• KSBB Journal
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• v.25 no.1
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• pp.79-84
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• 2010

In the present study, we isolated a new bacterial strain producing invertase (EC 3.2.1.26) and determined optimized culture condition in flask culture. The strain was identified as Bacilus flexus determined by the 16S rDNA sequencing method. The invertase was produced only in the sucrose medium as the sole carbon source. Potassium nitrate was an adequate nitrogen source for enzyme production, whereas meat peptone showed the highest bacterial growth. Enzyme production was increased about 2-fold when $MgSO_4\cdot7H_2O$ was supplemented to the growth media. The optimum temperature was found to be $30^{\circ}C$ for both enzyme production and bacterial growth. Invertase exhibited pH optima in the range 5.0-6.0 and have a temperature optimum at $40^{\circ}C$, similarly to other invertases found from different microbial sources. Several mineral ions (K and Fe) stimulated the invertase activity, whereas some bioelements (Ag, Mg, and Mn) inhibited enzyme activity. Under the optimized culture condition, the maximum enzyme production (over 250 units/mL) was achieved at 20 h. To the best of our knowledge, this is the first time to report on invertase production by Bacilus flexus.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.798-804
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• 2007

A Actinomycetes F-97 producing tyrosinase inhibitor was isolated from soil samples. The optimum culture condition for 쇼rosinase inhibitor production was investigated and the results were as follows. The best carbon source for tyrosinase inhibitor production was shown as soluble starch, the optimum concentration was 3.0%. The best nitrogen source for tyrosinase inhibitor production was shown as peptone, the optimum concentration was 0.36%. As effect of metal ions on the production of tyrosinase inhibitor, K$_2$HPO$_4$ was shown the best and the optimum concentration was 0.1 mM. The optimum pH and temperature was shown 7.0 and 30${\circ}$C, respectively. And the highest tyrosinase inhibitor production was observed at 70hr cultivation under optimum conditions in jar fermentor scale.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.210-215
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• 2006

Diplodia gossypina ATCC10936 produced chiral specific (+)-jasmonic acid (JA) that is the most biologically active form. (+)-JA is a plant growth hormone and also one of the most important aroma compounds responsible for jasmin-like aroma note. In order to develop a commercial bioprocess for the production of (+)-JA, optimal culture conditions for D. gossypina ATCC10936 were investigated. D. gossypina produced (+)-JA using either fructose and glucose as a sole carbon source. As a nitrogen source, $NaNO_3$ gave relatively high (+)-JA production. The optimal temperature for the production of (+)-JA by D. gossypina was $28^{\circ}C$, and optimal agitation was found to be 200 rpm. D. gossypina produced (+)-JA upto 600 mg/L in SM medium, although the highest level of biomass was obtained in PDMYS medium.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.68-72
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• 2005

The production of antibiotic substances by Serratia plymuthica A21-4 was greatly enhanced by modifying components of a growth medium. When the minimal medium containing $K_2HPO_4$ 0.7%, $KH_2PO_4$ 0.2%, $(NH_4)_2SO_4$ 0.1%, $MgSO_4$ 0.01% was used as basal medium, the best carbon source for antibiotic production was glycerol and the most favorable nitrogen source was ammonium sulfate. The modified medium for antibiotic production also increased colonization ability of A21-4 on pepper root and in the rhizosphere soil. When the cells of A21-4 were suspended in modified medium, the population density of A21-4 on pepper root was 10-100 times higher than that suspended in 0.1 M $MgSO_4$. The population density of A21-4 on root did not decrease under $10^6$ cfu/groot up to 21 days after treatment although the inoculum of A21-4 was reduced to $10^7$ cell/ml. Similar tendency was also observed in the rhizosphere soil. Consequently, Phytophthora blight of pepper was successfully controlled by A21-4 with $10^7$ cell/ml suspended in the modified buffer solution instead of $10^9$ cfu/ml suspended in 0.1 M $MgSO_4$.

• Microbiology and Biotechnology Letters
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• v.8 no.2
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• pp.119-123
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• 1980

Culture conditions of yellow pigment in Monascus sp. were studied. According to the studies of culture conditions optimum condition was found to be pH 4.5, 3 days of incubation with 3% of sucrose as carbon source, 0.2 ％ of yeast extract as nitrogen source and 75m1 of medium in the 500m1 erlenmyer flask by rotary shaking (rpm 180) at 180 r.p.m. Effective levels of inorganic compounds were found to be 0.25 % of potassium phosphate monobasic and 0.1 ％ of Magnesium sulfate.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.194-199
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• 1998

Pholiota sp. were collected from the forest of Kangwon province (Mt. Samak, Mt. Odae and Kangwon National University Forest Experimentation) from the early of August to the end of October 1997. Among these fungi, Poliota adiposa was selected for culture experiment because it is suitable for edible mushroom. The Optimal temperature for the mycelial growth of Pholiota adiposa was in the range of $28^{\circ}C$ while that of fruit body formation was $15{\pm}1^{\circ}C$. Brown sugar as carbon source and soybean flour as nitrogen source were good for mycelial growth in commercial liquid culture. The fruit bodies of Pholiota adiposa were artifitially produced on plastic bottle including poplar sawdust and rice bran (4:1).

• Applied Biological Chemistry
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• v.41 no.7
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• pp.496-499
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• 1998

For the production of theobromine from caffeine, 5 strains of bacteria capable of producing theobromine were isolated from soil. Among them, the strain CT-017 showed the best ability of producing theobromine, and was partially identified as a Pseudomonas sp. For the production of theobromine, fructose was the most effective carbon source at an optimum concentration of 5 g/l. The most effective nitrogen source was 5 g/l of beef extracts. And 0.02 g/l of $Fe^{2+}$, 1.0 g/l of threonine were effective for the production of theobromine. The optimum temperature and initial pH were $28^{\circ}C$ and 6.5, respectively. After 23 hr cultivation, 7.98 g/l of theobromine was produced from 15 g/l of caffeine which corresponds to a conversion yield of 53.2%.

• Applied Biological Chemistry
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• v.27
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• pp.47-55
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• 1984

The results of series studies on the ratio of supplements, out-door composting and out-door fermentation induced by using the rice straw as a main substrates at the cultivation of Agaricus bisporus, and the cultivation of Pleurotus ostreatus using the rice straw bundles on its compost are as follows; When rice straw for cultivation of A. bisporus was used as the main substrates in synthetic compost as a carbon source, yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw and the total nitrogen content was high in rice straw compost. Use of barley straw compost for cultivation of A. bisporus was shown of low yield compared with rice straw, but when a 50% barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. The total organic nitrogen on the compost were shown the positive relation to the yield of A. bisporus, but the ammonium nitrogen negative relation to the mycelial growth and yield of A. bisporus. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. The supplementation of organic nutrient activated compost fermentation and increased yield of A. bisporus. The best sources of organic nutrients selected were as follows: perilla meal, sesame meal, wheat bran and poultry manure, etc. Soybean meal, tobacco powder and glutamic acid fermentation byproducts which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. During out door composing of rice straw for cultivation of A. bisporus, using of tuner, composter and tunnel system increased up to 13% of its yield, and also cut down 34% of production Cost. The cultivation of P. ostreatus and utilizing of rice straw and wheat straw was established and its yield was high on the rice straw pots. When the substrates 'Rice straw' was heated by steam at $60^{\circ}C$ for 6 hr. mycelial growth of P. ostreatus was moderately rapid and its yield was high.

• Journal of the Korean Wood Science and Technology
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• v.24 no.4
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• pp.74-81
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• 1996

리그닌분해능(分解能)이 높은 균주(菌株)로 선발(選拔)된 Coriolus versicolor-13 (CV-13), LKY-7 및 LKY-12세 균주(菌株)에 대하여 균체외(菌體外) laccase 생산(生産)을 검토(檢討)하였다. Glucose-peptone broth에서 균체외(菌體外) laccase활성(活性)은 CV-13의 경우 3일 이상배양후(以上培養後)에 나타났고 LKY-7과 LKY-12균주(菌株)의 laccase 활성(活性)은 배양(培養) 2일째에 검출(檢出)되었다. 탄소원(炭素源)으로서는 maltose가 glucose와 비슷한 laccase 생산효과(生産效果)를 나타냈고 질소원(窒素源)으로서는 유기태질소(有機態窒素)가 무기태(無機態) 질소(窒素)보다 효과적(效果的)이었다. Laccase 유도물질(誘導物質)로서는 2,5-Xylidine이 가장 우수하였으며 1mM 이하(以下)의 농도(濃度)에서는 유도효과(誘導效果)가 크게 나타났으나 1.5mM 이상(以上)의 농도(濃度)에서는 laccase생산(生産)이 억제(抑制)되었고, 균사생장(菌絲生長) 초기(初期)에 첨가(添加)하는 것이 효과적(效果的)으로 나타났다. SDS-PAGE 후, CV-13 균주(菌株)의 균체외(菌體外) 단백질(蛋白質)에서는 약 69, 66, 25, 23, 19kDa 크기의 laccase band가 5개 나타났고 LKY-7 균주(菌株)에서는 27kDa과 19kDa 크기의 2개 band가, LKY-12 균주(菌株)에서는 22, 20, 17kDa 크기의 laccase band가 3개 나타났다.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.332-337
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• 1994

Under standard condition (Han, et al., 1990: glucose 1%-nitrate 0.1% minimal medium, 30 ml in 9 cm plate, $10^6$ cells of inoculum per plate), wild type of Aspergillus nidulans developed both sexual and asexual organs in ballance, while velA1 mutant developed asexual ones preferentially. Increase of glucose concentration did not significantly affect the asexual sporulation. However, development of sexual organs were largely affected. It was greatly enhanced when favorable nitrogen source, for example, casein hydrolysate was added, which is contrary to the case of Neurospora or Saccharomyces where limitation of N source induces sexual development. On most of moderate C sources asexual development in $velA^+$ strain was largely inhibited except acetate on which only asexual spores were produced, while that in velA1 mutant strain was not affected. Lactose promoted the sexual development even in velA1 mutant indicating that lactose itself or its metabolic intermediate may induce sexual development independent of allelic state of velA gene. On other moderate favorable C sources, glycerol, galactose and ethanol, asexual development was largely inhibited in $velA^+$ strain but not in velA1 mutant strain. Sexual organs were, however, never produced on acetate. These results suggested that asexual development of wild type is largely dependent on C sources and the velA gene is involved in the repression of asexual development in not-enough-grown (non-competent) thalli resulting in preferential progression of sexual development.