• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.505-510
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• 1992

An endo-$\beta$-1,4-glucanase gene of Clostridium thermocellum was cloned in Escherichia coli and was considered as a novel gene by comparison with the restriction patterns of the C. thermocellum cellulase genes so far reported. The endoglucanase from recombinant E. coli was purified by column chromatography after heat treatment. The purified enzyme was a monomer having molecular weight of 40,000. The enzyme hydrolyzed CMC to glucose and cello-oligosaccharides at :naximum activities at pH 5.0 and $65^{\circ}C$. One of the endproducts, glucose, showed no inhibitory effect on the enzyme activity, while the other endproduct, cellobiose, inhibited slightly. The values of $K_{m}$ and $V_{max}$ of the enzyme for CMC were 0.39% (w/v) and 268 Ulmg protein, respectively.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.239-245
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• 1998

The feasibility of enzymatic hydrolysis of cellulosic materials is dependent on the cost of cellulase, which is strongly influenced by the selection of proper carbon source in the cellulase production medium. When solka floc was used as a carbon source for the production of cellulase by Trichoderma reesei Rut C-30, a maximum of 53.2 U/ml of CMCase activity (4.8 U/ml of FPase activity) was obtained with a concentration of 1 % of solka floc. The cellulase activity decreased to 50% in the presence of 0.5% of glucose in the medium. The production of cellulase was considerably enhanced when solka floc and wheat bran were used together as a carbon source. A medium which contained 1 % of solka floc and 3 % of wheat bran yielded highest cellulase activity: CMCase activity of 76 U/ml and FPase activity of 12.5 U/ml.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.91-95
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• 1998

Cellulase producing microorganisms, GPC-1, GPC-2, GNR-1 GNR-2, and GNR-3, were screened from the Rumen fluid of Korean Native Cattle. Isolated GPC-1 and GPC-2 were identified as Ruminococcus sp. according to results of the Gram stain and anaerobic characteristics. Based on morphological and physicochemical identification, the isolate GPC-1 and GPC-2 were identified as strains of Ruminococcus albus and Ruminococcus flavefaciens, respectively. Isolated GNR-1 GNR-2 and GNR-3 were identified as Bacteroides sp., Butyrivibrio sp. and Clostridium sp. according to results of the Gram stain, $H_2S$ producition and spore formation, respectively. Based on morphological and physicochemical identification, the isolate GNR-1 GNR-2 and GNR-3 were identified as strains of Bacteroides succinogenes, Butyrivibrio fibrisolvens and Clostridium cellobioparum, respectively.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.04a
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• pp.184.6-184
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• 1976

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.167-172
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• 1977

Colony morphology, growth responses on some simple carbon sources and taxonomic position were established for three stock cultures of National Collection of Industrial Bacteria, Scotland. It was confirmed that NCIB 8077 belonged to the Cellulomonas species and that NCIB 8633 and NCIB 8634 belonged to the Pseudomonas species. Taxonomy of other cellulolytic bacteria published on various journals was also discussed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.35-43
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• 2017

This study was to research the relationships between rice straw degradation and changes of fibrolytic bacteria population during the in vitro rumen fermentation. Dry matter(DM) digestion of rice straw and population of fibrolytic bacteria were measured at the 0. 4, 8, 12 and 48 hours during the incubation. The populations of F. succinogenes. R. albus and R. flavefaciens were defined as log copy number of 16S rDNA by technical method of Quantitative real-time PCR. Total population of F. succinogenes, R. flavefaciens and R. albus was sum of bactera attached on rice straw and suspended in medium. It's population was increased with incubation, reached top level of 29.0 Log copy No at the 24 hour and then decreased. In the meantime, DM digestion of rice straw showed the higher increasement from the 8 hour to the 24 hour than from the 0 hour to the 8 hour, and then a slowdown in increasing trend of digestibility. Attachments of F. succinogenes, R. flavefaciens and R. albus were detected immediately after start of in vitro rumen incubation. At the same time, the colonized bacterial share were respectively 34.5%, 84.4% and 67.9% in total population. All of them was reached the highest colonized bacterial share above 94.7% at the 4 hour incubation. However population of attached bacteria was shown the highest level at the 12 hour or the 24 hour incubation. Kinetics of colonization were formed area of top speed from the 12 hour to the 24 hour and respectively reached 10.33, 9.28 및 8.30 Log copy No/h/g DM at the 24 hour by F. succinogenes, R. flavefaciens and R. albus. The kinetics of rice straw degradation was formed top level of 0.95% DM/h at the 24 hour. The present results gave clear evidence that degradation of rice straw was increased with the development of total fibrolytic bacteria in process of rumen fermentation. Also, their attachment was largely occurred immediately after insertion of rice straw, the colonized bacteria was actively proliferated, and then degradation of rice straw was maximized.

• The Korean Journal of Mycology
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• v.43 no.4
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• pp.239-246
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• 2015

Two fungal strains were isolated from rods of Quercus sp. (NAAS02335) and Pinus densiflora (NAAS05299) in Korea. These strains were identified as Gyrodontium sacchari by their morphological and mycological characteristics. The optimal growth temperature of NAAS02335 and NAAS05299 are $25^{\circ}C$ and $30^{\circ}C$, respectively. Production of cellulase, xylanase, and ligninase was tested on agar media supplemented dyes or substrates. Production of cellulase and xylanase of NAAS05299 was higher than those of NAAS02335, however ligninase activity of NAAS02335 was higher than that of NAAS05299. The activities of cellulase, xylanase, and amylase of strain NAAS05299 were estimated at 6.7~10.2 times higher than that of NAAS02335. Laccase activity was only estimated by strain NAAS02335. The lignocellulytic enzymes are induced by substrates such as rice straw, wooden chips of pine, oak, and poplar. The NAAS05299 was able to degrade filter paper completely after 4 weeks of culturing in liquid media containing a piece of filter paper at $28^{\circ}C$ with continuous shaking. NAAS05299 was able to degrade rice straw, pine chips, and oak chips after 4 months in solid culture, however NAAS02335 decomposed only rice straw among tested 4 kinds of biomass.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.209-220
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• 2015

In this study, gut bacterial communities in xylophagous insects were analyzed using the pyrosequencing of 16S rRNA genes for their potential biotechnological applications in lignocelluloses degradation. The result showed that operational taxonomic units (OTUs), species richness and diversity index were higher in the hindgut than in the midgut of all insect samples analyzed. The dominant phyla or classes were Firmicutes (54.0%), Bacteroidetes (14.5%), ${\gamma}-Proteobacteria$ (12.3%) in all xylophagous insects except for Rhinotermitidae. The principal coordinates analysis (PCoA) showed that the bacterial community structure mostly clustered according to phylogeny of hosts rather than their habitats. In our study, the two carboxymethyl cellulose (CMC)-degrading isolates which showed the highest enzyme activity were most closely related to Bacillus toyonensis $BCT-7112^T$ and Lactococcus lactis subsp. hordniae $NCDO\;2181^T$, respectively. Cellulolytic enzyme activity analysis showed that ${\beta}-1,4-glucosidase$, ${\beta}-1,4-endoglucanase$ and ${\beta}-1,4-xylanase$ were higher in the hindgut of Cerambycidae. The results demonstrate that xylophagous insect guts harbor diverse gut bacteria, including valuable cellulolytic bacteria, which could be used for various biotechnological applications.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.60-67
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• 2014

The comparisons between cellulolytic bacteria adhesion on rice straw and fiber digestion in time course during rumen fermentation were studied in situ. The adhesions of cellulolytic bacteria, F. succinogenes. R. albus and R. flavefaciens, were measured by RT-PCR. When the rice straws were incubated at 0. 2, 4, 8, 12 and 24 hours of the in situ rumen, straw was degraded with increasing speed during the incubation and showed the highest disappearance increasing rate (DM g/h) from 8 to 12 hour. The adhesions of F. succinogenes, R. flavefaciens and R. albus were achieved above 80% in 1 hour of in situ rumen fermentation and then keep adhesive population up after the time of fermentation. When the in situ samples were collected at 0, 5, 10, 30 and 60 min to detect the early stages of adhesion on the rice straws ingested into rumen, the numberous adhesive colony of F. succinogenes, R. flavefaciens and R. albus were detected in 5 min. In case of rice straw treated with 0, 2, 4 and 8% NaOH, all of three cellulolytic bacteria showed the increasing trends of adhesion with increasing DM disappearance of rice straw by higher concentration of NaOH at 12 hour of in situ. However, there were showed respectively difference at 24 hour. The present results gave certain evidence that adhesion of cellulolytic bacteria is definitely achieved in early stage of roughage ingestion into rumen, their colony develop the stable communities on roughage in process of rumen fermentation and then fiber degradation is accelerated.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.172-176
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• 2002

A filamentous microorganism, strain FJ1, was isolated from completely rotten wood for the production of cellulolytic enzymes. For the production of the enzymes, cellulolsic wastes were used as carbon sources of strain FJ1 and rice straw showed higher enzyme activities than sawdust and pulp. The activities of CMCase, xylanase, $\beta$-glucosidase, and avicelase were 2.95, 5.89, 0.45, and 0.12 unit/ml by use of rice straw, respectively. To enhance production of the enzymes, the mixture substrate of rice straw and cellulosic materials were investigated as carbon sources. The highest activities of CMCase, $\beta$-glucosidase, and avicelase were found in the mixture of rice straw (0.5%, w/v) and avicel (0.5%, w/v), and the highest xylanase was obtained at the mixture ratio of 0.71%(w/v) and 0.29%(w/v). Addition of 0.1%(w/v) peptone showed enhanced production of the cellulolytic enzymes in which the activities of CMCase, xylanase, $\beta$-glucosidase, and avicelase were 19.23, 27.18, 1.28, and 0.53 unit/ml, respectively. The production of the enzymes using rice straw was efficiently induced in the presence of avicel and pulp containing cellulose. In particular, a medium composed of rice straw (0.5%, w/v) and pulp (0.5%, w/v) yielded larger cellulolytic enzymes: CMCase 24.3 unit/ml, xylanase 38.7 unit/ml, $\beta$-glucosidase 1.5 unit/ml, and avicelase 0.6 unit/ml. The filamentous microorganism, strain FJ1 utilized various cellulosic wastes as carbon sources and will be expected as a favorable candidate for biological saccharification of cellulosic wastes.