• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.334-337
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• 2003

This study was carried out to investigate the effect of soil properties, such as soil organic matter(SOM) content and water content on die-off and regrowth of indigenous microbes due to in-situ ozonation. Four different soils were collected and the soil samples applied to different ozonation time(0-360 min) were incubated during 4 weeks. Population of the indigenous microbes was monitored during incubation period. The number of indigenous microbes in all samples dramatically decreased (more than 90%) within 30 minutes of ozone injection. With increased ozonation time by 360 minutes, the number of the indigenous microbes decreased by 99.99% in all samples. Die-off of the indigenous microbes due to ozone treatment was inversely proportional to SOM and water content. Especially, sample 3 and Sample 4 containing relatively high SOM content and water content showed high regrowth rate, and this resulted from the increase of water soluble and biodegradable organic fraction in soil water after ozone treatment. Soil sample ozonated for 360 minutes showed minor increase in microbial population during 4 weeks of incubation period.

• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.101-105
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• 2002

Fine root decomposition and nutrient release patterns were examined using in situ buried fine root (< 2mm in diameter) bags inserted vertically into the mineral soil to a depth of the top 15 cm in a sawtooth oak (Quercus acutissima) and a Korean pine (Pinus korainesis) stands in the Jungbu Forest Experiment Station, Kyonggi-do, Korea. The pine roots compared with the oak roots showed rapid mass loss in early stages of decomposition, but decomposed similarly after 12 months of incubation. Decomposition rates of fine roots were about 33%/yr for the oak roots and 37%/yr for the pine roots. Nutrients except for calcium and phosphorus showed similar concentrations between the oak and the pine roots during the study period. However, calcium concentration was significantly higher in the oak than in the pine roots. Nutrient concentrations in both stands except for nitrogen decreased during the study period. In addition, potassium compared with other nutrients was the most mobile ion and about 70% of initial amount was released during the first 3 months of incubation. The results indicate that tree species influence mass loss and nutrient dynamics of fine roots on similar site conditions.

• Corrosion Science and Technology
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• 제7권3호
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• pp.168-172
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• 2008

A new type of electrochemical random signal (electrochemical noise) analysis technique was applied to localized corrosion of anodic oxide film formed 1100 aluminum alloy in $0.5kmol/m^3$ $H_3BO_4/0.05kmol/m^3$ $Na_2B_4O_7$ with $0.01kmol/m^3$ NaCl. The effect of anodic oxide film structure, barrier type, porous type, and composite type on galvanic corrosion resistance was also examined. Before localized corrosion started, incubation period for pitting corrosion, both current and potential slightly change as initial value with time. The incubation period of porous type anodic oxide specimens are longer than that of barrier type anodic oxide specimens. While pitting corrosion, the current and potential were changed with fluctuations and the potential and the current fluctuations show a good correlation. The records of the current and potential were processed by calculating the power spectrum density (PSD) by the Fast Fourier Transform (FFT) method. The potential and current PSD decrease with increasing frequency, and the slopes are steeper than or equal to minus one (-1). This technique allows observation of electrochemical impedance changes during localized corrosion.

• Archives of Pharmacal Research
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• 제25권1호
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• pp.80-85
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• 2002

The incubation of porcine renal proximal tubules (PTs) resulted in the release of the Glycosylphosphatidylinositol (GPI)-anchored renal dipeptidase (RDPase, EC 3. 4. 13. 19) from the membrane after a lag period of approximately 6 hours. This spontaneous release of RDPase from the membrane was inhibited by antibiotics. When the incubation supernatant was added back to fresh PTs, both the antibiotic inhibition of RDPase release and the lag period disappeared. The released RDPase reacted with an anti-cross reacting determinant antibody indicating the presence of the Ins (1, 2-cyc)P. These results suggest that bacteria in the PTs, when incubated, grow find Secrete a phosphatidylinmsitol-specific phospholipase C (PIPLC). This enzyme then hydrolyses the GPI-anchored RDPase and is transferable. RDPase was purified following its release from the membrane by this simple and inexpensive method which may also be applied to other GPI-anchored proteins.

• The Korean Journal of Ecology
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• 제25권4호
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• pp.235-239
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• 2002

Fine root decomposition and nutrient release patterns were examined using in situ buried fine root (＜ 2mm in diameter) bags inserted vertically into the mineral soil to a depth of the top 15 cm in a sawtooth oak (Quercus acutissima) and a Korean pine (Pinus korainesis) stands in the Jungbu Forest Experiment Station, Kyonggi-do, Korea. The pine roots compared with the oak roots showed rapid mass loss in early stages of decomposition, but decomposed similarly after 12 months of incubation. Decomposition rates of fine roots were about 33%/yr for the oak roots and 37$\%$/yr for the pine roots. Nutrients except for calcium and phosphorus showed similar concentrations between the oak and the pine roots during the study period. However, calcium concentration was significantly higher in the oak than in the pine roots. Nutrient concentrations in both stands except for nitrogen decreased during the study period. In addition, potassium compared with other nutrients was the most mobile ion and about 70$\%$ of initial amount was released during the first 3 months of incubation. The results indicate that tree species influence mass loss and nutrient dynamics of fine roots on similar site conditions.

• Mycobiology
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• 제51권3호
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• pp.157-163
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• 2023

Cordyceps fumosorosea is an important species in the genus of Cordyceps, containing a variety of bioactive compounds, including fumosorinone (FU). This study was a ground-breaking assessment of FU levels in liquid and solid cultures. The present study focused on the impacts of solid-state fermentation (SSF) using solid substrates (wheat, oat, and rice), as well as the effects of fermentation parameters (pH, temperature, and incubation period), on the generation of FU. All the fermentation parameters had significant effects on the synthesis of FU. In a study of 25 ℃, 5.5 pH, and 21 days of incubation period combinations calculated -to give maximal FU production, it was found that the optimal values were 25 ℃, 5.5 pH, and 21 days, respectively. In a solid substrate medium culture, FU could be produced from SSF. At 30 days, a medium composed of rice yielded the most FU (798.50 mg/L), followed by a medium composed of wheat and oats (640.50 and 450.50 mg/L), respectively. An efficient method for increasing FU production on a large scale could be found in this approach. The results of this study might have multiple applications in different industrial fermentation processes.

• 한국식품조리과학회지
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• 제25권2호
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• pp.170-179
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• 2009

This study examined effects on shelf-life extension and prevention of starch retrogradation in rye-wheat mixed bread (RWMB) samples prepared with substitutions of 20, 40, 60, and 80% rye sourdough (RSD) as well as a control made with the addition of naturally fermented raisin extract. These effects were investigated using mold growth, water activity, and textural characteristics during a storage period of 8 days at $20^{\circ}C$. The activities of the rye sourdough were examined in terms of pH, total titratable acidity, general bacteria, lactic acid bacteria, and yeast counts. As the incubation time of the sour dough increased, pH decreased, while total titratable acidity increased. General bacteria, lactic acid bacteria, and yeast counts increased with increasing incubation time. Mold grew on the external surface of the control group after 6 days and on the surface of the RSD bread samples after 8 days, respectively. With regard to water activity, the control group had increasing activity as the storage period increased. In addition, the 20, 40, 60, and 80% RSD samples had increasing water activities until the 4th day however, these strongly decreased by the 6th day. In terms of textural characteristics, as the storage period increased, hardness increased, while springiness, cohesiveness, and resilience decreased. There were no significant differences in gumminess among the samples. The control, 20, 40, and 60% RSD samples had decreases in chewiness with increasing storage time, however, the 40% RSD sample did not differ significantly during the storage period. Finally, water activity was negatively correlated with hardness (p<0.05). In conclusion, the results indicate that substituting rye sourdough in rye-wheat mixed bread has a prolongation effect on shelf-life, but no effect on the prevention of starch retrogradation.

• Parasites, Hosts and Diseases
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• 제30권3호
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• pp.169-176
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• 1992

여섯 계통의 근교계 마우스떠에 상흡충의 기생기간과 경시적 산란력을 근거로 하여 숙주 기생충 관계의 계통별 차이를 구명하기 위해 마우스찰 20개의 간흡충 피낭유충을 경구적으로 감염시켰다. 감염 후 간흡충의 충란이 처음 검출될 때까지의 기간은 DDY 마우스에서 평균 21.2일로 가장 짧았고, GPC 21.48, BALB/c 및 DS 23.2 5, ICR 및 nude 23.4일의 순이 었다. 총산란기간 역시 DDY 마우스에서 164일로 가장 길었으며, GPC 132R, BALB/c 97일, nude 37일, DS 32일 및 ICR 28일의 순이었다. DDY 및 GPC 마우스에서는 간흡충의 산란수가 비교적 높고 안정적이었으나 나머지 4계통의 마우스에서는 관찰기간 동안 불규칙하였다. 이상의 성적으로 미루어 보아 마우스의 계통에 따라 간흡충의 숙주 기생충 관계의 차리를 확인하였고 DDY 마우스가 6계통중 가장 호적숙주임을 알았다.

• 한국환경과학회지
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• 제28권4호
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• pp.435-439
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• 2019

This study was carried out to investigate the changes in the amount of 20 free amino acids in PDB (Potato Dextrose Broth) medium during the incubation period while cultivating Lentinula edodes. The total incubation period was 90 days, and the total amount of free amino acids was confirmed every 45 days. Among the 18 kinds of amino acids whose increase and decrease patterns were confirmed, 10 amino acids were increased compared to that in the control, among which cysteine increased from its initial value of $9,889{\pm}3{\mu}g/L$ to $12,909{\pm}2{\mu}g/L$ at 45 days and $29,256{\pm}4{\mu}g/L$ at 90 days. Six amino acids with decreased expression patterns were identified. Arginine decreased to $83,751{\pm}2{\mu}g/L$ after 45 days from its initial value of $161,787{\pm}1{\mu}g/L$ and to $79,055{\pm}7{\mu}g/L$ at 90 days.

• 한국식품과학회지
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• 제15권4호
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• pp.370-378
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• 1983

Aspergillus oryzae에 의한 개량(改良)메주의 숙성과정(熟成過程)에 있어서 단백질 및 아미노산 조성(組成)의 변화(變化)를 체계적(體系的)으로 규명(糾明)하기 위하여 disc gel electrophoresis 및 아미노산 분석기기(分析機器)에 의한 실험결과(實驗結果)는 다음과 같다. 1. 농도(濃度)가 다른 $Na_{2}SO_{4},\;MgSO_{4},\;Na_{2}CO_{3},\;NaCl$ 및 $Na_{2}SO_{4}$의 염(鹽)을 이용하여 대두의 염용해성(廉溶解性) 단백질을 분리(分離)한 결과(結果) 0.4M $Na_{2}SO_{4}$용액(溶液)에서 그 수득율(收得率)(30%)이 가장 높았다. 2. 대두 단백질을 분별정량(分別定量)한 결과(結果) 그 함유량(含有量)이 가장 많은 것은 albumine 46.0% 였으며 globulin 33.9%, glutelin 19.5%, prolamin 2.4%순이였으며 메주의 숙성과정(熟成過程) 중(中)에 있어서 albumin과 prolamin 은 차차 증가(增加)하였으나 glutelin은 감소(減少)하였고 globulin은 큰 변화(變化)가 없었다. 3. Sephadex G-200으로 albumin을 분획(分劃)한 결과(結果) 대두에서는 6개, 숙성(熟成) 0일에서는 3개, 6일 째는 8개로 증가(增加)하였다. 4. 대두 및 메주의 발효과정(醱酵過程)에 있어서 아미노산은 다같이 17종류(種類)로 glutamic acid 및 aspartic acid가 제일 많았으며 삶은 콩이 메주에 비(比)하여 albumin의 아미노산조성(組成) 가운데 arginine, aspartic acid, glutamic acid 및 glycine의 함량(含量)이 많았다. 5. Sephadex G-200으로 albumin을 분획(分劃)한 결과 대두및 메주에서 주(主)된 단백질의 조성(組成)아미노산은 17 종류(種類)로 그 함량(含量)은 aspartic acid 및 glutamic acid가 제일 많았으며, 메주의 발효과정(醱酵過程)에 있어서 albumin의 주(主)된 단백질의 amino acid 조성변화(組成變化)는 lysine, histidine, phenylalanine, threonine, serine, alanine, isoleucine, leucine, phenylalanine 및 $NH_3$가 차차 증가(增加)하였으며 이 밖의 다른 아미노산은 감소(減少)하였다. 6. 전기영동(電氣泳動)의 pattern에서 대두 단백질의 band 수(數)는 13개로 나타났으며 메주 숙성과정(熟成過程)에 있어서는 처음 3개에서 6일째에는 10개의 band로 차차 증가(增加)하였다. 메주의 발효과정(醱酵過程) 중(中)에 있어서 albumin의 주(主)된 단백질의 분구량(分句量)은 대두에서 175,000이었고 0 일때 135,000에서 6 일째는 36,000으로 감소(減少)하였다.