• Korean Journal of Food Science and Technology
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• v.13 no.2
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• pp.121-126
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• 1981

An adenine-guanine doubless and $\beta$-alanine requiring mutant, D-1550-40, which had been derived from Brevibacterium ammoniagenes ATCC 6872, produced a copious amount of xanthosine-5'-monophosphate (XMP). The optimum concentration of adenine and guanine for maximal accumulation of XMP was about 75 ml/l and 100 ml/l for growth. Concentrations higher than 100 mg/l of adenine and guanine inhibited cell growth and XMP accumulation strongly. The inhibition, however, could be recovered by adding $100{\mu}g$ of biotin per liter or 0.3% of casamino acids to the culture solution. High concentrations of phosphate and magnesium salts (1.0 to 1.5%(w/v) in media) were found to be indispensable for XMP accumulation, and the presence of manganese in the culture medium stimulated both growth of cells and accumulation of XMP leaving 5'-inosinic acid unaffected. The maximal accumulation of XMP reached to 60.5 mg/l after 4 days of fermentation which had been started with a medium containing 100 mg of adenine-guanine, 5 mg of $MnSO_4{\cdot}H_2O$ and $100{\mu}g$ of biotin per liter. The specific XMP synthesis(mg of XMP/mg of cells) was increased with the increase of the cell growth rate.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.321-325
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• 2004

국내 충적층의 철, 망간 문제는 지속적으로 지적되어오던 수질항목이다. 충적층 지하수 내 철과 망간의 용존 특성을 확인하고자 강변여과수 부지에서 지하수의 수리지화학적 특성을 조사하였다. Fe와 Mn에 의해 오염된 관정은 D-2와 DS-3로 모두 3월에 채취한 시료이며 NO$_3$-N는 모두 0 m/L 이다. NO$_3$-N에 대해 다른 관정은 2 mg/L NO$_3$-N를 넘고 있으며, DS-8와 DS-3에서 11.30과 20.2 mg/L NO$_3$-N의 값으로 먹는물 수질기준을 초과하고 있다. Mn에 대해 오염된 관정은 SJ-3이다. 10월에 채취한 시료에서 DS-2+l8 m에서 채취한 시료가 1.16 mg/L인 것을 제외하고 대부분의 시료가 2 mg/L를 초과하고 있고, DS-6+l3 m과 SJ-3＋10 m에서 채취한 시료가 각각 10.71과 10.31 mg/L NO$_3$-N로 먹는물 수질기준을 초과하고 있다. DO 검층 자료와 NO$_3$-N 농도를 이용하여 Fe와 Mn이 먹는물 수질 기준을 초과하는 D-2와 DS-2 관정의 지하수 체의 혐기성 상태임을 확인하였다. 강변여과수 지역은 전반적으로 NO$_3$-N에 대해 인위적인 오염이 발생하고 있으며, 혐기성 상태 구간이 존재함에 따라서 Fe와 Mn이 먹는물 수질 기준을 초과하여 용존 상태로 존재한다.

• Journal of the Korean Ceramic Society
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• v.38 no.2
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• pp.173-178
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• 2001

본 연구에서는 PDP용 녹색 형광체의 대안인 $Ba_{1.3}$A $l_{12}$ $O_{19}$:$Mn^{2+}$ 분말을 초음파 분무 열분해법으로 합성하였으며 활성제인 $Mn^{2+}$의 첨가량과 모체를 구성하는 바륨 및 알루미늄의 전구체 물질들의 조합을 변화시킴으로써 형광체 분말의 형태 및 발광특성을 조절하였다. 최적의 발광 휘도를 나타내는 $Mn^{2+}$의 농도는 0.25몰을 첨가하였을 때이며 녹색 발광 영역인 517nm에서 최대 발광 효율을 나타내었다. 바륨의 전구체 물질로는 초산염, 질산염, 염화물 및 수산화물을 사용하였으며 알루미늄 전구체 물질로는 질산염 및 염화물을 사용하였다. 전구체는 합성된 분말의 형상에 영향을 미치는데 구형을 유지하거나 혹은 뭉치거나 구형이 깨지는 등 전구체 조합에 따라 얻어지는 분말의 형태가 달라졌다. 합성된 형광체 분말들은 일반적인 고상 반응의 온도보다 낮은 열처리 온도인 140$0^{\circ}C$, 5시간 유지에서는 좋은 VUV 발광 특성을 가졌다. 또한 전구체의 조합은 형광체 발광 효율에도 영향을 미치는데 바륨과 알루미늄은 염화물을, 망간은 질산염을 사용하였을 때 가장 좋은 발광 휘도를 나타내었다.다.다.다.

• KSBB Journal
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• v.17 no.1
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• pp.14-19
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• 2002

The objective of this study is to investigate optimum condition for lignin peroxidase production by white rot fungi Phanerochaete chysosporium IFO 31249 immobilized in a rotating bioreactor. The maximum lignin peroxidase activity of batch culture in rotating bioreactor was 300 U/L. The optimum rotating speed and packing ratio of support for lignin peroxidase production in a rotating bioreactor were 1 rpm and 20%, respectively. The optimum concentration of $MnSO_4$$\cdot$$H_2O$ for manganese-dependent peroxidase production in a rotating bioreactor was 50 ppm. The sufficient supply of oxygen was the most important factor to achieve maximum lignin peroxidase production. It was possible to produce lignin peroxidase (LiP) and manganese-dependent peroxidase (MnP) for at least 3 times successive repeated-batch cultures, respectively.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.33-34
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• 2004

Effect of dietary 2.0 % brown seaweed(Undaria pinnatifida) with bean extract on anti-oxidant system and TNF-$\alpha$ levels were evaluated in blood of 2 week-old broiler chicks activated innate immune response. Dietary brown seaweed and activation of innate immune response decreased MnSOD activities. while activation of innate immune reponse only increased CuZnSOD activities in erythrocyte cytosol. Activation of innate immune response lowered plasma SOD activity in birds fed seaweed with bean extract, increased peroxide levels, and decreased peroxidase activity in plasma. Brown seaweed with bean extract reduced TNF-$\alpha$ levels and increased ovotransferrins concentrations in plasma. The result indicated that dietary 2.0 % brown seaweed with bean extract affect innate immune response changing anti-oxidant system and TNF-$\alpha$ levels in broiler chicks.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1129-1133
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• 2010

본 연구에서는 수질오염총량제와 정책제안의 원활하고 합리적인 추진을 위해 토지피복분류체계의 대분류중 초지에 해당하고 중분류 중 골프장에 해당하는 지점을 선정하여 강우에 의해 발생하는 비점오염물질의 유출특성을 분석하였다. 연구기간 동안 총 27번의 강우사상으로 인해 발생하는 강우유출수에 대하여 유량과 수질농도를 측정하였다. 유량측정은 웨어를 통한 수위를 측정하여 유량으로 환산하였고, 수질항목은 $BOD_5$, $COD_{Mn}$, DOC, SS, T-N, T-P, $NH_3$-N, $NO_3$-N, $PO_4$-P 등 9개 항목을 분석하였다. 분석된 결과를 이용하여 골프장에서 발생하는 비점오염원의 초기세척효과 발생여부를 판단하기 위하여 누적오염부하량/누적유출량 그래프를 도식화하였다. 연구기간동안 발생한 5~82 mm의 강우로 인해 6.6~2,082 $m^3$의 유출이 발생하였다. 발생된 유출수의 농도는 $BOD_5$ 1.8~11.3 mg/L, $COD_{Mn}$ 19.2~51.4 mg/L, DOC 11.0~31.0 mg/L, SS 2.2~57.3 mg/L, T-N 1.545~16.098, T-P 0.230~4.528 mg/L, $NH_3$-N 0.076~5.285 mg/L, $NO_3$-N 0.122~2.905 mg/L, $PO_4$-P 0.005~2.631 mg/L로 나타났다. 초기유출수의 세척효과는 27번의 강우사상동안 SS 항목의 경우 17번, $NO_3$-N 11번, $NH_3$-N 4번 등이 발생하였다. 초기세척효과가 발생한 강우사상은 초기의 오염원 농도가 중 후반 농도보다 농도가 높음을 의미하므로, 골프장에서 발생하는 강우유출수는 초기에 발생하는 오염원에 초점을 두고 처리방안을 모색해야 할 것으로 판단된다. 또한 SS와 질소계열의 농도가 높은 것은 골프장의 잔디관리를 위한 농약이나 제초제 등의 사용과 토양유실이 원인인 것으로 판단되며, 이를 저감하기 위한 적절한 사용방안과 저감대책이 필요할 것으로 판단된다.

• KSBB Journal
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• v.5 no.2
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• pp.119-124
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• 1990

Phospholipase D catalyzes the phosphatidohydrolysis and transphosphatidylation of phospholipid in the biological systems. In this study we were partially purified phospholipase D from Chinese cabbage and the characterization of the enzyme was carried out in a multistirring batch system bioreactor. The enzyme showed optimum activity at pH ,5.6, highest activity at 37$^{\circ}C$ and Ca2+ is important for the enzyme activity. Optimum concentrations of Ca2+ for phosphatidohydrolysis was 20 mM and for transphosphatidylation was 40 mM, respectively. Some organic solvents such as diethylether, isopropylether and butylacetate were activated the enzyme activity. On the other hand, EDTA, Ba2+, Mn2+ and Zn2+ showed inhibitory effect on the enzyme activity. The base acceptors in transphosphatidylation by the Chinese cabbage phospholipase D were tested. Various poly-and monohydroxy alcohols were found to be active.

• Journal of the Korean earth science society
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• v.27 no.3
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• pp.313-327
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• 2006

This study investigated the geochernical characteristics of Mn scale formed in groundwater wells at the Damyang area. The composition of Mn scale consists mainly of MnO and $SiO_2$. The content of Mn ranges from56.61wt.% to 68.69wt.%, and $SiO_2$ content ranges from 1.56wt.% to 10.45wt.%. The contents of Mo and Ba in Mn scale increased with increased depth; whereas, the content of Zn and Pb decreased with increased depth. Birnessite, quartz and feldspars were identified in Mn scales using x-ray powder diffraction studies. The IR absorption bands for Mn scales show major absorption band due to OH stretching, adsorbed molecular water, and birnessite stretching, respectively. In the SEM and EDS analysis, the Mn scale consists of botryoidal, spherical, spherulite, and empty straw structure. Those structure may be precipitated simply due to oversaturation with concentrated Mn content or may be formed through biogenic precipitation by Lepthothrix discophora. Under microanalysis using EDS on those structure surface of Mn scales, the Mn atomic percent range from 28 to 44, and such elements revealed the presence of Si, K, Na, Ca, Cl, Cu, Zn, and Ba.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.348-351
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• 2012

The effect of the addition of Cu on the catalytic activity of the $Mn/CeO_2-ZrO_2$ catalyst for the low-temperature SCR reaction of NO was investigated. Three different amounts of Cu, 5, 10, and 15 wt%, were impregnated on the $Mn/CeO_2-ZrO_2$ catalyst. The characteristics of the synthesized catalysts were examined by BET, XRD, XPS, and $H_2-TPR$ analyses. The de-NOx efficiency of the Cu-added catalysts increased with the amount of Cu. When 15 wt% Cu was impregnated, the deNOx efficiency was the highest, reaching as high as 99%. The increased deNOx efficiency is attributed to the enhanced reducing power stemming from the interaction between Mn and Cu on the catalyst surface.

• Microbiology and Biotechnology Letters
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• v.10 no.1
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• pp.1-7
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• 1982

A Rhizopus sp. was selected for its strong cellulolytic activity among various strains of molds found in rotting ginseng roots. Studies were made on some properties of the cellyloiytic enzyme produced by the strain. The results obtained were summarized as follows: The optimum pH of the enzyme was 4.5 and the range of its stability to the pH was 3.0 to 7.0. The optimum temperature was 5$0^{\circ}C$, while the enzyme was instantly inactivated above 6$0^{\circ}C$. Mn$^{＋＋}$ and Co$^{＋＋}$ ions increased enzyme activity and the metal ions were found to increased the ther-mostability of the enzyme. This enzyme was inhibited by sodium dodecyl sulfate and 2,4-dinitrophenol. This enzyme had a strong cellulolytic enzyme activity on various native cellulose given a sufficient reaction time. The addition of 0.5% saponin solution into reaction mixture increased the enzyme activity.