• Title/Summary/Keyword: $\textrm{Mg(OH)}_2$

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Leaching Behavior of LD Slag

  • Kim, Hyung-Suek;Han, Ki-Hyun;M. S. Oh;Byeon, Tae-Bong
    • Proceedings of the IEEK Conference
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    • 2001.10a
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    • pp.526-531
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    • 2001
  • LD slag, that is, a by-product of steel making process, has been mainly used as land construction materials. Recently, the seashore application of LD slag was tried in Japan and Korea tut the reaction between LD slag and seawater was not studied yet. We tried to clarify the leaching reaction and/or mechanism of LD slag and the reaction between seawater and LD slag. We tried to apply these results to the decarbonization of seawater for seawater magnesia process. At first, LD slag was milled and classified into 5 grades, that is, (ⅰ)45${\mu}{\textrm}{m}$ under, (ⅱ)0.25~0.5mm (ⅲ)0.5~1mm(ⅳ)1~2mm, (ⅴ)2.36~3.35mm. These slags were leached in the distilled water. In case of 45${\mu}{\textrm}{m}$ under, the pH of the leached solution was over 12. The chemical analysis of leached solution showed that the $Ca^{+}$$^2$was main component and the S $i^{+}$$^4$was very low. On the other hand, the content of S $i^{+}$$^4$in leached solution was decreased with the increase of pH of this solution. The nearly pure calcium solution was made and the ultra high purity MgO could be made with this calcium solution. The leaching behavior of LD slag was different between the fine particle and coarse particle. The calcium was leached by bulk dissolution in the coarse particle and by surface controlled reaction in fine particle. The leaching rate was slow in coarse particle and fast in fine particle. Therefore, the high pH solution, that is, over 12, was obtained in fine particle.cle.e.

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HPLC Determination and Pharmacokinetics of Endogenous Acetyl-L-Carnitine (ALC) in Human Volunteers Orally Administered a Single Dose of ALC

  • Kwon, Oh-Seung;Chung, Youn-Bok
    • Archives of Pharmacal Research
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    • v.27 no.6
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    • pp.676-681
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    • 2004
  • Acetyl-L-camitine (ALC), a naturally occurring endogenous compound, has been shown to improve the cognitive performance of patients with senile dementia Alzheimer's type, and to be involved in cholinergic neurotransmission. Because ALC is an endogenous compound, valida-tion of the analytical methods of ALC in the biological fluids is very important and difficult. This study was presented validation and correction for plasma ALC concentrations and pharmacok-inetics after oral administration of ALC to human volunteers. ALC concentrations in human plasma were corrected by subtracting the concentration of blank plasma from each sample. Precision and accuracy (bias %) for uncorrected ALC concentrations were below 2.6 and 6.5% for intra-days, and 4.0 and 9.4% for inter-days, respectively. Precision and accuracy (bias %)for corrected ALC concentrations were below 10.9 and 6.0% for intra-days, and 10.5 and 16.9% for inter-days, respectively. Quantitation limit was $0.1{\;}\mu\textrm{g}/mL$. After oral administration of a 500 mg ALC tablet to 8 healthy volunteers, the principle pharmacokinetic parameters were 4.2 h of the half-life$ (t_{1/2},{\beta})$, the area under the curve $(AUC_{0{\rightarrow}8){\;}of{\;}9.88{\;}\mu\textrm{g}{\cdot}h/mL$, and 3.1 h of the time ($T_{max}$) to reach $C_{max}$. This study first describes the pharmacokinetic study after oral admin-istration of a single dose of ALC in human volunteers.

Antimicrobial Activities of Berry Extract of Domestic Plants on 4 Kind of Pathogenic Microorganism (4종의 식품 부패 미생물에 대한 국내산 자생 식물 열매 추출물의 항균성 탐색)

  • 권민경;이해은;박주연;한영숙
    • Journal of the East Asian Society of Dietary Life
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    • v.13 no.5
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    • pp.433-438
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    • 2003
  • To select new useful domestic plants with antimicrobial activities, thirty five samples of berry plant were distributed from Plant Diversity Research Center in Korea Research Institute of Bioscience and Biotechnology. Their extracts with methanol were tested against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, Listeria monocytogenes by paper disc method. The methanol extracts from Viburnum dilatatum, Viburnum erosum, Aralia continentalis, Camellia japonica, Acer trumcatam, Arasaema takesimense and Rhysocarpus intermedius were effective against S. aureus and the results were as follows: Viburnum erosum 6.5 mm, Viburnum dilatatum and Aralia continentalis 7.0 mm, Rhysocarpus intermedius 8.0 mm, Acer trumcatum 9.0 mm, Camellia japonica and Arisaema takesimense 9.5 mm. And only the methanol extract from Camellia japonica was effective against L. monocytogenes, 7.0 mm. Antimicrobial activities of E. coli and S. typhymurium were not detected. The minimum inhibitory concentration(MIC) of berry of Camellia japonica was examined as 1,250 $\mu\textrm{g}$/mL against S. aureus and as 1,250∼2,500 $\mu\textrm{g}$/mL against L. monocytogenes.

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Screening for Antioxidant Activity of Edible Plants (식용식물의 항산화효과 검색)

  • 조세연;한용봉;신국현
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.1
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    • pp.133-137
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    • 2001
  • The antioxidant activitiesof methanol extracts of twenty one vegetables were tested using the method of 1,1-diphenyl-2-picryl hydrazyl (DPPH) reactivity and TBARS substance assay in vitro. The methanol extracts of the leaves from three plants such as Aster scaber, Chrysanthemum coronarium, Petasites japonicus were found to be th most effective on DPPH radical scavenging activity. The next effective ones were the leaves of Capsicum annuum, the peels of Ipomoea batatas and Solanum tuberosum, the stems and leaves of Ipomoea batatas, the levels of Solanum melongena, the fruits of Solanum melongena, the green fruits (seed) of Capsicum ammuum in order, and the others did not show a considerable activity. When tested on lipid peroxidation using a lipid peroxidation generation system mediated by $H_{2}O_{2}/Fe^{2+}$ in rat liver homogenates. the peels of Cucumis melo, the leaves and the fruits of Solanum melongena, of Solanum melongena, The levels of Aster scaber and Chrysanthemum coronarium, the stems and leaves of Ipomoea batatas and the peels of Ipomoea batatas were found to exhibit a good protective activity against lipid peroxidatian in the order of effectiveness.

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Development of Ceramic Media for Yeast Immobilization (효모 고정화용 세라믹 담체의 개발)

  • 이율락;박상재
    • KSBB Journal
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    • v.15 no.3
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    • pp.285-292
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    • 2000
  • Support media for yeast immobilization was prepared from a porous volcanic rock used as a moisturizer in orchid growing. The rock was broken to the size of 2-3 mm and burned at $600^{\circ}C$ in a furnace in order to remove organic materials blocking the pores or treated with HCI solution or NaOH solution to remove the inorganic dirts by dissolving. Even through both the acid and the akali solution were effective the latter was not recommendable because it broke the pore structure by dissolving the elements of the media. This media was mainly consisted of SiO2 with $Al_2O_3$ as a minor component and CaO and K2O as trace elements. It had the finely developed pores of $15-80\mu\textrm{m}$size. Yeast immobilization capacity of this media was about $5{\times108}$ cells/ml bed which is large enough to be used for the practical applications. Yeast immobilization capacities of Alumina and Cordierite were much smaller than that of silica-based media. Scanning electron micrograph of Cordierite and Alumina showed uneven surfaces and small size of pores in contrast to relatively smooth surface and large pores of silica based media which means that smooth surface and large pores are desirable for the good adsorption of microbes on the media.

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Effect of xylazine hydrochloride on histamine release (Xylazine이 histamine 유리에 미치는 영향)

  • 김영환;박준형
    • Korean Journal of Veterinary Service
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    • v.25 no.1
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    • pp.53-73
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    • 2002
  • It has been reported that degranulation of mast cells in rats, rabbits and dog was observed after dosing xylazine hydrochloride(Xh) which has been widely used as sedative, analgesic and muscular relaxant. Therefore, this experiment was conducted to examine the relations between Xh and histamine release and to identify the action of ${\alpha}$-adrenoceptors which exists on the suface of mast cells. 1. The content of histamine within serum was measured with HPLC by performing the O-phthalaldehyde(OPA) fluorescent derivation. The pretreatment method had a little modification from the conventional method. The pretreament was carried out in the following method. 0.2$m\ell$ of serum and 1$m\ell$ of butanol were added to mixed together and then the liquid was centrifugally separated at 4$^{\circ}C$ and 2,000 rpm for 3 minutes. 0.4$m\ell$ of 0.1N HCl and 1.6$m\ell$ of heptane were added to 0.8$m\ell$ of supernatant taken from the liquid, and they were mixed together. This mixture was also centrifugally separated at 4$^{\circ}C$ and 2,000 rpm for 5 minutes. The supernatant was thrown away and the OPA fluorescent derivation was carried out with 0.2$m\ell$ of the lower liquid then, 5 minutes after mixing 400${\mu}\ell$ of 0.1N HCl, 120${\mu}\ell$ of 1N NaOH and 40${\mu}\ell$ of 0.1% OPA in the 0.2$m\ell$ of the lower liquid,120${\mu}\ell$ of 3.57N H$_3$PO$_4$ was added to the mixed liquid, and the liquid, was mixed again and syringe-filtered. Then, the measurement was done with HPLC in the 30 : 70(ν/ν) ratio of 0.004M KH$_2$PO$_4$: CH$_3$CN, flow rate of 1.0$m\ell$/min., and a wavelength of λex= 350nm and λem=444nm at the column temperature of 27$^{\circ}C$, using the fluorescence detector. 2. The content of histamine in each laboratory animal appeared to be higher in such an order as rabbit, rat, guinea pig, dog, Korean indigenous goat, swine, Korean indigenous cattle, Holstein, and mouse, of which the individual mean values${\pm}$standard deviation were 2.0668 ${\pm}$ 0.6049. 0.4999 ${\pm}$ 0.2278, 0.4241 ${\pm}$ 0.1974, 0.1054 ${\pm}$ 0.0556, 0.1028 ${\pm}$ 0.0276, 0.0972 ${\pm}$ 0.0513, 0.0872 ${\pm}$ 0.0373, 0.0717 ${\pm}$ 0.0379, and 0.0706 ${\pm}$ 0.0366, respectively. 3. The content of histamine was measured at the moments of 15-, 30-, 60-, 120-minutes after inoamuscular injection of 20mg/100kg Xh into two to 4 years old Holstein weighing 600∼700kg. The result showed that there was a significant increase at the times of 30- and 90-minutes after injection(p<0.05). 4. Intramuscular injection of 3mg/10kg Xh was given to crossbred pug dogs weighing 2.5∼4.3kg. The content of histamine was measured at the times of 30-, 60-, 90- and 120-minutes after injection. The result revealed that there was a significant increase at the times of 60-and 90-minutes after injection(p<0.05). 5. Intramuscular injection of 10mg/$m\ell$∼25mg/$m\ell$ Xh in concentration of 0.1$m\ell$ was applied to Korean indigenous goat over 5 months old. Then, the content of histamine was measured at the times of 15-, 30-, 60- and 90-minutes after injection. A significant increase was shown at the times of 30- and 60-minutes after injection(p<0.05). 6. The content of histamine was measured at the moments of 30- and 60-minutes after intramuscular injection of 0.1-0.2$m\ell$ Xh (20mg/$m\ell$) into male rabbits weighting 2.5-4kg. A significant increase was found at the moment of 60 minutes after injection(p<0.001). 7. After administering Xh to the mast cell taken from the abdominal cavity of mouse, the content of histamine was measured. The result showed that the higher the concentration, the more significantly the content of histamine was increased(p<0.05). 8. Compound 48/80 was administered in concentration of 5$\mu\textrm{g}$/$m\ell$ and 10$\mu\textrm{g}$/$m\ell$ to the mast cell picked from the abdominal cavity of mouse. The result showed that there was a significant increase in the content of histamine in case of the concentration of 10$\mu\textrm{g}$/$m\ell$(p<0.05). It was found to be about 10,000 to 500,000 times stronger than the Xh. 9. After premedication of 1mg/kg of yohimbine hydrochloride as ${\alpha}$$_2$-adrenergic antagonist to rabbits, the Xh was administered to them. The result was that the value of histamine within serum was decreased significantly(p<0.001). 10. After premeditation of 1mg/kg of prazosin hydrochloride as ${\alpha}$$_1$-adrenergic antagonist to rabbits, the Xh was administered to them. It was found that the value of histamine within serum was decreased significantly(p<0.005). 11, Prazosin hydrochloride and yohimbine hydrochloride as ${\alpha}$$_1$-adrenergic antagonist, respectively, and ${\alpha}$$_2$-adrenergic antagonist were administerd. In this case, the value of histamine within serum was decreased significantly(p<0.0001). As the results, when the Xh is administered to various kinds of animals, the amount of histamine release within serum is increased. In view of the results so far achieved, it is concluded that Xh acted on both a$_1$-adrenoreceptor and ${\alpha}$$_2$-adrenoreceptor induces the degranulation of mast cell.

Growth and Amino Acid Contents of Spirulina platensis with Different Nitrogen Sources

  • Park, Aeran;Kim, Song-Gun;Yoon, Byung-Dae;Oh, Hee-Mock
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.6
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    • pp.368-372
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    • 2003
  • The growth and amino acid contents of the cyanobacterium, Spirulina platensis strain NIES 46, were investigated using ammonium, nitrate, nitrite, or urea as the sole nitrogen source in a batch culture. Chlorophyll a concentration was highest at 2,096$\mu\textrm{g}$/L in the nitrate group after 10days of cultivation, while the dry weight of S. platensis was highest at 4.5g/L in the ammonium group after 30days of cultivation. The total amino acid content was highest at 174mg/g dry weight of S. platensis in the urea group at the end of the cultivation period, yet the amino acid patterns for S. platensis were similar for all the experimental groups. Therefore, it seemed that the growth and amino acid composition of S. platensis varied depending on the type of nitrogen sources, while the amino acid patterns were not changed. Also, the most efficient harvesting time for S. platensis seemed to be approximately 10 days after cultivation.

Vasorelaxing Mechanism of Crude Saponin of Korea Red Ginseng in the Resistance-sized Mesenteric Artery of Rat

  • Kim, Shin-Hye;Park, Hyung-Seo;Lee, Mee-Young;Oh, Young-Sun;Kim, Se-Hoon
    • Journal of Ginseng Research
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    • v.26 no.1
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    • pp.1-5
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    • 2002
  • It has been well known that Korea red ginseng has an antihypertensive effect. The antihypertensive effect may be due to its ability to change the peripheral resistance. Change of vascular tone in the resistance-sized artery contribute to the peripheral resistance, thereby regulate the blood pressure. Therefore, we investigated to clarify the vasorelaxing mechanism induced by crude saponin of Korea red ginseng in the resistance-sized mesenteric artery of rats. The resistance-sized mesenteric artery was isolated and cut into a ring. The ring segment was immersed in HEPES-buffered solution and its isometric tension was measured using myograph force-displacement transducer. Crude saponin of ginseng relaxed the mesenmetric arterial rings precontracted with norepinephrine (3$\mu$M) in dose-dependent manner (0.01 mg/㎖ -1 mg/㎖. The relaxation by crude saponin was smaller in endothelium-intact preparation than that in endothelium-denuded preparation. The contraction induced by A23187 or phorbol 12,13-dibutyrate was not affected by crude saponin of ginseng. The vasorelaxing effect of crude saponin of ginseng was significantly attenuated by the increase of the extracellular K$\^$+/ concentration. Crude saponin-induced vasorelaxation was not affected by tetraethylammonium (1 mM), glybenclamide (10$\mu$M), and 4-aminopyridine (0.1 mM) in these preparations. Ba$\^$2+/(10$\mu$M ∼100$\mu$M) markedly reduced the crude saponin-induced vasorelakation dose-dependently. From the above results, we suggest that crude saponin of ginseng may stimulate K$\^$+/ efflux and hyperpolarize the membrane, thereby cause the vasorelaxation in the resistance-sized mesenteric artery of rats.

Acute Oral Toxicity of Extract Derived from Fruiting Body of Phellinus gilvus in Rats

  • Bae, Jae-Sung;Jang, Kwang-Ho;Park, Sung-Guk;Jo, Woo-Sik;Rhee, Man-Hee;Kwon, Oh-Deog;Kim, Young-Hoan;Kim, Eun-Young;Park, Seung-Chun
    • Toxicological Research
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    • v.19 no.3
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    • pp.211-215
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    • 2003
  • This study was carried out to investigate the acute oral toxicity of a crude extract derived from fruiting body of Phellinus gilvus (PGE) using male and female SD rats. Groups consisted of five male and female rats were treated with a single dose of the test substance intragastrically at 0, 500, 1,000, 2,000, and 5,000 mg/kgaj, respectively. Clinical signs, body weight change, and food and water consumption change were observed for 14 days after administration. No mortality or abnormal clinical signs in animals were shown during the observation period at the dose used in this study. Also there was no difference in net body weight gain, water and food consumption or gross pathological findings at terminal sacrifice among the groups of rat treated with different doses of the test substance. The results suggested that acute oral toxicity of PGE in rats is very low at the conditions employed in this study and $LD_{50}$ of PGE was estimated to be over 5,000 mg/$\textrm{m}{\ell}$ in both sexes of rats.

Leaching Behaviour of vanadium from Orimulsion ash (오리멀젼회로부터 바나듐 침출특성에 관한 연구)

  • Park Kyung-Ho;Yoon Seung-Han;Nam Chul-Woo;Choi Yeung-Ki;Yoon Oh-Seub
    • Resources Recycling
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    • v.13 no.4
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    • pp.32-38
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    • 2004
  • Recently, Orimulsion (a bitumen-in emulsion) has received increasing attention as an alternative fuel. Orimulsion combusion produces an ash rich in V, Ni and Mg which are processed to recover metals. As a basic study to recover V from Orimulsion ash, physico-chemcial properties and leaching behaviours were investigated. Orimulsion ash was fine size grains ($d_{50}$ 5.9 $\mu\textrm{m}$) with 16% V, 4 % Ni and 9% S. Vanadium was easily leached in water because Orimulsion ash was mainly constituted of metal sulfates. However, the increase of leaching temperature decreased the extraction percentage of vanadium because of hydrolysis of V(V) to vanadium pentoxide. The addition of sulfuric acid could increase the leaching percentage vanadium. In case of alkaline leaching for selective recovery of vanadium, the oxidzing agent such as $H_2$$O_2$ is required to improve the leaching per-centage