• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1568-1572
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• 2007

To develop a natural fungicide against Botrytis cinerea and Colletotrichum gloeosporioides, a total of 25 essential oils were tested for their fumigant activity against post-harvest pathogens. The vaporous phases of oils were treated to each fungus on potato dextrose agar medium in half-plate separated Petri plates at $10\;{\mu}g$ per plate. The essential oil of Illicium verum strongly inhibited the mycelial growth of both B. cinerea and C. gloeosporioides by over 90%. On the other hand, the essential oil of Schizonepeta tenuifolia showed inhibitory activity against mycelial growth of only B. cinerea by over 90%. Gas chromatography-mass spectrometry and bioassay indicated trans-anethole in I. verum and menthone in S. tenuifolia as a major antifungal constituent. The essential oils of I. verum and S. tenuifolia and their major constituents could be used to manage post-harvest diseases caused by B. cinerea and C. gloeosporioides.

• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.864-871
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• 2013

The recombinant strain P. pastoris GS115-lccC was used to produce laccase with high activity. Factors influencing laccase expression, such as pH, methanol concentration, copper concentration, peptone concentration, shaker rotate speed, and medium volume were investigated. Under the optimal conditions, laccase activity reached 12,344 U/L on day 15. The recombinant enzyme was purified by precipitating and dialyzing to electrophoretic homogeneity, and was estimated to have a molecular mass of about 58 kDa. When guaiacol was the substrate, the laccase showed the highest activity at pH 5.0 and was stable when the pH was 4.5~6.0. The optimal temperature for the laccase to oxidize guaiacol was $60^{\circ}C$, but it was not stable at high temperature. The enzyme could remain stable at $30^{\circ}C$ for 5 days. The recombinant laccase was used to degrade chlorpyrifos in several laccase/mediator systems. Among three synthetic mediators (ABTS, HBT, VA) and three natural mediators (vanillin, 2,6-DMP, and guaiacol), vanillin showed the most enhancement on degradation of chlorpyrifos. Both laccase and vanillin were responsible for the degradation of chlorpyrifos. A higher dosage of vanillin may promote a higher level of degradation of chlorpyrifos, and the 2-step addition of vanillin led to 98% chlorpyrifos degradation. The degradation of chlorpyrifos was faster in the L/V system ($k_{obs}$ = 0.151) than that in the buffer solution ($k_{obs}$ = 0.028).

• Journal of Plant Biotechnology
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• v.5 no.1
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• pp.33-41
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• 2003

Microspore-derived cell lines resistant to 5-methyltryptophan (5MT, a tryptophan analog) or S-(2-aminoethyl)-L-cysteine (AEC, a Iysine analog) were selected in rice by in vitro mutagenesis. For selection of 5MT or AEC resistant cell lines, suspension-cultured cells were irradiated with gamma rays. Thirteen 5MT resistant cell lines were selected and they were able to grow stably at 2 times higher 5MT concentration. A feedback insensitive form of anthranilate synthesis, the pathway specific control enzyme for tryptophan synthesis, was detected from the 5MT resistant lines. Contents of the free amino acids in five resistant lines (MR12-1 to MR12-5) showed a 7.4 to 46.6 times greater level than that in the control culture. Tryptophan, phenylalanine, and tyrosine levels in the shikimate pathway were 28.1 and 22.5 times higher in MR12-3 and MR12 4, respectively, than that measured in the control cells. Four AEC resistant cell lines were isolated from cultures grown on medium containing 1 mM AEC, They were able to grow stably with 2 mM AEC, while sensitive calli were inhibited by 0.5 mM AEC. Aspartate kinase activities of the resistant lines were insensitive to the natural inhibitor, Iysine, and accumulated 2.2 to 12.9-fold higher levels of free Iysine than that of the control cells. Especially, the levels of aspartate, asparagine, and methionine in the aspartate pathway showed higher accumulation in the AEC resistant lines than that in the control cells.

• Research in Plant Disease
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• v.12 no.1
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• pp.46-50
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• 2006

The microorganisms with the antifungal activity against Phytophthora capsici and Colletotrichum acutatum and the plant growth-promoting activity were screened from a forest and natural fields of Gajang-Dong, Sangju-city. One of the isolates, Streptomyces griseofuscus 200401, was selected as a good plant growth-promoting strain in this study. In greenhouse test, the number of leaf, fresh weight, and dry weight of pepper plants, that were grown with treatment of culture suspension or powder containing S. griseofuscus 200401, were higher than those without the bacterial cells. Cultivation of S. griseofuscus 200401 strain for 7 days in a nutrient rich medium produced ammonium chloride up to 0.13 ${\mu}g/ml$ in the culture solution of S. griseofuscus. Treatment of the selected strain significantly reduced the severity of the late blight of pepper plants to show the equivalent disease control activity to chemical fungicide. This study suggests that S. griseofuscus 200401 strain could be a potential biological agent with the biocontrol activity and the plant growth-promoting activity.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.47-55
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• 2015

Recently, the production of taste and odor (T&O) compounds is a common problem in water industry. Geosmin is one of the T&O components in drinking water. However, geosmin is hardly eliminated through the conventional water treatment systems. Among various advanced processes capable of removing geosmin, adsorption process using granular activated carbon (GAC) is the most commonly used process. As time passes, however GAC process changes into biological activated carbon (BAC) process. There is little information on the BAC process in the literature. In this study, we isolated and identified microorganisms existing within various BAC processes. The microbial concentrations of BAC processes examined were $3.5{\times}10^5$ colony forming units (CFU/g), $2.2{\times}10^6CFU/g$ and $7.0{\times}10^5CFU/g$ in the Seongnam plant, Goyang plant and Goryeong pilot plant, respectively. The dominant bacterial species were found to be Bradyrhizobium japonicum, Novosphingobium rosa and Afipia broomeae in each plants. Removal efficiencies of $3{\mu}g/L$ geosmin by the dominant species were 36.1%, 36.5% and 34.3% in mineral salts medium(MSM) where geosmin was a sole carbon source.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.81-88
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• 1985

A potential lipid producing strain of Penicillium sp. was isolated from natural source. Penicillium sp. was cultivated in an appropriate medium containing 6% of glucose as a corbon source, ammonium nitrate as a nitrogen source, C:N ratio 200, pH 4.0 for a period of 17 days at $35^{\circ}C$. Under the condition, the lipid content was 64.2% of dry cell weight. The total lipid produced was 13.7g/100g of glucose consumed. The proportion of nonpolar and polar lipid fractions was 92.2% and 7.8%, respectively. The nonpolar lipid compositions of lipid produced under optimum condition were 5.3% of free fatty acids, 6.8% of free sterols, 9.3% of partial glycerides and 72.0% of triglycerides. The major fatty acids of total lipid were 20.1% of palmitic acid, 21.6% of linoleic acid and 53.3% of oleic acid.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.173-177
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• 1997

Bacillus licheniformis 9945a releases a natural ${\gamma}-poly(glutamic\;acid)({\gamma}-PGA)$ into fermentation broth and shows a mucoid phenotype on the solid agar medium. Transformation of mucoid cells of Bacillus species has not been simple and straightforward. The transpositional activity of Tn10 in B. licheniformis also has not been own either. Thus, a spontaneous non-mucoid derivative of the B. licheniformis was obtained first. Shuttle vector pHV1248 containing mini-Tn10 was introduced into the non-mucoid derivative by the method of protoplast transformation. The resulting transformant was reverted to the wild mucoid phenotype, and then mutated randomly with the mini-transposon by heat induction. Auxotrophs requiring arginine, lysine, or tryptophan were isolated by replica plating method. Southern blotting and DNA-DNA hybridzation analysis showed that these auxotrophs were generated by mini-Tn10 insertion into the chromosomal DNA. This method of transformation and mutation using pHV1248 would be useful for the generation of diverse mutants of B. licheniformis 9945a.(Received January 24,1997; accepted March 10, 1997)

• Journal of the Mineralogical Society of Korea
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• v.2 no.1
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• pp.26-36
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• 1989

Clinopyroxene in the Geodo mine belongs to diopside-hedenbergite series. It is widely distributed throughout the mine area together with garnet and is also closely related with Fe-mineralization. Clinopyroxenes in the Geodo mine including two samples from the sangdong and Ulchin Mines are studied using polarized microscope, EPMA, XRD, and IR spectroscopy for occurrence, chemistry, structure, and crystal chemistry. Especially, variations in unit-cell parameters are examined in relation with the substitution scheme between Fe and Mg cations. Clinopyroxenes in the Geodo mine occur in both endoskarn and exoskarn zone. It is mostly anhedral to subhedral with fine- to medium-grained in texture, but some have bigger crystals of short prismatic or columnar habits. Clinopyroxene occurs as monomineralic or is associated with mostly garnet and sometimes with actinolite, magnetite, epidote, and chlorite. Chemical analysis reveals that the Geodo clinopyroxene is diopsidic in composition (Di: 65-96%). This fact is in good contrast with garnet chemistry showing mostly andraditic (An: 41-82%). Especially, clinopyroxene coexisting with magnetite belongs to nearly end member diopside (Di: 97-99%). Thus, diopside-andradite pair indicates that Geodo skarns were formed under the reduced environment. X-ray diffraction analysis shows unit-cell parameters vary with increase of Fe contents: a = 9.765-9.838$\AA$, b = 8.943-9.020$\AA$, c= 5.240-5.253$\AA$.$\beta$ = 105.70-104.83$^{\circ}$, and V =440.64-448.19$\AA$3. It is noted from the least square regression that a, b and V increase linearly with increase of Fe content, while $\beta$ slightly decreases and c remains nearly unchanged as change in Fe content. These trends are to difference between synthetic and natural clinopyroxenes. This fact is also recognized in IR spectra which show a slight shift of several absorption bands toward lower wavenumber region with increasing Fe content.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.201-210
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• 2011

This experiment was conducted to investigate physical and chemical characteristics by volume fractions of root media using peatmoss, perlite, and vermiculite, along with effects on the growth of pot chrysanthemums (Dendranthema ${\times}$ grandiflorum 'Vemini') in a C-channel mat irrigation system. To evaluate the physico-chemical properties of 20 root media, the bulk density, particle density, total pore space, pore space, ash content, organic matter, pH, and electrical conductivity were measured and data were analyzed using principal component analysis (PCA). PCA scores revealed that physico-chemical properties changed by the blending of peatmoss, perlite, and vermiculite. The 20 root media were divided into three main groups by hierarchical cluster analysis. At the end of the experiment, the pH and EC of the root media were measured from media divided into four layers. The pH of root media without plants showed a strong linear relationship and the pH of root media with plants increased exponentially. The change of EC in the root medium was indicated as a hyperbolic curve. Plant growth characteristics according to growth in the 20 root media were analyzed by PCA. It was found that the mixing ratios of the root media affected plant growth characteristics. Therefore, mixing ratio is an important factor for pot-plant production in a subirrigation system.

• Archives of Reconstructive Microsurgery
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• v.22 no.1
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• pp.18-23
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• 2013

Purpose: For reconstruction of lower extremity defects, various flaps can be used and the appropriate flap must be selected and applied according to the size of the defect. In particular, in cases where the defect size is small to moderate, thinner or smaller volume flaps are useful. The authors performed reconstruction of small to moderate defects on the lower extremities using superficial circumflex iliac artery perforator free flaps and are reporting the results. Materials and Methods: Fifteen patients underwent reconstruction of defects on lower extremity areas using superficial circumflex iliac artery perforator free flaps from July 2011 to July 2012 at this hospital. The flaps were elevated from above the deep fat layer, and, in all cases, the vessel diameter of the flaps was less than 1mm, with the exception of superficial vein that accompanied it. Results: The mean follow up period was 4.46 months, and, despite a partial loss in the flap in two cases, there were no total losses. All donor sites were closed with primary closure, and there was no occurrence of complications, such as hematomas, seromas, or lymphorrheas. The patients were highly satisfied with the donor site scar since it could be masked by underwear. Conclusion: Compared to other flaps, superficial circumflex iliac artery perforator free flaps are thinner in thickness and smaller in volume, which results in a more natural contour of the recipient site after the operation. In addition, since the flap can be elevated from supra-deep fat layer, the operation time can be shortened, and lymphorrhea can be prevented, which in turn lessens donor-site morbidity.