• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.549-555
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• 1993

The production of cellulase by Pseudomonas sp. LBC505 isolated was under the strict genetic and biochemical control mechanisms such as catabolit repression and induction. These biochemical control reduced cellulase production. Thus LBC505 was mutated to increase enzyme yields. Cells growth and cellulase production were inhibited by the addition of 2-deoxy glucose (2-DG), which is presumed to function as repressor for the selection of high cellulase yielding mutant.

• The Korean Journal of Mycology
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• v.12 no.2
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• pp.59-64
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• 1984

The effects of cultural conditions in the rice straw media for cellulolytic enzymes production by Pleurotus sajor-caju were investigated. The optimum moisture content, pH and temperature for enzymes production were 60%, 7.0 and $35^{\circ}C$ in $C_1-cellulase$, and 60%, 5.0 and $25^{\circ}C$ in $C_x-cellulase$, and 60%, 7.0 and $20^{\circ}C$ in ${\beta}-glucosidase$, respectively. When light was irradiated during the cultivation period, $C_1-cellulase$ and ${\beta}-glucosidase$ production were decreased but $C_x-cellulase$ production increased at $500{\sim}1,000\;lux$. During the cultivation period, $C_1-cellulase$ production was contrary to $C_x-cellulase$ and ${\beta}-glucosidase$. Among the various materials added, rice bran was effective to $C_1-cellulase$ production, cotton seed cake and rice bran to $C_x-cellulase$ production, and defatted soybean and fish meal to ${\beta}-glucosidase$ production. The optimum concentration of rice bran for enzymes production were 20% in $C_{1-}$, $C_x-cellulase$ and 10% in ${\beta}-glucosidase$.

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.44-49
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• 1999

Cellulase production by fed-batch cultivation of Trichoderma reesei Rut C30 with various initial concentrations of Solka Floc in 1 % wheat bran-containing medium was investigated. The cellulase activity and productivity increased with initial Solka Floc concentration up to 5%. When a total Solka Floc concentration of 90 g/l was used for cellulase production, CMC (carboxymethyl cellulose) and FP (filter paper) activities, productivity, and yield were 359.7 U/ml, 30.61 U/ml, 161 FPU $L^{-1}$ $h^{-1}$, and 340 FPU $g^{-1}$, respectively. It was important to maintain a high cell concentration during cellulase production to obtain high cellulase activity and productivity. Cellulase powder was prepared by ammonium sulfate precipitation: FP activity was 396.7 U/g and CMC activity was 6481 U/g.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.527-533
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• 1992

The optimal conditions for cellulase and xylanase production by Trichoderma reesei 28217 were studied for enzymatic deinking of old newspaper. The amounts of cellulase and xylanase from the strain was varied by initial medium pH, Tween 80, inoculum size of spore suspension, and carbon and nitrogen sources. The optimal conditions for cellulase production were pH 5.0-6.5, 0.02% of Tween 80, 0.5-1.0% of inoculum size of spore suspension ($1{\times}10^{7}$/ml). cottonseed meal as nitrogen source, and corn flour as carbon source. On the other hand, the optimal conditions for xylanase production were pH 6.5, 0.01% of Tween 80, corn steep liquor as nitrogen source, and disintegrated old newspaper as carbon source. The inoculum size for xylanase production was the same as for cellulase production. The concomitant production of cellulase and xylanase in shake flask culture was efficiently induced in the medium containing 0.5% cottonseed meal as nitrogen source and 1.0% old newspaper and 2.0% corn flour as carbon sources. In this case the activities of cellulase and xylanase produced were 6.11-7.22 IU/mJ and 97.7 IU/ml. respectively. However, the cellulase production in $5{\ell}$ fermentor scale was slightly decreased compared with that in flask scale. Moreover, xylanase production was severely reduced in a fermentor scale. The study for the reason of decreased enzyme production in fermentor is further needed.

• Journal of Microbiology and Biotechnology
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• v.8 no.3
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• pp.208-213
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• 1998

The effect of the addition of wheat bran to the growth medium on the production of cellulolytic enzymes of Trichoderma reesei Rut C30 was studied in batch culture using shake flasks. The activity of cellulase was enhanced by the addition of wheat bran to the cellulase production medium. $KH_2PO_4$-$K_2HPO_4$ buffer was used for pH control during cellulase production. As a result, high cellulase activities were obtained in shake flask culture; a CMC (carboxymethyl cellulose) activity of 125.78 U/ml was obtained from 2% Avicel- and 3% wheat bran-containing medium and an FP (filter paper) activity of 12.85U/ml was obtained from 1% Avicel- and 5% wheat bran-containing medium after 6 days of cultivation.

• KSBB Journal
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• v.25 no.2
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• pp.193-198
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• 2010

Cell cultures of Taxus wallichiana Zucc. were made to enhance the production of anticancer agent paclitaxel. In suspension cultures, the maximum cell growth rate in exponential growth phase was 0.14 $day^{-1}$ which was correlated to 4.96 days of cell doubling time. The production of paclitaxel was non-growth associated. The paclitaxel production was started after the exponential growth phase and increased to declined phase where the maximum concentration was observed. Various elicitors were tested to enhance the production of paclitaxel. The combination of two elicitors of jasmonic acid and cellulase increased the production of paclitaxel 1.8 and 3.1 times compared to paclitaxel production by individual elicitor respectively.

• Mycobiology
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• v.37 no.4
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• pp.267-271
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• 2009

A fungal strain producing a high level of cellulase was selected from 320 fungal isolates and identified as Aspergillus sp. This strain was further improved for cellulase production by sequential treatments by two repeated rounds of $\gamma$-irradiation of $Co^{60}$, ultraviolet treatment and four repeated rounds of treatment with N-methyl-N'-nitro-N-nitrosoguanidine. The best mutant strain, Aspergillus sp. XTG-4, was selected after screening and the activities of carboxymethyl cellulase, filter paper cellulase and $\beta$-glucosidase of the cellulase were improved by 2.03-, 3.20-, and 1.80-fold, respectively, when compared to the wild type strain. After being subcultured 19 times, the enzyme production of the mutant Aspergillus sp. XTG-4s was stable.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.149-154
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• 1996

Effects of various kinds of sawdusts, supplements and culture conditions on activities of several enzymes such as protease, phenoloxidase and cellulase produced from mycelium of P. ostreatus grown on sawdust medium were studied and the results are as follows; Higher specific activity of these enzymes was observed when oak tree sawdust and poplar tree sawdust were supplemented with rice bran or wheat bran at rate of 30%, 20% and 10% in total volume respectively. Higher total activities of protease, phenoloxidase and cellulase were observed at 70% of the moisture contents of culture media, while lower activity of these enzymes was observed with 40% moisture contents of sawdust culture medium. The pH 4 and 9 of the sawdust media appeared to be optimum pH for the. production of protease while pH 5 and 7 were optimal for the production of phenoloxidase. The pH 6 of the sawdust medium was optimal for the production of cellulase. The optimum incubating temperature for the production of protease, phenoloxidase and cellulase was $25^{\circ}C$. Higher total activities of protease and phenoloxidase were observed when culture medium was added with wood vinegar at the control, and 0.5% for cellulase.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.98-102
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• 2002

Lignocellulosic wastes available in abundance can be excellent substrates for the production of cellulase. Different types of substrates and various pretreatments were used to improve the production of cellulase. The steam-exploded wood chip gave the highest activities of FPase (0.84 IU/mL) and CMCase (6.5 IU/mL) in the shake-flask culture. In 30 L bioreactor the steam-exploded wood chip and residue after saccharification gave the FPase activity (0.72 IU/mL) and the CMCase activity (6.3 IU/mL), respectively, similar those obtained in lactose.

• Korean Journal of Microbiology
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• v.16 no.4
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• pp.141-147
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• 1978

In order to increase the productivity of cellulolytic enzymes, medium composition and culture conditions were studied. When cellulose powder (Avicel) supplemented with rice straw was used as carbon source, productivity of ${\beta}-glucosidase$ was increased by about 3 times compared with the runs with only cellulose powder as a carbon source. In this case no negative effects on the production of CMC enzyme activity and filter paper activity was found. For the production of celulolytic enzymes using T. reesei QM 9414, casitone was found to be a good nitrogen source compared with other sources studied, such as peptone, yeast extract, tryptone, and casein. The highest cellulase activity was attained when 0.3% glucose and 0.01% Tween 80 were supplemented to the standard medium of Rese. An adequate oxygen transfer rate was also found to be important to the cellulase fermentation and about 50 mmole of oxygen/liter/hour supported good cellulase biosynthesis during cellulase fermentation.