• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.310-315
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• 1995

The heterobimetallic anion, (OC)5CrMn(CO)5-M+ (M+=Na+, PPN+), which has a donor-acceptor metal-metal bond1, was reacted with allyl bromide to yield BrCr(CO)5- and Mn(CO)5(CH2CHCH2). The reaction mechanism has been proposed in terms of the consecutive reaction pathway in which Cr(CO)5(THF) is an important intermediate leading to the corresponding product. Counterion effect on this reaction was also evaluated and the results were compared with those of the corresponding reaction of the mononuclear carbonyl anion, Mn(CO)5-.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.325-329
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• 2006

Leuconostoc mesenteroides B-742 fermentations with maltose as an acceptor were tested for glucooligosaccharides and mannitol co-production. Leuconostoc oligosaccharides were produced that were oligomers with a size range of DP 2 to 7 and were primarily DP 3, 4, 5, and 6, containing mainly ${\alpha}-1,4$ and ${\alpha}-1,6$ linkages. Maltose was linked to the reducing end of the isomaltosyl residues. The $Ca^{2+}$ form of cation-exchange column could separate glucooligosaccharides from byproducts.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.187-194
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• 1998

Glycosides were synthesized using transglycosylation reaction of amylase in water system. Starch as a glycosyl donor and benzylalcohol as an acceptor were selected as substrates of transglycosylation reaction. Among tested 9 commercial amylase, amyloglucosidase from Rhizopus sp. had high activity for transglycosylation from starch. The glycoside synthesized in water phase by amyloglucosidase was identified as benzylalcohol-${alpha}$-glucoside (BG) of which one molecule of benzylalcohol was bound to 1-OH of glucose. The transglycosylation reaction by amyloglucosidase were carried out in reaction system containing 50 mg starch, 50 mg benzylalcohol, and 10 units enzyme in pH 5.0 at 45$^{\circ}C$. The synthesized BG was hydrolyzed by ${alpha}$-glucosidase to produce glucose and benzylalcohol.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.127-131
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• 1999

Anaerobically grown cells of an Fe(III)-reducing bacterium, Shewanella putrefaciens IR-l, were electrochemically active with an apparent reduction potential of about 0.15 V against a saturated calomel electrode in the cyclic voltammetry. The bacterium did not grow fermentatively on lactate, but grew in an anode compartment of a three-electrode electrochemical cell using lactate as an electron donor and the electrode as the electron acceptor. This property was shared by a large number of Fe(III)-reducing bacterial isolates. This is the first observation of a direct electrochemical reaction by an intact bacterial cell, which is believed to be possible due to the electron carrier(s) located at the cell surface involved in the reduction of the natural water insoluble electron acceptor, Fe(III).

• Journal of the Korean Chemical Society
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• v.60 no.5
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• pp.374-377
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• 2016

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1998.06a
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• pp.302.2-303
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• 1998

• Bulletin of the Korean Chemical Society
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• v.22 no.3
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• pp.257-258
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• 2001

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.432.2-432.2
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• 2016

A new A-D-A type (Acceptor-Donor-Acceptor) conjugated based on pyridine-borane complex (Donor), non-boron fluorine (Donor) and 2,5-bis(alkyl)-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (DPP) (Acceptor) were designed and synthesized via Pd-catalyzed Suzuki cross-coupling reaction. The synthesized boron based complex exhibited high electron affinity, which indicates deep HOMO energy levels and good visible absorption led to their use as donors in BHJ (bulk heterojunction) solar cells. Inverted devices were fabricated, reaching open-circuit voltage as high as 0.91eV. To probe structure-property relationship and search for design principle, we have synthesized pyridine-boron based electron donating small molecules. In this study, we report a new synthetic approach, molecular structure, charge carrier mobility and morphology of blended film and their correlation with the photovoltaic J-V characteristics in details.

• KSBB Journal
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• v.19 no.5
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• pp.363-367
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• 2004

Leuconostoc mesenteroides NRRL B-1149 produces various glucoseyltransferases for the synthesis of dextran, levan and glucose-1-phosphate using sucrose as a substrate. A sucrose phosphorylase (1149SPase) was purified from L. mesenteroides NRRL B-1149 culture by using hollow fiber filtration (30 kDa cut off), Toyopearl DEAE 650 M column chromatography and following two times of DEAE-Sepharose column chromatographies. The specific activity of the purified 1149SPase was 25.7 (U/mg) with $16\%$ yield. The 1149SPase showed a molecular size of 56 kDa on denatured $10\%$ SDS-PAGE. The N-terminal amino acid sequence of the enzyme was MEIQNKAM. The optimum pH and temperature of this enzyme were 6.2~6.5 and 37^{circ}C, respectively. It had an apparent K_{m} of 6.0 mM and K_{cat} of 1.62/s for sucrose. 1149SPase crystal was formed by hanging drop diffusion technique using 20 mM calcium chloride dihydrate, 100 mM sodium acetate trihydrate pH 4.6 and $30\%$ 2-methyl-2,4-pentanediol as vaporizing and reservation solution. The 1149SPase catalyzes transferring of glucose from isomaltose or sucrose to salicin and salicyl alcohol by disproportionation reaction or acceptor reaction and synthesized two acceptor products, respectively.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.46-52
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• 2002

As a functional additive for intestinal microflora, panose ($6^2-{\alpha}$-D-glucopyranosylmaltose) was synthesized during kimchi fermentation using the glucose transferring reaction of glucansucrase from Leuconostoc mesenteroides. For the glucose transferring reaction, sucrose and maltose were added ($2\%$ each, w/v) to dongchimi-kimchi as the glucosyl donor and acceptor molecule, respectively. After five days of incubation at $10^{\circ}C$, referring to the initial phase for the production of lactic acid in kimchi, over $60\%$ (w/v) of the total sugars were converted into panose and other branched oligosaccharides. Thereafter, the kimchi was stored at $4^{\circ}C$ and the amount of panose remained at a constant level for three weeks, thereby indicating the stability of panose to microbial degradation during the period of kimchi consumption. The use of maltose as the acceptor molecule in the kimchi also facilitated a lower viscosity in the kimchi-juice by preventing the synthesis of a dextran-like polymer which caused an unfavorable taste. Accordingly, the application of this new method of simultaneous biocatalytic synthesis of oligosaccharides during lactate fermentation should facilitate the extensive development of new function-added lactate foods.