• Title/Summary/Keyword: Acid and Alkali

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Groundwater Contamination by Cation, Anion and Pesticides (지하수중 음이온, 양이온, 및 금속의 함량)

  • 김형석;정세영;최중명
    • Journal of environmental and Sanitary engineering
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    • v.7 no.2
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    • pp.111-128
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    • 1992
  • According to the increase of population and industrialization, the quality of our drinking water are becoming worse by the contamination of resources, production of THM and other halogenated hydrocarbons during the purifying process, the problem of corroded water supplying pipeline, and the water reservoir tanks, Many people choose groundwater to drink instead of city tap water, but sometimes we get report about groundwater contamination by wastes, swage, septic tank, etc. It is reported that in U. S. over 20% of population are drinking groundwater, but U. S EPA reported the groundwater contamination by pesticides, herbicides, fungicides, fertilizer, and various chemical substances. Craun, et at announced the groundwater contamination by bacteria which are related with poor installation of septic tank. Johnson and Kross mentioned aboutmethemoglobinemia by NO3-N originated from human and animal feces, organic chemicals, and fertilizer, and as the results the infant mortality could be risen. Some scientist also reported the high concentration of metals in groundwaters and some cation and anions, and volatile organic compou nds. Authors investigated 80 groundwaters in urban, agricultural, and industrial area during last 3 month(June - August) to check any drinking water quality parameters are exceeding the standards. The results were as follow. 1, The average value of ammonia nitrate were within the standard, but 11.76% of urban area were exceeded the 10 rpm standard, in agricultural area 42.3175 were exceeded, and in industrial area 20.2% were exceeded the drinking water standard of 10 ppm. the highest concentration was 29.37 ppd in industrial area. 2. The mean value of metals is not exceeded the standard, but there were some groundwater whose Mn value was 0.424 ppm(standard is 0,3 ppm) in urban area, 0.737 rpm in agricultural area, and 5.188 ppm in industrial area. The highest Zn value was 1.221 ppm (standard is 1.0 ppm)was found in industrial area. 3. The percentage of contamination by general bacteria was 8.82% in urban area, 15.38% in agricultural area, and 15.00% in industrial area. Escherichia coil group was also contaminated by 35.29% in urban area, 30.76% in agricultural area, and 30.00% in industrial area. 4, The pH value was within the standard which means there was no influence by acid or alkali chemicals, nor acid rain Through the above results, all the groundwater should be tested to check the safety for drinking water and should make some alternative methods suitable for drink.

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Gelatinization and Retrogradation Properties of Surfactant Added Sweet Potato Starches (계면활성제 첨가 고구마 전분의 호화와 노화특성)

  • Lee, Shin-Kyung;Shin, Mal-Shick
    • Applied Biological Chemistry
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    • v.37 no.6
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    • pp.463-471
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    • 1994
  • Physicochemical properties, gelatinization and retrogradation characteristics of surfactant added sweet potato starches were investigated. Three different surfactants, SSL (sodium stearoyl-2-lactylate), Dimodan (mono/diglyceride) and SE1670 (sucrose fatty acid ester 1670) were used. Shapes and crystallinities of starch granules were not changed by the addition of surfactants. Total lipid contents increased and the amylose content decreased by the addition of surfactants and the order was as follows: SE1670>SSL>Dimodan. The swelling power and solubility at $80^{\circ}C$ decreased in the surfactant added starches. By amylograph, initial gelatinization temperature of untreated sweet potato starch was $72.5^{\circ}C$, and did not change by the addition of surfactants, but SE1670 or Dimodan added starch showed the peak viscosity. The peak temperature of gelatinization and enthalpy of untreated starch by DSC were $53.9^{\circ}C$ and 1.3cal/g, respectively. The peak temperature increased by the addition of surfactants, while the enthalpy decreased. In gelatinization by alkali, the viscosity was lower in surfactant added starches than in untreated starch at concentration. The degree of retrogradation by ${\alpha}-amylase-iodine$ method was a lower in SSL and SE1670 added starches than untreated starch and the enthalpy by DSC also decreased in surfactant added and retrograded starches.

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Component Analysis and Antioxidant Activity of Pueraria flos (갈화(葛花)의 함유성분 분석과 항산화 활성)

  • Shin, Eon-Hwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.9
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    • pp.1139-1144
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    • 2009
  • The purpose of this study is to determine the possibility of using Pueraria flos as natural health food source. To accomplish this purpose, the contents of general and antioxidative nutrients of Pueraria flos a were measured. The contents of carbohydrate, crude protein, crude lipid and ash were 69.2%, 19.9%, 2.2% and 8.9%, respectively, and calories was 340.4 kcal. Total dietary fiber was 85.1% of total carbohydrates. The percentages of water soluble dietary fiber to insoluble dietary fiber were 12.0% and 46.7%, respectively. The protein contained 18 different kinds of amino acids. The contents of essential and non-essential amino acids were 5.0 g and 6.7 g. The Ca was the largest mineral followed by K, Mg, and P, which means Pueraria flos is alkali material. The contents of saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids were 25.37%, 33.61% and 35.68%, respectively. Therefore, the amount of the total unsaturated fatty acid was higher than that of any other plant. The antioxidant activity of 70% ethanol extract and fractions of the Pueraria flos has been determined by the scavenging of the stable radical DPPH; the result showed that the ethyl acetate fraction was the most active, as the amount required for 50% reduction of DPPH after 30 mins ($RC_{50}$) was 109.9 ${\mu}g$, followed by 70% ethanol extract (217.3 ${\mu}g$), hexane fraction (134.5 ${\mu}g$), chloroform (116.7 ${\mu}g$), butanol faction (129.8 ${\mu}g$) and aqueous fraction (473.5 ${\mu}g$).

Chemical Composition and Biological Activities of Immunostimulants Purified from Alkali Extract of Poria cocos Sclerotium (복령 균핵의 알칼리추출물에서 정제한 면역활성 증강물질의 작용과 화학구성)

  • Rhee, Sang-Dal;Cho, Soo-Muk;Park, Jeong-Sik;Han, Sang-Bae;Jeon, Young-Jin;Kim, Hwan-Mook;Kim, Gwang-Po
    • The Korean Journal of Mycology
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    • v.27 no.4 s.91
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    • pp.293-298
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    • 1999
  • An one percent sodium carbonate extract prepared from sclerotia of Poria cocos activated the proliferation of the T lymphocytes as measured by mixed lymphocyte responses(MLR). The active fraction, PCSC22, was isolated from an one percent sodium carbonate extract by a combination of fractionation procedures, including ethanol precipitation and chromatographies on column of DEAE-cellulose and Sephadex G50. Carbohydrate and peptide contained in PCSC22 were 78 : 22% in ratio. On employing gel filtration high performance liquid chromatography, PCSC22 exhitited a homogeneous peak with an average molecular weight of 8 kDa. The sugar moiety of PCSC22 was composed with mannose (92%), galactose (6.2%) and arabinose (1.3%), which might be indicated as heteromannan. Fifteen amino acids were found in peptide moiety of the polysaccharide and aspartic acid, serine, and valine were major components. PCSC22 activated the primary proliferation of T lymphocytes measured by mixed lymphocyte responses, the antibody production of the B lymphocytes and the secretion of nitric oxide from macrophage cell line, RAW264.7.

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Antimicrobial Activity of Korean Wild Tea Extract According to the Degree of Fermentation (발효정도에 따른 국내산 야생차 추출물의 항균활성)

  • Choi, Ok-Ja;Rhee, Haeng-Jae;Choi, Kyeong-Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.2
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    • pp.148-157
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    • 2005
  • This study was investigated to determine antimicrobial activity of the water and ethanol extracts of Korean wild green tea, semi-fermented tea, and fermented tea. Antimicrobial activity was examined against 8 kinds of several microorganisms. The minimum inhibitory concentration (MIC) of the water and ethanol extracts of green tea showed the most active antimicrobial activity against B. subtilis 0.2 mg/mL in Gram positive bacteria and P. fluorescens 0.3∼0.5 mg/mL in Gram negative bacteria. But the extracts did not show antimicrobial activity against lactic acid bacteria and yeast at the level of less than 1 mg/mL. Antimicrobial activity got lower as tea got more fermented. Antimicrobial activity of ethanol extracts from green tea, semifermented tea, and fermented tea was stronger than that of water extracts. Antimicrobial activity of the water and ethanol extracts of green tea, semi-fermented tea, and fermented tea was not destroyed at 50∼121$^{\circ}C$, and pH 3∼11, which proved to be very stable when given over heat, acid & alkali treatment. The ethanol extract of green tea, semi-fermented tea, and fermented tea was fractionated in the order of hexane, diethyl ether, ethyl acetate and water fraction. The highest antimicrobial activity was found in the water fraction, but not found in hexane fraction, while antimicrobial activity of fermented tea was not found in ether fraction.

Geochemical Experiment for Effective Treatment of Abandoned Mine Wastes (광산폐석의 효과적 처리를 위한 지화학적 연구)

  • 이진국;이재영
    • Journal of Korea Soil Environment Society
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    • v.3 no.1
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    • pp.31-44
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    • 1998
  • The geochemical experiments were carried out to investigate a removal effect of heavy metals in abdndoned metallic mine wastes, and to conceive a treatment techniques of them. In order to prevent contamination, experiment appature was made of acrylic acid resin and polyethylene which resist to acid and alkali. Experiment models are devided into four groups based on the system environments, distribution patterns and a kind of filling materials. The first group is background model(model I ) which is filled with waste only and opened to air. The second one is four layer group which is subdivided into two models, opened and closed systems, and the third mix group which is subdivided into three models based on mixing ratio of filling materials and system environment like a layered group. The forth is composed of two layer model, lower one composed of waste and upper one limestone chips. Solution drained from Model Ishows a high contents of heavy metals on the all terms of experiments. Among the models, however, the closed mix model V and Ⅶ show the most effective removal of heavy metals liberated from wastes. Models having different mixing ratios of filling materials on closed systems does not affect in heavy metal removal effect. But, the distribution patterns of filling materials affect very much on removal effect of heavy metals. The closed models with same constitution ratios and distribution patterns of filling materials show more and less effective removal to the open models.

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Proteolytic Conditions for the Hydrolysate of Flounder Skin Gelatin (효소에 의한 가자미피 젤라틴 가수분해물의 제조 조건)

  • 강태중;양현필;김세권;송대진
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.21 no.4
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    • pp.398-406
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    • 1992
  • In order to develop a new flavourant using the fish skin gelatin, the proteolytic renditions for the gelatin hydrolysate of the alkali (B-type) and Alcalase (E-type) pretreated flounder (Limanda aspera) skin gelatin were investigated, and some physical properties, molecular weight and amino acid compositions of the hydrolysates were, also, compared with each other. The proteolytic conditions of the gelatins (B-type and E-type) by trypsin were as follows : reaction temperature, 55$^{\circ}C$ : pH, 9.0 : enzyme concentration, 0.1% : re-action time, 4hrs for B-type and 1 hr for E-type. The degrees of hydrolysis of the B-type and E-type gelatin un-der the renditions stated above were 63% and 82%, respectively. The rnajor molecular weights of the hydrolysates were 15,000 dalton for B-type and 12,400 dalton for E-type. Among the amino acids in the hydrolysates, glycine, alanine, proline, hydroxyproline and serine having a sweet taste were responsible for 57% of the total amino acid. But valine, leucine, phenylalanine, tyrosine, methionine, arginine and histidine having a bitter taste were only 18%.

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Catalytic Oxidation of Aromatic Compounds over Spent Ni-Mo and Spent Co-Mo based Catalysts: Effect of Physico-chemical Pretreatments (폐 Ni-Mo 및 폐 Co-Mo계 촉매상에서 방향족 화합물의 촉매산화: 물리화학적 전처리 효과)

  • Shim, Wang Geun;Kang, Ung Il;Kim, Chai
    • Applied Chemistry for Engineering
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    • v.21 no.1
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    • pp.63-70
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    • 2010
  • Transition metal based spent catalysts (Ni-Mo and Co-Mo), which were scrapped from the petrochemical industry, were reused for the removal processes of volatile organic compounds (VOCs). Especially the optimum regeneration procedures were determined using the removal efficiency of VOCs. In this work, the spent Ni-Mo and spent Co-Mo catalysts were pretreated with different physic-chemical treatment procedure: 1) acid aqueous solution, 2) alkali solution, 3) chemical agent and 4) steam. The various characterization methods of spent and its regenerated catalysts were performed using nitrogen adsorption, X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with an energy dispersive spectrometry (EDS). It was found that all spent catalysts were found to be potentially applicable catalysts for catalytic oxidation of benzene. The experimental results also indicated that among the employed physico-chemical pretreatment methods, the oxalic acid aqueous (0.1 N, $C_2H_2O_4$) pretreatment appeared to be the most efficient in increasing the catalytic activity, although the catalytic activity of spent Ni-Mo and spent Co-Mo catalysts in the oxidation of benzene were greatly dependent on the pretreatment conditions. The pretreated spent catalysts at optimum condition could be also applied for removing other aromatic compounds (Toluene/Xylene).

Regulation of Intracellular pH by SHC1 in Saccharomyces cerevisiae (효모에서 SHC1 유전자의 이온 농도 조절에 의한 세포내 pH 항상성 유지)

  • 하승길;전준철;최의열
    • Korean Journal of Microbiology
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    • v.38 no.3
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    • pp.168-172
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    • 2002
  • Budding yeasts maintain an effective system to regulate intracellular pH in response to environmental pH fluctuation. In a previous study we reported that SHC1 plays a role in cell growth at alkaline condition, not at acid pH. We constructed a null mutant deleted an entire open reading frame for SHC1. To test whether the retardation in cell growth was caused by the absence of intracellular pH buffering capacity, we measured intracellular pH with a pH-sensitive fluorescent dye, C.SNARE. The intracellular pH of the mutant cell was much higher than that of wild-type cells, indicating that the mutant cells lack some types of buffering capacity. We also investigated the level of $Na^+ and K^+$ content with atomic mass spectroscopy after alkali shock. Wild-type cell showed a higher level of intracellular K^+$ content, whereas there was no difference in $Na^+$ level. The result suggested that K^+$ is more important in the regulation of intracellular pH in yeasts.

Characteristics of Volatile Fatty Acids Release During the Hydrolysis of Rice Straw (볏짚의 가수분해과정중 유기산 생성 특성)

  • Hong, Seung-Gil;Shin, JoungDu;Heo, Jeong-Wook;Park, Woo-Kyun;Shin, Hyun-Seon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.20 no.2
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    • pp.36-43
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    • 2012
  • Objective of this study was to investigate the effects of pre-treatment of rice straw by sizes(3cm, milled), temperatures($35^{\circ}C\;and\;55^{\circ}C$), with/without NaOH treatment, and RPM on the characteristics of volatile fatty acids production. The concentration of total volatile fatty acids (TVFAs) was increased with the hydrolyzed time. Concentration of VFAs in milled rice straw was higher than that in 3 cm cut. With the alkali treatment, the concentration of TVFAs were sharply increased, which showed 3 times higher than non-treatment. Concentration of VFAs was high at 150 rpm at $35^{\circ}C$, and at 80rpm and 200 rpm at $55^{\circ}C$. Among them acetic acid was dominant, which showed the similar increase with TVFAs. It was also observed that in the case of fibrous material, the contents of cellulose and hemi-cellulose were reduced a little, but no change in lignin.