• Title/Summary/Keyword: Cell wall

Search Result 1,899, Processing Time 0.05 seconds

The change on cell wall composition and physiological characteristic of astringent persimmon fruits by gamma irradiation (감마선 처리에 의한 떫은감 과육의 세포벽 성분 및 물성 변화)

  • Kim, Byung-Oh;Cha, Won-Seup;Ahn, Dong-Hyun;Cho, Young-Je
    • Food Science and Preservation
    • /
    • v.22 no.4
    • /
    • pp.512-519
    • /
    • 2015
  • In this study, the effects of gamma-radiation treatment on cell wall composition and physiological characteristics of astringent persimmon fruit were investigated. The soluble tannin contents of gamma-radiated samples were reduced by the radiation treatment. The hardness of the radiated fruit was decreased when compared to non-radiated fruit. Alcohol-insoluble component of the cell wall in the radiated fruit was decreased from 39.3 mg/g to 37.2 mg/g. The water-soluble content of the radiated fruit was increased from 11.4 mg/g to 13.9 mg/g. The cell wall content of the non-radiated fruit was 26.6 mg/g whereas the cell wall content of radiated fruit was decreased to 23.1 mg/g. Due to the maturation of astringent persimmon fruit by gamma-radiation, water-soluble compounds were increased whereas decreasing in cell wall compounds. The contents of lignin, pectin, and cell wall were decreased from 0.82 mg/g and 3.56 mg/g to 0.77 mg/g and 3.14 mg/g, respectively. Acid-soluble hemicellulose content was decreased by gamma-radiation, while alkali-soluble hemicellulose and cellulose contents were increased. Activities of sotening enzyme as polygalacturonase, pectinesterase and $\beta$-galactosidase existed in persimmon fruit were increased by gamma-radiation. In the sensory evaluation, gamma-radition treated persimmon showed very low astringent taste when compared to the non-radiated fruit. In hardness test, the non-radiated persimmon maintained the hardness while gamma-treated persimmon showed softened outer layer due to the condensation of tannin during radiation treatment. Therefore, gamma-radiation treatment will be used for the removal of its astringency of persimmon fruit and for enhancement of its maturation.

Growth and characterization of ZnS thin films by Hot Wall Method (Hot Wall 법에 의한 ZnS 박막의 제작과 기초적 물성연구)

  • Heo, Sung-Gon;Lee, Sang-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.05b
    • /
    • pp.108-111
    • /
    • 2000
  • The Zns thin films were deposited on non-alkali glass substrate by the Hot Wall method. The thin films grown at various evaporation cell and substrate temperature were characterized by spectrophotometer and X-ray diffraction to investigate the optical and structural characteristics. The deposition rates were increased with increasing the cell temperature, and were decreased with increasing substrate. The optical characteristics of thin films depends on the deposition rates. The band gap energies measured at room temperature with 3.4~3.5eV are smaller than the theoretical value of 3.54eV. All ZnS thin films are oriented in (111) of the principal direction of a zincblende structure.

  • PDF

A Study on the Temperature Distribution Characteristics of NAS Battery Module (NAS 전지 모듈의 온도 분포 특성에 관한 연구)

  • Heo, Doo-Sang;Yi, Chung-Seob;Jeong, Hyo-Min;Chung, Han-Shik
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.11 no.4
    • /
    • pp.1-6
    • /
    • 2012
  • This paper addresses the issue of Renewable Energy for Electricity Storage device is one of the NAS (Sodium-Sulfur) battery will be about the module. For safety reasons, not the actual battery cells using a dummy cell in the module's operating temperature setting to examine the characteristics of the insulation vacuum of the wall temperature and external temperature changes measured over time. Upper and lower boundaries of the wall vacuum insulation characteristics cotton C intervals over time, average $5^{\circ}C$, but the temperature is rising, 4C section with little temperature change did not occur. On the other hand, about $3^{\circ}C$ in section 4D, and it was confirmed that the temperature rises. Wall vacuum insulation characteristics over time to look at the experiments and measurements are described.

Photocurrent Improvement by Incorporation of Single-Wall Carbon Nanotubes in TiO2 Film of Dye-Sensitized Solar Cells

  • Jung, Kyoung-Hwa;Jang, Song-Rim;Vittal, R.;Kim, Dong-Hwan;Kim, Kang-Jin
    • Bulletin of the Korean Chemical Society
    • /
    • v.24 no.10
    • /
    • pp.1501-1504
    • /
    • 2003
  • Single-wall carbon nanotubes (SWCN) were integrated in $TiO_2$ film and the beneficial influence on the dyesensitized solar cells in terms of improved photocurrent was studied in the light of static J-V characteristics obtained both under illumination and in the dark, photocurrent transients, IPCE spectra and impedance spectra. Compared with a solar cell without SWCN, it is established that the photocurrent density of the modified cell increases at all applied potentials. The enhanced photocurrent density is correlated with the augmented concentration of electrons in the conduction band of $TiO_2$ and with increased electrical conductivity. Explanations are additionally corroborated with the help of SEM, Raman spectra and dye-desorption measurements.

Time-Lapse Video Microscopy of Wound Recovery and Reproduction in the Siphonous Green Alga Derbesia tenuissima

  • Martin, Erika;Jeremy , Pickett-Heaps;Kim, Gwang-Hoon;West, John
    • ALGAE
    • /
    • v.21 no.1
    • /
    • pp.109-124
    • /
    • 2006
  • Responses to various types of mechanically induced wounding were followed in the giant-celled Caulerpalean species, Derbesia tenuissima, using time-lapse video-microscopy. Gametophyte vesicle cells. Puncture wounding: the gametophyte cell seals the puncture in 5 min. This is followed by cycles of ruptures and sealing, ending with full recovery in 24 hrs. Cut wounding: the protoplast immediately retracts away from the wall and reforms an intact, deflated protoplast that expands to fill the original cell within 21 hrs. Crush wounding (internal). When retained within the cell wall many protoplast fragments condense, round up, and coalesce; the reconstituted protoplast expands until it attains complete recovery, filling the original cell shape in 12 hrs. Crush wounding (external). Protoplast fragments extruded from the crushed cell are more numerous and smaller taking longer to recover. Most fragments become spherical, transforming into small viable cells capable of reproduction in several days. Sporophyte filaments. Crush wounding creates many small fragments that initially condense, coalesce and then expand within the wall to restore a complete filament with normal cytoplasmic streaming within 5 hrs. Reproduction: gametophyte. Our culture isolates produce more females than males (30:1). Gametangia develop one day before discharge that occurs explosively (1/6 sec) at first morning light. The vesicle cell forms successive gametangia every 14 days. Sporophyte. Each sporangium develops on a lateral branch that becomes isolated by the creation of successive basal plugs. After cytoplasmic cleavage and differentiation the stephanokont spores are discharged. The spores settle quickly and germinate forming gametophyte cells.

Effects of Dimethylsulfoxide on the Cell Wall Regeneration and Cell Division of Protoplasts Isolated from Panax ginseng Callus (인삼 캘러스 원형질체의 세포분열과 세포벽 재생에 미치는 Dimethylsulfoxide의 효과)

  • 이석찬;이규배;박종범
    • Korean Journal of Plant Tissue Culture
    • /
    • v.27 no.6
    • /
    • pp.429-434
    • /
    • 2000
  • Isolated protoplasts from ginseng (Panax ginseng C. A. Meyer) callus tissue were cultured in modified MS media supplemented with various concentrations of dimethylsulfoxide (DMSO). The cell wall regeneration rate and cell division efficiency of the protoplasts were increased significantly by 1% DMSO treatment. However, there was no difference in the viability of protoplasts between the DMSO treatment and non-treatment. Transmission electron microscopy revealed that the microtubules were oriented in parallel manner to the plasmalemma after 3 days of culture in medium with 1% DMSO. Further, interconnected cellulose microfibrils were observed on the outer surface of the 3-day-cultured protoplasts by scanning electron microscopy These structures shown by electron microscopy were not observed in protoplasts cultured on DMSO-free media. This studies indicates that DMSO supplemented in culture media seemed to stimulate the cell wall regeneration and cell divisions of protoplasts by forming microtubule organizing centers (MTOC).

  • PDF

The Binding of Aflatoxin $B_1$ Modulates the Adhesion Properties of Lactobacillus casei KCTC 3260 to a HT29 Colon Cancer Cell Line

  • Hwang, Kwon-Tack;Lee, Won-Jae;Kim, Gye-Yeop;Lee, Shin-Kyung;Lee, Jeong-Min;Jun, Woo-Jin
    • Food Science and Biotechnology
    • /
    • v.14 no.6
    • /
    • pp.866-870
    • /
    • 2005
  • The 14 lactic acid bacteria (LAB) have been evaluated to determine the binding capacity to HT29 cell and Aflatoxin $B_1$ ($AFB_1$). The interaction of LAB to HT29 cells has been further investigated to identify the possibility of competing the binding sites with $AFB_1$. Of 14 LAB strains, Lactobacillus casei KCTC 3260 demonstrated the higher adhesiveness to HT29 and $AFB_1$ with the rate of 19.6% and 46.3%, respectively. In competitive analysis for binding sites, the adhesion of L. casei KCTC 3260 to HT29 cells was reduced with 100 nmol $AFB_1$ by 31.2%. The protoplast of L. casei KCTC 3260 showed no binding capacity to HT29 cells with increment of $AFB_1$ concentration, indicating that cell wall components might serve as a critical factor for the binding. To discriminate the major component influencing on L. casei KCTC 3260 binding to HT29 cells and $AFB_1$, four different pre-treatments (lipase, pronase E, sodium m-periodate, and urea) were employed. Of those, sodium m-periodate treatment caused the lower adhesion of L. casei KCTC 3260 to HT29 cells with the increment of $AFB_1$ concentration. These results indicated that carbohydrate moiety on the cell wall of L. casei KCTC 3260 might be the most critical component in binding to both HT29 cells and $AFB_1$.

Application of CFD-FEM Coupling Methodology to Thermal Analysis on the Large-size Marine Diesel Engine (선박용 대형 디젤 엔진 열 해석을 위한 CFD-FEM 연계 방법의 적용)

  • Kim, Han-Sang;Min, Kyoung-Doug
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.16 no.1
    • /
    • pp.64-70
    • /
    • 2008
  • Temperatures of engine head and liner depend on many factors such as spray and combustion process, coolant passage flow and engine related structures. To estimate the temperature distribution of engine structure, multi-dimensional computational fluid dynamics (CFD) codes have been mainly adopted. In this case, it is of great importance to obtain the realistic wall temperature distribution of entire engine structure. In the present work, a CFD-FEM coupling methodology was presented to address this demand. This approach was applied to a real large-size marine diesel engine. CFD combustion and coolant flow simulations were coupled to FEM temperature analysis. Wall heat flux and wall temperature data were interfaced between combustion simulation and solid component temperature analysis via translator by a commercial CFD package named FIRE by AVL. Heat transfer coefficient and surface temperature data were exchanged and mapped between coolant flow simulation and FEM temperature analysis. Results indicate that there exists the optimum cell thickness near combustion chamber wall to reasonably predict the wall heat flux during combustion period. The present study also shows that the effect of cell refining on predicting in-cylinder pressure during combustion is negligible. Hence, the basic guidance on obtaining the wall heat flux needed for the reasonable CFD-FEM coupling analysis has been established. It is expected that this coupling methodology is a robust tool for practical engine design and can be applied to further assessment of the temperature distribution of other engine components.

Changes in Chemical Composition of Sorghum as Influenced by Growth Stage and Cultivar

  • Firdous, Rafia;Gilani, Abrar Hussain
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.7
    • /
    • pp.935-940
    • /
    • 2001
  • To determine the effect of different growth stages and cultivars on the chemical composition of sorghum plant and its morphological fractions, samples of whole plant, leaf and stem of J.S-263, J.S-88 and Hegari cultivars, harvested at various growth stages were drawn for analysis. All the samples were analysed for their dry matter contents and various cell wall components such as NDF, ADF. hemicellulose, cellulose, lignin, cutin and silica. Significant increase in DM contents of whole sorghum plant, leaf and stem was observed with advancing stage of growth. The highest DM content was recorded in leaf fraction of the plant. All the cell wall constituents increased significantly in whole sorghum plant, leaf and stem as the plant matured. The maximum NDF, ADF, cellulose and lignin contents were observed in stem fraction, followed by whole plant. However, the hemicellulose, cutin and silica contents were higher in leaf fraction of the plant. The cultivars were found to have some effect on the chemical composition of whole plant, leaf and stem fractions. The results indicated that plant maturity had a much greater effect on the chemical composition of sorghum plant, whereas it was little affected by cultivars.

Effects of Cell Wall on the Transformation of Microalgae by a Digital Microfluidic System (디지털 미세유체를 이용한 미세녹조류 형질전환에서의 세포벽의 영향 분석)

  • Im, Do Jin
    • Clean Technology
    • /
    • v.21 no.2
    • /
    • pp.90-95
    • /
    • 2015
  • Digital microfluidic electroporation system was used for the transformation of microalgae and we have obtained higher transformation efficiency and viability than that of conventional method. Key parameters of electroporation such as pulse voltage, number, and duration time were systematically investigated for two different microalgal strains with and without cell wall. We have found that cell wall does not always have negative effects on the gene transformation of microalgae. Parallel processing of proposed digital microfluidic electroporation was demonstrated together with on chip culture of microalgae.