• Journal of the Korean Applied Science and Technology
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• v.15 no.3
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• pp.21-26
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• 1998

Polyvinyl alcohol[PVA] is useful for the production of water-soluble packaging, paper, textile sizes. PVA and Chitosan are known as biodegradable polymers. PVA/chitosan blend films were prepared by solution blends method in the weight ratio of chitosan for the purpose of useful biodegradable films. Thermal and mechanical properties of PVA/chitosan blend films such as DSC, impact strength, tensile strength and morphology by SEM were determined. As a result, The ratio of 10.0wt% PVA/chitosan blend films were similar to PVA. Blend films were completely degraded pH 4.0 better than 7.0, 10.0 in the buffer solution. Also, Blend films were rapidly degraded enzyme(${\beta}-glucosidase$) solution better than pH solution by Enzymolysis.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.629-632
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• 2001

The strain FJ1 isolated from a rotten wood showed high activity to hydrolysis of cellulosic materials. The strain produced largely enzymes related in hydrolysis of cellulose and hemicellulose, such as CMCase, xylanase, ${\beta}-glucosidase$ , and avicelase. The culture conditions(pH, temperature, inoculation concentration) and substrate specificity to various cellulosic materials were examined to elevate productivity of the enzymes. The enzyme activities of CMCase and xylanase were 13.5U/ml and 24.3U/ml in agitation culture using Mandel's medium, respectively. The high activity of the enzymes was earned when mixed cellulosic materials of rice straw, sawdust, and pulp as substrates, indicating that the strain FJ1 could use crystalline substrates.

• Ecology and Resilient Infrastructure
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• v.4 no.2
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• pp.93-96
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• 2017

Spatial variations of physicochemical and microbiological variables were examined to understand spatial heterogeneity of those variables in intertidal flat. Variograms were constructed for understanding spatial autocorrelations of variables by a geostatistical analysis and spatial correlations between two variables were evaluated by applications of a Cross-Mantel test with a Monte Carlo procedure (with 999 permutations). Water content, organic matter content, pH, nitrate, sulfate, chloride, dissolved organic carbon (DOC), four extracellular enzyme activities (${\beta}-glucosidase$, N-acetyl-glucosaminidase, phosphatase, arylsulfatase), and bacterial diversity in soil were measured along a transect perpendicular to shore line. Most variables showed strong spatial autocorrelation or no spatial structure except for DOC. It was suggested that complex interactions between physicochemical and microbiological properties in sediment might controls DOC. Intertidal flat sediment appeared to be spatially heterogeneous. Bacterial diversity was found to be spatially correlated with enzyme activities. Chloride and sulfate were spatially correlated with microbial properties indicating that salinity in coastal environment would influence spatial distributions of decomposition capacities mediated by microorganisms. Overall, it was suggested that considerations on the spatial distributions of physicochemical and microbiological properties in intertidal flat sediment should be included when sampling scheme is designed for decomposition processes in intertidal flat sediment.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.1-8
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• 2003

Strain FJI, a filamentous fungus isolated from rotten wood, showed high ability to hydrolyze cellulosic materials. To identify the strain FJI, ITS sequencing analysis and morphological observation were performed. The strain FJI was identified as Trichoderma harzianum. The strain produced a large amount of CMCase, xylanase, ${\beta}-glucosidase$, and avicelase. Optimal culture conditions for the production of the enzymes, such as pH, temperature, and inoculation concentration, were initial pH 6.0-7.0,$25-30^{\circ}C$, and $10^4$ ea-spores/ml in Mandel's medium, respectively. T.hanzianum FJI utilized various cellulosic materials and organic nitrogen sources to produce cellulases and xylanase, and also considerably a crystalline and/or insoluble material like Avicel and rice straw. The highest levels of CMCase and xylanase were 41.2 and 65.6 U/ml in 7 days of cultivation using 2.5% of carbon source (Avicel+CMC) and 0.5% of nitrogen source (peptone), respectively.

• Journal of Ecology and Environment
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• v.33 no.2
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• pp.133-139
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• 2010

Atmospheric $CO_2$ concentrations have increased exponentially over the last century and, if continued, are expected to have significant effects on plants and soil. In this study, we investigated the effects of elevated $CO_2$ on the growth of Pinus densiflora seedling and microbial activity in soil. Three-year-old pine seedlings were exposed to ambient as well as elevated levels of $CO_2$ (380 and 760 ppmv, respectively). Growth rates and C:N ratios of the pine seedlings were also determined. Dissolved organic carbon content, phenolic compound content, and microbial activity were measured in bulk soil and rhizosphere soil. The results show that elevated $CO_2$ significantly increased the root dry weight of pine seedling. In addition, overall N content decreased, which increased the C:N ratio in pine needles. Elevated $CO_2$ decreased soil moisture, nitrate concentration, and the concentration of soil phenolic compounds. In contrast, soil enzymatic activities were increased in rhizosphere soil, including ${\beta}$-glucosidase, N-acetylglucosaminidase and phosphatase enzyme activities. In conclusion, elevated $CO_2$ concentrations caused distinct changes in soil chemistry and microbiology.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.199-202
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• 2004

Cellulolytic bacterial strains have been isolated from the faeces of wild (blackbuck, Antilope cervicapra; nilgai, Baselophus tragocamelus chinkara, Gazella gazella spotted deer, Axis axis and hog deer, Cervus porcinus) and rumen liquor of domestic (sheep, Ovis aries) ruminants. Five best cellulose degrading bacterial isolates (Ruminococcus sp.) were used as microbial feed additive along with buffalo rumen liquor as inoculum to study their effect on digestibility of feed and enzyme production in in vitro conditions. The bacterial isolate from chinkara (CHI-2) showed the highest per cent apparent dry matter (DM) digestibility ($35.40{\pm}0.60$), true dry matter digestibility ($40.80{\pm}0.69$) and NDF ($26.38{\pm}0.83$) digestibility (p<0.05) compared to control ($32.73{\pm}0.56$, $36.64{\pm}0.71$ and $21.16{\pm}0.89$, respectively) and other isolates at 24 h of incubation with lignocellulosic feeds (wheat straw and wheat bran, 80:20). The same isolate also exhibited the highest activities of fibre degrading enzymes like carboxymethylcellulase, xylanase, ${\beta}$-glucosidase and acetyl esterase. The bacterial isolate from chinkara (Gazella gazella) appears to have a potential to be used as feed additive in the diet of ruminants for improving utilization of nutrients from lignocellulosic feeds.

• Journal of Oral Medicine and Pain
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• v.24 no.2
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• pp.137-143
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• 1999

Aucubin, the natural product, which is isolated from Aucuba japonica, has a variety of pharmacological effects such as liver-protective function, inhibition of liver RNA and protein biosynthesis, hypotensive activity and antimicrobial effect, etc. This study was performed to investigate the effects of iridoid compounds on wound healing. The author prepared 0.1% aucubin solution and 0.1% aucubin ointment as an active form, aucubigenin to which aucubin was converted by ${\beta}$-glucosidase. Artificial surgical wound was made on either 1cm lateral side of the dorsal midline along the axis of spine of Sprague-Dawley rats under sterile technique. Application of 0.1% aucubin solution or 0.1% aucubin ointment to surgical wound was done daily. Light microscopic examination was performed on the postsurgical 3 days, 5 days, and 9 days. The 0.1% aucubin solution group epithelialized earlier than the control group and the fibrosis of granulation tissue of both aucubin groups were more prominent than the control group. Collectively, this study suggests the possibility of aucubin as a topical agent. Further research should be performed on the mechanism of aucubin on wound healing and proper formulation for effective topical agents.

• KSBB Journal
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• v.11 no.5
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• pp.511-517
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• 1996

An amphiphilic phase enzyme reaction was used to synthesize alkyl glucosides from glucose and alkyl alcohol with immobilized ${\beta}$-glucosidase using four glycol ether cosolvents(monoglyme, diglyme, 2-methoxyethanol, and 1,4-dioxane). Monoglyme was shown to be the best cosolvent for the amphiphilic phase medium composed of water/cosolvent/alkyl alcohol admixture. To obtain high yield of alkyl glucoside by amphiphilic phase enzyme reaction, hydrophilicity-hydrophobicity of amphiphilic media and enzyme microenvironment was optimized from the viewpoints of substrate solubility, enzyme activity, water activity, and dynamic equilibrium between glucose alcoholysis and glucoside hydrolysis. Under optimum reaction conditions, the highest concentrations of hexyl, octyl, decyl, and dodecyl glucosides were 18.2, 9.68, 7.27, and 6.03g/L, respectively.

• Journal of the Korean Graphic Arts Communication Society
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• v.24 no.1
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• pp.59-66
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• 2006

We studied on the effects of the enzyme treatment of pulp fiber on physical properties of coated paper were elucidated using four types of enzymes. The results of this study showed that the blank in which enzyme was not treated showed the highest $St{\ddot{o}}ckigt$ and Hurcules sizing degrees. And when the enzyme treated base paper was used for coating, the coated paper has average 5.7 % higher gloss and whiteness than when untreated base paper was used. Brightness showed 0.12 % higher results with the enzyme treated base papers than the blank while it is considered to show similar trends. Whiteness of coated paper was not influenced by the enzyme treatments but by the properties of coating color. Coated paper whose base paper was enzyme treated showed improved roughness while smoothness of those samples except the ${\beta}$-Glucosidase treated one was relatively low due to the high fines content. Also the coated paper whose base paper was not enzyme treated showed high porosity.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.340-345
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• 1999

A novel simultaneous saccharification and fermentation (SSF) process from the microcrystalline cellulose to ethanol was developed by using $\delta$-integrated recombinant cellulolytic Saccharomyces cerevisiae L2612$L2612\deltaGC$, which can utilize cellulose as carbon and energy sources. The optimum amount of enzymes needed for the efficient conversion of cellulose to ethanol at $30^{\circ}C$ was determined with commercial cellulolytic enzymes. By fed-batch cultivation, the heterologous cellulolytic enzymes were accumulated up to 42.67% of the total cellulase and 29% of the $\beta$-glucosidase needed for the efficient SSF process. When this $\delta$-integrated recombinant yeast was applied to the successive SSF step for ethanol production, 20.35 g/l of ethanol was produced after 12 h from 50 g/l of microcrystalline cellulose. By using this novel SSF process, a considerable amount of commercial enzymes was reduced.