• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1747-1756
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• 2013

The aim of this paper was to study the effect of spent medium recycle on Spodoptera exigua Se301 cell line proliferation, metabolism, and baculovirus production when grown in batch suspension cultures in Ex-Cell 420 serum-free medium. The results showed that the recycle of 20% of spent medium from a culture in mid-exponential growth phase improved growth relative to a control culture grown in fresh medium. Although both glucose and glutamine were still present at the end of the growth phase, glutamate was always completely exhausted. The pattern of the specific glucose and lactate consumption and production rates, as well as the specific glutamine and glutamate consumption rates, suggests a metabolic shift at spent medium recycle values of over 60%, with a decrease in the efficiency of glucose utilization and an increase in glutamate consumption to fuel energy metabolism. Baculovirus infection provoked a change in the metabolic pattern of Se301 cells, although a beneficial effect of spent medium recycle was also observed. Both growth rate and maximum viable cell density decreased relative to uninfected cultures. The efficiency of glucose utilization was dramatically reduced in those cultures containing the lowest percentages of spent medium, whereas glutamine and glutamate consumption was modulated, thereby suggesting that infected cells were devoted to virus replication, retaining their ability to incorporate the nutrients required to support viral replication. Recycle of 20% of spent medium increased baculovirus production by around 90%, thus showing the link between cell growth and baculovirus production.

• 한국버섯학회지
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• 제9권1호
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• pp.44-47
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• 2011

느타리버섯 병 재배용으로 널리 사용되고 있는 미송톱밥, 비트펄프, 면실박(50:30:20) 혼합배지에 춘추느타리 2호를 재배한 배지를 풀버섯 재배 배지인 면실피펠릿, 밀기울, 탄산칼슘분말(90:9:1)배지에 혼합하여 상자재배시험을 통한 배양 및 생육특성을 비교분석한 결과, 느타리버섯 수확 후 배지의 첨가량이 많을수록 배지의 pH는 낮아지는 경향이었고, 총질소 함량이 높아 C/N율이 낮았다. 또한 미생물 밀도는 느타리버섯 수확 후 배지 첨가량 50%일 때 가장 높았으며 오염은 첨가량 0, 25, 50%가 10~13%로 비교적 낮은 오염율을 보였다. 균사배양기간 7일, 초발이 소요일수는 11~14일, 수확기간은 3~5일로 처리 간의 차이가 적어 총 재배기간도 큰 차이를 보이지 않았다. 수량은 기본배지인 면실피 펠릿 발효 배지(대조구, 356g/상자)보다 수확 후 배지 첨가량 50%+기본배지(면실피 펠릿 발효 배지)처리구가 같은 수량을 나타냈으며, 또한 수확 개체수 및 개체중도 대조구와 동등하여 수확 후 배지를 이용한 배지재료 절감효과가 인정되었다.

• International Journal of Oral Biology
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• 제39권1호
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• pp.35-40
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• 2014

Halitosis is caused by consumption of certain foods or drinks and production of volatile sulfur compounds (VSCs) by periodontopathogens. VSCs-related halitosis is not easily removed using mechanical or chemical therapies such as dental floss, plaque control and mouth rinse. Lactobacillus are known to be probiotics and stimulate immune systems of human. Furthermore, L. casei ATCC 334 and L. rhamnosus GG have an effect on protection of dental caries in vitro studies. The aim of this study was to investigate effect of Lactobacillus on halitosis by Fusobacterium nucleatum- and Porphyromonas gingivalis-producing VSCs and to analyze inhibitory mechanism. The periodontopathogens were cultivated in the presence or the absence Lactobacillus, and the level of VSCs was measured by gas chromatograph. For analysis of inhibitory mechanisms, the susceptibility assay of the spent culture medium of Lactobacillus against F. nucleatum and P. gingivalis was investigated. Also, the spent culture medium of Lactobacillus and periodontopathogens were mixed, and the emission of VSCs from the spent culture medium was measured by gas chromatograph. L. casei and L. rhamnosus significantly reduced production of VSCs. L. casei and L. rhamnosus exhibited strong antibacterial activity against F. nucleatum and P. gingivalis. The spent culture medium of L. casei inhibited to emit gaseous hydrogen sulfide, methyl mercaptan and dimethyl sulfide from the spent culture medium of periodontopathogens. However, the spent medium of L. rhamnosus repressed only dimethyl sulfide. L. casei ATCC 334 may improve halitosis by growth inhibition of periodontopathogens and reduction of VSCs emission.

• 한국축산시설환경학회지
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• 제6권3호
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• pp.201-209
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• 2000

수평아리 사체를 이용한 효모의 최적 배양 조건과 효모배양물이 육계의 성장에 미치는 영향을 조사하였다. 수평아리 추출물의 단백질 농도는 72시간 동안 추출되었을 때 가장 높았으며, 수평아리 사체에서 추출물을 얻기 위한 물의 첨가 비율은 수평아리 사체의 무게에 1.5배(v/w ratio)가 적당하였다. 수평아리 사체의 추출물에서 지방은 효모의 성장에 영향을 미치지 못하였다. 수평아리 사체의 추출물과 4% sugarcane molasses로 구성된 SCELP2 배지는 1% yeast extract, 2% bacto pepton 그리고 2% glucose로 구성된 YEPD 배지보다 효모수가 26% 더 증가하였다. 또한 SCELP2 배지에 4% 폐이스트를 첨가한 SBYW2 배지는 SCELP2 배지보다 효모수가 8% 증가하였다. SBYW2 배지에서 배양된 효모배양물을 5주 동안 육계에 급여한 결과 종체량은 4% 첨가구가 대조구보다 9% 증가하였다. 따라서 본 연구 결과 부화부산물로 발생되는 수평아리 사체는 사료용 효모배양물을 생산하기 위한 효모배양 배지의 질소원으로서 이용될 수 있음을 의미한다.

• 한국유기농업학회지
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• 제31권4호
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• pp.427-439
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• 2023

The silverleaf whitefly, Bemisia tabaci, is a major pest distributing worldwide damaging over 900 host plant species, and is highly resistant to chemical pesti- cides. Due to the high pesticide resistance of whitefly, there is a need for alternatives to chemical control. Entomopathogenic fungi are candidates for biological pesticide that can overcome the resistance problem of chemical pesticide. Therefore, in this study, we tested pathogenicity of the entomopathogenic fungi to select high insec- ticidal activity against whitefly. As a result, IPBL-C (Cordyceps fumosorosea) and IPBL-F (Metarhizium pinghaense) isolates showed high insecticidal activity against whitefly. Additionally, as a result of culturing the selected isolates on spent coffee grounds medium, the conidia of IPBL-F produced on coffee grounds medium showed five times higher heat stability after heat treatment at 45℃ for one hour than conidia produced on PDA medium.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.564-570
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• 2005

In the present study, the protective effects of Bcl-2 over-expression in a suspension culture (without any adaptation) and spent medium (low nutrient and high toxic metabolite conditions) were investigated. In the suspension culture without prior adaptation, the viability of the control cell line fall to 0% by day 7, whereas the Bcl-2 cell line had a viability of 65%. The difference in the viability and viable cell density between the Bcl-2 and control cell lines was more apparent in the suspension culture than the static culture, and became even more apparent on day 6. Fluorescence microscopic counting revealed that the major mechanism of cell death in the control cell line in both the static and suspension cultures was apoptosis. For the Bcl-2 cell lines, necrosis was the major mode of cell death in the static culture, but apoptosis became equally important in the suspension culture. When the NS0 6A1 cell line was cultured in spent medium taken from a 14 day batch culture, the control cell line almost completely lost its viability by day 5, whereas, the Bcl-2 still had a viability of 73%. The viable cell density and viability of the Bcl-2 cell line cultivated in fresh medium were 2.2 and 2.7 fold higher, respectively, than those of the control cultures. However, the viable cell density and viability of the Bcl-2 cultivated in the spent medium were 8.7 and 7.8 fold higher, respectively, than those of the control cultures. Most of the dead cells in the control cell line were apoptotic; whereas, the major cell death mechanisms in the Bcl-2 cell line were necrotic.

• 센서학회지
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• 제23권4호
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• pp.245-250
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• 2014

When the charged particle travels in transparent medium with a velocity greater than that of light in the same medium, the electromagnetic field close to the particle polarizes the medium along its path, and then the electrons in the atoms follow the waveform of the pulse which is called as Cerenkov light or radiation. This type of radiation can be easily observed in a spent fuel storage pit. In optical fibers, the Cerenkov light also can be generated due to their dielectric components. Accordingly, the radiation-induced light signals can be obtained using optical fibers without any scintillating material. In this study, to measure the intensities of Cerenkov radiation induced by gamma-rays, we have fabricated the fiber-optic Cerenkov radiation sensor system using silica optical fibers, plastic optical fibers, multi-anode photomultiplier tubes, simulated spent fuel assembly and a scanning system. To characterize the Cerenkov radiation generated in optical fibers, the intensities of Cerenkov radiation generated in the silica and plastic optical fibers were measured. Also, we measured the longitudinal distribution of gamma rays emitted from the Ir-192 isotope by using the fiber-optic Cerenkov radiation sensor system and simulated spent fuel assembly.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.413-416
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• 2000

The spent fuel skeleton is processed in the cutting processing after compacting. If the cutting length is processed in the same interval length. The spent fuel skeleton is stayed on the connection of bottom nozzle and guide tube. In the case, because the compressive stress is loaded along the length, the guide tube is generated the buckling stress and the deforming. But the deformed guide tube interrupted the guide tube inserted through compressive room. therefore, it is experimented for the optimum buckling stress and the preventing of guide deformed. This paper is predicted the all over buckling stress of the spent fuel skeleton by using experiment. The guide of Spent fuel skeleton have buckling characteristics of the medium column. The experiment and analysis is conducted by the comparing among the equation of Euler, Johnson and Engresser. The fittest one of method is Engresser equation.

• Asian-Australasian Journal of Animal Sciences
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• 제24권11호
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• pp.1560-1568
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• 2011

This study was conducted to evaluate the yield, nutrient characteristics, ruminal solubility, degradability and disappearance of spent mushroom (Agaricus bisporus) substrates for ruminants. The annual yield of spent Agaricus bisporus substrates was measured to be about 210,000 tons (M/T) in South Korea. The surface soil-removed spent substrates had nutritional characteristics of high crude ash (375 g/kg) and Ca (32 g/kg), medium protein (134 g/kg CP), and high fiber (384 g/kg NDF on a DM basis). Compared with initial mushroom substrates, spent mushroom substrates had twice higher (p<0.0001) CP content and 22.0% lower (p<0.0001) NDF content on an organic matter basis. Compared with raw rice straw, spent rice straw had much higher (p<0.05) predicted ruminal degradabilities and disappearances of DM and CP and a little lower (p<0.05) predicted degradability and disappearance of NDF. In conclusion, the general feed-nutritional value of spent mushroom (Agaricus bisporus) substrates appeared to improve after cultivation of mushrooms.

• Journal of Animal Science and Technology
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• 제54권6호
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• pp.435-442
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• 2012

This study was conducted to isolate and identify the lactic acid bacteria (LAB) from spent mushroom substrates (SMS) for the effective anaerobic fermentation to utilize SMS as an animal feed and to determine the optimal medium conditions for their growth. At first, a total of 23 strains were isolated from the ensiled SMS based on the LAB counts and pH tested. Then, a total of 16 strains which rapidly produce lactate and decreased the pH, were selected for a screening test. The optical density (OD), pH, and yellow clear zone were tested for the selected 16 strains. Among the strains, KU5 strain had wider yellow clear zone and lower pH and KU13 strain had higher OD at 24 hr of incubation and wider yellow clear zone compared to other strains and control strain (Lactobacillus plantarum KCCM 12116). Accordingly, KU5 and KU13 strains were finally selected. The KU5 and KU13 were identified as Lactobacillus plantarum by the 16S rRNA sequencing. The KU5 strain was named as Lactobacillus plantarum KU5, and the KU13 strain was named as Lactobacillus plantarum KU13. Lactobacillus plantarum KU5 and Lactobacillus plantarum KU13 were registered at the National Center for Biotechnology Information (NCBI). Access number of Lactobacillus plantarum KU5 was HQ542227 and that of Lactobacillus plantarum KU13 was HQ542228. The optimal medium conditions for growth of KU5 and KU13 were soybean meal 2% and formulated feed 2%, respectively.