• Title/Summary/Keyword: pH dependent

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Asparagine Biosynthesis in Soybean Sprouts (콩나물의 Asparagine 생합성(生合成)에 관(關)한 연구(硏究))

  • Byun, Si-Myung;Huh, Nam-Eung;Lee, Chun-Yung
    • Applied Biological Chemistry
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    • v.20 no.1
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    • pp.33-42
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    • 1977
  • Asparagine biosynthesis by soybean sprouts grown under the dark conditions has been demonstrated. The amount of free asparagine synthesized in ten day-old soybean sprouts increases to 22.7% on the dry weight base. The effects of nitrogen compounds such as $NH_4Cl,\;(NH_4)_2SO_4$ and urea on asparagine synthesis during the sprouting were examined and the results showed that urea was more effective than other two compounds. Glutamine-dependent asparagine synthetase was partially purified (8.6 folds) through ammonium sulfate fractionation, followed by Sephadex G-150 gel filtration. The enzyme was very labile and required protection by thiol groups or high level of glycerol. The mixture of ATP and $Mg^{++}$ ion also stabilized the enzyme activity. The enzyme utilized glutamine more effectively than ${NH_4}^+$ as an amide donor for the formation of asparagine. The enzyme required L-aspartate (Km=3.1 mM), L-glutamine, ATP and $Mg^{++}$. It showed pH optimum of 7.5 and catalyzed the formation of ${\beta}-aspartyl$ hydroxamate in the presence of L-aspartate, ATP, $Mg^{++}$ and $NH_2OH$ in the reaction mixture.

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Granulation of Natural Zeolite Powder Using Portland Cement (포트랜드 시멘트를 이용한 천연 지올라이트 미분의 입단화)

  • Kim, Su-Jung;Zhang, Yong-Seon;Ok, Yong-Sik;Oh, Sang-Eun;Yang, Jae-E.
    • Korean Journal of Environmental Agriculture
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    • v.26 no.3
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    • pp.259-266
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    • 2007
  • Enormous amount of zeolite by-products as a fine powder have been produced while manufacturing commercial zeolite products. Granulation of the zeolite by-products is necessary in order for them to be recycled as soil conditioners or absorbent for various environmental contaminants due to the limitations inherent from their physical properties. We granulated the zeolite powders using Portland cement as a cementing agent and characterized the physical and chemical properties of the granulated zeolite product. The experimental natural zeolite had a Si/Al ratio of 4.8 and CEC of 68.1 $cmol_c\;kg^{-1}$. The X-ray diffractometry (XRD) revealed that clinoptilolite and mordenite were the major minerals of natural zeolite. Smectite, feldspar and quartz also existed as secondary minerals. Optimum conditions of granulated zeolite production occurred when natural zeolite was mixed with Portland cement at a 4:1 ratio and granulated using the extruder, left to harden for one month at $25^{\circ}C$ and treated at $400^{\circ}C$ for 3 hours. The wide spectra of XRD revealed that the granulated zeolite had amorphous oxide minerals. The alkali- or thermal-treated natural zeolite exhibited pH-dependent charge properties. The major minerals of the granulated zeolite were clinoptilolite, mordenite and tobermorite. The buffering capacity and charge density of the granulated zeolite were greater than those of natural zeolite.

Use of Hydrogen Peroxide with Ozone to Simultaneously Reduce MIB and Quench Ozone Residual in Existing Water Treatment Plants Sourcing Water from the Han River (한강을 원수로 하는 오존/과산화수소 고도정수처리공정에서의 MIB제거 및 잔류오존 농도에 관한 연구)

  • McAdams, Stephen R.;Koo, Bon Jin;Jang, Myung Hoon;Lee, Sung Kyoo
    • Journal of Korean Society on Water Environment
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    • v.28 no.5
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    • pp.704-716
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    • 2012
  • This paper provides a detailed account of pilot testing conducted at South Lake Tahoe (California), the Ddukdo (Seoul) water treatment plant (WTP) and the Bokjung (Seongnam) WTP between February, 2010, and February, 2012. The objectives were first, to characterize the reactions of ozone with hydrogen peroxide (Peroxone) for Han River water following sand filtration, second to determine empirical ozone and hydrogen peroxide doses to remove a taste-and-odor surrogate 2-methylisoborneol (MIB) using an advanced oxidation process (AOP) configuration and third, to determine the optimum dosing configuration to reduce residual ozone to a safe level at the exit of the process. The testing was performed in a real-time plant environment at both low- and high seasonal water temperatures. Experimental results including ozone decomposition rates were dependent on temperature and pH, consistent with data reported by other researchers. MIB in post-sand-filtration water was spiked to 40-50 ng/L, and in all cases, it was reduced to below the specified target level (7 ng/liter) and typically non-detect (ND). It was demonstrated that Peroxone could achieve both MIB removal and low effluent ozone residual at ozone+hydrogen peroxide doses less than those for ozone alone. An empirical predictive model, suitable for use by design engineers and operating personnel and for incorporation in plant control systems was developed. Due to a significant reduction in the ozone reaction/decomposition at low winter temperatures, results demonstrate the hydrogen peroxide can be "pre-conditioned" in order to increase initial reaction rates and achieve lower ozone residuals. Results also indicate the method, location and composition of hydrogen peroxide injection is critical to successful implementation of Peroxone without using excessive chemicals or degrading performance.

Quality Characteristics and Antioxidative Effect of Cookies Made with Capsosiphon fulvescens Powder (매생이 분말을 첨가하여 제조한 쿠키의 품질특성과 항산화효과)

  • Lee, Ga-Wha;Choi, Min-Ja;Jung, Bok-Mi
    • Korean journal of food and cookery science
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    • v.26 no.4
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    • pp.381-389
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    • 2010
  • In this study, we investigated the quality characteristics of cookies containing mesangi powder (MP). The cookies were stored at 30 $^{\circ}C$ for 28 days. The pH of the dough decreased significantly upon the addition of MP. The spread factor of the cookies also decreased significantly with more MP added to the cookie recipe. The loss rate of cookies was significantly higher in 3% and 5% cookies than in control and 7% cookies. The leavening rate was significantly decreased upon the addition of MP. Hardness was significantly higher in 5% and 7% cookies than in control cookies. The L, a, b values of cookies were significantly reduced at higher MP content. The results of sensory evaluation showed that cookies made with MP did not differ significantly from the control, except in color and moistness. The mineral contents of cookies increased in dose-dependent fashion with MP concentration. The acid and peroxide values were lower in cookies with 5% MP than other cookies.

Characteristics of Solidified Cement of Electrokinetically Decontaminated Soil and Concrete Waste (동전기 제염 토양 및 콘크리트 폐기물의 시멘트 고화 특성)

  • Koo, Daeseo;Sung, Hyun-Hee;Hong, Sang Bum;Seo, Bum Kyoung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.1
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    • pp.83-91
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    • 2018
  • While using an electrokinetic method to analyze the characteristics of cement solidification of radioactive wastes from decontaminated uranium soil and concrete, the compressive strength, pH, electrical conductivity, irradiation effects, and volume expansion were measured for the solidified cement specimens. The workability of cement solidified from radioactive waste was about 170-190%. After the solidified cement was irradiated, the compressive strength decreased by about 15%, but met the criteria ($34kgf{\cdot}cm^{-2}$) of KORAD (Korea Radioactive Waste Agent). According to the results of SEM-EDS for solidified cement, the aluminum phase was well combined with cement, while the calcium phase was separated from cement. The volume of solidified cement in radioactive wastes was dependent on the waste-to-cement ratio and the amount of water, and increased by about 30% under the conditions used in this study. Therefore, it was concluded that permanent disposal of electrokinetically decontaminated radioactive wastes is appropriate.

Application and High Throughput Screening of DPPH Free Radical Scavenging Activity by Using 96-Well Plate (96-well plate를 이용한 DPPH free radical 소거활성 측정과 그 응용)

  • Choi, Jung-Sup;Oh, Jung-Im;Hwang, In-Taek;Kim, Sung-Eun;Chun, Jae-Chul;Lee, Byung-Hoi;Kim, Jin-Seok;Kim, Tae-Joon;Cho, Kwang-Yun
    • The Korean Journal of Pesticide Science
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    • v.7 no.2
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    • pp.92-99
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    • 2003
  • A 96-well plate was applied to determine the DPPH free radical scavenging activity using 107 plant-specific enzyme inhibitors and 100 unknown plant-originated extracts. The final optimum volume was $250{\mu}L$ containing $100{\mu}M$ DPPH ethanolic solution at pH 7.8. In this condition, the radical scavenging activities were significantly increased by two known antioxidants consisting of ascorbate and a-tocopherol in a concentration-dependent manner. Among the 107 inhibitors, ampicillin and gallic acid showed 90.2% and 92.6% antioxidant activity at $100{\mu}M$, respectively, and these results were consisted with previous findings. In the tested 100 natural materials at $50{\mu}g/mL$, antioxidant activity of AT-407 resulted in the highest of 90.1%, and 10 extracts including AT-388 and AT-443 showed over 70%. Our results suggest that the use of 96-well plate for determining DPPH free radical scavenging activity would be a suitable method to select antioxidant-like substances of both synthetic compounds and natural products.

Antioxidant and Anticancer Activities of Ginseng Treated with Traditional Rice Wine Steam Process Method (전통적 탁주증자법으로 처리한 홍삼의 일부 항산화 및 항암효과)

  • Ye, Eun-Ju;Kim, Soo-Jung;Park, Chang-Ho;Bae, Man-Jong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.5
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    • pp.599-604
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    • 2005
  • The aim of this study was to develop the new processing method for ginseng. To investigate the efficacy of the new product (the traditional rice wine steamed-red ginseng: RWS-RGS), antioxidant and anticancer effects of RWS-RGS were examined. The DPPH radical scavenging effect of RWS-RGS extracted with ethanol was increased in dose-dependent manner Especially, A3 ($3^{rd}$ traditional rice wine steamed-red ginsengs) exhibited effective DPPH radical scavenging activity. Nitrite scavenging effect of white ginseng (W.G), red ginseng (R.G) and RWS-RGS ($A1\~A9:\;1^{st}$ traditional rice wine steamed-red $ginseng\~9^{th}$ traditional rice wine steamed-red ginseng) were $25.9{\pm}4.4\%,\;12.9{\pm}1.1\%\;and\;26.2{\pm}0.1\~56.1{\pm}0.6\%$ at pH 1.2, respectively. The antitumor effects of W.G, R.G and RWS-RGS (A9) were examined in Hep3B cancer cells. Their growth inhibition against Hep3B cancer cells showed $19.6{\pm}4.5\%,\;54.5{\pm}6.1\%,\;96.3{\pm}2.4\%$ at 5,000 ppm, respectively. These result suggest that the traditional rice wine steamed ginseng will be useful product with antioxidant and antitumor effect.

Activation of Intestinal Immune System by an Orally Administered Methanol Extract from Pine Needles (솔잎 메탄올추출물의 마우스 경구투여에 의한 장관면역 활성)

  • Yoon, Jin-A;Yu, Kwang-Won;Shin, Shun-Hyuck;Cho, Hong-Yeon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.3
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    • pp.356-362
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    • 2010
  • When pine (Pinus densiflora) needles were fractionated into cold water (PD-CW), hot water (PD-HW) and methanol extract (PD-M), PD-M showed potent simulating activity (1.19-fold of the saline control) for proliferation of bone marrow cells mediated by Peyer's patch cells in vitro. MeOH extracts were prepared by homogenization, stirring or reflux to identify the method of methanol extraction, and MeOH extract by reflux method showed significantly highest intestinal immune system modulating activity (1.30-fold) in vitro. The intestinal immune system modulating effect of orally administered PD-M fractionated from pine needles also were studied in mice. Analyzing intestinal immune system modulating activity mediated Peyer's patch cells from C3H/He mice which had been fed with PD-M at different doses for 7 days, 1.0 g/kg of BW/day indicated that the bone marrow cells had proliferated (3.65-fold of 3% EtOH administered group). In addition, the amounts of IL-6 in the culture supernatant of Peyer's patch cells at 1.0 g/kg of BW/day were increased (1.13-fold) whereas the production of GM-CSF was not dose dependent. These results indicate that oral administration of PD-M enhances the secretion of hematopoietic growth factors such as GM-CSF and IL-6 from Peyer's patch cells, and these cytokines also act on modulator of bone marrow cell proliferation.

Optimization for Mycelial Growth and Inhibitory Effect on Nitric Oxide Production of Cordyceps nutans Pat. (노린재동충하초의 배양 최적화 및 NO 생성 저해 효과)

  • Lee, Ki-Man;Lee, Geum-Seon;Nam, Sung-Hee;Lim, Sung-Cil;Kang, Tae-Jin
    • Korean journal of applied entomology
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    • v.50 no.4
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    • pp.307-314
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    • 2011
  • Cordyceps (vegetable wasp and plant worm), an entomopathogenic fungi, has been used as a herbal medicine in Asian countries since ancient times. Cordyceps nutans is common but there is little research on this species. This study investigated the optimal culture conditions of C. nutans and the inhibitory effect on nitric oxide (NO) production in RAW 264.7 cell treated culture broth. The optimal conditions for the mycelial growth were $25^{\circ}C$ and pH 7.0-8.0. Mycelial growth was highest on mushroom complete medium (MCM), V8 juice agar (V8A), and yeast malt dextrose (YMD) medium. Mycelial growth on mushroom minimal medium (MMM) did not occur, so nutrient source was essential. Dextrose and sucrose as carbon sources, and ammonium citrate as a nitrogen source were satisfactory for mycelial growth. Cytotoxicity of C. nutans culture broth was not found in RAW 264.7 cells. C. nutans culture broth suppressed NO production of lipopolysaccharide (LPS)-stimulated RAW 264.7 cell in a dose-dependent manner. Thus, our results provided the optimal conditions for cultivation of C. nutans and showed that C. nutans may have excellent physiological activities.

Assessment of Skin Toxicity Using Skin Equivalents Containing Cervi cornus Colla (녹각교 함유 인공피부를 이용한 피부독성도의 검사)

  • Kim, Jandi;Li, Hailan;Jeong, Hyo-Soon;Yun, Hye-Young;Baek, Kwang Jin;Kwon, Nyoun Soo;Choi, Hye-Ryung;Park, Kyoung-Chan;Kim, Dong-Seok
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.1
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    • pp.31-38
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    • 2013
  • To substitute animal test, skin equivalents (SEs) have been developed for skin irritation and corrosion test. Recently, we have developed new SEs containing Cervi cornus Colla (CCC). In the present study, we used the SEs for cutaneous cytotoxicity test. Sodium dodecylsulfate (SDS) or sodium carbonate was applied to the SEs-, and the epidermal damage by H&E and immunohistochemical stains was evaluated. Our results showed that SDS or sodium carbonate affected the epidermal part of SEs containing CCC in a dose-dependent manner and decreased the expression of p63. It is concluded that SEs containing CCC could be used for an alternative model of animal test and would be greatly helpful in the development of in vitro irritation and corrosion test.