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

• Journal of the Korean Wood Science and Technology
• /
• v.47 no.6
• /
• pp.751-760
• /
• 2019

Cellulase is an eco-friendly biocatalyst, and its demand is growing in many industrial applications such as food, textile, paper, and bioenergy. Strains with a high cellulase activities are the starting point for the economic production of cellulase. In a previous study, Acanthophysium sp. KMF001 with high cellulase production ability was selected among 54 wood-rotting fungi. In this study, we evaluated the cellulase productivity of Acanthophysium sp. KMF001 quantitatively and analyzed its taxonomic location using a genetic method. Acanthophysium sp. KMF001 showed high cellulase productivity similar to that of Acanthophysium bisporum and was much better than A. bisporum in specific enzyme activity. The 28S rRNA sequence of Acanthophysium sp. KMF001 was similar to that of Acanthophysium lividocaeruleum MB1825, with 98.40% homology. Phylogenetic analysis suggested that Acanthophysium sp. KMF001 is a new strain. In this study, we propose a new strain with high cellulase productivity.

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

• Journal of Microbiology and Biotechnology
• /
• v.8 no.6
• /
• pp.575-580
• /
• 1998

Cellulase production by batch culture using the Trichoderma reesei Rut C30 strain with various concentrations of Solka Floc with 1 % wheat bran was studied in a 2.5 I fermenter. The cellulase activity increased with Solka Floc concentration up to 5%. When 5% Solka Floc and 1% wheat bran were contained in the medium, carboxymethyl cellulose (CMC) and filter paper (FP) activities were 232.4 U/$m\ell$ and 21.25 U/$m\ell$, respectively. The productivity was 143.6 FPU $1^{-l}h^{-1}$ and the yield was 425 FPU/g. The colonial morphology of T. reesei Rut C30 grown on Avicel agar plates and the changes in mycelial morphology of T. reesei Rut C30 with culture time are also presented.

• Microbiology and Biotechnology Letters
• /
• v.25 no.6
• /
• pp.546-551
• /
• 1997

A bacterium producing the extracellular cellulases was isolated from soil and has been identified as Bacillus sp. The isolate, named Bacillus sp. 79-23, was shown to be very similar to B. subtilis on the basis of its biochemical properties. The carboxymethyl cellulase (CMCase) of culture supernatant was most active at 60$\circ$C and pH 6.0, and retained 90% of its maximum activity at pH 7.0. The additional carbon sources affected the CMCase productivity than nitrogen sources in the culture medium. The carbon sources including wheat bran, rice straw, maltose and glucose increased the enzyme productivty. Especially, the maximum CMCase production was 5.2 units/ml in LB medium supplemented with 3% (w/v) wheat bran, which was 13-folds more than that in LB medium. It was found that the enzyme production was in association with the growth of Bacillius sp. 79-23. But, whean bran did not affect the growth of isolate, suggesting that increasement of CMCase production was owing to the induction of CMCase biosynthesis by wheat bran. In addition, both water-soluble and insoluble components of wheat bran was involved in induction of CMCase biosynthesis.

• Proceedings of the Korean Society for Applied Microbiology Conference
• /
• 1979.04a
• /
• pp.115.2-115
• /
• 1979

By employing a two-stage continuous culture system, some of important physiological parameters involved in cellulase bicsynthesis have been evalua-ted with an ultimate objective of detigning an op-timally controlled tellulase process. Volumetric and specific cellulase productivities obtained were 90 IU/liter/hr and 8IU/g biomass/hr respectively. The maximum specific enzyme productivity observed was 14.8 IU/g hiomass/hr. The optimal dilution rate in the second stage which corresponded to the maximum enzyme productivity was 0.026-0.028 hr$^{-1}$ , and the specific growth rate in the second stage ihat suported maximum specific enzyme productivity was equal to orslightly less than zero. The maintenance coefficients deter-mined for oxygen and for carbon source are M$_{o}$=0.85mmmole/g biomass/hr and M$_{c}$=0.14 mmole hexose/g bio mass/hr respectively. The yield constants determined are; Y(x/o) =32.3g biomass/mole oxygen, Y (x/c) =1.1g bio-mass/g carbon or 0.44g biomass/g hexose, Y(x/n) = 19.6g biomass/g nitrogen for the enzyme produc-tion stage and 12.5g biomass/g nitrogen for the cell growth stage.e.e.

• The Korean Journal of Mycology
• /
• v.40 no.3
• /
• pp.152-158
• /
• 2012

The lignocellulytic enzymes including a-amylase (EC 3.2.1.1), lignin peroxidase (EC 1.11.1.14), laccase (EC 1.10.3.2), xylanase (EC 3.2.1.8), ${\beta}$-xylosidase (EC 3.2.1.37), ${\beta}$-glucosidase (EC 3.2.1.21) and cellulase (EC 3.2.1.4) were extracted from spent mushroom compost (SMC) of Pleurotus eryngii. Different extraction buffers and conditions were tested for optimal recovery of the enzymes. The optimum extraction was shaking incubation (200 rpm) for 2 h at $4^{\circ}C$. ${\alpha}$-Amylase was extracted with the productivity range from 1.20 to 1.6 Unit/SMC g. Cellulase was recovered with the productivity range from 2.10 to 2.80 U/gf. ${\beta}$-glucosidase and ${\beta}$-xylosidase productivities showed lowest recovery producing 0.1 U/g and 0.02 U/g, respectively. The P. eryngii SMCs collected from three different mushroom farms showed different recovery on laccase and xylanse, cellulase. Furthermore, the water extracted SMC was compared to commercial enzymes for its industrial application in decolorization and cellulase activity.

• Journal of Microbiology and Biotechnology
• /
• v.11 no.2
• /
• pp.229-233
• /
• 2001

Trichoderma reesei Rut C-30 produced high levels of ${\beta}$-glucosidase, endo-${\beta}$-glucosidase, endo-${\beta}$-1,4-glucanase, and exo-${\beta}$-1,4-glucanase. In pilot-scale production (50-1 fermentor), productivity and yield of CMCase (carborymethyl cellulose) and FPase (filter paper activity) were 273 U/ml and 35 U/ml, and 162 FPU/l.h and 437 FPU/g, respectively. The fed-batch techniques were used to improve enzyme activities with constant cell concentration. The acidity was an important parameter and controlled at pH 3.9 and 5.0 by automatic addition of ammonium hydroxide. Cellulase powder was prepared by ammonium sulfate precipitation and its CMCase and FPase activities were 3,631 U/g and 407 U/g, respectively.

• Microbiology and Biotechnology Letters
• /
• v.16 no.3
• /
• pp.182-186
• /
• 1988

The possibility of strain improvement of cellulolytic fungus, Penicillium verruculosum via protoplast fusion was investigated. The cellulolytic activities of the six fusants, finally selected for their hyper-cellulolytics were 2 times of those of wild type and 1.2 to 4.4 times of those parental auxotrophs. It was confirmed that the nuclear fusion occurred in fusants by their DNA contents and nuclear staining with Giemsa. It was also found that the fusants were aneuploids, and their genetic stability was demonstrated from the subculture for four months.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.7
• /
• pp.1101-1107
• /
• 2015

The role of CRE1 in a thermophilic fungus, Myceliophthora thermophila ATCC42464, was studied using RNA interference. In the cre1-silenced strain C88, the filter paper hydrolyzing activity and β-1,4-endoglucanase activity were 3.76-, and 1.31-fold higher, respectively, than those in the parental strain when the strains were cultured in inducing medium for 6 days. The activities of β-1,4-exoglucanase and cellobiase were 2.64-, and 5.59-fold higher, respectively, than those in the parental strain when the strains were cultured for 5 days. Quantitative reverse-transcription polymerase chain reaction showed that the gene expression of egl3, cbh1, and cbh2 was significantly increased in transformant C88 compared with the wild-type strain. Therefore, our findings suggest the feasibility of improving cellulase production by modifying the regulator expression, and an attractive approach to increasing the total cellulase productivity in thermophilic fungi.