• Korean Journal of Environmental Agriculture
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• v.36 no.2
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• pp.113-118
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• 2017

BACKGROUND: The carbon (C) isotope ratio (${\delta}^{13}C$) of dissolved organic C (DOC) is an indicator of water pollution source. In this study, the potential use of two pre-treatments for the ${\delta}^{13}C$ analysis, alkaline persulfate oxidation coupled with carbonate precipitation (precipitation) and freeze drying (drying), were compared to suggest a more feasible pre-treatment method. METHODS AND RESULTS: Two reference materials with different ${\delta}^{13}C$ values were used for the experiments; chemical grade glucose ($-12.0{\pm}0.02$‰) and pig manure compost extract ($-23.3{\pm}0.04$‰). In the precipitation method, the measured ${\delta}^{13}C$ values were consistently lower than the theoretically calculated values as dissolved $CO_2$ could not be removed due to the alkaline property of the reagents and the dissolution of air $CO_2$ into the alkaline solution. The drying method also resulted in more negative ${\delta}^{13}C$ than the calculated ${\delta}^{13}C$; however, the difference was systematic ($3.9{\pm}0.3$‰) and there was a strong correlation (${\delta}^{13}C_{calculated}=0.87{\times}{\delta}^{13}C_{measured}-0.624$, $r^2=0.98$) between the calculated and measured ${\delta}^{13}C$. Calibration of ${\delta}^{13}C$ using the relationship between the calculated and the measured ${\delta}^{13}C$ values produced reliable and accurate ${\delta}^{13}C$ values. CONCLUSION: Our results suggest that the drying method is more accurate pre-treatment method to minimize the influence of air $CO_2$ compared to the precipitation method for the determination of ${\delta}^{13}C$ of DOC.

• Applied Biological Chemistry
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• v.4
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• pp.33-42
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• 1963

1. Two fermentation methods have been compared for the production of Takju (Korean native Sake). One method (S1) uses 'Nuruk' (Korean mold wheat) and the other method (S2) uses 'Nuruk' and mold rice. The chemical analysis of source material, also, have been made in order the check the quantitative changes during the fermentation. The results are summarized below: a. The rate of fermentation was slower for the S2 method than for the S1 method. However, the residual sugar in the S2 method was smaller and the amount of alcohol produced the same as with the S1 method. This was true in spite of the fact that the total initial sugar content for the S2 method was 10 percent below that of S1. b. With both the S1 and S2 methods, 80 percent of the total alcohol production was obtained with in 3 to 4 days. c. The pH value of the base material at the beginning of fermentation was markedly different between the two methods I.e.6.0 to 6.2 for S1 and 4.8 to 5.2 for S2. However, after one or two day the pH of both materials was about the same 4.0 to 4.2 and remained at this value unit the fermentation was complete. 2. Organic acids and Sugars in the source materials have been detected by the paper partition chromatography(p.p.c.) method and the followings are obtained. a. Important Organic acids are Fumalic, malic Succinic, Citric, Acetic aicds in polished rice and Fumalic, Succinic, Acetic, Citric, Malic and Oxalic acids 'Nuruk'. The same kinds of acids as in the rice are found in mold rice, However, amount of Citrice acid is markedly increased in mold rice. b. The important Sugar, Glucose, Fructose and Raffinose in polished rice, Gulcose, Fructo, se, Xylose and one which supposed to be Kojibjose in 'Nuruk'. Glucose and those supposed to be Isomaltose, Kojibiose and Sakebiose and found in rice mold, however, no Sucrose, which was exist in polished rice, was found. 3. The important Organic acids found in fermenting mash using the p.p.c. method were Lactic, Succinic and Acetic. Citric acid identified early in the fermentation, S2 method. remained throughout. However, with the S1 method Cirtic acid was detected only during the late stage of fermentation. Sugars not found in the original materials were two which supposed to be Isomaltotriose and Pentose. Maltose found at the beginning of the fermentation disappeared within one day, Isomaltose was detected throughout the period of fermentation. 4. The Somogyi method which was employed to determine the quantitative changes of sugars in the orginal meterial and mach, showed that polished rice containes in order and in largest amounts Sucrose, Glucose, Raffinose and Fructose. 'Nuruk' contained almost equal quantities of Glucose and Fructose. However, the Glucose content of the mold rice exceeded that originally in the polished rice by 25 or 30 times. Only a small quantity of free sugars was found in the mash at the end of the fermentation.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.205-212
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• 2007

In this work, polyacrylonitrile (PAN) fiber was prepared by electrospinning methods from dimethyl formamide solutions with various conditions, such as 8~20 kV applied voltage, 5~15 wt% PAN concentration, and 15 cm tip-to-collector distance (TCD). The nanofibers were stabilized by oxidation at $250^{\circ}C$ for 1 h, and then subsequently carbonized at $800{\sim}1000^{\circ}C$ for 1 h. The structured characteristics of the nanofibers before and after carbonization were studied by Fourier transform infrared spectroscopy. The resulting diameter distribution and morphologies of the nanofiber were evaluated by scanning electron microscope analysis. The electrochemical behaviors of the nanofiber were observed by cyclic voltammetry tests. From the results, the diameter of electrospinning nanofibers was predominantly influenced by the concentration of polymer solution and the applied voltage. The average diameter of the fibers was decreased with increasing the polymer concentration up to 10wt%. It was also found that the nanofibers with uniform diameter distribution and fine diameter could be achieved at 15kV input voltage and 15 cm TCD.

• Toxicological Research
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• v.21 no.2
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• pp.107-113
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• 2005

[ $BARODON^{(R)}$ ] is a multi-purpose, high functional alkali solution made by mixing and liquid-ionizing silicon, calcium, sodium, borax, organic carbon chemicals and silver. In this study, we have investigated the apoptotic potential and mechanistic insights of $BARODON^{(R)}$ in human gastric cancer cell line (AGS cells). In MTT assay, $BARODON^{(R)}$ reduced cell viability in AGS cells. Morphological features of apoptosis with marked cytoplasmic vacuolation and appearance of apoptotic peaks in flow cytometry were observed in AGS cells with$BARODON^{(R)}$ treatment. In addition, $BARODON^{(R)}$ induced apoptosis of stomach cancer cell is related to bax up-regulation, caspase 7 protease activation and subsequent cleavage of poly (ADP-ribose) polymerase (PARP). These results suggest that BARODON can induce the apoptosis of AGS cells through modulation of bcl-2 family and the activation of intrinsic caspase cascades, indicating that it is potentially useful as a anti-cancer agent.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.404-409
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• 2012

In order to obtain optimum mixing conditions with animal cadaver residue and sawdust for composting using rendering treatment method for agricultural recycling, changes of chemical characteristics and compost quality after composting were investigated. Initial mixing ratios with animal cadaver residue and sawdust were adjusted 100 : 0, 50 : 50 and 30 : 70. Temperature, pH, contents of ammonia and carbon dioxide were rapidly increased in 3 days and then decreased with time. Organic matter content was similar in all conditions. In mixing ratio of 50 : 50, the compost quality was satisfied with compost depending on official standard for product fertilizer. Thus, the optimum mixing ratio of animal cadaver residue and sawdust were 50 : 50.

• Economic and Environmental Geology
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• v.47 no.4
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• pp.381-393
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• 2014

Seismic reflection data are integrated with fieldwork data in order to understand startigraphy, structural geology and hydrocarbon potentials of Cretaceous strata in the Mesopotamian basin, Northeastern Iraq. Cretaceous strata in the basin divided into the Qamchuqa, Kometan, Bekhme and Shiranish formations, which are composed of carbonates deposited in shallow marine environment. The geological structures in these formations are mainly recognized as thrusts, detachment folds, fault propagation folds and fault bend folds. As well, NW-SE trending fractures are regularly developed, and are horizontal or perpendicular to the structures. The distribution and frequency of fractures are related to the development of the thrusts. In terms of hydrocarbon potentials, Cretaceous strata in the basin have limited capacities for source rocks and seal rocks due to the lack of organic carbon content and the well-developed fractures, respectively. Although these carbonates have limited primary porosity, however, development of the secondary porosity derived from the fractures contributes to enhance the reservoir quality. Most important factor for the reservoir quality of Cretaceous strata seems to be the frequency and connectivity of fractures relative to locations of folds and faults. The results delineated in this study will use as reference for recognizing stratigraphy and structures of Cretaceous strata and will provide useful information on hydrocarbon potentials of Cretaceous strata in the Mesopotamian basin, NE Iraq.

• Research in Plant Disease
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• v.18 no.4
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• pp.298-303
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• 2012

Tomato yellow leaf curl virus (TYLCV), transmitted exclusively by the whitefly (Bemisia tabaci) in a circulative manner is one of the most important virus in tomato. Since the first report of TYLCV incidence in Korea in 2008, the virus has rapidly spread nationwide. TYLCV currently causes serious economic losses in tomato production in Korea. Early detection of TYLCV is one of the most important methods to allow rouging of infected tomato plants to minimize the spread of TYLCV disease. We have developed an ultra-rapid and sensitive real-time polymerase chain reaction (PCR) using a new designed real-time PCR system, GenSpectorTM TMC-1000 that is a small and portable real-time PCR machine requiring only a $5{\mu}l$ reaction volume on microchips. The new system provides ultra-high speed reaction (30 cycles in less than 15 minutes) and melting curve analysis for amplified TYLCV products. These results suggest that the short reaction time and ultra sensitivity of the GenSpector$^{TM}$-based real-time PCR technique is suitable for monitoring epidemics and pre-pandemic TYLCV disease. This is the first report for plant virus detection using an ultra-rapid real-time PCR system.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.95-101
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• 2010

Folate loaded WPI (whey protein isolate) nanoparticles were prepared using the cold-induced gelation process. The aim of this work was to investigate the effects of process parameters, such as the concentration of the WPI solution, pH, temperature, etc, on the properties of nanoparticles. The results show that the smallest nanoparticles were obtained when a WPI concentration of 1% was used at a pH of 8.0 (<330 nm). In the case of the concentration of $CaCO_3$, the smallest particles were obtained at a concentration of 5 mM. Alginate produced the smallest mean size with the narrowest particle size distribution, while the largest particles were prepared with k-carrageenan. As the w:o ratio increased, the mean particle size also increased. When the release profile was analyzed, the particles were shown to be stable for more than 6 h at a pH of 1.2, where almost all of the folic acid was released within 2 h in the dissolution media of PBS at a pH of 7.4. Thus, the process parameters appear to be important factors that affect the properties of nanoparticles.

• Journal of Environmental Science International
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• v.26 no.6
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• pp.789-795
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• 2017

Termites (Isoptera) are classified into approximately 3,106 species. In Korea, only one species has been identified, which is Reticulitermes speratus kyushuensis Morimoto. The termite, a social insect, is known to play an important role in nutrient cycling of the ecosystem, although some species of termites are well-known pests attacking wooden structures or any plant materials. However, there is a lack of research about termites in Korea, including aspects such the taxonomy, physiology, and ecology of termites. This study was carried out to provide valuable basic data on the ecological role of termites in an ecosystem in Korea for the future studies. For the experiments, soil and termite samples were randomly collected from Mt. Hwajang located in Jikdong-ri, Eonyang-eup, Ulju-gun, Korea between October 5 and 30, 2015. Analysis results showed that there were no significant differences in soil chemical properties between the soil samples just after air-drying and one year elapsed without any treatment. The treated soil with termites showed significantly higher than the soil without termite treatment. Chemical properties of total nitrogen, organic matter, available phosphate, pH, Calcium(Ca), Potassium(K) and Magnesium(Mg) in soil treated with termites were $1.11{\pm}0.3gkg^{-1}$, $43.3{\pm}12.4gkg^{-1}$, $27.4{\pm}2.9mgkg^{-1}$, $4.56{\pm}0.2$, $0.82{\pm}0.2cmol_ckg^{-1}$, $3.18{\pm}1.4cmol_ckg^{-1}$, $1.73{\pm}1.1cmol_ckg^{-1}$, respectively. The values of soil property of without termite treatment were $0.56{\pm}0.1gkg^{-1}$, $30.5{\pm}3.1gkg^{-1}$, $24.0{\pm}4.7 mgkg^{-1}$, $4.09{\pm}0.1$, $0.71{\pm}0.2cmol_ckg^{-1}$, $2.88{\pm}1.5cmol_ckg^{-1}$, $1.30{\pm}0.7cmol_ckg^{-1}$, respectively. These results suggest that inhabitation of termites could improve soil chemical properties in an ecosystem.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1425-1430
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• 2007

This study investigated alcohol and acetic acid fermentation conditions for the quality control of pomegranate vinegar In the alcohol fermentation process, alcohol content was the highest at a pomegranate juice concentration of $16^{\circ}Brix$, but suitable to fruit vinegar standards at a concentration of $12^{\circ}Brix$. In the concentrated pomegranate juice alcohol fermentation free sugars, fructose and glucose were detected at the beginning of fermentation; at day 4 of fermentation only glucose was detected and decreased as time passed. Organic acids were also detected, including oxalic, lactic, acetic, and citric acid, and they did not change greatly during the alcohol fermentation process. In the acetic acid fermentation process, total acidity increased from 1.56% to 5.54%, where acetic acid increased; however, oxalic, lactic, and citric acids changed only slightly. In conclusion, pomegranate vinegar can undergo alcohol and acetic acid fermentation processes using concentrated pomegranate juice of $12^{\circ}Brix$.