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Park HS, Lee YC, Choi BG, Hong WH, Yang JW. Clean and facile solution synthesis of iron(III)-entrapped gamma-alumina nanosorbents for arsenic removal. CHEMSUSCHEM 2008; 1:356-362. [PMID: 18605102 DOI: 10.1002/cssc.200700119] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Iro (III)-entrapped gamma-alumina nanosorbents were prepared by an environmentally benign method using an ionothermal process based on an ionic liquid to synthesize the gamma-alumina host and a sonochemical method to entrap the iron(III) guest. The morphology of the alumina depends on the aluminum precursor used, giving aligned bundled and randomly debundled gamma-alumina nanorods as well as wormlike mesoporous alumina. In particular, the rodlike structure shows significantly greater mesoporosity than the wormlike porous gamma-alumina structure. Moreover, entrapment of iron(III) in the gamma-alumina nanosorbents with randomly debundled rodlike structures leads to the greatest AsV removal capacity and the fastest adsorption rate as compared to the other FeIII-entrapped adsorbents, as a result of its larger surface area and pore sizes. Thus, this method provides a clean and effective route to an advanced host-guest adsorbent system for application in the removal of arsenic from drinking water.
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Park HS, Choi YS, Jung YM, Hong WH. Intermolecular Interaction-Induced Hierarchical Transformation in 1D Nanohybrids: Analysis of Conformational Changes by 2D Correlation Spectroscopy. J Am Chem Soc 2007; 130:845-52. [DOI: 10.1021/ja073074k] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Song H, Lee JW, Choi S, You JK, Hong WH, Lee SY. Effects of dissolved CO2 levels on the growth ofMannheimia succiniciproducens and succinic acid production. Biotechnol Bioeng 2007; 98:1296-304. [PMID: 17570706 DOI: 10.1002/bit.21530] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A capnophilic rumen bacterium Mannheimia succiniciproducens produces succinic acid as a major fermentation end product under CO(2)-rich anaerobic condition. Since succinic acid is produced by carboxylation of C3 compounds during the fermentation, intracellular CO(2) availability is important for efficient succinic acid formation. Here, we investigated the metabolic responses of M. succiniciproducens to the different dissolved CO(2) concentrations (0-260 mM). Cell growth was severely suppressed when the dissolved CO(2) concentration was below 8.74 mM. On the other hand, cell growth and succinic acid production increased proportionally as the dissolved CO(2) concentration increased from 8.74 to 141 mM. The yields of biomass and succinic acid on glucose obtained at the dissolved CO(2) concentration of 141 mM were 1.49 and 1.52 times higher, respectively, than those obtained at the dissolved CO(2) concentration of 8.74 mM. It was also found that the additional CO(2) source provided in the form of NaHCO(3), MgCO(3), or CaCO(3) had positive effects on cell growth and succinic acid production. However, growth inhibition was observed when excessive bicarbonate salts were added. By the comparison of the activities of key enzymes, it was found that PEP carboxylation by PEP carboxykinase (PckA) is the most important for succinic acid production as well as the growth of M. succiniciproducens by providing additional ATP.
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Jun YS, Lee EZ, Huh YS, Hong YK, Hong WH, Lee SY. Kinetic study for the extraction of succinic acid with TOA in fermentation broth; effects of pH, salt and contaminated acid. Biochem Eng J 2007. [DOI: 10.1016/j.bej.2006.06.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Song H, Huh YS, Lee SY, Hong WH, Hong YK. Recovery of succinic acid produced by fermentation of a metabolically engineered Mannheimia succiniciproducens strain. J Biotechnol 2007; 132:445-52. [PMID: 17765349 DOI: 10.1016/j.jbiotec.2007.07.496] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2007] [Revised: 06/12/2007] [Accepted: 07/03/2007] [Indexed: 11/26/2022]
Abstract
There have recently been much advances in the production of succinic acid, an important four-carbon dicarboxylic acid for many industrial applications, by fermentation of several natural and engineered bacterial strains. Mannheimia succiniciproducens MBEL55E isolated from bovine rumen is able to produce succinic acid with high efficiency, but also produces acetic, formic and lactic acids just like other anaerobic succinic acid producers. We recently reported the development of an engineered M. succiniciproducens LPK7 strain which produces succinic acid as a major fermentation product while producing much reduced by-products. Having an improved succinic acid producer developed, it is equally important to develop a cost-effective downstream process for the recovery of succinic acid. In this paper, we report the development of a simpler and more efficient method for the recovery of succinic acid. For the recovery of succinic acid from the fermentation broth of LPK7 strain, a simple process composed of a single reactive extraction, vacuum distillation, and crystallization yielded highly purified succinic acid (greater than 99.5% purity, wt%) with a high yield of 67.05wt%. When the same recovery process or even multiple reactive extraction steps were applied to the fermentation broth of MBEL55E, lower purity and yield of succinic acid were obtained. These results suggest that succinic acid can be purified in a cost-effective manner by using the fermentation broth of engineered LPK7 strain, showing the importance of integrating the strain development, fermentation and downstream process for optimizing the whole processes for succinic acid production.
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Huh YS, Jun YS, Hong YK, Hong WH, Kim DH. Microfluidic separation of (S)-ibuprofen using enzymatic reaction. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.molcatb.2006.06.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Park HS, Kim YJ, Hong WH, Lee HK. Physical and electrochemical properties of Nafion/polypyrrole composite membrane for DMFC. J Memb Sci 2006. [DOI: 10.1016/j.memsci.2005.07.019] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Jun YS, Huh YS, Hong WH, Hong YK. Kinetics of the extraction of succinic acid with tri-n-octylamine in 1-octanol solution. Biotechnol Prog 2006; 21:1673-9. [PMID: 16321050 DOI: 10.1021/bp050083t] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Kinetic studies for the extraction of succinic acid from aqueous solution with 1-octanol solutions of tri-n-octylamine (TOA) were carried out using a stirred cell with a microporous hydrophobic membrane. The interfacial concentrations of species were correlated and thus the intrinsic kinetics was obtained. The overall extraction process was controlled by the chemical reaction at or near the interface between the aqueous and organic phases. The formation reaction of succinic acid-TOA complex was found to be first order with respect to the concentration of succinic acid in the aqueous phase and the order of 0.5 with respect to that of TOA in the organic phase with a rate constant of (3.14 +/- 0.6) x 10(-8) m(2.5) x mol(-0.5) x s(-1). The dissociation reaction of succinic acid-TOA complex was found to be the second-order with respect to that of succinic acid-TOA complex in the organic phase and the order of -2 with respect to that of TOA in the organic phase with a rate constant of (1.44 +/- 1.4) x 10(-4) mol x m(-2) x s(-1).
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Park H, Kim Y, Hong WH, Choi YS, Lee H. Influence of Morphology on the Transport Properties of Perfluorosulfonate Ionomers/Polypyrrole Composite Membrane. Macromolecules 2005. [DOI: 10.1021/ma047650y] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Huh YS, Hong YK, Hong WH, Chang HN. Selective extraction of acetic acid from the fermentation broth produced by Mannheimia succiniciproducens. Biotechnol Lett 2004; 26:1581-4. [PMID: 15604800 DOI: 10.1023/b:bile.0000045656.00138.93] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Acetic acid is by-product from fermentation processes for producing succinic acid using Mannheimia succiniciproducens . To obtain pure succinic acid from the final fermentation broth, acetic acid was selectively removed based on the different extractability of succinic acid and acetic acid with pH using tri-n-octylamine (TOA) as extractant. When successive batch extractions were performed using 0.25 mol TOA kg(-1) dissolved in 1-octanol at pH 5, the mol ratio of succinic acid to acetic acid before extraction was 4.9 and the final ratio after the fourth batch was 9.4.
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Choi WC, Jeon MK, Kim YJ, Woo SI, Hong WH. Development of enhanced materials for direct-methanol fuel cell by combinatorial method and nanoscience. Catal Today 2004. [DOI: 10.1016/j.cattod.2004.06.108] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Kim YJ, Choi WC, Woo SI, Hong WH. Evaluation of a palladinized Nafion™ for direct methanol fuel cell application. Electrochim Acta 2004. [DOI: 10.1016/j.electacta.2004.02.037] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Hahm HC, Lee DW, Hong WH, Lee TY, Lee CH. Predispersed solvent extraction of negatively complexed copper from water using colloidal liquid aphron containing a quaternary ammonium salt. KOREAN J CHEM ENG 2003. [DOI: 10.1007/bf02706914] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kim BS, Hong YK, Hong WH. Effect of ph on the extraction characteristics of succinic acid and the stability of colloidal liquid aphrons. KOREAN J CHEM ENG 2002. [DOI: 10.1007/bf02699315] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lee DW, Hong WH, Lee TY, Lee CH. Influence of continuous aqueous phase on the preparation and stability of colloidal liquid aphrons. SEP SCI TECHNOL 2002. [DOI: 10.1081/ss-120003050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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66
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Yoon JH, Chun MK, Hong WH, Lee H. High-pressure phase equilibria for carbon dioxide-methanol-water system: experimental data and critical evaluation of mixing rules. Ind Eng Chem Res 2002. [DOI: 10.1021/ie00023a061] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hong YK, Han DH, Hong WH. Water enhanced solubilities of succinic acid in reactive extraction using tertiary amines/alcohols systems. KOREAN J CHEM ENG 2002. [DOI: 10.1007/bf02706878] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Tang SF, Chen CK, Hsu R, Chou SW, Hong WH, Lew HL. Vastus medialis obliquus and vastus lateralis activity in open and closed kinetic chain exercises in patients with patellofemoral pain syndrome: an electromyographic study. Arch Phys Med Rehabil 2001; 82:1441-5. [PMID: 11588751 DOI: 10.1053/apmr.2001.26252] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVES To evaluate the electromyographic activities of vastus medialis obliquus (VMO) and vastus lateralis (VL) muscles in open and closed kinetic chain exercises in subjects with patellofemoral pain syndrome (PFPS). DESIGN Case-controlled study. SETTING Rehabilitation science center in a tertiary medical center. PARTICIPANTS Ten patients with bilateral knee pain diagnosed with PFPS and 10 healthy volunteers. INTERVENTIONS Subjects performed open kinetic chain exercise on an isokinetic dynamometer and closed kinetic chain exercise by squat-to-stand and stand-to-squat tasks. Surface electromyography was done for the VMO and VL muscles. MAIN OUTCOME MEASURES VMO/VL ratios were calculated after normalization of muscle activities. RESULTS The VMO/VL ratios of PFPS subjects were significantly lower than were those of unimpaired subjects during knee isokinetic closed kinetic chain exercises (p = .047). However, there was no statistical difference in VMO/VL ratio between subjects with and without PFPS during closed kinetic chain exercises (p = .623). Maximum VMO/VL ratio was obtained at 60 degrees knee flexion in closed kinetic chain exercise. CONCLUSION In closed kinetic chain exercises, more selective VMO activation can be obtained at 60 degrees knee flexion. Maximal VMO/VL ratio was observed at this knee flexion angle, and muscle contraction intensity was also greatest.
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Lee CH, Hong WH. Effect of operating variables on the flux and selectivity in sweep gas membrane distillation for dilute aqueous isopropanol. J Memb Sci 2001. [DOI: 10.1016/s0376-7388(01)00373-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Park DM, Hong WH, Kim SG, Kim HJ. Heat generation of filled rubber vulcanizates and its relationship with vulcanizate network structures. Eur Polym J 2000. [DOI: 10.1016/s0014-3057(00)00020-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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72
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Han DH, Hong YK, Hong WH. Separation characteristics of lactic acid in reactive extraction and stripping. KOREAN J CHEM ENG 2000. [DOI: 10.1007/bf02707161] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Wong AM, Chen CL, Hong WH, Tang FT, Lui TN, Chou SW. Motor control assessment for rhizotomy in cerebral palsy. Am J Phys Med Rehabil 2000; 79:441-50. [PMID: 10994886 DOI: 10.1097/00002060-200009000-00007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To apply motor control assessment for selection of appropriate spastic cerebral palsy children to receive selective posterior rhizotomy (SPR). DESIGN Forty children with spastic cerebral palsy (3-16 yr) were divided into three groups: "independent ambulator," "dependent ambulator," and "nonambulator." Another 18 healthy children were selected as the control group. Both motor control (tested by using polyelectromyography (PEMG)) and clinical ambulatory capability were assessed within 1 mo before SPR and 12 mo after. PEMG patterns were classified into seven patterns according to electromyographic activities during hip/knee flexion and extension. Gait patterns, which were analyzed by computer DynoGraphy, were classified into four patterns for children with ambulatory capability. RESULTS PEMG and gait patterns were correlated with ambulatory ability. PEMG patterns 2-3 could predict independent ambulatory ability, whereas patterns 6-7 will interfere with ambulatory ability. PEMG patterns showed significant improvement after SPR in the ambulatory groups (P < 0.05), whereas they did not improve in the nonambulator group. Children with cerebral palsy with co-contraction of proximal/distal muscles had better results after SPR, whereas those with diffuse co-contraction or reduced electromyography activities had poor results. CONCLUSIONS PEMG patterns may allow the physician to select the appropriate children with spastic cerebral palsy to receive SPR with good results.
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Hong YK, Hong WH. Equilibrium studies on reactive extraction of succinic acid from aqueous solutions with tertiary amines. Bioprocess Biosyst Eng 2000. [DOI: 10.1007/s004499900090] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chen IC, Cheng PT, Hu AL, Liaw MY, Chen LR, Hong WH, Wong MK. Balance evaluation in hemiplegic stroke patients. CHANG GUNG MEDICAL JOURNAL 2000; 23:339-47. [PMID: 10958036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Decreased equilibrium in standing and walking is a common problem associated with hemiplegic stroke patients. Stroke patients with balance problems are prone to falls. In addition to spatial recognition, the appropriate pattern of muscle activity to preserve balance depends on sensory and motor processes. Previous reports have mentioned that the right posterior parietal cortex seems to be predominantly involved in spatial integration. We therefore wanted to conduct a study to quantify and compare the balance control between right hemispheric stroke and left hemispheric stroke patients. METHODS Thirty hemiplegic stroke patients (14 right, 16 left) and 15 age-matched healthy subjects were included in this study. The objective measurement of the basic components of balance control was performed using the SMART Balance Master. The motor status of the hemiplegic limbs was evaluated by Brunnstrom staging. The functional outcome of the stroke patients was evaluated by the functional independence measure (FIM). RESULTS The balance function of stroke patients was significantly worse as compared to that of the healthy subjects especially in dynamic stability. However, different from the other reports, our right hemispheric stroke patients had better balance function than our left hemispheric patients. The locomotion and mobility scores of the FIM were also better in the right hemispheric stroke patients. CONCLUSION This result suggested that the motor function of the healthy limbs of stroke patients may play an important role in their balance function. The results of this study may provide a guide for prescribing a more efficient rehabilitation program for stroke patients.
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