• Korean Journal of Microbiology
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• v.18 no.2
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• pp.51-58
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• 1980

Mutational experiments were performed to improved to improve the protease productivity of Aspergillus flavus KU 153, which is selected among the wild strains. A UV-induced mutant strain having high protease productivity was obtained by the use of the clear zone method as a simple criterion for a primary screening test. Neutral and alkaline protease activities of hte mutant strain were higher than 1.8 times, comopared with those of the parental strain, respectively, while in the case of acid protease, it was 2.7 times. The mutant strain selected was more powerful in the production of cellulase and amylase, as well s protease in wheat bran, compared with those of the parental strain. protease production of the parental strain has reached maximum level at 3 days culture, while alkaline nad neutral protease production of the mutantstrain has reached at 2 days culture. On the other hand, the mutant strain formed the spore slowly, compared with the parental strain. Column chromatography of the neutral protease on DEAE-Sephadex A-50 showed that the mutant strain was not induced the formation of another neutral protease isozyme, but induced the variation in the function of regulatory gene.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.88-92
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• 1957

With the intention to examine the Korean bean "Meju" and wine "Kokja" fundamentally we accomplished first the examination of Aspergillus Oryzae in them as follow; 1. 22 kinds of Aspergillus Oryzae were isolated from Korean bean "Meju" and wine "Kokja" 2. Microscopic and physiologic characteristics were surveyed. 3. 5 kinds of powerful moulds in amylolysation and 4 kinds of powerful moulds in proteolysation were found. 4. The moulds isolated from the bean "Meju" were superior to "Kokja's" coulds in amylolytic power and proteolytic power.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.438-442
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• 1988

The enzyme produced by Rhizopus japonicus was able to convert selectively ginsenoside-Rb$_1$which is the most abundant ginseng saponin, into ginsenoside-Rd which was known to be superior to ginsenoside-Rb$_1$pharmaceutically. The convertible enzyme was purified homogeneous from wheat bran culture of Rhizopus japonicus by ammonium sulfate fractionation and column chromatography of TEAE-cellulose, DEAE-Sephadex A-50, Sephadex G-150, Sepharose 2B. Specific activity of the purified enzyme was increased to a bent 96 folds and yield was appeared to be 11% of culture extract. Evidence for homogenity was obtained from polyacrylamide and SDS-polyacrylamide gel electrophoresis. Molecular weight of the enzyme was estimated about 88, 000 daltons by Sephadex G-l50 gel filtration and SDS-polyacrylamide gel electrophoresis, and it did not consist of any subunit.

• Mycobiology
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• v.29 no.4
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• pp.210-217
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• 2001

Seventy-three species and five varieties belonging to 36 genera were collected from leaf surfaces of banana plants on glucose and cellulose-Czapek's agar at $28^{\circ}C$. The results obtained from leaf surfaces(phyllosphere and phylloplane) were basically similar on the two types of media and the most common fungi were Alternaria, Aspergillus, Chaetomium, Cladosporium, Cochliobolus, Curvularia, Gibberella, Memnoniella, Mycosphaerella, Setosphaeria and Stachybotrys. The monthly counts of these fungi were irregularly fluctuated giving maxima at various months. Chaetomium globosum was in the top of fungi in producing both exo- and endo-$\beta$-l,4-glucanases among the 34 tested isolates obtained from leaves(phylloplane) on cellulose-Czapek's agar. Maximum production of these enzymes by C. globosum was 6 and 8 days after incubation at $25^{\circ}C$ with culture medium containing wheat bran as a carbon source and peptone as a nitrogen source and initially adjusted to pH 6.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.679-684
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• 1994

For a biological control of root-knot nematode (Meloidogyne incognita) in tomato, efficiency of Bacillus thuringiensis subsp. indiana strain TH109 (BtTH109) on the nematode control was investigated. After the mixture of strain BtTH109 and wheat bran was treated into rhizosphere of the tomato plants with nematode eggs, the stem height and root growth of plants increased. And the juveniles and eggs of nematode are not found in both roots of tomatoes and pot soil after cultured broth of the strain BtTH109 treated 4 times at 3 day-interval into rhizosphere of the infected tomatoes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.6 no.1
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• pp.27-33
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• 1977

The alkaline protease was isolated from the culture of Penicillium species (P-46) grown in the wheat bran media. The crude purification of this enzyme was carried out by extraction with distilled water and precipitated with 0.7-saturated ammonium sulfate, then dialysis for 3days. The activity of this enzyme was determined by Folin's colorimetric method. The results were as follows; 1. The optimum pH and temperature of this enzyme were pH 8.4 and $45^{\circ}C$. 2. This enzyme was stable at pH $7.0{\sim}9.0$. 3. This enzyme was not inactivated by treatment in lower temperature than $30^{\circ}C$. 4. The activity of this enzyme was strongly inhibited by $Hg^{++}$ and $Cu^{++}$, but slightly by $Ag^+$ 5. This enzyme was not inhibited by cystein, thiourea, ${\varepsilon}-aminocaproic$ acid, 2, 4-DNP, EDTA but strongly inhibited by PCMB.

• The Korean Journal of Mycology
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• v.1 no.1
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• pp.23-28
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• 1973

The soil of Kwangneung area(Kyeunggi-Do) was inoculated directly into wheat-bran-media and after $3{\sim}4$ days of incubation, a Penicillium species whose cellulase activity was 1011u/g was isolated. With the treatment of mutagenic agents an improved strain(cellulase activity: 1303u/g) was obtained. This strain was screened again by mono-spore isolation method. Finally a strain C8-14 (cellulase activity: 2351u/g) which had lesser spores than the wild strain was obtained.

• Korean Journal of Microbiology
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• v.19 no.1
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• pp.31-37
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• 1981

Avicelase, CMCase and salicinase of A.phoenicis K.U. 175 were purified from wheat bran culture by salting out with ammonium sulfate, dialysis and successive column chromatography Sephadex G-100. Optimum pH and temperature of avicelase were pH 3.8-4.8, $35-55^{\circ}C$ and that of CMCase, salicinase were pH4.5-5.5, $45-60^{\circ}C$ and pH 4.5-6.0, $45-60^{\circ}C$ respectively. These enzymes were relatively thermostable, alkali unstable and inhibited by $Ca^{++},\;Mn^{++},\;Cu^{++},\;and\;Hg^{++}$. Km values of avicelase, CMCase and salicinase were calculated to be $1.5{\times}10^{-4}M,\;5.5{\times}10^{-4}M\;and\;2.75{\times}10^{-5}M$ and Vmax values $1.66{\times}10^{-4}mM/min,\;3.33{\times}10^{-4}mM/min\;and\;1.14{\times}10^{-4}mM/min$, respectively.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.457-462
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• 1988

A potent actinomycetes strain was selected to digest raw starch, which was classified as a strain of Streptomyces sp.. Its amylase production was maximized when it was grown on wheat bran extract media added 4% of cooked corn starch and 0.16% of potassium nitrate for 6 days at 3$0^{\circ}C$ and initial pH 6.2.

• Korean Journal of Microbiology
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• v.10 no.2
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• pp.69-72
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• 1972

The studies of neutral protease which was obtained by passing through Sephadex A-50 had been reported not long ago. Since that time the author also conducted the research to be investigated the physical properties of acid protease absorbed by Sephadex A-50. The results are summarized as follows : 1) Cultivating Aspergillus oryza SHW-131 on a wheat bran medium, the acid protease including neutral protease is very sensitive for temperature. 3) Activity of acid protease is very sensitive for temeprature. 3) This enzyme was proved, what is called, to be a sort of weak acid protease. It's optimum pH was lied in about 4.5. 4) A range of pH for stability is far more narrow than any other protease. 5) The acid protease is dropped by EDTA solution in its activity.