• KSBB Journal
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• v.8 no.4
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• pp.409-414
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• 1993

This study was designed to reveal the conditions for $\beta$-glucosidase production from Aspergillus niger. The maximal enzyme production was obtained when the fungus was cultured at $30^{\circ}C$ for 5~6 days in the optimal medium containing 0.8% CMC, 0.5% beef extract, 0.3% Ca(NO3)2, 0.03% K2HPO4, 0.03% FeSO4, 0.05% Li2SO4, 0.2% tween 80, trace solution 1.0ml and initial pH 4.0, and then final enzyme activity under above conditions was 8.5-9.8 unit/ml culture filtrate.

• Korean Journal of Microbiology
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• v.21 no.4
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• pp.213-220
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• 1983

Conditions for isolation of protoplasts from conidiospores of Trichoderma koningii ATCC 26113 were tested. Maximum production of conidial protoplasts was obtained by preincubation of conidiospores on liquid minimal medium for 8 1/2 hrs. and by reaction with cell wall lytic enzyme for 3 hrs. Among effective cell wall lytic enzymes (Driselase, p-Glucuronidase, Novozyme and Zymolyase), Driselase was the most effective one on the production of conidial protoplasts. The production of conidial protoplasts was also enhanced by addition of 2-Deoxy-D-Glucose $(25{\mu}g/ml)$ into liquid minimal medium. Over 70% of the initial swollen conidia, preincubated in liquid minimal medium supplemented with 2-Deoxy-D-Glucose $(25{\mu}g/ml)$, were converted to protoplasts by incubation with 2% (w/v) commercial lytic enzyme Driselase at $28^{\circ}C$ for 3 hrs. The reversion frequency of the conidial protoplasts was about 30 times (25-50%) higher than that of mycelial protoplasts (0.6-1.3%).

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.277-285
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• 1997

Kluyveromyces marxianus var. marxianus isolated as an inulin-assimilating microorganism produces inulin fructotransferase (inulaseII) which catalyses the conversion of inulin into di-D-fructofuranose 1, 2' : 2, 3' dianhydrde (DFAIII). The DFA produced by the organism was isolated by using active carbon column, and identified as DFAIII by high performance liguid chromatography. The culture medium giving maximum inulaseII production was found to consist of 1% sucrose and 0.75% yeast nitrogen base (YNB). The inulasell production was induced by inulin or sucrose as a carbon source and increased by addition of YNB as a nitrogen source. Optimal initial pH of the culture medium, culture temperature and medium volume for the enzyme production were pH 4.7, 30$\circ$C and 140 ml, respectively. Under the optimal conditions described above, the enzyme activity in the culture supematant reached 4.2 units/ml after cultivation for 36 h. The DFAIII was accumulated at 13.25 mg/ml after 48 h of culture in the Jerusalem artichoke tuber medium.

• Food Science and Industry
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• v.53 no.1
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• pp.43-55
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• 2020

Most reports demonstrated the substrate specificity-based kinetic properties of chitin or chitosan degrading enzymes. However, there is virtually less information on the high quality and quantity production of chitin or chitosan hydrolysates having a larger than (GlcN)₇ from the hydrolysis of high molecular weight chitosan using specific enzymes and their biological activity. Therefore, the production of such molecules and the discovery of such enzyme sources are very important. Fortunately, the author has established a mass production method of chitosan hydrolysates (GlcN)_n, n=2-13 that have been characterized as a potent antioxidant substance, as well as antifungal and antibacterial activities against Penicillium species and highly selective pathogenic bacteria. In addition, preclinical studies using (GlcN)_n, n=5-25 demonstrated that these molecules played a very important role in maintaining biometric balance. Collectively, it is implicated that the application of these mixed substances to foods with significant biological activity is very encouraging.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.131-142
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• 2003

We evaluated the effects of adding fibrolytic enzyme into ruminant diets on ruminal fermentation (in vitro) and lactational performances of dairy cows (in vivo). Through the in vitro experiment that was carried out with different contents of NDF (34, 38, 43%) in diets, digestibilities of NDF in the rumen appeared not significantly different by the addition of enzyme but were different by NDF content in diets showing higher digestibility in NDF 43% diet. It could be attributed by the relatively higher amount of hemicellulose in the current experimental diets than in conventional diets that might have been digested easily by the addition of fibrolytic enzyme in the rumen. The addition of fibrolytic enzyme tended to increase NDF digestibilities to a little extent both in 0.05 and 0.1% enzyme levels. Ruminal pH, NH3-N concentrations and VFA production in the rumen were not affected by the addition of fibrolytic enzyme. Activities of CMCase and xylanase were higher in enzyme treated diets of both NDF 34 and 38%. In particular, the activities of xylanase that slowly decreased from 0 to 12 hr but rapidly after 24 hr indicates that the major action of the enzyme in the rumen occurs in early period of incubation. Through an in vivo experiment, fibrolytic enzyme addition into the diets of dairy cows indeed affected lactational performance of milk yield. The cows fed enzyme treated diets produced 8% (1.9kg/d) more amounts of milk than with no enzyme addition. Milk composition of milk fat and protein was not affected by enzyme addition. Overall, the results of this in vivo study indicates that fibrolytic enzyme can be used to improve milk production in lactating cows. In respect that animals in different treatments of this study had the same amounts of intake, the increased milk yield with enzyme addition may be attributed to the improved utilization of nutrients in the digestive tract.

• Korean Journal of Microbiology
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• v.34 no.1_2
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• pp.20-25
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• 1998

To obtain higher yield of 2,3-dihydroxybiphenyl(2,3-DHBP) dioxygenase by recombinant E. coli CK1092 carrying pcbC gene of Pseudomonas sp. P20, the environmental and physiological factors were investigated and the cultural conditions using jar fermentor were studied. E. coli CKl092 was grown in LB medium supplemented with 2% sucrose, as a basal medium. The effect of various metal ions on the enzyme production was investigated. In particular, the enzyme production increased in the presence of $Fe^{3+}$ and $Fe^{2+}$, and showed the maxium at the concentration of $10^{-5}M$. The enzyme production was increased by 55% in the medium containing $Fe^{3+}$ ($10^{-5}M$) ion. The optimal temperature and initial pH for cell growth were $37^{\circ}C$ and 7.0, respectively. In the culture using a fermentor at $37^{\circ}C$, the optimal conditions for the enzyme production were obtained at the initial pH 7.0, 1 v/v/m of aeration rate, 200 rpm of agitation speed. It was found that enzyme activity was higher when cultivated without pH control than with pH control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.3
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• pp.138-146
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• 1989

This experiment was conducted to utilize the water soluble protein from the fish meal in wastewater as nitrogen source by alkaline protease producting bacteria and to investigate the culture condition of the production. G-12 and G-14 strains having the strong activity of the alkaline pretense were isolated from sea water. These strains were identified as Pseudomonas chlororaphis and Pseudomonas alcaligenes according to physiologycal characteristics, respectively. In enzyme production, galactose and casein for G-12 strain, and raffinose and the water soluble protein of the fish meal wastewater for G-14 strain was favorable as carbon and nitrogen source. An action of inhibition appeared in all of the metal salts used. The optimal temperature of enzyme production was $30^{\circ}C$ for all strains. Optimal initial pH for the enzyme formation in G-12 and G-14 strains was pH 10.0 and 8.0. When these two strains were incubated for $30\~35$ hours in the optimal production medium, the enzyme production reached at maximum.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.145-154
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• 1982

To maximize the production of glucose oxidase by Aspergillus niger KUF-04 isolated from a soil, the cultivation conditions and nutrient sources for the enzyme production were studied. The results obtained were as fellows: 1. The optimum temperature, pH of the medium, and cultivation time for the enzyme formation were found to be 28-34$^{\circ}C$, 7.0-8.0 and 40 hours, respectively. 2. The best carbon source was proved to be glucose and its most effective concentration was 15 percent. 3. Ammonium sulfate was the best nitrogen source as compared with the other inorganic and organic nitrogen sources tested. Its optimum concentration for the glucose oxidase production was 0.02 percent. 4. As mineral sources, 0.05% of Mag cesium sulfate 7-hydrate and 0.02% of Potassium phosphate, monobasic seemed to be necessary to further increase the level of the enzyme production.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.449-452
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• 2002

A filamentous microorganism was isolated from completely rotten wood for the production of cellulolytic enzyme. The Trichoderma sp. FJ1 produced a large amount of cellulolytic enzymes, such as CMC, xylanase, ${\beta}-glucosidase$, and avicelase. For the production of the enzymes, when cellulolsic wastes were used as carbon sources of strain FJ1, rice straw showed higher enzyme activities than sawdust and pulp. The activities of CMC, xylanase, ${\beta}-glucosidase$, and avicelase were 2.95, 5.89, 0.45, and 0.12 U/ml in use of rice straw, respectively. To enhance production of the enzymes, the mixture substrate of rice straw and commercial cellulosic materials was investigated as carbon sources. The highest activities of CMCase, ${\beta}-glucosidase$, and avicelase were found in the mixture of rice straw and avicel, particularly rice straw:avicel (50:50), and the highest xylanase was obtained in the mixture ratio of 71:29. Bacto peptone addition of 0.1% 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 U/ml, respectively. The production of the enzymes using rice straw was efficiently induced in present of avicel and pulp containing high content of cellulose. Consequently, the filamentous microorganism, strain FJ1 utilized various cellulosic wastes as carbon sources and cellulases productivities were excellent compared to those of others strains reported previously, suggesting that the strain FJ1 will be expected as a favorable candidate for biological saccharification of cellulosic wastes in further.

• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.228-234
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• 2006

The culture conditions were investigated to maximize the production of laccase from Fomitella fraxinea mycelia. Among the tested media, mushroom complete medium (MCM) showed the highest production of the enzyme. The optimum culture medium was 2% dextrose, 0.4% $(NH_4)_{2}HPO_4$, 0.05% $Na_{2}HPO_{4}{\cdot}7H_{2}O$, and 0.05% KCl as carbon, nitrogen, phosphorus, and inorganic salt sources respectively. SDS-PAGE followed by laccase activity staining using 2,6-djmethoxyphenol as the substrate was performed to identify the laccase activity under culture conditions studied. Zymogram analysis of the culture supernatant showed a laccase band with a molecular mass of 50 kDa. The enzyme production from F. fraxinea was reached to the highest level after the cultivation for 10 days at $25^{\circ}C$ and initial pH 8. The enzyme activity of the culture supernatant was most active at $50^{\circ}C$ and pH 5.