• 한국환경농학회지
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• 제18권3호
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• pp.287-291
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• 1999

Mycorrhizae가 형성된 식물에서 인광석이 인산급원으로 이용될 수 있는 지를 검토하기 위하여 온실 실험을 수행하였다. 멸균된 제주 화산회토에 인광석과 용성인비를 100및 200 mg P/kg 수준으로 처리하고 토마토를 재배하였는데 토마토는 mycorrhizae 접종구와 비접종구를 두고 3개월간 재배한 후 식물생육과 인을 비롯한 무기영양소 흡수를 조사하였다. 용성인비 처리구에 비하여 인광석 처리구에서 생육이 현저히 저해되었는데 이는 인광석처리에 따른 토양중의 유효인산 부족 때문일 것이다. 용성인비와 인광석 200 mg P/kg 처리구에스는 mycorrhizae균의 접종에 따라 건물량이 증가하였다. Mycorrhizae 형성율과 토양중의 포자밀도는 인광석 처리구에서 낮았다. 식물체중의 인 함량은 용성인비 처리구에서 높았으며, mycorrhizae 처리 효과는 없었다. N, K, Ca, Mg 등의 함량에서도 처리별로 차이는 없었다. 이상의 결과를 볼 때, 제주 화산회토양에서 $100{\sim}200\;mg\;P/kg$ 수준의 인광석 처리로는 mycorrhizae 형성 여부에 상관없이 적정 식물생육을 위한 인 공급이 될 수 없는 것으로 판단되었다.

• Journal of Microbiology and Biotechnology
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• 제27권6호
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• pp.1150-1156
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• 2017

Understanding phosphorus metabolism in photosynthetic organisms is important as it is closely associated with enhanced crop productivity and pollution management for natural ecosystems (e.g., algal blooming). Accordingly, we exploited highly time-resolved metabolic responses to different levels of phosphate deprivation in Chlamydomonas reinhardtii, a photosynthetic model organism. We conducted non-targeted primary metabolite profiling using gas-chromatography time-of-flight mass spectrometric analysis. Primarily, we systematically identified main contributors to degree-wise responses corresponding to the levels of phosphate deprivation. Additionally, we systematically characterized the metabolite sets specific to different phosphate conditions and their interactions with culture time. Among them were various types of fatty acids that were most dynamically modulated by the phosphate availability and culture time in addition to phosphorylated compounds.

• 한국작물학회지
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• 제19권
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• pp.59-68
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• 1975

야산개간지토양과 숙전토양을 대상으로 토양중 치환성 알미늄의 중화량에 해당하는 량의 석회를 시용한 조건과 석회를 시용하지않은 조건하에서 인산을 토양의 인산흡수계수의 2.5%, 5%, 7.5%에 상당하도록 다량시용 했을 때 용인과 중과석에 대한 대두의 반응을 조사하고, 석회시용이 2종류의 인산질비료의 비효에 어떻게 영양하는가를 구명하고자 pot에서 시험을 수행했던바 그 결과는 다음과 같다. 1. 인산다량시용 및 석회시용으로 야산개간지토양의 비옥도는 당년에 크게 증대되어 작물의 생육을 양호하게 하였고 숙전 이상의 수량을 얻을수 있었다. 2. 일반적으로 비효면에서 용인이 중과석보다 우수했으며 인산질비료로서 용인을 시용할 경우 중과석 보다 높은 수준의 양을 요구했다. 3. 식물체내의 가리함유율은 토양 및 식물체중의 √Ca+Mg의 크기와 통계적으로 높은 부의 상관관계를 보였다. 4. 개간지토양에서 용인단용구 및 석회와의 병용구는 파종후 40일경까지의 생육이 부진하였는데 이는 식물체의 인산 및 가리흡수율인 낮은데 기인했던 것 같다. 5. 용인단용 및 석회와의 병용효과를 높이기 위하여 앞으로 용인과 석회의 시용적기확인 및 석회, 약토, 가리의 균형시비를 감안한 가리시용량의 증대, 작물생육초기에 용인중의 인산용출속도문제등에 관한 연구가 있어야 할 것 같다.

• 한국환경농학회지
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• 제22권3호
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• pp.197-202
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• 2003

Phosphorus is one of the major plant growth limiting nutrients, despite being abundant in soils in both inorganic and organic forms. Phosphobioinoculants in the form of microorganisms can help in increasing the availability of accumulated phosphates for plant growth by solubilization. Penicillium oxalicum CBPSTsa, isolated from paddy rhizosphere, was studied for its phosphate solubilization. The influence of various carbon sources like glucose, sucrose, mannitol and sorbitol and nitrogen sources like arginine, sodium nitrate, potassium nitrate, ammonium chloride and ammonium sulphate were evaluated using liquid media with tricalcium phosphate (Ca-P), ferric phosphate (Fe-P) and aluminium phosphate (Al-P). Maximum soluble phosphate of 824 mg/L was found in the amendment of sucrose-sodium nitrate from 5 g/L of Ca-P. Mannitol, sorbitol, and ariginine were poor in phosphate solubilization. While sucrose was better carbon source in solubilization of Ca-P and Al-P, glucose fared better in solubilization of Fe-P. Though all the nitrogen sources enhanced P solubilization, nitrates were better than ammonium In the amendments of ammonium chloride and ammonium sulphate, higher uptake of available phosphates by the fungus was found, and this resulted in depletion of available P in Fe-P amendment Phosphate solubilization was accompanied by acidification of the media, and the highest pH decrease was observed in glucose amendment Among the nitrogen sources, ammonium chloride favored greater pH decrease.

• 한국해양바이오학회지
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• 제16권1호
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• pp.36-44
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• 2024

This study attempted to improve the growth of the freshwater microalgae, Parachlorella kessleri, through the sequential optimization of culture conditions. This attempt aimed to enhance the microalgae's ability to fixate atmospheric CO₂. Culture temperature and light intensity appropriate for microalgal growth were scanned using a high-throughput photobioreactor system. The supplied air flow rate varied from 0.05 to 0.3 vvm, and its effect on the growth rate of P. kessleri was determined. Next, sodium phosphate buffer was added to the culture medium (BG11) to enhance CO₂ fixation by increasing the availability of CO₂(HCO₃^-) in the culture medium. The results indicated that optimal culture temperature and light intensity were 20℃-25℃ and 300 μE/m²/s, respectively. Growth rates of P. kessleri under various air flow rates highly depended on the increase of the culture's flow rate and pH which determines CO₂ availability. Adding sodium phosphate buffer to BG11 to maintain a constant neutral pH (7.0) improved microalgal growth compared to control conditions (BG11 without sodium phosphate). These results indicate that the CO₂ fixation rate in the air could be enhanced via the sequential optimization of microalgal culture conditions.

• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.118-126
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• 2020

Silicon and phosphorus are elements that are beneficial for plant growth. Despite the abundant availability of silicate and phosphate in the Earth's crust, crop nutritional requirements for silicon and phosphorus are normally met through the application of fertilizer. However, fertilizers are one of the major causes of heavy metal pollution. In our study, we aimed to assess silicate and phosphate solubilization by the bacteria Enterobacter ludwigii GAK2, in the presence and absence of phosphate [Ca₃(PO₄)₂] or silicate (Mg₂O₈Si₃), to counteract cadmium stress in rice (Oryza sativa L). Our results showed that the GAK2-treated rice plants, grown in soil amended with phosphate [Ca₃(PO₄)₂] or silicate (Mg₂O₈Si₃), had significantly reduced cadmium content, and enhanced plant growth promoting characteristics including fresh shoot and root weight, plant height, and chlorophyll content. These plants showed significant downregulation of the cadmium transporter gene, OsHMA2, and upregulation of the silicon carrier gene, OsLsi1. Moreover, jasmonic acid levels were significantly reduced in the GAK2-inoculated plants, and this was further supported by the downregulation of the jasmonic acid related gene, OsJAZ1. These results indicate that Enterobacter ludwigii GAK2 can be used as a silicon and phosphorus bio-fertilizer, which solubilizes insoluble silicate and phosphate, and mitigates heavy metal toxicity in crops.

• Asian-Australasian Journal of Animal Sciences
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• 제27권8호
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• pp.1141-1149
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• 2014

The present study was conducted to investigate a supplemental effect of magnesium hydrogen phosphate (MHP, $MgHPO_4$) as an alternative phosphorus (P) source on growth and feed utilization of juvenile far eastern catfish (Silurus asotus) in comparison with three conventional P additives (monocalcium phosphate (MCP), dicalcium phosphate (DCP) and tricalcium phosphate [TCP]) as positive controls. A basal diet as a negative control was prepared without P supplementation and four supplemental P sources were added at the level of 2%. Five groups of 450 fish having mean body weight of 11.3 g following 24 h fasting after three week adaptation period were randomly distributed into each of 15 tanks (30 fish/tank). Fish were hand-fed to apparent satiety twice a day for 8 weeks. Fish fed MHP had weight gain (WG), protein efficiency ratio and specific growth rate comparable to those fed MCP. Fish fed MHP and MCP had feed efficiency (FE) significantly higher (p<0.05) than those fed DCP. Fish groups fed control and TCP showed the lower FE than the other groups which was significantly different (p<0.05) from those of fish fed the other diets. Survival rate was not significantly different (p>0.05) among treatments. Fish fed control had the lowest hematocrit, which was significantly different (p<0.05) from that of fish fed MHP. Fish fed MCP and MHP had plasma P higher (p<0.05) than fish fed the other diets. Relative efficiencies of MCP, DCP and TCP to MHP were found to be 100.5 and 101.3%, 92.0 and 91.6%, and 79.1 and 80.9% for WG and FE, respectively. P availability was determined to be 88.1%, 75.2%, 8.7%, and 90.9% for MCP, DCP, TCP, and MHP, respectively. Consequently, MHP recovered from wastewater stream showed that as an alternative P source its performance was comparative with MCP on growth and feed utilization of juvenile far eastern catfish.

• 한국환경농학회지
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• 제26권1호
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• pp.49-54
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• 2007

본 연구는 축분 퇴비시용에 따른 토양중 양분행동 양상을 구명하기 위하여 직경 30 cm 높이 1 m의 PVC pot에 화산회(구좌통) 토양과 비화산회(애월통) 토양을 충진하고 표토 20 cm 깊이로 계분 부숙퇴비, 돈분 부숙퇴비, 우분 부숙퇴비를 0, 50, 100, 150 ton/ha 해당량을 시용한 후 210일이 경과한 후 토양시료를 채취하여 풍건한 후 가축분 퇴비 처리에 따른 토양중 인산, 칼리 및 마그네슘의 유효화율을 조사한 결과는 다음과 같다. 가축분 퇴비의 시용은 통양중 유기물을 $23\sim111$, 질소 $80\sim450$ ton/ha 해당량을 시용하는 효과가 있었다. 가축분 퇴비의 시용에 따른 인산의 유효화율 변화는 $1.6\sim91.7%$로 가축분 종류에 따른 차이가 매우 컸는데 토양별로 비화산회 토양이 화산회토양에 비하여 월등히 큰 것을 알 수 있었다. 칼리의 유효화율 변화는 $22\sim94%$ 범위로 가축분의 종류 및 시용량에 따라 차이가 컸는데 가축분 종류에 따른 유효화율은 계분 부숙퇴비, 우분 부숙퇴비, 돈분 부속퇴비의 순으로 컸다. 칼슘의 유효화율은 화산회 토양은 $38\sim93%$ 비화산회 토양은 $9\sim90%$ 범위로 가축분 종류 및 토양의 특성에 따른 차이가 컸는데 가축분 종류별로 살펴보면 계분 부숙퇴비, 우분 부숙퇴비, 돈분 부숙퇴비의 순으로 컸다.

• 한국육종학회지
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• 제42권5호
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• pp.455-462
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• 2010

Purple acid phosphatase is important for phosphorus remobilization in plants, but its role in plant adaptation to low phosphorus availability is not known. The cDNA encoding O. sativa purple acid phosphatase (OsPAP1) has 1008 bp with an open reading frame of 335 amino acid residues. The amino acid sequence of OsPAP1 cDNA shows of 50-51% identity with other plant purple acid phosphatases. OsPAP1 was expressed in rice plants and in cell cultures in the absence of phosphate ($P_i$). The expression was organ-specific with the strongest expression in $P_i$-deprived roots. Functional expression of the OsPAP1 gene in the transgenic Arabidopsis line was confirmed by northern and western blot analysis. OsPAP1 overexpression lines had higher phosphatase activity than wild-type. Overexpression of OsPAP1 in Arabidopsis plants resulted in increased Pi accumulation under Pi sufficient condition. These results show that the OsPAP1 gene represents more efficient $P_i$ uptake and can be used to develop new transgenic dicotyledonous plants.

• 한국결정성장학회지
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• 제30권4호
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• pp.143-149
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• 2020

전복패각을 Ca원으로 이용하여 바이오 소재로 중요한 인산칼슘(calcium phosphates)들을 침전법을 통해 합성하였다. 전복패각에서 유래한 수산화칼슘(Ca(OH)₂)을 칼슘 공급원(전구체)으로 사용하였다. 수용액상에서 수산화칼슘과 인산(H₃PO₄)을 반응시켜 침전반응을 유도하여 인산칼슘화합물로의 합성을 유도하였다. 초기 전구체 Ca/P 비율을 1.50, 1.59 및 1.67로 조절하였으며 이 조성변화와 침전물에 대한 열처리가 분말 및 소결체의 물성에 미치는 영향에 대해 조사하였다. 초기 전구체 Ca/P 비율을 조절함으로써 소결체 상합성의 조절이 가능하였고, 1150℃에서 소결한 소결체에서(hydroxyapatite(HAp), β-tricalcium phosphate(β-TCP) 및 HAp와 β-TCP가 혼합된 2상 인산칼슘(BCP, HA/β-TCP))들이 합성되었다. 이러한 결과는 저비용, 고가용성을 가지는 경제적인 출발물질로부터 고부가가치 인산칼슘을 합성할 수 있는 가능성을 보여주었다.