• 생명과학회지
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• 제10권6호
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• pp.558-563
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• 2000

Effect of inhibitors on Vibrio parahaemolyticus cell growth and its urease activity was studied. The growth of the bacterium and the enzyme activity were inhibited by the addition of 0.02% p-hydroxymercuric benzoate, $HgCl_2$and $AgNO_3$. However, same concentration of boric acid, thallium acetate and $Pb(NO_3)_2$ did not affect the cell growth but inhibited urease activity by 25%, 29%, and 38%, respectively. Acetohydroxamic acid was the most potent inhibitor on cell growth by inhibiting 40% but did not affect urease activity. To investigate the effect of inhibitors on urease activity, urease was purified and confirmed on SDS-PAGE. The purified urease was inhibited 100% by the addition of 1 mM acetohydroxamic acid and $AgNO_3$but no inhibition was occurred by the addition of the same concentration of thallium acetate. and the addition of 0.01 mM of $HgCl_2$ and acetohydroxamic acid inhibited the purified urease activity by 39% and 24%, respectively. On 0.1 millimolar basic, acetohydroxamic acid and $HgCl_2$inhibited 4 times more active in urease inhibition than p-hydroxymercuric benzoate whereas no inhibition was occurred either thallium acetate or $Pb(NO_3)_2$.

• Journal of Microbiology and Biotechnology
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• 제12권4호
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• pp.610-616
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• 2002

The growth-inhibiting effects of Pinus densiflpora leaf-derived materials on nine human intestinal bacteria were investigated using the impregnated paper disk method, and their activities were compared with those of 13 commercially available terpenes. The biologically active constituent of the extract of P densiflora leaf was characterized as the monoterpene (1R)-(+)-$\alpha$-pinene by various spectroscopic analyses. Responses varied according to bacterial strain, chemicals, and dose. At 10 mg/disk, limonene and (1R)-(+)-$\alpha$-pinene strongly inhibited the growth of Clostridium perfringens, Staphylococcus aureus, and Escherichia coli, without adverse effects on the growth of five lactic acid-bacteria (Bifidobacterium adolescentis, B. bifidum, B. longum, Lactobacillus acidophilus, and L. casei). Little or no inhibition against seven bacteria was observed with anethole, borneol, camphor, caryophyllene, 1,8-cineole, estragole, linalool, and $\alpha$-terpineol. Structure-activity relationship revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S-(-)-$\alpha$-, and (1S-(-)-$\beta$-pinenes. Furthermore, the growth-inhibition against L. casei was much more pronounced in (1R)-(+)-$\beta$- and (In-(-)-$\beta$-pinenes than (1R)-(+)-$\alpha$- and (1S)-(-)-$\alpha$-pinenes. These results indicate that the (+)-$\alpha$ form seems to be required against C. perfringens and $\beta$ form against L. casei for growth-inhibiting activity. Morphologically, most strains of C. perfringens were damaged and disappeared at 5 and 2 mg/disk of (1R)-(+)-$\alpha$-pinene. Morphological study revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S)-(-)-$\alpha$-, and (1S)-(-)-$\beta$-pinenes. As naturally occurring growth-inhibiting agents, the Pinus leaf-derived materials described above could be useful preventive agents against diseases caused by harmful intestinal bacteria such as clostridia.

• 한국미생물·생명공학회지
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• 제49권3호
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• pp.374-383
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• 2021

Rhizoctonia solani is one of the major pathogens that cause sheath blight disease in rice. Sheath blight is one of the most difficult diseases to control. Biological control (with the use of rhizobacteria) is one of the ways to control this disease. Plant Growth Promoting Rhizobacteria (PGPR) is a rhizosphere bacterium that can be used to enhance plant growth. The composition of the rhizobacteria in organic and nonorganic soil is affected by the chemical characteristics of the soil - which influences plant physiology and root exudation patterns. This study aimed to obtain a species of rhizobacteria which shows PGPR activity, from organic and nonorganic rice fields and test their capability to suppress R. solani growth. Out of 23 isolates screened for PGPR activity, the following isolates showed high PGPR activity and were selected for in vitro antagonistic activity testing against R. solani: ISO6, ISO11, ISO15, ISN2, ISN3, and ISN7, The six isolates produced 43,42-75,23 ppm of IAA, possessed phosphorus solubilization capability, and chitinase-producing activity. ISO6 (54.88%) and ISN7 (83.33%) displayed high inhibition capacities against R. solani, in vitro. ISO6 and ISN7 inhibited the growth of R. solani lesions on rice leaves by 89% and 100% (without lesion), respectively, after 7 days of incubation. Analysis of their 16S rRNA sequences revealed that the ISO6 isolate was Citrobacter freundii and ISN7 isolate was Pseudomonas aeruginosa.

• 한국환경교육학회지:환경교육
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• 제24권4호
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• pp.32-40
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• 2011

The purpose of this study was to develop an evaluation standard by which teachers in charge of environment and green growth education could conduct a project activity and examine its applicability. The results were as follows; First, 26 evaluation items were developed through interviews with teachers and expert meetings. These categories were base on 'Theme', 'Planning', 'Result' and 'Presentation', and 'Evaluation' of the project. Second, a reliability test showed that internal consistency of the items was currently high(Cronbach's alpha .8709). To examine the content validity, the project activity was evaluated by 5 different teachers, and the result showed that the evaluation standard developed in this study was a very effective tool for the teachers to do project learning. Third, from the 2011 revised national curriculum, the subject 'Environment' in middle schools would be renamed as 'Environment and Green Growth'. Also, environment project activity would be introduced in the middle school. Therefore, this study had a significant importance in the fact that it provided teachers and students with a practical evaluation standard for the environment and green growth project activity.

• 한국환경농학회지
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• 제16권3호
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• pp.269-273
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• 1997

천연의 (S)-(+)-ABA 보다 우수한 생육저해 활성을 갖는 ABA 유도체를 개발하기 위한 연구의 일환으로 p-hydroxy methyl cinnamate와 umbelliferone을 (S)-(+)-2-cis, 4-trans-ABA에 ester 결합시켜서 ABA-methyl cinnamate ester(AC)와 ABA-umbelliferone ester(AU) 화합물을 각각 83%와 78%의 높은 수율로 얻었다. 이들의 벼 유묘 생육저해 활성은 (+)-ABA에 비해서 AC가 $3{\sim}10$배, AU가 $10{\sim}30$배 정도로 훨씬 더 강한 활성을 보였다.

• 미생물학회지
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• 제13권1호
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• pp.31-36
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• 1975

Chlorella ellipsoidea cells were cultured in a phosphate, magnesium, sulfur or potassium-free medium. Some portions of cells were taken out at intervals during the culture, and physiological activities such as growth rate, reproduction, photosynthetic activity, and biosynthesis of cholorophyll of macro-element deficient cells were measured. 1) Generally, growth rate, reproduction, photosynthetic activities, and biosynthesis of chlorophyll of the macro-element deficient cells decreased more or less, compared with those of the normal cells. 2) The growth and reproduction of the algal cells in sulfur, or magnesium free medium were retarted severely with the chlorosis ; the photosynthetic activity and the content of chlorophyll showed the same tendency. 3) It is considered that the decrease in growth rate of macro-element deficient Chlorella cells is due to the decrease in photosynthetic activity owing to the decrease in chlorophyll content of the cells.

• 한국식품위생안전성학회지
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• 제8권3호
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• pp.141-145
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• 1993

수종의 병원성 미생물에 대한 39여종의 생약 열수추출액의 항균성을 조사한 결과 다음과 같은 결과를 얻었다. 황백 Phellodendron amurense 및 황령 Coptis chinensis 는 Staphylococcus aureus균의 생육을 억제시켰으며 복분자 Rubus creanus는 Staphylococcus aureus 및 Pseudomonas aeruginosa에 항균력을 나타내었다. 진피 Citrus unshiu는 E.coli에 대해서 산수유 Cornus officinalis는 Candida albicans의 생육을 억제시켰고 우슬 Achyranthes japonica 및 감초 Clycyrrhiza uralsis는 Aspergillus niger에 뚜렷한 항균효과를 나타내었다. 또한 감초는 Staphylococcus Aureus, E. coli, Pseudomonas aeruginosa , Aspergillus niger 모두에 항균력을 나타내었다.

• 한국축산식품학회지
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• 제28권1호
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• pp.105-108
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• 2008

The cell growth and antioxidant activity of Bacillus polyfermenticus SCD were studied in tryptic soy broth (TSB) medium and whey protein concentrate (WPC)-based medium. Overall, higher lactose contents in WPC-35 medium (up to 2.0%), and longer culture times correlated with greater cell viability. In WPC-35 medium with 1.5% and 2.0% lactose, the cell growth of B. polyfermenticus SCD was similar to growth in TSB medium. The 1,1-diphenyl-2-picyrylhydrazyl (DPPH) radical scavenging activity of culture supernatant of B. polyfermenticus SCD in WPC-35 medium was measured to assess antioxidant activity. The antioxidant activity increased up to 32 hr of culture, reaching a maximum of 75.57% DPPH radical scavenging activity. The antioxidant activity seemed to follow the typical kinetics of primary metabolite synthesis. The antioxidant activity of B. polyfermenticus SCD supernatant in WPC-35 medium was more effective and stable than supernatant from TSB medium. These results suggest that WPC-35 medium is effective for the production of antioxidant by B. polyfermenticus SCD.

• Journal of Microbiology and Biotechnology
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• 제17권8호
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• pp.1300-1307
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• 2007

This study assessed the possible role of different traits in selected plant growth-promoting rhizobacteria (PGPR) for improving wheat growth and yield under natural conditions. Rhizobacteria exhibiting 1-aminocyclopropane-1-carboxylate (ACC)-deaminase activity were isolated and screened for their growth-promoting activity in wheat under axenic conditions. Five isolates belonging to Pseudomonas and one Burkholderia caryophylli isolate that showed promising performances under axenic conditions were selected and characterized for in vitro ACC-deaminase activity, chitinase activity, auxin production, P solubilization, and root colonization. These isolates were then used as inocula for wheat cultivated under natural conditions in pot and/or field trials. Significant increases in root elongation, root weight, tillers per pot, 1,000-grain weight, and grain and straw yields were observed in response to inoculation with PGPR in the pot trials. Inoculation with these PGPR was also effective under field conditions and increased the wheat growth and yield significantly. However, the efficacy of the strains was inconsistent under the axenic, pot, and field conditions. Pseudomonas fluorescens ($ACC_{50}$), which exhibited a relatively high in vitro ACC-deaminase activity, chitinase activity, auxin production, and P solubilization and more intensive root colonization, was the most efficient isolate under the field conditions. Therefore, these results demonstrated that ACC-deaminase activity is an efficient parameter for the selection of promising PGPR under axenic conditions. However, additional traits of PGPR, including auxin production, chitinase activity, P solubilization, and root colonization, are also important for selecting PGPR as biofertilizers.

• 한방안이비인후피부과학회지
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• 제22권1호
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• pp.1-10
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• 2009

Objectives : To investigate the effects of DL-HGF to hair growth activity in mouse, various kinds of ethosome and liposome formulations entrapped DL-HGF were produced and this study was carried out. Methods : The B16/BL6 mice were classified into five groups: vehicle control (Con) group, Et-1-applied group, Et-2-applied group, LP-1-applied group, LP-2-applied group. Active hair growth (anagen) was induced in the back skin by application of a waxosin mixture with subsequent depilation and the activity of hair growth was measured by macroscopic observation and histology. Results : In vehicle control group, there was no hair growth activity during experiment period. In Et-1-applied group, the rate of hair growth was about 100%, LP-1-applied group and Et-2-applied group showed 70-80% and 40-50% of hair growth rates, respectively. The rate of hair growth of LP-2-applied group was lower than other applied groups (20-30%). In H/E staining, Numerous hair folicles and hair shafts were observed in Et-1-applied group and other groups showed lower level of hair folicles and hair shafts formation than Et-1-applied group, Conclusion : Et-1 formulation showed highest hair growth activity than other ethosome and liposome formulations entrapped DL-HGF.