• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.193-200
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• 2017

BACKGROUND: Plant growth under smart greenhouse (that is plant factory system) conditions of an artificial light type is significantly depending on the artificial light sources such as a fluorescent lamps or Light-Emitting Diodes (LEDs) with specific spectral wavelengths regardless of the outside environmental changes. In this experiment, characteristics on the growth and compound synthesis of kale seedlings affected by light qualities and intensities provided by LEDs were mentioned. METHODS AND RESULTS: The kale seedlings which developed 3~4 true leaves were exposed by fluorescent lamps or LEDs lights of red (R), blue+white (BW), blue+red (BR) with 50 (L) or $100(H){\mu}mol/m^2/s^1$ photosynthetic photon flux (PPF) under hydroponic culture system of deep flow technique for 50 days. Shoot fresh weight increased under the RH, BWH, and BRH treatments with higher PPF. Shoot elongation of the seedlings decreased, and polyphenol synthesis promoted by the higher light intensity conditions. Sugar synthesis in the leaves was above 2 times greater under the RH treatment of monochromic red light quality with $100{\mu}mol/m^2/s^1\;PPF$ than $50{\mu}mol/m^2/s^1\;PPF$. CONCLUSION: The results show that the control of light quality and intensity in the smart greenhouse conditions with artificial lights significantly affects the growth and compound synthesis in the fresh kale leaves with higher culture efficiency compared to the conventional soil culture under greenhouse or field conditions. Researches on the optimum light intensities of the LEDs with special spectral wavelengths are necessary for maximum growth and metabolism in the seedlings.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.152-159
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• 2017

The purpose of this study was to obtain basic data for using Aronia as a functional food material. The composition of anthocyanin was characterized and quantitated by LC-MS/MS, HPLC, and UV-VIS spectrophotometer techniques, respectively. The anthocyanin content was analyzed by temperature, time, pH, and the addition of citric acid. The UV-VIS spectrophotometer used for analysis of anthocyanin is less accurate than the LC-MS/MS method used in recent years. In the past, cyanidin-3-Glucoside was reported to be a major anthocyanin that contains Aronia. However, LC-MS/MS analysis in this study confirmed cyanidin-3-galactoside to be the major compound. The anthocyanin content of the Aronia powder began to decrease sharply at a temperature of $65^{\circ}C$ or higher when heated for 24 hours. In an aqueous solution of Aronia, the anthocyanin content was reduced by 50% at $65^{\circ}C$ for 10 hours and decreased by 85% at $85^{\circ}C$ within 10 hours. Above pH 8, the anthocyanin content was reduced by more than 50%. The results of this study will provide useful information to maintain anthocyanin content in the manufacturing process of Aronia. It could also be used to ensure the stability of anthocyanins in similar species of berries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.259-266
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• 2011

This study was performed to develop an odor-reduced Korean traditional Cheonggukjang (fermented soybean paste) by adding Job's tears to Cheonggukjang made with soybean (control) only. The study included the determination of best addition percentage of Job's tears versus soybean, sensory evaluation, and aroma patterns and its components as well as proximate composition analyses of Cheonggukjang. Job's tears Cheonggukjang (CAJT) was prepared by inoculating Bacillus subtilis and fermented at $40^{\circ}C$ for 48 hours. Ratios of soybean : Job's tears for Job's tears Cheonggukjang were 1:1, 2:1, 3:1, and 4:1, respectively. In comparison of proximal composition, Job's tears Cheonggukjang was high in moisture and carbohydrates, but low in calorie, fat, protein, ash and amino nitrogen. The pH of CAJT was lower than those of control and conventional Cheonggukjang (CC) sold in the market, and the acidity was the lowest in CC. The color of Job's tears Cheonggukjang appeared the whiter and more yellowish, but less reddish in proportion to contents of Job's tears. The contents of viscous substances were higher in CAJT compared with those of control and CC. The contents of glutamic acid, the major components of viscous substances were lower in CAJT than in control and CC, and the contents of fructose higher in CAJT. The scores of sensory evaluation were the highest in Job's tears Cheonggukjang mixed with soybean : Job's tears=4:1. The aroma pattern of CC analyzed was conspicuously dissimilar to the control and CAJT and also discriminated by electronic nose examination. The pyrazines, volatile compounds peculiar to Cheonggukjang, were found to be lower in CAJT by SPME-GC/MS assay. Additionally, the acetic acid, butanoic acid, and naphthalene causing off-flavor were identified in CC, but not in Job's tears Cheonggukjang. The strength of odor through sensory evaluation was by far the lowest in CAJT among the groups. From the findings, it had shown that Job's tears Cheonggukjang would be produced successfully when the ratio of 4:1 (soybean : Job's tears) is employed. Also, it was proved that appropriate ratio of Job's tears addition makes Cheonggukjang odor-reduced and well accepted by people.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.11
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• pp.603-610
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• 2016

This work studies the synthesis of birnessite (${\delta}-MnO_2$), a catalyst of oxidative-coupling reactions, from the powder of spent alkaline manganese batteries (SABP, <8 mesh) and evaluate its reactivity for 1-naphthol (1-NP) removals. Manganese oxides using commercial reagents ($MnSO_4$, $MnCl_2$) and the acid birnessite (A-Bir) by McKenzie method were also synthesized, and their crystallinity and reactivity for 1-NP were compared with one another. 96% Mn and 98% Zn were extracted from SABP by acid leaching at the condition of solid/liquid (S/L) ratio 1:10 in $1.0M\;H_2SO_4+10.5%\;H_2O_2$ at $60^{\circ}C$. From the acid leaching solution, 69% (at pH 8) and 94.3% (pH>13) of Mn were separated by hydroxide precipitation. Optimal OH/Mn mixing ratio (mol/mol) for the manganese oxide (MO) synthesis by alkaline (NaOH) hydrothermal techniques was 6.0. Under this condition, the best 1-NP removal efficiency was observed and XRD analysis confirmed that the MOs are corresponding to birnessite. Kinetic constants (k, at pH 6) for the 1-NP removals of the birnessites obtained from Mn recovered at pH 8 (${Mn^{2+}}_{(aq)}$) and pH>13 ($Mn(OH)_{2(s)}$) are 0.112 and $0.106min^{-1}$, respectively, which are similar to that from $MnSO_4$ reagent ($0.117min^{-1}$). The results indicated that the birnessite prepared from the SABP as a raw material could be used as an oxidative-coupling catalyst for removals of trace phenolic compounds in soil and water, and propose the recycle scheme of SAB for the birnessite synthesis.

• Sijohaknonchong
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• v.23
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• pp.71-105
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• 2005

Toson-Shibigok(Twelve Songs of Toson) which T'oegye, Yi Hwang, composed has received a lot of attention in terms of its educational implications. These implications have become the essential part of Gojeon Sigas(classic songs and poems), and solid evidence has also been accumulated in the literature. Therefore, the purposes of this study are twofold, that is 1) to explore the impact of T'oegye's fundamental structure of the first education at that time and 2) describe how these educational attitudes will eventually yield meta- educational values. What T'oegye meant by fundamental structure of the first education was that Sijos originated from his own experience should be the vital part of teaching method. One can say that T'oegye's teaching method is more integrative than that of modern literature education in that it includes songs. Not only using his own teaching method, but T'oegye tried to demonstrate his own literary structure to his colleagues and the future generations. In the end, Meta-Education which comprises the heart of recent educational theories well reflects Toegye's theoretical propositions. Rather than giving practical knowledge, his method offers the paradigms of thought patterns and shows the learners' attitudes in approaching the truth. Moreover, T'oegye's teaching method has become a good example to the future generations as well as his contemporary followers. In sum, although a lot of years have passed since he died, T'oegye's Sijo works and life still have invaluable impact on the field of education.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.16-22
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• 2011

In developing soil wetting agent using polyoxyethylene nonylphenyl ether (PNE) and polyoxyethylene castor oil (1:1; v/v), the effect of application rates on changes in concentration of PNE, initial wetting of peatmoss + perlite (7:3) medium, and growth of hot pepper (Capsicum annuum L. 'Knockwang') plug seedlings were investigated. The elevation of application rates of wetting agent increased the amount of water retained by the root media. The treatment of 2.5 $mL{\cdot}L^{-1}$ showed similar water retention to + control ($AquaGro^L$ 3.0 $mL{\cdot}L^{-1}$). Most of the liquid wetting agent (LWA) incorporated during the medium formulation leached out in the first and second irrigation, then it decreased gradually until 10 times in irrigation. In investigation of the influence of LWA on position of water infiltrating into root media, the vertical water movements in treatments of 0.5, 1.0, and 1.5 $mL{\cdot}L^{-1}$ were much faster than those in 0.0 $mL{\cdot}L^{-1}$ (-control), but relative speed of water movement decreased by the elevation in application rate of LWA to 2.0 or 2.5 $mL{\cdot}L^{-1}$. The evaporative water loss of root media that to contained various rate of LWA and irrigated to reach container capacity was the fastest in -control among the treatments and it delayed as the application rate of LWA was elevated. The plant height of 22.2 cm in 0.5 $mL{\cdot}L^{-1}$ and stem diameter of 3.26 mm in 1.0 $mL{\cdot}L^{-1}$ were the highest among the treatments tested. The treatment of 1.0 $mL{\cdot}L^{-1}$ also had the heaviest fresh and dry weights such among treatments tested as 3.08 g and 0.861 g per plant, respectively. The elevated application rate over than 1.5 $mL{\cdot}L^{-1}$ resulted in decreased seedling growth. The results mentioned above indicate that optimum application rate of LWA is 1.0 $mL{\cdot}L^{-1}$.

• Journal of the Korean GEO-environmental Society
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• v.11 no.9
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• pp.39-45
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• 2010

Controlled low strength material(CLSM) is produced by mixing portland cement, fine aggregates, water and chemical admixtures. Sand is the most commonly used as the fine aggregates in the conventional CLSM. It is getting more and more difficult to obtain sand in Korea so it is required that the alternative materials be developed as the replacement of sand. Since the engineering characteristics of coal ash are similar to the sand, it becomes necessary to examine the application of the coal ash as the alternative material for CLSM and as the environment-friendly material. When the results meet the optimum pH level that plants can live, it can be expanded the scale of application of the study on the plant as the important field. This study was subjected to present the method to reduce the pH range of CLSM to a suitable condition that plants can survive. To verify this method, the care of neutralization was conducted by immersing the specimen to Ammonium monohydrogen phosphate. Before curing and neutralization, the maximum pH of developmental CLSM is approximately 11. However, the pH value of developmental CLSM has under 9.5 after peaceful curing and neutralization management.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.615-621
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• 2009

In order to optimize the supercritical fluid extraction (SFE) conditions of volatile components from the strawberry, we conducted an evaluation of the sample preparation and SFE operating conditions. The analysis of the volatile components extracted by a variety of sample preparation protocols led to the identification of 30, 26, 30, and 34 volatile components in fresh, freeze-dried, 30% celite and 70% celite treatments, respectively. The 70% celite treatment was the most effective in extracting the volatile components from strawberry via SFE. Analysis of the volatile components extracted by a variety of SFE operating conditions yielded identifications of 34, 35, 34, and 35 volatile components at 3,000 psi (40, $50^{\circ}C$) and 6,000 psi (40, $50^{\circ}C$), respectively. The extraction yield of alcohols and acids, and the total volatile component contents, were highest under conditions of 3,000 psi and $55^{\circ}C$. Volatile components from the strawberry were extracted via SFE, simultaneous steam distillation and extraction (SDE), and solvent extraction (SE). The analysis of the volatile components extracted via different extraction methods resulted in the identification of 56, 34, and 32 volatile components in the SDE, SFE, and SE extracts, respectively. The total volatile component contents identified in the SDE, SFE, and SE extracts were $20.268{\pm}1.144$, $21.627{\pm}1.215$ and $2.476{\pm}0.177\;mg/kg$, respectively. The SFE extract evidenced higher contents of sweet flavors such as 2-methylbutanoic acid, 2-methylpropanoic acid, and hexanoic acid than the SDE and SE extracts. SFE proved to be the most appropriate method for the extraction of fresh volatile components from the strawberry.

• Korean Journal of Agricultural Science
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• v.42 no.4
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• pp.431-437
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• 2015

Recently, assessment of nitrogen balance has been required for environmental agriculture. Nutrient management using organic matters in farmlands has been strongly required as a means of extending resource-cycling agriculture and reduction of nitrogen balance. Organic matters-derived nutrients and soil-available nitrogen should be necessarily considered to manage nutrient balance in soil-plant system. In this study, we reviewed the amount of N supply according to types of organic matter such as livestock compost and green manure in arable land. In case of applied livestock compost in soil, nitrogen mineralization was influenced by nitrogen amount of livestock manure and mixed materials. And nitrogen mineralization of green manure in arable land was influenced by types of crop and return period of green manure because of change of C/N ratio. Also, nitrogen supply by organic matter in arable land can be changed by environmental factors such as temperature, moisture in soil. Therefore, nitrogen supply according to C/N ratio of organic matter and analysis method for estimation of soil nitrogen supply availability should be evaluated to set up the nutrient management model.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.888-896
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• 1996

This study was conducted to investigate the preservative effects of low molecular weight chitosan with and without other preservatives on kimchi at $10^{\circ}C$ during 12 days of fermentation. The pH and titratable acidity of kimchi with preservatives (PSV) were higher and lower, respectively, than those of control kimchi (CON). The decrease in reducing sugar content was more remarkable in CON than in PSV as the fermentation proceeded. Contents of lactic acid and acetic acid were lower in PSV, especially in kimchi with chitosan dissolved in acetic acid (CH-B) and in the one containing both chitosan and Na-benzoate (CHS) than those in CON. The numbers of total viable cells, Leuconostoc sp. and Lactobacillus plantarum were higher in CON than those in PSV. Sensory firmness and green flavor were significantly lower in CON than in CH-B and CHS. Sourness and staled flavor of CH-B and CHS tended to be lower than those of other kimchi samples.