Ung-Kil
    • Journal of Pharmaceutical Investigation
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    • v.17 no.4
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    • pp.197-204
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    • 1987
  • Novel pranoprofen algininate and lysinate salts were manufactured and their salt formation was confirmed by melting point, infrared spectroscopy, nuclear magnetic resornance spectroscopy, differential scanning calorimetry and powder X-ray diffractometry. The physical properties of pranoprofen lysinate and argininate salts were compared with those of pranoprofen through in vitro and in vivo tests. Solubility, $pK_a$ and lipid-water partition coefficient were measured through in vitro experiments, while antiinflammatory efficacy, analgesic effect, acute toxicity and in situ absorption were tested through in vivo experiments. The results obtained were as follows: 1) The solubilities of pranoprofen argininate and lysinate salts were increased markedly in pH 6.8 and pH 7.5 phosphate buffer solutions, comparing with that of pranoprofen itself. 2) $pK_a$ values of pranoprofen, pranoprofen argininate and lysinate salts were 6.34, 7.99 and 7.56 in carbon tetrachloride, and 5.86, 6.69 and 7.92 in chloroform, respectively by liquid-liquid partition method. 3) The lipid-water partition coefficients of pranoprofen argininate and lysinate salts were increased more than that of pranoprofen in carbon tetrachloride, chloroform, or benzene-pH 6.8 buffer system, but were nearly identical using pH 1.2 buffer as water phase. 4) Antiinflammatory effects of pranoprofen argininate and lysinate salts were remarkably increased and analgesic effects of the salts were as same as that of pranoprofen. 5) Pranoprofen argininate and lysinate salts were safer than pranoprofen itself in acute toxicity, and the in situ absorption rates of pranoprofen, pranoprofen argininate and lysinate salts were 0.392, 0.960 and $0.762\;hr^{-1}$, respectively according to the rat intestine recirculation experiment.

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Predicting In Sacco Rumen Degradation Kinetics of Raw and Dry Roasted Faba Beans (Vicia faba) and Lupin Seeds (Lupinus albus) by Laboratory Techniques

  • Yu, P.;Egan, A.R.;Leury, B.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.10
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    • pp.1377-1387
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    • 2000
  • Two laboratory techniques: (1) an in vitro method with two procedures for measuring protein degradabilities and (2) an in vitro method with three procedures for measuring protein solubility, were investigated to determine which laboratory techniques could most accurately predict the quantity of rumen protein degradation kinetics of legume seeds after dry roasting under various conditions, in terms of (1) rumen protein disappearance ($D_j$, where j=0, 2, 4, 8, 12, 24 and 48 h incubation), (2) rumen protein effective degradability (EDCP), (3) the parameters describing rumen degradation characteristics (the soluble fraction: S, the potentially degradable fraction: D, undegradable fraction: U, lag time: T0 and the degradation rate: Kd) and (4) rumen bypass protein (BCP), which were determined by the method accepted internationally at present, in sacco nylon bag technique using the standardized Dutch method. Feeds evaluated were the raw and dry roasted whole faba (Vicia faba) beans (WFB) and whole lupin (Lupinus albus) seeds (WLS), each was dry roasted under various conditions (at 110, 130 or $150^{\circ}C$ for 15, 30 or 45 min). In vitro protein degradability ($D_1$_Auf and $D_{24}$_Auf) were determined using the modified Aufr re method by enzymatic hydrolysis for 1 h and 24 h using a protease extracted from Streptomyces griseus in a borate-phosphate buffer. In vitro protein solubility ($bf_1$_S, $bf_2$_S, $bf_3$_S) was measured in a borate-phosphate buffer with three different procedures. Results from laboratory techniques (in vitro) were correlated and linearly regressed with in sacco results. Of the three procedures of in vitro protein solubility evaluated, none of them could predict in sacco results with good precision. The highest Pearson correlation coefficient ($R^2$) was less than 0.50. Of two procedures of in vitro protein degradability studied, the $D_1$_Auf values were closely correlated with in sacco parameters: Kd, EDCP and %BCP with high R' values: 0.82, 0.85 and 0.85, respectively, and closely correlated with in sacco $D_j$ at 2, 4, 8 and 12 h rumen incubation with high $R^2$ values: 0.83, 0.91, 0.93 and 0.83, respectively. The $D_{24}$_Auf values could not predict in sacco results. The highest $R^2$ value was less then 0.40. These results indicated that in vitro protein solubility measured in borate-phosphate failed to identify differences in the rate and extent of protein degradation of legume seeds after dry roasting under various conditions and thus should not be used to predict rumen degradation, particularly for heat processed feedstuffs. But in vitro protein degradability using the modified Aufr re method by enzymatic hydrolysis for 1 h or possibly an intermediate time (>1 h and <24 h) is a promising laboratory procedure to detect effectiveness of dry roasting legume seeds on rumen protein degradation characteristics and could be used as a simple laboratory method to predict the rate and extent of protein degradation in the rumen in sacco with high accuracy. The equations to predict EDCP, Kd and BCP of dry roasted legume seeds (WLS and WFB) under various conditions are as follow: For both: EDCP (%)=-1.37+1.06*$D_1$_Auf ($R^2=0.85$, p<0.01). For both: Kd (%/h)=-21.81+0.49*$D_1$_Auf ($R^2=0.82$, p<0.01). For both: %BCP=103.37-1.07*$D_1$_Auf ($R^2=0.85$, p<0.01).

Responses of Chloramphenicol Immunosensor to Analyte Types

  • PARK , IN-SEON;KIM, DONG-KYUNG;KIM, NAM-SOO
    • Journal of Microbiology and Biotechnology
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    • v.14 no.6
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    • pp.1157-1162
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    • 2004
  • A well-holder type piezoelectric chloramphenicol (CAP) immunosensor which was prepared by binding an anti­CAP antibody to the chemisorbed monolayers of various thiol or sulfide compounds over the gold electrode surface of quartz crystals through a carboxyl-amine coupling procedure, using the activation with l-ethyl- 3-(3-dimethylarninopropyl)carbodiimide­HCl and N-hydroxysulfosuccinimide, was determined for its responses to CAP, CAP succinate, and water-soluble CAP. The reaction phase used in the well holder was 0.01 M phosphate buffer (pH 7.4), and the solvent for analyte dissolution varied according to the solubility of the individual analyte. The analyte detection which was indicated by a steady-state frequency shift was finished within 10 min, except for CAP dissolved in methanol. The responses of CAP succinate and water-soluble CAP in the reaction phase were very stable, while a minute fluctuation was found with CAP.

The Intestinal Absorption of Lysino-Methylene-Ampicillin in Rat (Lysino-Methylene-Ampicillin의 Rat 소장흡수(小腸吸收)에 관한 연구(硏究))

  • Chin, Kum-Sup;Kim, Jong-Kap;Kim, Jae-Baek
    • Journal of Pharmaceutical Investigation
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    • v.9 no.1
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    • pp.15-19
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    • 1979
  • The absorption rate of lysino-methylene-ampicillin from the rat small intestine, compared with ampicillin, was determined in vitro and in situ to establish the biopharmaceutical properties of lysino-methylene-ampicillin which is one of the new penicillinase-resistance antibiotics. The half of administered dose was absorbed rapidly within thirty minutes. The water-oil distribution coefficient of lysino-methylene-ampicillin was 0.03 in chloroform versus buffer system with $Na_{2}HPO_{4}-citric$ acid of pH5.2 at $37^{\circ}C$, and its dissolution rate reached the plateau in an hour and then represented 0.6 percent of equilibrium solubility

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Preparation of Microparticulate Itraconazole/Hydroxypropyl-$\beta$-cyclodextrin Inclusion Complexes Using a Supercritical Anti-Solvent [SAS] Process (초임계 역용매 공정을 이용한 Itraconazole/Hydroxypropyl-$\beta$-cyclodextrin 포접복합체 미세입자 제조)

  • 이상윤;김정규;김우식;유종훈;임교빈
    • KSBB Journal
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    • v.19 no.4
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    • pp.321-326
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    • 2004
  • Microparticles of an inclusion complex between itraconazole and 2-hydroxypropyl-${\beta}$-cyclodextrin (HP-${\beta}$-CD) were prepared using an environmentally-benign supercritical anti-solvent (SAS) process. In order to evaluate the degree of complexation, the thermal behavior of solid micro particulate complexes was investigated using differential scanning calorimetry. The experimental results obatined for the solubility and dissolution rate of the microparticulate inclusion complexes in a buffer solution of pH 1.2 showed that the complexation of itraconazole with HP-${\beta}$-CD results in a significant increase in the solubility and dissolution rate of itraconazole. For the microparticulate itraconazole/Hp-${\beta}$-CD inclusion complexes prepared by the SAS process, about 80% of itraconazole was found to dissolve in the buffer solution. Our experimental results confirmed that the SAS process is a promising method for the preparation of microparticles of water-insoluble drug/cyclodextrin inclusion complexes.

Directed Mutagenesis of the Bacillus thuringiensis Cry11A Toxin Reveals a Crucial Role in Larvicidal Activity of Arginine-136 in Helix 4

  • Angsuthanasombat, Chanan;Keeratichamreon, Siriporn;Leetacheewa, Somphob;Katzenmeier, Gerd;Panyim, Sakol
    • BMB Reports
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    • v.34 no.5
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    • pp.402-407
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    • 2001
  • Based on the currently proposed toxicity model for the different Bacillus thuringiensis Cry $\delta$-endotoxins, their pore-forming activity involves the insertion of the ${\alpha}4-{\alpha}5$ helical hairpin into the membrane of the target midgut epithelial cell. In this study, a number of polar or charged residues in helix 4 within domain I of the 65-kDa dipteranactive Cry11A toxin, Lys-123, Tyr-125, Asn-128, Ser-130, Gln-135, Arg-136, Gln-139 and Glu-141, were initially substituted with alanine by using PCR-based directed mutagenesis. All mutant toxins were expressed as cytoplasmic inclusions in Escherichia coli upon induction with IPTG. Similar to the wild-type protoxin inclusion, the solubility of each mutant inclusion in the carbonate buffer, pH 9.0, was relatively low When E. coli cells, expressing each of the mutant proteins, were tested for toxicity against Aedes aegypti mosquito-larvae, toxicity was completely abolished for the alanine substitution of arginine at position 136. However, mutations at the other positions still retained a high level of larvicidal activity Interestingly, further analysis of this critical arginine residue by specific mutagenesis showed that conversions of arginine-136 to aspartate, glutamine, or even to the most conserved residue lysine, also abolished the wild-type activity The results of this study revealed an important determinant in toxin function for the positively charged side chain of arginine-136 in helix 4 of the Cry11A toxin.

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Improvement of Solubility and Dissolution of Ketoconazole by Inclusion with Cyclodextrin (시클로덱스트린과의 포접에 의한 케토코나졸의 용해성 및 용출 증가)

  • Park, Gee-Bae;Ann, Hong-Jik;Chang, Young-Soo;Seo, Bo-Youn;Lee, Kwang-Pyo
    • Journal of Pharmaceutical Investigation
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    • v.24 no.2
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    • pp.85-94
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    • 1994
  • Inclusion complexes of ketoconazole (KT) with ${\alpha}-$, ${\beta}-cyclodextrin$ (CD) and dimethyl-${\beta}-cyclodextrin$ $(DM{\beta}CD)$ in a molar ratio of 1:2 were prepared by freeze-drying and solvent evaporation methods. The interactions of KT with ${\alpha}-CD$, ${\beta}-CD$ and $DM{\beta}CD$ in aqueous solution and in solid state were investigated by solubility study, infrared (lR) spectroscopy and differential scanning calorimetry (DSC). The stability constant of $KT-DM{\beta}CD$ inclusion complex (lC) was found to be the largest among three inclusion complexes. Clear differences in IR spectra and DSC curves were observed between inclusion complexes and physical mixtures (PM) of KT-CDs. It was also shown by IR spectra and DSC curves that solvent evaporation method might be. superior to the freeze-drying method in preparing the inclusion complexes of KT-CDs. The dissolution rate of KT was markedly increased by inclusion complex formation with CDs in the buffer solution at pH 4.0 and pH 6.8. The mean dissolution time (MDT,min), which represents the rapidity of dissolution, was in the order of $KT-DM{\beta}CD$ IC (3.20) < $KT-{\beta}-CD$ IC (4.36) < $KT-{\alpha}-CD$ IC (6.99) < $KT-{\alpha}-CD$ PM (17.46)< $KT-{\beta}-CD$ PM (19.36) < $KT-{\beta}-CD$ PM (28.53). The dissolution rates of KT-CD ICsprepared by solvent evaporation method were faster than those of KT-CD ICs prepared by freeze-drying method.

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Technical Functional Properties of Water- and Salt-soluble Proteins Extracted from Edible Insects

  • Kim, Tae-Kyung;Yong, Hae In;Jeong, Chang Hee;Han, Sung Gu;Kim, Young-Boong;Paik, Hyun-Dong;Choi, Yun-Sang
    • Food Science of Animal Resources
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    • v.39 no.4
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    • pp.643-654
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    • 2019
  • The amino acid composition, protein quality, and protein functionality of protein solution extracted from three edible insect species were investigated. We used 0.02% ascorbic acid and 0.58 M saline solution to extract water-soluble and salt-soluble proteins from the three insect species. Extracted protein solutions of Tenebrio molitor (TM), Allomyrina dichotoma (AD), and Protaetia brevitarsis seulensis (PB) were divided into six groups, according to species and solubility: WTM, WAD, WPB (water-soluble), and STM, SAD, and SPB (salt-soluble). Defatted TM had the highest protein content, but its protein solubility was the lowest, for both water and saline solutions. Amino acid composition differed by edible insect species and buffer type; SPB had the highest protein quality, followed by WPB. PB had a higher pH than the other species. Color values also differed among species. SPB had abundant high molecular weight proteins, compared with other treatments; and also had the highest foaming capacity, foam stability, and emulsifying capacity. In conclusion, PB is a good source of functional protein compared with the other studied species. Additionally, protein extraction using saline solution is promising as a useful method for improving edible insect protein functionality.

Effects of Glycine soja and hairy vetch supplementation on the nutritional quality of corn silage

  • Jung, Kang Seok;Cho, Hyun Min;Lee, Hyung Suk;Heo, Jung Min;Lee, Soo Kee
    • Korean Journal of Agricultural Science
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    • v.45 no.2
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    • pp.169-176
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    • 2018
  • This study evaluated the effects of Glycine soja (GS) and hairy vetch supplementation on the quality of corn silage. The feeding regimen consisted of a corn silage (Control) and a control supplemented either with 20% GS or 20% hairy vetch with four replicates. All experimental diets were stored for 40 days at room temperature ($20-25^{\circ}C$). The control had a higher (p < 0.05) dry matter level but had a lower level (p < 0.05) of crude protein, crude fat, acid detergent fiber and neutral detergent fiber than any other treatments. Hairy vetch had a higher level (p < 0.05) of acetic acid and butyric acid than any other groups but had a lower level (p < 0.05) of lactic acid than that of the control. A lower silage pH was observed (p < 0.05) in the control compared to the other treatments. The control had lower (p < 0.05) sucrose and fructose concentrations compared to the other treatments. Corn silage supplemented with hairy vetch showed a higher level (p < 0.05) of crude protein and buffer solution protein and a higher ratio of soluble protein to insoluble protein than any of the other groups. Thus, the results of the present study suggest that GS and hairy vetch supplementation of corn silage would be beneficial for maintaining quality and elevating protein levels when compared to the control.