• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.415-418
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• 1999

Thecodiplosis japonensis is an important insect pest in pine trees and hard to be controlled by chemical pesticides due to its characteristic life cycle. Experiments were conducted to determine the pathogenicity and growth temperature of several entomopathogenic fungi as potential microbial insectcides for T. japonensis. Beauveria bassiana SFB-SC and Paecilomyces fumosoroseus SFP-198 were highly pathogenic against T. japonensis. B. bassiana SFB-SC had also pathogenicity against a beneficial insect Bombyx mori. Growth rate and pathogenicity of P. funmosoroseus SFP-198 under 15$^{\circ}C$ was higher than those of B. bassians SFB-SC. These results indicated that P. fumosoroseus SFP-198 is a potential microbial control candidate for control of T. japonensis.

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.104-109
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• 2001

The yield of infective juveniles of Heterorhabditis bacteriophora (Tf strain) in vitro monoxenic liquid culture was improved significantly as the amount of symbiont biomass, Photorhabdus sp. strain Tf, increased. To investigate the influence of abiotic factors on the growth and biomass production of Photorhabdus sp. strain Tf, triplicate flask cu1tmes were performed. The optinal temperature and medium pH for the growth of Photorhahdus sp. strain Tf were 30$^{\circ}$C and between pH 5.5-7.3, respectively. Aeration also improved greatly growth and yield of biomass of Photorhabdus sp. strain Tf. Photorhabdus sp. strain Tf in batch fermentation showed growth-associated pattem in terms of pigment production, and the pH of culture medium rose steadily until growth stopped dUling the fermentation. Both pigment production and culture pH rise would be useful parameters indicating a reliable growth of Photorhabdus sp. strain Tf.

• The Microorganisms and Industry
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• v.12 no.2
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• pp.2-13
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• 1986

Agrobacterium tumefaciens의 연구는 유전공학 시대를 맞이하여 많은 연구자들의 커다란 주목을 끌고있다. 식물세포내에 외부 유전자를 도입시키는, 확실히 믿을 수 있는 vector로 등장된 때문이다. 원래 이세균은 식물 줄기나 뿌리에 암종을 유발시키므로서 암발성 원인 구명 연구로 흥미를 끌게 되었다. 연구결과는 암발생 예방및 치료에 목적을 둠은 덩연할 것이다. 많은 약제가 시험되었으나 별로 진전을 보지 못하던중 비 원인성인 Agrobacterium radiobacter, strain 84에 의한 생물학적 방제의 성공으로 유일한 방제법을 갖게되었다. 뒤이어 암종발생 기작도 밝혀졌다. Agrobacterium의 세계는 온통 유전공학 기술로 채워져 있다. 암종발생에서 방제원리에 이르기까지 수없이 먼 옛날부터 이미 익혀오던 DNA 조작기술이었던가\ulcorner 암종을 유발시키는 agrocin84 plasmid를 갖는 비병원성 Agrobacterium을 찾아 생물학적 방제법을 확립하였다. 그후 병원성 Agrobacterium은 이에 대하여 어떻게 살아남을 것인가\ulcorner 실로 놀라운 일이라 아니할 수 있을까\ulcorner 이 병원성 Agrobacterium은 비 병원성 Agrobacterium 속에 있는 agrocin 84 plasmid을 탈취하여 자신이 agrocin84를 생성분비하며 암종 유발을 계소하여 간다. 아니면 비병원성 Agrobacterium이 병원성 Agrobacterium에게 agrocin 84 plasmid를 넘겨주었을까\ulcorner 왜 넘겨주었을까\ulcorner 공존을 위하여서일까\ulcorner 우리의 유전공학 기술은 이것을 막아줄수 있을까\ulcorner 생물학적 방제의 재성공을 위하여 논제의 연구는 왜 필요했던가\ulcorner 그 전후를 여기에 서술해 본다.닭이며 또한 제한된 지면에서 충분히 고찰하기는 어렵다. 우리나라에서 자주 거론되는 백신 및 종류에 국한하여 그 문제점과 앞으로의 전망을 고찰해 보기로 한다.ocking electrode를 제작하여 복합고분자 전해질과의 계면저항을 측정하였다.nm (1.2921eV)는 acceptor-bound exciton 인 I1(AO,X) 이고, 964.6nm(1.2853eV)는 donor-acceptor pair(DAP) 발광, 1341.9nm (0.9239eV)는 self activated(SA)에 기인하는 광발광 봉우리로 고찰되었다.가 높을수록 방출전류가 시간에 따라 급격히 감소하였다. 각 duty비에서 방출전류의 양이 1/2로 감소하는 시점을 에미터의 수명으로 볼 때 duty비 대 에미터 수명관계를 구해 높은 duty비에서 전계방출을 시킴으로써 실제의 구동조건인 낮은 duty비에서의 수명을 단시간에 예측할 수 있었다. 단속적으로 일어난 것으로 생각된다.리 폐 관류는 정맥주입 방법에 비해 고농도의 cisplatin 투여로 인한 다른 장기에서의 농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았다이 낮았으나 통계학적 의의는 없었다[10.0%(4/40) : 8.2%(20/244), p>0.05]. 결론: 비디오흉강경술에서 재발을 낮추기 위해 수술시 폐야 전체를 관찰하여 존재하는 폐기포를 놓치지 않는 것이 중요하며, 폐기포를 확인하지 못한 경우와 이차성 자연기흉에 대해서는 흉막유착술에 더 세심한 주의가 필요하다는 것을 확인하였다. 비디오흉강경수술은 통증이 적고, 입원기간이 짧고, 사회로의 복귀가 빠르며, 고위험군에 적용할 수 있고, 무엇보다도 미용상의 이점이 크다는 면에서 자연기흉에 대해 유용한 치료방법임에는

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.589-593
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• 2002

Improvement of hygienic quality of powdered raw grains and vegetables by gamma irradiation was investigated. Five products of powdered raw grains and vegetables were collected in a local market and analysed. The total viable cell counts of Bacillus were 10$^4$~10$^{7}$ cfu/g, filamentous fungi l0$^2$~10$^3$cfu/g, coliform 10$^1$~10$^4$cfu/g, enteric bacteria on SS agar plate 10$^1$~10$^3$cfu/g. Coliform, enteric bacteria on SS agar plate and filamentous fungi were eliminated by 3 kGy of gamma irradiation. The D values of coliform, enteric bacteria on SS agar plate, Bacillus, and filamentous fungi were 0.68~0.80 kGy, 0.59~0.74 kGy, 1.84~2.18 kGy and 0.36~0.57 kGy, respectively. It was considered that optimal irradiation dose for radappertization was about 25 kGy, while 3~5 kGy of gamma irradiation was effective for radicidation.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.340-341
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• 2017

Acidovorax citrulli is a causal agent for bacterial fruit blotch on watermelon. Here, we report the complete genome sequence of A. citrulli strain KACC17005. The genome contains 5,349,924 bp with G + C contents of 68.54%, including 4,520 protein coding genes in a circular chromosome. It also possesses at least 15 genes encoding putative type III effector proteins, which may contribute to promoting virulence in susceptible hosts or triggering immune responses in resistant hosts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.450-458
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• 2017

In this study, the antimicrobial activity of black garlic pomace extract (BGPE) was examined, and its washing applicability to spinach was investigated. BGPE had antimicrobial activity against both Gram-positive (Listeria monocytogenes and Staphylococcus aureus) and Gram-negative (Escherichia coli O157:H7 and Salmonella Typhimurium) food-borne pathogens. In particular, antimicrobial activities of BGPE against Gram-positive bacteria were higher than those against Gram-negative bacteria. Spinach samples were treated with 0.5% BGPE to determine the effect of BGPE on reducing naturally existing microorganisms on the surface of spinach leaves. BGPE treatment reduced populations of total aerobic bacteria and yeast/molds in spinach by 1.23~1.35 log CFU/g and 0.82~1.12 log CFU/g during 9 days of storage, respectively, compared with those of control samples. After treatment, there were no significant differences in color quality such as Hunter L, a, and b values and total color difference (${\Delta}E$). These results clearly indicate that BGPE treatment can be useful for improving microbiological safety and maintaining color quality of spinach during storage.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.265-274
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• 2014

Gut microbiota is a group of microorganisms that resides in the intestine and serves many important functions in human health. Using 16S ribosomal RNA sequencing analysis, a wide variety of bacteria in human gastrointestinal tract has been identified along with intriguing findings that there is a different bacterial composition among individuals. Fecal microbiota transplantation (FMT) is a procedure of stool transplantation from healthy donors to patients suffering from various diseases. Specifically, FMT is able to alter the composition of gut microbiota of recipients and therefore could be an effective treatment for the patients with gastrointestinal diseases including recurrent Clostridium difficile infection, inflammatory bowel disease, and irritable bowel syndrome. Here we review a list of human diseases related to gut microbiota disturbance and the case studies of FMT. We also summarize medicines and diagnostic tools that are under development. Therefore, gut microbiota can be a next generation's biotherapy for promotion of health and treatment of chronic diseases.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.161-168
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• 2011

The purpose of this study was to evaluate microbiological contamination of fresh vegetables in Korea. Twenty types of vegetables were tested for total aerobic bacteria, coliforms, Escherichia coli, yeast and mold, and pathogenic bacteria such as Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Salmonella, E. coli O157:H7, Cronobacter sakazakii, Shigella, and Campylobacter. Levels of total aerobic bacteria and coliform on 20 vegetables were between 3.74 and 8.04 log CFU/g, and 0.16 and 5.02 log CFU/g, respectively. The highest contamination levels of total aerobic bacteria were observed on water dropwort, sprouts, mungbean sprout, and ballflower root. There was no significant difference (p>0.05) in microbial contamination levels of total aerobic count, coliform, E. coli, yeast and mold between organic and nonorganic vegetables. When isolation methods using selective agars were applied, L. monocytogenes, B. cereus, Salmonella and Campylobacter were isolated from some fresh vegetable samples. Results of API kit tests showed that L. monocytogenes was identified on Chinese cabbage, cucumber, soybean sprouts, and iceberg lettuce while Salmonella was identified on Korean leek. Furthermore, Campylobacter jejuni was also identified in more than 50 of the 100 samples. However, when positive samples from API kit were tested for real-time PCR or 16S rRNA sequencing method, only B. cereus from perilla leaf, carrot, water dropwort, and sprouts showed positive results. These results indicate that selective agar and API kit detection methods might result in false positive results for some pathogens. Therefore, studies need to improve isolation or confirmation methods for such pathogens.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.103-107
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• 2004

This study was carried out to investigate the growth of pathogenic germ in fermented pork with Korean traditional seasonings. The samples, outside muscle of pork ham were cut by the shape of cube (7${\times}$12${\times}$2cm) and seasoned with five Korean traditional seasonings such as garlic paste (Tl), pickled Kimchi (T2), pickled Kimchi juice (T3), soybean paste (T4), red pepper paste (T5). The rate of meat to seasonings was same. The seasoned samples were fermented at -1${\pm}$1$^{\circ}C$ for 28 days. Microbial pathogens such as Escherichia coli O157, Listeria monocytogenes, Salmonella enteritidis were not detected in all paste and samples. When 1.5${\times}$l0$^3$ CFU/$\textrm{cm}^2$ of Escherichia coli O157 was inoculated, the numbers were slightly increased to 10$^3$-10$^4$ CFU/$\textrm{cm}^2$ at 3 days and gradually decreased to the level of inoculation at 18 days in all samples. In the inoculation with Listeria monocytogenes (8${\times}$l0$^4$ CFU/$\textrm{cm}^2$), the numbers were below 10$^3$ CFU/$\textrm{cm}^2$ during 28 days in T3 and T4, while they were increased to 10$\^$6/ CFU/$\textrm{cm}^2$ in Tl and T2 at 3 and 13 days respectively, and decreased to 10$^4$ CFU/$\textrm{cm}^2$. In the inoculation with Salmonella enteritidis (3${\times}$l0$^4$ CFU/$\textrm{cm}^2$), the numbers increased to 10$\^$5/ CFU/$\textrm{cm}^2$ at 18 days, but they were rapidly decreased to the level of initial inoculation at 23 days.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.346-349
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• 2005

병원성미생물을 분리${\cdot}$동정하는 방법으로 선택배지를 이용하는 검사방법은 4${\sim}$7일의 시간이 소요되는 단점이 있으며, 기존의 PCR방법은 대부분 단일 병원성 미생물만을 검출할 수 있는 반면 본 연구에서 사용된 시스템은 6종류의 세균성 식중독균을 한 번의 분석으로 확인할 수 있었기 때문에 비용과 분석시간을 대폭 절감하는 효과가 있었다. Fig. 1은 6종류의 세균성 식중독균이 혼합된 시료에 각각의 단일 프라이머를 이용하여 특이성을 확인한 결과이며, Fig. 2는 멀티플렉스 프라이머를 이용하여 각각의 세균성 식중독균 열 추출 시료에 대한 특이성을 확인한 결과이다. PCR 산물들이 사다리(ladder) 형태로 증폭됨으로써 동시에 6종류의 세균성 식중독균을 용이하게 확인할 수 있었다(Lane 1${\sim}$Lane 6). 또한 3종류의 세균성 식중독균이 혼합된 열 추출시료에서도 특이적인 PCR 증폭 산물들을 탐지할 수 있었다(Lane 10 & Lane 11).