• 제목/요약/키워드: $MnO_{2}$

검색결과 2,706건 처리시간 0.03초

Characterization and Potent Application of Pleurotus floridanus Trypsin Inhibitor (PfTI)

  • Pannippara, Manzur Ali;Kesav, Sapna;Raghavan, Rekha Mol Kollakal Naduvil;Mathew, Abraham;Bhat, Sarita Ganapathy;Kozhiyil, Elyas Kothanan
    • Natural Product Sciences
    • /
    • 제26권3호
    • /
    • pp.207-213
    • /
    • 2020
  • Characterization and in vitro inhibition studies of protease inhibitor from the mushroom Pleurotus floridanus (PfTI) towards the pest Papilio demoleus is studied. The addition of 1 mM Mn2+, Na2+, Ba2+ and Ni 2+ enhanced the PfTI activity. The ICP-atomic emission spectrum showed the presence of Ca2+, Mg2+ and Zn2+ in the PfTI. Surfactants SDS and CTAB at a concentration of 1% reduced the PfTI activity whereas, the nonionic detergents Triton X and Tween 80 increased the activity. The inhibitory activity gradually decreased with increase in concentration of DMSO and H2O2. The activity was increased by dithiothreitol up to a concentration of 80 μM and inactivated at 140 μM. The activity of PMSF modified PfTI was drastically reduced to 0.234 U/mL at 4 mM concentration and similar results were obtained for modification of cysteine by N-Ethylmaleimide at slightly higher concentrations. The complex of trypsin and PfTI showed complete loss in fluorescence intensity at 343 nm compared with control. In vitro inhibition studies of PfTI with midgut proteases isolated from citrus pest P. demoleus with protease activity of 1.236 U was decreased to 0.613 U by 50 μL (0.1 mg/mL) of the inhibitor. Inhibitor was stable up to 0.04 M concentration of HCl.

임플란트 환자의 분포 및 식립부 유형 (The Distribution of Implant Patients and the Type of Implant Site)

  • 박지은;윤정호;정의원;김창성;조규성;채중규;김종관;최성호
    • Journal of Periodontal and Implant Science
    • /
    • 제34권4호
    • /
    • pp.819-836
    • /
    • 2004
  • Nowdays, the awareness of implant treatment has grown rapidly among dentists and patients alike in Korea, as it becomes a widely accepted treatment. The reason is that unlike crown and bridge or denture treatment, implant treatment helps preserve existing bone and improve masticatory functions. So, It is needed understanding about the type, distribution of implant patient. The following results on patient type and implant distribution were compiled from 4433 implant cases of 1596 patients treated at the periodontal dept. of Y University Hospital during 1992 to 2004. 1. There are no dissimilarities between men and women, with patients in their 40, 50s accounting for 52.5% of patients and 57.5% of implant treatments; the largest share of patients and implant treatments. 2. Mn. posterior area accounted for 54.9% of implant treatments followed by Mx. posterior area(27.6%), Mx anterior area(11.9%) and Mn anterior area(5.6%). 3. Partial edentulous patients treated by single crown and bridge-type prosthesis accounted for 97.5% and fully edentulous patient accounted for the remaining 2.5%. 4. The major cause of tooth loss is periodontal disease, followed by dental caries, trauma and congenital missing. Also, older people are more likely to suffer from tooth loss due to periodontal disease rather than dental caries. 5. In the distribution of bone quality for maxillae, type III was most, followed by type II, r type IV and r type I. As for mandible, type II was most, followed by type III, type IV and for type I. 6. In the distribution of bone quantity for maxillae, type C was most, followed by type B, type D, type A, and for type E. As for mandible, type B was 52% most, followed by type C, type D, type A and type E. 7. The majority of implants were those of 1O-14mm in length (85.2%) and regular diameter in width (64%). The results provided us with basic data on patient type, implant distribution, bone condition, etc. We wish that our results coupled with other research data helps assist in the further study for better implant success/survival rates, etc.

부추가 Streptozotocin 유발 당뇨쥐의 지질과산화와 항산화방어체계에 미치는 영향 (Effect of buchu (Allium tuberosum) on lipid peroxidation and antioxidative defense system in streptozotocin-induced diabetic rats)

  • 송영선;정현실;노경희;조혜연;박지영;최춘연;권태완
    • 생명과학회지
    • /
    • 제13권3호
    • /
    • pp.333-342
    • /
    • 2003
  • STZ(50mg/kg BW)을 대퇴부 근육에 주사하여 당뇨를 유발시킨 당뇨 흰쥐(Sprague Dawley, 수컷)에서 10% 부추 첨가식이가 혈액과 적혈구, 간조직의 지질과산화 정도와 항산화 효소계 활성 및 GSH 수준에 미치는 영향을 조사하였다. 실험군은 정상군, 당뇨대조군, 당뇨부추군의 3군 (n=10)으로 나누었으며 4주간 사육한 후 실험에 이용하였다. STZ로 유발된 당뇨대조군의 적혈구, 간과 LDL의 TBARS와 conjugated dienes 함량은 대조군에 비해 증가하였으나, 당뇨부추군에서는 적혈구의 conjugated dienes 수준이 유의적으로 감소하였고(p<0.05), 간과 LDL의 TBARS 수준은 당뇨대조군에 비해 다소 감소하여 정상대조군과 차이를 보이지 않았다. 간에서의 항산화 효소계 중 SOD 활성은 대조군에 비해 당뇨대조군에서 증가하였고, catalase 활성은 당뇨대조군에 비해 부추를 섭취한 당뇨군에서 유의적으로 증가하였다. GSH-px와 GSH-red 활성은 대조군에 비해 당뇨대조군에서 유의적으로 감소하였으나(p<0.05), 당뇨부추군에서는 다소 증가하였다. 간의 GSH 함량은 대조군과 당뇨대조군에 비해 당뇨부추군에서 유의적으로 증가하였으며(p<0.01), 혈장의 GSH 함량은 대조군에 비해 당뇨군에서 유의적으로 감소하였다(p<0.05). GOT와 GPT 활성은 정상대조군에 비해 당뇨대조군에서 급격히 증가하였으나 당뇨부추군에서는 정상군 수준으로 감소하였다. 이상의 결과로 미루어 볼 때, 부추는 간의 항산화효소계를 활성화시키고 간조직의 GSH수준을 높게 유지하여 고혈당과 STZ로부터 유발된 산화적 스트레스(지질과산화)를 해소함으로써 당뇨로 인한 합병증 예방 및 치료를 위한 식품자원으로 활용이 가능한 것으로 사료된다.도 및 동맥경화지수를 낮추는 효과가 있고, HDL- 콜레스테롤 농도를 증가시키는 효과가 있는 것으로 나타났다.각된다. 7) 발병부위는 대부분 막성유리연의 중간부 및 전방부 1/3에서 발생하였고 수술 결과는 저류낭종 82례 중 25례(30.5%)에서만 낭종의 파열 없이 완전제거가 가능하였으며 유표피낭종 30례 중에서는 21례(70.0%)에서 완전제거가 가능했던 것으로 나타나 저류낭종이 유표피낭종에 비해 낭종을 파열시키지 않고 완전히 제거하는 것이 더욱 어려움을 알 수 있었다. 따라서 저류낭종의 경우 낭종의 절제가 어려운 경우 수술방법으로 조대술(marsupialization)을 시행하는 것도 의미가 있을 것으로 사료된다. 8) 수술 전 후의 음성만족도를 비교한 조사 결과 조사가 가능했던 82례 중 49례(52.0%)에서 만족할 만한 결과를 보였다고 답하여 성대 폴립수술 후의 만족도와 유사한 결과를 보였다.14%, V. mimicus 10%, V. parahaemolyticus 4%, E. coli O157:H7 48%에서 증식되지 않았지만 S. typhimurium은 50%에서도 집락이 검출되었다. 젖산의 경우 V. vulnificus 2%, V. cholerae non-O1 3%, V. mimicus 4%, V. parahaemolyticus 3%, S. typhimurium 14%, E. coli O157:H7 17%에서 증식되지 않았다. 식초와 젖산은 낮은 농도에서 생선회 식중독 유발에 주 원인균이 되는 Vibrio 속의 생육을 억제하였고, S. typhimurium과 E. coli O157:H7의 생육은 비교적 약하게 나타났다.은 고농도로 갈수록 심한 영향을 미쳤으며 저 농도 에서도 폭로시간이 길어짐에 따라 나타나는 SO$_2$의영향이

게르마늄 처리가 쌀 품질에 미치는 영향 (Effect of Ge(Germanium) Treatment on Rice Quality)

  • 김덕희;김광옥
    • 한국식품영양학회지
    • /
    • 제22권4호
    • /
    • pp.701-707
    • /
    • 2009
  • This study was conducted to investigate the effects of Ge(germanium) treatment on rice quality. Rice samples were divided into the following treatment groups: control(CON: cultivated without Ge), Ge-1(cultivated with 200 kg of rough stone powder containing 1.6 mg/kg germanium per 10 ha), and Ge-2(cultivated with 500 kg of rough stone powder containing 1.6 mg/kg germanium per 10 ha). The mean total Ge level in the Ge-2 sample was 20.47 ppb. The levels of Ca and Na in the Ge-2 rice increased by 65.12 and 110.28%, respectively, when compared to the control, whereas the Zn, Mn, Fe, Mg and K content decreased by 11.44~30.50%. No significant difference in the percentage weight of C and O was observed among samples. The order of the percentage weight of P, S, and Cl was Ge-2>Ge-1>CON. The free amino acids were higher in samples from the Ge-1 and Ge-2 groups than in samples from the control. The GABA($\gamma$-aminobutyric acid) amount in the Ge-2 products was significantly high compared to other groups. The micro structure of Ge-2 showed a firmer network than the control and had a macroporous structure. Conversely, the Ge-2 products had higher scores for stickiness, hardness and overall taste when compared to the other groups. These results suggest that rice treated with rough stone powder containing germanium can be used in the production of commercially-desired functional rice.

한국산 쥐오줌풀의 지방산, 무기성분 및 유기산 조성 (Compositions of Fatty Acids, Inorganic Components and Volatile Organic Acids in Korean Valerian Roots)

  • 최영현;조장환
    • 한국약용작물학회지
    • /
    • 제2권2호
    • /
    • pp.162-167
    • /
    • 1994
  • 국내에서 자생하고 있는 광릉쥐오줌풀 및 넓은잎 쥐오줌풀의 지하부에서 지방산, 무기성분 및 휘발성 유기산의 조성을 분석한 결과는 다음과 같다. 1. 광릉 및 넓은잎 쥐오줌플의 조지방질 함량은 $3.7{\sim}4.5%$ 범위 이었고 지방산은 총11종이 동정되었는데 그중 특히 양적으로 많이 함유되어있는 linoleic acid, linolenic acid 및 palmitic acid 등은 산지에 따라 함량차이가 큰 경향을 보였다. 2. 희분함량은 $4.3{\sim}6.3%$ 이었고 무기성분중 많이 검출된 성분으로는 조규소$(SiO_2)$를 위시하여 K, Na, Ca, Mg, Al, Fe, Mn, Zn등 이었으며, Na, Fe, Zn 및 Cu 는 산지에 따라 함량차이가 큰 경향을 보였다. 3. 광릉 쥐오줌풀로 부터 분리한 산성분획으로 부터 40종의 성분을 확인하였으며 그중 dimethoxy-2-propenoic acid, 3, 4-dimethoxy benzoic acid, 4-methoxy phenyl-2-propenoic acid 이외에도 3-methyl butanoic acid(isovaleric acid), 3-methyl pentanoic acid, 2-methyl butanoic acid 등 branched-chain fatty acid 류가 양적으로 많이 검출되었다.

  • PDF

Copper/Nickel/Manganese Doped Cerium Oxides Based Catalysts for Hydrogenation of CO2

  • Toemen, Susilawati;Bakar, Wan Azelee Wan Abu;Ali, Rusmidah
    • Bulletin of the Korean Chemical Society
    • /
    • 제35권8호
    • /
    • pp.2349-2356
    • /
    • 2014
  • The recycling technology by the catalytic conversion is one of the most promising techniques for the $CO_2$ treatment of coal burning power plant flue gases. The conversion of $CO_2$ to valuable product of $CH_4$ can be used as a fuel to run the turbine for electricity generation. Through this technique, the amount of coal needed for the combustion in a gas turbine can be reduced as well as $CO_2$ emissions. Therefore, a series of catalysts based on cerium oxide doped with copper, nickel and manganese were prepared by impregnation method. From the characterization analysis, it showed that the prepared catalysts calcined at $400^{\circ}C$ were amorphous in structure with small particle size in the range below 100 nm. Meanwhile, the catalyst particles were aggregated and agglomerated with higher surface area of $286.70m^2g^{-1}$. By increasing the calcination temperature of catalysts to $1000^{\circ}C$, the particle sizes were getting bigger (> 100 nm) and having moderate crystallinity with lower surface area ($67.90m^2g^{-1}$). From the catalytic testing among all the prepared catalysts, Mn/Ce-75/$Al_2O_3$ calcined at $400^{\circ}C$ was assigned as the most potential catalyst which gave 49.05% and 56.79% $CO_2$ conversion at reaction temperature of $100^{\circ}C$ and $200^{\circ}C$, respectively.

Serratia liquefaciens AL-11이 생산하는 Alkaline Lipase의 특성 및 작용양상 (Characteristics and Action Pattern of Alikaline Lipase from Serratia liquefaciens AL-11)

  • 최청;김태완;안봉전;김영활;손준호;김성;최희진
    • 한국미생물·생명공학회지
    • /
    • 제24권1호
    • /
    • pp.87-91
    • /
    • 1996
  • The optimum temperature and pH for the enzyme activity were 45$^{\circ}C$ and 10.0, respectively. The enzyme was stable in a pH range of 5 to 10, and 62% of its activity was lost on heat treatment of 60$^{\circ}C$ for 20 min. The activity of the purified enzyme was inhibited by $Fe^{2+},\;Zn^{2+}\;and\;Pb^{2+}$, and slightly activated by $Mn^{2+}\;and\;Ca^{2+}$. ${\gamma}$-Chloromercuribenzoic acid, 2,4-dinitrophenol and $H_{2}O_{2}$ did not show inhibitroy effect on the lipolytic activity of the alkaline lipase but ethylenediaminetetraacetic acid inhibited the enzyem activity. This suggested that the enzyme have metal group in its active site. Sodium salts of bile acids stimulated the enzyme activity. Analysis of hydrolyzates of olive oil after the reaction revealed that Serratia liquefaciens AL-11 produced non-specific lipolytic enzyme.

  • PDF

Zn3(PO4)2 Protective Layer on Zn Anode for Improved Electro-chemical Properties in Aqueous Zn-ion Batteries

  • Chae-won Kim;Junghee Choi;Jin-Hyeok Choi;Ji-Youn Seo;Gumjae Park
    • Journal of Electrochemical Science and Technology
    • /
    • 제14권2호
    • /
    • pp.162-173
    • /
    • 2023
  • Aqueous zinc-ion batteries are considered as promising alternatives to lithium-ion batteries for energy storage owing to their safety and cost efficiency. However, their lifespan is limited by the irreversibility of Zn anodes because of Zn dendrite growth and side reactions such as the hydrogen evolution reaction and corrosion during cycling. Herein, we present a strategy to restrict direct contact between the Zn anode and aqueous electrolyte by fabricating a protective layer on the surface of Zn foil via phosphidation method. The Zn3(PO4)2 protective layer effectively suppresses Zn dendrite growth and side reactions in aqueous electrolytes. The electrochemical properties of the Zn3(PO4)2@Zn anode, such as the overpotential, linear polarization resistance, and hydrogen generation reaction, indicate that the protective layer can suppress interfacial corrosion and improve the electrochemical stability compared to that of bare Zn by preventing direct contact between the electrolyte and the active sites of Zn. Remarkably, MnO2 Zn3(PO4)2@Zn exhibited enhanced reversibility owing to the formation a stable porous layer, which effectively inhibited vertical dendrite growth by inducing the uniform plating of Zn2+ ions underneath the formed layer.

재조합균주 E. coli CNU312가 생산하는 Catechol 2,3-Dioxygenase의 정제 및 특성 (Purification and Characterization of Catechol 2,3-Dioxygenase from Recombinant Strain E. coli CNU312.)

  • 임재윤;최경호;최병돈
    • 미생물학회지
    • /
    • 제36권1호
    • /
    • pp.26-32
    • /
    • 2000
  • Toluene, phenyl 등의 분해균주인 Burkholderia cepacia G4로부터 tomB 유전자를 클로닝하여 얻은 재조합 균주 E. coli CNU312로부터 catechol 2,3-dioxygenase를 정제하여 효소학적 특성을 조사하였다. Catechol 2,3-dioxygenase는 native 분자량이 약 140.4 kDa이었으며 4개의 동일한 35 kDa subunit로 구성된 homotetramer로 생각된다. Catechol의 $K_(m)$값과 $V_(max)$값은 372.6 $\mu$M과 39.27 U/mg이었으며, 1.56 mM 이상의 기질 농도에서는 활성이 감소되었다. 효소 활성의 최적 pH는 8.0이었으며, pH 7.0-8.0 범위에서 안정하였다. 최적 활성온도는 $40^{\circ}C$였으며, $60^{\circ}C$이상에서 완전히 활성을 상실하였다. 또한 $Fe^(2+)$, $Fe^(3+)$ 를 비롯한 대부분의 금속 이온에 의해 활성이 감소되었으며, $Mg^(2+)$, $K^(+)$에는 영향을 받지 않았다. 효소 활성부위를 알아보기 위해 화학변형제를 처리한 결과, tryptophan과 histidine이 효소 활성부위에 존재하는 것으로 추정된다. 그리고 10%의 유기용매에 안정성을 보이지 않았으며, $H_(2)$$O_(2)$, EDTA, ο-phenanthroline에도 활성이 감소되었다. 또한 2-mercaptoethanol, dithiothreitol, 그리고 ascorbic acid와 같은 환원제에 대해서도 안정성을 보이지 않았다. 이 효소는 catechol에 대해 높은 기질 특이성을 보였으며, 3-methylcatechol, 4-methylcatechol, 그리고 4-chlorocatechol에 대해 약간의 활성을 보였다. 그러나 2,3-dihydroxybiphenyl에 대해서는 거의 활성을 보이지 않았다.

  • PDF

부산 해운대지역 지하수와 지열수의 수리화학적 특성 (Hydrochemical characteristics of ground and geothermal waters in the Haeundae hot-spring area, Pusan, Korea)

  • 심형수;함세영;성익환;이병대;조병욱;황진연
    • 한국환경과학회지
    • /
    • 제9권3호
    • /
    • pp.241-252
    • /
    • 2000
  • Twenty-two water samples(fifteen groundwater and seven geothermal water samples) were collected to elucidate chemical characteristics of the ground and geothermal waters in the Haeundae hot spring area and its vicinity. Major and honor elements were analyzed for ground and geothermal water samples. The concentrations of $K^+$, Na+$, $Ca^{2+}$, $SO_4^{2-}$, $Cl^-$, ^F^-$ and $SiO_2$ were higher in the geothermal water samples than the groundwater samples except $HCO_3^- and Mg^{2+}$ ions. Based on the contents of Fe, Zn, Cu, Al, Mn and Pb, some of the ground and geothermal water samples are contaminated by anthropogenic sources. The ground waters shown on the Piper diagram belong to $Ca-HCO_3$ type, while the geothermal waters Na-Cl type. The graphs of $Cl^-$ versus $Na^+$, $Ca^{2+}, Mg^{2+}, K^+, SO_4^{2-} and HCO_3^-$ indicate that the groundwater is related partly with mineral-water reaction and partly with anthropogenic contamination, while the geothermal water is related with saline water. On the phase stability diagram, groundwater and thermal water mostly fall in the field of stability of kaolinite. This indicates that the ground and geothermal waters proceed with forming kaolinite. Factor and correlation analyses were carried out to simplify the physicochemical data into grouping some factors and to find interaction between them. Based on the Na-K, Na-K-Ca and Na-K-Ca-Mg geothermometers and silica geothermometers, the geothermal reservoir is estimated to have equilibrium temperature between 125${$\mid$circ}C$ and 160${$\mid$circ}C$.

  • PDF