• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.792-799
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• 2007

A gene encoding a putative glycogen-debranching enzyme in Sulfolobus shibatae(abbreviated as SSGDE) was cloned and expressed in Escherichia coli. The recombinant enzyme was purified to homogeneity by heat treatment and Ni-NTA affinity chromatography. The recombinant SSGDE was extremely thermostable, with an optimal temperature at $85^{\circ}C$. The enzyme had an optimum pH of 5.5 and was highly stable from pH 4.5 to 6.5. The substrate specificity of SSGDE suggested that it possesses characteristics of both amylo-1,6-glucosidase and $\alpha$-1,4-glucanotransferase. SSGDE clearly hydrolyzed pullulan to maltotriose, and $6-O-\alpha-maltosyl-\beta-cyclodextrin(G2-\beta-CD)$ to maltose and $\beta$-cyclodextrin. At the same time, SSGDE transferred maltooligosyl residues to the maltooligosaccharides employed, and maltosyl residues to $G2-\beta-CD$. The enzyme preferentially hydrolyzed amylopectin, followed in a decreasing order by glycogen, pullulan, and amylose. Therefore, the present results suggest that the glycogen-debranching enzyme from S. shibatae may have industrial application for the efficient debranching and modification of starch to dextrins at a high temperature.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.53-57
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• 1996

As the production of chonma became increased by the farmer's cultivation, developments of the processed food such as tea using chonma have been actively pursued. In the present study, the components of chonma and its beneficial effects on health using SD (Sprague-Dawley) rat model were analyzed. The contents of moisture, protein, ash, fat and fiber in dried-chonma were 11.8, 7.6, 3.2, 0.5, and 3.9%(w/w), respectively. The contents of calcium, sodium, iron, phosphorus, magnesium and potassium were 121, 83, 6.2, 170, 69 and 1,278 mg%. When chow diets containing 0, 0.15, 1.5 or 5.0% chonma powder were fed to SD rats for 4 weeks, no significant differences were observed in the composition of the large-intestinal flora, ${\beta}-glucuronidase$ level of the large-intestinal contents and the weight gains of rats. The level of ${\beta}-glucosidase$ was higher and the serum cholesterol level was lower in 5.0% chonma group compared with control group. The highest sedative effect was shown in 0.15% chonma group.

• The Korea Journal of Herbology
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• v.32 no.4
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• pp.47-52
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• 2017

Objective : Phellinus spp. mushroom is an object of interest because it has excellent anticancer effect. Owing to the similalarities in the morphology, Phellinus linteus and Phellinus baumii are often used as same Sang Hwang Mushroom in the Korean market.. The quality control for mushrooms is needed because there are many differences in the efficacy according to cultivation method and cultivation area. Therefore, a reliable authentication method of these herbal medicine is necessary to compare and measure the amount of beta-glucan which is known to have a hypoglycemic effect, from the mushrooms collected in various regions Methods : 7 samples of medicinal mushrooms supplying phellinus spp. were collected in Korea, China and Cambodia. We investigated the hardness, colors, extract ratio, ${\alpha}-amylase$ and ${\alpha}-glucosidase$ inhibitory activities, glucose transporter 4 (GLUT-4) expressions of water extracts from Phellinus spp and also MTT assay were examined for cell toxicity. Results : The results revealed that Phellinus spp.water Ext.inhibited ${\alpha}-glucosidase$ activity. glucose transporter 4 (GLUT-4), the key insulin signaling pathway transcription factor, was remarkably increased by the Phellinus baumii water extract Conclusions : These results suggest that The more yellowish the mushroom is, the lower the hardness, the more the content of ${\beta}-glucan$ is proportional. Because the more ${\beta}-glucan$, the greater the effect of hypoglycemia. compared to the hypoglycemic effect, Phellinus Baumii grown at hanging on selves for 7 month in the green house is the best.

• Journal of Wetlands Research
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• v.14 no.1
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• pp.47-57
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• 2012

We have measured soil enzyme activities, which represent the rates of organic matter decomposition, in four riparian ecosystems in Korea. ${\beta}$-glucosidase, N-acetylglucosaminidase, phosphatase and arylsulfatase activities were determined in five occasions over a year period in soils of control plots and plots with invasive plants, namely Sicyos angulatus and Humulus japonicus. Significantly higher enzyme activities were found in soils with invasive plant in barren land, but the difference was season and enzyme-specific. Although it was not universal changes, the invasive plants appeared to accelerate organic matter decomposition in some disturbed riparian ecosystems.

• KSBB Journal
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• v.14 no.1
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• pp.24-30
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• 1999

The fed-bach simultaneous saccharification and fermentation (SSF) of newspaper to ethanol with Brettanomyces custersii was studied. The initial substrate concentration for the effective fed-batch SSF was 8% (w/v). The initial optimum enzyme concentration was 30 FPU/g cellulose for cellulase and the optimum volumetric ratio of $\beta$-glucosidase to cellulase was 0.1. When 4% (w/v) of ball-milled newspaper was supplemented intermittently at time intervals, considering the mixing of newspaper slurry, the fed-batch SSF showed higher ethanol concentration (26.80 g/L) and two times higher ethanol production yield based on enzyme than the batch SSF.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.383-389
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• 1990

During the cultivation of Penkillium uerrmulosum in the media containing cellobiose octaacetate (COA), avicel, or KC-flock as an inducer and as a sole carbon source for 21 days, cellulolytic activity and SDS-PAGE pattern of proteins in the culture broth were investigated. Protein concentration and cellulolytic activity were highest in the COA medium. As cultivation period was increased, protein content and avicel hydrolytic activity of culture broth were increased as similar extent but neither $\beta$-glucosidase nor CMC hydrolytic activity was correlated to protein content. When crude proteins from the culture broth were separated on DEAE column by HPLC, distribution of avicel-hydrolytic activities were well correlated with that of major proteins. From those results it was suggested that three major proteins having 60 K, 68 K, and 76 K of Mr. were avicel-hydrolytic enzymes.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.496-501
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• 1998

The mycelia of Tricholoma matsutake DGUM 26001, 26101, 26210 and FRI 91024 were used to determine the extracellular enzyme activity in mycelia. When the filtrate of culture broth after 30-day cultivation at $24^{\circ}C$ was used as a crude solution of extracellular enzyme, the average specific activity of ${\alpha}-amylase$ was 6142.3 unit/mg protein. The specific activity of xylanase was comparatively high. However, little or no enzyme activities were found for ${\beta}-glucosidase$, ligninase, CMCase, chitinase, protease, and lipase.

• Korean Journal of Pharmacognosy
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• v.16 no.2
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• pp.99-104
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• 1985

To investigate a possible biological activity of iridoid glucosides, six compounds, aucubin, catalpol, gardenoside, geniposide, rehmannioside and swertiamarin, were studied in relation with their potential influences in RNA and protein biosyntheses in murine tumor cell, sarcoma 180, in vitro. Protein biosynthesis was slightly inhibited by aucubin, gardenoside and swertiamarin. Degree of inhibition of RNA biosynthesis by those iridoid appeared to be more sensitive than that of protein biosynthesis. When aucubin was pretreated with ${\beta}-glucosidase$ to produce its genin form and the sarcoma 180 cells were exposed to this aucubigenin, the protein and RNA biosyntheses in the cells were profoundly inhibited. The results indicate that a biologically active from of iridoid compounds is the hydrolytic products of glycoside, i.e. genin form. It is also suggested that sarcoma 180 cells used in the experiments appear to lack of ${\beta}-glucosidase$, since the inhibitory actions of iridoid glucosides were so slight that those glucosides were not hydrolysed by the enzyme to their genin forms.

• 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.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.87-91
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• 1997

Isomaltooligosaccharides in Sikhye were digested with enzyme (30unit/ml) of $\alpha$-amylase, $\alpha$-glucosidase and glucoamylase from Aspergillus awamori, sweet potato $\beta$-amylase and human salivary $\alpha$-amylase at 37$^{\circ}C$ for 1 hour, respectively. These amylases acted on these saccharides to give hydrolysis products with less than 20% of degree of hydrolysis, except the case of glucoamylase with 62% of high degree of hydrolysis. $\alpha$-Glucosidase plus human salivary $\alpha$-amylase hydrolyzed it to attain the hydrolysis value up to 25%, but further increment of hydrolysis was not observed. Rice residue in Sikhye has similar sugar composition and structure, judging from sugar analyses by the enzymatic hydrolysis. These results suggest that isomaltooligosaccharides and rice residue in Sikhye can be a growth factor for Bifidobacterium and dietary fiber which is useful for human health.