• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.484-489
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• 1998

Galactooligosaccharides (GalOS) were efficiently produced by partially purified $\beta$-galactosidase from the yeast strain Bullera singularis ATCC 24193. Ammonium sulfate precipitation and ultrafiltration methods were used to prepare the enzyme. The enzyme activity decreased at $50^{\circ}C$ and above. A maximum yield of 40% (w/w) GalOS, corresponding to 120 g of GalOS per liter, was obtained from 300 g per liter of lactose solution at $45^{\circ}C$, pH 3.7 when the lactose conversion was 70%. The yield of GalOS did not increase with increasing initial lactose concentration but the total amounts of GalOS did. Volumetric productivity was 4.8 g of GalOS per liter per hour. During this reaction, the by-products, glucose and galactose, were found to inhibit GalOS formation. Reaction products were found to be comprised of disaccharides and trisaccharides according to TLC and HPLC analyses. We propose the structure of the major product, a trisaccharide, to be ο-$\beta$-D-galactopyranosyl-(l-4)-ο-$\beta$-D-galactopyranosyl-(l-4)-$\beta$-D-glucose (4'-galactosyl lactose).

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.243-248
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• 1999

Sialic acids are key determinants for biological processes, such as cell-cell interaction and differentiation. Sialyltransferases contribute to the diversity in carbohydrate structure through their attachment of sialic acid in various terminal positions on glycolipid and glycoprotein (N-linked and O-linked) carbohydrate groups. Gal$\beta$ 1,3(4)GlcNAc $\alpha$2,3-sialyltransferase (ST3Gal III) is involved in the biosynthesis of $sLe^{X}$ and sLe^{a}$ known as selection ligands and tumor-associated carbohydrate structures. The appearance and differential distribution of ST3Gal III mRNA during mice embryogenesis [embryonic (E) days; E9, E11, E13, E15] were investigated by in situ hybridization with digoxigenin-labeled RNA probes coupled with alkaline phosphatase detection. On E9, all tissues were positive for ST3Gal III mRNA expression whereas ST3Gal III mRNA on E11 was not detected throughout all tissues. On E13, ST3GAl III mRNA was expressed in different manner in various tissues. In this stage, ST3Gal III mRNA was positive only in the liver, pancreas and bladder. On E15, specific signal for ST3GAl III was detected in the liver, lung and forebrain. These results indicate that ST3Gal III is differently expressed at developmental stages of mice embryo, and this may be importantly related with regulation of organogenesis in mice.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.99-106
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• 2021

To circumvent the skin problem from phenylethanol (PhE), we have studied on the enzymatic synthesis of phenylethanol galactoside (PhE-gal) as an alternative to PhE. Base on the previous study, we optimized the reaction conditions for PhE-gal synthesis from PhE using E. coli β-galactosidase (β-gal). The optimal amount of β-gal, PhE concentration, pH, and temperature for PhE-gal synthesis were 0.45 U/ml, 1%, 8.0, 40℃, respectively. Under these conditions, about 81.9 mM PhE was converted into about 47.4 mM PhE-gal, in which the conversion yield was about 57.9%. Meanwhile, when the reaction mixture containing PhE and PhE-gal was mixed and fractionated with water-immiscible solvent (EA or MC), it was observed that PhE-gal was distributed in water phase, and PhE was distributed in solvent phase. Additionally, PhE-gal was clearly distributed into water phase when MC was used, but PE-gal was not when EA was used. In the future, we are planning to carried out the continuing study on developing an alternative cosmetic preservative using PhE-gal.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.954-961
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• 2017

We investigated the purifications of PE-gal and CPN-gal, synthesized by transgalactosylation reaction using recombinant ${\beta}$-gal. The reaction mixture containing PE and PE-gal was first mixed with EA, and thereafter PE and PE-gal were distributed in two-phase (EA/water) system. In this system, PE and PE-gal was selectively moved into EA and water phase, respectively. Then, the water phase was collected, and silica gel chromatography was carried out using the collected water phase. Finally, we compared two purified PE-gal samples using HPLC and TLC analysis, in which the one was purified only by silica gel chromatography and the other was purified by EA extraction followed by silica gel chromatography. In the latter case, the residual PE was almost completely removed, whereas, in the former case, the residual PE was remained remarkably. Additionally, the purification yield of PE-gal was about 21% on the basis of mole. In the same purification protocol, CPN-gal was able to be purified using EA extraction followed by silica gel chromatography, in which the residual CPN was almost removed when CPN-gal was purified by EA extraction followed by silica gel chromatography.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.405-411
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• 2007

Gal-13 is an antimicrobial peptide isolated from chicken intestine. Ninety chickens were randomly divided into two groups (45 chickens for each group) to determine the effect of oral administration of Gal-13 on the acquired immune response. The chickens in the first group were fed a diet without Gal-13 as the control, and the chickens in the second group were fed the same diet, except that Gal-13 ($1{\mu}g/ml$) was suspended in drinking water just after hatching. Samples of blood, thymus, bursa of fabricius and spleen were taken at day 1, 4, 7, 10 and 17. The chickens in both groups received infectious bursal disease virus vaccine at day 20, and then sera samples were collected for analysis at 14, 21, 28 and 35 days after vaccination. The results showed: (1) Gal-13 could enhance the content of immunoglobulin (Ig)G at the age of 4 to10 days (p<0.05) and IgM at the age of 4 and 10 days (p<0.05) in the serum; (2) In vitro experiments showed that Gal-13 (0.625-1.250${\mu}g/ml$) enhanced the proliferation of peripheral blood lymphocytes of the chickens stimulated by lipopolysaccharide (LPS) and concanavlin A (ConA). Compared to the control, Gal-13 (1 ${\mu}g/ml$) enhanced the proliferation of bursa lymphocytes at 17 days of age (p<0.01) and thymus lymphocytes at 7 days of age (p<0.01), but restrained lymphocyte proliferation in chicken spleen and differed significantly at day 10 (p<0.01); (3) Gal-13 enhanced infectious bursal disease virus antibody in sera of chickens 21 days after infectious bursal disease virus vaccine administration (p<0.05). These results suggested that Gal-13 could modulate adaptive immune responses of chickens.

• Journal of the Korean Applied Science and Technology
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• v.38 no.3
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• pp.824-831
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• 2021

1, 2-Octanediol galactoside (OD-gal) has been synthesized from 1, 2-octanediol (OD), as a safer cosmetic preservative, using recombinant Escherichia coli β-galactosidase (β-gal). To confirm the molecular structure of synthesized OD-gal, mass spectrometry and NMR (¹H- and ¹³C-) spectroscopy of OD-gal were carried out. In the reaction mixture, a sodium adduct ion of OD-gal (m/z=331.1732) was identified using mass spectrometry analysis. In addition, ¹H NMR spectrum of OD-gal showed multiple peaks corresponding to the galactosyl group, which is evidence of galactosylation on OD. Downfield proton peaks at δ_H 4.39 ppm and multiple peaks from δ_H 3.98~3.55 ppm were indicative of galactosylation on OD. Up field proton peaks at δ_H 1.52~1.26 ppm and 0.89 ppm showed the presence of CH₂ and CH₃ protons of OD. ¹³C NMR spectrum revealed the presence of 24 carbons suggestive of α- and β-anomers of OD-gal. Among 14 carbon peaks from each anomer, the 4 peaks at δ_C 31.4, 29.0, 22.3, and 13.7 ppm were assigned to be overlapped showing only 24 peaks out of a total of 28 peaks. The mass value from mass spectrometry analysis of OD-gal, and ¹H and ¹³C NMR spectral data were in good agreement with the expecting structure of OD-gal. Finally, we identified a galactose molecule from the hydrolysate of OD-gal using β-gal. We are expecting that through future study it will eventually be able to develop a safe cosmetic preservative.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.35-43
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• 1999

Hepatoprotective effects of Malloti cortex extract (MCE) from Mallotus japonicus against the carbon tetrachloride (CCl$_{4}$) and galactosamine (GalN) were investigated. Whereas serum aspartate aminotransferase and alanine aminotransferase levels were markedly elevated after CCl$_{4}$ and GalN administration, pretreatment and posttreatment with MCE before and after the injection of CCl$_{4}$ and GalN resulted in decreases in elevated serum aminotransferase activities. Whereas CCl$_{4}$ and GalN treatment caused 3~7 fold increases in sorbitol dehydrogenase and ${\gamma}$-glutamyltransferase activities, pretreatment and posttreatment with MCE resulted in the blocking of CCl$_{4}$ and GalN-induced liver toxicity. The hepatoprotective effect of MCE was in part due to MCE-induced elevation of hepatic glutathione levels. Pretreatment and posttreatment with MCE also reduced increased lipid peroxidation induced by CCl$_{4}$ and GalN. These results suggest that MCE may be useful for the prevention and therapy of hepatotoxic pathogenesis. It is presumed that protective and therapeutic effects of MCE due to be inducible glutathione S-transferase and glutathione reductase activities, involving in glutathione-medicated detoxication and maintainment of glutathione content, respectively.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.498-506
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• 2016

1, 2-Hexanediol galactoside (HD-gal) has been previously synthesized from 1, 2-hexanediol (HD), in which recombinant ${\beta}$-galactosidase (${\beta}$-gal) of Escherichia coli (E. coli) was used for transgalactosylation reaction. In this study, a method for HD-gal purification from the reaction mixture was particularly investigated. Using ${\beta}$-gal-containing E. coli, HD-gal was synthesized from 75 mM HD for 48 hr under 300 g/l lactose concentration. Then, HD-gal synthesis from HD was confirmed by TLC analysis, and the existence of E. coli ${\beta}$-gal during 48 hr-reaction was also confirmed by Western blotting, in which the conversion yield of HD to HD-gal reached about 94% during 48 hr. To establish an efficient method for HD-gal purification, we carried out the solvent extraction of the reaction mixture, followed by silica gel chromatography, particularly in order to remove the residual HD. Two water-immiscible solvents, such as methylene chloride and ethyl acetate, were investigated comparatively to find out appropriate solvent. Then, it was found that residual HD was almost removed when ethyl acetate extraction of water phase of reaction mixture was carried out four times. Subsequently, silica gel chromatography was carried out, and purified HD-gal could be finally obtained. The production yield for HD-gal from 75 mM HD was $8.9{\pm}0.6%$ (n=3) (mole basis) or $21.1{\pm}1.4%$ (n=3) (weight basis). For further study, using purified HD-gal, we will investigate the minimum inhibitory concentrations (MICs) of HD-gal against bacteria. In addition, cytotoxicity to human skin cells of HD-gal will be examined.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.379-383
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• 2004

For the elucidation of substrate specificity to the brown copra meal by Bacillus sp. ${\beta}-mannanase.$, the enzymatic hydrolysate after 24 hr of reaction was heated in a boiling water bath for 10 min, and then centrifuged to remove the insoluble materials from hydrolysates. The major hydrolysates composed of D.P 5 and 7 galactosyl mannooligosaccharides. For the separate of galactosyl mannooligosaccharides, the supernatant solution of 150 ml was put on a first activated carbon column. The column was then washed with 5 l of water to remove mannose and salts. The oligosaccharides in the column were eluted by a liner gradient of $0{\sim}30%$ ethanol, at the flow rate of 250 ml per hour. The sugar composition in each fraction tubes was examined by TLC and FACE analysis. The combined fraction from F3 was concentrated to 30 ml by vacuum evaporator. Then put on a second activated carbon column. The oligosaccharides in the column were eluted by a liner gradient of $0{\sim}30%$ ethanol (total volume: 5 l), at the flow rate of 250 ml per hour. The eluent was collected in 8 ml fraction tubes, and the total sugar concentration was measured by method of phenol-sulfuric acid. The major component of F2 separated by 2nd activated carbon column chromatography were identified $Gal^3Man_4(6^3-mono-{\alpha}-D-galactopyranosyl-{\beta}-mannotetraose)$. To investigate the effects of brown copra meal galactomannooligosaccharides on growth of Bifidobacterium longum, B. bifidum were cultivated individually on the modified-MRS medium containing carbon source such as $Gal^3Man_4$, compared to those of standard MRS medium.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.84-89
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• 2019

To characterize the molecular structure of BzO-gal synthesized using Escherichia coli ${\beta}$-gal, NMR ($^1H$- and $^{13}C$-) spectroscopy and mass spectrometry of BzO-gal were conducted. $^1H$ NMR spectrum of BzO-gal showed multiple peaks corresponding to the galactosyl group, which is an evidence of galactosylation on BzOH. Five proton peaks around the aromatic region at ${\delta}_H$ 7.43 ~ 7.24 ppm and 2 peaks from ${\delta}_H$ 4.93 and 4.67 ppm were evidence of the presence of the benzyl group. Seven proton peaks at ${\delta}_H$ 4.32 ~ 3.46 ppm showed the presence of a monosaccharide and were indicative of galactosylation on BzOH. $^{13}C$ NMR spectrum also revealed the presence of 11 carbons suggestive of BzO-gal. The mass value (sodium adduct ion of BzO-gal, m/z = 293.0994) from mass spectrometry analysis of BzO-gal, and $^1H$ and $^{13}C$ NMR spectral data were in good agreement with the expecting structure of BzO-gal. We are expecting that through future study it will eventually be able to develop a new additive of low cytotoxicity.