• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.145-146
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• 2000

The presence of cross-reacting muramidase in Lactobacillus delbrueckii ssp. bulgaricus ULl2 was shown by using monoclonal antibodies raised against an muramidase-2 of Enterococcus hirae ATCC 9790. The separation of protein by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Western immunoblot confirmed the presence of one cross-reacting band in Enterococcus hirae with an estimated molecular mass of 80 kDa, L. bulgaricus cultured cells harvested after 4 and 12 h were submitted to different autolysin releasing procedures and the liberated products were allowed to cross-react with muramidase-2 antibodies in order to estimate the efficiency of each treatment. Although the cultured cells harvested after 4 h yielded only a slight immune-reaction in Western immunoblots against these enzyme monoclonal antibodies, a strong signal was observed for the cell walls obtained from the same experimental conditions and treated with Triton X-100 surfactant. The same phenomenon was also observed by light fluorescence microscopy. Immune-labelling followed by optical and electron microscopy have shown that the muramidase-2 of L. bulgaricus ULl2 was essentially localized in the innermost part of the cell wall.(omitted)

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.91-99
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• 2006

This study was conducted to determine the influence of postharvest dipping treatment with aminoethoxyvinylglycine (AVG) on ethylene production and composition of non-cellulosic neutral sugars in cell walls of 'Tsugaru' apple fruits during storage. Fruits were harvested on August 20, soaked in AVG 50 and 75 $mg L^{-1}$ solution for 5 minutes, and stored in cold storage chamber at $0{\pm}1^{\circ}C$ for 60 days. Fruit quality factor, ethylene productions, and cell wall component changes were investigated at 20 days interval. As a result, the fruit firmness and acid content were much higher in AVG treated fruits than those of untreated one during 60 days of cold storage. Ethylene production of AVG treated fruits was reduced to the level of 1/10 compared with untreated one. As to the change of non-cellulosic neutral sugars in the cell walls of 'Tsu- garu' fruits, the major sugar was arabinose and galactose in water, CDTA and $Na_2CO_3$ soluble fractions. The content of arabinose and galactose in untreated fruits increased as the softening of fruits was in progress, but the fruits treated with AVG showed a little change during storage, so it is predicted that these two cell wall compositional sugars were not solubilized by the treatment of AVG. Accordingly, the marketability of 'Tsu- garu' fruits could remarkably increase when soaking the fruits in AVG solution after harvest.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.740-744
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• 2005

Bifidobacterium has been previously shown to potentiate immune function, which was mediated through the stimulation of cytokine production by macrophage. This study was performed to further characterize the effective component of Bifidobacterium by measuring the level of interleukin (IL)-6 cytokine using the RAW 264.7 murine cell line as a macrophage model. RAW 264.7 cells were cultured for 24 h in the presence of whole cells (WCs), cell walls (CWs), and cell-free extracts (CFEs) from various strains of Bifidobacterium and other lactic acid bacteria at various concentrations. The most effective component was different depending on the strains and the concentrations used. When tested with each cell fraction from Bifidobacterium sp. BGN4, heat treatment of the cell fractions lowered the production of IL-6. Synergistic effect was obtained, especially when CWs and CFEs were combined. Sonicated WCs stimulated IL-6 production more than intact WCs. The in vitro approaches employed here should be useful in further characterization of the effects of Bifidobacterium on gastrointestinal and systemic immunity.

• Journal of Plant Biology
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• v.30 no.1
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• pp.21-30
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• 1987

The effects of abscisic acid(ABA) spraying for 12 weeks on the stomatal types and frequencies of O. malacophyllus leaves were summarized as follows. ABA inhibited the growth of O. malacophyllus. The prominent effect of ABA on the epidermal structure was the promotion of senescence such as thickness of cell walls, smooth sinuosity of cell walls, and large size of epidermal cells. The stomatal frequency was decreased to 23% by 10$\mu\textrm{g}$ ml-1 ABA and to 48% by 100$\mu\textrm{g}$ml-1, and also the stomatal size was more or less smaller than that of control. The developing secondary stomatal mother cell was not found in both 10 and 100$\mu\textrm{g}$ml-1ABA, but the arrested secondary stomatal mother cell was rarely found in 10$\mu\textrm{g}$ ml-1 ABA. The formation of normal stomatal types such as helico-eumesogenous and aniso-eumesogenous was found in both 10 and 100 $\mu\textrm{g}$ ml-1 ABA asin well as control. Also nine abnormal stomatal types were found, and the frequencies were promoted to 6% by 10 $\mu\textrm{g}$ ml-1 ABA and to 17% by 100 $\mu\textrm{g}$ ml-1 ABA. Among these abnomal stomata, four types such as aborted stomata, single-aborted guard cells, arrested stomata, and modified stomatal complexes were found in control as well as in 10 and 100 $\mu\textrm{g}$ ml-1 ABA, but five types such as wrenched stomata, unequal stomata, wavy guard cells, guard cells overlapped by guard cells, and dissolved cell wall stomata were found in both 10 and 100 $\mu\textrm{g}$ ml-1ABA. The modified stomata complexes were abnormal stomatal types which were newly found and also were varied in types.

• Journal of Food Hygiene and Safety
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• v.10 no.3
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• pp.147-153
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• 1995

The ethanol extract from the root bark of Morus alba showed the strongest antimicrobial activity on the growth of almost all the tested microorganisms which were food-borne pathogens and food-related microorganisms. Therefore, fatty acid composition, amino acid composition and shape change of microorganisms treated with the ethanol extract from the root bark of Morus alba were examined. In effects of treatment with the ethanol extract on the fatty acid compositions of B. subtilis, S. aureus and E. coli, fatty aicd compositions such as hexadecanoic acid (16:0) and octadecanoic acid (18:2) of the tested strains were increased but pentadecanoic acid (15:0) heptadecanoic acid (17:0) and acid (16:1) and octadecenoic acid (18:1) of E. coli were decreased. The ethanol extract did not significantly affect the aminn acid composition of the tested strains. Transmission electron micrographs of microorgani는 treated with the ethanol extract exhibited morphological changes that irregularly contracted cell surface in S. aureus and destructed cell walls in B. subtilis and E. coli.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.134.1-134
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• 2003

The purpose of this study was to investigate the release of p-hydroxybenzoic acid and other compounds from cell wall materials(CWM) and their cellulose fraction from carrot with chemical and enzymatic hydrolysis. To investigate this effect on cell wall chemistry of carrot, alcohol insoluble residue(AIR) of CWM were prepared and were extracted sequentially with water, imidazole, CDTA(-1, -2), Na$_2$CO$_3$(-1, -2), KOH(0.5, 1.0 and 4M), to leave a residue. These were analysed for their carbohydrate and phenolic acids composition. Arabinose and galactose were the main noncellulosic sugars. Phenolics esterified to cell walls in carrot were found to consist primarily of p-hydroxybenzoic acid with minor contribution from vanillin, ferulic acid and p-hydroxybenzaldehyde. p-Hydroxybenzoic acid was quite strongly bound to the cell wall. The contents of p-hydroxybenzoic acid in 0.5M KOH, Na$_2$CO$_3$-2, IM KOH, and ${\alpha}$-cellulose were 2,097, 1,360, 1,140, and 717 $\mu\textrm{g}$/g AIR from CWM, respectively. Alkali labile unknown aromatic compound(C$\sub$7/H$\sub$10/O$_2$) was found in ${\alpha}$ -cellulose hydrolyzate digested with driselase and cellulase. This compound was also found in hydrolyzate of 2 M trifluoroacetic acid at 120$^{\circ}C$ for 2 hours. Driselase treatment solubilized only 46.6 $\mu\textrm{g}$/g of the p-hydroxybenzoic acid from carrot AIR. These results indicate that p-hydroxybenzoic acid was associated with neutral polysaccharides, long chain galactose and branched arabinan from graded alcohol precipitation.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.157-160
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• 2003

Honeycomb sandwich composite structures have been widely used in aircraft and military industry because of light weight and high stiffness. Accurate mechanical properties of honeycomb materials are needed for analysis of sandwich composites. In this study, theoretical formula for elastic modulus of honeycomb materials was established considering bending and axial deformations of their walls. Finite-element analysis results were compared with theoretical ones of the longitudinal and transverse moduli of honeycomb materials. Consequently, the mechanical properties of honeycomb materials could be analytically predicted.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.04a
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• pp.116-116
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• 2005

• Molecules and Cells
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• v.20 no.1
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• pp.119-126
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• 2005

${\alpha}$-Expansins are bound to the cell wall of plants and can be solubilized with an extraction buffer containing 1 M NaCl. Localization of ${\alpha}$-expansins in the cell wall was confirmed by immunogold labeling and electron microscopy. The subcellular localization of vegetative ${\beta}$-expansins has not yet been studied. Using antibodies specific for OsEXPB3, a vegetative ${\beta}$-expansin of rice (Oryza sativa L.), we found that OsEXPB3 is tightly bound to the cell wall and, unlike ${\alpha}$-expansins, cannot be solubilized with extraction buffer containing 1 M NaCl. OsEXPB3 protein could only be extracted with buffer containing SDS. The subcellular localization of the OsEXPB3 protein was confirmed by immunogold labeling and electron microscopy. Gold particles were mainly distributed over the primary cell walls. Immunohistochemistry showed that OsEXPB3 is present in all regions of the coleoptile and root tissues tested.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.119.1-119
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• 2003

The glyoxysomal nature of microbodies was determined in Botryosphaeria dothidea hyphae based on morphology and in situ enzyme characteristics by transmission electron microscopy and cytochemistry. Bound by a single membrane, microbodies had a homogeneous matrix and varied in size ranging from 200 to 400 m in diameter. Microbodies had crystalline inclusion(s) which consisted of parallel arrays of fine tubules in their matrices. Microbodies and lipid globules were frequently placed in close association with each other, forming microbody-lipid globule complexes in hyphae. The cytochemical activities of catalase and malate synthase were localized in matrices of microbodies, showing intense electron-density of the organelle. In addition, the immunogold labeling detected the presence of catalase in multivesicular bodies and hyphal cell walls as well as in matrices and crystalline inclusions of microbodies, supporting the enzyme secretion through cell walls. Meanwhile, isocitrate Iyase was localized only in matrices of microbodies. These results suggest that microbodies, particularly complexed with lipid globules, in the fungal hyphae are functionally defined as glyoxysomes, where glyoxysomal enzymes are biochemically active for the glyoxylate cycle to be a metabolic pathway in gluconeogenesis. (Mycology and Fugus Diseases)