• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1347-1353
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• 2005

Sets of sialic acid-containing trisaccharides having different internal and terminal linkages have been synthesized to develop a sensitive method for analysis of the reducing terminal linkage positions. The trisaccharides, sialyl($\alpha$ 2-3)Gal($\beta$ 1-3)GalNAc and sialyl($\alpha$ 2-3)Gal($\beta$ 1-X)GlcNAc where X=3, 4 and 6, were synthesized and examined using electrospray ionization (ESI)-collision induced dissociation (CID) tandem mass spectrometry (MS/MS). The compounds chosen for this study are related to terminal groups likely to be found on polylactosamine-like glycoproteins and glycolipids which occur on the surface of mammalian cells. The purpose of this study is to develop tandem mass spectrometral methods to determine detailed carbohydrate structures on permethylated or partially methylated oligosaccharides for future applications on biologically active glycoconjugates and to exploit a faster method of synthesizing a series of structural isomeric oligosaccharides to be used for further mass spectrometry and instrumental analysis.

• Toxicological Research
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• v.34 no.3
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• pp.259-266
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• 2018

Glycomacropeptide (GMP), a whey protein of milk, has functions including differentiation and development of nervous system, and anticancer and antiviral effects. To develop new functions, N-acetylneuraminic acid (NANA) containing 7% sialic acid was separated from GMP to produce G-7%NANA. N-glycolylneuraminic acid (Neu5Gc) is another type of sialic acid separated from GMP, which has been linked to immune disorders and chronic inflammation-mediated diseases. Therefore, safety was a concern in the use of G-7%NANA in functional foods. To ensure safety, in this study, three genetic toxicity tests on G-7%NANA were conducted. In the reverse mutation test using Salmonella typhimurium TA98, TA100, TA1535, TA1537, and Escherichia coli WP2uvrA, and in the chromosome aberration test using CHO-K1 cells, no significant differences from negative control were found at all dose levels. Similarly, no dose-related differences were evident compared to negative control in the micronucleus test using ICR mice. There was no evidence of G-7%NANA-related genetic toxicity.

• Korean Journal of Veterinary Research
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• v.32 no.4
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• pp.463-479
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• 1992

The morphological findings of the parotid, mandibualr and sublingual salivary glands of the Korean native goat have been investigated by the histological and histochemical observation using the light microscope. Tissues were fixed with 10% neutral buffered formalin and Bouin's solution, and embedded in paraffin. The tissue sections were stained with hematoxylin and eosin, Heidenhain's azocarmine-aniline blue, alcian blue, toluidine blue, periodic acid Schiff, aldehyde fuchsin, alcian blue-periodic acid Schiff and aldehyde fuchsin-alcian blue. Some sections were stained with the alcian blue after each teatment of diastase digestion, methylation, methylation-saponification, and neuraminidase digestion. The results were as follows ; 1. The major salivary glands were compound. tubuloacinar glands, and the parenchyma was composed of acini, intercalated ducts, striated ducts and excretory ducts. 2. The acini were composed of serous cells in the parotid gland, and mucous cells, serous cells and seous demilunes in the mandibular gland. The acini of the sublingual glands were composed of mucous cells and serous demilunes. 3. In histochemistry, the serous cells of the parotid gland contained neutral mucin and enzyme-liable silaic acid. 4. The serous cells and demilunes of the mandibular gland contained neutral mucin and enzyme-liable sialic acid, and the mueous cells contained sulfated mucin, enzyme liable sialic acid and neutral mucin 5. In the sublingual gland, the mucous cells contained sulfated mucin, enzyme-resistant sialic acid and neutral mucin, and the serous demilunes contained neutral mucin and enzyme-resistant sialic acid.

• YAKHAK HOEJI
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• v.38 no.6
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• pp.800-805
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• 1994

Antacid(AM, 600 mg/kg=aluminium hydroxide, magnesium hydroxide, and simethicone with a ratio of 1 : 1 : 0.1) and aceglutamide aluminium(AGA, 263 mg/kg)-Effect of the combined preparation containing on the gastric mucosal hexosamine, sialic acid, and aluminium contents adhered to the gastric wall of the rat was investigated. Severe ulcers were produced in rats by injecting of $30\;{\mu}l$ acetic acid(30%) into the subserosal layer of one position in the corpus. When given orally for 15 consecutive days, AM(1,200 mg/kg), AGA(525, 1,050 mg/kg), and the combined preparation significantly decreased the ulcer area. AGA(525, 1,050 mg/kg) and the combined preparation also increased the amount of hexosamine and sialic acid in the intact and ulcerated areas. On the other hand, the contents of hexosamine and sialic acid were not affected by AM (600, 1,200 mg/kg). The amount of aluminium adhered to the gastric wall of the rat was higher in the combined preparation when compared to the AM(600 mg/kg) and AGA(263 mg/kg). The aluminium contents adhered may play an important role protecting mucosa from aggresive action of gastric juice and potenting defensive factors through the increase of mucosa-forming components by AGA.

• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.166-182
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• 2022

Deer antler velvet is widely used in traditional medicine for its anti-aging, antioxidant, and immunity-enhancing effects. However, few studies have reported on the discovery of probiotic strains for deer antler fermentation to increase functional ingredient absorption. This study evaluated the ability of probiotic lactic acid bacteria to enhance the concentrations of bioactive molecules (e.g., sialic acid and gamma-aminobutyric acid [GABA]) in extracts of deer antler velvet. Seventeen strains of Lactobacillus spp. that were isolated from kimchi and infant feces, including L. sakei, L. rhamnosus, L. brevis, and L. plantarum, and those that improved the life span of Caenorhabditis elegans were selected for evaluation. Of the 17 strains, 2 (L. rhamnosus LFR20-004 and L. sakei LFR20-007) were selected based on data showing that these strains increased both the sialic acid and GABA contents of deer antler extract after fermentation for 2 d and significantly improved the life span of C. elegans. Co-fermentation with both strains further increased the concentrations of sialic acid, GABA, and metabolites such as short-chain fatty acids and amino acids. We evaluated the biological effects of the fermented antler velvet (FAV) on the antibacterial immune response in C. elegans by assessing worm survival after pathogen infection. The survival of the C. elegans conditioned with FAV for 24h was significantly higher compared with that of the control worm group fed only normal feed (non-pathogenic E. coli OP50) exposed to E. coli O157:H7, Salmonella typhi, and Listeria monocytogenes. To evaluate the protective effects of FAV on immune response, cyclophosphamide (Cy), an immune-suppressing agent was treated to in vitro and in vivo. We found that FAV significantly restored viability of mice splenocytes and immune promoting-related cytokines (interleukin [IL]-6, IL-10, inducible nitric oxide synthase [iNOS], interferon [IFN]-γ, and tumor necrosis factor [TNF]-α) were activated compared to non-fermented deer antlers. This finding indicated the protective effect of FAV against Cy-induced cell death and immunosuppressed mice. Taken together, our study suggests that immune-promoting antler velvet can be produced through fermentation using L. rhamnosus LFR20-004 and L. sakei LFR20-007.

• Molecules and Cells
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• v.24 no.3
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• pp.416-423
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• 2007

Alterations in the glycan chains of cell surface glycoconjugates are frequently involved biological processes such as cell-cell interaction, cell migration, differentiation and development. Cultured embryonic (E18) rat cortical neurons underwent apoptosis in response to camptothecin, and lectin histochemistry showed that binding to apoptotic neurons of FITC-conjugated Maackia amurensis agglutinin (MAA), which is specific for terminal ${\alpha}2,3$-sialic acid residues, increased progressively with increasing concentrations of camptothecin. Analysis of the total proteins of apoptotic neurons by SDS-PAGE, and lectin blotting using HRP-labeled MAA, revealed that the expression of terminal ${\alpha}2,3$-sialic acid residues on an unknown protein with an apparent molecular mass of 25.6 kDa also increased in apoptotic neurons. NP-HPLC analysis of the total cellular N-glycans of normal and apoptotic neurons demonstrated that the expression of structurally simpler biantennary types of N-glycans fell by 49% during apoptosis whereas the more branched triantennary types of N-glycans with terminal sialic acid residues increased by up to 59%. These results suggest that increased surface expression of ${\alpha}2,3$-sialic acid residues and hyperglycosylation of N-glycans is a common feature of cellular responses to changes in cell physiology such as tumorigenesis and apoptosis.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.383-391
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• 2008

The glycans linked to the insect cell-derived glycoproteins are known to differ from those expressed in mammalian cells, partly because of the low level or lack of glycosyltransferase activities. GnT II, GnT IV, GnT V, and ST3Gal IV, which play important roles in the synthesis of tetraantennarytype complex glycan structures in mammalian cells, were overexpressed in Trichoplusia ni cells by using a baculovirus expression vector. The glycosyltransferases, expressed as a fusion form with the IgG-binding domain, were secreted into the culture media and purified using IgG sepharose resin. The enzyme assay, performed using a pyridylaminated-sugar chain as an acceptor, indicated that the purified glycosyltransferases retained their enzyme activities. Human erythropoietin expressed in T. ni cells (rhEPO) was subjected to in vitro glycosylation by using recombinant glycosyltransferases and was converted into complex-type glycan with terminal sialic acid. The presence of Nacetylglucosamine, galactose, and sialic acid on the rhEPO moiety was detected by a lectin blot analysis, and the addition of galactose and sialic acid to rhEPO was confirmed by autoradiography using $UDP-^{14}C-Gal\;and\;CMP-^{14}C-Sia$ as donors. The in vitro glycosylated rhEPO was injected into mice, and the number of reticulocytes among the ed blood cells was counted using FACS. A significant increase in the number of reticulocytes was not observed in the mice injected with in vitro glycosylated rhEPO as compared with those injected with rhEPO.

• KSBB Journal
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• v.31 no.4
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• pp.270-276
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• 2016

In glycoprotein, Terminal sialic acid residues of N-linked glycan are imperative things because they prevent the recognition from asialoglycoprotein-receptor that affect the half-life of glycoproteins. So establishment of culture process for enhancing sialic acid is important to maximize sialic acid contents of glycoprotein. In this study, we investigated effects of biphasic culture of Chinese hamster ovary (CHO) cells producing albumin-erythropoietin to increase sialylation. Biphasic cultures were performed with shift of $CO_2$ concentrations and temperatures at day 5 when viable cell density was decreased and sialidase was started to be released by cell lysis. The examined temperature set points were 33, 35 and $37^{\circ}C$ respectively and the $CO_2$ concentration was 1, 5, 10 and 15%. We confirmed that sialidase activity was the lowest in biphasic culture that was shifted from normal culture condition to 1% of $CO_2$ and $33^{\circ}C$ on day 5. However, the temperature and concentration of $CO_2$ have little effect on activity of ${\alpha}2,3$-sialyltransferase. Also, sialic acid contents were enhanced 1.13-fold higher than that in control culture. In conclusion, Biphasic cultivation in CHO cells led to inhibition of sialidase activity and increases of sialylated glycan.

• Korean Journal of Bronchoesophagology
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• v.10 no.1 s.19
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• pp.35-40
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• 2004

Adhesion molecules have been implicated in tumor progression. In this study, we aimed to investigate serum soluble intercellular adhesion molecule-1 (ICAM-1) and sialic acid (SA) levels in oral cavity cancer and laryngeal cancer and correlate their levels with cancer progression. Method : The sera from 31 patients with advanced oral cavity cancer (5 at stage III, 10 at stage IV) and advanced laryngeal cancer (1 at stage III, 15 at stage IV) were extracted before treatment. The concentrations of ICAM-1 was measured by Endogen kit (measured absorbance at 490nm) and the concentration of SA was measured by Roche kit (measured absorbance at 550nm). Respectively, gained data was compared with those from a control group (n=12). Result : Mean serum ICAM-1 and SA levels were found to be higher in oral cavity cancer group and laryngeal cancer group than control group. But statistical meaning was at SA (p<0.001, oral cavity cancer and laryngeal cancer versus control). Conclusion : These data reveal that the significant correlations serum SA level in advanced oral cavity cancer and laryngeal cancer. Serum ICAM-1 level was higher at advanced oral cavity cancer and laryngeal cancer than at control group but that was not significant.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.349-355
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• 2011

Russian deer velvet antlers were divided into three parts and subjected to a extraction process using hot water at 100, 110, and $120^{\circ}C$ or an extraction with 70% ethanol. Each extract was analyzed for its biochemical components, including uronic acid, sulfated-glycosaminoglycans (sulfated-GAGs), and sialic acid, and the antioxidant and anti-acetylcholinesterase activities were investigated. Different levels of uronic acid and sulfated-GAGs were observed in the extracts according to the water temperature used for the extraction, and contents decreased with increasing extraction temperature. The upper layer of each extract showed high amounts of uronic acid and sulfated-GAGs, followed by the middle and base layers. Ethanol extraction was more effective for recovering uronic acid than sulfated-GAGs. Sialic acid content was the highest in the $110^{\circ}C$ extracts but was not observed in the ethanol extracts. Velvet antler extracts showed strong antioxidant activities against DPPH and hydrogen peroxide as well as strong reducing power in a dose-dependent manner. However, the antioxidant activities were different in each layer and according to the extraction method. Additionally, velvet antler extracts exhibited inhibitory activity against acetylcholinesterase, which is associated with Alzheimer's disease, in a dose-dependent manner. These results suggest that velvet antler extracts are useful as a functional food ingredient and/or a pharmaceutical.