• 한국응용곤충학회지
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• 제49권3호
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• pp.241-249
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• 2010

Xenorhabdus 및 Photorhabdus 두 곤충병원세균은 곤충의 아이코사노이드 생합성을 억제하여 면역작용을 저하시키는 인자로 알려지고 있다. 본 연구는 이들 세균의 배양액을 이용하여 배추좀나방(Plutella xylostella)을 방제하는 새로운 생화학농약을 개발하려 추진되었다. 두 세균 배양액의 단독 처리는 배추좀나방의 생존력에 뚜렷한 영향을 주지 않았다. 그러나 비티(Bacillus thuringiensis) 생물농약과 혼합하여 처리할 경우 비티 단독 처리에 비해 배추좀나방 4령충에 대해서 현격하게 높은 병원성 증가효과를 주었다. 배양액의 세균 활성을 조사하기 위해 이 세균 배양액을 고온 멸균 및 $0.2\;{\mu}m$ 여과 멸균 처리하였다. 이렇게 처리된 멸균 배양액은 세균이 생존했던 배양액과 차이 없이 비티 생물농약의 병원력을 상승시켰다. X. nematophila 배양액에서 유래된 세 가지 대사물질도 세균배양액과 유사한 비티 병원력 상승효과를 보였다. 야외 배추좀나방 방제 시험에서도 세균배양액은 비티 생물농약의 방제가를 상승시키는 효과를 나타냈다.

• 대한후두음성언어의학회지
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• 제32권1호
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• pp.29-34
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• 2021

Background and Objectives Tracheostomy lead to persistent bacterial colonization of the respiratory tract. Surgical site infection and restenosis by the pathogenic bacteria is the most fatal complication after open airway surgery. The aim of this study is to describe the culture results of larynx and tracheostoma in patients with tracheostomy and the preoperative, intraoperative culture results in patients underwent open airway surgery. Materials and Method A retrospective review was performed on 18 patients who underwent culture between 2017 and 2019. Results Pseudomonas or antibiotic resistance bacteria were identified in 11 patients out of 18 patients (61.1%); Ceftriaxone-resistant Streptococcus (38.9%), Pseudomonas (33.3%), Methicillin-resistant Staphylococcus aureus (16.7%), extended-spectrum β-lactamases (ESBL) producing Klebsiella pneumoniae (11.1%). Among 18 patients, 6 patients showed the different culture result between larynx and tracheostoma. In 4 out of 10 patients who underwent open airway surgery, the bacteria were not identified before surgery, but the bacteria were isolated in the intraoperative culture. In one patient, the bacteria detected intraoperatively were different from those detected before surgery. Conclusion Preoperative respiratory tract culture and usage of perioperative antibiotics according to the culture are necessary. It is crucial to verify the bacterial culture in both tracheostoma and larynx. And it should be performed immediately before open airway surgery.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1059-1064
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• 1998

Fermented beverage using lactic acid bacteria isolated from kimchi was investigated. Lactic acid bacteria KL 1, KD 6, KL 4 strains from kimchi, or obtained Lactobacillus acidophilus, Lactobacillus plantarum, Leuconostoc mesenteroides with and without yeast(Saccharomyces cerevisiae) were inoculated in fruit vegetable juice for single and mixed culture fermentation. During the fermentation by bacterial strain and yeast for 1~3 days at 30oC, various fermentation behaviors were observed. The growth rate of mixed culture of KL 1 and yeast was higher than that of single culture by KL 1 alone during the fermentation. The amount of organic acid produced by the mixed culture fermentation of KL 1 and yeast was 0.82%(3 day) or 0.58%(1 day) and with the final pH of 3.3(3 day) or 4.2(1 day). These mixed culture systems of isolated strains or other bacterial strains had almost similar results of growth rate and acid production. Among several bacterial strains, KL 1 was suitable for the mixed culture fermentation with yeast in terms of desirable fermentation behavior and organoleptical quality. The selected strain, KL 1 was identified as Leuconostoc spp. through the series of tests on carbohydrate fermentation and biochemical characteristics.

• Journal of Microbiology and Biotechnology
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• 제32권3호
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• pp.341-347
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• 2022

In this study, the bacterial community of galchi-baechu kimchi was determined using culture-based and culture-independent techniques (next generation sequencing:NGS), and showed discrepancies between results. Weissella koreensis and Pediococcus inopinatus were the dominant species according to the NGS results, while Bacillus species and P. inopinatus were dominant in the culture-dependent analysis. To identify safe starter candidates, sixty-five Bacillus strains isolated from galchi-baechu kimchi using culture-dependent methods were evaluated for their antibiotic resistance, presence of toxin genes, and hemolytic activity. Strains were then assessed for salt tolerance and protease and lipase activity. As a result, four strains-B. safensis GN5_10, B. subtilis GN5_19, B. velezensis GN5_25, and B. velezensis GT8-were selected as safe starter candidates for use in fermented foods.

• The Plant Pathology Journal
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• 제32권4호
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• pp.363-370
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• 2016

Pseudomonas syringae pv. actinidiae (Psa) causes bacterial canker disease in kiwifruit. Antibacterial activity of plant essential oils (PEOs) originating from 49 plant species were tested against Psa by a vapor diffusion and a liquid culture assays. The five PEOs from Pimenta racemosa, P. dioica, Melaleuca linariifolia, M. cajuputii, and Cinnamomum cassia efficiently inhibited Psa growth by either assays. Among their major components, estragole, eugenol, and methyl eugenol showed significant antibacterial activity by only the liquid culture assay, while cinnamaldehyde exhibited antibacterial activity by both assays. The minimum inhibitory concentrations (MICs) of estragole and cinnamaldehyde by the liquid culture assay were 1,250 and 2,500 ppm, respectively. The MIC of cinnamaldehyde by the vapor diffusion assay was 5,000 ppm. Based on the formation of clear zones or the decrease of optical density caused by these compounds, they might kill the bacterial cells and this feature might be useful for managing the bacterial canker disease in kiwifruit.

• 한국어병학회지
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• 제6권2호
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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.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.83-88
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• 2003

A cellulose-producing strain isolated from rotten apples was identified as Gluconacetobacter hansenii based on its physiological properties and the 16S rDNA complete sequencing method, and specifically named Gluconacetobacter hansenii PJK. The amount of bacterial cellulose (BC) produced by G. hansenii PJK in a shaking incubator was 1.5 times higher than that produced in a static culture. The addition of ethanol to the medium during cultivation enhanced the productivity of bacterial cellulose, plus the supplementation of 1% ethanol into the culture medium made the produced BC aggregate into a big lump and thus protected the bacterial-cellulose-producing G. hansenii PJK cells in the shear stress field from being converted into non-cellulose-producing (Cel) mutants. Cells subcultured three times in a medium containing ethanol retained their ability to produce BC without any loss in the production yield.

• 한국유기농업학회지
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• 제5권1호
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• pp.87-99
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• 1996

Cultural conditions for mass production of the antagonistic bacteria, Bacillus subtills CAP134 against pathogens causing major airborne diseases to apple tree, effect of temperature, pH, carbon and nitrogen source in the culture broth were investigated. The bacterial growth was most vigorous when the temperature and pH of the culture broth was 30~$35^{\circ}$C, and 7, respectively. As for carbon source, dextrose was best followed in order by dextrose(monosaccharides)>sucrose(disaccharides)$\geq$saccharose(di-saccharides)>starch (polysaccharides). Among different sugars, bacterial growth was favored by in the order of brown, black and white sugars, indicating that the bacterial growth might be promoted by the minor elements presented as impurities in the less purified sugars. As for nitrogen source, organic forms were better to bacterial growth than inorganic forms, that is polypeptone was best followed in order by soy sauce, soybeen milk and inoganic nitrogens. Differences in bacterial growth among different forms of inorganic nitrogen were negligible.

• 한국유기농업학회지
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• 제12권1호
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• pp.101-114
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• 2004

This study was carried out to clarify the effects of antagonistic microorganism, Bacillus sp. JC181 isolated from the greenhouse soil grown cucumber plants on the growth inhibition of plant pathogen, fusarium wilt (Fusarium oxysporum) occurred in cucumber plants in greenhouse. Antagonistic bacterial strains were isolated and were investigated into the antifungal activity of the antagonistic microorganism against fusarium wilt. Screened fourteen bacterial strains which strongly inhibited F. oxysporum were isolated from thc greenhouse soil grown cucumber plants, and the best antagonistic bacterial strain designated as JC181, was finally selected. Antagonistic bacterial strain JC181 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. JC181 showed 58.2% of antifungal activity against the plant pathogen growth of F. oxysporum. By the bacterialization of culture broth and heated filtrates of culture broth, Bacterial strain, Bacillus sp. JC181. showed 91.2% and 260% of antifungal activity against F. oxysporum, respectivrly.

• 한국유기농업학회지
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• 제6권1호
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• pp.85-98
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• 1997

Cultural conditions for mass production of the antagonistic bacteria, Bacillus subtills CAP141 against pathogens causing major airborne diseases to apple trees, effects of temperature, pH, carbon and nitrogen source in the culture broth were investigated. The bacterial growth was most vigorous when the temperature and pH of the culture broth was 30~35$^{\circ}$C and 7, respectively. As for carbon source, dextrose was best followed in order by dextrose(monosaccharide) > sucrose(disaccharide) $\geq$ saccharose (market disaccharides) > starch (polysaccharieds). Among different sugars, bacterial growth was favored by in the order of brown, black and white supars, indicating that the bacterial growth might be promoted by the minor elements presented as impurities in the less purified sugars. As for nitrogen source, organic forms were better to bacterial growth than inorganic forms, that is polypeptone was best followed in order by soy sauce, soybeen milk and inorganic nitrogens. Differences in bacterial growth among different forms of inorganic nitrogen were negligible.