• Journal of Microbiology
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• 제41권4호
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• pp.271-276
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• 2003

The inoculation of some microorganisms into a microcosm containing soil from a barren lakeside area at Lake Paro in Kangwon-do enhanced plant growth significantly. The direct and viable counts of soil bacteria and soil microbial activities measured by electron transport system assay and fluorescein diacetate hydrolysis assay were higher in inoculated soil. The plant growth promoting effect of this inoculation may be caused by phytohormone production and the solubilization of insoluble phosphates by the inoculated bacteria. Three inoculated strains of Pseudomonas fluorescens produced several plant growth promoting phytohormones, including indole-3-acetic acid (auxin), which was confirmed by thin layer chromatography and GC/MS. P. fluorescens strain B16 and M45 produced 502.4 and 206.1 mg/l of soluble phosphate from Ca3(PO4)2 and hydroxyapatite, respectively. Bacillus megaterium showed similar solubilization rates of insoluble phosphates to those of Pseudomonas spp. We believe that this plant growth promoting capability may be used for the rapid revegetation of barren or disturbed land.

• Bulletin of the Korean Chemical Society
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• 제27권7호
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• pp.991-994
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• 2006

Herein, insoluble single-walled carbon nanotube (SWNT) was successfully dispersed into water in the presence of a special kind of surfactant-dicetyl phosphate (DCP), subsequently, a SWNT-DCP composite film coated glassy carbon electrode (GCE) was fabricated. The electrochemical behaviors of 6-benzylaminopurine (6-BAP) at the unmodified GCE and SWNT-DCP modified GCE were examined. It is found that the SWNT-DCP modified GCE remarkably enhances the oxidation peak current of 6-BAP, indicating great potential in the determination of trace level of 6-BAP. Finally, a sensitive and simple voltammetric method with a good linear relationship in the range of ${\times}5.0\;\;10^{-8}\sim 2.5\;{\times}\;10^{-6}$ mol/L, was developed for the determination of 6-BAP. The detection limit is as low as $2.0\;{\times}\;10^{-8}$ mol/L for 3-min accumulation. This newly-proposed method was successfully demonstrated with practical samples.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.321-322
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• 2009

산화마그네숨을 주성분으로 하고 있어 시멘트 고화로 문제가 되는 육가 크롬을 포함하지 않을 뿐만 아니라 시멘트, 석회류와 마찬가지로 내구성이 있는 경화물이 생성되기 때문에 불용화 처리 효과의 장기 안정성이 우수하며 인산염 시멘트의 압축강도는 $21^\sim$28MPa로서 포틀랜드 시멘트와 비교할만하다. 본 연구에서는 이러한 인산염 마그네시아의 특성을 이용하여 중금속인 Cr과 Pb의 고용화 적용 가능성을 실험하였으며, 중금속 이온과 마그네시아 시멘트에 의한 고용체의 생성 및 고정화 된 고용체에 서의 중금속 이온의 용출특성을 검토 하였다.

• 한국토양비료학회지
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• 제28권3호
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• pp.278-286
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• 1995

토양(土壤)에 축적(蓄積)되어 있는 난용성(難溶性) 인산염(燐酸鹽)을 이용(利用)하고자 인산염(燐酸鹽) 가용화능(可溶化能)을 가지고 있는 Pseudomonas putida, Penicillium속(屬) 및 Aspergillus niger를 우리 나라 주요(主要) 경작지(耕作地) 토양(土壤)에서 분리(分離)하여 이들 균(菌)의 용해능(溶解能)을 측정(測定)하였다. 인산염(燐酸鹽) 용해량(溶解量)은 배지내(培地內)의 pH 저하(低下)와 밀접(密接)한 관계(關係)를 가지고 있었다. Pseudomonas putida, Penicillium속(屬)에 비(比)해 Aspergillus niger의 인산염(燐酸鹽) 가용화능(可溶化能)이 높았다. Aspergillus niger에 의한 인산염(燐酸鹽) 종류별(種類別) 최대(最大) 가용화량(可溶化量)은 질소원(窒素源)이 $KNO_3$일 때는 aluminium phosphate 776ppm, hydroxyapatite 665ppm, tai-calcium phosphate 593ppm이었으며 인광석(燐鑛石)은 질소원(窒素源)이 $(NH_4)_2SO_4$일 때 411ppm이었다.

• 한국토양비료학회지
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• 제17권1호
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• pp.39-45
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• 1984

수도체(水稻體)가 감수분열기(減數分裂期) 및 츨수기(出穗期)에 저온(低溫)이 되었을 때 엽면시비(葉面施肥)된 인산(燐酸)이 식물체내(植物體內)로 침투(浸透)되는지의 여부(與否)와 침투(浸透)된 인산(燐酸)이 이삭으로 이동(移動)되어 어떠한 형태(形態)의 인산(燐酸)으로 곡립(穀粒)에 존재(存在)하는지를 알기 위해 상온(常溫)에서 생육(生育)한 벼와 저온처리(低溫處理)한 수도체(水稻體)를 상호비교(相互比較)하여 시험(試驗)을 실시(實施)한 결과(結果) 아래와 같이 요약(要約)되었다. 1. 감수분열기(減數分裂期) 및 출수기(出穗期) 수도(水稻)에 엽면시용(葉面施用)한 $^{32}P$ 혼합(混合) 인산용액(燐酸溶液)은 식물체내(植物體內)로 쉽게 흡수이용(吸收利用)되었고 상온(常溫)($25^{\circ}C$)에서 더 잘 흡수(吸收)되나 저온(低溫)($17^{\circ}C$)처리(處理) 수도체(水稻體)에서도 상당량(相當量)이 흡수(吸收)되었다. 2. 엽면시용인산(葉面施用燐酸)은 지엽(止葉)과 같은 신전개엽(新展開葉)일수록 잘 흡수(吸收)되며 노화(老化)된 잎일수록 흡수정도(吸收程度)가 낮았다. 3. 엽면흡수(葉面吸收)된 인산(燐酸)은 대부분(大部分)이 곡실(穀實)로 이동(移動)하여 현미(玄米)에 집적(集積)되며 다른 이삭으로도 전류(轉流)되었다. 4. 곡립(穀粒) 중(中) 인산형태(燐酸形態)를 조사(調査)한 결과(結果) 상온(常溫)에서 생육(生育) 수도체(水稻體)에서는 TCA에 가용(可溶)이고 Ba에 불용(不溶)인 인산(燐酸)이 대부분(大部分)이어서 주(主)로 저장태(貯藏態) 인산(燐酸)인 phytin태(態)로 존재(存在)하였다. 5. 저온처리(低溫處理)를 받은 수도체(水稻體)에서는 Ba가용(可溶)EtOH 불용(不溶)인 당인산태(糖燐酸態)가 가장 많고 그 다음으로 lipid-P가 증가(增加)하였다.

• 한국토양비료학회지
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• 제40권6호
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• pp.442-446
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• 2007

토양에 고정되어 축적된 난용성 인산염을 가용화하는 유용세균을 선발하여 생물비료로 이용하고자 고추, 토마토, 상추, 오이, 목초, 잔디의 근권토양 및 뿌리표면에서 인산가용화능이 있는 세균을 분리하였다. 선발된 인산가용화균은 16S rRNA 염기서열과 생화학적특성 등에 의해 동정되었으며, 난용성인산 가용화기능이 우수한 세균 Pseudomonas sp. CL-1 및 Kluyvera sp. CL-2균주를 선발하였다. Pseudomonas sp. CL-1균주는 esculin과 gelatin, casein을 가수분해하였고, 그리고 glucose, arabinose, mannose, mannitol, N-acetyl-glucosamine, gluconate, caprate, adipate, malate, citrate 등을 이용하였다. Kluyvera sp. CL-2 균주는 esculin과 CM-cellulose를 가수분해 하였고 acetoin을 생성하였다. 그리고 glucose, arabinose, mannose, mannitol, N-acetyl-glucosamine, maltose, gluconate, malate, citrate 등을 이용하였다. Pikovskaya's medium에서 선발균주의 난용성인산 $Ca_3(PO_4)_2$의 인 가용화량을 정량한 결과 Pseudomonas sp. CL-1과 Kluyvera sp. CL-2 균주는 접종후 1일, 3일에 각각 148.0, $193.4(P\;mg\;L^{-1})$와 482.8 mg, 493.6 mg의 인 가용화량을 나타내었다

• 미생물학회지
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• 제8권1호
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• pp.1-12
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• 1970

Nucleic acid and protein biosynthese of the glucose-bleached Chlorella cells in relation to the process of the chloroplast reformation were traced, by measuring the changes in the amounts of cell constituents and nuclease activities of the cells during the greening process. The contents of RNA and protein of the glucose-bleached cells decreased significantly, shile the contents of nucleotides and amino acids of the cells increased to compared with those of the control, showing that the biosynthetic activities of RNA and protein of the cells were inhibited severely in the glucose-bleaching process. In the early greening process of the glucose-bleached Chlorella cells the contents of RNA and protein of the cells increased significantly, while the contents of nucleotides nad amino acids of the cells increased to compared with those of the control, showing that the biosynthetic activities of RNA and protein of the cells were inhibited severely in the glucose-bleaching process. In the early greening process of the glucose-bleached Chlorella cells the contents of RNA and protein of the cells increased significantly wihout any increase in the chlorophyll contents showing that the massive biosynthese of RNA and protein proceed prior to the chlorophyll bioynthesis in the cells. The phosphate contents in the DNA fraction of the glucose-bleached cells decreased, but the contents of acid-insoluble polyphosphate increased to compared with those of the control in the early greening porcess, exhibiting that the incorporation of the phosphorus from acid-insoluble polyphosphate into DNA was retarded. In the greening process of the glucose-bleached cells the ribonuclease nad deoxyribonuclease activities of the cells decreased to compared with those of the control, although the initial activities of the both enzymes in the cell were far great compared with the control. Although the initial phosphate contents in the lipid fraction of the glucose-bleached Chlorella cells were more great than the control, the phosphate contents in the lipid fraction of the cells decreased in the early greening process to compared with control, and then increased in the late developmental stages in which massive chlorophyll biosynthesis occured.

• 한국토양비료학회지
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• 제45권2호
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• pp.169-176
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• 2012

Among the major nutrients, phosphorus is by far the least mobile and available to plants in most soil conditions. A large portion of soluble inorganic phosphate applied to soil in the form of phosphate fertilizers is immobilized rapidly and becomes unavailable to plants. To improve the plant growth and yield and to minimize P loss from soils, the ability of a few soil microorganisms converting insoluble forms into soluble forms for phosphorus is an important trait in several plant growth-promoting microorganisms belonging to the genera Bacillus and Pseudomonas and the fungi belonging to the genera Penicillium and Aspergillus in managing soil phosphorus. The principal mechanism of solubilization of mineral phosphate by phosphate solubilizing bacteria (PSB) is the release of low molecular weight organic acids such as formic, acetic, propionic, lactic, glycolic, fumaric, and succinic acids and acidic phosphatases like phytase synthesized by soil microorganisms in soil. Hydroxyl and carboxyl groups from the organic acids can chelate the cations bound to phosphate, thereby converting it into soluble forms.

• 한국미생물·생명공학회지
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• 제26권4호
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• pp.365-368
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• 1998

The aklavinone 11-hydroxylase which was overexpressed using T7 promoter in E. coli could be detected in SDS-PAGE only in insoluble precipitate without any detectable enzyme activity. The insoluble enzyme was solubilized in 6M guanidine$.$HCl solution and their refolding ability was tested under various conditions. When the enzymatic activity was checked by the bioconversion experiment, stepwise dialysis against 6M, 3M, 1M guanidine$.$HCl and finally 100 mM potassium phosphate buffer of the solubilized protein gave the best bioconversion efficiency. The aklavinone 11-hydroxylase showed its enzymatic activity in the reaction buffer containing NADPH with vigorous shaking. The enzymatic activity was lost during partial purification and regained by the addition of crude extract of S. lividans in the reaction mixture. This effect was confirmed to due to some low-molecular weight component(s) in the crude extract, because the addition of dialyzed crude extract could not recover the enzymatic activity.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.546-551
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• 2005

[ ${\beta}-1,3-Glucan$ ] (curdlan) is a water-insoluble polysaccharide composed exclusively of ${\beta}-1,3\;linked$ glucose residues. Extracellular curdlan was mostly synthesized by Agrobacterium species and Alcaligenes faecalis under nitrogen-limiting conditions. In this study, we screened the microorganisms capable of producing extracellular curdlan from soil samples. For the first time, we reported Gram-positive bacterium Bacillus sp. SNC 107 capable of producing extracellular curdlan in appreciable amounts. The effect of different carbon sources on curdlan production was studied and found that the yield of curdlan was more when glucose was used as carbon source. It was also found that maximum production was achieved when the initial concentration of ammonium and phosphate in the medium was 0.5 and 1.9 g/L respectively. In this study the curdlan production was increased from 3 to 7g/L in shake flask cultures.