• Korean Journal of Microbiology
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• v.25 no.4
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• pp.304-308
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• 1987

The mode of transglycosylation reaction observed during the action of low-molecular-weight 1,4-$\beta$-D-glucan glucanohydrolase (EC 3.2.1.4) purified from Trichoderma koningii ATCC 26113 was investigated using $^{1}H-NMR $spectroscopy. The H-1 proton resonances were analysed. After reaction of the enzyme with cellotriose, the reaction products were separated by high performance liquid chromatography. H-1 resonances of the products were consisted with those of cellobiose, cellotriose and cellotitraose, respectively. Therefore it was proved that all the reaction products formed by the action of the enzyme on cellooligosaccharides, including transglycosylation products, possess only H-NMR -1,4-glycosidic linkage(s).

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.689-695
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• 1996

In order to prove physiological function of ${\beta}-Glucan$ isolated from barley flour by enzymatic method, in vitro experiments simulating the passive membrane transport of gastrointestinal tract were carried out using dialysis membrane. The yield of ${\beta}-Glucan$ from barley flour was $6.2{\%}$ and its constituents were determined to give $81.6{\%}$ total dietary fiber, $72.9{\%}$ soluble dietary fiber, $8.7{\%}$ insoluble dietary fiber, $8.5{\%}$ moisture, $2.5{\%}$ protein and $7.4{\%}$ ash. The water holding capacity of the ${\beta}-Glucan$ preparation was 6 g water/g dry material. The glucose retardation index after 30 minute dialysis was $13.5{\%}$ in the presence of $3{\%}$ ${\beta}-Glucan$. As the dialysis period became longer, the retarding effect toward glucose absorption decreased and the effect was close to zero after 2 hour dialysis. The bile acid retardation index after 30 minute dialysis was 3, 12 and $18{\%}$ in the presence of 1, 3 and $5{\%}$ ${\beta}-Glucan$, respectively. The effect was higher than the glucose retardation index and decreased as the dialysis time elapsed.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.146-151
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• 2008

In this study, batch or semi-continuous reactions, introducing site-specific carboxylic acids in ${\beta}$-1,3-glucan structures, were performed to increase water solubility and gel forming ability, using TEMPO/hypobromite with or without NaBr as catalysts. Regio-selective carboxylic acid formations were determined with infrared (IR) and $^{13}C$ nuclear magnetic resonance (NMR) spectroscopic analyses. The regio-selective reactions with and without NaBr gave oxidation yields of 92.5 and 85.6%, respectively, in the batch type, and yields of 93.9 and 86.4%, respectively, in the semi-continuous type. The reaction times in the batch and semi-continuous reactions without NaBr were delayed by 100 and 150%, respectively, as compared to those with NaBr. A combination of IR and $^{13}C$ NMR analyses were used to confirm the formation of carboxylic acids in ${\beta}$-1,3-glucan. From the batch reactions with and without NaBr, the water solubilities of oxidized products were 50.0 and 55.6%, respectively, and in the semi-continuous reactions they were 52.6 and 53.5%, respectively; while the water solubility of the native ${\beta}$-1,3-glucan was less than 1.0%. Finally, as compared to the native ${\beta}$-1,3-glucan, the gel forming ability of the reaction products was greatly increased irrespective of the presence of NaBr or the reaction type.

• The Korean Journal of Mycology
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• v.23 no.2 s.73
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• pp.129-138
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• 1995

DNA fragment being able to restore in vitro activity of ${\beta}-1,3-glucan$ synthase was cloned by transformation of the Saccharomyces cerevisiae LP353 mutant strain with genomic library constructed in the YCp50. For the selection of transformants which showed no detectable phenotype linked to recovery of the defect in ${\beta}-1,3-glucan$ synthase activity, the colony autoradiography was succesfully applied. The restriction map of the cloned DNA fragment, which is 8.5-kb in length, was constructed. Both the YEplac195 and the YCp50 carrying the 8.5-kb fragment increased ${\beta}-1,3-glucan$ synthase activity of LP353 by two fold. Neither the YEplac195 nor the YCp50 carrying the 8.5-kb DNA fragment, however, complemented the temperature-dependent osmotic sensitivity which is another distinctive phenotype of LP353. Subcloning experiments indicated that a functional region was located in 4.8-kb BglII-KpnI fragment. The 4.8-kb fragment was also able to increase the level of ${\beta}-1,3-glucan$ content in cell wall as well as the resistance of cells to cell wall lytic enzyme, ${\beta}-1,3-glucanase$. The growth rate of the LP353 with 4.8-kb fragment was almost same as that of wild type strain in liquid medium with 1.2 M sorbitol at nonpermissive temperature. Taken these results together, the 4.8-kb fragment seemed to contain the BGS2 gene for ${\beta}-1,3-glucan$ synthase activity in yeast S. cerevisiae.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.180-182
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• 1992

Three hull-less barleys and three covered barleys grown in Korea were pearled to give 0% and 60% yield, respectively. Whole barleys and pearled barleys were analyzed for total, insoluble, soluble dietary fiber and ${\beta}-glucan$ contents. Whole hull-less barleys contained average 17.1% total dietary fiber, and whole covered barleys contained average 23.9% total dietary fiber. Pearled hull-less barleys contained 9,2% total dietary fiber and 4.8% solule dietary fiber. Pearled covered barleys contained 11.9% total dietary fiber and 6.0% soluble dietary fiber. Whole barleys contained $3.2{\sim}3.9%$ (${\beta}-glucan$, and pearled barleys contained $3.5{\sim}5.4%$ (${\beta}-glucan$. Soluble dietary fiber and (${\beta}-glucan$ contents of barley were not affected by cooking, while insoluble dietary fiber content was increased by cooking.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.284-291
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• 2011

Varietal and annual variations in the contents of ${\beta}$-glucan fractions per weight grain samples were examined in sixteen covered and eighteen naked barley and five oat cultivars developed in Korea. Also, the effect of pearling on ${\beta}$-glucan content was investigated. Average contents of total, soluble and insoluble ${\beta}$-glucan fractions were 5.25, 3.72, and 1.53%, respectively, in covered barley, and 5.86, 3.51, and 2.35%, respectively, in naked barley. Soluble ${\beta}$-glucan content was higher in covered barley, though total ${\beta}$-glucan content higher in naked barley. The total and insoluble ${\beta}$-glucan contents were higher in pearled grains. Total ${\beta}$-glucan content was higher in waxy barley than in non-waxy barley. Duwonchapssalbori, a two-rowed and waxy naked barley cultivar, was highest in total, soluble and insoluble ${\beta}$-glucan contents. Highly significant positive correlations were observed between total ${\beta}$-glucan and soluble ${\beta}$-glucan contents both in covered and naked barley. There were significant annual variations in total ${\beta}$-glucan content in barley. Average contents of total, soluble and insoluble ${\beta}$-glucans of oat cultivars were 4.33, 3.44, and 0.89%, respectively. Contents of all fractions of ${\beta}$-glucans were higher in barley than in oat. These results would be useful for the breeding of high ${\beta}$-glucan variety and also for the use barley and oat as valueadded food ingredients.

• Mycobiology
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• v.42 no.3
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• pp.301-304
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• 2014

Shiitake mushrooms (Lentinula edodes) containing ${\beta}$-glucans may be beneficial for human health; they have been used in the treatment of cancer, hypertension, and high cholesterol levels. The objective of this study was to determine the ${\beta}$-glucan content in different sections of the fruiting bodies and mycelia of ten shiitake mushroom cultivars. The measured ${\beta}$-glucan content ranged from $20.06{\pm}1.76%$ to $44.21{\pm}0.13%$ in the pileus sections, and from $29.74{\pm}1.40%$ to $56.47{\pm}4.72%$ in the stipe sections. The results of this study indicate that the variance in ${\beta}$-glucan content dependent on the shiitake cultivar, and that the ${\beta}$-glucan content is higher in the stipe than in the pileus.

• Nutrition Research and Practice
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• v.11 no.1
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• pp.43-50
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• 2017

BACKGROUND/OBJECTIVES: The present study investigated the hypothesis that a highly pure linear ${\beta}$-1,3-glucan produced by Agrobacterium sp. R259 enhances human natural killer (NK) cell activity and suppresses pro-inflammatory cytokines. SUBJECTS/METHODS: In an eight-week, double-blind, randomized, placebo-controlled clinical trial, 83 healthy adults with white blood cell counts of $4,000-8,000cells/{\mu}L$ were participated and randomly assigned to take two capsules per day containing either 350 mg ${\beta}$-1,3-glucan or placebo. Six participants withdrew their study consent or were excluded due to NK cell activity levels outside the normal range. NK cell activity and serum levels of immunoglobulin G (IgG) and cytokines, such as interferon (IFN)-${\gamma}$, interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12 and tumor necrosis factor (TNF)-${\alpha}$ were measured. RESULTS: NK cell activity and the serum levels of IL-10 were significantly higher from baseline to week 8 in the ${\beta}$-glucan group compared with the placebo group (P = 0.048, P = 0.029). Consumption of ${\beta}$-1,3-glucan also significantly increased NK cell activity compared with placebo after adjusting for smoking and stress status (P = 0.009). In particular, the effect of ${\beta}$-1,3-glucan on NK cell activity was greater in participants with severe stress than in those experiencing mild stress. However, the administration ${\beta}$-1,3-glucan did not significantly modulate the levels of IFN-${\gamma}$, IL-2, IL-4, IL-6, IL-12, TNF-${\alpha}$ and IgG compared with the placebo. CONCLUSION: The results showed that supplementation with bacterial ${\beta}$-1,3-glucan significantly increased NK cell activity without causing any adverse effects. Additionally, the beneficial effect of ${\beta}$-1,3-glucan on NK cell activity was greater in participants experiencing severe stress.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.590-597
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• 2000

The rheological properties of ${\beta}-glucans$ isolated from non-waxy and waxy barley were investigated. ${\beta}-Glucan$ solutions showed pseudoplastic properties and their behaviors were explained by applying Power law model in the range of concentrations$(1{\sim}4%)$ and temperatures$(20{\sim}65^{\circ}C)$. The effects of temperature and concentration on the apparent viscosity at $700\;s^{-1}$ shear rate were examined by applying Arrhenius equation and power law equation, and their effect was more pronounced in waxy ${\beta}-glucan$ solutions. The activation energy for flow of ${\beta}-glucan$ solutions decreased with the increase of concentration, and the concentration-dependent constant A increased with the increase of temperature. The intrinsic viscosity of waxy ${\beta}-glucan$ was higher than that of non-waxy ${\beta}-glucan$. The transition from dilute to concentrate region occurred at a critical coil overlap parameter $C^*[{\eta}]=0.02.$ The slopes of non-waxy and waxy ${\beta}-glucan$ at $C[{\eta}] were similar, but the slope of waxy ${\beta}-glucan$ at $C[{\eta}]>C^*[{\eta}]$ was higher than that of non-waxy ${\beta}-glucan$. Dynamic viscoelasticity measurement showed that cross-over happened, and storage modulus was higher than loss modulus at frequency range above cross-over. ${\beta}-Glucan$ solutions formed weak gels after stored for 24 hr.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.351-355
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• 2018

Treatment towards wound healing, a complex and dynamic process, has been given a great deal of efforts in the last few decades. Focus has been imposed on developing wound dressings that meet the requirements for proper wound healing. In this study, hydrogel made from blends of poly (vinyl alcohol) and ${\beta}$-1,6-branched-${\beta}$-1,3-glucan (beta-glucan) were synthesized by modified solvent casting method for wound dressing application. Optimization of hydrogel composition and analysis of wound dressing parameters such as stability and fluid uptake capacity (in the presence of water, saline and different pH solutions) has been studied. The result indicated that the PVA/beta-glucan hydrogel hold its structural integrity even at alkaline pH (pH~9) and upholds fluids four times of its original weight. Thus, the developed hydrogel is expected to be a promising candidate as wound dressing.