• Applied Microscopy
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• v.42 no.4
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• pp.194-199
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• 2012

The anatomy and morphology of seeds from 10 Hawaiian Portulaca taxa were examined to explore patterns of variation among the taxa, and to evaluate their phylogenetic relationships. Features of seeds were assessed employing microtechnique procedures, statistical analysis, and scanning electron microscopy (SEM). Anatomically, the orientation of embryo was consistent across taxa, and all seeds examined had central nutritive tissue and integuments comprising the peripheral embryo. Seeds were generally small, circular to ovoid in shape, and either smooth or rough-surfaced, with tubercules. Variation in seed size was noted, although minimal within small seeded group. The size of seeds ranged from 0.50~1.26 mm in length, and 0.55~1.34 mm in width, with similar weights. Seeds were distinguished by the sculpture and arrangement of the testa epidermis and the way in which their stellulate-tessellate cells uniquely fit together. Using a multiple range test (ANOVA), two groups were established by seed characteristics. The SEM also demonstrated morphological differences in testa sculpturing. The results obtained confirm the usefulness of seed characteristics in the identification of the species examined, and furthermore, allow for the separation of the Hawaiian Portulaca into two groups.

• Mycobiology
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• v.29 no.2
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• pp.104-106
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• 2001

Alternaria cassiae Jurair & Khan was recorded on seeds of sickle senna(Cassia tora L.). Seed infection ranged from $25{\sim}45%$ in two samples. Developing roots and shoots turn brown and died in case of severe infection. Detailed descriptions were given on the habit characters of the fungus and on the morphology of conidiophores and condia. This is the first report of A. cassiae on seeds of Cassia.

• Korean Journal of Plant Taxonomy
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• v.41 no.1
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• pp.35-46
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• 2011

The seed morphology of 22 taxa (12 genera) of Solanaceae in Korea was studied by stereo and scanning electron microscopy, and a detailed description of seed morphological features for all examined taxa is provided. The color of the seed is yellow to black, and the shape is reniform to circular. Its size is 0.56-4.29 mm in length and 0.38-3.20 mm in width. The largest sample was found in Datural metel, while the smallest was in Petunia hybrida. Three different surface types (verrucate, verrucate-reticulate, and reticulate) were recognized in the studied taxa. The top of the anticlinal wall produces appendages known as 'fibrils'. This projection of anticlinal wall was found to be specific to the genus Solanum (S. japonense, S. lyratum, and S. lycopersicum). The morphological features (seed shape, size, color, hilum shape, surface type, and fibrils) of the family Solanaceae in Korea are described and their systematic implications are briefly discussed.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2283-2287
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• 2007

Amyloid fibril formation of amyloid β/A4 protein (Aβ) is critical to understand the pathological mechanism of Alzheimer's disease and develop controlling strategy toward the neurodegenerative disease. For this purpose, dequalinium (DQ) has been employed as a specific modifier for Aβ aggregation and its subsequent cytotoxicity. In the presence of DQ, the final thioflavin-T binding fluorescence of Aβ aggregates decreased significantly. It was the altered morphology of Aβ aggregates in a form of the bundles of the fibrils, distinctive from normal single-stranded amyloid fibrils, and the resulting reduced β-sheet content that were responsible for the decreased fluorescence. The morphological transition of Aβ aggregates assessed with atomic force microscope indicated that the bundle structure observed with DQ appeared to be resulted from the initial multimeric seed structure rather than lateral association of preformed single-stranded fibrils. Investigation of the seeding effect of the DQ-induced Aβ aggregates clearly demonstrated that the seed structure has determined the final morphology of Aβ aggregates as well as the aggregative kinetics by shortening the lag phase. In addition, the cytotoxicity was also varied depending on the final morphology of the aggregates. Taken together, DQ has been considered to be a useful chemical probe to control the cytotoxicity of the amyloid fibrils by influencing the seed structures which turned out to be central to develop therapeutic strategy by inducing the amyloid fibrils in different shapes with varied toxicities.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5719-5723
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• 2013

Pharmacological and preventive properties of Petroselinum sativum seed extracts are well known, but the anticancer activity of alcoholic extracts and oil of Petroselinum sativum seeds on human breast cancer cells have not been explored so far. Therefore, the present study was designed to investigate the cytotoxic activities of these extracts against MCF-7 cells. Cells were exposed to 10 to $1000{\mu}g/ml$ of alcoholic seed extract (PSA) and seed oil (PSO) of Petroselinum sativum for 24 h. Post-treatment, percent cell viability was studied by 3-(4, 5-dimethylthiazol-2yl)-2, 5-biphenyl tetrazolium bromide (MTT) and neutral red uptake (NRU) assays, and cellular morphology by phase contrast inverted microscopy. The results showed that PSA and PSO significantly reduced cell viability, and altered the cellular morphology of MCF-7 cells in a concentration dependent manner. Concentrations of $50{\mu}g/ml$ and above of PSA and $100{\mu}g/ml$ and above of PSO were found to be cytotoxic in MCF-7 cells. Cell viability at 50, 100, 250, 500 and $1000{\mu}g/ml$ of PSA was recorded as 81%, 57%, 33%, 8% and 5%, respectively, whereas at 100, 250, 500, and $1000{\mu}g/ml$ of PSO values were 90%, 78%, 62%, and 8%, respectively by MTT assay. MCF-7 cells exposed to 250, 500 and $1000{\mu}g/ml$ of PSA and PSO lost their typical morphology and appeared smaller in size. The data revealed that the treatment with PSA and PSO of Petroselinum sativum induced cell death in MCF-7 cells.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1829-1832
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• 2013

In the present study, investigations were carried out to screen the anticancer activities of fenugreek seed oil against cancer cell lines (HEp-2, MCF-7, WISH cells), and a normal cell line (Vero cells). Cytotoxicity was assessed with MTT and NRU assays, and cellular morphological alterations were studied using phase contrast light microscopy. All cells were exposed toi 10-1000 ${\mu}g/ml$ of fenugreek seed oil for 24 h. The results show that fenugreek seed oil significantly reduced the cell viability, and altered the cellular morphology in a dose dependent manner. Among the cell lines, HEp-2 cells showed the highest decrease in cell viability, followed by MCF-7, WISH, and Vero cells by MTT and NRU assays. Cell viability at 1000 ${\mu}g/ml$ was recorded as 55% in HEp-2 cells, 67% in MCF-7 cells, 75% in WISH cells, and 86% in Vero cells. The present study provides preliminary screening data for fenugreek seed oil pointing to potent cytotoxicity against cancer cells.

• Journal of Powder Materials
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• v.23 no.4
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• pp.270-275
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• 2016

We report on an all-solution-processed hydrothermal method to control the morphology of ZnO nanostructures on Si substrates from three-dimensional hemispherical structures to two-dimensional thin film layers, by controlling the seed layer and the molar contents of surfactants during their primary growth. The size and the density of the seed layer, which is composed of ZnO nanodots, change with variation in the solute concentration. The ZnO nanodots act as heterogeneous nucleation sites for the main ZnO nanostructures. When the seed layer concentration is increased, the ZnO nanostructures change from a hemispherical shape to a thin film structure, formed by densely packed ZnO hemispheres. In addition, the morphology of the ZnO layer is systematically controlled by using trisodium citrate, which acts as a surfactant to enhance the lateral growth of ZnO crystals rather than a preferential one-dimensional growth along the c-direction. X-ray diffraction and energy dispersive X-ray spectroscopy results reveal that the ZnO structure is wurtzite and did not incorporate any impurities from the surfactants used in this study.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.281.1-281.1
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• 2013

Shape control of gold nanocrystal is still one of the most important challenges remaining to achieve geometry dependent properties. Thus far, several strategies have been developed to control the shape of nanoparticles, such as adding capping agents and diverse additives or adjusting the temperature and pH. Here, we used an already established seed-mediated method that allowed us to focus on controlling the growth stage. Cetyltrimethylammonium bromide (CTAB) and ascorbic acid (AA) were used as the ligand and the reducing agent, respectively, without using any additional additives during the growth stage. We investigated how the relative ratio of CTAB and AA concentrations could be a major determinant of nanoparticle shape over a wide concentration range of CTAB and AA. As a result, a morphology diagram was constructed experimentally that covered the growth conditions of rods, cuboctahedra, cubes, and rhombic dodecahedra. The trends in the morphology diagram emphasize the importance of the interplay between CTAB and AA. Furthermore, high-index faceted gold nanocrystal was obtained by two step seeded growth. Already synthesized cubic particles developed into hexoctahedral nanocrystal consisting of 48 identical {321} facets, which indicates that the growth of gold nanocrystal is affected by initial morphology of seed particles. The hexoctahedral gold nanoparticles can be used in catalysis and optical applications which exploiting their unique geometry. Our research can provide useful guidelines for designing various facetted geometries.

• The Korean Journal of Ceramics
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• v.2 no.4
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• pp.221-225
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• 1996

In diamond synthesis by metal film growth method under high pressure and high temperature, the nucleation and growth of diamond was observed dependent on the carbon source variation from graphite powder to the heat treated powders of lamp black carbon. At the low driving force condition near equilibrium pressure and temperature line, nucleation of diamond did not occur but growth of seed diamond appeared in the synthesis from lamp black carbon while both nucleation and growth of diamond took place in the synthesis from graphite. Growth morphology change of diamond occurred from cubo-octahedron to octahedron in the synthesis from graphite but very irregular growth of seed diamond occurred in the synthesis from lamp block carbon. Lamp black carbon transformed to recrystallized graphite first and very nucleation of diamond was observed on the recrystallized graphite surface. Growth morphology of diamond on the recrystallized graphite was clear cubo-octahedron even at higher pressure departure condition from equilibrium pressure and temperature line.

• Macromolecular Research
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• v.17 no.4
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• pp.250-258
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• 2009

One-step seeded polymerization was used to prepare $7{\sim}10{\mu}m$ of crosslinked monodisperse spheres with four crosslinking agents using $4.68{\mu}m$ poly(methyl methacrylate)(PMMA) seed particles in aqueous-alcoholic media in the absence of the swelling process. The crosslinking agents used were ethylene glycol dimethacrylate(EGDMA), allyl methacrylate(AMA), 1,6-hexanediol diacrylate(HDDA) and trimethylolpropane trimethacrylate(TMPTMA). The effects of the type and concentration of the crosslinking agents on the swelling, pore size, thermal property of the networks and morphology of the particles were studied. The chemical structures and concentrations of the crosslinking agents affected both the swelling ratio and the porosity of the networks. In addition, the chemistry of the reactive vinyl group and chain length of the crosslinking agents affected the stability of the monodisperse particles of the ultimate morphology.