• 자연과학논문집
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• 제12권1호
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• pp.69-79
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• 2002

PDA-calcium phosphate 평판배지를 이용하여 인산가용화활성을 가진 850종의 세균을 분리한 후 인광석에 대한 인산가용활성이 가장 강한 HS-2 균주를 선발하였다. 선정 균주의 형태학적, 배양학적 및 생리생화학적 특성 등을 조사한 결과 Azotobacter sp. HS-2로 동정되었고, 이 균주을 인광석을 0.1%함유한 Potato dextrose Broth배지 (pH 6.0)에 접종하여 $30^{\circ}C$에서 5일 배양했을 때 인광석이 가장 많이 분해되었고 0.5M의 수산을 첨가했을 때 분해율이 약 50% 증가되었다.

• 농업과학연구
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• 제49권3호
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• pp.463-481
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• 2022

Phosphorous (P) is considered to be one of the key essential elements demanded by crop plants. Approximately 70 - 90% of phosphatic fertilizers applied to crops are fixed in soil as Ca, Fe, and Al metal cations, which are insoluble and thus not readily available for plant uptake. Therefore, most soils are deficient in plant available P. This is usually rectified by applying phosphate fertilizers continuously, although this is not economically viable or environmentally acceptable. The present paper reviews the mechanisms involved with phosphate solubilization and mineralization by phosphate solubilizing microorganisms (PSMs) with the associated factors that determine the success. PSMs are effectively involved in mediating the bioavailability of soil P. Their contribution includes mineralization of organic P solubilization of inorganic P minerals, and storing sizable amounts of P in biomass through different mechanisms such as the production of organic and inorganic acids, H₂S, siderophores, exopolysaccharides, and production of enzymes such as phosphatases, phytase, and phosphonatases/C-P lyases, which are capable of chelating the metal ions, forming complexes, and making plant available P. PSMs manifest a wide range of metabolic functions in different environments, resulting in significantly higher plant growth, enhanced soil properties, and increased biological activities. Therefore, development of bio-inoculants with efficient novel PSM strains and further investigations on exploring such strains from diverse ecological niches with multifunctional plant-growth-promoting traits are needed.

• 한국균학회지
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• 제41권4호
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• pp.218-224
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• 2013

한국 전통 발효식품에서 분리한 효모로부터 인산 가용화 활성이 우수한 5균주를 선발하였다. 선발한 균주 중 2균주는 Pichia anomala로 동정되었고, 3균주는 각각 Pichia farinosa, Candida versatilis, Pichia subpelliculosa로 동정되었다. 인산 가용화 효모는 $20{\sim}35^{\circ}C$의 온도에서 잘 자라는 중 온성 효모였으며 P. farinosa Y669는 $45^{\circ}C$의 고온에서도 생장하였다. C. versatilis Y907 균주는 pH 5~6의 좁은 pH 범위에서 생장하였고 15%의 NaCl 농도까지 내성을 나타내는 호염성 균주였다. 그 외 4균주는 pH 4.0~8.0에서 생장하였으며 NaCl 10% 농도에서 내성을 나타내었다. 인산 가용화 균주는 토양에서도 8주 동안 $10^7{\sim}10^8$ cfu/g의 밀도를 유지하며 생존하였다. 분리균주 중 인산 가용화 활성은 P. subpelliculosa Y1101가 가장 우수하였으며 배양 11일 후 697.2 ug/mL의 유리인산을 생성하였다.

• Archives of Pharmacal Research
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• 제28권5호
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• pp.604-611
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• 2005

Polyethylene glycol (PEG) 6000-based solid dispersions (SDs), by incorporating various pharmaceutical excipients or microemulsion systems, were prepared using a fusion method, t o compare the dissolution rates and bioavailabilities in rats. The amorphous structure of the drug in SDs was also characterized by powder X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The ketoconazole (KT), as an antifungal agent, was selected as a model drug. The dissolution rate of KT increased when solubilizing excipients were incorporated into the PEG-based SDs. When hydrophilic and lipophilic excipients were combined and incorporated into PEG-based SDs, a remarkable enhancement of the dissolution rate was observed. The PEG-based SDs, incorporating a self microemulsifying drug delivery system (SMEDDS) or microemulsion (ME), were also useful at improving the dissolution rate by forming a microemulsion or dispersible particles within the aqueous medium. However, due to the limited solubilization capacity, these PEG-based SDs showed dissolution rates, below 50% in this study, under sink conditions. The PEG-based SD, with no pharmaceutical excipients incorporated, increased the maximum plasma concentration (C$_{max}$) and area under the plasma concentration curve (AUC$_{0-6h}$) two-fold compared to the drug only. The bioavailability was more pronounced in the cases of solubilizing and microemulsifying PEG-based SDs. The thermograms of the PEG-based SDs showed the characteristic peak of the carrier matrix around 60$^{\circ}C$, without a drug peak, indicating that the drug had changed into an amorphous structure. The diffraction pattern of the pure drug showed the drug to be highly crystalline in nature, as indicated by numerous distinctive peaks. The lack of the numerous distinctive peaks of the drug in the PEG-based SDs demonstrated that a high concentration of the drug molecules was dissolved in the solid-state carrier matrix of the amorphous structure. The utilization of oils, fatty acid and surfactant, or their mixtures, in PEG-based SD could be a useful tool to enhance the dissolution and bioavailability of poorly water-soluble drugs by forming solubilizing and microemulsifying systems when exposed to gastrointestinal fluid.

• 화훼연구
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• 제19권3호
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• pp.144-150
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• 2011

본 연구는 염류집적 국화 재배지 토양적응성 인산분해미생물 탐색하고 선발된 미생물 시용을 통한 염류집적 국화 재배지 토양에서의 토양 화학성의 변화를 조사하였으며 이를 통하여 염류집적 국화 재배지 토양 환경 개선 기술을 개발하고자 수행되었다. 시험에 사용된 인산분해미생물은 염류집적토양에서 분리된 Pseudomonas putida(KSJ11), Acinetobacter calcoaceticus (KSJ3) 및 Acinetobacter calcoaceticus (WP20) 3종류이었으며 미생물의 제형은 버미큘라이트에 혼합되어 있는 상용화된 제품을 이용하였다. 시험장소는 광주광역시 광산구 소재 신우화훼농장의 15년간 작물이 재배되어 염류집적현상이 나타나는 국화재배지에서 처리구 $82m^2$에 각각의 미생물 제재 250 L씩 시용하였다. 염류집적이 이루어진 국화재배온실에 처리된 인산분해미생물 Acinetobacter calcoaceticus(KSJ3; WP20)는 유효인산을 효율적으로 분해하는 것으로 나타났으며, 특히 Acinetobacter calcoaceticus(WP20)는 염류의 분해능력이 높았다. 인산분해미생물 시용에 따라 토양내 칼륨, 칼슘 및 마그네슘의 함량의 증가가 A. calcoaceticus(KSJ3; WP20)처리구에서 뚜렷하게 나타났으며 이러한 변화의 영향으로 판단되는 토양내 전기전도도도 증가되었다. 또한 인산분해미생물 시용은 선충밀도의 감소효과를 나타내어 토양환경개선을 위한 재료로 활용될 가능성을 나타내었다. 결과적으로 염류집적이 이루어진 국화재배 온실에서의 인산분해미생물 시용은 처리된 미생물의 종류에 따라 차이를 나타내었지만 토양의 유효인산량 증가와 양이온의 유용화에는 분명한 효과를 나타내었다. 따라서 염류집적 토양에서의 인산분해미생물 시용은 토양양분의 효율적인 사용을 가능하게 할 수 있는 방안이 될 수 있기 때문에 시비량 절감 등의 방법으로 활용할 수 있다고 판단되었다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1987년도 Proceedings of Korea-Japan Panax Ginseng Symposium 1987 Seoul Korea
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• pp.67-74
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• 1987

• Bulletin of the Korean Chemical Society
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• 제21권7호
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• pp.744-746
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• 2000

• Preventive Nutrition and Food Science
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• 제3권3호
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• pp.248-250
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• 1998

In this study, transferrin which is an iron-carrying glycoprotein in plasma was evaluted for its iron binding capacities(TIBC), iron solubilizing abilities, and enhancing effect of biological availbability of iron. Results of TIBC showed that 1 mg of transferrin could blind 1.28$\mu\textrm{g}$ of iron indicating that one molecule of transferrin can bind about 2 molecules of iron. Also, solubility of iorn (7.5$\mu\textrm{g}$ Fe/ml) was significantly incresed to 96.0% with addition of transferrin (5mg/ml) .When FeCl3(80$\mu\textrm{g}$ Fe/ml) was injected to iron-deficient rats by intestinal segment in situ technique, 18.4% of injected iron was absorbed wherease 48.49 and 48.76% of injected iron was absorbed with addition of 10 and 20 mg transferrin/ml , respectively.

• 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.

• 미생물학회지
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• 제39권1호
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• pp.51-55
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• 2003

환경친화적인 미생물인산비료를 개발하기 위하여 불용성 인산을 가용화 시킬 수 있는 세균을 콩의 근권 토양으로부터 분리하였다. 분리균주의 분류학적 위치를 검토한 결과, Pantoea agglomerans로 동정되었다. 불용성 인산인 $Ca_{3}(PO_{4})_{2}$)로부터 가용성 인산을 생성하기 위한 최적 배지 및 배양조건은 glucose 3%, $NH_{4}NO_{3}$ 0.1%, $MgSO_{4}\cdot\7H_{2}O$ 0.02%, $CaCl_{2}\cdot\2H_{2}O$, 0.06%,초기 pH 7.5, 배양온도 $30^{\circ}C$이었으며, 최적조건에서 배양 5 일 후,898 mg/L의 인산이 생성되었다. 불용성 인산 가용화 기작은 유기산 생성에 의한 배양액의 pH감소와 밀접한 관계가 있었다. 분리균주는 $CaHPO_{4}$, hydroxyapatite로부터 각각 698,912 mg/L의 가용성 인산을 생성하였으나 $FePO_{4}\cdot\4H_{2}O$, $AIPO_{4}$로부터는 각각 28,19 mg/L.의 가용성 인산을 생성하였다.