• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.47-52
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• 1976

Growth inhibition and morphological alteration of Bacillus megaterium NRRL B-1368 in aflatoxin-containing TGY liquid media and its growth restoration in normal media were investigated. Crude aflatoxins $(B_1\;22.7%,\;B_2\;1.6%,\;G_1\;3.6\;%\;and\;G_2\;0.2%)$ at concentrations of more than $20{\mu}g/ml$ inhibited the growth of the microorganism and prevented the formation of septum, resulting in abnormal elongation and disturbance of cell division. The aberrant cells, however, grew normally by septum formation and cell division upon returning to aflatoxin-free culture media. It was, therefore, assumed that aflatoxin affects the function of mesosome related to septum formation in bacteria.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1150-1154
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• 2003

The characteristics of a strain that contaminates the manufacturing of rice vinegar by Acetobacter pasteruianus was invetigated. Conditions for inhibiting pellicle formation and growth of the contaminant, which occurs during static culture and storage, were also observed. Examining the morphological, cultural, and physiological characteristics and measuring the amount of cellulose production during static culture for 14 day, we found that the strain was known to be Acetobacter xylinum. No growth was observed below $10^{\circ}C$ as well as over $40^{\circ}C$. Also, the extent of growth was limited when the concentrations of ethanol, NaCl, and acetic acid were more than 10%, 1.5%, and 7%, respectively.

• Journal of Korea Foresty Energy
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• v.22 no.3
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• pp.49-56
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• 2003

As a part of agricultural utilization of charcoal and pyroligneous acid, the effect of wood carbonization products on the growth of red pepper and soil microorganisms was investigated. The treatment of charcoal and pyroligneous acid provided good growth conditions to microorganisms through neutralizing soil acidity and improving the physicochemical properties of soil. Therefore the density of useful microorganism in the soil has been increased. In the growth of red pepper, the length, diameter, and the fruit numbers of red pepper have been increased by treating with wood carbonization products. It was especially shown that yield has increased about 50% in the fruit number, by treating charcoal 1kg, 1000 time-diluted solution of pyroligneous acid and bacteria, compared with the control. It was estimated that increasing the length of seedling and the diameter of red pepper stem contributed to the resistance against the prerequisites of various environmental changes in open field. Therefore, the final yield would be increased. In the antagonism experiment of red pepper mold (Colletotrichum gloeosporioides), the mold became extinct in the 2- and 10-time diluted solution of pyroligneous acid, compared with the control. On the other hand, their growth speed was delayed in the 100- and 1000 time-diluted solution.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.9
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• pp.1254-1262
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• 2021

Recently, the agricultural environment in Korea is rapidly changing due to the aging and decline of the agricultural population, and in order to solve these problems, it is urgently required to improve the agricultural productivity and reduce the labor force. To solve this problem, a smart farm fused with ICT technology is being proposed as an alternative. In Korea, smart farms are currently mainly used in greenhouses. In this paper, this smart farm technology is to be applied to the cultivation of sprouted ginseng. To this end, we use seedlings (about 1.0g) to grow a solid medium and bed for cultivating sprouted ginseng, a fresh ginseng that is produced in a short period of time (2~3 months) with a clean environment management technology that does not use chemical pesticides and hydroponics in a greenhouse developed. In addition, an IoT-based growth environment management system was developed to monitor the growth process of sprouted ginseng in such an environment and to control driving devices.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.127-142
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• 2023

The management of size and weight, which are the growth information of aquaculture fish in fish-farms, is the most basic goal. In this study, the epoch is defined in fish-farms from the time of stocking or dividing to the time of shipment, and the growth data for a total of three epoch is analyzed from a time series perspective. Growth information such as the size and weight of aquaculture fish that occur over time in fish-farms is compared and analyzed with water quality environmental information and feeding information, and a model is presented using the analysis results. In this study, linear, exponential, and logarithmic regression models are presented using the Box-Jenkins method for size and weight by epoch using data obtained in the field.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.657-659
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• 2022

Hydroponics and aquaponics are attracting attention as they enable automated farm management and stable production thanks to the spread of smart farms. There are issues that need to be addressed in applying smart farm, but one of them is to be able to respond flexibly to demand by automatically deciding when to ship, which requires a method for automatically determining the growth level of crops. In this paper, we focused on the simple fact that the area and volume occupied by crops increase with the growth of them, and showed that it is possible to monitor the growth process of crops with 2D and 3D cameras, and to determine the degree of growth of crops by calculating the area and volume. It is necessary to verify the method by applying it to various environments and crops, but in the case of common crops in hydroponics and aquaponics, it is possible to determine the growth level through the analysis of the acquired image through 2D and 3D camera.

• Journal of Life Science
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• v.16 no.1
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• pp.131-135
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• 2006

Oligopeptide is known to be an essential nitrogen nutrient for bacterial growth. Oligopeptide can be transported into cytoplasm by a specific transport system, Opp system. Opp system is composed of five proteins, which are transcribed by an operon. These are responsible for oligopeptide binding protein (OppA), permease (OppB and OppC) and energy generation system (OppD and OppF), respectively. Previously, we isolated the opp operon from Vibrio fluvialis and constructed the oppA mutant by allelic exchange method. In this study, we investigated the growth pattern and biofilm production under the different growth condition. When the cells were cultivated using brain heart infusion(BHI) medium, the wild type was faster than the mutant in growth during the exponential phase. However, it showed that the growth pattern of two strains in M9 medium is very similar. The growth of wild type showed better than that of the mutant grown at pH 8. At pH 7, there was no an obvious difference in growth. After 5 mM $H_2O_2$ was treated to the cells $(OD_{600}=1.2)$, the cell survival was examined. The oppA mutation did not affect in survivability. In the presence of $10{\mu}g/ml$ polymyxin B, the biofilm production of the oppA mutant was higher than that of the wild type.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.454-464
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• 1986

To find main factors to affect tobacco culture and quality, NC 2326 (Nicotiana tabacum L.) was cultivated in Korea and in the United States under different plant density, fertilization, mulching and curing. Among the chemical characteristics of the both experimental soils, the organic matters were similar concentration in both locations but effective phosphorous contents were higher in Oxford in the United States. Plant height, length and width of the largest leaf, leaf thickness, and midrib ratios were larger in Oxford than in Suwon in Korea. Also they were larger in non mulching system than in mulching system. But the total numbers of the leaves were decreased in non mulching system. The content of nicotine was higher in the plant grown in Suwon than in Oxford. The concentrations of nicotine and sugar tend to increase in mulching system comparing of non mulching system. During the growing, the concentration of non-volatile organic acids was higher in Suwon, while it was lower in cured leaf produced in Suwon. Also the contents of total fatty acids were lower in the harvested leaf grown in Suwon, but not in cured tobacco. Forty three compounds identified among the volatile oils from these experimental samples were quantified. The concentrations of the major components related to the tobacco flavour such as damascone, damascenone, solanone, nor-solanadione, and megastigmatrienones were higher in the cured tobacco produced in Oxford rather than in Suwon.

• Korean Journal of Organic Agriculture
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• v.17 no.3
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• pp.357-370
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• 2009

This experiment was conducted to investigate the effects of compost leachate and concentrated slurry on growth of tomato in hydroponic culture. In process of composting, compost leachate was produced water was through a saturated compost heap. The concentrated slurry was produced by filtration and concentration by membrane process. Filtration of pig slurry was necessary to prevent the hose clogging in hydroponics culture. The treatments of this experiment were consisted of seven different liquid fertilizers; compost leachate(CL), concentrated pig slurry (CS), compost leachate+byproduct(CL+BP), concentrated pig slurry+byproduct(CS+BP), compost leachate 50%+nutrient solution50%(CL+NS), concentrated pig slurry 50%+nutrient solution50%(CS+NS) and nutrient solution(NS) for tomato based on nitrogen content. The chemical nutrient solution was the solution of National Horticulture Research Station for the growth of tomato. The concentration of nutrient solution was adjusted a range of $1.6{\sim}2.0 mS/cm$ in EC. 1. The compost leachate and concentrated pig slurry were low in phosphorus(P), calcium(Ca), magnesium(Mg), but rich in potassium(K). 2. Plant height, SPAD value of tomato was highest in the plot of CS+NS, intermediate in CL, CS+BP, and lowest in 100% concentrated pig slurry. 3. The tomato yield of compost leachate plot was 91% compared with inorganic nutrient solution. The compost leachate solution could be used as a nutrition solution of tomato in organic hydroponics. 4. The growth including plant height, SPAD value, fruit number, fruit weight and yield of tomato in the CL 50%+NS 50% was similar in the control. In conclusion, the mixture solution of 50% pig slurry and 50% nutrient solution could be used as a nutrition solution of tomato hydroponic culture.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.522-527
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• 2004

Barley growing in paddy fields often suffers from wet-injury due to oxygen deficiency in rhizospere caused by excessive water in the soil. This study was conducted to investigate responsiveness of growth, development and anaerobic glycolysis enzymes to acute hypoxia in barley seedlings. Barley seedlings at the third leaf stage were subjected to hypoxia (1 ppm dissolved oxygen) by sparging the culture solution with nitrogen gas for up to seven days. Length and fresh weights of the shoot and root were affected little by hypoxia for up to 5 days. But root dry weight was slightly decreased by hypoxia for 7 days. In the root, alcohol dehydrogenase and lactate dehydrogenase activities increased drastically under hypoxia, reaching at their maximum levels in 3 to 5 days of hypoxia and decreasing slightly thereafter. However, the activities of both enzymes changed little in the shoot. Increases of their activities in the root were contributed by all the isozymes found in barley. These results suggest that barley seedlings first adapt to hypoxia by rapidly activating fermentative glycolysis to stabilize cellular pH and to increase energy production for the following morphological adaptative changes.