• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1024-1030
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• 1998

We investigated the effects of vitamin E supplementation on protein glycosylation in early and end stage product, and light microscopic studies were done on the renal glomeruli of KK-mice of various ages and various duration of diabetes. Weaned KK-mice were fed high fat diets containing 20% corn oil(wt/wt), and sacrificed at 4,6, and 9 months of age. The high vitamin E diet was a high fit diet supplemented with an excess amount of d1-$\alpha$-tocopheryl acetate (2080IU/kg diet). We measured Hemoglobin $A_{IC}$ (Hb $A_{IC}$) as a glycosylation early product, and renal collagen-linked fluorescence as a glycosylation end product. In the diabetic group, levels of Hb $A_{IC}$ were increased within 2 months after onset of diabetes and remained at a constant level for the duration of experiment. 5 months after onset of diabetes, renal collagen linked fluorescence(CLF) was markedly increased. A quantative, morphologically demonstratable, progressive thickening of the basement membrane and calcification occured in the diabetic KK-mice. There is a statiscally positive correlation between CLF and histologic grade of diabetic nephropathy. Hepatic vitamin E levels correlated with those of Hb $A_{IC}$, renal CLF, and renal calcification. Treatment with vitamin I did not modify the level of blood glucose. However, we observered a significant lowering of CLF and Hb $A_{IC}$ in diabetic mice. Supplementation of vitamin E was found to delay the progression of diabetic nephropathy. (forean J Nutrition 31(6) : 1024-1030, 1998)0, 1998)

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.1
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• pp.73-78
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• 2009

In order to investigate the potential of a Dayflower (Commelina communis L.) extract as an active in gredient for whitening cosmetics, we prepared aqueous Commelina communis L. extract We measured its mushroom tyrosinase inhibitory activity, cellular tyrosinase activity, and melanin synthesis inhibitory activity in B16 melanoma cells. It did not show inhibitory activity against mushroom tyrosinase but showed melanin synthesis inhibitory activity. In a melanin synthesis inhibition assay using mouse B16-F10 melanoma cell, it suppressed melanin production up to 32% at a concentration of $1,000{\mu}/mL$ without cytotoxicity, and also reduced cellular tyrosinase activity to above 50 % above the concentration of $250{\mu}g/mL$. In study on the melanogenic protein expressions, it had especially influence on expression of tyrosinase protein, which is a well-known key protein on melanogenesis, and tyrosinase expression was gradually decreased in a dose-dependent. Dayflower also blocked N-glycosylation of TRP-2, but affected on the expression of TRP-1 rather than on blocking of N-glycosylation processing. Therefore, this result suggests that aqueous Commelina communis L. extract could be used as an active ingredient for whitening cosmetics.

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.815-818
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• 2005

• Mass Spectrometry Letters
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• v.4 no.1
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• pp.10-17
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• 2013

Recent developments in MS-based glycomics and glycoproteomics have rapidly advanced the field and pushed the boundaries of glyco-analysis into new territories. This review will lay out current workflows and strategies for characterization of the glycoproteome, including (in order of increasing complexity and information content) preliminary site mapping, compositional glycan profiling, isomer-specific glycan profiling, glycosite-specific glycopeptide profiling, and finally, glycoproteomic profiling.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2493-2494
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• 2007

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.731-734
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• 2011

• BMB Reports
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• v.47 no.5
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• pp.256-261
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• 2014

To investigate the function of N-glycosylation of Cel5A (endoglucanase II) from Hypocrea jecorina, two N-glycosylation site deletion Cel5A mutants (rN124D and rN124H) were expressed in Saccharomyces cerevisiae. The weights of these recombinant mutants were 54 kDa, which were lower than that of rCel5A. This result was expected to be attributed to deglycosylation. The enzyme activity of rN124H was greatly reduced to 60.6% compared with rCel5A, whereas rN124D showed slightly lower activity (10%) than that of rCel5A. rN124D and rN124H showed different thermal stabilities compared with the glycosylated rCel5A, especially at lower pH value. Thermal stabilities were reduced and improved for rN124D and rN124H, respectively. Circular dichroism spectroscopy showed that the modification of secondary structure by mutation may be the reason for the change in enzymatic activity and thermal stability.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.74-83
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• 1993

In an attempt toward the synthesis of the difficulty accessible ginseng saponins the four dammarane glycosides identical to the natural $ginsenosides-Rh_2,$ - F2, compound K and chikusetsusaponin - LT8 have been prepared from betulafolienetriol(=dammar-24-ene-$3{\alpha},12{\beta}\;20(S)-triol).\;3-O-{\beta}-D-Glucopyranoside$ of 20(S) - protopanaxadiol $(=ginsenoside-Rh_2)$ have been obtained by the regio - and stereoselective glycosylation of the $12-O-acetyldammar-24-ene-3{\beta},\;12{\beta},$ 20(S)-triol. The 12-ketoderivative of 20(S)-protopanaxadiol has been used as aglycon in synthesis of chikusetsusaponin - LT8. Attempted regio - and stereoselective glycosylation of the less reactive tertiary C - 20 - hydroxyl group in order to synthesize the $20-O-{\beta}-D-glucopyranoside$ of 20(S)-protopanaxadiol(=compound K) using 3, 12 - di - O - acetyldammar - 24 - ene - $3{\beta},12{\beta},20(S)$-trial as aglycon was unsuccessful. Glycosylation of 3, 12 - diketone of betulafolienetriol followed by $NaBH_4$ reduction yielded the $20-O-{\beta}-D-glucopyranoside\;of\;dammar-24-ene-3{\beta},12{\alpha},$ 20(S)-triol, the $12{\alpha}-epimer$ of 20(S) - protopanaxadiol. Moreover, a number of semisynthetic ocotillol - type glucosides, analogs of natural pseudoginsenosides, have been prepared.

• Mass Spectrometry Letters
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• v.6 no.3
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• pp.53-58
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• 2015

Recombinant erythropoietins (EPOs) are an important class of biotherapeutics that stimulate red blood cell production. The quality, safety, and potency of EPO variants are determined largely by their glycosylation, which makes up nearly half their mass. Thus, detailed glycomic analyses are important to assess biotherapeutic quality and establish the equivalency of biosimilar EPOs now coming to market. High-resolution mass spectrometry (MS) has recently emerged as the premier tool for glycan analysis in EPOs. Using the accurate mass measurements provided by high-resolution MS, the compositions of even large, complex glycans can easily be determined. When combined with a nano-LC separation, differentiation of structural isomers also becomes a possibility. These components, together, provide a comprehensive picture of biotherapeutic glycosylation. In this review, we provide an overview of MS-based analytical platform for glycomic characterization of EPO biotherapeutics and biosimilars.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1791-1800
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• 2004

Angiotensin I, a model decapeptide, was glycosylated and partially hydrolyzed with HCl (6 N, 80 $^{\circ}C$, 4 h), aminopeptidase, and carboxypeptidase Y. A single peptide mass map obtained from truncated peptides in the partial acid hydrolysate of angiotensin and its glycosylation product mixture by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry enabled sequencing of angiotensin by a combinatorial procedure. MALDI-TOF and electrospray ionization (ESI) tandem mass spectrometric results indicate that both the N-terminal amino group of aspartic acid and the guanidinium group of the second residue arginine are glycosylated.