• 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.

• Preventive Nutrition and Food Science
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• v.20 no.2
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• pp.110-118
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• 2015

This study was performed to investigate changes in the content and purity, as well as physical characteristics of ${\beta}$-glucan extracted from acid hydrolyzed whole grain barleys. Waxy and non-waxy barleys (Hordeum vulgare) were hydrolyzed with different concentrations of HCl (0.1~0.5 N) for 1 h. As the HCl concentration increased, the contents of total and soluble ${\beta}$-glucan from acid hydrolyzed barley decreased. However the ratio of soluble/total ${\beta}$-glucan content and purities of ${\beta}$-glucan significantly increased. The ratio of ${\beta}-(1{\rightarrow}4)/{\beta}-(1{\rightarrow}3)$ linkages, molecular weight, and viscosity of soluble ${\beta}$-glucan of raw barleys were 2.28~2.52, $6.0{\sim}7.0{\times}10^5g/mol$, and 12.8~32.8 centipoise (cP). Those of isolated soluble ${\beta}$-glucan were significantly decreased to 2.05~2.15, $6.6{\sim}7.8{\times}10^3g/mol$, and 3.6~4.2 cP, respectively, with increasing acid concentration. The re-solubility of raw barley ${\beta}$-glucan was about 50%, but increased to 97% with increasing acid concentration. Acid hydrolysis was shown to be an effective method to produce ${\beta}$-glucan with high ratio of soluble ${\beta}$-glucan content, purity, water solubility, and low viscosity.

• The Korean Journal of Mycology
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• v.27 no.1 s.88
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• pp.76-81
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• 1999

Exo-polysaccharide obtained from the submerged cultivation of Ganoderma lucidum mycelium was fractionated. The structural analysis of the acidic exo-polysaccharide fraction (BWS-DA-GI), showing high antitumor activity, was carried out and compared to the mycelial acidic fraction (MWS-DA-GI). The major sugar constituents of the fraction of BWS-DA-GI were glucose, galactose and mannose in the molar ratio of 2.5 : 2.1 : 2.5. The minor components in this fraction were xylose and fucose. While the major sugar constituents of the mycelial acidic fraction of MWS-DA-GI were galactose, fucose, mannose and glucose. The trace components in this fraction was xylose. From the results of periodate oxidation, Smith degradation, affinity chromatography and methylation analysis, the chemical structures of the two fractions, BWS-DA-GI and MWS-DA-GI were both determined as ${\beta}-1,3$ glucans. It was also estimated that BWS-DA-GI had a $1{\rightarrow}6$ glucosidic linkage and MWS DA-GI had $1{\rightarrow}4$ and $1{\rightarrow}6$ glucosidic linkages. The molecular weights of these fractions, MWS-DA-GI and MWSDA-GI were estimated as $1.2{\times}10^6\;and\;1.0{\times}10^6$ dalton, respectively.