• International journal of advanced smart convergence
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• v.5 no.2
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• pp.18-23
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• 2016

Cell walls of microalgae consist of a polysaccharide and glycoprotein matrix providing the cells with a formidable defense against its environment. Anaerobic digestion (AD) of microalgae is primarily inhibited by the chemical composition of their cell walls containing biopolymers able to resist bacterial degradation. Adoption of pre-treatments such as thermal, thermal hydrolysis, ultrasound and enzymatic hydrolysis have the potential to remove these inhibitory compounds and enhance biogas yields by degrading the cell wall, and releasing the intracellular algogenic organic matter (AOM). This paper preproposal stage investigated the effect of different pre-treatments on microalgae cell wall, and their impact on the quantity of soluble biomass released in the media and thus on the digestion process yields. This Paper present optimum approach to degradation of the cell wall by ultra-sonication with practical design specification parameter for ultrasound based pretreatment system. As a result of this paper presents, a microalgae system in a wastewater treatment flowsheet for residual nutrient uptake can be justified by processing the waste biomass for energy recovery. As a conclusion on this result, Low energy harvesting technologies and pre-treatment of the algal biomass are required to improve the overall energy balance of this integrated system.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.227-235
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• 2000

Agricultural products are easily deformable its shape because of some external forces. However, these force behavior is difficult to measure quantitatively. Until now, many researches on the mechanical property was performed with various methods such as material testing, chemical analysis and non-destructive methods. In order to investigate force behavior on the cellular unit of agricultural products, electro-microscope based 3D image processing method will contribute to analysis of plant cells behavior. Before image measurement of plant cells, plant sample was cut off cross-sectioned area in a size of almost 300-400 ${\mu}$ m units using the micron thickness device, and some of preprocessing procedure was performed with fixing and dyeing. However, the wall structure of plant cell is closely neighbor each other, it is necessary to separate its boundary pixel. Therefore, image merging and shrinking algorithm was adopted to avoid disconnection. After then, boundary pixel was traced through thinning algorithm. Each image from the electro-microscope has a information of x,y position and its height along the z axis cross sectioned image plane. 3D image was constructed using the continuous image combination. Major feature was acquired from a fault image and measured area, thickness of cell wall, shape and unit cell volume. The shape of plant cell was consist of multiple facet shape. Through this measured information, it is possible to construct for structure shape of unit plant cell. This micro unit image processing techniques will contribute to the filed of agricultural mechanical property and will use to construct unit cell model of each agricultural products and information of boundary will use for finite element analysis on unit cell image.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.934-938
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• 1995

Water soluble fractions (WSF) of wheat bran treated with thermal processes such as autoclaving, microwaving and extrusion were characterized to investigate the structural response of plant cell wall to thermal and mechanical energy. From the chemical analysis and gel filtration chromatography of WSF, gelatinization of starch was found to be the primary solubilizing mechanism of wheat bran, followed by the structural disintegration of fibrous non-starch cell wall materials. It was also found that extrusion process resulted in degrading relatively higher molecular weight non-starch polysaccharides from the cell wall. GC analysis of water soluble non-starch polysaccharides indicates that the arabinoxylan residues of cell wall are the most susceptible site to thermal treatments studied. In particular, the degrading degree of cell wall of wheat bran is the most significant for extrusion accompanying both high temperature and high shear.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.358-370
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• 1994

Plant cell walls consist of a variety of chemical constituents such as cellulose, humicelluloses, pertins, lignin, glycoproteins, etc. These components are strongly linked through hydrogen , covalent, ionic and hydrophobic bondings, which thus confers the self-protection capability on plants. Some processing by-products (hulls, brans, pomaces) of cereal, fruits and vegetables are very limited in further utilization due to their compact structural rigidity. In view of the fact that the plant cell walls are essentially composed of dietary fiber components , solubilization of the strong intermolecular linkage s can contribute to increasing the soluble dietary fiber content and thus diversifying the functional and physiological role of plant cell walls as dietary fiber sources. This article reviews the chemical constituents of cereals, fruits & vegetables and brown seaweeds with reference to their intermoleuclar linkages. An particular emphasis will be placed on the solubilizing phenomena of rigid plant cell walls by extrusion and the resulting change of functional properties. It is suggested that underutilized food resources, typically exemplified by various food processing by-products and surplus seaweeds, can be successfully modified toward improved functional performance by extrusion.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.381-384
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• 2000

Relationships between biochemical phenomena and hemodynamics on human endothelial cells are very important to study the mechanism of atherosclerotic formation and development. The objective of this study is to investigate the flow phenomena around the endothelial cell model by the PIV experiment. The microscopic images of endothelial cells were acquired by a CCD camera to fabricate the shape of endothelial cell. The cell models were fabricated by using a photoforming process. Two consecutive particle images were captured by the CCD camera for the image processing. Conifer powder as the tracing particles was added to water to visualize the flow field. The cross-correlation method was applied fer the image processing of the flow visualization. Pressure and wall shear stress variations on the surfaces of the endothelial cells were calculated to investigate the effects of hemodynamic forces on the morphological changes.

• Clean Technology
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• v.21 no.2
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• pp.90-95
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• 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.

• Journal of Microbiology and Biotechnology
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• v.1 no.3
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• pp.212-219
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• 1991

Four species of yeast, Saccharomyces cerevisiae, Candida utilis, Saccharomycopsis flbuligera, and Schwanniomyces castellii were evaluated for their ability to bioconvert potato processing waste water into microbial protein and the resulting single-cell proteins were evaluated as protein sources for rainbow trout, using in vitro analyses. The studies indicated that Schwanniomyces castellii, which utilizes starch dircetly and converts it into cell mass efficiently, was suitable for the bioconversion. In the single-stage continuous bioconversion, the yield S. castellii cell mass, which contained approximately 37% protein, was 77%, at dilution rate 0.25 $h^{-1}$. Reduction of total carbohydrate was 81%. During batch fermentations, cell mass yield was about 72% and total carbohydrate reduction was 81%. Among the yeasts tested, S. castellii possessed the most fragile cell wall and had a favorable amino acid profile for salmonid fish; protein score of 86% (Met). In an in vitro pepsin digestibility test 80% digestibility (23~38% above control) was observed when cells were pre-heated in a steam bath for 30 min. Results presented should be regarded as being preliminary in nature because they were derived from single experiments.

• Plant Biotechnology Reports
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• v.5 no.1
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• pp.1-7
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• 2011

Secondary walls have recently drawn research interest as a primary source of sugars for liquid biofuel production. Secondary walls are composed of a complex mixture of the structural polymers cellulose, hemicellulose, and lignin. A matrix of hemicellulose and lignin surrounds the cellulose component of the plant's cell wall in order to protect the cell from enzymatic attacks. Such resistance, along with the variability seen in the proportions of the major components of the mixture, presents process design and operating challenges to the bioconversion of lignocellulosic biomass to fuel. Expanding bioenergy production to the commercial scale will require a significant improvement in the growth of feedstock as well as in its quality. Plant biotechnology offers an efficient means to create "targeted" changes in the chemical and physical properties of the resulting biomass through pathway-specific manipulation of metabolisms. The successful use of the genetic engineering approach largely depends on the development of two enabling tools: (1) the discovery of regulatory genes involved in key pathways that determine the quantity and quality of the biomass, and (2) utility promoters that can drive the expression of the introduced genes in a highly controlled manner spatially and/or temporally. In this review, we summarize the current understanding of the transcriptional regulatory network that controls secondary wall biosynthesis and discuss experimental approaches to developing-xylem-specific utility promoters.

• Journal of Ginseng Research
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• v.18 no.3
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• pp.187-190
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• 1994

The pith and xylem parts of fresh root that turned into inside-white during processing for red ginseng was investigated under scanning electron microscope in comparison with the sa31e position of fresh root processed into normal reddening. In the inside-white part starch storage cells remain mostly in vacancy or with small number of starch granules and with large hollow by missing cell membranes between cells. Many starch seed granules appeared on the surface of storage cell wall in the inside-white part. Fresh root sample showed better picture than dried powder.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.180-183
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• 2008

Digestion properties of 3 types of cereals, white rice, brown rice, and barley, were measured after cooking or grinding. Regardless of the processing methods, white rice showed the highest rate and the greatest extent of digestion, whereas barley showed the lowest values. During the early digestion period, cooked white rice kernels had a larger k (kinetic constant) value than uncooked white rice flour, indicating that cooking induced faster digestion than grinding. In the case of brown rice and barley, the cell wall in cooked kernels remained intact and resulted in a lower k values than those of uncooked flour. However, after 3 hr of digestion, the total digestion extent was greater for the cooked brown rice and barley than that for uncooked flours. The high content of slowly digestible starch (SDS) in cooked brown rice and barley might be due to the starch fraction which was protected by the cell wall. The resistant starch (RS) content, however, was greater for the uncooked flours than that for cooked kernels. The cooked kernels of 3 cereal samples tested showed higher glycemic index (GI) values than the uncooked flours.