• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.122-123
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• 2003

Apple stem grooving virus (ASGV) belongs to Capillovirus and infects pome fruits. Transmission mode of ASGV is known by grafting and mechanical inoculation into susceptible hosts, not by any other natural vectors. But we have observed the spread of ASGV in the field without mechanical inoculation or grafting. Transmission seems to be occurred from tree-to-tree and tree-to-susceptible herbaceous plants along but not across ditches in the field. In order to ascertain this possibility, various fungi were isolated and cultured from ASGV-infected plants and 69 isolates were characterized. By means of RNA dot-blot hybridization and PCR analysis, 3 isolates were sorted out for further studies. The isolates were identified to Tataromyces sp. and belonged to Phenicillium by morphological characteristics and molecular markers. As an experimental host, 10 kidney beans (Phaseolus vulgaris) were screened and Kyunggi-5 was selected for virus amplification and symptom development. Kyunggj-5 infected by fungi which seemed to carry ASGV showed the typical disease symptoms and viral coat protein genes were detected from all tested plants. To confirm the Koch's rule, fungi cultured from inoculation origins of kidney bean were grown on PDA media and re-inoculated to hosts. The fungi isolated from inoculation origins induced the typical disease symptoms on hosts. However virus free fungi did not induce any symptom on the experimental hosts. This bioassay showed that these typical symptoms were caused by virus, not fungi.

• The Plant Pathology Journal
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• 제27권3호
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• pp.207-224
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• 2011

Diseases caused by plant pathogenic bacteria constitute an emerging threat to global food security. Xanthomonas is a large genus of Gram-negative bacteria that cause disease in several host plants leading to considerable losses in productivity and quality of harvests. Despite the ranges of controlling techniques available, the microbiological safety of economically important crops and crop plants including fruits and vegetables continues to be a major concern to the agriculture industry. On the other hand, many of the currently available antimicrobial agents for agriculture are highly toxic, non-biodegradable and cause extended environmental pollution. Besides, the use of antibiotics has provoked an increased resistance among the bacterial pathogens and their pathovars. Thus, novel efficient and safe remedies for controlling plant bacterial diseases are necessary. There has been an increasing interest worldwide on therapeutic values of natural products such as essential oils, hence the purpose of this review is to provide an overview of the published data on the antibacterial efficacy of essential oils that could be considered suitable for application in agriculture as biocontrol measures against plant pathogenic bacteria of Xanthomonas species. The current knowledge on the use of essential oils to control Xanthomonas bacteria in vitro and in vivo models has been discussed. A brief description on the legal aspects on the use of essential oils against bacterial pathogens has also been presented. Through this review, a mode of antibacterial action of essential oils along with their chemical nature and the area for future research have been thoroughly discussed.

• Journal of Microbiology and Biotechnology
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• 제26권3호
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• pp.596-602
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• 2016

Staphylococcus aureus, like other gram-positive pathogens, has evolved a large repertoire of virulence factors as a powerful weapon to subvert the host immune system, among which alpha-hemolysin (Hla), a secreted pore-forming cytotoxin, plays a preeminent role. We observed a concentration-dependent reduction in Hla production by S. aureus in the presence of sub-inhibitory concentrations of isorhamnetin, a flavonoid from the fruits of Hippophae rhamnoides L., which has little antibacterial activity. We further evaluate the effect of isorhamnetin on the transcription of the Hla-encoding gene hla and RNAIII, an effector molecule in the agr system. Isorhamnetin significantly down-regulated RNAIII expression and subsequently inhibited hla transcription. In a co-culture of S. aureus and lung cells, topical isorhamnetin treatment protected against S. aureus-induced cell injury. Isorhamnetin may represent a leading compound for the development of anti-virulence drugs against S. aureus infections.

• 식물병연구
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• 제13권3호
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• pp.216-219
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• 2007

2005년부터 2007년까지 경남농업기술원 과수포장에서 Botryitis cinerea에 의한 매실나무 잿빛곰팡이병이 발생하였다. 병징은 과실이 담갈색을 띄며 약간 함몰되면서 시간이 경과됨에 따라 대형으로 나타난다. 심하게 감염될 경우 부패되어지고 병반부위에 회색의 곰팡이가 많이 형성된다. 분생포자는 무색, 단포자이며 난형 또는 타원형으로 크기는 $6{\sim}17{\times}4{\sim}10{\mu}m$였고, 분생포자경 위에 분생포자가 많이 형성되었다. 분생포자경은 갈색으로 격막이 있고, 폭은 $15{\sim}30{\mu}m$였다. 균사생육과 균핵형성 적온은 $20^{\circ}C$였다. 병반에서 분리한 병원균의 균학적 특징을 조사한 결과 Botrytis cinerea Persoon: Fries에 의한 매실나무 잿빛곰팡이병으로 동정되었다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.917-921
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• 2016

However, the incidence of gastric cancer (GC) has been decreased in past decades; GC is the second cause of cancer related death in the world. Evidence has illustrated that several factors including Helicobacter pylori (H. pylori) infection, host genetics, and environmental factors (smoking and particularly diet) may play a crucial role in gastric carcinogenesis. It has been demonstrated that high consumption of fresh fruits, vegetables, high level of selenium and zinc in drinking water, sufficient iron, and cholesterol protect against GC, while; smoked, pickled, and preserved foods in salt, and nitrites increase the risk of GC. Epidemiological studies have also proved that H. pylori infection and a high salt diet could independently induce atrophic gastritis and intestinal metaplasia. Recently, studies have been demonstrated that dietary factors directly influence H. pylori virulence. The use of appropriate diet could reduce levels of H. pylori colonization or virulence and prevent or delay development of peptic ulcers or gastric carcinoma. This is attractive from a number of perspectives including those of cost, treatment tolerability, and cultural acceptability. This review will describe new insights into the pathogenesis of H. pylori in relation to environmental factors, especially dietary, not only to find the developed means for preventing and treating GC, but also for understanding the role of chronic inflammation in the development of other malignancies.

• 한국응용곤충학회지
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• 제32권3호
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• pp.291-299
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• 1993

네가지 종류의 곤충 중장에 있는 주요 해독효소인 cytochrome P-450 monooxygenases의 활성을 그들의 먹이종류 및 섭식여부와 연관시켜 분석하였다. 담배나방유충을 인공사료로 사육하였을 때 전반적으로 중장의 cytochrome P-450 monooxygtenases(MFO)활성이 지방체의 경우보다 3배가량 높게 나타났다. 고추열매나 인공사료를 공급하여 사육하였을 때보다 담배잎으로 사육하였을 때 담배나방유충의 중장 MFO는 훨씬 높게 나타났으며, 흰불나방의 경우염주나무잎이 MFO활성을 가장 높게 유기했다. 담배나방, 파밤나방, 희불나방, 담배거세미나방 등의 유충들을 각각의 인공사료로 사육하였을 때 광식성이며 동시에 살충제저항성을 보유하고 있는 파밤나방의 MFO활성이 가장 높게 나타났다.

• 식물병연구
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• 제15권1호
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• pp.51-53
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• 2009

2007년 5월 상순 진주시 초전동 비닐하우스 수박 재배 포장에서 수박 흰비단병이 발생되었다. 병정은 과실 아랫 부분이 수침상으로 물러지고 부패되면서 병반부와 토양 표면에 흰색의 곰팡이가 솜털모양으로 생기고 갈색의 둥근 균핵을 많이 형성하였다. 균핵의 크기는 $1{\sim}3\;mm$이며 균사의 폭은 $4{\sim}8{\mu}m$로서 균사생육과 균핵형성 적온은 $30^{\circ}C$이었다. 균사특유의 clamp connection이 관찰되었다. 수박에서 발생한 병징과 병원균의 균학적 특징 및 병원성을 검정한 결과, 이 병을 Sclerotium rolfsii에 의한 수박 흰비단병으로 명명하고자 제안한다.

• 식물병연구
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• 제13권1호
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• pp.53-56
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• 2007

2004년과 2005년 2년간 경남농업기술원 시험포장내 울타리 부근에 재배중인 호박 과실에서 S. rolfsii에 의한 호박 흰비단병이 발생되었다. 병징은 과실이 수침상으로 물러지고 부패하면서 병반부위에 흰색의 곰팡이가 솜털처럼 생기고 갈색의 둥근 균핵을 많이 형성하였으며 크기는 1$\sim$3 mm였다. 이병과실이 지표면과 닿은 부위에도 흰색 균사와 갈색 균핵을 형성하였다 균사의 폭은 $7{\sim}8{\mu}m$이며, 균사생육적온과 균핵 형성은 30$^{\circ}C$에서 가장 좋았으며, 균사특유의 clamp connection이 관찰되었다. 호박 과실에서 발생한 병징과 균학적 특징 및 병원성을 검정한 결과, 이 병을 Sclerotium rolfsii Saccardo에 의한 호박 흰비단병으로 명명하고자 한다.

• Journal of Microbiology and Biotechnology
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• 제28권8호
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• pp.1247-1259
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• 2018

Raspberries are polyphenol-rich fruits with the potential to reduce the severity of the clinical signs associated with obesity, a phenomenon that may be related to changes in the gut microbiota. The aim of this study was to investigate the effect of raspberry supplementation on the fecal microbiota using an in vivo model of obesity. Obese diabetic db/db mice were used in this study and assigned to two experimental groups (with and without raspberry supplementation). Fecal samples were collected at the end of the supplementation period (8 weeks) and used for bacterial 16S rRNA gene profiling using a MiSeq instrument (Illumina). QIIME 1.8 was used to analyze the 16S data. Raspberry supplementation was associated with an increased abundance of Lachnospiraceae (p = 0.009), a very important group for gut health, and decreased abundances of Lactobacillus, Odoribacter, and the fiber degrader S24-7 family as well as unknown groups of Bacteroidales and Enterobacteriaceae (p < 0.05). These changes were enough to clearly differentiate bacterial communities accordingly to treatment, based on the analysis of UniFrac distance metrics. However, a predictive approach of functional profiles showed no difference between the treatment groups. Fecal metabolomic analysis provided critical information regarding the raspberry-supplemented group, whose relatively higher phytosterol concentrations may be relevant for the host health, considering the proven health benefits of these phytochemicals. Further studies are needed to investigate whether the observed differences in microbial communities (e.g., Lachnospiraceae) or metabolites relate to clinically significant differences that can prompt the use of raspberry extracts to help patients with obesity.

• 식물병연구
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• 제18권1호
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• pp.54-56
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• 2012

경상남도농업기술원 시험포장에서 S. rolfsii에 의한 수세미오이 흰비단병 증상이 발생하였다. 병징은 과실이 수침상으로 무르고 갈색으로 변하면서 썩는다. 병반부와 토양 표면에 흰색의 곰팡이가 발생하며 갈색의 작은 둥근 균핵이 형성되었다. 감자한천배지에서 균총은 흰색이고 잘 자라며 배양기간이 경과됨에 따라 갈색의 작은 둥근균핵을 많이 형성하였다. 균핵의 크기는 1-3 mm이며 균사의 폭은 4-9 ${\mu}m$였다. 균사생육과 균핵 형성 적온은 $30^{\circ}C$이었다. 균사특유의 clamp connection이 관찰되었다. 수세미오이에서 발생한 병징과 병원균의 균학적 특징, 그리고 ITS rDNA 염기서열 비교분석 결과, 이 병을 Sclerotium rolfsii Saccardo에 의한 수세미오이 흰비단병으로 명명하고자 제안한다.