• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.153-159
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• 2013

A mannitol dehydrogenase (MDH; EC 1.1.1.67) gene was cloned from the Sinorhizobium meliloti 1021 (KCTC 2353) genome and expressed in Escherichia coli. It was seen to have an open reading frame consisting of 1,485 bp encoding 494 amino acids (about 54 kDa), which shares approximately 35-55% of amino acid sequence identity with some known long-chain dehydrogenase/ reductase family enzymes. The recombinant S. meliloti MDH (SmMDH) showed the highest activity at $40^{\circ}C$, and pH 7.0 (D-fructose reduction) and pH 9.0 (D-mannitol oxidation), respectively. SmMDH could catalyze the oxidative/reductive reactions between D-mannitol and D-fructose in the presence of $NAD^+/NADH$ as a coenzyme, but not with NADP+/NADPH. These results indicate that SmMDH is a typical $NAD^+/NADH$-dependent mannitol dehydrogenase.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.156-162
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• 2012

A mannitol dehydrogenase (StMDH) gene was cloned from Salmonella typhimurium LT2 (KCTC 2421) and overexpressed in Escherichia coli. It has a 1,467 bp open reading frame encoding 488 amino acids with deduced molecular mass of 54 kDa, which shares approximately 36% of amino acid identity with known long-chain dehydrogenase/reductatse (LDR) family enzymes. The recombinant StMDH showed the highest activity at $30^{\circ}C$, and pH 5.0 and 10.0 for D-fructose reduction and D-mannitol oxidation, respectively. On the contrary, it has no activity on glucose, galactose, xylose, and arabinose. StMDH can catalyze the oxidative/reductive reactions between D-fructose and D-mannitol only in the presence of $NAD^+$/NADH as coenzymes. These results indicate that StMDH is a typical $NAD^+$/NADH-dependent mannitol dehydrogenase (E.C. 1.1.1.67).

• KSBB Journal
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• v.28 no.3
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• pp.213-215
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• 2013

A high-throughput screening strategy was developed to simplify the selection process for improved mannitol producing strain after chemical mutagenesis. Ethylmethyl sulfonate (EMS) was used as a chemical mutagen to alter the fructokinase-I gene which is an essential enzyme to metabolize fructose for growth. Leuconostoc mesenteroides treated with EMS were plated on the modified MRS solid medium containing fructose as a sole carbon source. Strains showing inhibited growth were primarily selected to evaluate the mannitol producing ability. By applying this strategy, L. mesenteroides ATCC 8293 M1, L. mesenteroides ATCC 9135 M3 and L. mesenteroides D1 M3 showed improvement in mannitol production.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1691-1699
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• 2018

A metabolically-engineered Deinococcus radiodurans R1 strain capable of producing phytoene, a colorless $C_{40}$ carotenoid and a promising antioxidant, has been developed. To make this base strain, first, the crtI gene encoding phytoene desaturase was deleted to block the conversion of phytoene to other carotenoids such as lycopene and ${\gamma}$-carotene. This engineered strain produced $0.413{\pm}0.023mg/l$ of phytoene from 10 g/l of fructose. Further enhanced production of phytoene up to $4.46{\pm}0.19mg/l$ was achieved by overexpressing the crtB gene encoding phytoene synthase and the dxs genes encoding 1-deoxy-$\text\tiny{D}$-xylulose-5-phosphate synthase gene, and by deleting the crtD gene. High cell-density culture of our final engineered strain allowed production of $10.3{\pm}0.85mg/l$ of phytoene with the yield and productivity of $1.04{\pm}0.05mg/g$ and $0.143{\pm}0.012mg/l/h$, respectively, from 10 g/l of fructose. Furthermore, the antioxidant potential of phytoene produced by the final engineered strain was confirmed by in vitro DPPH radical-scavenging assay.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.1
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• pp.35-39
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• 1997

Studies on the glucose isomerase produced by alkalophilic Streptomyces sp. B-2. Glucose Isomerase (E. C. 5.3.1.5) which reversibly catalyzes reaction between D-glucose and D-fructose was demonstrated in cell free extracts of alkalophilic Streptomyces sp. B-2 isolated form soil. The maximum enzyme activity was found at glucose concentration 4(g/$\ell$) , xylose concentration 6(g/$\ell$), magnesium ion 1.0(g/$\ell$), yeast extract concentration 2.0(g/$\ell$), peptone concentration 3(g/$\ell$).

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1760-1766
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• 2009

Enzymatic syntheses of water soluble Bakuchiol glycosides were carried out in di-isopropyl ether organic media using amyloglucosidase from Rhizopus mold. The reactions were carried out under conventional reflux conditions and in supercritical $CO_2$ atmospheric conditions. Out of the eleven carbohydrate molecules employed for the reaction, D-glucose, D-ribose and D-arabinose gave glycosides in yields of 9.0% to 51.4% under conventional reflux conditions. Under supercritical $CO_2$ atmosphere (100 bar pressure at 50 ${^{\circ}C}$), bakuchiol formed glycosides with Dglucose, D-galactose, D-mannose, D-fructose, D-ribose, D-arabinose, D-sorbitol and D-mannitol in yields ranging from 9% to 46.6%. Out of the bakuchiol glycosides prepared, 6-O-(6-D-fructofruranosyl)bakuchiol showed the best antioxidant (1.4 mM) and ACE inhibitory activities (0.64 mM).

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.210-215
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• 2006

Diplodia gossypina ATCC10936 produced chiral specific (+)-jasmonic acid (JA) that is the most biologically active form. (+)-JA is a plant growth hormone and also one of the most important aroma compounds responsible for jasmin-like aroma note. In order to develop a commercial bioprocess for the production of (+)-JA, optimal culture conditions for D. gossypina ATCC10936 were investigated. D. gossypina produced (+)-JA using either fructose and glucose as a sole carbon source. As a nitrogen source, $NaNO_3$ gave relatively high (+)-JA production. The optimal temperature for the production of (+)-JA by D. gossypina was $28^{\circ}C$, and optimal agitation was found to be 200 rpm. D. gossypina produced (+)-JA upto 600 mg/L in SM medium, although the highest level of biomass was obtained in PDMYS medium.

• Journal of Life Science
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• v.25 no.7
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• pp.819-825
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• 2015

The use of fructose-containing sports beverage drinks has increased in recent years, especially at sport events, because of their reported ergogenic effects. However, the ingestion of low to moderate doses of caffeinated energy drinks has been associated with adverse side effects such as insomnia or increased nervousness. The purpose of this study was to investigate the effects of fructose beverage supplementation on cardiopulmonary function, blood lactate levels, and inflammatory reactions. We recruited 8 young adult subjects from D university and measured their cardiopulmonary functions before and after supplementation with sports beverage drinks. We also measured blood lactate and inflammatory reactions after a 20 min recovery period. Exercise time, maximal oxygen uptake (V0₂max), and AT HRmax were significantly increased (p<0.05) in the period of before and after sports beverage supplementation. However, no significant differences were observed in RPE, AT RER, V0₂max RER, AT V0₂max, and maximum heart rate (HRmax). Lactate levels also significantly decreased after 20 min recovery with sports beverage supplementation. Sports beverage supplementation therefore may enhance maximal V0₂max and increase the exercise duration time. These drinks may also be helpful in promoting rapid recovery of fatigue variables and increasing exercise performance time.

• Food Science and Preservation
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• v.13 no.5
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• pp.661-667
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• 2006

This study was carried out to analyze the major chemical component of the leaf and stem of dried Petasites japonicus S. et Z. Max.. Comparing proximate composition of leaf and stem of Petasites japonicus as dry matter basis, stem contained higher moisture, crude fat, crude ash and carbohydrate, with less crude protein. The main component of free sugar and disaccharide in both leaf and stem were fructose and sucrose, respectively. Total amino acids of leaf and stem were 6,853.32 mg% and 2,350.61 mg% respectively. Although the amino acid composition of leaf and stem were different glutamic acid and aspartic acid were the major amino acids in samples. The major fatty acids of total lipids were linolenic acid in leaf and linoleic acid in stem. The ratios of unsaturated fatty acids to saturated fatty acid were 3.93 in leaf and 3.44 in stem. The unsaturated fatty acid content of samples were 3 times higher than those of saturated fatty acid contents. Oxalic acid was the major organic acids in leaf and stem. The contents of vitamin A, C and E were higher in leaf than in stem. The mined compositions of both leaf and stem were composed in order of K, Mg, Ca, Fe, Na, and Zn.

• Journal of Life Science
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• v.27 no.7
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• pp.849-856
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• 2017

The ${\beta}$-D-fructofuranosidase (EC 3.2.1.26) is an important enzyme from a historical point of view, discovered by French biologist Berthelot in 1860 and was first used to study enzymology. ${\beta}$-D-fructosfuranosidase catalyzes the hydrolysis of sucrose into D-glucose and D-fructose. Four biochemical subgroups of ${\beta}$-D-fructofuranosidase have been investigated in plants. There are vacuolar (soluble acid), cytoplasmic (soluble alkaline), membrane-bound (insoluble alkaline), and cell wall-bound (insoluble acid) ${\beta}$-D-fructofuranosidase by purification. Their biochemical characteristics are distinct. It suggested that those enzymes might be different gene products. The contribution of each of these enzymes to sucrose management in the plant is likely to be correlated with their localization. Common localization in developing cells in tissues from a range of developmental stages and plant parts suggests that all of the isoforms may be closely involved in nutrient transport. The ${\beta}$-D-fructofuranosidases were most commonly found associated with maturing tissues in developing fruits, leaves, and roots. The ${\beta}$-D-fructofuranosidase activity varies in the relationship between growth and expansion through cell division, development of storage organs and tissues, and the relationship of plant defense responses. It is necessary to summarize more researches in order to know the definite physiological function.