• Korean Journal of Microbiology
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• v.45 no.3
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• pp.275-280
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• 2009

The optimal medium compositions for the production of bacterial cellulose (BC) by a Acetobacter sp. V6, which was isolated from the traditionally fermented vinegar in Korea, were investigated in static cultures. The optimum medium compositions for BC production were 3% glucose, 3% soytone, 0.8% $K_2HPO_4$, and 0.4% ethanol, respectively. Adding $NaH_2PO_4$ or $KH_2PO_4$ had not shown the increase in BC production. Under the optimum medium compositions, the highest BC production was 44.67 g/$m^2$ in 8 days and the thickness of BC pellicle was about 1 cm. Structural properties of BC produced in the optimal medium were studied using Fourier-transform infrared spectroscopy and X-ray diffractometer. BC from the optimal medium was found to be of cellulose type I, the same as typical native cellulose. No difference in the compositions between bacterial and plant celluloses, but BC showed unique micro-network structure and high crystallinity (82%).

• The Journal of the Korean Society for Microbiology
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• v.35 no.5_6
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• pp.372-372
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• 2000

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.1
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• pp.113-118
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• 2009

We investigated the structure of bacterial communities present in livestock manure-based composting processes and evaluated the bacterial succession during the composting processes. Compost samples were derived separately from swine manure, dairy manure and sewage sludge. The structure of the bacterial community was analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) using universal eubacterial primers. The genus Bacillus and related genera were mainly detected following the thermophilic composting phase of swine and dairy manure composts, and the members of the phylum Bacteroidetes were mainly detected in the cattle manure waste-based and sewage sludge compost. We recovered and sequenced limited number of the bands; however, the PCR-DGGE analysis showed that predominant diversities during the composting processes were markedly changed. Although PCR-DGGE analysis revealed the presence of different phyla in the early stages of composting, the members of the phylum Firmicutes and Bacteroidetes were observed to be one of the predominant phyla after the thermophilic phase.

• Journal of fish pathology
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• v.6 no.2
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• pp.197-204
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• 1993

Flounder culture has been developed mainly in the western parts of japan, and, to date, following six bacterial diseases have been reported. Bacterial white enteritis occurs in 16 to 30-day-old flounder larvae and often causes mass mortality in seed production. Bacterium named Vibrio sp. INFL invades and multiplies in the mucosae of posterier part of intestine, and causes desquamative enteritis. Gliding bacterial disease occurs mostly in juvenile stage and in spring to summer. Diseased signs are partial discoloration and erosion of skin and fins. Histologically, epidermis are removed, and the causative bacterium, Flexibacter maritimus, multiplies on the surface of demis and invades into the muscular tissue. Vibriosis caused by Vibrio anguillarum and related organisum is one of the well-known diseases among marine fish. Outbreaks of the disease in flounder culture are relatively few, but mass mortalities in fingerlings due to the disease were reported. An outbreak of nocardiosis in the autumn of 1984 has been reported, but since then the disease scarcely occurred. The disease is characterized by formation of abscesses under the skin and white nodes in the gill, heart, spleen and kidney. Streptococcicosis occurs frequently in recent years. Beta-hemolytic streptococcus is the causative bacterium, which possesses the same biochemical and serological characteristics as $\beta$-streptococci isolated from some marine and freshwater fish, and is seemed to related to Streptococcus iniae. Edwardsiellosis is the disease that causes most damage in flounder culture in Japan. Characteristic symptoms are swelling of abdomen and intestinal protrusion from the anus due to accumulation of ascites. Edwardsiella tarda, a well-known pathogen of freshwater fish, is the causative bacterium of the disease.

• Research in Plant Disease
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• v.20 no.3
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• pp.182-188
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• 2014

Because bacterial isolates from only a few genera have been developed commercially as biopesticides, discovery and characterization of novel bacterial strains will be a key to market expansion. Our previous screen using plant bioassays identified 24 novel biocontrol isolates representing 12 different genera. In this study, we characterized the 3 isolates showing the best biocontrol activities. The isolates were Pantoea dispersa WCU35, Proteus myxofaciens WCU244, and Exiguobacterium acetylicum WCU292 based on 16S rRNA sequence analysis. The isolates showed differential production of extracellular enzymes, antimicrobial activity against various fungal or bacterial plant pathogens, and induced systemic resistance activity against tomato gray mold disease caused by Botrytis cinerea. E. acetylicum WCU292 lacked strong in vitro antimicrobial activity against plant pathogens, but induced systemic resistance against tomato gray mold disease. These results confirm that the trait of biological control is found in a wide variety of bacterial genera.

• Korean Journal of Veterinary Research
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• v.56 no.2
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• pp.57-66
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• 2016

The gut epithelial barrier, which is composed of the mucosal layer and the intestinal epithelium, has multiple defense mechanisms and interconnected regulatory mechanisms against enteric microbial pathogens. However, many bacterial pathogens have highly evolved infectious stratagems that manipulate mucin production, epithelial cell-cell junctions, cell death, and cell turnover to promote their replication and pathogenicity in the gut epithelial barrier. In this review, we focus on current knowledge about how bacterial pathogens regulate mucin levels to circumvent the epithelial mucus barrier and target cell-cell junctions to invade deeper tissues and increase their colonization. We also describe how bacterial pathogens manipulate various modes of epithelial cell death to facilitate bacterial dissemination and virulence effects. Finally, we discuss recent investigating how bacterial pathogens regulate epithelial cell turnover and intestinal stem cell populations to modulate intestinal epithelium homeostasis.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.3
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• pp.429-438
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• 2011

Mastitis is characterized by physical, chemical and bacteriological changes in the milk and pathological changes in the glandular tissue of the udder and affects the quality and quantity of milk. The bacterial contamination of milk from the affected cows render it unfit for human consumption and provides a mechanism of spread of diseases like tuberculosis, sore-throat, Q-fever, brucellosis, leptospirosis etc. and has zoonotic importance. Somatic cell count (SCC) is a useful predictor of intramammary infection (IMI) that includes leucocytes (75%) i.e. neutrophils, macrophages, lymphocytes, erythrocytes and epithelial cells (25%). Leucocytes increase in response to bacterial infection, tissue injury and stress. Somatic cells are protective for the animal body and fight infectious organisms. An elevated SCC in milk has a negative influence on the quality of raw milk. Subclinical mastitis is always related to low milk production, changes to milk consistency (density), reduced possibility of adequate milk processing, low protein and high risk for milk hygiene since it may even contain pathogenic organisms. This review collects and collates relevant publications on the subject.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.361-375
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• 2003

In this study, significant factors influencing on the quality and stability of fermented sausage, such as materials, processing conditions, and microbiological characteristics as well as topography during ripening, were documented. Since most fermented sausages are not heated during manufacture or before consumption, a strict control of the growth of pathogens and the selection of favourable conditions that encourage the specific growth and development of desirable microflora are particularly important. With respect to microbiological safety, hurdles, i.e., preservations(nitrite), redox potential, competitive flora, acidity(pH), and water activity($a_{w}$) are matters of importance to prevent proliferation of bacterial pathogens. Today, for ensuring the safety and quality of the final product, the application of starter cultures in combination with the proper processing is subsequently used in practice. For improving the efficiency of microbiological utility in the production of fermented sausages, the understanding of their topography is essential. The documented different points must be taken into account when HACCP systems set up for the manufacture of fermented sausages. There are continuous researches concerning desirable improvements to sausage fermentation with health enhancing properties.

• Journal of Microbiology
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• v.33 no.4
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• pp.355-362
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• 1995

Induction of antibody production in C3H/He mice by bacterial infection is regulated through the processing exerted by antigen presenting cells. From the studies with Psudomonas aeruginosa, Salmonella typhimurium, and Micrococcus luteu, lipopolysaccharides (LPS) in Gram negative bacteria, which are known to be T-cell independent B cell mitogen, seem to be the major factor stimulating immune responses via activation of macrophages. Activation of macrophage, however, does not seem to correlate with antibody production. M. luteus was easily eliminatd by activated macrophages, while the processed antigens were immediately releasedd into culture medium before presentation. Nevertheless, antigens from Gram positive bacteria, Staphylococcus aureus and Bacillus subtilis, were very very active in chemotaxis and activation of periotoneal macrophages as well as in antien presnetation, while the very nature of the antigens is not yet clearly understood.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.621-621
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• 2003

I. Objectives In order to examine the immunoresponse of host cells to Enterococcus faecalis, this in vitro study monitored the production of Interleukin-2(IL-2), Interleukin-4(IL-4) and Transforming growth $factor-{\beta}1(TGF-{\beta}1)$ in human lymphocytes. II. Materials and methods Enterococcus faecalis(ATCC29212) strains were used in this study. Strains were grown in 1-liter cultures in 85% N2-10% H2-5% $CO_2$chamber for 3 days at $37^{\circ}C$. The medium used was 3.7% brain heart infusion broth. Bacterial cells harvested from 1-liter cultures were washed, suspended in 20ml of phosphate-buffered saline(PBS). Suspensions of bacterial cells were disrupted by sonication on ice for 5 min. Protein concentration was determined by the Bicinchoninic acid(BCA) protein assay.(omitted)