• Title/Summary/Keyword: acidic pH

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Heavy Metal Concentrations in the Soil of Yoecheon Industrialized Complex Area (여천공단 주변 토양의 중금속함량에 관한 연구)

  • 윤연흠;박돈희;김용웅;조완현;박천영;윤정한
    • Economic and Environmental Geology
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    • v.33 no.5
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    • pp.379-389
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    • 2000
  • This study was focused on the investigation for the heavy metal contamination of soils derived from Yoecheon Industrial Complex in Chonnam Province. Total 201 soil samples including farmland, paddy, forest and playground soils were collected, extracted by 0.1N HCl and analyzed for Cd, Cu, Cr, Fe, Mn and Zn using AAS. Most pH values in soils were weak acidic ranges of 4-6, while some of them were over 8.0. Concentrations of Cd, Cu, Fe and Zn in the soils tend to be relatively high around the Au-Ag mine area, railroad stations and oil station, however, those of Cr, Mn and Pb show high at the northside of Pohang Steel Co (POSCO). Cadmium-Zn couples, and Cd-Zn and Zn-Cr couples have relatively good correlations in the farmland soils and paddy soils, respectively. Concentrations of Cd, Fe and Zn with depth tend to be higher in the top soils than in the bottom soils, but those of Cu and Pb do not show regular variations with depth.

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Studies on the Development of a Microbial Cryoprotectant Formulation Using a W/O/W Multiple Emulsion System

  • Bae, Eun-Kyung;Cho, Young-Hee;Park, Ji-Yong
    • Journal of Microbiology and Biotechnology
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    • v.14 no.4
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    • pp.673-679
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    • 2004
  • A microbial cryoprotectant formulation using a W/O/W multiple emulsion system was developed. The psychrotolerant microorganism, B4, isolated from soil in South Korea, was observed by the drop freezing method, in which the microorganism sample inhibited ice nucleation activity. The antifreeze activity was eliminated when the microorganism sample was treated with protease, indicating that the antifreeze activity was due to the presence of antifreeze protein. The result of the l6S rDNA sequencing indicated the B4 strain was most closely related to a species of the genus Bacillus. Culture broth of B4 strain (Bacillus sp.) and rapeseed oil containing 1 % polyglycerine polyricinolate (PGPR) were used as core and wall material, respectively. The most stable W/O emulsion was prepared at a core/oil ratio of 1:2. The highest W/O/W emulsion stability was achieved when the primary emulsion to external aqueous phase containing 0.5% caster oil polyoxyethylene ether $(COG25^{TM})$ ratio was 1:1. Microcrystalline cellulose showed better W/O/W emulsion stability than other polymer types. The viability of cells in a W/O/W emulsion was higher than free cells during storage at $37^\circ{C}$. An acidic pH and UV exposure decreased the viability of free cells, but cells in W/O/W emulsion were more stable under these conditions.

Purification of Cephalosporin C Produced by Cephalosporium acrernoniurn (Cephalosporium acremonium 변이주가 생성하는 Cephalosporin C의 정제)

  • 이헌주;손영선;안동호;김현수;현형환
    • Microbiology and Biotechnology Letters
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    • v.20 no.2
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    • pp.178-182
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    • 1992
  • For an industrial-scale purification and production of cephalosporin C from a culture broth of Ceplzalos#mium nmemonium CSA-2.8A3 mutant, ultrafiltration, column chromatography, reverse osmosis, and spray drying were empolyed. Above 90% of yield and high purity of cephalosporin C were obtained through WA-30, HP-20, XAD-2000 and SK-1B column chromatographies. Especially, in the tendom operation of the columns, the recovery yield was increased up to 96%. The purified cephalosporin C was stable at $4^{\circ}C$ and in acidic condition, while it was unstable at room temperature and in alkaline condition at pH above 8.0. Cephalosporin C powder or a final product prepared by spray drying contained 85.554 of sodium cephalosporin C, 6.3%' of water, 4.63% of free $Na^+$ ions. and traces of metal ions.

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Studies on Environmental Impact of Pulp and Addtives in Liner Papermaking

  • Seo, Jin-Ho;Kim, Hyoung-Jin
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2006.06b
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    • pp.441-444
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    • 2006
  • A lot of water is using in the paper mill for dilution, washing, sealing, and other process operation. As the regulation of water environment has been more tightened than ever before, water management in the paper mill becomes the most important task. Topics on reducing fresh water and increasing recycling water have been studied. Further, an interest in zero-effluent system has been increased. The pH of waste water in paper mill is usually weak acidic or neutral. The waste water in the paper mill includes water insoluble organic materials that are not easy to be dissolved in the water, inorganic materials that never react with water and chemical additives that are used to recycled fiber. This study investigated on the effect of various materials used in paper mill on COD. This data could be used to control the environmental load in paper mill. COD caused by raw materials and NBDCOD (Non Bio Degradable COD) after the activated sludge process are investigated in this study. Results obtained in this study can be used in a simulation program designed to control environmental load in the paper mill.

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The Study of Cochineal Dyeing. (코치닐의 염색성에 관한 연구)

  • 주영주;소황옥
    • Textile Coloration and Finishing
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    • v.10 no.1
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    • pp.11-19
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    • 1998
  • For the purpose of standardization and practicability of dyeing by natural dyes, the mordanting and dyeing properties of cochineal and carminic acid were studied. Appropriate extraction, dyeing and mordanting condition of cochineal were determined, and the effect of mordanting method on dye uptake and color fastness of dyed fabric was investigated. The maximum absorbance of cochineal solution was 495nm, carminic acid was 533nm and 577nm. The color of carminic acid solution was affected by pH 6~9. The optimum temperature to extract cochineal was $80-100^\circ{C}$ and dyeing solution for 1 hour. And effective dyeing time to silk was 60min. Effective mordanting temperature was $80^\circ{C}$, and its time was 30min. In case mordants concentration, the maximum absorbance of Sn solution was 3%, K, Cu and Cr were in 1%. K/S value of dyeing fabrics was recoginazed by mordant treatment, specially Fe, Sn, Al, Cu. In the case of cochineal light fastness was increased by mordant treatment, specially Fe treatment. Perspiration fastness was good in acidic solution than in alkaline solution and perspiration fastness of cochineal was poor. Fastness of abrasion and dry-cleaning were good and these fastness improvement were generally effective for post-mordanting treatment.

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Microflora Occurring in the Fermentation by Tea Fungus (Tea fungus 발효음료 제조시 발효계의 미생물상)

  • 최미애;최경호;김정옥
    • Journal of Life Science
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    • v.6 no.1
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    • pp.56-65
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    • 1996
  • Black tea extractbsupplemented with 10% sucrose was fermented by fungus at 30$\circ$C. A pellicle thick as 7$\sim$8 mm covered entire surface of the medium and the wxtract converted to acidic beverage(abbreviated below as fermented black tea) by 14 days of fermentation. It was a kind of acetic acid fermentation depending on symbiotic microorganisms. During the fermentation strains of yeasts(Saccharomyces cerevisiae and Eeniella sp.)and bacteria(Bacillus subtilis, Kurthia zopfii, Gluconobacter oxydans and Deinicoccus sp.) were isolated from aqueous layer. Contrastly to it, a bacterial strain(Acetobacter aceti) was isolated from thick pellicle. The bacteria grew as a viscouse cluster on solid agar medium differently from usual strains of A. aceti. Fermented black tea had sweet-sour taste and sweet smell.

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Biochemical Changes of Protein during the Senescence of Tobacco Leaf (담배잎의 노화과정에 따른 단백질의 생화학적 변화)

  • 이상각;심상인;강병화
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.5
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    • pp.563-568
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    • 1996
  • This experiment was conducted to obtain basic information of biochemical changes in the process of senescence by measuring the total RNA, protein, protease activity and electrophoretic pattern of protein in tobacco plant. The content of soluble protein increased by 15 days after leaf emergence and its level was not changed from 15 to 35 days after leaf emergence. The content of total RNA showed a maximum value at 15 days after leaf emergence and then decreased rapidly until 30 days after leaf emergence. The activity of protease of neutral fraction was higher than that of acidic fraction and rapidly increased up to the end of senescence after 50 days after leaf emergence. According to the analysis of electrophoresis, polypeptide band of 61kd was developed after 35 days after leaf emergence and increased by the end of senescence.

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Contamination of Heavy Metals in Stream Sediments in the Vicinity of the Sambo Pb-Zn-Barite Mine (삼보 연-아연-중정석 광산 주변 하상퇴적물에서의 중금속 오염 연구)

  • Kim, Sang-Hyun;Chon, Hyo-Taek
    • Economic and Environmental Geology
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    • v.26 no.2
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    • pp.217-226
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    • 1993
  • Stream sediment samples were collected in the vicinity of the Sambo Pb-Zn-barite mine in order to investigate dispersion patterns and pollution levels of heavy metals, and to find out their mode of occurrences. Those samples were analyzed for Cd, Cu, Pb, Zn, Fe, and Mn by using partial extraction and sequential extraction methods. Stream sediments of this studied area has been contaminated severely by Pb, Zn, and Cd. Dispersion patterns of heavy metals in those sediments are different according to their pollution source and sampling distance from the mine. The stream sediment pH is generally neutral in control area, and is slightly acidic in the lower part of tailing dam. The main pollution source of stream sediments was confirmed as tailing and mine drainage. Their pollution level depends mainly on inflowed water and distance from the mine. The tolerance index ranges from -0.9 to 0.7. The mode of occurrances of heavy metals in polluted stream sediment are identified as Fe-Mn oxides, organic bounded and carbonate-bounded compound which show high potential of bioavailablity.

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Swelling of Commercial Matrix Tablets Based on Carboxymethyl Cellulose Sodium and Alginic Acid (시판중인 메트릭스 정제의 팽윤력 비교 연구)

  • Kim, Ki Taek;Kim, Ji Su;Park, Ju-Hwan;Lee, Jae-Young;Jo, Yeong Woo;Yang, Jae-Gwon;Jang, Jun Hee;Choi, Eun-Sun;Kim, Dae-Duk
    • YAKHAK HOEJI
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    • v.60 no.2
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    • pp.73-77
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    • 2016
  • Alginic acid and carboxymethyl cellulose sodium are dietary fibers from plants. They have a swelling property and delay the gastric emptying time, thereby resulting in feeling satiated after oral administration, which may eventually contribute to loss of body weight. The goal of this study was to compare swelling property of three commercial matrix tablets based on alginic acid and carboxymethyl cellulose sodium. When the swelling was determined by the Korean Ministry of Food and Drug Safety (MFDS) guideline, the tablet prepared by direct compression method with highly viscous swelling agent showed the highest swelling in acidic conditions. Water uptake of these tablets was rapid and completed within 30 min. Moreover, when the pH was changed from 2.5 to 6.8 buffer, the water uptake was not significantly changed in all tablets.

Quality and antioxidant activity of ginseng seed processed by fermentation strains

  • Lee, Myung-Hee;Lee, Young-Chul;Kim, Sung-Soo;Hong, Hee-Do;Kim, Kyung-Tack
    • Journal of Ginseng Research
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    • v.39 no.2
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    • pp.178-182
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    • 2015
  • Background: Fermentation technology is widely used to alter the effective components of ginseng. This study was carried out to analyze the characteristics and antioxidant activity of ginseng seeds fermented by Bacillus, Lactobacillus, and Pediococcus strains. Methods: For ginseng seed fermentation, 1% of each strainwas inoculated on sterilized ginseng seeds and then incubated at $30^{\circ}C$ for 24 h in an incubator. Results: The total sugar content, acidic polysaccharides, and phenolic compounds, including p-coumaric acid, were higher in extracts of fermented ginseng seeds compared to a nonfermented control, and highest in extracts fermented with B. subtilis KFRI 1127. Fermentation led to higher antioxidant activity. The 2,2'-azine-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity was higher in ginseng seeds fermented by Bacillus subtilis than by Lactobacillus and Pediococcus, but Superoxide dismutase (SOD) enzyme activity was higher in ginseng seeds fermented by Lactobacillus and Pediococcus. Conclusion: Antioxidant activities measured by ABTS and SOD were higher in fermented ginseng seeds compared to nonfermented ginseng seeds. These results may contribute to improving the antioxidant activity and quality of ginseng subjected to fermentation treatments.