• 미생물학회지
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• 제50권1호
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• pp.84-86
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• 2014

길항균을 생물 농약으로 개발하기 위해서는 저렴한 산업용 배지를 이용한 대량 생산 체계를 확립하는 것이 중요하다. 본 연구에서는 풋마름병 방제 효과가 뛰어난 Bacillus amyloliquefaciens SKU-78 균주의 배양조건을 확립하였다. 저가의 산업용 기질로는 콩가루와 옥수수 전분 배지가 균 생장에 가장 효과적이었고, 최초 pH 5.5, 배양 온도 $30^{\circ}C$, 교반속도 150-250 rpm의 조건으로 30 L fermenter를 이용한 배양에서 20 시간째에 최대 생균수($1.2{\times}10^{11}$ CFU/ml)에 도달하였다. 저가의 산업용 배지로 배양한 배양액을 관주 처리하였을 때 65%의 발병 억제 효과를 나타냄으로써 SKU-78 균주의 산업용 배지를 이용한 대량배양의 기초가 마련되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1999년도 추계 학술대회지
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• pp.145-167
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• 1999

Our self-sufficiency of food has become less than $30{\%}$ and our nation is highly dependant on world's grain market for food. which is unstable in long term due to the world population growth faster than food production. Therefore, it is a great possibility that food might become a political weapon by way of its global shortage. its purchasing difficulty in international free trade market. and the resultant price rising. Our maximal capability of food production has become the most outstanding problem in the dimension of future food security. It would be the utmost scheme for maximal production of food to realize the maximal utilization of arable land through the enlargement of sufficient farming land and the conversion of rotation system for the more grain production. Extensional enlargement of arable land can be positively executed through the development of farming land in domestic and abroad countries. The readjustment of arable land and the installation or irrigation and drainage system can enforce the farming basement for maximal utilization of arable land through the improved rotation between paddy and upland. The prevention policy against farming land encroachment should be strictly executed through grain production encouragement on resting or marginal lands and regulation of utilization conversion for the other than food production on high grade farming lands. It is also required urgently to develope high yielding and high quality varieties through advanced genetic technology for the improvement of unit area yield, especially of wheat, corn. and soybean we import in large quantity The maximal utilization of arable land for the highest production of food can be realized through rational rotation system, the most adaptable crop cultivation on the suitable land, and the most optimal fertilization through the GIS analysis of agricultural environment information on the basis of the computerized soil resource data on super detailed soil maps(1:5000) surveyed plot by plot of whole nation.

• KSBB Journal
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• 제17권4호
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• pp.333-338
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• 2002

생분해성 고분자 합성물질의 원료가 되는 젖산을 주로 생산하는 균을 김치로부터 분리하였다 SEM을 사용하여 관찰한 분리한 균의 형태는 연쇄간균이었고 165 rRNA sequencing 에 의해 계통발생학적 분석의 결과 Lactobacillus casei KH-1로 명명하였다. 1. casei KH-1는 g1ucose를 젖산으로 98%를 전환시키는 호모발효균이었으며, D(-)와 L(+)-이성질체를 각각 7%와 93%를 포함하는 racemic mixtrure로 젖산을 생산하였다. L. casei KH-1은 다른 lactobacillus속과는 달리 세포의 성장과 젖산의 생산에 기질로서 lactose를 이용하지 못하였지만 glucose의 이용은 이전의 연구들과 비교할 때 효과적이었다. Lactobacillus속의 배양에 사용되는 MRS배지의 질소원을 저렴한 원료 즉, YE와 CSL를 1:1로 첨가한 배지로 대신하여 최대의 젖산수율(1.09 mole .mole$^{-1}$)을 얻어 젖산발효에 효과적인 질소원의 대체가 이루어졌다

• 한국토양비료학회지
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• 제47권4호
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• pp.275-283
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• 2014

The ${\gamma}$-oryzanol, ferulic acid esters, which are well-known for their function on cholesterol lowering and prevention of inflammation, diabetes and cancer, are found in the seeds of cereal crops such as rice, corn, wheat and rye. Among them, rice has been reported to contain the highest ferulic acid esters. Since rice cultivation with green manure as a N source is an environmental friendly agricultural practice, it is necessary to identify and quantify as well as evaluate the variations in these compounds in rice samples as affected by different green manure conditions. A total of ten components of ${\gamma}$-oryzanol were isolated and cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, campesteryl ferulate and sitosteryl ferulate were identified as the major components in Korean rice cultivars, 'Unkwang' and 'Hopum'. Comparing the ${\gamma}$-oryzanol contents of these varieties, 'Unkwang' showed clearly similar pattern with conventional type. With the PLS-DA (partial least squares of discriminant analysis) using SIMCA 11.0 ver., the specific pattern and cluster of ${\gamma}$-oryzanol scores with green manure conditions were confirmed, and thus distinguishing green manure effects were possible.

• 스마트미디어저널
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• 제7권3호
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• pp.51-56
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• 2018

바나나는 유엔식량농업기구가 지정한 세계에서 여덟 번째로 중요한 작물이며, 주요 식량인 밀, 쌀, 옥수수 다음으로 지구상에서 생산량이 네 번째로 많다. 맛뿐만 아니라 영양분도 풍부하며 미래의 주요 식량자원으로도 주목받는 과일이다. 하지만 바나나는 인류의 이기심에서 비롯된 비정상적인 재배방법 때문에 오늘날 멸종위기에 처해 있다. 본 연구의 목적은 교과과정을 통해 농업혁명에 대한 배경 지식이 있는 중 고등학생들에게 바나나 멸종에 관한 정보를 쉽고 흥미롭게 전달할 수 있는 디지털 정보 콘텐츠를 개발하는 것이다. 바나나가 멸종위기에 처하게 된 원인과 과정을 스토리텔링 기법을 활용하여 선형적 구조로 보여줌으로써 사용자들이 흥미를 갖도록 하였다. 또한 여러 단계로 구성된 스토리와 각각의 스토리를 뒷받침하는 정보 그래픽의 관계를 상하로 움직이는 병렬구조를 활용하여 시각화시킴으로써 본 콘텐츠와 사용자 사이의 자연스러운 상호작용이 일어나도록 하였다. 본 연구를 통해 멸종위기 종에 대한 인류의 관심이 증대되기를 기대한다.

• 한국토양비료학회지
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• 제48권5호
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• pp.413-420
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• 2015

Objective of this study was to investigate adsorption characteristics and kinetic models of $NH_4-N$ to biochar produced from rice hull in respective to mitigation of greenhouse gases. $NH_4-N$ concentration was analyzed by UV Spectrophotometer. For the experiment, the soil texture used in this study was sandy loam soil, and application rates of chemical fertilizer and pig compost were $420-200-370kgha^{-1}$ (N-P-K) and $5,500kgha^{-1}$ as recommended amount after soil test for corn cultivation. Biochar treatments were 0.2-5% to soil weight. Its adsorption characteristic was investigated with application of Langmuir isotherm, and pseudo-first order kinetic model and pseudo-second order kinetic model were used as kinetic models. Adsorption amount and removal rates of $NH_4-N$ were $39.3mg^{-1}$ and 28.0% in 0.2% biochar treatment, respectively. The sorption of $NH_4-N$ to biochar was fitted well by Langmiur model because it was observed that dimensionless constant ($R_L$) was 0.48. The maximum adsorption amount ($q_m$) and binding strength constant (b) were calculated as $4.1mgg^{-1}$ and $0.01Lmg^{-1}$ in Langmuir isotherm, respectively. The pseudo-second order kinetic model was more appropriate than pseudo-first order kinetic model for high correlation coefficient ($r^2$) of pseudo-second order kinetic model. Therefore, biochar produced from rice hull could reduce $N_2O$ by adsorbing $NH_4-N$ to biochar cooperated in sandy loam soil.

• 한국농공학회논문집
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• 제61권1호
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• pp.121-130
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• 2019

The purpose of this study is to determine the amount of irrigation water for upland crop growth based on the 30 year of historical rainfall data and the water management guidelines as a reference. Five regions and ten crops were selected by their cultivation size. The changes of soil moisture contents were calculated using daily mean rainfall and irrigation demand. This study assumed that crops are irrigated when the soil moisture contents fell below of the field capacity for more than 5 days, which is the drought condition defined by RDA. The maximum irrigation water requirements was 167.2 mm for chinese cabbage during the growing season, which was followed by corn (112.0 mm), daikon (102.3 mm), spinach (66.1 mm), lettuce (56.7 mm), pepper (46.5 mm), potato (33.9 mm), sweet tomato (27.4 mm), peanut (11.5 mm) and bean (10.3 mm), The results of this study could contribute to providing valuable data to determine the capacity of irrigation facilities and to establish the emergency operation plans under extreme unfavorable weather condition (heat wave, etc.) for crop growth.

• Journal of Microbiology and Biotechnology
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• 제32권4호
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• pp.430-436
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• 2022

Platycosides, Platycodi radix (Platycodon grandiflorus root) saponins, are used as food supplements and exert diverse pharmacological activities. Deglycosylation of saponins enhances their biological efficacy, and deglycosylated platycosides are produced mainly through enzymatic hydrolysis. However, the types of available deglycosylated platycosides remain limited because of a lack of hydrolyzing enzymes that can act on specific glycosides in glycosylated platycosides. In this study, a crude enzyme from Aspergillus tubingensis converted platycoside E (PE) and polygalacin D₃ (PGD3) into deglucose-apiose-xylosylated (deGAX)-platycodin D (PD) and deGAX-polygalacin D (PGD), respectively. The products were identified through LC/MS analysis by specifically hydrolyzing all glucose residues at C-3, and apiose and xylose residues at C-28 of platycoside. The hydrolytic activity of the crude enzyme obtained after the cultivation of the fungus using citrus pectin and corn steep solid as carbon and nitrogen sources, respectively, in culture medium was increased compared with those using other carbon and nitrogen sources. The crude enzyme from A. tubingensis was the most effective in producing deGAX platycoside at pH 5.0 and 60℃. The crude enzyme produced 0.32 mg/ml deGAX-PD and 0.34 mg/ml deGAX-PGD from 1 mg/ml PE and 1 mg/ml PGD3 (at pH 5.0 and 60℃) for 12 and 10 h, with productivities of 32.0 and 42.5 mg/l/h and molar yields of 62.1 and 59.6%, respectively. To the best of our knowledge, this is the first study to produce deGAX platycosides from glycosylated platycosides.

• 농촌계획
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• 제27권4호
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• pp.33-41
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• 2021

Ammonia emission from the agricultural sector contributes almost 78% of total ammonia emission in Korea. The current ammonia emission estimation method from fertilizer application has high uncertainty and needs to be improved. In this study, we propose an improvement method for estimating the amount of ammonia emission from agricultural land with improved spatiotemporal resolution using Farm Manager Registration Information System and criteria for the fertilizer. We calculated ammonia emissions by utilizing the 2020 cultivation area provided by Farm Manager Registration Information System for 55 kinds of upland crops cultivated in the field area of the farmland. As a result, soybeans were the most cultivated field crop in 2020, and the area of cultivated land was surveyed at about 77,021 ha, followed by sweet potatoes 22,057 ha, garlic 20004 ha, potatoes 17,512 ha, and corn 16,636 ha. The month with the highest ammonia emissions throughout the year was calculated by emitting 590.01 ton yr-1 in May, followed by 486.55 ton yr-1 in March. Hallim-eup in Jeju showed the highest ammonia emission at 117.50 ton yr-1.

• 한국버섯학회지
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• 제13권4호
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• pp.314-318
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• 2015

본 연구는 지역 특산물인 감과피를 이용한 버섯배지 개발을 위한 기초자료로서 감과피의 이용 가능성을 검토하고자 수행되었으며 감과피는 경상남도 산청지역에서 곶감을 생산하고 남은 것을 수거하여 건조한 후 사용하였고 공시균주는 ASI 2312를 사용하였다. 대조구는 혼합배지:콘코브:톱밥(220:65:15, v/v)을 혼합한 기본배지를 사용하였고 기본배지 중 혼합배지를 5%, 10%, 15%, 20%, 30%, 40%, 50%의 건조된 감과피 처리구로 대체한 처리구를 시험구로 사용하였다. 대조구인 기본배지에 비해 시험구인 5%, 10%, 15%, 20%, 30%, 40%, 50% 감과피 처리구의 T-N 함량은 감과피 첨가량이 증가할수록 감소하는 경향을 나타내었으며 T-C 함량은 큰 차이가 없었고 C/N율은 감과피 첨가량이 증가할수록 증가하는 경향을 나타내었다. 감과피 첨가량이 균사생장에 미치는 영향을 조사한 결과 대조구보다 감과피가 첨가된 모든 시험구에서 균사생장이 느리게 나타났다. 감과피 첨가량에 따른 배양일수는 대조구인 혼합배지에 비해 감과피를 30%까지 첨가하여도 배양일수와 초발이 소요일수에는 뚜렷한 차이는 없었지만 감과피 첨가량이 증가할수록 배양일이 길어지는 경향을 보였으며 혼합배지에 비해 감과피 첨가비율이 증가할수록 갓의 직경은 감소하고 대의 길이는 길어지고 직경은 감소하는 경향을 나타내었다. 수확 후 동결 건조한 큰느타리버섯의 수분, 단백질, 조회분 함량은 대조구와 시험구에서 유의성 있는 차이를 나타내지 않았지만 조지방 함량은 감과피 첨가량이 증가함에 따라 증가하는 경향을 나타내었고 ${\beta}-glucan$ 함량은 대조구에 비해 10%와 15% 감과피 첨가구에서 높게 나타났다. 따라서 대조구와 비교했을 때 15% 감과피 첨가구는 자실체 수량도 높게 나타나고 ${\beta}-glucan$ 함량도 높게 나타났기때문에 감과피 첨가비율은 15%가 가장 적합한 것으로 사료된다.