• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.447-454
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• 1999

The production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS) are known to be modulated by a variety of factors. Recent study showed that endotoxin-induced NO synthesis and iNOS expression were greatly enhanced by elevation of extracellular glucose concentration in murine macrophages. Although this was suggested to be due to the activation of protein kinase C (PKC) via sorbitol pathway, there was lack of evidence for this speculation. This study was performed to delineate the underlying intracellular mechanisms of glucose-enhancing effect on endotoxin-induced NO production in Raw264.7 macrophages. The levels of NO release induced by lipopolysaccharide (LPS) significantly increased by the treatment of glucose in a concentration dependent manner and also, this effect was observed in LPS-preprimed cells. Concurrent incubation of cells with PKC inhibitors, H-7 or chelerythrine, and LPS resulted in the diminution of NO production regardless of glucose concentration but this was not in the case of LPS-prepriming, that is, chelerythrine showed a minimal effect on the glucose- enhancing effect. PMA, a PKC activator, did not show any significant effect on glucose-associated NO production. Modulation of sorbitol pathway with zopolrestat, an aldose reductase inhibitor, did not affect LPS-induced NO production and iNOS expression under high glucose condition. And also, sodium pyruvate, which is expected to normalize cytosolic $NADH/NAD^+$ ratio, did not show any significant effect at concentrations of up to 10 mM. Glucosamine marginally increased the endotoxin-induced nitrite release in both control and high glucose treated group. 6-diazo-5-oxonorleucine (L-DON) and azaserine, glutamine: fructose- 6-phosphate amidotransferase (GFAT) inhibitors, significantly diminished the augmentation effect of high glucose on endotoxin-induced NO production. On the other hand, negative modulation of GFAT inhibitors was not reversed by the treatment of glucosamine, suggesting the minimal involvement, if any, of glucosamine pathway in glucose-enhancing effect. In summary, these results strongly suggest that the hexosamine biosynthesis pathway and the activation of PKC via sorbitol pathway do not contribute to the augmenting effect of high glucose on endotoxin induced NO production in macrophage-like Raw264.7 cells.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.432-437
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• 2014

This study was carried out to examine the quality properties of honey in Korean commercial markets. The moisture content, stable carbon isotope ratio, invert sugar, cane sugar, and hydroxy-methylfurfural (HMF) contents of honey were measured according to the Korea Food Code and AOAC's (Association of Official Analytical Chemists) official methods. The stable carbon isotope ratio ranged from -25.18‰ to -12.60‰, which clearly differed between honey of $C_3$ origin (flower) and $C_4$ origin (artificial). Results of quality measurements revealed a moisture content of 18.12 to 19.70%, fructose content of 36.10 to 43.94%, glucose content of 22.61 to 31.91%, sucrose content of 1.56 to 4.75%, invert sugar content of 64.89 to 72.79%, and HMF content of 4.10 to 78.66 mg/kg. These values demonstrate that the quality of the tested honey meets the standard criteria of the Korean Food Code and Codex. However, it is necessary to reconsider the appropriate criteria for imported honey because it is circulated in the market through a long distribution process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.190-195
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• 1993

In order to investigate the changes of some chemical components during the maturation of Vitis vinifera red grapes, brix, total sugar, organic acids, total acid, pH and free amino acids were analyzed by HPLC etc. Brix, pH and total sugar content during the maturation of red grapes were increased rapidly but total acidity was decreased between 12~14 days after the formation of sugars. Its compositions were 16.5~17.9 of brix, 14.8~16.4g/100ml of total sugar, 3.24~3.25 of pH and 0.81~0.92g/100ml of total acidity. The ratio of brix/acid was increased gradually during the maturation. Glucose and fructose were contained more than 99% of total sugar and the content of sucrose were 0.03~0.04g/100ml in three varieties (Cabernet sauvignon, Cabernet franc and Malbec). The ratio of fructose/glucose in maturated three red grapes was ranged 1.04~1.06. Organic acids during the maturation, when sugars increased, were decreased rapidly and the ratio of tartaric/malic acid showed 0.83~1.00. Free amino acids during the maturation were increased and these content were 256.8mg~290.9mg/100ml in three varieties. The content of proline was the highest content of free amino acids in three red grapes, the next ones were arginine, alanine and glutamic acid in the other with 73.2~77.2% of total free amino acids. Especially, content of arginine was higher than others in Malbec variety.

• BMB Reports
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• v.38 no.5
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• pp.584-590
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• 2005

Glucose 6-phosphate dehydrogenase (EC 1.1.1.49) was purified from Aspergillus aculeatus, a filamentous fungus previously isolated from infected tongue of a patient. The enzyme, apparently homogeneous, had a specific activity of $220\;units\;mg^{-1}$/, a molecular weight of $105,000{\pm}5,000$ Dal by gel filtration and subunit size of $52,000{\pm}1,100$ Dal by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The substrate specificity was extremely strict, with glucose 6-phosphate (G6P) being oxidized by nicotinamide adenine dinucleotide phosphate (NADP) only. At assay pH of 7.5, the enzyme had $K_m$ values of $6\;{\mu}m$ and $75\;{\mu}m$ for NADP and G6P respectively. The $k_{cat}$ was $83\;s^{-1}$. Steady-state kinetics at pH 7.5 produced converging linear Lineweaver-Burk plots as expected for ternary-complex mechanism. The patterns of product and dead-end inhibition suggested that the enzyme can bind NADP and G6P separately to form a binary complex, indicating a random-order mechanism. The enzyme was irreversibly inactivated by heat in a linear fashion, with G6P providing a degree of protection. Phosphoenolpyruvate (PEP), adenosinetriphosphate (ATP), and fructose 6-phosphate (F6P), in decreasing order, are effective inhibitors. Zinc and Cobalt ions were effective inhibitors although cobalt ion was more potent; the two divalent metals were competitive inhibitors with respect to G6P, with $K_i$ values of $6.6\;{\mu}m$ and $4.7\;{\mu}m$ respectively. It is proposed that inhibition by divalent metal ions, at low NADPH /NADP ratio, is another means of controlling pentosephosphate pathway.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.497-503
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• 1983

This study was conducted to define the effects of light intensity on the amount of saponin and free sugar and the ratio of triol group saponin and diol group saponin (PT/PD) in the leaf of Panax ginseng C.A. Meyer. 4-Year-old ginseng plants were grown under the shadings of different light transmittance rate(LTR) of 5%, 10%, 20% and 30% for 5 months and the leafiets were sampled from 2nd low at late August to determine the amount of saponin and free sugar.-Rd was main ginseuoside in the diol group saponin but in triol group saponin, ginsenoside-Re showed highest value and next was ginsenoside-$Rg_1$ and $Rg_2$ respectively. Up to 20% of light transmittance rate (LTR), the ginseng leaves grown under high light intensity showed an increase in the amount of total saponin and the ratio of PT/PD but the amount of total saponin and the ratio of PT/PD but the amount of total saponin and the ratio of PT/PD was decreased at the ginseng leaves grown under the shading of 30% LTR. The ginseng leaves grown under the shading of 20% LTR showed a significant increase in the amount of glucose and fructose but a significant decrease of sucrose content. A significant positive correlation ($r=0.992$^{**}$) was recognized between the of amount of total saponin and glucose.

• Food Science and Preservation
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• v.8 no.2
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• pp.169-174
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• 2001

Chemical analysis and optimum preparation conditions for fig jam were investigated. Soluble solids, acid content and vitamin C of fig was 12.20。Brix, 0.14% and 2.27 mg/100g, respectively. Carbohydrate in fig juice was consisted of 54.43% glucose and 44.53% fructose. Potassium content of fig was 178.0 mg/100g. Moisture content and total sugar of fig fruit was 88.35% and 9.47%. In preparation of fig jam, the addition of 0.2% Citrus natsudaidai juice and 0.5% C. lemon juice as acid source was the best in regard with color and flavor determined by sensory evaluation. The ratio of sucrose : honey : oligo sugar(70:20:10) was also the best in addition of sugar source 60%(w/w) in total. Fig jam prepared in this experiment was better than that of commercial products in sensory evaluation, and microbial growth of this product was not recognized for one month at 30$\^{C}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.950-953
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• 1994

This study was carried out to investigate the proximate composition , free sugars,amino acids, organic acid, minerals and extracted color of the fruit of paper mulberry (Broussonetia Kazinoki Siebold) . the proximate compositins were 6.1% of moisture, 15.9% of crude protein, 28.5% of crude fat, 8.9% of crude ash and 40.6% of carbohydrates in the fruit of paper mulberry. Free sugars showed low content as 0.1% of glucose , 0.1% of sucrose, 0.1% of fructose and 0.01% of sorbitol, respectively. In amino acid composition of the fruit of paper mulberry, glycine was the highest in the content, followed by methionine, aspartic acid and alanine, The ratio of essential /total mino acids was 0.43 . The richestmineral contained in the fruit of paper mulberry was Ca and followed by K and Mg. Optical density (490-500nm) of the extracted color with 50% ehtanol and 80 % ethanol were 0.75 and 0.30 , respectively.

• Journal of Mushroom
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• v.14 no.1
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• pp.6-13
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• 2016

This study was carried out to determine the basic mycelial culture conditions for Poria cocos growth. According to colony diameter and mycelial density, suitable media for mycelial growth were Malt yeast extract, Potato dextrose agar, Yeast extract agar, and Yeast malt agar. The optimum temperature for mycelial growth was between 25 and $35^{\circ}C$, and the optimum pH value was between 4 and 7. Carbon and nitrogen sources were fructose and yeast extract. The optimum C/N ratio was about 10 to 1 with 2% glucose. Other minor components for optimal growth were thiamine-HCl and nicotinamide as vitamins, acetic and lactic acid as organic acids, and $MgSO_4{\cdot}7H_2O$ and $FeSO_4{\cdot}7H_2O$ as mineral salts.

• Journal of Ginseng Research
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• v.9 no.1
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• pp.104-111
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• 1985

The quality of concentrated red ginseng extract, which was prepared from Korean red ginseng tails, was studied with respect to the changes in the ethanol concentration in the range of 0-90% and temperature of 70-10$0^{\circ}C$ during 1-5 times of extraction. Each extraction time was taken 8 hours at given temperature. The ratio of free sugars to total sugar changed significantly with the number of extraction and ethanol concentrations. An increase in reducing sugar and free sugars and a decrease in extracted soluble starch were fond as ethanol concentration increased. Extraction temperature was found little effect on extractability of sugars and their ratios. Analysis of free sugars in red ginseng extract identified 6 frdd sugars such as rhamnose, xylose, fructose, glucose, sucrose and maltose, including sucrose to be major.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.233-238
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• 2000

To develop biodegradable and safe flocculant, Achromobacter sp. HY-66 were isolated from soil. The purified flocculant was composed of fructose and glucose in an approximate molar ratio of 1:24. Molecular weight was approximately 9$\times$105 dalton by Sepharose CL-4B gel filtration chromatography. Elemental analysis revealed that the contents of carbon, hydrogen and oxygen were 37.72%, 5.37% and 56.89%, respectively. The presence of O-H stretching, C-H streching, carboxy ester and C-H bending were confirmed by IR absorption spectrum analysis. We suggest that a bioflocculant produced from Achromobacter sp. YJ-66 is new and different from other bioflocculants.