• Applied Microscopy
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• 제25권4호
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• pp.71-82
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• 1995

The ultrastructure and storage reserves of the Capsicum annuum seeds were studied in order to identify structure and to localize storage components in the endosperm using light microscopy, scanning and transmission electron microscopy. The seed coat was composed of one cell layer which contained a large number of lipid bodies, while most of the endosperm cells did not showed many lipid bodies. During seed maturation, the endosperm cells were continuously degenerated by the autophagy. Various types of plastids were also distinguished in the endosperm cells. They contained starch grains surrounded by electron-dense tiny particles, plastoglobuli, and vasicular bodies.

• 한국작물학회지
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• 제46권5호
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• pp.352-359
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• 2001

Cookie baking properties and relationships between cookie baking properties and flour characteristics were evaluated for two years, 1997 and 1998, and at two locations, Suwon and Deokso, with Korean winter wheat cultivars and lines. Cookie baking parameters, except for cookie diameter and top grain score, were influenced by locations and years. Chokwang, Suwon 274, Suwon 275, Suwon 277 and Urimil showed larger cookie diameter and excellent top grain score compared to the other Korean winter wheat cultivars and lines. Among the flour characteristics, protein content, damaged starch content, alkaline water retention capacity and flour swelling volume showed high positive correlation coefficients with cookie baking parameters. Friabilin-present lines showed larger cookie diameter, suitable surface structure of cookie and softer snapping force than the friabilin-absent lines.

• 한국공작기계학회논문집
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• 제14권5호
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• pp.49-54
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• 2005

An experimental Investigation was performed to study the characteristics of Electro-Rheological fluid flow in a horizontal rectangular tube with or without D.C electric field control. First, the microscopic behavior of the ER suspension structure between rectangular tube brass electrodes for the stationary ER nut(i and flow of the ER fluid was investigated by flow visualization. The flow of the ER fluid between fluid rectangular tube was solved experimental using the constitutive equation for a Bingham fluid. ER fluid is made silicon oil mixed with $0.2wt\%$ starch having hydrous particles. Velocity distributions of the ER fluids were obtained by particle image velocimetry measuring those of the clusters using an image processing technique.

• 펄프종이기술
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• 제40권3호
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• pp.1-8
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• 2008

The efficiency of retention systems including compozil-G, hydrocol, compozil-S, and micropolymer under highly closed papermaking system was evaluated using contaminated white waters prepared in the laboratory. Compozil-G and compozil-S performed better in retention than hydrocol and micropolymer systems. This suggested that stronger hydrogen bonding between fiber and guar gum or starch was formed to give stronger flocculation and better retention. Especially compozil-G outperformed compozil-S in retention, and this indicated the presence of stronger interaction between guar and cellulose fibers probably due to their similarity in chemical structure. Two compozil retention systems decreased the cationic demand and COD more effectively than hydrocol and microparticle systems. In particular, compozil-G that uses guar gum was highly effective in decreasing anionic trashes at low dosage.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1306-1318
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• 2009

The filamentous ascomycete Sclerotinia sclerotiorum is well known for its ability to produce a large variety of hydrolytic enzymes. Two $\alpha$-amylases ScAmy54 and ScAmy43 predicted to play an important role in starch degradation were showed to produce specific oligosaccharides essentially maltotriose that have a considerable commercial interest. Primary structure of the two enzymes was established by N-terminal sequencing, MALDI-TOF masse spectrometry and cDNA cloning. The two proteins have the same N-terminal catalytic domain and ScAmy43 derived from ScAmy54 by truncation of 96 amino acids at the carboxyl-terminal region. Data of genomic analysis suggested that the two enzymes originated from the same $\alpha$-amylase gene and that truncation of ScAmy54 to ScAmy43 occurred probably during S. sclerotiorum cultivation. The structural gene of Scamy54 consisted of 9 exons and 8 introns, containing a single 1,500-bp open reading frame encoding 499 amino acids including a signal peptide of 21 residues. ScAmy54 exhibited high amino acid homology with other liquefying fungal $\alpha$-amylases essentially in the four conserved regions and in the putative catalytic triad. A 3D structure model of ScAmy54 and ScAmy43 was built using the 3-D structure of 2guy from A. niger as template. ScAmy54 is composed by three domains A, B, and C, including the well-known $(\beta/\alpha)_8$ barrel motif in domain A, have a typical structure of $\alpha$-amylase family, whereas ScAmy43 contained only tow domains A and B is the first fungal $\alpha$-amylase described until now with the smallest catalytic domain.

• 한국식품과학회지
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• 제41권6호
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• pp.644-651
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• 2009

수침조건에 따라 수침찹쌀과 수침액의 미생물학적 변화와 효소활성 및 구조적 특성을 살펴본 결과 수침액의 미생물상에서, 수침초기에는 젖산균이 우세하였고, 수침기간이 길어짐에 따라 미생물 균수가 급속히 증가하면서 젖산균과 Bacillus spp.이 우세 균총으로 관찰되다가 수침이 계속되면서 모든 미생물이 감소하는 경향을 보였으며 그 중에서 Bacillus spp.이 가장 많이 관찰되었다. 수침액의 $\alpha$-amylase는 수침온도와 수침기간이 증가함에 따라 지속적으로 활성이 증가하였고, protease 활성은 수침기간이 길어짐에 따라 활성이 증가한 후 감소하는 경향을 보였다. 수침 찹쌀의 $\alpha$-amylase는 수침온도가 높을수록 감소하였고, $\beta$-amylase와 glucoamylase는 수침 1일에 증가하여 수침 21일까지 일정하였다. 수침찹쌀의 미세구조를 살펴보면, 세포벽이 떨어져 나간 흔적이 보이고 다각형의 찹쌀전분입자들이 노출되면서 표면이 거칠어 보였다. 또한 찹쌀전분 입자 표면의 미세한 구멍이 수침 11일 이후 관찰되어 효소작용의 결과와 일치하는 경향을 나타냈다.

• 한국토양비료학회지
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• 제5권1호
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• pp.33-39
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• 1972

벼의 생산능력을 높이기 위하여 진흥의 곡실 생산량을 기준하여 저위 (500kg/10a 이상), 중위 (600kg/10a 이상), 고위 (700kg/10a 이상)로 구분하고 이들벼의 군락조성 및 영양상태를 조사한 결과 1. 고위수량인 경우에는 출수후 엽면적이 크고 완만하게 줄어드는데 비해 저위수량인 경우는 엽면적이 급격히 감소하였다. 2. 고위수량인 경우는 저위수량인 경우에 비해 생육초기에는 투광율이 높고 생육후기에는 낮았으며 투광율대 엽면적비도 고위수량인 경우에서 높다. 3. 순동화량(N.A.R.)은 엽면적이 증가함에 따라 감소하였으며 저위수량인 경우에 비해 고위수량인 경우가 높았다. 4. 질소흡수량은 고위수량인 경우가 저위수량인 경우에 비해 절대 흡수량이 높고 흡수속도도 전생육기간을 통해 완만하며 저위수랑인 경우는 초기 질소흡수가 많고 출수기에 질수흡수를 종결하는데 비해 고위수량인 경우는 초기 흡수가 적고 출수후에도 상당량의 질소를 흡수하였다. 5. 출수기 전분축적량이 수확기 총생산량에 대하여 저위수량인 경우 40%인 반면 고위수량인 경우에는 약 10%로서 고위수량은 출수후 전분생산량에 의존도가 크다. 6. 수량구성요수중 이차생산능력인 곡실생산능력을 가장지배하는 인자는 등숙비율이였다.

• 한국약용작물학회지
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• 제10권1호
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• pp.5-11
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• 2002

한국내 분포하는 다년생 초본인 삽주 집단의 유전적 다양도와 집단구조를 조사하기 위해 전분 전기영동으로 분석하였다. 15 대립유전자좌위당 9개 좌위에서 다형현상(60.0%)을 보였으며, 유전적 다양도는 종수준에서 0.144로 높은 반면 집단수준이 이보다 약간 낮았다. 삽주의 유전적 다양도는 대부분 집단내에 존재하였고 유사한 생활양식을 가진 다른 식물종에 비해 높았다. 그 이유로는 유성생식, 다년생, 다산 등에 기인한다. 집단간 분화는 약 13%였고 지리적 거리와 유전적 거리의 상관은 높았다(r=0.65). 그럼에도 불구하고 일부 격리된 집단은 유효집단크기를 가지지 못하여 이형접합체의 결여가 유의성을 보여 다양도가 높은 집단의 보존이 요망된다.

• 생명과학회지
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• 제16권1호
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• pp.64-70
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• 2006

한국내 주걱노루발의 유전적 다양성과 집단구조를 평가하기 위해 전분 젤 전기영동을 사용하였다. 효소내 다형현상을 나타내는 대립유전자좌위는 $57.1\%$였다. 종 수준(Hes = 0.149)과 집단 수준(Hep = 0.134)에서 유전적 다양도는 유사한 생활사를 가진 초본류의 평균값에 비해 높았다. 반면에 집단간 분화정도는 비교적 낮았다 $(G_{ST}=0.082)$. 열 두 집단내 임의교배에서 편차는 0.298이었다. 간접적으로 평가한 세대당 이주하는 개체수(Nm = 2.81)는 이 종의 한국 집단내 보통 수준을 유지하고 있었다. 고정지수 분석 결판 많은 집단과 대립유전자좌위에서 이형접합체의 결핍이 있었다. 이는 주걱노루발에서 가근의 번식능력과 한국내 조사된 주걱노루발 집단의 크기 감소에 기인한다.

• ALGAE
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• 제39권2호
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• pp.75-96
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• 2024

Rhodomonas (Cryptophyceae) and species assigned to this genus have undergone numerous taxonomic revisions. This also applies to R. marina studied here as it was originally assigned as a species of Cryptomonas and later considered a variation of R. baltica, the type species. Despite being described more than 130 years ago, R. marina still lacks a comprehensive characterization. Light and electron microscopy were employed to delineate a strain from western Greenland. The living cells were 18 ㎛ long and 9 ㎛ wide, elliptical in shape with a pointed to rounded posterior and truncated anterior in lateral view. Two sub-equal flagella emerged from a vestibulum, where also a furrow extended. In transmission electron microscopy, the furrow was associated with a tubular gullet and the pyrenoid embedded in a deeply lobed chloroplast. The chloroplast contained DNA in perforations and was surrounded by starch grains. A tubular nucleomorph was enclosed within the pyrenoid matrix. In scanning electron microscopy, the inner periplast consisted of rectangular plates with rounded edges and posteriorly these were replaced by a sheet-like structure. The water-soluble pigment was Crypto-Phycoerythrin type I (Cr-PE 545). A phylogenetic inference based on SSU rDNA confirmed the identity of strain S18 as a species of Rhodomonas as it clustered with congeners but also Rhinomonas, Storeatula, and Pyrenomonas. These genera formed a monophyletic clade separated from a diverse assemblage of other cryptophyte genera. To further explore the phylogeny of R. marina a concatenated phylogenetic analysis based on the SSU rDNA-ITS1-5.8S rDNA-ITS2-LSU rDNA region was performed but included only closely related species. The secondary structure of nuclear internal transcribed spacer 2 was predicted and compared to similar structures in related species. Using morphological and molecular signatures as diagnostic features the description of R. marina was emended.