• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.530-534
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• 1990

A strain of actinomycetes, Thermoactinomyces sp. CH-53, was isolated from manure and composted livestock feces. Actinornycetes-feed additive was prepared with the solid wheat bran medium of Thermoactinomyces sp. CH-53 that grew vigorously on unsterilized poultry feces at $50^{\circ}C$. pH 6.5- 9.5 and moisture content of 55-65% and added at a rate of 1% (wtlwt) to the commercially assorted feed to be fed poultry. The excreted feces contained $10^7-10^8$. Thermoactinomyces sp. CH-53 cells per gram. Poultry feces malodour was got rid of during treatment. The effect on plant growth was evaluated on the basis of the amount of nitrogen as fertilizer under a loading of 0.2g N1600g soillpot. A11 samples were showed a promotion effect for plant growth. The treated poultry feces added from O.lg to 0.4g total nitrogen per 600g soil in a pat increased the growth of Brassica rapa var. perui-ridis.

• Journal of Environmental Science International
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• v.6 no.2
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• pp.153-163
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• 1997

In order to fad the most fitted biodegradation model, biodegradation kinetics model to the initial phenol and p-cresot concentrations were investigated and had been fitted by the linear regression. Bacteria capable of degrading p-cresol were isolated from soil by enrichment culture technique. Among them, strain Ml capable of degradillg p.rcresol has also degraded phenal and was identified as the genus Micrococcus from the results from of taxonomical studies. The optimal tonditlons for the biodegradation of phenal and p-cresol by Micrococcus sp. Ml were $NH_4NO_3$ 0.05%, pH 7.0, 3$0^{\circ}C$, respectively, and medium volume 100m1/250m1 shaking flask. iwicrococcus sp. Ml was able to grow on phenal concentration up to 14mM and p-cresol concelltration up to 0.8mM. With increasing substrate concentraction, the lag period increased, but the maximum specific growth rates decreased. The yield coefficient decreased with increasing substrate concentation. The biodegradation kinetics of phenol and p-cresol were best described by Monod with growth model for every experimented concentration. In cultivation of mixed substrate, p-cresol was degraded first and phenol was second. This result implies that p-cresol and phenol was not degraded simultaneously.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.790-795
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• 1995

Flocculant-producing microorganisms were isolated from soil samples using kaoline as the flocculating test material. One strain that had high flocculating activity among them was selected and identified as Arcuadendron sp. TS-49. The favorable medium for production of the flocculant was 3% glucose, 0.2% yeast extract, 0.1% $NH_4Cl$, 0.01% $MgSO_4$, and 0.05% $MnSO_4$ in 150ml of T.W. with initial pH 7.0.The optimum culture temperature and pH were $30^{\circ}C$ and pH 7.0, respectively. The flocculant activity was observed most highly after 4 to 5 days of cultivation at the optimum condition and decreased significantly with the lapse of cultivation time. The flocculant was produced constituently and seemed to be degraded for ressimilation during cultivation. The productivity achieved by this system was about ten-fold higher than that of scrrening mediuim. This bioflocculant flocculated all tested solids, including various microorganisms and organic/inorganic compounds. Several qualitative analyses of the bioflocculant showed that it was a kind of glycoprotein containing sugars and protein.

• Journal of the Korean Geotechnical Society
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• v.33 no.1
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• pp.39-56
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• 2017

Distribution of both axial force and skin friction should be investigated in order to estimate pull-out capacity of ground anchors. Numerical method of computing load-transfer characteristics of the ground anchors, however, has not been specified and studies on this area are not sufficient. This study suggested the numerical method of simulating the characteristics of axial force and skin friction distribution against the tension type ground anchors. Also, debonding behaviors of skin friction and axial force were calculated by the suggested numerical method as a function of load levels. As a result of the review, it is confirmed that the distributions of axial force and skin friction by the suggested numerical method are relatively similar to those of field test results.

• KSBB Journal
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• v.14 no.2
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• pp.174-180
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• 1999

An actinomycetes strain No.4 which produce the cholesterol oxidase(EC 1.1.3.6), was isolated from soil and identified as Streptomyces sp. based on taxonomic studies. The conditions of cholesterol oxidase production and enzymatic properties were investigated. The optimum composition of medium for production of the enzyme was 1% soluble starch, 2% corn steep liquor, 0.1% $KH_2PO_4$, 0.1% $NaNO_3$ and 0.05% $MgSO_4$ (pH 7.0). The optimum pH and temperature of the cholesterol oxidase were pH 6.0~7.5 and $37^{\circ}C$, respectively. The enzyme was stable in the range of pH 6.0~9.0. The isoelectric point determined by multichambered electrofocusing unit was in the range of pH 6.0~6.5.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.1
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• pp.17-22
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• 2004

A bacterial strain WJ-98 found to produce active extracellular keratinase was isolated from the soil of a poultry factory. It was identified as Paracoccus sp. based on its 16S rRNA sequence analysis, morphological and physiological characteristics. The optimal culture conditions for the production of keratinase by Paracoccus sp. WJ-98 were investigated. The optimal medium composition for keratinase production was determined to be 1.0% keratin, 0.05% urea and NaCl, 0.03% K$_2$HPO$_4$, 0.04% KH$_2$PO$_4$, and 0.01% MgCl$_2$$.$6H$_2$O. Optimal initial pH and temperature for the production of keratinase were 7.5 and 37$^{\circ}C$, respectively. The maximum keratinase production of 90 U/mL was reached after 84 h of cultivation under the optimal culturing conditions. The keratinase from Paracoccus sp. WJ-98 was partially purified from a culture broth by using ammonium sulfate precipitation, ion-exchange chromatography on DEAE-cellulose, followed by gel filtration chromatography on Sephadex G-75. Optimum pH and temperature for the enzyme reaction were pH 6.8 and 50$^{\circ}C$, respectively and the enzymes were stable in the pH range from 6.0 to 8.0 and below 50$^{\circ}C$. The enzyme activity was significantly inhibited by EDTA, Zn$\^$2+/ and Hg$\^$2+/. Inquiry into the characteristics of keratinase production from these bacteria may yield useful agricultural feed processing applications.

• Korean Journal of Environmental Biology
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• v.27 no.4
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• pp.384-390
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• 2009

An antifungal antibiotic-producing bacterium was isolated from soil and identified as Bacillus sp. CJ-1. The culture supernatant was found to have a strong and stable antifungal activity against Colletotrichum gloeosporioides. Culture conditions for the maximum antifungal activity were examined. Glucose and yeast extract were selected as the best carbon and nitrogen sources. The optimum C/N ratio was 3. The optimum temperature and initial pH were determined as $35^{\circ}C$ and 6.0, respectively. Under these conditions, the production for the antibiotic was maximized at 72 hr at $35^{\circ}C$ after cultivation. Microscopic observation showed that the culture supernatant of Bacillus sp. CJ-1 had a strong inhibitory activity on the mycelial growth of the test strain at above $12.5\;{\mu}L\;mL^{-1}$ of concentration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.427-432
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• 2009

Seashore Paspalum (Paspalum vaginatum Swartz) is a warm season grass and indigenous to tropical and subtropical regions of coastal areas worldwide. The species is used as feed for cattle and horses and has been very successful for golf courses worldwide. One of the most outstanding characteristics of seashore paspalum is its tolerance to saline soils compared to other warm season turfgrasses. The development of new seashore paspalum cultivars with improved traits could be facilitated through the application of biotechnological strategies. The purpose of this study was to product for herbicide resistant seashore paspalum using Arobacterium-mediated transformation and this study is the first report on transformation and herbicideresistant transgenic plants in seashore paspalum. Embryogenic calli were induced from the seeded variety of pseashore paspalum. Embryogenic calli were transformed with Agrobacterium tumefaciens strain EHA105 carrying the binary vector pCAMBIA3301 with two genes encoding gusA and bar. Transformed calli and plants were selected on medium containing 3 mg/l PPT. PCR detected the presence of the gusA and bar gene, indicating both genes are integrated into the genome of seashore paspalum. A chlorophenol red assay was used to confirm that the bar gene was expressed. By application of herbicide BASTA, the herbicide resistance in the transgenic seashore paspalum plants was confirmed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.3
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• pp.195-204
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• 1998

This study was designed to investigate the effects of antagonistic microorganism, Bacillus subtilis, on the growth of forage seedlings in repeated cultivation soils and unrepeated cultivation soils. The field experiment was wnducted in pots in a vinyl house using repeated and unrepeated cultivation soils. Forage types were 'Suwon 19' wrn(Zea mqs L.), 'Califbmia' white clover(Tr~oIium repens L.) and 'Fawn' tall fescue (Festuca arundianacea Schreb.). Samples of white clover and tall fescue were taken h m each pot at 36 days after seeding. Samples of wm were examined at 50 days after seeding. The most active antagonistic bacterium was isolated h m forage rhizosphere soil, and selected by reference to it's antagonistic ability on the growth of pathogenic fungi, Rhizoctonia solmi and Fusarium oxyspomm, and it was identified as Bacillus subtilis. This strain strongly suppressed the growth of fungal pathogens among isolated rhizobacteria. The dry weight of forage shoots and roots cultivated in unrepeated cultivation soils was higher than that cultivated in repeated cultivation soils. The dry weight of forage was positively affected by the inoculation of the antagonistic bacterium, Bacillus subtilis, in both repeated cultivation soils and unrepeated cultivation soils. In conclusion, the growth of forage was more affected by the inoculation of the antagonistic bacterium in unrepeated cultivation soils than that in repeated cultivation soils, and bacterization of forage with B. subtilis resulted in an inrreased yield.

• Proceedings of the Microbiological Society of Korea Conference
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• 2001.11a
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• pp.157-163
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• 2001

Mycolic acid-containing gram-positive bacteria, so called nocardioform actinomycetes, have become a great interest to environmental microbiologists due to their metabolic versatility, multidegradative capacity and potential for bioremediation of priority pollutants. For example, Rhodococcus rhodochrous N75 was able to metabolize 4-methy1catechol via a modified $\beta$-ketoadipate pathway whereby 4-methylmuconolactone methyl isomerase catalyzes the conversion of 4-methylmuconolactone to 3-methylmuconolactone in order to circumvent the accumulation of the 'dead-end' metabolite, 4-methylmuconolactone. R. rhodochrous N75 has also shown the ability to transform a range of alkyl-substituted catechols to the corresponding muconolactones. A novel 3-methylmuconolactone-CoAsynthetase was found to be involved in the degradation of 3-methylmuconolactone, which is not mediated in a manner analogous to the classical $\beta$-ketoadipate pathway but activated by the addition of CoA prior to hydrolysis of lactone ring, suggesting that the degradative pathway for methylaromatic compounds by gram-positive bacteria diverges from that of proteobacteria. Mycobacterium sp. Strain PYR-l isolated from oil-contaminated soil was capable of mineralizing various polyaromatic hydrocarbons (PAHs), such as naphthalene, phenanthrene, pyrene, fluoranthrene, 1-nitropyrene, and 6-nitrochrysene. The pathways for degradation of PAHs by this organism have been elucidated through the isolation and characterization of chemical intermediates. 2-D gel electrophoresis of PAH-induced proteins enabled the cloning of the dioxygenase system containing a dehydrogenase, the dioxygenase small ($\beta$)-subunit, and the dioxygenase large ($\alpha$)-subunit. Phylogenetic analysis showed that the large a subunit did not cluster with most of the known sequences except for three newly described a subunits of dioxygenases from Rhodococcus spp. and Nocardioides spp. 2-D gel analysis also showed that catalase-peroxidase, which was induced with pyrene, plays a role in the PAH metabolism. The survival and performance of these bacteria raised the possibility that they can be excellent candidates for bioremediation purposes.