• 한국토양비료학회지
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• 제33권4호
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• pp.302-309
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• 2000

미생물제의 퇴비부숙효과를 검토하기 위하여 국내에 유통되고있는 Lacto외 4종 미생물제에 대한 퇴비부숙 촉진 효과를 보면 볏짚에서는 락토 및 천보, 생력등 일부 미생물(微生物)제의 처리에 의하여 초기에 부숙촉진경향이 관찰되었으나 초기에 부숙이 촉진되었던 처리는 후기에 부숙속도가 늦어지고 초기에 부숙속도가 늦었던 처리는 후기에 부숙속도가 빨라짐으로서 결국 미생물제처리 40일경에는 미생물제 사이에 뚜렷한 차이가 인정되지 않았다. 또한 미생물제를 시용하면 볏짚부숙중에 사상균수의 증가가 현저하였으며 볏짚의 부숙과 사상균수의 변동과 일치하는 경향을 보였으나, 계분톱밥부숙에 미치는 미생물제의 영향을 보면 퇴적초기에는 세균, 방선균, 사상균 모두 균수가 극히 적었으며 세균수만이 시간이 경과함에 따라 균수의 증가가 현저한 점으로 미루어 볼 때 세균이 계분톱밥퇴비의 부숙에 밀접한 관련이 있는 것으로 판단되었다.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.832-838
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• 1999

Two different types of lipases (lipase I and lipase II) secreted into culture medium by Rhizopus sp. L-I were purified using a hydrophobic chromatography and were partially characterized. Both enzymes were monomeric as revealed by SDS-PAGE and gel filtration. The molecular masses of the enzymes were identified as 45 kDa (lipase I) and 69 kDa (lipase II). The isoelectric points were estimated to be 3.6 and 5.2 for lipase I and lipase II, respectively. pH and temperature activity optima for lipase I were as 7.5 and $50^{\circ}C$, respectively, whereas the corresponding parameters for lipase II were 6.0 and $45^{\circ}C$. The amino terminal sequences of lipase I and lipase II, determined by Edman degradation, were found to be Leu-Val-Met-Ile-Gln-Arg and Leu-Val-Met-Lys-Gln-Arg, respectively. By western blotting analysis, the two lipases were found to have a common antigenic determinant. Immuno-electron cytochemistry conducted with polyclonal anti-lipase I antibody indicated the enzyme located in both the periplasm and the adjacent vesicles of fungal hyphae. Fortunately, the sites on the cell envelope where lipase was exported into the culture medium was also identified.

• The Plant Pathology Journal
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• 제29권1호
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• pp.52-58
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• 2013

Fusarium head blight (FHB) caused by the filamentous fungus Fusarium graminearum is one of the most severe diseases threatening the production of small grains. Infected grains are often contaminated with mycotoxins such as zearalenone and trichothecences. During survey of contamination by FHB in rice grains, we found a bacterial isolate, designated as BN1, antagonistic to F. graminearum. The strain BN1 had branching vegetative hyphae and spores, and its aerial hyphae often had long, straight filaments bearing spores. The 16S rRNA gene of BN1 had 100% sequence identity with those found in several Streptomyces species. Phylogenetic analysis of ITS regions showed that BN1 grouped with S. sampsonii with 77% bootstrap value, suggesting that BN1 was not a known Streptomyces species. In addition, the efficacy of the BN1 strain against F. graminearum strains was tested both in vitro and in vivo. Wheat seedling length was significantly decreased by F. graminearum infection. However, this effect was mitigated when wheat seeds were treated with BN1 spore suspension prior to F. graminearum infection. BN1 also significantly decreased FHB severity when it was sprayed onto wheat heads, whereas BN1 was not effective when wheat heads were point inoculated. These results suggest that spraying of BN1 spores onto wheat heads during the wheat flowering season can be efficient for plant protection. Mechanistic studies on the antagonistic effect of BN1 against F. graminearum remain to be analyzed.

• 혜화의학회지
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• 제10권2호
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• pp.91-96
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• 2002

We arrived at the following conclusions after we have studied esophagitis through the literatures of oriental and western medicine. 1. The western medical causes of acute esophagitis are corrosiveness chemical material, esophageal or gastric disease, trauma, blister stomatitis, filamentous fungus infection and uremia of chronic patient etc, and the oriental medical causes are qi and blood stagnation, blood stasis and stagnation, stagnant phlegm by coldness, heating, dyspepsia and food poisoning etc. 2. The western medical causes of chronic esophagitis are malfunction of lower esophageal sphincter, esophageal tom chink and hernia, increase of gastric pressure by overeating, fatness, pregnancy and ascites etc, and the oriental medical causes are asthenic cardiac qi, hepatic qi attacking stomach by seven kinds of depression, cold-damp stagnation and insufficiency of gastric qi by overeating, excessive drinking and sexual indulgence etc. 3. The main symptoms of acute esophagitis are severe chest pain, instantly vomiting, swallowing pain etc, and chronic esophagitis are occasionally light chest pain, heart bum, anorexia, dysphagia, dizziness, general body weakness etc. These symptoms are come under thoracic obstruction, acid regurgitation, vomiting and chest pain of oriental medicine. 4. The western medical diagnoses of acute and chronic esophagitis have used radiation test, esophageal endoscopy, esophageal pressure test and biopsy etc, and the oriental medical diagnoses have used syndrome differentiation by four examination of inspection, listening and smelling examination, inquiring, pulse-taking and palpitation. 5. The western medical treatments of acute esophagitis have regarded preservation stability of esophagus as a principle, and the oriental medical treatments mainly have used expelling pathogen of expelling cold and regulating qi, cooling and removing stasis, promoting blood circulation to remove blood stasis, eliminating phlegm and regulating qi. 6. The western medical treatments of chronic esophagitis have regarded decrease flowing backward of gastric juice as a purpose, and the oriental medical treatments mainly have used strengthening body resistance of replenishing and strengthening cardioqi, dispersing stagnated hepatoqi, expelling cold and dehygrosis, invigorating stomach and nourishing qi.

• Mycobiology
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• 제43권4호
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• pp.458-466
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• 2015

Oak tree death caused by symbiosis of an ambrosia beetle, Platypus koryoensis, and an ophiostomatoid filamentous fungus, Raffaelea quercus-mongolicae, has been a nationwide problem in Korea since 2004. In this study, we surveyed the yeast species associated with P. koryoensis to better understand the diversity of fungal associates of the beetle pest. In 2009, a total of 195 yeast isolates were sampled from larvae and adult beetles (female and male) of P. koryoensis in Cheonan, Goyang, and Paju; 8 species were identified by based on their morphological, biochemical and molecular analyses. Meyerozyma guilliermondii and Candida kashinagacola were found to be the two dominant species. Among the 8 species, Candida homilentoma was a newly recorded yeast species in Korea, and thus, its mycological characteristics were described. The P. koryoensis symbiont R. quercusmongolicae did not show extracelluar CM-cellulase, xylanase and avicelase activity that are responsible for degradation of wood structure; however, C. kashinagacola and M. guilliermondii did show the three extracellular enzymatic activities. Extracelluar CM-cellulase activity was also found in Ambrosiozyma sp., C. homilentoma, C. kashinagacola, and Candida sp. Extracelluar pectinase activity was detected in Ambrosiozyma sp., C. homilentoma, Candida sp., and M. guilliermondii. All the 8 yeast species displayed compatible relationships with R. quercus-mongolicae when they were co-cultivated on yeast extract-malt extract plates. Overall, our results demonstrated that P. koryoensis carries the yeast species as a symbiotic fungal associate. This is first report of yeast diversity associated with P. koryoensis.

• KSBB Journal
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• 제15권5호
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• pp.507-513
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• 2000

고지혈증 치료제인 lovastatin을 Aspergillus terreus로부터 생산하기 위해 발효조 배양설험에서 교반속도와 pH에 대한 영향올 조사하였다. 최적 교반속도는 400 rpm이었고 pH는 5.8로 유지하였을 때 lovastatin 생산이 최대였으며, 교반속도 보다 pH가 lovastatin 생산에 더 많은 영향을 미치는 것으로 나타났다 L-tryptop뼈n과 L-histi빼le의 첨가시기에 따른 lovastatin 생산량을 실험한 결과, 둘다 발효초기부터 첨가하여 배양하 는 것이 효과적이었다 L-tryptophan을 발효초기에 첨가한 최 적배지와 최적 환경조건인 교반속도 400 rpm, pH 5.8에서 회 분식 배양을 수행한 결과 기본배지를 이용하여 실험한 배양 결과보다 약 10배 정도 많은 836 mg/L이었고, 생산성은 3.5 mg/L.hr였다

• The Plant Pathology Journal
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• 제37권2호
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• pp.200-203
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• 2021

Rice blast caused by the filamentous fungus Magnaporthe oryzae, is arguably the most devastating rice disease worldwide. Development of a high-throughput and reliable field blast resistance evaluation system is essential for resistant germplasm screening, resistance genes identification and resistant varieties breeding. However, the occurrence of rice blast in paddy field is easily affected by various factors, particularly lack of sufficient inoculum, which always leads to the non-uniform occurrence and reduced disease severity. Here, we described a procedure for adequately inducing the occurrence of rice seedling blast in paddy field, which involves pretreatment of diseased straw, initiation of seedling blast for the first batch of spreader population, inducing the occurrence of the second batch of spreader population and test materials. This procedure enables uniform and consistent infection, which facilitates efficient and accurate assessment of seedling blast resistance for diverse rice materials.

• KSBB Journal
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• 제16권1호
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• pp.87-94
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• 2001

곰팡이 균인 Aspergillus terreus로서 고지혈증인 치료제인 lovastatin을 생산하기 위해 탄소원 조절에 의한 유가식 배양을 통해 lovastatin 생산 발효 조건을 확립하고자 하였다. 또한 발효시 곰팡이의 형태구조가 이차대사산물 생산에 중요함으로 유가식 배양에서의 공급배지농도와 공급속도에 따른 형태 구조의 변화가 생산성과 관련이 있는지를 구명하였다. Glucose 용액을 일정하게 또는 증가시켜 공급하는 방법을 실험하였으며 이 때 펠 의 분포를 비교하였다. Glucose 용액을 일정하게 공급한 경우가 1 mm 이하의 펠 이 더 많이 분포하였으며, lovastatin 생산량도 높았다. Lovastatin 생산에 적절한 펠 의 크기가 1 mm이었다는 연구 결과와 일치하였다. 또한 배양 방법 중 3일간 회분 배양 후 4일째부터 glucose를 일정하게 공급한 경우에서 높은 lovastatin 생산량을 나타내었다. 회분식 발효에서 lovastatin 생산을 위한 물리적 조건 중 교반 속도는 400 rpm으로 조절하였고 pH에 대한 영향을 조사하였다. 그 결과 pH 5.8로 유지하였을 때 lovastatin 생산량은 pH 7.4의 7배 이상인 384 mg/L로서 발효 기간 중 pH 조절이 중요하다는 것을 알 수 있었다. 플라스크에서의 유가식 배양과 회분식 배양결과를 토대로 하여 발효조에서 유가식 배양시 pH 5.8, 400 rpm, 초기 glucose 농도를 30 g/L 로 하여 3일간 회분 배양 후 4일째부터 180 g/L의 glucose 용액을 공급한 결과, 회분식 배양의 lovastatin 생산량보다 1.5배 많은 547 mg/L를 얻었으며, 생산성은 3.25 mg/L $\cdot$ hr였다.

• KSBB Journal
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• 제14권1호
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• pp.36-44
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• 1999

고지혈증 치료제인 Lovastatin을 Aspergillus terreus로부터 생산하기 위해 최적의 탄소원, 질소원, 인산염 및 아미노산을 선정하였다. 단일 탄소원에서는 글리세롤 45mL/L가 Lovastatin 256mg/L로 포도당 45g/L의 기본배지보다 약 3.5배 이상의 높은 Lovastatin 생산량을 나타내었다. 탄소원이 지방산 합성에 이용되는 것을 차단하고 Lovastatin으로의 합성을 촉진하기 위해 기름 증류를 탄소원으로 이용한 결과, 높은 Lovastatin 생산량과 균재량을 나타내었으나, 글리세롤 45mL/L가 Lovastatin 생산량이 낮았다 포도당 50g/L와 글리세롤 50mL/L를 혼합한 복합 탄소원이 Lovastatin 298mg/L로 기본배지에 비해 약 4배 이상의 가장 높은 Lovastatin 생산량을 나타냈었다. 질소원의 영향은 뚜렷하여 질소원에 따라 Lovastatin 생산량이 큰 차이를 나타내었으며, 그 중에서 peptonized milk가 가장 Lovastatin 생산량이 높았다. 인산염 중에서는 $K_2HPO_4$가 가장 높은 Lovastatin 생산량을 나타내었다. 이상에서 얻어진 최적 배지에 각종 아미노산을 첨가한 결과 L-hisbhine과 L-tryptophan이 가장 효과적이었으며, 최적 농도는 둘다 6g/L였다.

• Journal of Microbiology and Biotechnology
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• 제30권2호
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• pp.206-215
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• 2020

Trichoderma reesei is the major filamentous fungus used to produce cellulase and there is huge interest in promoting its ability to produce higher titers of cellulase. Among the many factors affecting cellulase production in T. reesei, the mycelial phenotype is important but seldom studied. Herein, a close homolog of the Neurospora crassa COT1 kinase was discovered in T. reesei and designated TrCOT1, which is of 83.3% amino acid sequence identity. Functional disruption of Trcot1 in T. reesei by RNAi-mediated gene silencing resulted in retarded sporulation on potato dextrose agar and dwarfed colonies on minimal medium agar plates containing glucose, xylan, lactose, xylose, or glycerol as the sole carbon source. The representative mutant strain, SUS2/Trcot1i, also displayed reduced mycelia accumulation but hyperbranching in the MM glucose liquid medium, with hyphal growth unit length values decreased to 73.0 ㎛/tip compared to 239.8 ㎛/tip for the parent strain SUS2. The hyperbranching phenotype led to slightly but significantly increased cellulase secretion from 24 to 72 h in a batch culture. However, the cellulase production per unit of mycelial biomass was much more profoundly improved from 24 to 96 h.