• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.776-782
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• 2005

The effects of purification using ${\alpha}-amlyase$ (Termamyl 120L) on physicochemical properties of ${\beta}-glucan$ from oat bran were studied. Four fractions were selected as fraction A ($55^{\circ}C$, 15%, pH 6), fraction B ($45^{\circ}C$, 15%, pH 6), fraction C ($50^{\circ}C$, 0%, pH 7), and fraction D ($50^{\circ}C$, 10%, pH 5) from the result of physiological test, and three consecutive subfractions were obtained by repeated ${\alpha}-amlyase$ treatments on the each fractions. The contents of ${\beta}-glucan$, protein, and ash after purification were in 81.4-88.2%, 4.1-6.3% and 2.6-6.2%, respectively. The apparent viscosities of purified ${\beta}-glucan$ aqueous solutions were similar to those of hydroxy methyl cellulose. Glucose was a major monosaccharide of ${\beta}-glucan$ extracts, and xylose and arabinose were also detected as minor constituents on TLC. The average molecular weight ranged $2.0{\times}10^6-5.1{\times}10^6$ and was decreased after purification. From the result of the differential scanning calorimetry, the melting point ranged $130-140^{\circ}C$ with purification step and thermal transition enthalpy was increased. The ratio of ${\beta}-(1{\rightarrow}3)\;to\;{\beta}-(1{\rightarrow}4) $ linkages were 1:2.22-1:2.52, and increased up to 1:5.50 after purification.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.15-21
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• 1993

Crude ${\beta}-glucan$ extracted from Barley was purified by stepwise enzyme treatment (Thermostable ${\alpha}-amylase$, amyloglucosidase, protease). The Intrinsic Viscosity $[{\eta}]$ of the purified ${\beta}-glucan$ was determined by Cannon Fenske Capillary Viscometer (size 50, Cannon Instruments, State, College pa.) at different pH (2, 4, 7, 9, 11) and various salt concentration (0.01 M, 0.03 M, 0.05 M, 0.07 M, 0.1 M and 0.2 M). The $[{\eta}]$ of purified ${\beta}-glucan$ was ranged from $0.997{\sim}2.290\;dl/g$. The $[{\eta}]$ of purified ${\beta}-glucan$ at both alkali, acid condition were lower than those at pH 7. However, the alkali condition of puified ${\beta}-glucan$ solution showed less $[{\eta}]$ than the acid condition of this solution. From 0 M to 0.2 M salt concentration, the $[{\eta}]$ of purified ${\beta}-glucan$ solution was decreased to 0.03 M then increased to 0.05 M NaCl and remained constant to 0.2 M NaCl. The chain stiffness parameter of purified ${\beta}-glucan$ was not affected by temperature from $15^{\circ}C$ to $65^{\circ}C$. The shear rates of various ${\beta}-glucan$ conditions were determined by Bohlin Rheometer (Lund, Sweden). The ${\beta}-glucan$ concentration of 1.0 g/dl and 2.0 g/dl behaved as Newtonian fluid. However, above the concentration of 3.0 g/dl ${\beta}-glucan$ solution, it showed thixotropic and psedoplastic characteristics. Barley ${\beta}-glucan$ appears a damping at 0.5 frequency for the 4.0 g/dl solution. Below 0.5 frequency, it appears a viscous behavior property and above 0.5 frequency, it appears a elastic behavior property.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.541-545
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• 2009

Water and ethanol extracts were prepared from the haesongi mushroom (Hypsizigus marmoreus) to measure functional components. The ability of the extracts to inhibit angiotensin-converting enzyme (ACE) and their hypoglycemic effects were also determined; the latter was measured by $\alpha$-amylase and glucosidase inhibition. Extraction yield, protein content, total phenol, and $\beta$-glucan in the water extracts were 55.86, 17.71, 1.89, and 21.93%, respectively. The respective values for the ethanol extracts were lower than those for water extracts. Both water and ethanol extracts showed dosedependent ACE inhibition, the effect of the former being greater. The water extract inhibited ACE activity by 95.34% at 40 mg/mL. The $IC_{50}$ values of the water extracts were 63.32 and 0.41 mg/mL for $\alpha$-amylase and glucosidase, respectively. Thus, the water extracts had a greater hypoglycemic effect than the ethanol extracts. From these results, water is a better solvent than ethanol to extract from the haesongi mushroom functional components that show ACE inhibition and have hypoglycemic effects.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.215-218
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• 2004

Dextrans make up a class of polysaccharides that are D-glucans of various structures with contiguous $\alpha$-1longrightarrow6 ~6 glycosidic linkages in the main chains and $\alpha$-1longrightarrow2, $\alpha$-1longrightarrow3, or $\alpha$-1longrightarrow4 branch glycosidic linkages, depending on the specificity of the particular dextransucrase. Glucansucrases that catalyze glucans synthesis from sucrose. When other carbohydrates, in addition to sucrose, are present in the enzyme digest, the enzyme transfers glucose to the carbohydrate acceptors in the secondary reaction that diverts some of the glucose from incorporation into glucan. Many carbohydrate acceptors have been recognized and the products that result are dependent on the particular enzyme and the structure of the particular acceptor. Because of these unique catalytic characteristics, various dextransucrases have many important industrial and medical uses. To improve the understanding of their action mode and extend their applications, this study describes mechanism of glucan synthesis and potential industrial uses of dextransucrases, and our recent findings on the structural, functional organization and directed evolution of the glucansucrases to offer for designing glucansucrases with improved properties.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.1-8
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• 2001

To examine the structural properties of the proteoglycan (GMPG, Ganoderma lucidum mycelial proteoglycan) obtained from mycelia in Ganoderma lucidum IY009, we obtained the low and high molecular proteoglycan by ultrafiltration and sepharose CL-4B column chromatography. The physicochemical properties of these fractions were as follows. When the proteoglycan separated by ultrafiltration and sepharose CL-4B column chromatography, its was not fractionated completely. The molecular weight of high molecular proteoglycan by the gel column chromatography (CH) was 250 kD and 2,000 kD, and low molecular proteoglycan was 12kD. The total carbohydrate was consisted of 75.7% (UH) and 96.7% (CH), and the low fraction was 72.7% (UL) and 87.1% (CL), respectively. The sugar of high and low molecular proteoglycan composed of glucose, mannose, fructose, galactose, xylose, ribose and arabinose. Glucose contents of all fraction were ranged from $46.9%{\sim}82.4%$ of the total sugar and the ratio of ${\alpha}$\;and\;{\beta}-glucose$ was $0.84{\sim}1.14$, and its indicated the proteoglycan to be ${\beta}-glucan$. Amino acids pattern showed that the fractions contained a large amount of aspartie acid, glutamic acid, alanine and leucine. These fractions showed the characteristics of IR absorption for ${\beta}-glucan$ at $890\;cm^{-1}\;and\;^{13}C-NMR$ spectroscopy showed the presence of the ${\beta}-1,3-glucan$ and a ${\beta}-1,6-glucan$.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.12 no.2
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• pp.108-112
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• 2012

Glycogen storage disease type III (GSD type III, OMIM #232400) is a rare autosomal recessive disease caused by a deficiency of the glycogen-debranching enzyme (GDE) with a mutation in the AGL gene (OMIM *610860). It is known to be bifunctional enzyme, that is, having two independent catalytic activities; 1,4-${\alpha}$-D-glucan 4-${\alpha}$-D-glycosyltransferase (EC 2.4.1.25) and amylo-1,6-glucosidase (EC 3.2.1.33) that occur at separate active sites on a single polypeptide chain. Most patients with GSD type III usually have symptoms related to decreased glycogenolysis in liver and muscles, such as hepatomegaly, hypoglycemia, failure to thrive, hyperlipidemia, muscle weakness and cardiomyopathy (type IIIa), however some patients show symptoms restricted to liver (type IIIb). GSD type III is diagnosed by enzyme test through liver or muscle biopsy or mutation analysis of the AGL gene. We report the case of GSD type III proven by gene study after liver biopsy, which revealed c.476delA, c.3444_3445insA in exon 6, 27 of AGL gene in Korean patient.

• KSBB Journal
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• v.14 no.3
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• pp.384-388
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• 1999

We have used high pH anion-exchange chromatography to analyze low level (below $20{\mu}M$) $\alpha$-D-glucose-1-phosphate (G-1-P) that can be used as a cytostatic compound, an antibiotic, and immunosuppressive drug. Our chromatographic method afforded excellent peak resolution and seletivity for glucose-6-phosphate and various maltooligosaccharides as well as G-1-P. The pulsed amperometric detector yielded linear response on G-1-P ranging from 2 - $20{\mu}M$, giving slope of $4.8{\times}10^4$(peak area/${\mu}M$). The detection limit was $2{\mu}M$. This method was applied to the purification of thermophilic $\alpha$-glucan phosphorylase from Thermus caldophilus. The technique will be extremely useful in future studies concerning carbohydrate metabolism in living organisms.

• The Korean Journal of Mycology
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• v.27 no.6 s.93
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• pp.424-429
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• 1999

This study was conducted to investigate the characteristics of polysaccharides isolated from the fruit body and cultured mycelia of Phellinus linteus IY001. All fractions were extracted by hot water, followed by ethanol precipitation (F-THE and M-HE) or ultrafiltration (M-HU) (F-TH, F-THE; fruit body, M-HE, M-HU; cultured mycelia). Among these fractions, F-TH fraction was obtained at the highest yields of 6.83% and yield of F-THE was at the level 2.79%. The carbohydrates of these fractions was found to be a heteroglucan composed of glucose, galactose, mannose, fructose, ribose and xylose by analysis of gas chromatography. The total carbohydrate contents of M-HE and M-HU fractions were 99.2%, and 86.0% respectively. The glucose content of M-HE, M-HU and F-THE ranged from 54 to 84.8% of the total monosaccharide. Amino acid pattern showed that all fractions contained a large amount of aspartic acid, glycine, glutamic acid, alanine. Serine and threonine were found to be involved in the linkage, O-linked type. These fractions, except F. TH, contained polysaccharides with the molecular weights of 12 kD and showed the characteristics of IR absorption for ${\beta}-glucosides$ at $890\;cm^{-1}$.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.504-510
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• 1988

The physicochemical properties of rice flours which were obtained by dry milling(blade, hammer, test and micro mill) and wet & dry milling (roller & micro mill) were investigated. The resulting flour particle sizes were reduced in the order that of blade, hammer, test, micro and roller & micro mill. Scanning electron microscopic examination showed that the starch granules were freed from the imbedding matrix as the particles became finer. The test-milled flour had the hightest levels of starch damage, maltose value and hot-water soluble amylose content, and the blade-milled flour showed the lowest levels. Amylograph viscosity and gelatinization temperature of the flours decreased as the particles became finer, and the addition of $Hg^{+2}$ increased the peak viscosity of the dry-milled flour pastes, whereas the wet & dry-milled flour did not show any changes. The blue values and ${\lambda}$max values of the iodine complex of the cold-water extractable ${\alpha}-D-glucan$ from flours were in the range of 0.023-0.029 and 518-522nm, respectively, indicating these materials were shown to be mainly composed of amylopectin-like polymer.

• KSBB Journal
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• v.19 no.2
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• pp.164-167
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• 2004

Cyclodextrin glucanotransferase (EC 2.4.1.19, abbreviated as CGTase) is one of the most applied industrial enzymes that produces cyclodextrins from starch and related ${\alpha}$-1,4-glucans by intramolecular transglycosylation reaction upon Ca$\^$2＋/ dependent manner. The reaction of CLEC, ${\alpha}$-CGTases from Bacillus macerans with the soluble starch as a substrate reveals that the surfactants (SDS, N-octyl-${\beta}$-D-glucoside) significantly affect not only the overall products of CDs but also their selectivity. The surfactants (SDS, Lubrol PX) trigger the increase of ${\alpha}$-CD production, but Triton x-100 and Tween 80 suppress ${\alpha}$-CD specificity. Organic solvents (dimethyl sulfoxide, formamide, 2-methyl-2,4-pentandiol, and ethylene glycol) also cause changes of total product and product selectivity.