• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.166-173
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• 2006

Soyasaponins are phytochemicals of major interest fur their health benefits. Chemical investigation of a soybean phytochemical concentrate resulted in the isolation and identification of triterpenoid saponins. The MeOH extraction of defatted hypocotyl separated from soybeans was peformed by the automated solvent extractor (ASE). Fractionation was performed on a flash column ($150mm{\times}40mm$ i.d.) packed with a preparative $C_{18}$ reverse phase bulk packing material $(125\AA,\;55-105{\mu}m)$ and monitored at 210 nm, and collected 14 fractions. Consequent Fsat preparative column liquid chromatography (Fast PCLC) was performed for the purification of Fraction-I (Fr-I) collected from the fraction 8 and 9 of flash chromatography. Fsat PCLC was performed on a Luna $C_{18}\;10{\mu}m,\;100{\AA}$, semipreparative reverse phase column ($250cm{\times}50mm$ i.d.) for the purification of isolated unknown compound (Fr-I-2). Chemical structure of acetyl soyasaponin $A_1\;(MW:1436.6,\;C_{67}H_{104}O_{33})$ was identified and determined by a combination of extensive NMR ($^1H-NMR$, 400 MHz; $^{13}C-NMR$, 100 MHz; DEPT), IR, UV, and ESI-MS analysis.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.25-33
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• 2000

This study was carried out to find the optimal isolation conditions of xylan from steam-exploded materials, such as rice straw(Oryza sativa), barley straw(Hordeum vulgare) and oak wood(Quercus mongolica), In the chemical composition, we found that the contents of water-extractives and ash of rice straw and barley straw were more than those of oak wood. Rice straw, barley straw and oak wood were steam-exploded at 20kgf/$cm^2$ for 3 minutes or 6 minutes. The content of lignin in three different steam-exploded materials was higher than that of non-treated materials. The crude xylan was extracted with hot water and 0.5% KOH solution from steam-exploded materials. In the sugar type of crude xylan extracted with hot water and 0.5% KOH solution, the oligomer content of crude xylan extracted with hot water was much more than that of crude xylan extracted with 0.5% KOH solution. The crude xylan was purified with 5% barium hydroxide Solution and ethanol precipitation procedure. The content of xylose of purified xylan was over 85%, but other sugar residues(arabinose, mannose, galactose and glucose) were not removed completely.

• Journal of Microbiology and Biotechnology
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• v.27 no.7
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• pp.1249-1256
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• 2017

In our search for new sources of bioactive secondary metabolites from Streptomyces sp., the ethyl acetate extracts from endophytic Streptomyces SUK 25 afforded five active diketopiperazine (DKP) compounds. The aim of this study was to characterize the bioactive compounds isolated from endophytic Streptomyces SUK 25 and evaluate their bioactivity against multiple drug resistance (MDR) bacteria such as Enterococcus raffinosus, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter spp., and their cytotoxic activities against the human hepatoma (HepaRG) cell line. The production of secondary metabolites by this strain was optimized through Thornton's medium. Isolation, purification, and identification of the bioactive compounds were carried out using high-performance liquid chromatography, high-resolution mass liquid chromatography-mass spectrometry, Fourier transform infrared spectroscopy, and nuclear magnetic resonance, and cryopreserved HepaRG cells were selected to test the cytotoxicity. The results showed that endophytic Streptomyces SUK 25 produces four active DKP compounds and an acetamide derivative, which were elucidated as $cyclo-({\text\tiny{L}}-Val-{\text\tiny{L}}-Pro)$, $cyclo-({\text\tiny{L}}-Leu-{\text\tiny{L}}-Pro)$, $cyclo-({\text\tiny{L}}-Phe-{\text\tiny{L}}-Pro)$, $cyclo-({\text\tiny{L}}-Val-{\text\tiny{L}}-Phe)$, and N-(7-hydroxy-6-methyl-octyl)-acetamide. These active compounds exhibited activity against methicillin-resistant S. aureus ATCC 43300 and Enterococcus raffinosus, with low toxicity against human hepatoma HepaRG cells. Endophytic Streptomyces SUK 25 has the ability to produce DKP derivatives biologically active against some MDR bacteria with relatively low toxicity against HepaRG cells line.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.24-32
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• 1977

According to the chlorous salt method, most of holocellulose whose lignin was removed, was obtained. In extracting xylan from holocellulose by the different densities of alkali, 5% KOH was extracted three times but still there remained part of xylan in it and another composite of hemicellulose and cellulose was obtained. The extraction of 10% and 20% KOH showed a desirable result. Rather than the ordinary method to use a large quantity of ethanol in the precipitation isolation of xylan, the method to use a small quantity of ethanol in adopting the dialysis with cellophane-membrane by condensing density to one tenth, made il possible to extract a high purity xylan in a high retrieving rate. In isolating glucomannan, the residue of 5% KOH extraction contained a large quantity of xylan, the residue of 10% and 24% KOH extraction, also showed the same result and the comparison between glucose and mannose was approximately 1 : 1. The purification of Fehling solution made it possible to obtain comparatively pure xylan but the process of oxidation dissolution was complicated and the retrieving rate was low. This was not a good method. The ethanol titration purified a high purity xylan in a high retrieving rate and was a very excellent purifying method, considering its simple and easy process. These two purifying methods, however, could not completely remove the residue of arabinose. This will be examined and reported later.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.571-575
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• 2004

Escherichia coli O157:H7 cause hemorrhagic colitis and the extraintestinal complication of hemolytic-uremic syndrome, with their higher incidence occurring in children. Lipopolysaccharide (LPS) of E. coli O157:H7 is very important to make IgG anti-LPS with bactericidal activity. To identify the characteristic of E. coli OI57:H7, we isolated 60 MDa plasmid and amplified stx genes of shiga-like toxin (Stx) 1, 2 of E. coli O157:H7 by polymerase chain reaction (PCR) method. Using the simple purification method which contained phenol extract, ethanol precipitation and gel filtration steps, the LPS of E. coli O157:H7 was isolated and purified. Finally, we confirmed the purity of LPS through SDS-PAGE and silver nitrate staining.

• Journal of Life Science
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• v.20 no.12
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• pp.1801-1806
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• 2010

A $\beta$-xylosidase encoding gene from Klebsiella sp. Sc was cloned in Escherichia coli. The $\beta$-xylosidase gene consisted of an open reading frame of 1,680 nucleotides and encodes 559 amino acids with a deduced molecular weight of 63 kDa. The deduced amino acid sequence of the $\beta$-xylosidase from Klebsiella sp. Sc exhibits 90% identities and 95% positives compared to those from Klebsiella oxytoca (KOX), Lactobacillus lactis (LAC, 82%, 90%), Bacillus longum (BLON, 69%, 81%) and Escherichia coli (ECOLI, 47%, 63%). The $\beta$-xylosidase was purified by GST-fusion purification system. The pH and temperature optima of the enzyme were 6.6 and $55^{\circ}C$, respectively. The $\beta$-xylosidase hydrolyzes xylobiose to xylose.

• Biomedical Science Letters
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• v.16 no.3
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• pp.201-206
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• 2010

In order to develop procedures for the rapid isolation of recombinant sugar transporter in functional form from away from the endogenous insect cell transporter, gene fusion techniques were exploited. Briefly, BamH1-digested human HepG2 type glucose transport protein cDNA was first cloned into a transfer vector pBlueBacHis, containing a tract of six histidine residues. Recombinant baculoviruses including the human cDNA were then generated by allelic exchange following transfection of insect cells with wild-type BaculoGold virus DNA and the recombinant transfer vector. Plaque assay was then performed to obtain and purify recombinant viruses expressing the human transport protein. All the cell samples that had been infected with viruses from the several blue plaques exhibited a positive reaction in the immnuassay, demonstrating expression of the glucose transport protein. In contrast, no color development in the immunoassay was observed for cells infected with the wild-type virus or no virus. Immunoblot analysis showed that a major immunoreactive band of apparent Mr 43,000~44,000 was evident in the lysate from cells infected with the recombinant baculovirus. Following expression of the recombinant fusion protein with the metal-binding domain and enterokinase cleavage site, the fusion protein was recovered by competition with imidizole using immobilized metal charged resin. The leader peptide was then removed from the fusion protein by cleavage with porcine enterokinase. Final separation of the recombinant protein of the interest was achieved by passage over $Ni^{2+}$-charged resin under binding conditions. The expressed transport protein bound cytochalasin B and demonstrated a functional similarity to its human counterpart.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1021-1025
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• 2011

A Bacillus subtilis strain was isolated from the intestine of Sebastiscus marmoratus (scorpion fish) that was identified as Bacillus subtilis CH2 by morphological, biochemical, and genetic analyses. The chitosanase of Bacillus subtilis CH2 was best induced by fructose and not induced with chitosan, unlike other chitosanases. The strain was incubated in LB broth, and the chitosanase secreted into the medium was concentrated with ammonium sulfate precipitation and purified by gel permeation chromatography. The molecular mass of the purified chitosanase was detected as 29 kDa. The optimum pH and temperature of the purified chitosanase were 5.5 and $60^{\circ}C$, respectively. The purified chitosanase was continuously thermostable at $40^{\circ}C$. The specific acitivity of the purified chitosanase was 161 units/mg. The N-terminal amino acid sequence was analyzed for future study.

• KSBB Journal
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• v.14 no.6
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• pp.677-681
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• 1999

Purificationi of egg yolk immunoglobulin(IgY) was performed to understand the property of egg immunoglobulin. IgY differs from mammalian IgY in the molecular size(larger), isoelectric point(more acidic), and binding ability with mammalian complement and protein A(nonbinding ability). IgY is also known as ${\gamma}$-livetin and exists in egg yolk together with other two water-solubel proteins, ${\alpha}$-livetin(chicken serum albumin) and ${\beta}$-livetin(${\alpha}_2$-glycoprotein) and various lipoproteins(Low density lipoprotein, LDL and High density lipoprotein, HDL) which are the major components of egg yolk. The first step of isolation of IgY is to separate the water-solube proteins from lipoproteins. We report a simple method for separation of water soluble proteins using k-carrageenan and sedimentation. k-carrageenan was found to be effective for removal of yolk lipoprotein as a precipitate. IgY remained supernatant, and was isolated by chromatography on columns of DEAE-Sephacel and G 75 gel filtration chromatography.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.547-552
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• 2013

Cortex Phellodendri (CP) is derived from the dried bark of Phellodendron amurense. It has been widely used as a drug in traditional Korea medicine for treating diarrhea, jaundice, swelling pains in the knees and feet, urinary tract infections and infections of the body surface. In this study, preparative centrifugal partition chromatography (CPC) was successfully carried out to separate antibacterial compounds from a CP methanol extract. The optimum two-phase CPC solvent system was composed of n-butanol: acetic acid: water (4:1:5 v/v/v). The flow rate of the mobile phase was 3 $m{\ell}/min$ in ascending mode with rotation at 1,000 rpm. The CPC-separated fraction and purification procedures were carried out by preparatory HPLC. Palmatine weas identified by $^1H$, $^{13}C$-nuclear magnetic resonance and electrospray ionization-mass spectroscopy spectral data analysis.