• Journal of Applied Biological Chemistry
• /
• 제53권3호
• /
• pp.179-183
• /
• 2010

각종 버섯에서 항보체 활성균주를 선별하기 위해 보관균주 50여종과 임업협동조합에서 분양 받은 20여종의 균주를 대상으로 항보체 활성을 검색한 결과, 항보체 활성이 65.3%를 나타낸 상황버섯 (Phellinus linteus)을 선별하였다. 본 균주가 생산하는 항보체 활성의 본체를 파악하기 위해 pronase 처리와 periodate 산화를 행한 결과 pronase로 처리한 사료는 무처리군과 비교하여 차이가 없었던 반면 periodate로 산화시킨 시료는 항보체 활성이 크게 감소함에 따라 P. linteus가 생산하는 항보체 활성의 본체는 다당에 기인되는 것으로 추정되었다. 항보체 생산을 위한 최적 배양조건은 soluble starch 3.0%, peptone 0.3%, yeast extract 0.4%, $MgSO_4{\cdot}7H_2O$ 0.1%, $K_2HPO_4$ 0.2%, 초기 pH 7.0, 배양 온도 $30^{\circ}C$ 및 교반속도 150rpm이었다. 상기의 최적 배양조건에서 jar fermentor로 18일 배양하였을 때 88%의 항보체 활성과 15mg/mL의 균사체 생육을 나타내었다.

• 한국균학회지
• /
• 제39권2호
• /
• pp.117-121
• /
• 2011

각종 버섯에서 항혈전 활성균주를 선별하기 위해 보관 균주 50여종과 임업협동조합에서 분양 받은 20여종의 균주를 대상으로 항혈전 활성을 검색한 결과, 항혈전 활성이 167 sec를 나타낸 상황버섯(Phellinus linteus)을 선별하였다. 본 균주가 생산하는 항혈전 활성의 본체를 파악하기 위해 pronase 처리와 periodate 산화를 행한 결과 pronase로 처리한 시료는 무처리군과 비교하여 차이가 없었던 반면 periodate로 산화시킨 시료는 항혈전 활성이 크게 감소함에 따라 P. linteus가 생산하는 항혈전 활성의 본체는 다당에 기인되는 것으로 추정되었다. 항혈전 생산을 위한 최적 배양조건은 soluble starch 3.0%, peptone 0.1%, $MgSO_4{\cdot}7H_2O$ 0.1%, $K_2HPO_4$ 0.1%, 초기 pH 7.0, 배양온도 $30^{\circ}C$ 및 교반속도 150 rpm이었다. 상기의 최적 배양조건에서 jar fermentor로 10일 배양하였을 때 390 sec의 항혈전 활성과 7.5 mg/mL의 균사체 생육을 나타내었다.

• 한국미생물·생명공학회지
• /
• 제17권4호
• /
• pp.358-364
• /
• 1989

토양으로부터 분리한 Streptomyces sp. YSA-130으로부터 활성이 좋은 결정화된 alkaline protease를 분리하였다. Alkaline protease 생산의 최적 배양조건은 2.0% soluble starch, 1.0% soytone, 0.3% $K_2$HPO$_4$, 0.02% MgSO$_4$.7$H_2O$, 0.8% $Na_2$CO$_3$ 3$0^{\circ}C$, pH 10.5에서 72 시간 배양하였을 때 였다. Alkaline protease이 정제는 (NH$_4$)$_2$SO$_4$. 분별침전, 투석, DEAE cellulose column chromatography, Sephadex G-75 gel filtration, crystallization으로 하였으며, 그 결과 비활성도 14,290unit/mg, 정제도 23.8 배였고, 수율은 20.0% 이었다. Alkaline protease의 반응 최적온도와 pH는 6$0^{\circ}C$ 와 11.5이었으며, 효소의 pH 안정성은 5.5-12.0에서 안정하였고, 온도 안정성은 5$0^{\circ}C$까지 안정하였으며, $Ca^{++}$ ion 첨가시 6$0^{\circ}C$까지 안정성이 증가하였다. Alkaline protease의 분자량은 30,000이었으며 금속이온, EDTA, 환원제는 활성에 영향이 없었고 DFP에 의해 저해되었다. 계면활성제에 저항성이 크고 $H_2O$$_2$에 대한 잔존활성은 60% 을 유지하였다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
• /
• pp.88-91
• /
• 2003

Tungsten is widely used as a plug for the multi-level interconnection structures. However, due to the poor adhesive properties of tungsten (W) on $SiO_2$ layer, the Ti/TiN barrier layer is usually deposited onto $SiO_2$ for increasing adhesion ability with W film. Generally, for the W-CMP (chemical mechanical polishing) process, the passivation layer on the tungsten surface during CMP plays an important role. In this paper, the effect of oxidants controlling the polishing selectivity of W/Ti/TiN layer were investigated. The alumina ($Al_2O_3$) abrasive containing slurry with $H_2O_2$ as the oxidizer, was studied. As our preliminary experimental results, very low removal rates were observed for the case of no-oxidant slurry. This low removal rate is only due to the mechanical abrasive force. However, for Ti and TiN with $H_2O_2$ oxidizer, different removal rate was observed. The removal mechanism of Ti during CMP is mainly due to mechanical abrasive, whereas for TiN, it is due to the formation of metastable soluble peroxide complex.

• Journal of the Korean Wood Science and Technology
• /
• 제45권3호
• /
• pp.317-326
• /
• 2017

산사나무 목질부 및 수피부를 70% acetone 수용액으로 추출하고 목질부는 n-hexane, chloroform ($CHCl_3$), n-butanol (n-BuOH) 및 수용성 추출물로 분획하였으며, 수피부는 n-hexane, chloroform, ethylacetate (EtOAc) 및 수용성으로 분획한 후, 각 추출 분획에 대하여 항산화 및 항염활성 평가를 실시하였다. 항산화 활성은 목질부에서는 n-BuOH용성이, 수피부에서는 EtOAc용성이 가장 좋은 활성을 보였으며, 특히 수피부 EtOAc용성은 대조군으로 사용된 buthylated hydroxytoluene (BHT) 및 ${\alpha}$-tocopherol에 비하여 매우 우수한 항산화 활성을 나타냈다. 항염활성은 목질부 수용성을 제외한 모든 분획물들이 nitric oxide (NO) 생성을 억제하는 효과를 보이고 있었으며, 수피부 조추출물과 수용성 분획에서 가장 우수한 NO 생성 억제효과를 나타내었다. 이와 같은 결과를 토대로 볼 때, 산사나무 추출물은 항산화제 및 항염제로 이용될 수 있는 천연 바이오매스 자원으로써의 가능성을 나타내었다.

• 한국대기환경학회지
• /
• 제11권1호
• /
• pp.57-68
• /
• 1995

Precipitation samples were collected by a wet-only automatic acid precipitation sampler at Kangwha island on the western coast in Korea, through January until December 1992. pH, electric conductivity and the concentrations of major water-soluble ion components such as N $H_{4}$$^{+}$, $Ca^{2+}$, $K^{+}$, $Mg^{2+}$, N $a^{+}$, N $O_{3}$$^{[-10]}$ , S $O_{4}$$^{2-}$ and C $l^{[-10]}$ were measured. From the result of checking the validity for assesment of pollution level of precipitation samples by pH using correlation analysis between pH and major components, and t-test of chemical composition between acid rain and non-acid rain, pH proved to be not satisfactory for its pillution level. A more comprehensive method is therefore required. In order to estimate the monthly analytical result of chemical composition of precipitation samples comprehensively, a cluster analysis was used among the various multivariate statistical analysis. As a result of making a cluster analysis for separating the monthly precipitation samples into homogeneous patterns by setting the concentrations of nine major water-soluble ion components as a variable, three homogeneous patterns were obtained. The first pattern was a group of months having average ion concentrations, the second a guoup of months having low ion concentration, and the third a group of months having high ion concentrations. Thus, it was indicated that the pollution level of precipitation was higher on February and lower on May, June, August and September than the other months. As a result, this analysis method could be estimated the chemical coposition of precipitation regionally as well as monthly.monthly.

• The Korean Journal of Physiology and Pharmacology
• /
• 제20권3호
• /
• pp.315-324
• /
• 2016

Human cardiac fibroblasts (HCFs) have various voltage-dependent $K^+$ channels (VDKCs) that can induce apoptosis. Hydrogen peroxide ($H_2O_2$) modulates VDKCs and induces oxidative stress, which is the main contributor to cardiac injury and cardiac remodeling. We investigated whether $H_2O_2$ could modulate VDKCs in HCFs and induce cell injury through this process. In whole-cell mode patch-clamp recordings, application of $H_2O_2$ stimulated $Ca^{2+}-activated$ $K^+$ ($K_{Ca}$) currents but not delayed rectifier $K^+$ or transient outward $K^+$ currents, all of which are VDKCs. $H_2O_2-stimulated$ $K_{Ca}$ currents were blocked by iberiotoxin (IbTX, a large conductance $K_{Ca}$ blocker). The $H_2O_2-stimulating$ effect on large-conductance $K_{Ca}$ ($BK_{Ca}$) currents was also blocked by KT5823 (a protein kinase G inhibitor) and 1 H-[1, 2, 4] oxadiazolo-[4, 3-a] quinoxalin-1-one (ODQ, a soluble guanylate cyclase inhibitor). In addition, 8-bromo-cyclic guanosine 3', 5'-monophosphate (8-Br-cGMP) stimulated $BK_{Ca}$ currents. In contrast, KT5720 and H-89 (protein kinase A inhibitors) did not block the $H_2O_2-stimulating$ effect on $BK_{Ca}$ currents. Using RT-PCR and western blot analysis, three subtypes of $K_{Ca}$ channels were detected in HCFs: $BK_{Ca}$ channels, small-conductance $K_{Ca}$ ($SK_{Ca}$) channels, and intermediate-conductance $K_{Ca}$ ($IK_{Ca}$) channels. In the annexin V/propidium iodide assay, apoptotic changes in HCFs increased in response to $H_2O_2$, but IbTX decreased $H_2O_2$-induced apoptosis. These data suggest that among the VDKCs of HCFs, $H_2O_2$ only enhances $BK_{Ca}$ currents through the protein kinase G pathway but not the protein kinase A pathway, and is involved in cell injury through $BK_{Ca}$ channels.

• 전자공학회논문지A
• /
• 제30A권5호
• /
• pp.30-35
• /
• 1993

We have investigated microwave dielectric properties of TiO$_{2}$ added (Pb$_{1-x}$Ca$_{x}$)ZrO$_{3}$ Ceramics with x=0.33, 0.35, and 0.37 sintered at 1400$^{\circ}C$ for 2 h. For additions of up to 3wt% of TiO$_{2}$ in (Pb$_{0.63}$ Ca$_{0.37}$)ZrO$_{3}$ (x=0.37), TiO$_{2}$ was completely soluble in (Pb, Ca)ZrO3 phase and did not affect the grain size of ceramics. Dielectric constant and temperature coefficient of resonant frequency increased due to the formation of solid solution, whereas Q value decreased linearly as TiO$_{2}$ increased up to 1 wt%. However, the dielectric loss was very high as TiO$_{2}$ exceeded 2 wt%. It was also shown that as Ca ion content in 0.5 wt% TiO$_{2}$ added (Pb$_{1-x}$,Ca$_{x}$)ZrO$_{3}$ decreased from x=0.37 to x=0.33, dielectric constant increased and Q value decreased.

• Food Science and Biotechnology
• /
• 제14권5호
• /
• pp.614-620
• /
• 2005

The antioxidative effect of Ecklonia cava, a brown marine alga, was investigated on radical scavenging, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), and hydroxyl and alkyl radicals, using an electron spin resonance (ESR) technique, and on the inhibition of $H_2O_2$-induced DNA damage using comet assay. E. cava was enzymatically hydrolyzed with five food industrial proteases (Alcalase, Flavourzyme, Kojizyme, Neutrase and Protamex) to prepare water-soluble extracts. All the proteolytic hydrolysates exhibited strong dose-dependent radical scavenging activities (above 80%) at a concentration of $2.5\;{\mu}g/mL$. Kojizyme extract (obtained by proteolytic hydrolysation of E. cava with Kojizyme) showed the highest hydroxyl radical scavenging activity of around 98%. In addition, the $H_2O_2$-induced DNA damage was determined using a comet assay, which was quantified by measuring the tail length. Reduction of DNA damage increased with increasing concentrations of Kojizyme extract from E. cava. These results indicated that E. cava has a potential as a valuable natural antioxidative source.

• Fisheries and Aquatic Sciences
• /
• 제24권12호
• /
• pp.406-414
• /
• 2021

The objective of this study was to investigate the yield and characteristics of collagen protein extracted from the muscle of four different species of mantis shrimp: Miyakella nepa, Harpiosquilla harpax, Erugosquilla woodmasoni, and Odontodactylus cultrifer. Mantis shrimp muscle was extracted by using a pepsin-solubilization technique, with 0.5 M acetic acid and 5% pepsin enzyme. The highest collagen yield was from M. nepa muscle (0.478 ± 0.06%), which was significantly greater (p < 0.05) than that from H. harpax, O. cultrifer, and E. woodmasoni (0.313 ± 0.03%, 0.123 ± 0.02%, and 0.015 ± 0.00%, respectively). The freeze-dried collagen appeared as thin fibers, and formed an opaque film. The pepsin-soluble collagen (PSC) from four mantis shrimp species was analyzed by gel electrophoresis. The results showed that all species of mantis shrimp contained type I collagen, consisting of β, α1, and α2 subunits with average molecular weights of 250, 145, and 118 kDa, respectively. The study of the solubility of collagen showed that, for NaCl, collagen had the highest relative solubility in 2% NaCl (80.20 ± 4.95%). In contrast, the solubility decreased at higher NaCl concentrations. However, in terms of pH, collagen had the highest relative solubility at pH 3 (91.32 ± 5.14%), and its solubility decreased at higher pH. FT-IR spectroscopy was used to compare the collagen with a model compound. Five wavenumbers in the spectrum for model collagen were identified: Amide A (3,406-3,421 cm^-1), amide B (2,916-2,940 cm^-1), amide I (1,639-1,640 cm^-1), amide II (1,539-1,570 cm^-1), and amide III (1,234-1,250 cm^-1).