• Microbiology and Biotechnology Letters
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• v.17 no.1
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• pp.1-7
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• 1989

To enhance the capability of starch fermentation of the transformant TSD-14, the heat treated protoplasts of TSD-14 were fused with the protoplasts of C. tropicalis (lys$^-$) in the presence of 30% (w/ v) PEG and 20 mM CaC1$_2$. Fusants were selected by nutritional complementation on minium medium and the fusion frequency was 4.4$\times$10$^{-5}$. All fusants tested were possessed of complemented traits concerning carbon compound assimilation, and the cell volumes of the fusants were approximately 1.5 times larger than the parental strains. The fusants were genetically very stable, and were able to hydrolyze alpha 1,4-glucosidic linkage as well as alpha 1,6-linkage of starch contrary to one of parents TSD-14, The most promising fusant FSC-14-75 produced 8.7% (v/v) of ethanol from 15% liquefied potato starch medium, but the result was enhanced to 9.3% (v/v) by addition of 0.3% peptone. The corresponding fermentation efficiency was 86.0%.

• Applied Biological Chemistry
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• v.15 no.3
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• pp.199-206
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• 1972

As a study on the konjak mannan-hydrolyzing enzymes from Aspergillus awamori, the culture conditions for enzyme formation, purification and properties of the enzymes and the effect of gamma-irradiation on the enzymatic hydrolysis were investigated. The results are summarized as follows: 1) A strain of A. awamori was selected as having the highest productivity of mannanase among 81 species of molds. 2) The optimum conditions for solid culture on wheat bran were 3 days of culture period, pH 4 of spraying water and 100% addition of tap water. 3) The optimum conditions for shaking culture were 6 days of culture period, addition of 0.1% xylose plus 0.5% konjak mannan and of 0.04% peptone. 4) Konjak mannan-hydrolyzing enzymes were separated into fraction I and fraction II by ammonium sulfate fractionation and DEAE-Sephadex column chromatography. 5) Fractions I and II showed pH optima of 4, pH stability of $3.5{\sim}5$ and $3{\sim}6$ and the extent of hydrolyzing konjak mannan 9% and 50%, respectively. 6) Hydrolysis of konjak mannan by a crude enzyme preparation was partially accerelated by gamma-irradiation of substrate above 0.5 Mrad and the effect was more remarkable by irradiating in wet state than in dry state. 7) Gamma-irradiation of konjak mannan brought about the increase in reducing power and decrease in viscosity and the effect was more remarkable in wet state than in dry state.

• Journal of Applied Biological Chemistry
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• v.54 no.4
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• pp.252-257
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• 2011

To remove excess nitrate from the agricultural environments, Enterobacter amnigenus GG0461 has been isolated as a bacterial strain having high capability of nitrate uptake activity. This strain was able to remove nitrate more than 3,000 ppm (50 mM) in the Pseudomonas agar F (PAF) medium. Therefore, it could be a candidate strain for a nitrate scavenger in the various contaminated environments, such as agricultural soils, livestock sewage, and industrial wastewater. In order to develop medium for the large-scale production of the strain GG0461, each component of PAF medium was replaced with the corresponding commercial product and the optimal conditions for bacterial growth and nitrate uptake activity were measured. Glycerol was replaced with the commercially available product and the nitrogen source was substituted with commercial tryptone, yeast extract, soybean meal, and fermented fish extract. Bacterial growth and nitrate uptake activity were maximal in the media containing 2% tryptone, followed by yeast extract, soybean meal, and fermented fish extract. The pH of the growth medium containing 2% tryptone was decreased by the bacterial nitrate uptake, suggesting that the nitrate uptake is mediated by a nitrate/proton antiporter. This result shows that the medium containing commercial tryptone was good enough for the physiological activity of the strain GG0461. Each component of PAF medium was successfully replaced with the corresponding commercial product except peptone. In conclusion, the composition of medium for the cultivation of the strain GG0461 was determined as 2% tryptone, 1% glycerol, plus required salts according to the composition of PAF medium.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.59-66
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• 1983

Cultural conditions for the production of extracellar $\beta$-galactosidase by Loctobacillus sporogenes, a spore forming lactic acid bacterium, were investigated with shaken flask and jar fermenter cultures. The fermentation medium giving maximum $\beta$-galactosidase yield was found to consist of 1 % lactose as a carbon source, 1.5% peptone as an organic nitrogen source. 0.2% ammonium sulfate as an inorganic nitrogen source, 0.8% ammonium phosphate dibasic as a phosphorus source, and 0.05% potassium chloride and 0.001% ferric chloride as mineral source. Optimal initial pH of the medium was 7.0 and the highest enzyme excretion was observed after 40 hours of cultivation at 37$^{\circ}C$. In this experiment, the 500$m\ell$ conical flask containing 50-200$m\ell$ of medium was shaken at 140 strokes per minute with 7cm amplitude in a reciprocating shaker. The maximum enzyme value attained was 38 U/$m\ell$ of the culture broth which was found to be slightly higher than the highest intermolecular enzyme activity (30 U/$m\ell$) observed after 24 hours of incubation. In the fermentor culture, the fermentation profile was shown to be similar to that observed in the shaken flask experiment. But the maximum extracellular enzyme activity was 45 U/$m\ell$ to be even higher than the value obtained with the shaken flask culture.

• 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.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.145-152
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• 1994

In order to investigate the cultural characteristics of Lentinus lepideus, media, pH, carbon sources, nitrogen sources, vitamin and organic acids were tested in submerged culture. It grew well in GPB(broth), and the optimum temperature and pH was $25^{\circ}C$ and 4.2, respectively. The carbon sources such as galactose belong to monosaccharide and maltose belong to disaccharide were effective for mycelial growth. Peptone which is compound nitrogen source was good for mycelial yield but the other nitrogen sources were not effective. Among the various vitamins, pyridoxine is suitable for mycelial yield. Among the various organic acids, citric acid promoted the mycelial yield but acetic acid interrupted the mycelial growth of L. lepideus.

• The Korean Journal of Mycology
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• v.15 no.2
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• pp.99-170
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• 1987

The production and properties of laccase(E.C.1.10.3.2) from Coriolus versicolor were studied. The results were as follows; The nutritional optimum conditions for laccase production were 1% indulin At, 0.3% peptone 0.1% $KH_2PO_4$, 0.02% $MgSO_4$, 0.1 mg% $CuSO_4$.and 0.005 mg% thiamine HCI. The optimum temperature and pH of laccase production were $25^{\circ}C$ and 5.0, and respectively, and the cultural period was 20 days. The optimum pH and temperature for the activity were 4.6 and $40^{\circ}C$, respectively. The enzyme was almost stable under the temperature of $40^{\circ}C$ and within the pH range of 4.0-5.0. The enzyme was stable at $40^{\circ}C$ for 30 min. $Cu^{++}$, $Fe^{++}$ and $Ca^{++}$ activated the enzyme activity, but $Mn^{++}$ and $Hg^{++}$ were inhibited. The enzyme was totally inhibited by 1 mM sodium azide and 1 mM potassium cyanide, and partly inhibited by EDTA and hydroxyamine.

• The Korean Journal of Mycology
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• v.45 no.4
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• pp.336-344
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• 2017

The anti-inflammatory effects of cell-free extracts from wild yeasts, Meyerozyma guilliermondii YJ34-2 and Rhodotorula graminis YJ36-1, caused by the inhibition of nitric oxide (NO) activity and cytotoxic effects were determined. Cell-free extracts from these two yeast strains had dose-dependent inhibitory effects on the production of lipopolysaccharide-induced NO and there were no cytotoxic effects on the treated cells or negative effects on their proliferation. Their cell-free extracts were also shown to have inhibitory effects on pro-inflammatory cytokines, such as tumor necrosis factor $(TNF)-{\alpha}$ and $prostaglandin-E_2$, in a dose-dependent manner. Maximal inhibitory activity on NO production occurred in cell-free extracts of Meyerozyma guilliermondii YJ34-2 cultivated at $30^{\circ}C$ for 24 hr and Rhodotorula graminis YJ36-1 cultivated at $25^{\circ}C$ for 24 hr in the yeast extract-peptone-dextrose (YPD) media.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.395-402
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• 2001

A fusant FG-21 was selected on the basis of higher ${\gamma}-GTP$ activity following fusion process between SM-2 and SM-10 of Bacillus subtilis mutants. ${\gamma}-GTP$ activity of the mutant FG-21 was increased up to 612 U/mL when grown for 36 hr at $37^{\circ}C$ in culture media containing 1% glycerol 1% glycerol, 1% peptone, 0.1% citric acid, 5 mM $K_2HPO_4$, 1 mM $FeCl_3$, 1 mM $MgCl_2$, 1 mM $NH_4Cl$, pH 7.0. In fusnat FG-21, the ratio of protein to total sugar contents for biopolymer A was 38 to 59. for biopolymer B from parental strains it was 19 to 78. Fructose contents determined by HPLC were $573.7\;\mu\textrm{g}/mg\;and\;764.4\;\mu\textrm{g}/mg$ for biopolymer A and B, respectively. And glutamic acid content were $163.7\;\mu\textrm{g}/mg\;and\;94.6\;\mu\textrm{g}/mg$ for biopolymer A and B, respectively. In fusant FG-21, the ratio of fructose to glutamic acid contents for biopolymer A was 78 to 22. For biopolymer B from parental strains it was 89 to 11.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.915-921
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• 1996

An alkaline pretense Producing microorganism was isolated from Korean traditional soy sauce and identified as Bacillus subtilis CCKS-111. The optimum culture condition of Bacillus subtilis CCKS-111 for the production of alkaline pretense was as follow: 2% soluble starch, 0.2% peptone, 0.1% (NB$_4$)$_2$S$_2$O$_{8}$ , 0.2% MgSO$_4$, pH 7.0, 35$^{\circ}C$ and 24hrs. The optimum pH and temperature for the enzyme activity of alkaline pretense producing Bacillus subtilis CCKS-111 were pH 9.0 and 5$0^{\circ}C$, respectively. The enzyme was relatively stable at pH 6.0~11.0 and at temperature below 4$0^{\circ}C$. The activity of the enzyme was inhibited by $K^{+}$ and Hg$^{2+}$, whereas Cu$^{2+}$ exhibited rather activating effects on the enzyme activity. Ethylenediaminetetraacetic acid and phenylmethanesulfonyl fluoride inhibited the enzyme activity. This indicates that this is serine pretense which requires metal ion group for the enzyme activity. Km value was 2.313$\times$10$^{-4}$ M/L, V$_{max}$ value was 39.216$\mu\textrm{g}$/min. This enzyme hydrolyzed casein more rapidly than the hemoglobin.lobin.