• 농약과학회지
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• 제6권1호
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• pp.42-44
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• 2002

1999년 대관령 고랭지에서 재배되는 백합에 막대한 피해를 주는 병이 발생하여, 이 병의 원인 병원균의 동정과 화학적 방제 방법을 찾기 위한 시험을 수행하였다. 백합에서 분리된 12 균주 모두는 P. cactorum으로 동정되었다. 백합 역병균에 대한 metalaxyl의 약제 반응을 조사한 결과 분리된 균주 모두는 $10{\mu}g/mL$에서 전혀 균사가 생장하지 못하므로 감수성 균인 것으로 나타났다. 백합 역병균(P. cactorum PC-1) 방제 약제를 선발하기 위하여 11약제를 선택하여 스크리닝을 수행한 결과, dimethomorph, ethaboxam, metalaxyl, oxadixyl은 $10{\mu}g/mL$에서 병원균의 생장을 완전히 억제하여 우수한 약효를 나타냈다. 따라서 metalaxyl과 같은 phenylamide계 살균제 및 다른 역병 방제용 살균제의 살포는 백합 역병의 방제에 효과적일 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제23권11호
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• pp.1493-1499
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• 2013

A novel radiation-resistant Filobasidium sp. yeast strain was isolated from seawater. Along with this strain, a total of 656 yeast isolates were purified from seawater samples collected from three locations in the West Sea of Korea and assessed for their radiation tolerance. Among these isolates, five were found to survive a 5 kGy radiation dose. The most radiation-resistant strain was classified as Filobasidium sp. based on 18S rDNA sequence analysis and hence was named Filobasidium RRY1 (Radiation-Resistant Yeast 1). RRY1 differed from F. elegans, which is closely related to RRY1, in terms of the optimal growth temperature and radiation resistance, and was resistant to high doses of ${\gamma}$-ionizing radiation ($D_{10}$: 6-7 kGy). When exposed to a high dose of 3 kGy irradiation, the RRY1 cells remained intact and undistorted, with negligible cell death. When these irradiated cells were allowed to recover, the cells fully repaired their genomic DNA within 3 h of growth recovery. This is the first report in which a radiation-resistant response has been investigated at the physiological, morphological, and molecular levels in a strain of Filobasidium sp.

• 한국균학회지
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• 제25권4호통권83호
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• pp.320-329
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• 1997

병든 오이, 토마토, 딸기로부터 분리한 Botrytis cinerea을 Paul(1928)의 형태형(morphological phenotypes) 분류 기준에 따라 포자형, 균핵형, 균사형으로 나눌 때 대부분의 균주는 균핵형으로 나타났다. Benzimidazole 및 dicarboximide계 살균제에 대한 감수성 및 저항성 반응 차이는 형태형과는 무관하였다. 포자의 표면 구조를 주사형 전자현미경으로 관찰한 결과 모두 봉상으로 형태형 간에 차이가 없었다. 형태형 간 병원성을 비교할 때, 균사형의 균주가 가장 병원성이 높았으며, 포자형은 병원성이 다른 형보다 낮게 나타났다. 병원성과 곰팡이의 phenol oxidase, pectin methyl esterases (PME), amylases, cellulases, ureases, glucosidases 및 proteinases 활성과의 관계를 조사하기 위하여 형태형이 다른 선발된 균주들의 효소 활성을 조사한 결과, Phenol oxidase, ${\beta}-glucosidase$는 각 형태형 간에 차이가 없었으나, PME, amylase, cellulase, urease, proteinase의 활성은 각 형태형간에 차이를 나타내어 병원성과 이들 효소 활성의 관련성이 있었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2011년도 임시총회 및 추계학술발표회
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• pp.14-14
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• 2011

Polyamines (putrescine, spermidine and spermine) play pivotal roles in plant defense to different abiotic and biotic stresses. In order to understand the function of ginseng spermidine synthase gene, a key gene involved in biosynthesis of polyamines, transgenic plant was generated in Arabidopsis. The transgenic plants exhibited high levels of polyamines compared to the untransformed control plants. We investigated the tolerance capacity of transgenic plants to abiotic stresses such as salinity and copper stress. In addition, transgenic plants also showed increased resistance against one of the important fungal pathogens of ginseng, the wilt causing Fusarium oxysporum and one of important bacteria, bacterial blight causing Pseudomonas syringae. However, an activity of the polyamine catabolic enzyme, diamine oxidase (DAO) was increased significantly in F. oxysporum and P. syringae infected transgenic plant. Polyamine catabolic enzymes which may trigger the hypersensitive response (HR) by producing hydrogen peroxide ($H_2O_2$) seem act as an inducer of PR proteins, peroxidase and phenyl ammonium lyase activity. The transgenic plants also contained higher antioxidant enzyme activities, less MDA and $H_2O_2$ under salt and copper stress than the wild type, implying it suffered from less injury. These results strongly suggest an important role of spermidine as a signaling regulator in stress signaling pathways, leading to build-up of stress tolerance mechanisms.

• 식물병연구
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• 제21권3호
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• pp.161-179
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• 2015

식물은 다양한 병원성 미생물에 대하여 효과적인 방어 기제를 발전시켜 왔다. 최근 유전체와 다중 오믹스 기술의 발전은 우리에게 미생물 인자에 의한 식물 면역을 폭넓게 이해할 수 있는 단초를 제공해 주었다. 하지만 아직까지는 이러한 기술을 병 방제 전략에 이용한 적은 많지 않다. 그래서 본 리뷰에서 식물 면역의 기본 개념을 소개하고 최근 얻어진 결과들을 소개하였다. 덧붙여 이미 논문에서 발표된 진균, 세균, 바이러스 유래 결정인자에 의한 생물적 방제 가능한 방법에 대해 기술하였다. 특히 미생물 결정인자인 chitin, glucan, LPS/EPS, 미생물분자패턴, 항생제, 식물유사호르몬, AHLs, harpin, 비타민, 휘발성물질에 대한 결과를 자세하게 기술하였다. 이 리뷰를 통하여 많은 과학자들과 농민들이 미생물 결정인자 기반의 생물적 방제에 대한 지식이 폭넓어지고, 다양한 미생물 결정 인자가 앞으로 농업현장의 종합적인 병방제 전략의 하나로 자리매김하기를 바란다.

• Mycobiology
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• 제34권4호
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• pp.219-229
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• 2006

Seventeen microbial species including 10 fungal taxa, two yeasts and five bacteria, were isolated from freshly prepared orange, guava and banana juices kept in open bottles at room temperature for 7 days. Eight different essential oils, from local herbs, were tested for their antimicrobial activity against these test organisms. The essential oils of Cymbopogon citratus, Ocimum basilicum and Origanum majorana were found to be highly effective against these microorganisms. Aspergillus niger, A. flavus and Saccharomyces cerevisiae, the most prevalent microorganisms in juice, showed the highest resistance against these essential oils. GC-MS analysis showed that while e-citral, a'-myrcene, and z-citral represent the major components (75.1 %) of the essential oil of Cymbopogon citratus; bezynen,l-methyl-4-(2-propenyl), 1,8-cineole and trans-a'-bisabolene were the main components (90.6%) of Ocimum basilicum; whereas 3-cyclohexen-l-0l,4-methyl-l(l-methylethyl)-(CAS), c-terpinene and trans-caryophyllene represent the major components (65.1%) of Origanum majorana. These three essential oils were introduced into juices by two techniques namely, fumigation and direct contact. The former technique showed more fungicidal effect than the latter one against A. flavus, A. niger, and S. cerevisiae. The essential oil of Cymbopogon citratus by comparison to other test oils showed the strongest effect against these fungi with a minimum inhibitory concentration of $1.5\;{\mu}l/ml$ medium and a sublethal concentration of $1.0\;{\mu}l/ml$. The antimicrobial activity of this oil is thermostable at $121^{\circ}C$ for 30 min.

• 식물분류학회지
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• 제35권4호
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• pp.313-335
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• 2005

식물규소체는 토양과 물에 용해된 규소가 이산화규소($SiO_2$)의 형태로 식물체내의 여러 기관 또는 표피세포에 축적되면서 형성되어 식물의 성장과 발달에 중요한 영향을 미치는 것으로 밝혀지고 있어, 식물의 규소체에 관한 연구가 시행되고 있다. 따라서 본 연구에서는 한국산 사초과 (Cyperaceae) 식물 13속 228종 중, 12속 136종의 잎의 표피형에서 밝힌 규소체의 형태를 검토하여 정리하였다. 그 결과 한국산 사초과 식물은 규소체의 모양에 따라 2 그룹으로 구분되었다. 제 1 그룹은 원추형(conical body)의 규소체를 나타내고, 골풀아재비속(Rhynchospora), 검정방동산이속(Fuirena), 너도고랭이속(Scleria), 사초속(Carex)과 황새풀속(Eriophorum)이 이에 속한다. 제 2 그룹은 규소체의 모양이 원추형을 중심으로 많은 위성형을 보이며, 방동산이속(Cyperus), 올챙이골속(Scirpus), 바늘골속(Eleocharis), 하늘지기속(Fimbristylis), 파대가리속(Kyllinga), 모기골속(Bulbostylis)과 세대가리속(Lipocarpha.)이 속한다.

• KSBB Journal
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• 제13권2호
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• pp.214-219
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• 1998

Polymerase chain reaction(PCR) was conducted to obtain the gene encoding glucose oxidase(GOD) from Aspergillus niger(ATCC 2110) and the DNA sequence determined was coincided with published GOD sequence from A. niger. Recombinant transforming vector containing GOD and hygromycin B(hyg.B) resistant gene(hph) was constructed and used for further transformation of A. niger ATCC 2110. Selectivity of hyg.B against A. niger differed depending on which media were used i.e., nutrient-rich media such as potato dextrose agar(PDA) and complete medium(CM) showed only 50% growth inhibition at 400 $\mu$m ml$^-1$ of hyg.B while the minimal media inhibited mycelial growth completely at 200 $\mu$m ml$^-1$ of hyg.B. Twenty to sixty putative transformants were isolated from the hyg.B-containing minimal top agar, transferred successively onto alternating selective and nonselective media for a mitotic stability of hyg.B resistance and, then, single-spored. Among the stable transformants, the transformant(GOD1-6) grown by flask culture showed the considerable increase of extracellular GOD activity, which was estimated to the degree of 50% - 100% comparing to that of wild type. Transformation of tGOD1-6 was resulted from integration of the vectors into heterologous as well as homologous regions of the A. niger genome. Southern blot analysis revealed that there were two independent integrations of vector into fungal genome and one into the GOD gene due to homologous recombination. In addition, GOD activity and sodium gluconate production when tGOD1-6 was fed-batch fermented were enhanced 11 fold and 2.25 fold, respectively, compared to that of the wild type.

• 약학회지
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• 제59권6호
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• pp.259-265
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• 2015

In recent, there are increasing reports about pharmacological activities of Crataegi Fructus which has been used for many centuries as medicinal and food sources in East Asia. However, its antifungal efficacy needs to be investigated. Thus, in the current study, we determined synergistic antifungal activity of the Crataegi Fructus extract (CFE) when combined with fluconazole (FLC) against disseminated candidiasis due to Candida albicans. This fungus is one of the most problematic fungal pathogens. Data resulting from a microdilution susceptibility test showed that CFE had a dose-dependent antifungal activity. When the extract was combined with FLC, the activity was synergistic. For example, the antifungal activity by the combination of CFE at $20{\mu}g/ml$ plus FLC at $0.1{\mu}g/ml$ was 4 times more effective than antifungal activity by FLC alone at the same concentration (P<0.05). In the murine model of disseminated candidiasis, the combination therapy potentiated resistance of mice, resulting in 80% of C. albicans-infected animals surviving the entire period of 40 days observation, whereas mice given CFE alone or FLC alone all died with 17 and 23 days, respectively, although they survived longer than the untreated control animals (P<0.05). The CFE's antifungal activity seemed to be related to the blockage of hyphal production of C. albicans yeast cells. In summary, CFE has a synergistic antifungal activity, which can be produced by combining CFE with FLC. Thus, our data strongly indicate that CFE may be a potential candidate as an antifungal agent for combination therapy.

• Journal of Forest and Environmental Science
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• 제33권4호
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• pp.322-329
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• 2017

As a result of contemporary environmental concerns, a number of studies from plants' tissues as one of the alternatives to conventional chemicals are increasingly investigated. In tandem with these trends, Lagenaria breviflora (LB) fruit, reputed as antiviral and depilatory agents in the Yoruba folkloric medicine was examined on Vitex doniana wood to ascertain its antifungal activity. Fungicides of 25%, 50%, 75%, and 100% LB fruits formulations (concentrations) were developed through simple one-step mechanical-forming process, including control. In this study, the yield, the chemical compositions, the absorption capacity of the fungicides and wood weight losses (WWL) analysis were evaluated to investigate the antifungal activity of LB fruit on wood. The fruit extract yielded 35.4% of fresh juice weight. LB fruits contained total: alkaloids ($8.78{\pm}0.21mg/mL$), flavonoids ($2.01{\pm}0.02mg/mL$), phenol ($7.42{\pm}0.09mg/mL$), saponins ($11.00{\pm}0.10mg/mL$) and tannins ($5.47{\pm}0.05mg/mL$) contents. All the formulations provided effective protection against the tested wood fungi compared to control. Interestingly, the antifungal activity of 50% and 25% formulations of 6.8% WWL and 9.9% WWL satisfied the excellent fungal resistance class description against white rot fungus (Ganoderma lucidum) and brown rot fungus (Fibroporia vaillantii), respectively according to ASTM D 2017. These results thus, support LB fruit as a strong potential source of natural antifungals for industrial wood production.