• 미생물학회지
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• 제26권2호
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• pp.73-81
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• 1988

$\alpha$-Amylase (EC.3.2.1.1) of Neurospora crassa (ATCC9279) was cloned in E. coli HB101 using shotgun method, and the enzymes isolated from both N. crassa and E. coli were compared. Chromosomal DNA isolated from the spores of N. crassa was partially digested with PstI restriction endonuclease and rejoined to pBR322 which had been digested with the same enzyme. The resulting recombinant DNA were introduced into E. coli HB101 which had competancy by treating with $CaCl_{2}$. As the result, about 8000 colonies which showed tetracycline resistance were selected and two of the colonies which had 13.5Kb recombinant plasmid exhibit starch degrading activity on starch-containing plate when treated with D-cycloserine. $\alpha$-Amylases from both N.crassa and E. coli were isolated by using ammonium sulfate precipitation, DEAE-cellulose ion exchange column chromatography and Bio-Gel P150 gel foltration column. As the result, about 81.3 fold and 5.6 fold purifications in specific activities were obtained respectively, and specific activities of the gel filtrates were 6.1u/mg and 85u/mg respectively. The properties of both enzymes were compared and they showed quite the similar patterns in optimal temperature, optimal pH and had same molecular weight about 100,000 daltons on gel filtration method. Optimal temperatures for both enzymes were $70^{\circ}C$ and optimal pH were about 6 and 10.

• Journal of Microbiology and Biotechnology
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• 제23권11호
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• pp.1554-1559
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• 2013

A protease produced by Bacillus polyfermenticus SCD was purified and characterized as a new detergent material. The protease was purified from supernatant produced by B. polyfermenticus SCD, by ammonium sulfate precipitation, ion-exchange chromatography on a DEAE-Sephadex A-50, and finally gel filtration chromatography on Sephadex G-50. The molecular mass of this enzyme was 44 kDa based on SDS-PAGE. The optimum temperature and pH were $50^{\circ}C$ and pH 8.0. The ranges of its stability to the pH and temperature were 7.0 to 9.0 and under $40^{\circ}C$, respectively. The enzyme was highly stable in the presence of the surfactants like Triton X-100 (0.1%), showing a 2-fold increase in its proteolytic activity. However, the enzyme was slightly inhibited by the chelating agent EDTA (1 mM). The enzyme has a maximum activity at $50^{\circ}C$ and the activity can be increased by surfactants such as Triton X-100 and Tween 80.

• 한국식품조리과학회지
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• 제31권3호
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• pp.335-343
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• 2015

The aim of this investigation was to examine the antioxidation, physicochemical, and sensory activity of a Korean steamed-rice cake, Sulgidduk, fortified with water extracts from Moringa oleifera (M. oleifera) leaf. M. oleifera leaf extracts were added to rice powder at rations of 0.1%, 1% and 10%. To examine antioxidation properties, the scavenging activities of DPPH radicals, hydroxyl radicals, ABTS+ radicals, and ferric ion reducing antioxidant power were investigated. M. oleifera extracts significantly increased the antioxidation activities of Sulgidduk in a dose dependent manner (p<0.05). Physicochemical characteristics were measured by proximate composition, color, texture profile analysis, and sensory evaluations. As the concentration of M. oleifera leaf extracts increased, L-values and a-values significantly decreased while b-values increased. Texture profile analysis demonstrated that the control groups showed significantly higher values for hardness, cohesiveness, chewiness, and adhesiveness as compared with groups containing M. oleifera leaf extract (p<0.05). In the sensory evaluation, the sample containing 0.1% of M. oleifera leaf extract obtained the best results in overall preference. Taken together, these results suggest that M. oleifera leaf may have the potential to increase the consumer acceptability and the functionality of Sulgidduk.

• Transactions on Electrical and Electronic Materials
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• 제16권3호
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• pp.135-138
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• 2015

A manganese dioxide (MnO₂) layer and zinc (Zn) layer are used as the cathode and the anode to develop filmtype manganese battery, in which a stack of a MnO₂ layer, gel electrolyte, and Zn layer are sandwiched between two plastic layers. This paper describes the chemical equation of swelling control upon the film-type manganese battery. We examined the reduction of hydrogen formation, by using calcium hydroxide Ca(OH)₂ as an additive in the electrolyte of film-type manganese battery. The phenomena or an effect of reduced hydrogen gas was proven by cyclic voltammogram, X-ray photoelectron spectra (XPS), and volume of hydrogen formation. The amount of H₂ gas generation in the presence of Ca²⁺ ion was reduced from 4.81 to 4.15 cc/g-zinc (14%), and the corrosion of zinc electrode in the electrolyte was strongly inhibited as time passed.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.272-272
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• 2013

The attractive features of photosynthetic reaction center proteins for energy application make them useful in solar energy conversion to hydrogen fuel or electrical energy. Almost unity charge separation quantum yield and its rapid speed of ~1ns, absorbance region in visible light (480~740 nm) and high proportion of photosynthetically active solar energy of 48.5% allowed photosystem1 to exploited as a bio-material for photo-energy devices. Directionality of photosystem1 in electron transfer can solve main problem in two-step water splitting process where back reaction deteriorates the overall efficiency. In the study, photosystem1 was extracted from spinach and the photo-induced excited electron in the reaction center was utilized in various field of light energy application. First, hydrogen evolving system realized by photodeposition of platinum at the end of the electron transfer chain, with combining specific semiconductor to oxidize water in the first step of Z-scheme. The evaluation by gas-chromatography demonstrated hydrogen evolution through the system. For the further application of photoelectrical material on electrode, photosystem1 have been controlled by copper ion, which is expected to assemble photosystem in specific orientation followed by maximized photoelectrical ability of film. The research proposed concrete methods for combining natural protein and artificial materials in one system and suggested possibility of designing interface between biological and inorganic materials.

• 산업기술연구
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• 제39권1호
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• pp.33-39
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• 2019

This paper addresses effects of nanoscale structures on structural colors of micropatterned transparent substrate by light diffraction. Structural colors is widely investigated because they present colors without any chemical pigments. Typically structural colors is presented by diffraction of light on a micropatterned surface or by multiple interference of light on a surface containing a periodic or quasi-periodic nano-structures. In this paper, each structural colors induced by quasi-periodic nano-structures, periodic micro-structures, and nano/micro dual structures is measured in order to investigate effects of nanoscale and microscale structures on structural colors in the transparent substrate. Using pre-fabricated pattern mold and hot-embossing process, nanoscale and microscale structures are replicated on the transparent PMMA(Poly methyl methacrylate) substrate. Nanoscale and microscale pattern molds are prepared by anodic oxidation process of aluminum sheet and by reactive ion etching process of silicon wafer, respectively. Structural colors are captured by digital camera, and their optical transmittance spectrum are measured by UV/visible spectrometer. From experimental results, we found that nano-structures provide monotonic colors by multiple interference, and micro-structures induce iridescent colors by diffraction of light. Structural colors is permanent and unchangeable, thus it can be used in various application field such as security, color filter and so on.

• 식물분류학회지
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• 제53권2호
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• pp.102-109
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• 2023

The basic information of ovule and seed characteristics was investigated for five monotypic and endemic genera in the Korean peninsula as categorized by the Flora of Korea category. The carpels and seeds were sectioned with a rotary microtome. Mature seeds were coated with platinum using an ion sputter and observed using a scanning electron microscope. As a result, Abeliophyllum was found to be anatropous and a unitegmic ovule, with a slightly colliculate seed surface and exotestal seed coat type. The ovule of Coreanomecon was anatropous and bitegmic, having a distinct echinate seed surface, and exo-endotestal seed coat type with a prismatic crystal in the mesotesta. The ovule of Hanabusaya was anatropous and a unitegmic, with a long reticulate seed surface sculpture, and distinct exotestal seed coat type. In addition, a wing developed at the opposite side of the raphe bundle. Megaleranthis was an anatropous and bitegmic ovule, having a small pentagonal disk shape, a concave seed surface and exotestal seed coat type. Finally, Pentactina was also anatropous and a unitegmic ovule, reticulate seed sculpture, and endotestal seed coat type. These data will be proving to be a source of good information for securing bio-sovereignty in the near future.

• Mass Spectrometry Letters
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• 제15권1호
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• pp.1-25
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• 2024

Protein glycosylation, a highly significant and ubiquitous post-translational modification (PTM) in eukaryotic cells, has attracted considerable research interest due to its pivotal role in a wide array of essential biological processes. Conducting a comprehensive analysis of glycoproteins is imperative for understanding glycoprotein bio-functions and identifying glycosylated biomarkers. However, the complexity and heterogeneity of glycan structures, coupled with the low abundance and poor ionization efficiencies of glycopeptides have all contributed to making the analysis and subsequent identification of glycans and glycopeptides much more challenging than any other biopolymers. Nevertheless, the significant advancements in enrichment techniques, chromatographic separation, and mass spectrometric methodologies represent promising avenues for mitigating these challenges. Numerous substrates and multifunctional materials are being designed for glycopeptide enrichment, proving valuable in glycomics and glycoproteomics. Mass spectrometry (MS) is pivotal for probing protein glycosylation, offering sensitivity and structural insight into glycopeptides and glycans. Additionally, enhanced MS-based glycopeptide characterization employs various separation techniques like liquid chromatography, capillary electrophoresis, and ion mobility. In this review, we highlight recent advances in enrichment methods and MS-based separation techniques for analyzing different types of protein glycosylation. This review also discusses various approaches employed for glycan release that facilitate the investigation of the glycosylation sites of the identified glycoproteins. Furthermore, numerous bioinformatics tools aiding in accurately characterizing glycan and glycopeptides are covered.

• 생물환경조절학회지
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• 제29권2호
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• pp.141-152
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• 2020

본 연구는 양액 내 존재하는 다량 영양소의 농도를 실시간으로 측정하기 위해 이온 선택 전극 (ISE) 으로 구성된 임베디드 시스템의 개발을 보여준다. NO₃, K 및 Ca 이온을 감지하기위한 PVC ISE, H₂PO₄를 감지하기위한 코발트 전극, 기준 전극, 샘플 용액이 담기는 챔버, 펌프 및 밸브를 사용하여 측정하는 시스템으로 구성된다. 양액 샘플양 조절과 데이터 수집을 위해서 데이터 Due 보드가 사용되었고, 각각의 샘플 측정 전에, 측정 중 발생하는 드리프트를 최소화시키기 위해 2 점 정규화 방법을 사용하였다. PVC 멤브레인을 기반으로 한 NO₃ 및 K 전극의 농도 예측 성능은 표준 분석기의 결과와 근접한 일치 (R² = 0.99) 나타내며 만족스러운 결과를 나타냈다. 하지만, Ca II 이온 투과체 제조된 Ca 전극은 고농도 양액 농도에서 Ca 농도를 55 %로 낮게 측정하였다. 코발트 전극 기반 인산 측정은 반복측정 중에 발생한 코발트 전극의 불안정한 신호로 인해 표준 방법과 비교하여 45 ~ 155 mg / L의 인산 농도 범위에서 24.7 ± 9.26 %의 비교적 높은 오차를 나타냈다. 수경 P 감지의 예측 능력을 향상시키기 위해 코발트 전극의 신호 컨디셔닝에 대한 추가 연구가 필요함으로 판단된다.

• 생물환경조절학회지
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• 제21권4호
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• pp.478-484
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• 2012

본 실험에서는 염토지대에 조경용 식재로 사용이 가능한지 알아보기 위해 여러 과에 속하는 자생식물의 염 스트레스에 대한 내염성 정도를 조사하였다. NaCl의 처리에 따른 식물의 생육반응과 이온흡수 특성도 파악하여, 여러 식물에 대한 내성 정도를 구명하고자 하였다. 실험재료로 노랑꽃창포, 밀사초, 여우꼬리사초, 줄사초, 홍노줄사초, 애기부들, 바위 및 땅채송화 등을 이용하였다. 염농도는 0, 100, 200, 300mM로 처리해 주었다. 처리 4주 후 지상부 및 뿌리의 생체중 건물중, 엽내 무기이온 함량 등을 조사하였다. 줄사초, 왕밀사초, 여우꼬리사초, 노랑꽃창포 등은 NaCl 200mM의 고농도에서도 잘 견디는 초종으로 판단되었다. 홍노줄사초, 애기부들 등은 지하부 생육이 NaCl 100mM의 농도에서 저하되어, 지상부다 뿌리가 민감하게 반응하는 것으로 나타났다. 홍노줄사초는 K의 흡수량이 감소되었고, Na/K의 비율은 300mM의 농도에서 3으로 다른 종보다 높은 경향을 보였다. 애기부들은 NaCl의 농도가 증가됨에 따라 K, Ca, Mg의 흡수량이 일시 증가하다가 200mM의 농도부터 감소하는 경향을 보였고, Na/K의 비율은 300mM의 농도에서 0.8로 조사되었다. 땅채송화 및 바위채송화 등도 NaCl 100~200mM의 범위에서 지상부 및 지하부의 생육이 영향을 받는 것으로 나타났다. 바위채송화는 NaCl의 농도가 증가됨에 따라 K, Ca, Mg의 흡수량이 일시 증가하다가 200mM의 농도부터 감소하는 경향을 보였고, 땅채송화는 염농도에 따라 흡수량이 영향을 받지 않는 것으로 나타났다. Na/K의 비율은 300mM의 농도에서 모두 1로 조사되었다. 그러므로, 여우꼬리사초, 왕밀사초, 줄사초, 노랑꽃창포 등은 식물의 생육 및 이온흡수 특성을 고려할 때 NaCl 200mM의 고농도에서도 잘 견디는 초종으로 판단되었고, 특히 사초과 식물들의 내염성이 검증되어 앞으로 많이 활용될 수 있으리라 사료되었다. 홍노줄사초, 애기부들, 바위채송화, 땅채송화 등은 NaCl 100mM의 농도에서도 뿌리의 생육이 저하되었으며, 염처리에 따른 잎의 이온흡수특성은 뚜렷한 경향을 보이지 않았다.