• Korean Chemical Engineering Research
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• v.55 no.4
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• pp.567-573
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• 2017

In this work, tungsten oxide ($WO_x$) supported on SBA-15 (mesoporous silica) were prepared and applied for oxidative desulfurization of sulfur compounds in marine diesel containing about 230 ppmw of sulfur concentration. Prepared catalysts were examined by two steps; at first step, oxidation reaction carried out with hydrogen peroxide as oxidant and then the oxidized sulfur compounds were extracted by acetonitrile as solvent. Catalysts were characterized by using X-ray diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy and $N_2$ adsorption-desorption isotherms. Tungsten oxide exists as monoclinic crystal system on SBA-15 and over about 10 wt% of the $WO_x$ loading took the form of multi-layers on SBA-15. The 13 wt% $WO_x$/SBA-15 catalyst exhibite highest activity, achieving about 76.3% sulfur removal in the reaction conditions, such as catalyst amount of 0.1 g, reaction temperature at $90^{\circ}C$, reaction time for 3 h and O/S molar ratio of 10. One time oxidation reaction is enough oxidize the sulfur compounds in marine diesel completely. The repetition experiment of extraction process indicated that sulfur removal could reach 94.4% after 5 times.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.965-970
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• 2003

This study has been performed to develope a method for the simultaneous determination of 1,4-dioxane (DOX), epichlorohydrin (EPC), propylene chlorohydrin (PCH), ethylene chlorohydrin (ECH) and 1,3-dichloro-2-pro-panol (DCP) in polysorbates, chloline chloride, choline bitartrate, modified starch and spices by purge and trapgas chromatography. Experimental design was used to select a suitable trap by measuring the limit of detection (LOD) and to investigate the effect of temperature and salt of extraction, and the percentage of recovery in various matrix. The LOD of DOX, EPC, PCH, ECH and DCP were 1.38$\mu\textrm{g}$, 0.23$\mu\textrm{g}$, 3.30$\mu\textrm{g}$, 3.97$\mu\textrm{g}$, 20.43$\mu\textrm{g}$ respectively, by means of using Vorcarb 3000 trap with 5$0^{\circ}C$ sample sparger. Excluding EPC, the recoveries of target compounds were above 90% in all matrix. Target compounds in polysorbates (17), choline chloride (5), choline bitartrate (5), modified starch (8) and spices (25) were not detected. But 2.5 ppm of DOX was detected in Tween 80.

• Journal of Pharmaceutical Investigation
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• v.36 no.1
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• pp.23-29
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• 2006

A rapid, selective and sensitive reversed-phase HPLC method for the determination of promethazine in human serum was developed, validated, and applied to the pharmacokinetic study of promethazine. Promethazine and internal standard, chlorpromazine, were extracted from human serum by liquid-liquid extraction with n-hexane containing 0.8% isopropanol and analyzed on a Capcell Pak CN column with the mobile phase of acetonitrile-0.2 M potassium dihydrogen phosphate (42:58, v/v, adjusted to pH 6.0 with 1 M NaOH). Detection wavelength of 251 nm and flow rate of 0.9 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^{3}$ factorial design using a fixed promethazine concentration (10 ng/mL) with respect to its peak area and retention time. In addition, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 1-40 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 1 mL of serum was 1 ng/mL, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the quality control samples ranged from 96.15 to 105.40% for promethazine with overall precision (% C.V.) being 6.70-11.22%. The relative mean recovery of promethazine for human serum was 63.54%. Stability (freeze-thaw and short-term) studies showed that promethazine was stable during storage, or during the assay procedure in human serum. However, the storage at $-80^{\circ}C$ for 4 weeks showed that promethazine was not stable. Extracted serum sample and stock solution were not allowed to stand at ambient temperature for 12 hr prior to injection. The peak area and retention time of promethazine were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of promethazine in human serum samples for the pharmacokinetic studies of orally administered Himazin tablet (25 mg as promethazine hydrochloride) at three different laboratories, demonstrating the suitability of the method.

• Journal of Life Science
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• v.25 no.12
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• pp.1362-1369
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• 2015

The goal of this study was done for evaluating stability according to low-temperature storage of kimchi duruchigi supplemented with a hot water extract of Rubus coreanus Miquel (RCM). Total polyphenol and flavonoid contents in the RCM extract prepared from the hot water were detected by 293.34 μg CA/mg and 90.57 μg quecetin/mg, respectively. DPPH and superoxide radical scavenging activities of the extract were showed by relatively high values of 70.63 and 57.87%, respectively. Kimchi duruchigi was designed by control (non-treated), T1 (3% RCM extract), T2 (6% RCM extract), and T3 (0.1% ascorbic acid, a positive control). When compared with control and T3 groups, pHs of T1 and T2 groups supplemented with the RCM extract were gently changed depending on the storage time, and water holding capacities of T1 and T2 groups were improved in comparison with control group. Although meat color showed a tendency to most of increase according to the elapsed time, T1 and T2 groups showed less changes than that of control group. Lipid peroxidation appeared in a little bit changes regardless of the processing and storage days, but protein spoilages in T1 and T2 groups were found by lower changes when compared with the control group. As the results of sensory evaluation, T1 and T2 groups during storage had the better taste, flavor and acceptability than those of control and T3 groups. Therefore, we suggest that kimchi duruchigi supplemented with the RCM extract is a possible of improving the storage stability and product preference.

• Journal of Life Science
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• v.19 no.12
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• pp.1841-1846
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• 2009

Menopause is often associated with the incidence of several chronic diseases including osteoporosis, cardiovascular disease, and obesity. Hormone replacement therapy (HRT) is an effective regimen that has been found to prevent these diseases in postmenopausal women. However, HRT is accompanied by an increased risk of unfavorable outcomes. Therefore, this study was conducted to evaluate the effects of Ecklonia cava, a kind of seaweed, extract on bone turnover markers in symptomatic menopausal women. For this study, the following four groups of 9-week-old Sprague-Dawley rats were evaluated over 6 weeks: normal rats (SHAM), ovariectomized rats (OVX-CON) and ovariectomized rats that were treated with Ecklonia cava extracts. The optimum extraction temperature and solvent of Ecklonia cava were found to be $80^{\circ}C$ and 80% ethanol. We measured the osteocalcin and CTx content, enzyme ALP activity in serum and collagen content in the cartilage, bone, skin and lungs. We found that the levels of indicators of bone metabolism such as ALP, osteocalcin and CTx were lower in rats in the Ecklonia cava extract group than the OVX-CON group. In addition, the collagen contents in the bone, cartilage, skin and lungs decreased in response to ovariectomy, but the levels of collagen were greater in the bone of rats that were treated with Ecklonia cava extract than in the bone of rats in the OVX-CON group. According to these results, we were able to know the effects of Ecklonia cava extract on bone aging in ovariectomized rats. Consequently, we expect Ecklonia cava extract to have an effect on bone aging in postmenopausal women.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.593-599
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• 1999

Substrate specificity of a flow-injection-analysis (FIA)-type biogenic amine sensor with enzyme reactor was determined. The enzyme reactor was prepared with a diamine oxidase immobilized on preactivated chitosan porous beads (Chitopearl) by intramolecular cross-linking via glutaraldehyde. The sensor showed a rapid response to putrescine and a quasi-linear calibration curve was obtained up to 15.0 mM. The optimal pH and temperature of the enzyme reactor system were 7.5 and $35^{\circ}C$. Interferences due to ATP-related compounds and trimethylamine, and the effects of NaCl and amino acids were measured. Inhibitory effects owing to these components could be mitigated by sample extraction with perchloric acid. Polyamines except putrescine were determined by a putrescine calibration range within 26.7%. This system was confirmed as rapid and convenient for biogenic amine determination.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.305-310
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• 1998

Glucosidic bond at the $C_{20}$ position of the sapogenins was hydrolyzed easily in the lower pH, higher temperature and longer time to give prosapogenins and sugars. The glucosidic bond of saponin at the $C_3\;of\; ginsenoside-Rb_1\;$, which is secondary carbon, was relatively stable due to the low electron density of -0.2. But the bond of saponin at the $C_{20}$ position, which is tertiary carbon with the relatively high electron density of -0.3, was liable to be hydrolyzed even in weak acidic solution by the increase of heating time. On the other hand, fresh and white ginseng contained 4.12 mg/g, 13.05 mg/g of citric acid, 0.68 mg/g, 2.18 mg/g of malonic acid, 1.13 mg/g, 3.68 mg/g of oxalic acid, 2.68 mg/g, 8.62 mg/g of malic acid and 0.13 mg/g, 0.46 mg/g of succinic acid, respectively. Ginseng saponins were very stable in ginseng extract neutralized with sodium carbonate or sodium bicarbonate corresponding to the equivalent amount of the total organic acid in the ginseng.

• Journal of Mushroom
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• v.11 no.2
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• pp.53-62
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• 2013

A total of 35 phosphate solubilizing bacterial strains were isolated from waste mushroom bed of Agaricus bisporus in Buyeo-Gun, Chungnam and screened for the production of indole acetic acid (IAA). The best IAA producing strain was identified as Pantoea rodasii using 16S rRNA analysis. In addition to the IAA production, this strain could act as an efficient phosphate solubilizer (1100 ${\mu}g$ $ml^{-1}$ after 5 days of incubation) also. The selected strain was cultured under different conditions in order to assess the optimum conditions for maximum IAA production. The nutrient broth (NB) medium was recorded as the best medium, where the maximum IAA production (229 ${\mu}g$ $ml^{-1}$) was recorded at the start of stationary phase (12 hours after inoculation) of the bacteria growth. The performance of the strain was found to be maximum at the temperature of $30^{\circ}C$ followed by $25^{\circ}C$. IAA production was found to be increased with increasing tryptophan concentration (from 0.1 to 0.6%), however beyond this limit, a slight reduction in IAA production was observed. The strains' ability to produce IAA was further confirmed by extraction of crude IAA and subsequent TLC analysis. A specific spot from the extracted IAA preparation was found corresponding with the standard spot of IAA with same $R_f$ value. The results of HPLC analysis conducted in identifying and quantifying the IAA production more precisely, are in agreement with the results of the assessment done with colorimetric method. As revealed by the results of the pot experiment, the isolated strain could significantly enhance the growth (as measured by shoot and root growth) of mung bean plants compared to that of non-inoculated plants. Therefore it can be concluded that the present strain, Pantoea rodasii has great potential to be used as bio-inoculants.

• Journal of Conservation Science
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• v.29 no.1
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• pp.69-79
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• 2013

This study aims at identifying the variation of physicochemical properties for galena ore in order to use it in understanding of manufacturing techniques in terms of metallurgical method and smelting or refining process for obtaining lead. The ores in the study obtained from the operating mine have been washed and pre-treated for a test. Metallic lead has been extracted by roasting process. The result displays that galena is still in present in the matt despite of exposure to high temperature, over $1000^{\circ}C$. Nearly $11.1g/cm^3$ specific gravity metallic lead has been collected from the refining test of which aim was to remove the remnant galena and a trace of concentrated silver has been identified at the grain boundary. The result suggests that at least one refining process was essential to acquire high purity metallic lead and cupellation had been executed to remove remnant silver.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.575-582
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• 1989

An investigation was carried out to improve the quality and yield of barley tea(water extracts) by modifying the roasting method. The modified methods employed were crushing the barley into 4-10 parts and soaking in water at room temperature for 20 minutes followed by roasting (light brown or dark brown) at $250^{\circ}C$ before boiling with water. The varieties of barley used for this study were Ol-bori(with hulls) and Youngsan-bori(without hulls) and the qualities measured were the physical, chemical and sensory characteristics of roasted barley and its extracts. The results showed that the higher solid yields in barley tea was obtained with an increase in soaking and roasting time. The solid yields increased rapidly with extraction time in boiling water until 30 minutes and then slowed down thereafter. However the intrinsic viscosity of barley tea was reduced by increase in soaking and roasting time. The color of barley tea expressed as Hunter L, a, b values showed that lower L value and higher a and b values were measured for those prepared without soaking and with more extensive roasting. Organoleptic evaluation clearly showed that the sensory quality of barley tea was significantly improved in intensity of odor and taste by crushing, soaking and dark brown roasting.