• Mycobiology
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• 제43권1호
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• pp.87-91
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• 2015

Eighteen endophytic fungi with different colony morphologies were isolated from the roots of Nymphoides peltata growing in the Dalsung wetland. The fungal culture filtrates of the endophytic fungi were treated to Waito-c rice seedling to evaluate their plant growth-promoting activities. Culture filtrate of Y2H0002 fungal strain promoted the growth of the Waito-c rice seedlings. This strain was identified on the basis of sequences of the partial internal transcribed spacer region and the partial beta-tubulin gene. Upon chromatographic analysis of the culture filtrate of Y2H0002 strain, the gibberellins (GAs: $GA_1$, $GA_3$, and $GA_4$) were detected and quantified. Molecular and morphological studies identified the Y2H0002 strain as belonging to Aspergillus clavatus. These results indicated that A. clavatus improves the growth of plants and produces various GAs, and may participate in the growth of plants under diverse environmental conditions.

• 미생물학회지
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• 제37권1호
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• pp.21-27
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• 2001

Bacillus anthracis Sterne 34F$_2$균주로부터 PA를 생산하기 위해 RM배지를 변형하였다. NaHCO$_3$를 8 g/l에서 10 g/l로, glucose를 5 g/l로 첨가하여 새로운 배지조성에서 탄저균을 배양한 후, 배양액을 hydroxyapatite를 이용하여 농축하였다. 농축된 조단백질을 hydroxyapatite column chromatography, DEAE-Sepharose CL-4B column chromatography 및 Toyo-pearl gel filtration chromatography를 사용하여 PA를 정제하였다. 변형된 RM 배지를 사용해 얻은 PA 양은 8.6 mg/l 이었다.

• 생명과학회지
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• 제20권9호
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• pp.1373-1377
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• 2010

해안사구식물은 다양한 미생물과 외생균근과 내생균근의 도움으로 효과적으로 생존할 수 있다. Penicillium citrinum KACC43900를 이용하여, 해안사구식물인 갯메꽃과 갯쇠보리에 대해 생장 촉진효과를 조사하였으며, 지상부길이, 식물체길이 그리고 식물체건량을 분석하였다. P. citrinum KACC43900 배양액을 20일간 처리 시, 지상부길이는 16.30 cm와 10.56 cm이었으며, 대조구는 8.60 cm과 8.12 cm인 것을 확인 하였다. 마찬가지로 P. citrinum KACC43900 배양액을 20일간 처리 시, 갯메꽃과 갯쇠보리의 식물체길이는 24.06 cm와 17.06 cm인 것을 확인 하였고, 대조구는 14.90 cm과 14.80 cm인 것을 확인 하였다. 갯메꽃의 식물체건량은 배양여과액 처리의 경우, 0.163g이었고 대조구가 0.123 g이었다. 그리고 갯쇠보리의 식물체건량은 배양여과액 처리의 경우, 0.032 g이었으며 대조구가 0.027 g이었다. 갯메꽃과 갯쇠보리의 지상부길이는 P. citrinum KACC43900의 배양여과액에 의해 89.54%와 29.60% 촉진되었다.

• Mycobiology
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• 제45권3호
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• pp.192-198
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• 2017

The green peach aphid (Myzus persicae), a plant pest, and gray mold disease, caused by Botrytis cinerea, affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae. Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection.

• Applied Biological Chemistry
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• 제36권5호
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• pp.352-357
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• 1993

S.G.Y.배지(skim milk, glucose, yeast extract)와 S.M.W.배지(skim milk whey). 배지에 P. freudenreichii KFCC 31227과 L. acidophilus KFCC 32825를 단독 또는 혼합배양 후, 두 균주의 생육 및 유기산 생성에 미치는 발효여액의 영향과 당의 변화 및 이용 효과를 검토한 결과, 자신의 발효여액보다는 상대편의 발효여액에서 그리고 단독배양보다는 혼합배양에서 생육이나 산 생성의 효과가 촉진되었으며, 배지중의 glucose 및 lactose 의 이용효과를 보면 P. freudenreich-ii KFCC 31227 단독 배양시는 lactose 를, L. acdophilus KFCC 32825 단독배양시는 glucose를 생육이나 산 생성에 더 잘 이용하였다. 또한 두 균주의 혼합배양시에는 단독배양에 비해 발효에 glucose 나 lactose 를 이용하는 시간이 더욱 단축되는 결과로 나타났으며, 이것은 혼합배양시 두 균주의 상호작용에 의한 synergism 효과에 기인된 것으로 생각된다.

• 한국유기농업학회지
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• 제6권2호
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• pp.117-125
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• 1998

For isolation of antagonistic fungi antagonistic to Phytophthora capsici, a total of 157 isolates of fungi were screened from soil. Among the 157 isolates further screened by the dual culture test on potato dextrose agar and V-8 juice agar, 16 isolates were tested to show their antagonistic activity against P. capsici and Fusarium oxysporum. Fungal cul-ture filtrates of screened 16 isolates were shown to inhibit germination of zoospoorangia of P. capsici entirely and conidia of F. oxysporum considerably. Antagonistic fungi were shown to suppress of P. capsici infection of red-pepper plants maintained in the green house. Four isolates. 27 J5, 37 J10, 36 J13 and 31 K10, with the reduced disease incidence 53.3∼60.0% were identified as Fusarium sp. (27 J5). Trichoderma sp. (37 J10, 36 J13) and Penicillium sp. (31 K10).

• 한국해양바이오학회지
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• 제9권2호
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• pp.49-57
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• 2017

We isolated marine bacterium, isolate DG-2 which produces the antibiotics against MRSA (methicillin-resistant Staphylococcus aureus). This isolate DG-2 was examined by its morphological, biochemical properties, and 16S rRNA sequencing analysis. And then, isolate DG-2 was identified to the genus Streptomyces. Therefore, this isolate was designated as Streptomyces sp. DG-2. Streptomyces sp. DG-2 grew relatively well at $25^{\circ}C$, pH 7.0, and NaCl 1.0%. For the pre-purification of the bioactive compounds, DG-2 was fermented in 30 L PPES-II medium, and the culture filtrates of DG-2 was extracted by ethyl acetate. The ethyl acetate extract of DG-2 showed the significant anti-MRSA and antibacterial activities.

• Food Science and Biotechnology
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• 제18권6호
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• pp.1365-1370
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• 2009

Aspergillus kawachii extracellular pectinases were screened in liquid cultures with different carbon sources. The fungus grown on citrus pectin or lemon pomace produced at least one of these inducible pectinases: acidic polygalacturonase, pectin lyase, pectin methylesterase, $\alpha$-L-arabinofuranosidase, $\alpha$-1,5-endoarabinase, $\beta$-D-galactosidase/exogalactanase, and $\beta$-1,4-endogalactanase. The lemon-pomace filtrates also contained significant $\alpha$-L-rhamnosidase and $\beta$-D-fucosidase activities. Most of the screened pectinases were active at pH 2.0-2.5, indicating that the A. kawachii enzymes were acidophilic. Under the culture conditions employed we could not detect enzymatic degradation of soybean rhamnogalacturonan. The A. kawachii pectinase-production-related regulatory phenomena of induction-repression resemble those described for other Aspergillus sp.

• 미생물학회지
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• 제24권1호
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• pp.51-56
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• 1986

Eight strains of the bacteria capable of growing on salicylate as the sole carbon source were isolated form soil and river water. Three of these isolates were identified as Acinetobacter calcoaceticus (AcBl), Pseuomonas putida biotype B (PpB2), and P. putida biotype A (PpB3). Effects of temperature, pH and C source concentration on biodegradation of salicylate by PpB3 were wxamined. The optimum conditions were as follows; $30^{\circ}C$ for temperature, 7.0 for pH, and 10mM for C source concentration. Ultraviolet scanning spectrum of the salicylate was measured. The spectrum has two peaks at 225nm and 292nm. The spectra of the culture filtrates indicate that ring degradation of salicylate is accomplished.

• 대한미생물학회지
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• 제8권1호
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• pp.43-52
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• 1973

Twenty culture filtrates among the various isolated strains from foodstuffs were submitted for toxicity screening using HeLa cells and mice. Fourteen strains(70%) were toxic to both HeLa cells and mice, 17 strains(85%) to HeLa cell alone and 14 strains(70%) to mice alone. As a mass screening this method employed is feasible to detect mycotoxin-producing fungi. In most instances, the results obtained by HeLa cells were in good parellelism with those obtained by mice.