• Food Science and Biotechnology
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• v.17 no.5
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• pp.1021-1024
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• 2008

Genistein, one of the isoflavones in doenjang, is generally known to prevent various cancers, osteoporosis, climacterium, and menopause symptoms, and has better bioavailability and healthful physiological effects than its glucoside, genistin. In both traditional and commercial doenjangs, genistein content ranged from 370 to 1,510 mg/kg, however, significant amounts of genistin also existed at the level of 190 to 350 mg/kg. After treating with corn $\beta$-glucosidase, over 84% of genistin in doenjang was converted to genistein. However, physiochemical characteristics such as pH, viscosity, 2-thiobarbituric acid (TBA) value, and color were not changed significantly after corn $\beta$-glucosidase treatments. Therefore, this study shows that the improved doenjang with the increased genistein content can be produced using corn $\beta$-glucosidase.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.260-266
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• 2009

The effects of ${\beta}$-glucosidase on the overall growth performance and a set of physiological parameters of broilers were investigated. 240 male, one-day old Avine broiler chickswere randomly allocated to four treatment groups and fed with a corn-soybean meal supplemented with 0% (control), 0.2%, 0.4% and 0.6% ${\beta}$-glucosidase. The 0.2% ${\beta}$-glucosidase group, but not the 0.4% and 0.6% ${\beta}$-glucosidase groups, showed a significantly increased average daily weight gain (p<0.05) over that of the control. All three ${\beta}$-glucosidase feed groups showed significantly higher feed conversion ratios than the control group (p<0.05). Feed supplementation of 0.2% ${\beta}$-glucosidase significantly raised the contents of serum isoflavone aglycones as shown by decreases of genistin and daizin (p<0.01) and an increase of daidzein (p<0.01). The 0.2% ${\beta}$-glucosidase feeding significantly increased the intestinal amylase activity while it had little effect on lipase and trypsin activities (p>0.05). 0.2% ${\beta}$-glucosidase feeding also significant elevated the levels of highdensity lipoprotein cholesterol and malate dehydrogenase while lowering the level of low-density lipoprotein cholesterol (LDL-C). Finally, ${\beta}$-glucosidase improved the anti-oxidative activities of the animals; the 0.2% ${\beta}$-glucosidase feed group had higher activities of superoxide dismutase (p<0.05), glutathione peroxidase and glutathione reductase in the liver (p<0.05), and malondialdehyde level in the serum (p<0.05).

• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1427-1437
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• 2014

Enzymatic hydrolysis of lignocellulosic biomass into fermentable sugars is a key step in the conversion of agricultural by-products to biofuels and value-added chemicals. Utilization of a robust microorganism for on-site production of biomass-degrading enzymes has gained increasing interest as an economical approach for supplying enzymes to biorefinery processes. In this study, production of multi-polysaccharide-degrading enzymes from Aspergillus aculeatus BCC199 by solid-state fermentation was improved through the statistical design approach. Among the operational parameters, yeast extract and soybean meal as well as the nonionic surfactant Tween 20 and initial pH were found as key parameters for maximizing production of cellulolytic and hemicellulolytic enzymes. Under the optimized condition, the production of FPase, endoglucanase, ${\beta}$-glucosidase, xylanase, and ${\beta}$-xylosidase was achieved at 23, 663, 88, 1,633, and 90 units/g of dry substrate, respectively. The multi-enzyme extract was highly efficient in the saccharification of alkaline-pretreated rice straw, corn cob, and corn stover. In comparison with commercial cellulase preparations, the BCC199 enzyme mixture was able to produce remarkable yields of glucose and xylose, as it contained higher relative activities of ${\beta}$-glucosidase and core hemicellulases (xylanase and ${\beta}$-xylosidase). These results suggested that the crude enzyme extract from A. aculeatus BCC199 possesses balanced cellulolytic and xylanolytic activities required for the efficient saccharification of lignocellulosic biomass feedstocks, and supplementation of external ${\beta}$-glucosidase or xylanase was dispensable. The work thus demonstrates the high potential of A. aculeatus BCC199 as a promising producer of lignocellulose-degrading enzymes for the biomass conversion industry.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.547-560
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• 2010

The optimum culture condition of Schizophyllum commune for the cellulase production and its enzymatic characteristics for saccharification of cellulosic biomass were analyzed. S. commune secrets ${\beta}$-1,4-xylosidase (BXL) and cellulases, including endo-${\beta}$-1,4-glucanase (EG), cellobiohydrolase (CBH), and ${\beta}$-glucosidase (BGL). The optimum reaction temperature for all cellulases was $50^{\circ}C$ and the thermostable range was $30{\sim}40^{\circ}C$C. The optimum reaction pH for all cellulases was 5.5 in a range of temperature from $0^{\circ}C$ to $55^{\circ}C$. The best nutritions for the cellulase production of S. commune among tested nutrients were 2% cellulose for the carbon source and corn steep liquor or peptone/yeast extract for the nitrogen source without vitamins. The environmental culture condition for the cellulase production was 5.5~6.0 for pH at $25{\sim}30^{\circ}C$. The enzyme activities of EG, BGL, CBH, and BXL were 3670.5, 631.9, 398.5, and 15.2 U/$m{\ell}$, respectively, after concentration forty times from the culture broth of S. commune which was grown at the optimized culture condition. Alternative filter paper unit assay showed 11 FPU/$m{\ell}$ enzyme activity. The saccharification tests using cellulase of S. commune showed the low saccharification rate on tested hardwoods but a high value of 50.5% on cellulose, respectively. The saccharification rate (50.5%) of cellulose by cellulase produced in this work is higher than 45.7% in the commercial enzyme (Celluclast 1.5L, 30 FPU/g, glucan).

• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.284-292
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• 2011

An endocellulase-free multienzyme complex was produced by a thermophilic anaerobic bacterium, Thermoanaerobacterium thermosaccharolyticum strain NOI-1, when grown on xylan. The temperature and pH optima for growth were $60^{\circ}C$ and 6.0, respectively. The bacterial cells were found to adhere to insoluble xylan and Avicel. A scanning electron microscopy analysis showed the adhesion of xylan to the cells. An endocellulase-free multienzyme complex was isolated from the crude enzyme of strain NOI-1 by affinity purification on cellulose and Sephacryl S-300 gel filtration. The molecular mass of the multienzyme complex was estimated to be about 1,200 kDa. The multienzyme complex showed one protein on native PAGE, one xylanase on a native zymogram, 21 proteins on SDS-PAGE, and 5 xylanases on a SDS zymogram. The multienzyme complex consisted of xylanase, ${\beta}$-xylosidase, ${\alpha}$-L-arabinofuranosidase, ${\beta}$-glucosidase, and cellobiohydrolase. The multienzyme complex was effective in hydrolyzing xylan and corn hulls. This is the first report of an endocellulase-free multienzyme complex produced by a thermophilic anaerobic bacterium, T. thermosaccharolyticum strain NOI-1.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.41-48
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• 2000

A bacterial strain, designated as JK-43, producing extracellular cyclodextrin glucanotransferase (CGTase)[EC 2.4.1.19] was isolated from kimchi. The CGTase from isolated strain JK-43 showed the transglucosylation activity from soluble starch to L-ascorbic acid(AA) compared to those obtained from other strains. A main product formed by this reaction was identified as $2-O-{\alpha}-glucopyranosyl$ L-ascorbic acid(AA-2G) by testing its susceptibility to ${\alpha}-glucosidase$ hydrolysis, the HPLC profiles, and through the elementary analysis. the ${\beta}-CD,\;{\gamma}-CD$, potato starch and corn starch were identified to be suitable glucosyl donor for transglucosylation reaction on AA by CGTase. Acceptor specificity on AA-2G production was examined by use of AA, Iso-AA and AA-2P. Transglucosylation was observed toward AA-2P as well as AA and Iso-AA. The microorganism isolated from kimchi was identified as a strain of Bacillus sp. JK-43 based on the morphological, cultural, biochemical characteristics and partial 16SrDNA sequence analysis. The maximal CGTase production was observed in a medium containing 1.0% soluble starch, 1.0% yeast extract, 1.0% $Na_2CO_3\;0.1%\;K_2HPO_4,\;and\;0.02%\;MgSO_4{\cdot}7H_2O$ with initial pH 7.0. The strain was cultured at $37^{\circ}C$ for 26 hrs with reciprocal shaking.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.105-110
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• 1984

Seven seed samples of corn obtained from Kangweon Provincial Office of Rural Development, Kerea were tested for seed-borne fungi, and found that all the samples tested were infected with Fusarium moniliforme to an extent of $6.0{\sim}79.5%$. Severely infected seed samples showed poor germination on blotter. Seed component plating showed that the fungus present not only in tip caps, pericarps and endosperms, but also in embryos. Heavy infection of the fungus caused severe seed rot and seedling blight in soil, but the damage was not severe and many plants grew without any symptoms when the seeds with light infection were sown in soil. However the fungus was frequently detected from inside of the stems of healthy looking seedlings. The results indicate that the fungus transmit from seed to plant systemically. In inoculation experiments, the fungus produced stem rots on corn plants of 110 days old. The cultivar of Hwangok 3 was revealed more susceptible to the fungus than that of Suweon 19.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.164-167
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• 2005

The culture condition and medium composition for the enhanced mycelial growth of Lepista nuda DGUM 26501 were investigated. The optimal temperature and pH for the mycelial growth were $24^{\circ}C$ and $7.0\~8.0$, respectively. The partial pressure of oxygen for the enhanced mycelial growth was more than $10\%\;O_2$. When Czapek-Dox medium was used as a minimal medium, manitol and xylitol were very good carbon sources. Organic nitrogen sources were better than inorganic ones for mycelial growth. As the nitrogen source tested, com steep liquor, soytone and protease peptone were the best as a source of organic nitrogen sources. When ammonium phosphate as phosphorus sources was used, the enhanced mycelial growth was shown. Nicotinic acid was proved to be the most appropriate source of vitamin. After the mycelia of L. nuda DGUM 26501 was cultivated at $24^{\circ}C$ for 10 days in LNM broth (pH 7.0), the activities of extracellular enzyme were determined. The specific activity of $\alpha-amylase$ was much higher than those of other enzymes. However, little or no enzyme activities of $\beta-glucosidase$, CMCase, laccase and lipase were found.