• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.644-650
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• 1999

A normal and a waxy hull-less barley with similar ${\beta}-glucan$ contents were selected, and the effects of ${\beta}-glucans$ on rheological and pasting properties were investigated by using their flour extracts and isolated ${\beta}-glucan$ gum materials. ${\beta}-Glucans$ in the barley cultivars were extracted in a crude form with alkaline extraction, and the waxy hull-less barley produced more ${\beta}-glucan$ gum yield. The waxy barley also showed higher viscosities of water and alkaline flour extracts, compared to the normal barley. Both normal and waxy barley ${\beta}-glucan$ gums exhibited pseudoplastic flow behavior, and increasing ${\beta}-glucan$ concentration increased viscosity in a similar manner. The normal barley flour had a higher amylograph peak viscosity than did waxy barley flour. On the other hand, waxy barley flour with treatment of $HgCl_2$ demonstrated considerably higher increase in peak viscosity. Pasting characteristics of normal and waxy barley starches in the presence of ${\beta}-glucan$ gum solutions were tested using a rapid visco-analyzer (RVA). ${\beta}-Glucan$ gums increased the pasting viscosities of the barley starches, and the synergistic increase in viscosity appeared to be higher in the normal barley starch.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.616-623
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• 2003

Waxy barley brans were collected during the pearling process. The extraction of $\beta$-glucan from barley bran was effected by the extraction conditions. The $\beta$-glucan content increased with temperature, but not with pH. The highest yield, 6.5%, was achieved at pH 7.0 and 55$^{\circ}C$. At pH 10 and 45$^{\circ}C$, 48.5% of the $\beta$-glucan in barley bran was recovered in the gum product, with 54.6% purity. The protein and starch contaminations were high, reaching 13.6 and 23.7%, respectively. The $\beta$-glucan content was greatest in the subaleurone and aleurone regions (bran fractions 1, 2, 3 and 4), and declined considerably toward the inner layers. A monosaccharide analysis of the purified, $\beta$-glucan, from bran fractions 1, 2, 3 and 4, indicated that glucose constituted the majority of the gum. The small amounts of the arabinose and xylose found in the gum may indicate the presence of arabinoxylans as minor constituents. The molecular weights of the $\beta$-glucans isolated from bran fractions 1,2 and 3 were found to be 4.09${\times}$10$^{5}$ ∼-4.41${\times}$10$^{5}$ . The major glycosidic linkages of the $\beta$-glucans demonstrated the presence of 2, 4, 6-Me-Glc and 2, 3, 6-Me-Glc. When flow behaviors of barley bran $\beta$-glucan were examined, $\beta$-glucan exhibited pseudoplastic fluid properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.785-788
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• 1998

Oat gum, a soluble dietary fiber, was extracted from rolled oat and the content of $\beta$-glucan and the cholesterol adsorption activity of oat gum were examined. The content of oat gum extracted from rolled oat was 5.15% and the amount of $\beta$-glucan in the oat gum was 29.48%. Most of the cholesterol adsorption of oat gum occurred within 10 hours in the dialysis cell and the cholesterol adsorption activity of oat gum was between 12 to 25%.

• Food Science of Animal Resources
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• v.33 no.3
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• pp.363-368
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• 2013

The main attributes of yogurt that affect consumer satisfaction are taste, consistency, and a firm texture. This study evaluates the influence of xanthan gum, barley beta-glucan, and guar gum in concentrations of 0.05%, 0.1%, 0.2%, and 0.3% on probiotic yogurt. The set-type yogurt samples were prepared by using raw cow's milk. The statistical analysis showed that none of these gum additions had any marked effect on pH, titratable acidity, total solids content, and probiotic bacteria counts of yogurt samples. Evaluations for syneresis and water-holding capacity (WHC) in the yogurt samples were affected by the type and concentration of the stabilizer. Yogurts treated with 0.1% xanthan gum and 0.3% beta-glucan recorded the highest WHC and the least syneresis. The largest amount of gel firmness was recorded in yogurt samples treated with 0.2% xanthan gum and 0.3% beta-glucan. Yogurt samples treated with 0.1% xanthan gum and 0.3% beta-glucan were considered acceptable by trained panelists and gained the highest scores in sensory evaluations. The correlation coefficient between the amount of syneresis, WHC and stiffness of texture was significant compared to scores for sensory evaluation (p<0.01). Results for effects of guar gum on the tested parameters were contrary to the results expected from a gum. According to this study, the use of xanthan gum and beta-glucan are highly recommended for low-fat yogurt production.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.382-386
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• 1998

A soluble dietary fiber, $\beta$-glucan, contained in oat and barley has nutritional benefits such as hypocholesterolemic effects and influences blood glucose regulation. The contents of $\beta$-glucan in both cereals range from 3 to 7% with the exception of a certain barley genotype which contains up to 16% $\beta$-glucan. $\beta$-Glucan is distributed mainly in the cell walls of endosperm and the distal (bran) portion of kernel. Various procedures have been developed for increasing the extraction yield of $\beta$-glucan. Oat gum prepared with weak alkali extractionand alcohol proecipitation following protein removal usually contains 80% $\beta$-glucan.The most commonly used method for $\beta$-glucan quantitiation is an enzymatic procedure combining lichenase plus $\beta$-glucosidase followed by measuring the amount of glucos released by glucose oxidase-peroxidase treatment. The increase in foam-and emulsion-stabilizing capacity of $\beta$-glucan is due to the increase in viscosity of the aqueous phase. Therefore, $\beta$-glucan shows great potentials as a thickener and a stabilizer.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.900-903
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• 2009

An oat gum was extracted from whole seeds of a drought harvested oat (Avena sativa). Oat gum presented a ${\beta}-glucan$ content of 65%(w/w) and an intrinsic viscosity of 141 mL/g. Gelling capability of oat gum at different concentrations was investigated. Gel hardness increased from 0.08 to 0.25 N as the oat gum concentration changed from 5 to 10%(w/v). Whippability, foam stability, emulsion stability, and reduced viscosity of oat gum at different pH were also investigated. Oat gum whippability was maximum at pH 7 (146%), while the higher foam and emulsion stability values were found at pH 9 (88 and 96%, respectively). The gum reduced viscosity increased from 715 to 958 mL/g as the pH changed from 7 to 9. Oat gum shows great potential as a gel forming, thickening, and stabilizing agent.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.266-272
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• 1986

The contents of water soluble ${\beta}-glucan$ were $1.4{\sim}4.0%$ in grains of 4 recommended varieties, and $0.3{\sim}0.6%$ in their malt. The ${\beta}-glucan$ content was subject to environmental factors such as cultivating region and nitrogen fertilizer level. The ${\beta}-glucan$ content of grains was positively correlated with the viscosity, but negatively with the protein and total gum contents. The ${\beta}-glucanase$ activity was $11.0{\sim}20.0$ sec as the reduced flow time in malt of 4 recommended varieties and was also subject to environmental factors. ${\beta}-Glucanase$ activity showed the highest level after the 6th day during malting. The ${\beta}-glucanase$ activity in malt was positively correlated with malt extract, but negatively with the residual ${\beta}-glucan$ content. The protein content in malt was negatively correlated with malt extract, but positively with the diastatic power.

• Korean Journal of Microbiology
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• v.45 no.3
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• pp.257-262
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• 2009

Carboxymethyl celluase (cellulase) was purified from cell-free extract of the recombinant Escherichia coli carrying a Bacillus licheniformis WL-12 cellulase gene by DEAE-Sepharose and phenyl-Sepharose column chromatography with specific activity of 163 U/mg protein. The molecular mass of the purified enzyme was estimated to be approximately 49.5 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme had a pH optimum at 5.5 and a temperature optimum at $55^{\circ}C$. The activity of the enzyme was completely inhibited by SDS (5 mM), and slightly enhanced by $Cu^{2+}$ (5 mM). The cellulase was active on CMC, konjac, barely glucan and lichenan, while it did not exhibit activity towards xylan, locust bean gum, and p-nitrophenyl-$\beta$-glucopyranoside. The predominant products resulting from the cellulase hydrolysis were cellobiose and cellotriose for cellooligosaccharides including cellotriose, cellotetraose and cellopentaose. The enzyme could hydrolyze cellooligosaccharides larger than cellobiose.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1295-1302
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• 2004

A gene encoding the mannanase of Bacillus subtilis WL-7, which had been isolated from Korean soybean paste, was cloned into Escherichia coli, and the gene product was purified from the culture filtrate of the recombinant E. coli. This mannanase gene, designated manA, consisted of 1,086 nucleotides, encoding a polypeptide of 362 amino acid residues. The deduced amino acid sequence was highly homologous to those of mannanases belonging to the glycosyl hydrolase family 26. The molecular mass of the purified mannanase was 38 kDa as estimated by SDS-PAGE. The enzyme had a pH optimum at 6.0 and a temperature optimum at $55^{\circ}C$. The enzyme was active on locust bean gum, konjak, guar gum, and lichenan, while it did not exhibit activity towards yeast mannan, laminarin, carboxymethylcellulose, $\beta$­glucan, xylan, and para-nitrophenyl-$\beta$-mannopyranoside.

• Journal of Mushroom
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• v.17 no.4
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• pp.275-283
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• 2019

Sparassis latifolia is a fungus abundant in β-glucan and amino acids and is highly valued as a medicinal mushroom. Among amino acids, γ-aminobutyric acid (GABA) is a free amino acid and has biological effects, such as increase/decrease of hypertension, improvement of cerebral blood flow, and prevention of dementia. In this study, biological elicitors were used to increase bioactive substances as a biofortification method. Sodium alginate extracted from seaweed (Sargassum horneri, Sargassum fulvellum, Sargassum fusiforme) were used as the elicitor. The levels of β-glucan and GABA in the mycelium and fruiting body grown by adding the elicitor to the medium were investigated. Addition of sodium alginate positively affected GABA production and negatively affected the β-glucan production in these fungi. Sodium alginates extracted from S. fulvellum induced the highest increase in GABA in the mycelium and fruiting bodies. Moreover, we investigated the effects of the extracts from mycelium and fruiting bodies on dendrite development in primary cortical neurons. We found that the extract from the fruiting bodies of sodium alginate treated fungi with increased levels of GABA inhibited the dendrite outgrowth of excitatory neurons, but not inhibitory neurons.