• Title/Summary/Keyword: solution pH

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Use of Biosurfactant for the Removal of Organic Pollutants in Soil/Groundwater (바이오 계면활성제에 의한 토양/지하수내 유기성 오염물질 제거)

  • Ko, Seok-Oh;Yoon, Seok-Pyo
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.2
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    • pp.193-201
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    • 2000
  • Partitioning of hydrophobic organic compounds (HOCs) to a biosurfactant, hydroxypropyl-${\beta}$-cyclodextrin (HPCD), was conducted to evaluate the feasibility of using HPCD to remove HOCs from soil/groundwater. HOC partitioning to HPCD was very fast, with over 95% of the complexation occurring within 10 min. Some influence of solution chemistry and HOC concentration on HOC-HPCD complex formation coefficients was observed. HPCD sorption on soil as quantified by both a fluorescence technique and total organic carbon measurements was negligible, indicating no significant affinity of HPCD for the solid phase. Although the HOC solubilization capability of HPCD was lower than that of synthetic surfactants such as SDS and Tween 80, HPCD can be effective in removing sorbed HOCs from a model subsurface environment, primarily because of its negligible sorption to the solid phase (i.e., all the HPCD added facilitates HOC elution). However, in contrast with conventional surfactants, HPCD becomes relatively less effective for HOC partitioning with increasing HOC size and hydrophobicity. Therefore, comparisons between HPCD and synthetic surfactants for enhanced remediation applications must consider the specific HOC(s) present and the potential for surfactant material losses to the solid phase, as well as other more generally recognized considerations such as material costs and potential toxicological effects.

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A Study of Interference Factor of Analysis Method of Hexavalent Chromium in Soil using UV/VIS Spectrometry and Application of Ion Chromatography (자외선/가시선 분광법을 이용한 토양 중 6가 크롬 분석방법의 방해요인 분석 및 이온크로마토그래피 적용에 관한 연구)

  • Noh, Hoe-Jung;Lee, Myung-Gyu;Lee, Hyeon Seok;Kim, Mira;Kim, Dongho;Kim, Tae Seung
    • Journal of Soil and Groundwater Environment
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    • v.17 no.6
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    • pp.33-42
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    • 2012
  • This study was performed to find the problems according to interference factors (organic matter, pH, Cr, Mn, Fe, clay, and etc.) when we analyzed the hexavalent chromium [Cr(VI)] in soils using UV/VIS spectrometer (US EPA 7196A), attempted to evaluate the domestic applicability of analytical method (US EPA 7199) using IC-UV/VIS spectrometer as alternative method. The recovery rate of certified reference materials was 75.0% (US EPA 7196A) and 101.4% (US EPA 7199) by the analytical methods. As the results of performing QA/QC about US EPA 7199, method detection limit (MDL) and limit of quantification (LOQ) were 0.062 mg/kg, 0.196 mg/kg, respectively. The LOQ of US EPA 7199 was lower than that of the current soil official testing method in Korea (0.5 mg/kg). Cr(VI) contents in 23 soil samples were compared by the analytical methods of EPA 7196A and 7199. Cr(VI) was detected in 13 of 23 soil samples by EPA 7196A, while EPA 7199 was not detected in any soil samples. The Cr(VI) content in 23 soil samples by EPA 7196A was not clearly correlated with Cr, Fe, Mn and clay content in the soil samples. However, the contents of Cr(VI) and organic matter of the soil samples had the highest coefficient of determination ($R^2$) of 0.80. In order to evaluate the correlation between the recovery rates of Cr(VI) and organic matter contents in the soil samples, the recovery rates of 5 soil samples added Cr(VI) standard solution were analyzed by the analytical methods. According to the results, the higher the organic matter contents in soil samples, the lower the recovery rates of Cr(VI) by US EPA 7196, while in case of US EPA 7199, the recovery rates were stable regardless of the organic matter contents.

Comparison of apical extrusion of intracanal bacteria by various glide-path establishing systems: an in vitro study

  • Dagna, Alberto;El Abed, Rashid;Hussain, Sameeha;Abu-Tahun, Ibrahim H;Visai, Livia;Bertoglio, Federico;Bosco, Floriana;Beltrami, Riccardo;Poggio, Claudio;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • v.42 no.4
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    • pp.316-323
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    • 2017
  • Objectives: This study compared the amount of apically extruded bacteria during the glide-path preparation by using multi-file and single-file glide-path establishing nickel-titanium (NiTi) rotary systems. Materials and Methods: Sixty mandibular first molar teeth were used to prepare the test apparatus. They were decoronated, blocked into glass vials, sterilized in ethylene oxide gas, infected with a pure culture of Enterococcus faecalis, randomly assigned to 5 experimental groups, and then prepared using manual stainless-steel files (group KF) and glide-path establishing NiTi rotary files (group PF with PathFiles, group GF with G-Files, group PG with ProGlider, and group OG with One G). At the end of canal preparation, 0.01 mL NaCl solution was taken from the experimental vials. The suspension was plated on brain heart infusion agar and colonies of bacteria were counted, and the results were given as number of colony-forming units (CFU). Results: The manual instrumentation technique tested in group KF extruded the highest number of bacteria compared to the other 4 groups (p < 0.05). The 4 groups using rotary glide-path establishing instruments extruded similar amounts of bacteria. Conclusions: All glide-path establishment instrument systems tested caused a measurable apical extrusion of bacteria. The manual glide-path preparation showed the highest number of bacteria extruded compared to the other NiTi glide-path establishing instruments.

Isolation and Partial Characterization of Isoflavone Transforming Lactobacillus plantarum YS712 for Potential Probiotic Use (Isoflavone 비배당화 및 항산화 활성을 지닌 Lactobacillus plantarum YS712의 선발)

  • Cho, Yoon-Hee;Imm, Jee-Young;Kim, Hwa-Young;Hong, Seong-Gil;Hwang, Sung-Joo;Park, Dong-Jun;Oh, Se-Jong
    • Food Science of Animal Resources
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    • v.29 no.5
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    • pp.640-646
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    • 2009
  • Lactic acid bacteria (LAB) are typical probiotic microbes that are used in various industries including fermented foods, feed additives, and pharmaceuticals. The purpose of this study was to compare the ability of isoflavone biotransformation and antioxidative activity of 17 LAB. Six strains including the Lactobacillus species exhibited a 100% hydrolysis rate for daidzein during fermentation. The content of total genistein in soymilk fermented with these strains was $872-943\;{\mu}g/g$. The DPPH (1, 1-diphenyl-2-picrylhydrazyl) radical scavenging ability of the LAB was widely variable and ranged from 23-78%. A selected strain was isolated from kimchi and the strain was identified as Lactobacillus plantarum ssp. through the API carbohydrate fermentation pattern and 16S rDNA profile. The strain exhibited excellent acid tolerance in an artificial gastric solution. L. plantarum YS712 showed high $\beta$-glucosidase activity in fermentation. The concentration of genistein and daidzein in soymilk fermented with L. plantarum YS712 increased from 3.64 to $917.3\;{\mu}g/g$ and from 58.18 to $1062.17\;{\mu}g/g$, respectively. These results demonstrate the potential of L. plantarum YS712 as a probiotic culture that can be utilized in the manufacturing of fermentation foods and dietary supplements.

Study on the Single Dose Toxicity of ShinEumHur Pharmacopuncture Injected into the Muscles of Rats

  • Jeong, Hohyun;Cha, Eunhye;Lee, Jongcheol;Lee, Seongjin;Park, Manyong;Kim, Dongwoung;Song, Bongkeun;Lee, Jongdeok;Kim, Sungchul
    • Journal of Pharmacopuncture
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    • v.19 no.4
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    • pp.350-358
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    • 2016
  • Objectives: This study was carried out to analyze the single dose toxicity of ShinEumHur (SEH) pharmacopuncture injected into the muscles of Sprague-Dawley rats. Methods: The SEH pharmacopuncture was made in a clean room at the Korean Pharmacopuncture Institute (K-GMP). After the mixing process with sterile distilled water had been completed, the pH was controlled to between 7.0 and 7.5. All experiments were conducted at Biotoxtech, an institution authorized to perform non-clinical studies under the Good Laboratory Practice (GLP) regulations. Sprague-Dawley rats were chosen for the pilot study. Doses of SEH pharmacopuncture, 0.25, 0.5 and 1.0 mL, were administered to the experimental groups, and a dose of normal saline solution, 1.0 mL, was administered to the control group. We examined the survival rate, weights, clinical signs, mean hematology parameters, mean clinical chemistry, necropsy and histopathological findings. This study was conducted under the approval of the Institutional Animal Ethics Committee. Results: No deaths or abnormalities occurred in any of the four groups. No significant changes in weight, hematological parameters or clinical chemistry between the control group and the experimental groups were observed. To check for abnormalities in organs and tissues, we used microscopy to examine representative histological sections of each specified organ; the results showed no significant differences in any of the organs or tissues. Conclusion: The above findings suggest that treatment with SEH pharmacopuncture is relatively safe. Further studies on this subject are needed to yield more concrete evidence.

Mechanism of Relaxation of Rat Aorta by Scopoletin; an Active Constituent of Artemisia Capillaris

  • Kwon Eui Kwang;Jin Sang Sik;oChoi Min H;Hwang Kyung Taek;Shim Jin Chan;Hwang Il Taek;Han Jong Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.2
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    • pp.389-396
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    • 2002
  • In the present work, we examined the mechanism of vasorelaxant effect of scopoletin, an active constituent of Artemisia capillaris on rat thoracic descending aortic rings. Scopoletin induced a concentration-dependent relaxation in rat thoracic descending aortic rings pre-contracted with phenylephrine (EC/sub 50/ = 238.94±37.4 μM), while it was less effective in rat thoracic descending aortic rings precontracted with high potassium solution (KCI 30 mM). Vasorelaxation by scopoletin was significantly inhibited after endothelial removal, but recovered at high concentration. Pretreatment of rat thoracic descending aortic rings with N/sup G/-nitro-L-arginine (100 μM), a nitric oxide synthase inhibitor, and atropine (1 μM), a muscarinic receptor antagonist, significantly inhibited scopoletin-induced relaxation of rat thoracic descending aortic rings. Neither indomethacin (3 μM), an inhibitor of cydooxygenase, nor propranolol (1 μM), a β -adrenoceptor antagonist, modified the effect of scopoletin. The combination of N/sup G/ -nitro-L-arginine (100 μ M) and miconazole (10 μ M), an inhibitor of cytochrome P 450, did not modify the effect of scopoletin, when compared with pretreatment with N/sup G/-nitro-L-arginine(100 μM) alone. Vasorelaxant effect of scopoletin was inverted by pretreatment with diltiazem (10 μM), a Ca/sup 2+/-channel blocker, at low concentration, while restored at high concentration. Apamin (K/sub ca/-channel blocker, 1 μM), 4-aminopyridine (4-AP, K/sub v/-channel blocker, 1 mM), and tetrodotoxin (TTX, Na/sup +/-channel blocker 1 μM) potentiated the vasorelaxant effect of scopoledn, but glibendamide (K/sub ATP/-channel blocker, 10 μM), tetraetylammonium(TEA, non-selective K-channel blocker, 10 mM) did not affect the relaxation of scopoletin. Free radical scavengers (TEMPO, catalase, mannitol) did not modify vascular tone. These results suggest that nitric oxide, Ca/sup 2+/ -channels play a role in endothelium-dependent relaxations to scopoletin in rat aortas, that apamin, 4-AP, TTX but not glibenclamide, TEA potentiated relaxation to scopoletin mediated by these channels, and that free radicals do not concern to the vasorelaxant effect of scopoletin.

Studies on the promoted Aging of flue-cured leaf tobacco by cellulolytic Enzyme and Nicotinophiles (섬유소 분해효소 및 니코틴 분해세균을 이용한 잎담배의 발효촉진효과)

  • 이태호;성낙계
    • Journal of the Korean Society of Tobacco Science
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    • v.13 no.2
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    • pp.5-20
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    • 1991
  • For the quality enhancement of harvested-year leaf tobacco to the quality of 2-year naturally aged leaf tobacco, cellulose and nicotine degradative bacteria were isolated and identified. Effects of artificial fermentation treated cellulase and nicotine degradative bacteria on the quality of leaf tobacco were investigated from the chemical and sensory points of view. 1, Changes in chemical composition of leaf tobacco resulted from the addition of cellulase extracted from Cellulomonas sp. [3ml(${\mu}{\textrm}{m}$ D-glucose/ml. mil-1) of enzymes solution 11009 of leaf tobacco] and nicotine degradative bacteria, Pseudomonas sp. 2ml(IX109 cells$\div$ 100g of leaf tobacco), and subsequently fermented at 40${\mu}{\textrm}{m}$$^{\circ}C$, 65% R. H. for 40 days are as follows : 1) Content of crude fiber decreased 12% It took 9 min, 53 sec. to reach full combustion in control group but took only 7 min. 47 sec. in the treated group, taking almost equal time to 2-year naturally aged leaf tobacco(7 min. 35sec.). 2) Light intensity of control group was 60.96% with bright lemon color but that of treated leaf tobacco accounted for 47.69 with orange to dark brown color series, which was almost equal to the value, 45.69, of 2-year naturally aged leaf tobacco. 3) Linoleic acid, serving mild taste among organic acids, amounted to 1.llmg/g in control group but increased to 1.35m9/9 in the treated leaf tobacco, identical to the content(1.35mg/g) of 2-year naturally aged leaf tobacco. 4) Content of solanone, on of the typical leaf tobacco flavor compounds, accounted for 2.95% in control group but increased to 2.87% in treated group. 5) Methyl furan, useful flavor compound in smoke composition, accounted for 17.6$\mu\textrm{g}$/cig. in control group but increased to 25.9$\mu\textrm{g}$/cig. in treated group. However, acroleine decreased from 69.3$\mu\textrm{g}$/cig. in control group to 58.6$\mu\textrm{g}$/cig. in treated group 2. In sonsory test, mild taste evaluation of control group scored 5.47 and treated group 7.93 which was evaluted almost equal to the value(8.00) of 2-year naturally aged leaf tobacco. Aroma evaluation of control group scored 5.60, treated group 8.20, and 2-year naturally aged leaf tobacco 8.33. In addition, total harmony taste of control group showed 5.67, treated group 8.07 (p<0.01), and 2-year naturally aged leaf tobacco 8.00. From these results, it can be said that quality of treated leaf tobacco is not inferior to that 2-year naturally aged leaf tobacco.

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Effects of Propofol and Remifentanil Combination Anesthesia on Intraocular Pressure and Hemodynamic Parameters in Dogs (개에서 Propofol/Remifentanil 병용마취 후 안압 및 혈역학 변화)

  • Lim, Tae-Sun;Yun, Sung-Ho;Park, Ji-Hee;Kwon, Young-Sam;Jang, Kwang-Ho
    • Journal of Veterinary Clinics
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    • v.29 no.6
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    • pp.447-454
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    • 2012
  • The objective of this study was to determine the effect of propofol and remifentanil combination on hemodynamics and intraocular pressure (IOP), and to compare with those of isoflurane in beagle dogs. Fourteen clinically healthy beagle dogs were divided randomly into 2 groups and each group was consisted with 7 dogs. Anesthetic agents were propofol (0.2 mg/kg/min) plus remifentanil ($0.5{\mu}g/kg/min$, 1% solution in standard saline) in one group (group PRP) and 3% isoflurane in the other group (group ISF). Anesthesia was maintained for 90 min in the both groups. IOP, blood pressure, heart rate and blood gas values (pH, $PaCO_2$, $PaO_2$, $SaO_2$, $tCO_2$, ${HCO_3}^-$) were recorded at 5, 10, 15, 30, 45, 60, 75 and 90 min in the both groups. IOP values in both eyes were significantly decreased in group PRP compared with those in group ISF. but there were no significant differences between two eyes in each group. Systolic, diastolic and mean blood pressures were significantly decreased in group PRP within the normal range. There were no differences between groups in all blood gas parameters. In this study, propofol and remifentanil combination could provide stable IOP and blood pressure compared with isoflurane.

Bioequivalence of Erblon Capsule to Erdos Capsule (Erdosteine 300 mg) (엘도스 캡슐(에르도스테인 300 mg)에 대한 엘브론 캡슐의 생물학적 동등성)

  • Cho, Hea-Young;Lee, Suk;Kang, Hyun-Ah;Moon, Jai-Dong;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.33 no.3
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    • pp.237-243
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    • 2003
  • Erdosteine, the thiol derivatives chemically related to cysteine, is a mucolytic and mucoregulator agent which modulates mucus production and viscosity and increases mucociliary transport. The purpose of the present study was to evaluate the bioequivalence of two erdosteine capsules, Erdos (Dae Woong Pharmaceutical Co., Korea) and Erblon (Kuhn Il Pharmaceutical Co., Korea), according to the guidelines of Korea Food and Drug Administration (KFDA). The erdosteine release from the two erdosteine capsules in vitro was tested using KP VII Apparatus II method with various different kinds of dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty four healthy male subjects, $23.33{\pm}2.06$ years in age and $66.18{\pm}8.19\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After three capsules containing 300 mg as erdosteine were orally administered, blood was taken at predetermined time intervals and the concentations of erdosteine in serum were determined using HPLC method with UV detector. The dissolution profiles of two formulations were similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t,\;C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t\;and\;C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the Erdos were 0.20%, 1.10% and -9.44% for $AUC_t,\;C_{max}\;and\;T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) $(e.g.,\;log(0.94){\sim}log(1.22)\;and\;log(0.92){\sim}log(1.20)\;for\;AUC_t\;and\;C_{max},\;respectively$. Thus, the criteria of the KFDA guidelines for the bioequivalence was satisfied, indicating Erblon capsule and Erdos capsule are bioequivalent.

Preparation and Keeping Quality of Canned Liquid Smoked Oyster Products (훈액처리에 의한 굴 통조림의 품질개선에 관한 연구)

  • LEE Eung-Ho;CHO Soon-Yeong;CHUNG Su-Yeol;CHA Yong-Jun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.1
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    • pp.1-7
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    • 1983
  • In order to improve the quality of canned oyster, canned oyster in oil as control, canned smoked oyster in oil and canned liquid smoked oyster in oil were prepared, and the masking effect of green meat and the stability of their qualities during storage were examined. Three kinds of canned oyster products showed little change in pH, VBN and TBA during 4 months storage in room temperature. In texture of the products, however, hardness and toughness of all the products decreased slightly after 3 months storage, while elasticity and cohesiveness did not change largely up to 4 months storage. Green meat appeared on the surface of canned oyster in oil as control after 30 days storage. And the masking of green meat could be achieved more effectively by dipping treatment of meat for 30 seconds in smoke flavor(Smoke-EZ, Alpha Foods Co., Ltd.) solution than conventional smoking process.

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