• Journal of Microbiology and Biotechnology
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• v.22 no.5
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• pp.674-683
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• 2012

A new strain, SD12, was isolated from tannery waste polluted soil and identified as Pseudomonas aeruginosa on the basis of phenotypic traits and by comparison of 16S rRNA sequences. This bacterium exhibited broad-spectrum antagonistic activity against phytopathogenic fungi. The strain produced phosphatases, cellulases, proteases, pectinases, and HCN and also retained its ability to produce hydroxamate-type siderophore. A bioactive metabolite was isolated from P. aeruginosa SD12 and was characterized as 1-hydroxyphenazine ((1-OH-PHZ) by nuclear magnetic resonance (NMR) spectral analysis. The strain was used as a biocontrol agent against root rot and wilt disease of pyrethrum caused by Rhizoctonia solani. The stain is also reported to increase the growth and biomass of Plantago ovata. The purified compound, 1-hydroxyphenazine, also showed broad-spectrum antagonistic activity towards a range of phytopathogenic fungi, which is the first report of its kind.

• Journal of Life Science
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• v.9 no.3
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• pp.314-327
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• 1999

This study was investigated to isolate identify the total bacteria and fungi from the indoor air of work-place of the shoes, paint, stainless steel, and plastic industries. The number of bacterial colonies on the nutrient agar plates were calculated by the open petridish method for 30 minutes in indoor air of work-places at the autumn and winter. The isolated bacteria were identified by Gram stain and biochemical test using API Staph and API 20E kits. The isolated fungal colonies were identified by gross appearance of the giant colonies and microscopic examination of their spore and hyphal characteristics on the slide culture method. The minimum inhibitory concentration (MIC) of several antibiotics against isolated bacteria was determined by the microdilution method with Mueller-Hinton broth. The 70-400 colonies in autumn and 54-236 colonies in winter were isolated from the indoor air of work-places of several industry. The isolation rates of Gram positive cocci, Gram positive bacilli, Gram negative bacilli, and Gram negative cocci were 46.3%, 19.8%, 17.3%, and 16.1%, respectively. In Gram positive cocci, the most strains were identified as Aerococcus spp, Micrococcus spp, and Staphylococcus spp. In Gram positive and negative bacilli, and Gram negative cocci were identified as Bacillus spp, Pseudomonas spp, and Neisseria spp, respectively. The frequently isolated fungi were Aspergillus spp, Penicillium spp and Rhizopus spp, respectively. The frequently isolated Aerococcus spp, Micrococcus spp, and Staphylococus spp were highly resistance against ampicillin, erythromycin, methicillin, and tetracycline. These results arouse our attention to microbiologic pollution in the indoor air of work-places of industries.

• Korean Journal of Veterinary Pathology
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• v.7 no.1
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• pp.67-69
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• 2003

Three mature layer chickens from a farm in which chickens showed green diarrhea, cyanosis, lethargy, loss of appetite were pathologically examined. Grossly, multiple variable sized caseous nodules were detected in the liver, intestinal serosa and mesentery. In addition, parathypoid nodules in the liver and fibrous serositis on the several peritoneal organs and tissues were noticed. One of spleens had multiple infarction areas. Histologically caseous nodules consisted of central caseous core and peripheral epithelioid cells overlying the fibrous connective tissue. Multinucleated giant cells were scattered between the epithelioid cells and fibrous connective tissue. In these nodules Gram negative cocobacilus bacterial colonies were present, whereas Periodic Schiff reaction and Ziehl-Neelsen stain detected neither fungi nor acid fast bacteria. From these results multiple granulomas might be induced by Escherichia coli. In addition, severe Ascafdiodf and Salmonellosis were coinfected in these chickens.

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.41-46
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• 1993

A strain showing antibiotic activities against various bacteria and fungi was selected from approximately 2,000 microorganisms obtained from soil samples. This strain, designated as KH-431, was identified as a Clostridium sp. by its morphological, physiological and biochemical characteristics. The highest production of the antibiotics was achieved in a fermentation medium containing sorbitol, yeast extract, d-biotin and $CaCl_2$ The antibiotics were isolated from the culture broth by solvent extraction using ethyl acetate, silica gel column chromatography and recrystallization. Two kinds of antibiotics, KG-431A and KG-431B were obtained after the purification procedure, and only KG-431B was successful to recrystallize.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.73-81
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• 2004

To develope of the inexpensive anti-stain chemicals, it was conducted to investigate the inhibitory effectiveness of mycelial growth and anti-mold effectiveness against test fungi causing surface mold of wood, iron corrosivity and hygroscopicity of six fluoride-based chemicals made from industrial by- product.Among the six chemicals. RNF-3 and RNF-4 were the most effective with respect to a mycelial growth control and anti-mold effectiveness. For the wood treatment with these chemicals, the optimum concentration was about 2% and there was no difference in the effectiveness of chemicals between wood species. The wood treated with synthesized chemicals showed a relatively high iron corrosion rate for corrosive F component whereas, in the treatment with RNF-3 and RNF-4, there was no difference from the untreated wood when the concentration was less than 2%. The hygroscopic property of wood was not effected by treatment of these chemicals. To prove the feasibility for practical using of RNF-3 and RNF-4 chemicals, it is necessary to test of anti-mold effectiveness in the sawmill by field test.

• Journal of Environmental Science International
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• v.14 no.9
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• pp.811-815
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• 2005

The activated sludge from the aeration basin of the Su-yeong municipal wastewater treatment plant which has operated by a standard activated sludge process in Busan, Korea was investigated during April 2004 and January 2005 with several bio-indicators. The number of bacteria and fungi per gram of dry weight of MLSS were estimated to be $3.1\times10^6\sim1.5\times10^8\;and\;l.1\times10^3\sim1.1\times10^5$ colony forming units, respectively, by the plate agar method. By cultivation-independent methods, such as 4',6-diamidino-2-phenylindole stain and fluorescence in situ hybridization, the ratio of eubacteria to the entire biomass was evaluated by more than $80\%$ (v/v). The ratio of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria to the total eubacteria was detennined to be $7.0\sim9.8\%\;and\;3.3\sim6.2\%$ without heavy variation in spite of a period of relatively low temperature in the basin. It would be expected that the nitrification would occur or at least co-exist throughout the year in the sludge of many municipal WWTP with influents that contain the sufficient nitrogen sources although the WWTP does not have any specialized processes for the removal of nitrogen.

• Mycobiology
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• v.38 no.4
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• pp.286-294
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• 2010

Epicoccum purpurascens stain 5615 AUMC was investigated for its biocontrol activity against root rot disease caused by Pythium irregulare. E. purpurascens greenhouse pathogenicity tests using three leguminous plants indicated that the fungus was nonpathogenic under the test conditions. The germination rate of the three species of legume seeds treated with a E. purpurascens homogenate increased significantly compared with the seeds infested with P. irregulare. No root rot symptoms were observed on seeds treated with E. purpurascens, and seedlings appeared more vigorous when compared with the non-treated control. A significant increase in seedling growth parameters (seedling length and fresh and dry weights) was observed in seedlings treated with E. purpurascens compared to pathogen-treated seedlings. Pre-treating the seeds with the bioagent fungus was more efficient for protecting seeds against the root rot disease caused by P. irregulare than waiting for disease dispersal before intervention. To determine whether E. purpurascens produced known anti-fungal compounds, an acetone extract of the fungus was analyzed by gas chromatography mass spectrometry. The extract revealed a high percentage of the cinnamic acid derivative (trimethylsiloxy) cinnamic acid methyl ester. The E. purpurascens isolate grew more rapidly than the P. irregulare pathogen in a dual culture on potato dextrose agar nutrient medium, although the two fungi grew similarly when cultured separately. This result may indicate antagonism via antibiosis or competition.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.798-803
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• 2015

This study was conducted to predict the effect of door opening in wooden cultural heritages (WCHs) on their conservation environment. For this prediction, measured relative humidity (RH) and surface wood moisture content (MC) of inner part of wood columns in open wooden building and neighboring closed wooden building were compared with minimum RH, including the duration of minimum RH, and MC required for spore germination and resultant growth of wood-degrading fungi reported in some literatures. Moisture conditions, namely RH of inside wooden building and MC of wood was unsuitable for decay and sap-stain fungi all the year round; however, moisture conditions during summer season was suitable for spore germination and resultant growth of surface mold fungi, regardless of door opening. When compared, the duration of minimum (75%) or higher RH and the number of wood columns with MC level greater than the minimum MC (15%) during summer season, the surface mold related to the conservation environment of inside wooden building was somewhat better in open building than in closed building. Rather, doors should be opened in closed building for reducing indoor RH as a necessary measure during summer season when outdoor RH is high.

• Korean Journal of Microbiology
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• v.33 no.1
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• pp.31-37
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• 1997

Intergeneric hybrids between Aspergillus niger and Perricillium ch~y.sop~um(Tyr ), hyperlipolytic enzyne-producing fungi, were obtained by nuclear transfer technique:. Optimal conditions for formation of intergeneric hybrids were investigated. Maximum production of protoplasts were obtainrd by 1% Novozym 234 at $30^{\circ}C$ for 3 hrs and the most effective osmotic stabilizers for the isolation of protoplasts were 0.6 M KC]. Frequencies of hybrid formation by nuclear transfer were $1.3{\times}$10^{-3}$$ $-3.8{\times}$10^{-3}$$. From the chervation of genetic stability, conidial size, DNA content, ;md nuclear stain, it was suggested that their karyotypes are aneuploid. The hybrids showed 1.4-2.2 fold higher lipase activities than parental strains. It was strongly supported by results of this study that nuclear transfer technique is much more efficient in the formation of intergeneric hybrids than protoplast fusion and is very useful for the improvement of strains.

• Microbiology and Biotechnology Letters
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• v.50 no.2
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• pp.245-254
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• 2022

Cellulases are a group of biocatalyst enzymes that are capable of degrading cellulosic biomass present in the natural environment and produced by a large number of microorganisms, including bacteria and fungi, etc. In the current study, we isolated, screened and characterized cellulase-producing bacteria from soil. Three cellulose-degrading species were isolated based on clear zone using Congo red stain on carboxymethyl cellulose (CMC) agar plates. These bacterial isolates, named as HB2, HS5 and HS9, were subsequently characterized by morphological and biochemical tests as well as 16S rRNA gene sequencing. Based on 16S rRNA analysis, the bacterial isolates were identified as Bacillus cerus, Bacillus subtilis and Bacillus stratosphericus. Moreover, for maximum cellulase production, different growth parameters were optimized. Maximum optical density for growth was also noted at pH 7.0 for 48 h for all three isolates. Optical density was high for all three isolates using meat extract as a nitrogen source for 48 h. The pH profile of all three strains was quite similar but the maximum enzyme activity was observed at pH 7.0. Maximum cellulase production by all three bacterial isolates was noted when using lactose as a carbon rather than nitrogen and peptone. Further studies are needed for identification of new isolates in this region having maximum cellulolytic activity. Our findings indicate that this enzyme has various potential industrial applications.