• BMB Reports
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• 제38권3호
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• pp.307-313
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• 2005

Thiobacillus ferrooxidans is one of the most important bacterium used in bioleaching, and can utilize $Fe^{2+}$ or sulphide as energy source. Growth curves for Thiobacillus ferrooxidans have been tested, which show lag, logarithmic, stationary and aging phases as seen in other bacteria. The logarithmic phases were from 10 to 32 hours for Thiobacillus ferrooxidans cultivated with $Fe^{2+}$ and from 4 to 12 days for Thiobacillus ferrooxidans cultivated with elemental sulphur. Differences of protein patterns of Thiobacillus ferrooxidans growing on elemental sulphur and $Fe^{2+}$ separately were investigated after cultivation at $30^{\circ}C$ by the analysis of two-dimensional gel electrophoresis (2-DE), matrix-assisted laser desorption/ ionization (MALDI)-Mass spectrometry and ESI-MS/MS. From the 7 identified protein spots, 11 spots were found more abundant when growing on elemental sulphur. By contrast 6 protein spots were found decreased at elemental cultivation condition. Among the proteins identified, cytochrome C have been previously identified as necessary elements of electron-transfering pathway for Thiobacillus ferrooxidans to oxidize $Fe^{2+}$; ATP synthase alpha chain and beta are expressed increased when Thiobacillus ferrooxidans cultivated with $Fe^{2+}$ as energy source. ATP synthase Beta chain is the catalytic subunit, and ATP synthase alpha chain is a regulatory subunit. The function of ATPase produces ATP from ADP in the presence of a proton gradient across the membrane.

• Smart Structures and Systems
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• 제13권2호
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• pp.281-303
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• 2014

In order to suppress the wind-induced vibrations of the Canton Tower, a pair of active mass driver (AMD) systems has been installed on the top of the main structure. The structural principal directions in which the bending modes of the structure are uncoupled are proposed and verified based on the orthogonal projection approach. For the vibration control design in the principal X direction, the simplified model of the structure is developed based on the finite element model and modified according to the field measurements under wind excitations. The AMD system driven by permanent magnet synchronous linear motors are adopted. The dynamical models of the AMD subsystems are determined according to the open-loop test results by using nonlinear least square fitting method. The continuous variable gain feedback (VGF) control strategy is adopted to make the AMD system adaptive to the variation in the intensity of wind excitations. Finally, the field tests of free vibration control are carried out. The field test results of AMD control show that the damping ratio of the first vibration mode increases up to 11 times of the original value without control.

• 한국버섯학회지
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• 제5권3_4호
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• pp.98-102
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• 2007

왕송이버섯의 인공재배법을 개발하기 위하여 농업과학기술원에서 보존중인 MKACC50852 등 4개 균주를 사용하였으며 우선 이들의 RAPD 분석을 통한 유전적 다형성을 분석하여 유사도를 알아보았다. 일본에서 수집한 MKACC50852균주와 인천에서 채집한 자생균주인 MKACC53368이 높은 유연관계를 보였으며, 제주도에서 채집한 MKACC50853은 태국에서 수집한 MKACC53359와 높은 유연관계를 보였다. 왕송이버섯의 인공재배 방법을 개발하기 위해 봉지재배 및 상자매몰 재배를 비교 실험한 결과, 봉지재배가 상자재배보다 초발이소요일수가 빨랐으며 발이정도에서는 큰 차이는 보이지 않았다. 균주별 자실체 발생에서 MKACC50852 및 MKACC53368는 버섯이 발생되었으며 그 외의 균주는 버섯이 발생하지 않았다. 특히, MKACC50852가 자실체의 품질 및 발이율이 가장 높았으며 복토 후 균상생장도 양호하였다. 왕송이버섯의 재배사내 습도별 자실체 생장율은 발이 후 습도를 80%이상 유지 시 자실체 생장율이 좋았으며, 복토 후 균사생장 완료전 약 70%정도 균사 생장시 하온 처리에 의한 발이유기가 효과적이라고 생각되며 발이유기 및 자실체 생장시 주야간 온도편차 유지가 가능하고 환기가 용이한 재배사가 적절하다고 판단된다. 왕송이버섯의 간편한 재배 체계를 확립하고자 폐면 및 톱밥배지를 사용하여 상자재배와 봉지재배시 미강, 밀기울 등 첨가제를 각각 3, 5, 7%씩 처리하여 자실체발생 및 수량을 조사한 결과, 첨가제 중 미강 처리구보다는 밀기울 처리구에서 균사생장이 양호하였으며 배양기간과 발이기간도 단축되었으나, 수량은 폐면 단용구에 비해 낮았다. 균주별로는 MKACC50852 균주가 폐면단용구에서 발이 및 수량(455g/봉지)이 가장 양호하였으며 MKACC53359는 비록 수량은 낮은 편이었으나 처리별로 고른 발이율을 보였다. 결론적으로, 왕송이버섯 자실체 발생을 위해서는 첨가제의 종류보다는 재배환경요인이 더 큰 영향을 준다고 생각된다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.352-352
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• 2017

Recently, the South Korean government encourages the cultivation of upland crops in the paddy field to maintain an adequate level of rice production and then to balance the demand and supply of rice. This is mainly because the rice consumption per capita per year has continued to decline from 135 kg in 1979 to 61.9 kg in 2016, although the rice production was relatively stable. As a result, the rice overproduction became a big social problem. As a part of that, various upland crops such as soybean, maize, minor cereals and forage crops are planted in the paddy field 10 years ago. The cultivation of these crops may settle the problem of short supply and mass import of the crops to some extent. However, a systematic remote observation of upland crops in the paddy field is very scarce. This study investigated the cultivation status of upland crops and any changes of crop harvesting in the paddy field by using an unmanned aerial vehicle (UAV). Also, we analyzed the kind of upland crops and cultivation area in the paddy field by utilizing time series observation images. A fixed wing UAV is used for the investigation. This is because it is easy to use the flight operation and to control flight management software, and it can automatically cope with various emergency states such as a strong wind and battery discharge. The material of UAV is expanded polypropylene, which has an advantage of less equipment damage and risk during takeoff and landing. We acquired observed images in Buljeong-myeon, Goesan-gun, Chungcheongbuk-do, South Korea by using fixed wing UAV in 2015 and 2016. The total investigated area reaches 6,045 ha, and among them the agricultural area was 1,377 ha. For the next step, we created an orthoimage from all images taken using Pix 4D mapper program. According to the results of image analyses in 2015, the paddy field covered total 577 ha (75.9%) with crop plant. The cultivation area of beans, ginseng, maize, tobacco and peach was 256 ha (36.6%), 63 ha (9.2%), 37 ha (5.4%), 31 ha (4.5%) and 27 ha (3.8), respectively. And in 2016, the total covered area was 586 ha (77.1%), and it was comprised of 253 ha (35.5%), 88 ha (12.3%), 29 ha (4.1%), 22 ha (3.1%) and 32 ha (4.5%) in the same order. In this study, we focused on identifying the paddy field which was converted to the cultivation of upland crops by using UAV. And, it has been indicated that the cultivation area of rice decreased from 141 ha in 2015 to 127 ha in 2016, although that of ginseng increased by 25 ha. As a result, it is expected that a lot of paddy field could be replaced by high-income crops such as ginseng and fruit tree (peach) instead of relative low-income rice. More specific and widespread research on the remote sensing in the paddy field needs to be done.

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1603-1611
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• 2009

High-cell-density cultivation of yeast was investigated using the agricultural waste products corn steep liquor (CSL) and molasses. The Saccharomyces cerevisiae KV-25 cell mass was significantly dependent on the ratio between C and N sources. The concentrations of molasses and CSL in the culture medium were statistically optimized at 10.25% (v/v) and 16.87% (v/v), respectively, by response surface methodology (RSM). Batch culture in a 5-l stirred tank reactor using the optimized medium resulted in a cell mass production of 36.5 g/l. In the fed-batch culture, the feed phase was preceded by a batch phase using the optimized medium, and a very high dried-cell-mass yield of 187.63 g/l was successfully attained by feeding a mixture of 20% (v/v) molasses and 80% (v/v) CSL at a rate of 22 ml/h. In this system, the production of cell mass depended mainly on the agitation speed, the composition of the feed medium, and the glucose level in the medium, but only slightly on the aeration rate.

• 농약과학회지
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• 제2권2호
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• pp.90-96
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• 1998

곤충 병원균을 미생물 살충제로서 이용하기 위한 대량배양 기술을 확립코자 미생물 살충제로 잠재성이 있는 Metarhizium anisopliae var. majus ARS 978의 대량배양을 위해 액체배양 조건을 확립하였다. 최적배양을 위한 온도와 pH는 각각 $28^{\circ}C$와 pH 7.0 이었다. M. anisopliae ARS 978의 균체량, 효소들의 활성 및 포자의 생성에 1.0 %(v/v) molasses, 1.0%(w/v) 주박, 0.3 %(w/v) $CaCO_{3}$가 가장 적합한 최적배지 조건이었다.

• Ocean and Polar Research
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• 제35권4호
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• pp.407-414
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• 2013

One of the most important challenges facing the Spirulina mass cultivation industry is to find a way to reduce the high production costs involved in production. Although the most commercial medium (Zarrouk's medium) for Spirulina cultivation is too expensive to use, it contains higher amount of $NaHCO_3$ (16.80 g $L^{-1}$), trace metals and vitamin solutions. The purpose of this study was to increase the efficiency of Spirulina platensis biomass production by developing a low-cost culture medium at an isolated tropical island such as Chuuk State, Federated States of Micronesia (FSM). This study set out to formulate a lowcost medium for the culture of S. platensis, by substituting nutrients of Zarrouk's medium using fertilizer- grade urea and soil extract with a different concentration of carbon source under natural weather condition. In order to select a low-cost culture medium of S. platensis, 10 culture media were prepared with different concentrations of nitrogen (urea and $NaNO_3$) and $NaHCO_3$. The highest maximum specific growth rate (${\mu}max$) and mass production were 0.50 $day^{-1}$ and 1.05 g $L^{-1}$ in modified medium ($NaHCO_3$ 7.50 g $L^{-1}$, urea 2.00 g $L^{-1}$ without $NaNO_3$) among all the synthesized media. Protein (56.14%) and carbohydrate (16.21%) concentrations of the lyophilized standard samples were estimated with highest concentration of glutamic acid (14.93%). This study revealed that the use of a low concentration of urea and $NaHCO_3$ with soil extract was an affordable medium for natural mass cultivation in the FSM.

• 식물병연구
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• 제12권2호
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• pp.85-90
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• 2006

차나무 겹퉁근무늬병을 일으키는 Pestalotiopsis longiseta에 대하여 강력한 길항능력을 나타내는 Bacillus subtilis BD0310 균주의 대량배양을 위한 배양조건과 P. longiseta에 대한 항균활성을 증대시킬 수 있는 탄소원과 질소원을 선발하였다. B. subtilis BD0310 균주를 대량배양하기 위한 최적온도 및 시간은 $30^{\circ}C$, 24 시간인 것으로 확인되었으며, 초기 최적 pH 는 7 로 확인되었다. B. subtilis BD03l0 균주를 대량으로 배양할 경우 P. longiseta에 대한 항균활성을 가장 높게 증가시키는 탄소원을 선발하기 위하여 fructose, galactose, glucose, glycerol, inositol, lactose, maltose, sorbitol, starch 등 9 가지 탄소원을 사용하여 조사한 결과 maltose와 inositol이 가장 효율적인 탄소원으로 선발되었으며, casein, tryptone, malt extract, yeast extract, $(NH_4)_2SO_4$등 5 가지 질소원 중에서 yeast extract와 tryptone이 가장 효율적인 질소원으로 선발되었다. 이러 한 결과들은 길항세균 B. subtilis BD0310를 차나무 겹둥근무늬병 방제용 미생물제제로 개발하기 위한 대량배양생산 공정을 확립하는데 기여할 것으로 전망된다.

• 한국균학회지
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• 제36권1호
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• pp.98-100
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• 2008

자작나무버섯은 자작나무류 수종에 발생하는 버섯으로 상업적 가치가 있는 것으로 판단되나, 우리나라에서는 매우 드물게 발생하고 있어 물박달나무를 이용하여 원목재배를 시도하였다. 자작나무버섯은 4월에 균 접종 후 2년차의 8윌초에 버섯을 형성하여 10월에 성숙하였다. 버섯은 골목 1개당 1개 또는 2개 발생하여 생중량 $212{\sim}1,298\;g$을 수확하였다. 그래서 자작나무버섯의 원목재배는 자실체 대량 생산이 가능하며 버섯을 이용한 새로운 연구가 기대된다.

• 한국미생물·생명공학회지
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• 제48권3호
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• pp.337-343
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• 2020

Haematococcus sp.를 대상으로 mixotroph 형태에서 배양을 위한 배지 최적화 연구를 수행하였다. 기본 배지로는 modified MS 배지가 적절했으며, 탄소원으로는 glucose가, 그리고 농도는 10 g/l가 적합하였다. 질소원으로는 KNO₃를 선정하였으며, 농도는 1.9 g/l이 최적이었다. 최적의 배지조건에서 Haematococcus sp.를 초기 접종량(0.18 g/l)로 접종하여 14일 후에 5.58 ± 0.25 g/l로 성장하였으며, 이는 건조 세포중량 기준으로 약 31배의 성장한 것이다. 이때 생성된 클로로필은 172.16 ± 7.79 mg/l였으며, 카로티노이드는 42.33 ± 1.91 mg/l이었다. 본 연구의 결과는 추후 미세조류 대량 배양과 대사산물의 생산에 이용가능한 기초자료가 될 수 있을 것이라 판단된다.