• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.343-349
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• 1991

Formation of charge transfer complex between iodine and substituted aniline [aniline, N,N-dimethylaniline(N,N-DMA), 2,6-dimethylaniline(2,6-DMA), 2,4,6-trimethylaniline(2,4,6-TMA)] in CHCl$_3$, CH$_2$Cl$_2$ : CHCl$_3$ (1 : 1), and CH$_2$Cl$_2$ have been studied kinetically by using conductivity method. In the transformation of initially formed outer charge transfer complex to inner complex, the effects of substituted aniline as electron donor and polar medium on the reaction were investigated. The rate of transformation depend on the dielectric contribution of medium and pK$_a$ value of substituted aniline. The order of rate increasing is 2,4,6-TMA, 2,6-DMA, aniline, and N,N-DMA. The activation enthalpy ${\Delta}H^{\neq}$ for 2.5 M-substituted aniline in CHCl$_3$ at 25$^{\circ}C$ is respectively N,N-DMA, 3.47 kcal/mol; aniline, 4.25 kcal/mol; 2,6-DMA, 7.79 kcal/mol and 2,4,6-TMA, 7.96 kcal/mol; and activation entropy ${\Delta}S^{\neq}$ is large and negative value of -41 ~ -55 cal/mol${\cdot}$K.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.489-495
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• 1998

The optimum culture condition of Scopulariopsis brevicaulis for the production of ${\alpha}$-galactosidase was as follows: Tryptone 1.5%, $NH_4NO_3$ 0.2%, Raffinose 2.5%, $KH_2PO_4$ 0.5%, yeast extract 0.5%, pH 7.0, $27^{\circ}C$. The optimum pH and temperature for the enzyme activity of ${\alpha}$-galactosidase producing Scopulariopsis brevicaulis were pH 7.0 and $27^{\circ}C$, respectively. The enzyme was relatively stable at $pH\;6.0{\sim}8.0$ and at temperature below $40^{\circ}C$. The activity of the enzyme was inhibited by $Ag^{2+},\;Hg^{2+},\;Cu^{2+}$, p-chloromercuribenzoic acid and Iodine. These results would indicate the presence of -SH groups in the catalytic site of the enzyme. Km value was 1.9 mM for $p-nitrophenyl-{\alpha}-D-galactopyranoside$ and Vmax value was $9.66{\times}10^2\;{\mu}M/min$. Sugar constituents of culture broth were identified by HPLC that the enzyme liberated sucrose, glucose and fructose from raffinose and raffinose was significantly decreased.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.469-478
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• 2008

In this study, degree of rancidity and trans fatty acid formation were examined in fat and oils, including soybean oil (SB), canola oil (CA), corn germ oil (CO), olive oil (OL), palm oil (PO), and beef tallow (BT), during heating for 10-130 minutes at 160-200$^{\circ}C$. In order to determine the rancidity of the fat and oils, acid values (AV), iodine values (IV), viscosity, and color were measured. Changes in the amounts of fatty acids and the formation of trans fatty acids were measured using GC and HPLC. For all groups, AV increased, IV decreased, and coefficients of viscosity and color increased as the heating temperature and heating time increased, indicating there were positive correlations between the heating temperature and time and AV. In addition, all groups had similar amounts of trans fatty acids, with the exception of the beef tallow; however, its level only slightly increased with heating. The olive oil had the lowest trans fatty acid content and the lowest amount created by heating. The order of trans fatty acid amounts generated while heating was BT>PO>CO>CA>SB>OL. According to the study results, the deep frying temperature during cooking should be 160-180$^{\circ}C$ in order to reduce AV and the amount of trans fatty acids that are formed. In addition, it is better to remove beef tallow during cooking and avoid heating at high temperatures since it results in high levels of trans fatty acids. The correlation between the amount of trans fatty acids and AV was positive, while the correlation between the amount of trans fatty acids and IV was negative, indicating that AV and trans fatty acid levels increase while IV decreases as the deep frying temperature and time increase. From the results, it was found that reducing the deep frying temperature and time can lessen increases in AV and trans fatty acids, and decrease IV. Accordingly, to reduce AV and trans fatty acid formation, the ideal deep frying conditions would be to use olive oil or soybean oil rather than beef tallow or palm oil at a temperature of 160-180$^{\circ}C$.

• Journal of Korean Society on Water Environment
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• v.26 no.3
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• pp.491-496
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• 2010

This study aimed to obtain equilibrium concentration on adsorption removal of phosphorus by activated carbon, to express the adsorption characteristics following Freundlich isotherm and also, based on the value obtained, to investigate the relationship between physical properties of activated carbon and dynamics of phosphorus removal by obtaining rate constant and effective pore diffusivity. The results summarized from this study are as follows. Phosphorus adsorption equilibrium reaching time of powdered activated carbon was reduced as the dosage of activated carbon increases, while granular activated carbon despite increased dosage did not have influence on adsorption equilibrium reaching times of phosphorus as well, taking more than 10 hours. It was also noted that powdered activated carbon showed better adsorption ability than granular activated carbon. The value of constant (f) of Freundlich isotherm of powered activated carbon on phosphorus was 4.26 which is bigger than those of granular activated carbon. The adsorption rate constant on phosphorus of powered activated carbon with low effective diameter and iodine number was highest as $8.888hr^{-1}$ and the effective pore diffusivity ($D_e$) was lowest as $2.45{\times}10^{-5}cm^2/hr$, and the value of phosphorus adsorption rate constant of granular activated carbon was $0.174{\sim}0.372hr^{-1}$, It was revealed that, with the same amount of dosage, the adsorptive power of activated carbon with lower effective diameter was better and its rate constant was also high.

• Korean journal of food and cookery science
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• v.2 no.1
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• pp.11-16
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• 1986

Physicochemical properties and fatty acid composition of 12 randomly selected Korean margarines were determined, which were stored within one month since manufactured. Average moisture and fat contents of margarines were 15.09% ana 77.92% respectively. Melting point was ranged from 33.23$^{\circ}C$ to 42. 13$^{\circ}C$. Acid value and peroxide value were very low. iodine value was ranging from 59.65 to 86. 05. As a result of cluster analysis using the data of fatty acid composition, margarines divided into two groups according to their package condition, soft and hard type, were also classified into the same two groups. This probably implies that the raw materials of margarines between two groups were not the same. O1eic acid (18:1) and palmitic acid (16:0) in soft and hard type margarines respectively were the highest. Linoleic acid (18 : 2) contents showed large differences among margarines. Most of the margarines had little linolenic acid (18:3) . Generally essential fatty acid contents of Korean margarines were higher than those of the past but they didn't reach the levels of margarines made in some foreign countries.

• Korean journal of food and cookery science
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• v.8 no.2
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• pp.95-105
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• 1992

This study was carried on the Seasoning Oil production by Autoclaving Method in order to research a developed method. The Raw, Extract states of seasoning vegetables-Garlic, Onion and Ginger were added 40, 60% (w/w) of total amounts to corn salad oil. All samples treated with various conditions were determined physicochemical characteristics by Acid value, Peroxide value, Iodine value, Refractive Index, and Volatile Carbonyl Compound Content during incubating $(40{\pm}2^{\circ}C)$ and heating $(185{\pm}2^{\circ}C)$. The results were obtained as follws; 1. During incubation at $40{\pm}2^{\circ}C$, the order of antioxidative effects among seasoning vegetables was Ginger>Garlic>BHA>Onion and Extract state were more effective man Raw state. also the antioxidative effects of the seasoning vegetables were increased proportionally with the concentration in the Seasoning Oils. 2. In the case of heat treatment $(185{\pm}2^{\circ}C)$, AV, POV, IV and RI of each Seasoning Oil were changed very sharply. The antioxidative effect and Carbonyl Compound Content according to heat treatment differed from the type and concentration of seasoning vegetables in oil. Ginger had the most excellent antioxidative effect among seasoning vegetables, and m any case, the adding states of seasoning vegetables into oils were more effective in Extract man Raw states. 3. According to those results, each Seasoning Oil made from Garlic, Onion, Ginger was shown to have antioxidative properties specially in Ginger-Extract-Seasoning Oil. also the Autoclaving Method was thought to be rational method in preparation of Seasoning Oil.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.3
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• pp.400-406
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• 2014

Apios (Apios americana Medikus) belongs to Leguminosae and is called 'American groundnut', 'Potato bean', and 'wild bean'. Apios is native to the Northern United States but is not widely distributed in Korea. In this study, cross-linked apios starch was prepared by reaction with epichlorohydrin, followed by characterization. FT-IR spectroscopy confirmed the degree of cross-linking of apios starch. X-ray diffraction patterns of native apios showed typical 'A' type as peaks at 15.1, 17.1, 17.9 and $23.2^{\circ}$, and cross-linking did not affect relative crystallinity and X-ray diffraction patterns of the starch. Scanning electron micrographs showed that apios starch granules were smooth with a globular shape, and there was little damage to starch granules after cross-linking. The lightness value of cross-linked apios starch was lower than that of native apios starch, whereas the redness value was not significantly different between cross-linked apios starch and native apios starch. Blue value showed that cross-linking of starch did not affect the iodine reaction of starch.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.120-127
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• 2000

Deep-fat frying is a common cooking practice. There has been considerable concern regarding the mutagenic and carcinogenic potential of thermally oxidized oils. Studies on deep-fried foods so far have revealed not much on the mutagenicity of the oils in the foods. Therefore, in the present study, it was attempted to investigate the mutagenicity ofthe thermally oxidized safflower oil. Oil was heated in a home-fryer at a temperature of 180$\pm$3$^{\circ}C$ for 48 hours. Oil samples were taken at 0, 8, 16, 24, 32, 40 and 48 hours of heating, respectively. Each sample was used to study the changes in peroxide value (POV), acid value (AV), iodine value (IV), conjugated dienoic acid (CDA) content, %, and fatty acid composition. Another series of samples were fractionated into non-polar and polar fractions by column chromatography. The mutagenicity of the samples taken from the thermally oxidized oils, as well as the non-polar and polar fractions of the thermally oxidized oils, was investigated with the Ames test. The Ames test was carried out with and without metabolic activation. Bacterial tester strains used in the present study were the histidine auxotrophic strains of Salmonella typhimurium TA100, TA1535 and TA102 were used for the detection of base pair mutations, and TA98 and TA1537 for frame shift mutations. Each series of samples was dissolved in tetraphydrofuran (inhibitor-free) and tested at doses ranging from 0.05 to 5 mg/plate. None of the oil samples taken during the 48 hour oxidation period showed any mugagenic activity. This was the case, even after the activaton with 59 mix. Also, none of the polar and non-polar fractions showed any mutagenic activity on all the strains tested.

• Journal of the Korean Society of Radiology
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• v.13 no.4
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• pp.653-659
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• 2019

The purpose of this study is to measure the (air dose rate of radiation dose) the discharged patient who was administrated high dose $^{131}I$ treatment, and to predict exposure radiation dose in public person. The dosimetric evaluation was performed according to the distance and angle using three copper rings in 30 patients who were treated with over 200mCi high dose Iodine therapy. The two observer were measured using a GM surverymeter with 8 point azimuth angle and three difference distance 50, 100, 150cm for precise radion dose measurement. We set up three predictive simulations to calculate the exposure dose based on this data. The most highest radiation dose rate was showed measuring angle $0^{\circ}$ at the height of 1m. The each distance average dose rate was used the azimuth angle average value of radiation dose rate. The maximum values of the external radiation dose rate depending on the distance were $214{\pm}16.5$, $59{\pm}9.1$ and $38{\pm}5.8{\mu}Sv/h$ at 50, 100, 150cm, respectively. If high dose Iodine treatment patient moves 5 hours using public transportation, an unspecified person in a side seat at 50cm is exposed 1.14 mSv radiation dose. A person who cares for 4days at a distance of 1 meter from a patient wearing a urine bag receives a maximum radiation dose of 6.5mSv. The maximum dose of radiation that a guardian can receive is 1.08mSv at a distance of 1.5m for 7days. The annual radiation dose limit is exceeded in a short time when applied the our developed radiation dose predictive modeling on the general public person who was around the patients with Iodine therapy. This study can be helpful in suggesting a reasonable guideline of the general public person protection system after discharge of high dose Iodine administered patients.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.99-110
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• 2018

In this study, oil of Platycodon grandiflorum seeds was prepared using supercritical carbon dioxide extraction (SCE) and its physicochemical indices as a new edible oil were investigated. Compared to Soxhlet solvent extraction, SCE under the condition of 6,000 psi at $40^{\circ}C$ produced more oil, especially from the roasted seeds to 32.7%. TLC analysis showed triacylglycerols accounted for most of the oil obtained from roasted Platycodon grandiflorum seeds by SCE similarly to commercial soybean oil or perilla seeds oil. The oil had highly unsaturated lipid with considerable amount of linoleic acid(73.27%) much more than two commercial oils followed by oleic acid(13.16%). Physicochemical properties of the oil were as follows; specific gravity, 0.92; dynamic viscosity, 45.37 cP; refractive index, 1.48; color, L=47.30, a=-3.69, b=25.72; iodine value, 141.57 g $I_2/100g$ oil; saponification value, 191.21 mg of KOH/g of oil; acid value, 2.60 mg of KOH/g of oil. Among those, refractive index, viscosity and iodine value, which were related to unsaturation degree of lipid, were ranged between those of two commercial oils. The oxidation stability of oil(2.03 hr) was also ranged between less stable perilla seeds oil(1.79 hr) and more stable soybean oil(2.94 hr) based on the induction time measured by Rancimat assay. In addition to extraction yield increase, seeds roasting provided further benefits such as reductions of cholesterol ester content and acid value without change in fatty acid composition. In conclusion, oil was extracted from the roasted Platycodon grandiflorum seeds at high yield by supercritical carbon dioxide and it seemed to have proper characteristics as a edible oil.