• 식물병연구
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• 제25권3호
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• pp.114-123
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• 2019

Quantum Dot LED (QD LED) 조명은 소형의 크기, 좁은 대역파장, 긴 수명, 전자 시스템을 통한 제어가 용이하여 현재 시설재배에 이용되는 형광등, 할로겐램프, HID, HSP 램프의 단점을 보완할 수 있는 작물생육에 이상적인 광원으로서 잠재력을 가지고 있다. QD LED 조명을 이용하여 식물 병원성 미생물의 방제가 가능하다면 작물재배에 사용되는 인력 및 비용을 절감하고 화학적 방제제를 사용하지 않은 안전성 높은 생산물을 얻을 수 있다는 장점이 있다. 본 연구에서는 식물공장 및 온실에서 많이 재배되고 있는 상추에 큰 피해를 입히는 주요 식물 병원성 곰팡이에 대한 QD LED 조명의 영향과 생장억제효과를 확인하기 위해 시행하였다. 상추에 주로 발생하여 작물에 피해를 입히는 Rhizoctonia solani, Phytophthora drechsleri, Sclerotinia sclerotiorum, Sclerotinia minor, Botrytis cinerea, Fusarium oxysporum, Pectobacterium carotovorum, Xanthomonas campestris균을대상으로 QD LED 조명에 의한 균사생장억제 효과를 조사하였으며 처리한 6종류의 조명 중 BLUE (450 nm) 조명은 Sclerotinia sclerotiorum는 50 cm 거리에서 16.7%의 억제율을 보였으며 30 cm 거리에서 94.1%의 균사생장억제율을 보였다. S. minor는 50 cm 거리에서 80.4%, B. cinerea는 50 cm 거리에서 36.3%의 균사생장이 억제되었으며 30 cm 거리에서 S. minor와 B. cinerea는 100%의 균사생장억제율을 보였다. 15 cm 거리에서는 3종의 병원균 모두 100%의 억제율을 보였다. QD RED (M1), QD RED (M2)조명은 30 cm와 15 cm 거리에서 Sclerotinia minor와 Botrytis cinerea의 균사생장을 100% 억제했으며 Sclerotinia sclerotiorum의 경우 30 cm 거리에서 QD RED (M1)과 QD RED (M2)조명에 대해 각각 75.2%, 100%의 억제율을 보였으나 15 cm 거리에서는 각각 5.8%, 36.3%의 억제율을 보였다. 상추에 병원균을 접종하여 LED 광원 하에 생장을 확인한 결과 QD RED (M2)광원에서 S. sclerotiorum의 감염을 59.9% 억제하였고 S. minor는 BLUE (450 nm), QD RED (M1), QD RED (M2) 광원에서 59.9%의 억제율을 보였다. B. cinerea의 경우 BLUE (450 nm) 광원에서 84%의 높은 억제율을 보였다.

• Journal of Microbiology and Biotechnology
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• 제15권4호
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• pp.909-912
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• 2005

In the course of screening for selective growth inhibitors against the mycelial form of Candida albicans, we isolated a Streptomyces sp. A6792 from soils. The inhibitor was isolated from the above bacterium and identified through several spectral analyses with UV and mass spectrophotometries, and various NMR. The compound was determined to be a macrocyclic dilactone antibiotic, IKD-8344 (molecular weight: 844, molecular formula: $C_{48}H_{76}O_{12}$). The compound selectively inhibited the growth of mycelial form of C. albicans with an MIC of 6.25 ${\mu}g/ml$. It also exhibited strong inhibitory effect preferentially on the mycelial form of various Candida spp. including C. krusei, C. tropicalis, and C. lusitaniae, with MICs ranging from 1.56 to 25 ${\mu}g$/ml. Furthermore, the compound showed no significant toxicity against SPF ICR mice up to 60 mg/kg. These results suggest that IKD-8344 is a useful lead compound for the development of novel antifungal agents, based on the preferential growth inhibition against Candida spp.

• The Plant Pathology Journal
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• 제32권1호
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• pp.8-15
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• 2016

To identify a novel biopesticide controlling rice blast disease caused by Magnaporthe oryzae, 700 plant extracts were evaluated for their inhibitory effects on mycelial growth of M. oryzae. The L. foenum-graecum Herba extract showed the lowest inhibition concentration ($IC_{50}$) of $39.28{\mu}g/ml$, which is lower than the $IC_{50}$ of blasticidin S ($63.06{\mu}g/ml$), a conventional fungicide for rice blast disease. When treatments were combined, the $IC_{50}$ of blasticidin S was dramatically reduced to $10.67{\mu}g/ml$. Since ABC transporter genes are involved in fungicide resistance of many organisms, we performed RT-PCR to investigate the transcriptional changes of 40 ABC transporter family genes of M. oryzae treated with the plant extract, blasticidin S, and tetrandrine, a recognized ABC transporter inhibitor. Four ABC transporter genes were prominently activated by blasticidin S treatment, but were suppressed by combinational treatment of blasticidin S with the plant extract, or with tetrandrine that didn't show cellular toxicity by itself in this study. Mycelial death was detected via confocal microscopy at 24 h after plant extract treatment. Finally, subsequent rice field study revealed that the plant extract had high control efficacy of 63.3% and should be considered a biopesticide for rice blast disease. These results showed that extract of L. foenum graecum Herba suppresses M. oryzae ABC transporter genes inducing mycelial death and therefore may be a potent novel biopesticide.

• Journal of Forest and Environmental Science
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• 제36권3호
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• pp.207-218
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• 2020

Ashwagandha is an important ancient medicinal crops, being affected with many diseases, among which leaf blight caused by Alternaria alternata has become the constraint resulting in huge yield losses. Continuous usage of chemical methods leads to environment, soil and water pollution. Whereas biological control of diseases is long lasting, inexpensive, eco-friendly and harmless to target organisms. In this context, it is aimed to evaluate five Trichoderma strains viz. Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433 and T. harzianum IMI-392434 as bio-control efficacy against A. alternata and growth promoting effect in Ashwagandha. All the Trichoderma strains had varied antagonistic effects against the pathogen. In dual culture technique, the strain T. harzianum IMI-392433 showed maximum percentage inhibition of mycelial growth (54.89%) followed by T. harzianum IMI-392432 (53.83%), T. harzianum IMI-392434 (48.94%) and T. virens IMI-392430, (43.62%) against the pathogen, while the least inhibition percentage was observed with the T. pseudokoningii IMI-392431 (36.60%). The culture filtrate of the Trichoderma strain, T. harzianum IMI-392433 recorded highest inhibition on the mycelial growth (39.05%) and spore germination (80.77%) of pathogen and the lowest was recorded in T. pseudokoningii IMI-392431 (20.45 and 50%). Moreover, seeds treated with spore suspension of the strain T. harzianum IMI-392433 reduced the percentages of disease severity index significantly. The strain T. harzianum IMI-392433 also significantly increased seed germination %, seedling vigor and growth of Ashwagandha. The correlation matrix showed that root yield per plant of Ashwagandha had significant and positive correlation with plant height (r=0.726^⁎⁎), number of leaf (r=0.514^⁎⁎), number of primary branch (r=0.820^⁎⁎), number of secondary branch (r=0.829^⁎⁎), fresh plant weight (r=0.887^⁎⁎), plant dry weight (r=0.613^⁎⁎), root length (r=0.824^⁎⁎), root diameter (r=0.786^⁎⁎), root dry weight (r=0.739^⁎⁎) and fresh root weight (r=0.731^⁎⁎). The significant and negative correlation (r=-0.336^⁎⁎) was observed with the root yield and percentages of disease severity index. The study recognized that the T. harzianum IMI-392433 strain performed well in inhibiting the mycelial growth and reduced the percentages of disease severity index of pathogen as well as increased the plant growth in Ashwagandha.

• 미생물학회지
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• 제42권2호
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• pp.83-88
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• 2006

국내에서 식용버섯으로 이용되고 있는 8종 균주의 자실체와 균사체로부터 콜레스테롤 합성을 저해하는 lovastatin 생산과 고지혈증 억제활성을 탐색하였다. TLC 분석으로 lovastatin생산 유무를 검색한 결과 자실체와 균사체의 추출물에 대해 Rf값이 표준물질콰 같은 약 0.46에서 뚜렷한 밴드가 형성됨을 확인하였다. 자실체로부터 lovastatin 추출을 위한 용매로는 water/acetonitrile/methanol (5:2.5:2.5)을 사용하였을 매 가장 효과적인 lovastatin 생산량을 보였다. Lovastatin 생산량은 자실체 중에서는 Pleurotus ostreatus가 0.98 mg/g (dry biomass)으로 가장 높은 생산량을 나타냈고 균사체 배양액 추출물에 대해서도 P. ostreatus가 21.90 mg/L로 높은 생산량을 나타냈다. 3-Hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase 저해활성에서는 자실체에서 P ostreatus가 67.8%, 균사체에서 P. ostreatus와Laetiporus sulphureus가 각각 37.2%, 29.1%의 저해활성을 보였다. L. sulphureus는 lovastatin 생산량에 비해 높은 저해활성을 나타내서 lovastatin 이외의 다른 고지혈증 억제물질을 GC/MS로 분석한 결과 대사산물로 분비되는 식물성 sterol 물질인 campesterol과 gamma-sitosterol이 검출되었다.

• Mycobiology
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• 제39권1호
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• pp.26-32
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• 2011

Powdery mildew is one of the most devastating diseases in cucurbits. Crop yield can decline as the disease severity increases. In this study, we evaluated the effect of silver nanoparticles against powdery mildew under different cultivation conditions in vitro and in vivo. Silver nanoparticles (WA-CV-WA13B) at various concentrations were applied before and after disease outbreak in plants to determine antifungal activities. In the field tests, the application of 100 ppm silver nanoparticles showed the highest inhibition rate for both before and after the outbreak of disease on cucumbers and pumpkins. Also, the application of 100 ppm silver nanoparticles showed maximum inhibition for the growth of fungal hyphae and conidial germination in in vivo tests. Scanning electron microscope results indicated that the silver nanoparticles caused detrimental effects on both mycelial growth and conidial germination.

• 한국미생물·생명공학회지
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• 제21권6호
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• pp.594-599
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• 1993

In the course of screening for microbial metabolites employing human cancer cell line, we identified a mycelial extract of Streptomyces sp. 1365, which are effective on growth inhibition and morphological change of MCF-7, human breasr cancer cell line. By repeased column chromatography and recrystallization process, yellow needle crystals were obtained as an active compound and identified as resistomycin by spectral analysis.

• 한국균학회지
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• 제27권1호통권88호
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• pp.32-38
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• 1999

양식 가물치로부터 Saprolegnia sp.를 분리하고 그들의 일부 생리학적 특성과 제어를 위한 식물 추출물(精油)을 탐색하였다. 분리된 Saprolegnia sp. 영양체 생장 최적 온도는 $25^{\circ}C$이었고, 최적 pH는 6.0이었으며, 최적 NaCl 농도는 0%이었다. 또한 phosphate 10 mM 농도와 casamino acid 10mg/L농도에서 균사의 생장은 잘되었다. Saprolegnia sp.의 제어 정도를 조사하기 위해 쑥, 편백, 측백나무로부터 정유를 분리하여 10, 100, 500, 1,000, 1,500, 2,000ppm에서 처리한 결과 쑥 정유는 처리농도 10 ppm 이상 농도에서부터 억제 양상이 나타나다가 농도가 높아질수록 더 많은 억제양상을 나타냈다. 측백과 편백나무 정유를 처리한 것에서는 10ppm이상 처리 농도에서부터 억제되기 시작하여 그 이상의 처리 농도에서는 상당한 균사 생장 제어 효과를 나타내다가 500 ppm 이상 처리 농도에서는 완전한 제어 효과를 나타냈다. 또한 Saprolegnia sp.에 감염된 가물치의 조직 병리학적인 조사를 실시한 결과 균사가 감염된 근육조직 부분에는 깊은 곳까지 균사가 침투하였고, 아가미의 세포는 곤봉형태를 나타냈으며, 간조직 세포에서는 일부가 괴사되었고 부분적으로 ceroid 물질이 침착되어 있었다. 또한 비장조직 세포에서는 일부 괴사된 세포를 관찰하였고, ceroid 물질의 침착을 볼 수 있었다. 신장조직은 세뇨관의 상피세포에서 일부 괴사를 관찰하였고, 조혈 조직에는 ceroid 물질의 침착상태가 나타났다.

• 생약학회지
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• 제15권2호
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• pp.61-73
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• 1984

To investigate antitumor component of Lyophyllum decastes, the aqueous extract of its shake-cultured mycelia was subjected to antitumor test against sarcoma 180 cells implanted in ICR mice. The extract showed an inhibition ratio of 65.4% and was found to consist of a polysaccharide moiety and a protein moiety. After purification with DEAE-Sephadex A-50 ion exchange chromatography, Fraction D showed the highest inhibition ratio of 75.7%. The antitumor constituent was examined for immunoaccelerating activity and was found to increase macrophage accumulation in the peritoneal cavity and plaque forming cells of the spleen cells. It was named lyophyllan after the genus name.

• Journal of Applied Biological Chemistry
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• 제49권4호
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• pp.131-134
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• 2006

The in vitro anti-fungal activity of hydroxylated fatty acids obtained from microbial conversion by Psuedomonas aeruginosa PR3 using ricinoleic acid(RA), eicosadienoic acid(EDA) and conjugated linoleic acid(CLA) as substrates, was investigated. Bioconverted hydroxylated fatty acids showed different anti-fungal activities potentials against the range of phytopathogenic fungi such as Botrytis cinerea, Rhizoctonia solani, Fusarium oxysporum, Sclerotonia sclerotiorum, Colletotricum capsici, Fusarium solani and Phytophthora capsici. RA and EDA showed up to 50% fungal mycelial inhibition at the concentration of $5{\mu}l\;ml^{-1}$. RA, EDA and CLA also exhibited anti-fungal activities with minimum inhibitory concentration(MIC), ranging from 500 to $1000{\mu}g\;ml^{-1}$. Screening was also carried out using varied concentrations of bioconverted RA and EDA for determining the anti-fungal effect on the spore germination of different fungi. Bioconverted RA and EDA showed a considerable degree of spore germination inhibition.