• Journal of Microbiology and Biotechnology
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• v.20 no.2
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• pp.254-264
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• 2010

To obtain an efficient natural lignocellulolytic complex enzyme, we screened an efficient lignocellulose-degrading composite microbial system (XDC-2) from composted agricultural and animal wastes amended soil following a long-term directed acclimation. Not only could the XDC-2 degrade natural lignocelluloses, but it could also secrete extracellular xylanase efficiently in liquid culture under static conditions at room temperature. The XDC-2 degraded rice straw by 60.3% after fermentation for 15 days. Hemicelluloses were decomposed effectively, whereas the extracellular xylanase activity was dominant with an activity of 8.357 U/ml on day 6 of the fermentation period. The extracellular crude enzyme noticeably hydrolyzed natural lignocelluloses. The optimum temperature and pH for the xylanase activity were $40^{\circ}C$ and 6.0. However, the xylanase was activated in a wide pH range of 3.0-10.0, and retained more than 80% of its activity at $25-35^{\circ}C$ and pH 5.0-8.0 after three days of incubation in liquid culture under static conditions. PCR-DGGE analysis of successive subcultures indicated that the XDC-2 was structurally stable over long-term restricted and directed cultivation. Analysis of the 168 rRNA gene clone library showed that the XDC-2 was mainly composed of mesophilic bacteria related to the genera Clostridium, Bacteroides, Alcaligenes, Pseudomonas, etc. Our results offer a new approach to exploring efficient lignocellulolytic enzymes by constructing a high-performance composite microbial system with synergistic complex enzymes.

• KSBB Journal
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• v.32 no.2
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• pp.96-102
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• 2017

The lignocellulose that is a major component of spent coffee ground was degraded and saccharified. To implement the spent coffee, after several pre-treatments, inoculation of Phanerochaete chrysosporium and solid-state fermentation were conducted. The optimal temperature of the enzymes (lignin peroxidase, manganese peroxidase, xylanase, laccase, and cellulase) for degradation of lignocellulose by P. chrysosporium was found. We also measured the maximum activity of enzymes (lignin peroxidase 0.15 IU/mL, manganese peroxidase 0.90 IU/mL, laccase 0.11 IU/mL, cellulase 5.87 IU/mL, carboxymethyl cellulase 9.52 IU/mL, xylanase 1.16 IU/mL) used for the process. As a result, 4.73 mg/mL of reduced sugar was obtained and 61.02% of lignin was degraded by solid state fermentation of P. chrysosporium on spent coffee ground.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.930-938
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• 2012

High levels of xylanase activity (143.98 IU/ml) produced by the newly isolated Paenibacillus campinasensis G1-1 were detected when it was cultivated in a synthetic medium. A thermostable xylanase, designated XynG1-1, from P. campinasensis G1-1 was purified to homogeneity by Octyl-Sepharose hydrophobic-interaction chromatography, Sephadex G75 gel-filter chromatography, and Q-Sepharose ion-exchange chromatography, consecutively. By multistep purification, the specific activity of XynG1-1 was up to 1,865.5 IU/mg with a 9.1-fold purification. The molecular mass of purified XynG1-1 was about 41.3 kDa as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Sequence analysis revealed that XynG1-1 containing 377 amino acids encoded by 1,134 bp genomic sequences of P. campinasensis G1-1 shared 96% homology with XylX from Paenibacillus campinasensis BL11 and 77%~78% homology with xylanases from Bacillus sp. YA-335 and Bacillus sp. 41M-1, respectively. The activity of XynG1-1 was stimulated by $Ca^{2+}$, $Ba^{2+}$, DTT, and ${\beta}$-mercaptoethanol, but was inhibited by $Ni^{2+}$, $Fe^{2+}$, $Fe^{3+}$, $Zn^{2+}$, SDS, and EDTA. The purified XynG1-1 displayed a greater affinity for birchwood xylan, with an optimal temperature of $60^{\circ}C$ and an optimal pH of 7.5. The fact that XynG1-1 is cellulose-free, thermostable (stability at high temperature of $70^{\circ}C{\sim}80^{\circ}C$), and active over a wide pH range (pH 5.0~9.0) suggests that the enzyme is potentially valuable for various industrial applications, especially for pulp bleaching pretreatment.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.529-532
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• 2001

Korean food waste, one of the abundantly available but environmentally problematic organic wastes in Korea, was utilized as solid-substrate by fungal strain Aspergillus niger ATcC 6275 for the production of enzymemixture containing amylase, cellulase and xylanase. The enzyme mixture can be used as high value-added animal feed. Solid-state fermentation method yielded a 84-fold enhancement in xylanase activity compared with submerged fermentation method. The effect of incubation period, incubation temperature, pH of medium, moisture content, inoculum size and enrichment of the medium with nitrogen and carbon sources were observed for optimal production of these enzymes The optimal amylase activity of 33.10 U/g, cellulase activity of 24.41 U/g, xylanase activity of 328.84 U/g were obtained at 8 days incubation with 50%(w/w) soy bean flake, with incubation temperature of $25^{\circ}C$, pH of 6.38, optimal moisture content of 55% and with inoculum size of $3.8{\times}10^6$spore/g. Enzyme activities were enhanced when ImM $CaSO_4$, 2% Malt extract and 2% galactose were added as mineral, nitrogen and carbon enrichment respectively.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.302-306
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• 2014

The present study was carried out to optimize fermentation parameters for the production of cellulolytic enzymes through solid substrate fermentation of Trichoderma reesei and Aspergillus niger grown on wheat straw. A sequential optimization based on one-factor-at-a-time method was applied to optimize fermentation parameters including temperature, pH, moisture content and particle size. The results of optimization indicated that $40^{\circ}C$, pH 7, moisture content 75% and particle size between 0.25~0.5 mm were found to be the optimum condition at 96 hr fermentation. Under the optimal condition, co-culture of T. reesei and A. niger produced cellulase activities of 10.3 IU, endoglucanase activity of 100.3 IU, ${\beta}$-glucosidase activity of 22.9 IU and xylanase activity of 2261.7 IU/g dry material were obtained. Cellulolytic enzyme production with optimization showed about 72.6, 48.8, 55.2 and 51.9% increase compared to those obtained from control experiment, respectively.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.561-567
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• 2010

In this study, we evaluated optimal conditions for ethanol production of the spruce hydrolysate (SH) obtained from diethyl oxalate pretreatment. Fermentable sugar concentration in SH was 29.04 g/${\ell}$ except arabinose. Monosaccharides obtained from the oligomer degradation were mainly mannose (39.26 g/${\ell}$) and galactose (12.83 g/${\ell}$). Concentration of 5-HMF and furfural which are inhibitors on ethanol fermentation were 0.09 g/${\ell}$ and 0.04 g/${\ell}$ respectively. Concentration of acetic acid and total phenolic compounds in SH were 1.4 g/${\ell}$ and 2.83 g/${\ell}$. Ethanol production using hydrolysate was 11.7 g/${\ell}$ at optimal pH 6.0 after 48 h. Specific ethanol production was 0.15 (g/(${\ell}^*h$)) at pH 5.0 and 5.5. while that was 0.24 (g/(${\ell}^*h$)) at pH 6.0. Specific ethanol production has difference depend on initial pH for fermentation. Ethanol production was 14.3 g/${\ell}$ after 48 h when xylanase 20 IU was added in SH for degradation of oligomer during fermentation. It implied that ethanol production increased by 22.2% compare with control (without xylanase).

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.946-950
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• 2014

Bacillus licheniformis was grown in minimal nutrient medium containing 1% (w/v) of distillers dried grain with soluble (DDGS), palm kernel meal (PKM), wheat bran (WB) or copra meal (CM), and the enzyme activity of endoglucanase, ${\beta}$-glucosidase, xylanase and reducing sugars was measured to investigate a possibility of using cost-effective agricultural residues in producing cellulolytic and hemicellulolytic enzymes. The CM gave the highest endoglucanase activity of 0.68 units/mL among added substrates at 48 h. CM yielded the highest titres of 0.58 units/ml of ${\beta}$-glucosidase, compared to 0.33, 0.23, and 0.16 units/mL by PKM, WB, and DDGS, respectively, at 72 h. Xylanase production was the highest (0.34 units/mL) when CM was added. The supernatant from fermentation of CM had the highest reducing sugars than other additional substrates at all intervals (0.10, 0.12, 0.10, and 0.11 mg/mL respectively). It is concluded that Bacillus licheniformis is capable of producing multiple cellulo- and hemicellololytic enzymes for bioethanol production using cost-effective agricultural residues, especially CM, as a sole nutrient source.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.257-263
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• 2003

The cellulases production in solid state fermentation (SSF) of Trichoderma harzianum FJ1 with high cellulases productivity using cellulosic wastes was investigated. Physical and chemical conditions of the fermentation, such as moisture content, initial pH, and composition of mixed substrate (wine waste, rice straw, and soybean flour) on FPase (Filter paper activity) production were examined. The enzyme production was optimized in the conditions of moisture content of 70%, pH 5.0, 3$0^{\circ}C$, and 1:1:1 composition of mixed substrate containing wine waste, rice straw, and soybean flour. The highest activities of FPA, CMCase, Xylanase, $\beta$-glucosidase, and Avicelase in the optimized culture conditions were 15.2, 69.1, 83.9, 29.2, and 4.2 unit/g-SDW in 5 day cultivation, respectively. Economical and efficient production of cellulolytic enzymes by T harzianum FJ1 using cellulosic wastes in solid state fermentation will contribute to the biological saccharification of cellulosic wastes with enormous potential resource value in future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1114-1121
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• 2017

Bacillus strains not producing harmful components were isolated from Korean traditional soybean products. Extracellular enzyme activities (amylase, protease, cellulase, and xylanase) of isolated Bacillus strains were measured, and Bacillus strains with high protease activity were selected. The selected 15 strains were identified as Bacillus amyloliquefaciens (10), Bacillus methylotrophicus (1), Bacillus velezensis (1), and Bacillus subtilis (3). Among them, B. subtilis JBG17019, B. amyloliquefaciens JBD17076, and B. amyloliquefaciens JBD17109 showed antimicrobial activities against food-borne microorganisms. The production abilities of glutamate, glutamine, and poly-${\gamma}$-glutamic acid (${\gamma}$-PGA) of the selected Bacillus strains were measured to analyze fermentation characteristics related to glutamic acid metabolism. The factor for multivariate was analyzed by the principal components analysis (PCA) method between fermentation characteristics and ${\gamma}$-PGA production. The three principal components were classified according to the PCA method: PC1 [enzyme activity (amylase, cellulase, and xylanase)], PC2 (${\gamma}$-PGA), and PC3 (protease, glutamate, and glutamine). As a result, B. amyloliquefaciens JBD17076 and B. subtilis JBG17019 strains were evaluated as having excellent enzyme activity and ${\gamma}$-PGA production.

• 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.