• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.355-358
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• 1986

The effects of cobalt chloride, methionine, and various carbon sources on the sisomicin production by M. inyoensis NRRL 3292 were investigated. It was found that both cobalt chloride and methionine exerted a greater stimulatory effect on sisomicin formation. Kinetic studies with various carbon sources revealed thai polysaccharide such as starch or dextrin was found io be better than glucose for sisomicin production Moreover, the relatively low concentration of dissolved carbon dioxide was one of the most important factors In accelerating sisomicin production during idiophase.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.213-218
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• 1992

Fermentation patterns were changed by adding magnesium sulfate to the fermentation broth and its effect on enhancement of sisomicin production was investigated. When cell growth was expressed by DNA content, trophophase and idiophase were separated, but not by dry cell weight. On the other hand, addition of magnesium sulfate had the antibiotic accumulated inside the cells be liberated into the outside, and this effect resulted in improving the final antibiotic yield. The maximum antibrotic yield was obtained when 100 mM magnesium sulfate was added after one day of cultivation, and enhanced more than three times compared to that of the control to which it was not added.

• Journal of Life Science
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• v.9 no.1
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• pp.8-14
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• 1999

The growth rate of the A252 strain was increased in tryptic soy broth (TSB) and malt extract-yeast extract medium (ISP-2), but the antifungal activity of culture filtrate was efficient in the media of TSB and nutrient broth. The mycelial growth and the antifungal activity of culture filtrate in TSB medium were optimized at $25^{\circ}C$ and pH 6.5. The growth in 2$\%$TSB concentration was more effective than 1$\%$, but there was no difference of the antifungal activity by the TSB concentrations. The mycelial growth of A252 strain reached to maximum at 72 hr after inoculation, whereas the antifungal activity of culture filtrate was shown to have the highest level at idiophase (60 hr) after inoculation and was decreased a little after 96 hr incubation. The antifungal activity was stable in the pH range of 4 to 11 and evenly at $121^{\circ}C$. The A252 strain was characterized as Streptomyces species by the physiological properties and examination of sporophore me morphology.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.528.3-529
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• 1986

항생물질 발효 중 자주 오염을 일으키는 원인균을 분리하여 그 특성과 오염 방지를 위한 연구를 수행하였다. 오염원인균을 분리한 결과, 열저항성 포자를 형성하며, Gram 양성, Catalase 양성, 간균인 Bacillus sp. 이었다. 이 오염균은 여러종류의 항생물질에 대하여 내성을 가지고 있었으며, R-Plasmid는 갖고 있지 않았다. 항생물질 발효시 매 24시간마다 인위적으로 오염을 시켜본 결과 초기 2일내에 오염이 되었을 경우에는 항생물질 생산이 거의 이루어지지 않았으나, 발효 3일 이후 즉 항생물질 생성시기 (idiophase)에는 오염이 되었다 하더라도 항생물질 생성에 크게 영향을 못 미쳤다. 또한 초기 오염억제의 방법으로 낮은 농도의 젠타마이신을 발효 초기에 첨가한 결과 항생물질 발효에는 영향을 주지 않고서도 오염을 억제할 수 있었다.

• The Microorganisms and Industry
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• v.18 no.3
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• pp.63-68
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• 1992

방선균에서 항생물질을 발효 생산하기 위해서는 이와 관련된 방선균의 생리학적 및 생화학적 특성을 고찰해 볼 필요가 있다. 우선, 항생물질은 방선균의 2차 대사산물로써 이의 생산은 미생물의 성장과는 거의 연계되어 있지 않다. 즉, 방선균의 발효 과정을 살펴보면, 일반적으로 균체가 성장하는 증식 단계(trophophase)와 항생물질이 생산되는 발효 단계(idiophase)로 구분할 수 있다(2). 다시 말해서, 항생물질과 같은 2차 대사산물은 균체의 성장이 어느 정도 완료되어진 이후에 생합성되어지기 시작하며, 이는 방선균의 생활 주기상의 분화과정과도 밀접한 관계를 갖고 있는 것으로 알려져 있다. 또 하나의 특징은 한 종류의 방선균으로부터 유사한 화학적 골격을 지닌 여러 종의 항생물질들이 동시에 생산되어지는 경우가 많으며, 외부 환경에 따라 그 생산량이 크게 영향을 받는다는 사실이다. 따라서 방선균에서 목적하는 항생물질만을 과량생산하기 위해서는 배지의 조성을 비롯하여 pH, 발효온도, 통기, 점도 등 여러가지 발효 조건들을 잘 조절해 주어야 한다. 이러한 관점에서 방선균을 이용한 항생물질 발효에 있어서 그 생산량을 증대시키기 위해 고려해 주어야 할 사항들을 고찰해 보기로 한다.

• Microbiology and Biotechnology Letters
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• v.14 no.4
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• pp.293-298
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• 1986

Sisomicin, which is one of aminoglycoside antibiotics, was produced by Micromonospora inyoensis. The effects of carbon sources on sisomicin production were studied in batch cultures. Starch, dextrin and maltose were good carbon sources for the production of sisomicin. However, when glucose was used, the antibiotic productivity decreased significantly due to a carbon catabolite regulation. The carbon catabolite regulation depends mostly on carbon catabolite repression, but not on carbon catabolite inhibition. On the other hand, the growth-production curves of batch cultures show that sisomicin is produced most actively during the idiophase.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.17-21
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• 2004

This study was investigated the physiological properties of auxin-producing bacteria that have plant growth promoting activity and plant pathogen antagonistic ability. Auxin-producing bacteria were isolated from field soils of Gyeongsan, Korea. Selected strains were identified as a Pseudumonas fulva N21 and a Pantoea agglomerans; K35 by morphological and physiological test, and Biolog (Microlog) system. Auxins were determined by Salkowski in vitro test and mungbean adventitious root induction bioassay. Also produced indole-3-acetic acid (IAA) was identified by TLC. During cell growth, auxin production were highest in their idiophase after log phase and $35^{\circ}C$ at pH 7.5.