• Korean Journal of Environmental Biology
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• v.21 no.4
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• pp.358-365
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• 2003

A bacterial strain capable of producing a novel bioflocculant was isolated from a biofilm sample and identified as Bacillus megaterium G31. The highest biopolymer yield was achieved when the organism was cultivated in a medium containing acetate as the sole carbon source and ($NH_4)_2HPO_4$as the nitrogen source. In kaolin suspension, the flocculating activity was highest at 170 mg I$^{-1}$ and decreased at the higher bioflocculant concentrations. The crude bioflocculant produced by the organism was purified by ethanol precipitation and gel permeation chromatography. The FTIR spectrum of the purified bioflocculant revealed that the bioflocculant might be a heterogeneous polysaccharide composed of hexosamines and neutral sugars. The analysis of sugar components of the bioflocculant using high performance anion-exchange chromatography showed that the sugar constituents of the bioflocculant were glucosamine, fucose, galactosamine, galactose, glucose, mannose in approximate molar ratio of 4 : 1 : 6 : 3 : 8 : 19. Its flocculating activity was stimulated by various cations. The bioflocculant was thermo-stable and retained 64% of its original activity after heating at $100^{\circ}C$ for 50 min.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.863-868
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• 2004

Lectin activities and chemical characteristics of Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. originating from the porcine cecal mucosal layer were studied based on hemagglutination assay (HA) and hemagglutination inhibition assay (HIA). Although all the bacterial strains were able to agglutinate erythrocytes of porcine or rabbit origin, much higher HA titers were consistently observed for Lactobacillus spp. than for E. coli or for Bifidobacterium spp. A remarkable reduction in HA titers occurred by the treatment of E. coli and Lactobacillus spp. with protease or trypsin and of Bifidobacterium spp. with protease, trypsin or periodate. There were no significant effects on the HA titers of the three groups of bacteria after the treatment with lipase. Hemagglutination of E. coli was strongly inhibited by D (+)-mannose and D (+)-galactose; Lactobacillus spp. by $\alpha$-L-rhamnose and methyl-$\beta$-galactopyranoside; Bifidobacterium spp. by D (+)-alactose, $\alpha$-L-rhamnose, $\alpha$-L-fucose, L (+)-arabinose, D (+)-mannose, D (-)-fructose at a relatively low concentration (1.43 to 3.75 mg/ml). These results, combined with the enhanced HA activities of the three bacterial strains by modification of rabbit erythrocytes with neuraminidase and abolished HA activity of E. coli after treatment with $\beta$-galactosidase, indicate that it might be the glycoproteinous substances surrounding the surface of the bacterial cells that are responsible for the adhesions of these microorganisms by recognizing the specific receptors on the red blood cell.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.209-216
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• 2002

Bacillus sp. A56 was studied, because of its high flocculating activity. The flocculating substance produced by this strain was purified by ethanol precipitation, cetylpyridinium chloride (CPC) precipitation, and gel permeation chromatography (GPC). The FT-IR spectrum of the purified bioflocculant, designated as BF-56, showed typical characteristics of polysaccharides. The non-sugar substituents, and sugar components of BF-56 containing glucose, fucose, glucuronic acid, and galactose in an approximate molar ratio of 2.76:1.10:1:0.12, suggested that it was a novel bioflocculant with an estimated molecular mass of over $7{\times}10^3$ kDa. Rheological analysis of BF-56 revealed that it was a pseudoplastic that had higher apparent viscosity rate at dilute concentrations than those of zooglan. The solution of bioflocculant BF-56 exhibited non-Newtonian characteristics and it was compatible to high concentrations of salts such as KCl, NaCl, $CaCl_2,\;or\;FeCl_3.$ The present results suggested strong possibility of bioflocculant BF-56 to be fully applicable to industries such as wastewater treatment.

• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1092-1096
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• 2020

YjiC, a glycosyltransferase from Bacillus licheniformis, is a well-known versatile enzyme for glycosylation of diverse substrates. Although a number of O-glycosylated products have been produced using YjiC, no report has been updated for nucleophilic N-, S-, and C- glycosylation. Here, we report the additional functional capacity of YjiC for nucleophilic N- and S- glycosylation using a broad substrate spectrum including UDP-α-D-glucose, UDP-N-acetyl glucosamine, UDP-N-acetylgalactosamine, UDP-α-D-glucuronic acid, TDP-α-L-rhamnose, TDP-α-D-viosamine, and GDP-α-L-fucose as donor and various amine and thiol groups containing natural products as acceptor substrates. The results revealed YjiC as a promiscuous enzyme for conjugating diverse sugars at amine and thiol functional groups of small molecules applicable for generating glycofunctionalized chemical diversity libraries. The glycosylated products were analyzed using HPLC and LC/MS and compared with previous reports.

• Preventive Nutrition and Food Science
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• v.12 no.2
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• pp.65-73
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• 2007

Sargassum fulvellum, a marine brown alga, is a popular low priced edible plant in Korean markets. The polysaccharide fraction of the alga was separated and investigated for its radical scavenging activities and the results compared with those of commercial fucoidans (Fucus vesiculosus and Undaria pinnatifida), BHA and ${\alpha}$-tocopherol. The polysaccharide fraction of S. fulvellum showed a promising DPPH radical scavenging activity than did other fucoidans. Moreover, the sample exhibited a dose-dependent activity on hydrogen peroxide scavenging activity in the V79-4 cell line. Interestingly, all the tested polysaccharide counterparts were more potent NO. scavengers than were the commercial antioxidants, BHA and ${\alpha}$-tocopherol. The sulfated polysaccharide of S. fulvellum had an approximate molecular weight of 529 kDa and mainly consisted of fucose and galactose, and minor amounts of mannose, rhamnose and xylose.

• Biomedical Science Letters
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• v.16 no.4
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• pp.221-227
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• 2010

To elucidate the invasion mechanism of pathogenic Naegleria fowleri, especially a receptor-ligand recognition, we investigated the in vitro cytotoxicity of pathogenic N. fowleri and nonpathogenic N. gruberi to murine macrophages, RAW 264.7, by adding four kinds of saccharides, ${\alpha}$-fucose, ${\beta}$-galactose, ${\alpha}$-D-mannopyranoside (${\alpha}$-mannose) and xylose. There was not enough of a difference in the cytotoxicity of N. fowleri treated with 10 mM of each saccharide. In particular, the cytotoxicity of N. fowleri was highly inhibited by 100 mM ${\alpha}$-mannose, which was 62.3% inhibition calculated by the analysis of lactate dehydrogenase (LDH) release assay. Although murine macrophages were not significantly destroyed by nonpathogenic N. gruberi under hematoxylin staining, the cytotoxicity of N. gruberi was inhibited from 31.5% to 14.5% (P<0.01) by 100 mM ${\alpha}$-mannose treatment. The binding of N. fowleri to macrophages was inhibited from 33% to 50% by 100 mM ${\alpha}$-mannose. Furthermore, as results of the adhesion assays which were performed to determine whether binding of Naegleria is mediated by saccharides-binding protein, the binding ability of N. fowleri as well as N. gruberi was inhibited by 100 mM ${\alpha}$-mannose.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1569-1573
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• 2012

Luteolin (LUT), a bioflavonoid has been used as a chemopreventive agent world-wide against chemically induced cancer. Hence we designed an experiment to assess chemopreventive action of LUT on lipid peroxidation (LPO) and glycoconjugates in azoxymethane (AOM)-induced colon carcinogenesis. Colon cancer was induced by 15 mg/body kg. body weight of AOM and administration of LUT (at the dose of 1.2 mg/kg. body weight) was till end of the study. Analysis of lipid peroxidative end products such as protein carbonyl (PC), malonadehyde (MDA) and conjucated dienes (CD) demonstrated significant increase in in AOM-induced animals with reduction by LUT (p<0.05). Increased levels of glycoconjugates such as hexose, hexosamine, sialic acid, fucose and mucoprotein were analyzed in serum and colon tissues examined histopathologically by periodic acid Schiff's (PAS) staining were also reversed by LUT l(p<0.05). The secondary marker of colon cancer mucin depleted foci (MDF) was assessed in control and experimental group of animals. A characteristic increase of MDF was observed in AOM-induced colon cancer animals. Treatment with LUT decreased the incidence of MDF. These results suggest that LUT alters the expression of glycoconjugates and suppress colon cancer. Hence, we speculate that LUT can be used as a chemopreventive agent to treat colon cancer.

• YAKHAK HOEJI
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• v.54 no.6
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• pp.449-454
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• 2010

The glycosylation of glycoproteins from mammalian or plants can affect their efficacy, stability, solubility, and half-life. In the present study, we investigated plant glycosylation and their relative intensity (%) in a plant carbohydratebinding protein with the hemagglutination and antiproliferative activities. The hemagglutination activity on the deglycosylated protein was decreased as a 16-fold than that of intact glycoprotein. Using the HPLC with fluorescence detector and mass spectrometer, the major eight bi- or triantennary oligosaccharides containing xylose, fucose, mannose, galactose, and N-acetylglucosamine were identified and structurally characterized. The present results indicate that the oligosaccharides on this plant glycoprotein is necessary for their own property.

• Natural Product Sciences
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• v.4 no.2
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• pp.62-67
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• 1998

As a part of search for new biologically active constituents from aloe, we have isolated a glycopeptide, called G1G1M1DI2, from the gel(G1) of Aloe vera. Chemical and spectroscopic evidence indicated that G1G1M1DI2 is a glycopeptide. The molecular weight of G1G1M1DI2 was about 5,500 daltons, and the carbohydrate and protein contents were 20.9% and 32.6%, respectively. Periodate oxidation and enzymic degradation gave peptide moiety and carbohydrate moiety, respectively. Carbohydrate moiety is composed of fucose, galactose, glucose and mannose in a molar ratio of 0.5:2.4;48.8:48.3. Peptide moiety is composed of fifteen amino acids, and glutamic acid and glycine were the major componants. The glycopeptide, G1G1M1DI2, stimulated thymidine uptake of SCC 13 cells about 6.5 times the control. This result suggests that this glycopeptide has a skin cell proliferating activity.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.631-640
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• 2011

Milk oligosaccharides are the complex mixture of six monosaccharides namely, D-glucose, D-galactose, N-acetyl-glucosamine, N-acetyl-galactosamine, L-fucose, and N-acetyl-neuraminic acid. The mixture is categorized as neutral and acidic classes. Previously, 25 oligosaccharides in bovine milk and 115 oligosaccharides in human milk have been characterized. Because human intestine lacks the enzyme to hydrolyze the oligosaccharide structures, these substances can reach the colon without degradation and are known to have many health beneficial functions. It has been shown that this fraction of carbohydrate can increase the bifidobacterial population in the intestine and colon, resulting in a significant reduction of pathogenic bacteria. The role of milk oligosaccharides as a barrier against pathogens binding to the cell surface has recently been demonstrated. Milk oligosaccharides have the potential to produce immuno-modulation effects. It is also well known that oligosaccharides in milk have a significant influence on intestinal mineral absorption and in the formation of the brain and central nervous system. Due to its structural resemblance, bovine milk is considered to be the most potential source of oligosaccharides to produce the same effect of oligosaccharides present in human milk. This review describes the characteristics and potential health benefits of milk oligosaccharides as well as the prospects of oligosaccharides in bovine milk for use in functional foods.