• 한국미생물·생명공학회지
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• 제24권2호
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• pp.185-190
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• 1996

Some microorganisms including yeasts produce surface tension-decreasing biosurfactants. The strain G-1, the best producer of biosurfatants was isolated from the soil and identified as Rhodotorula sp., which was not discribed any report. The Rhodotorula sp. G-1 produced biosurfactant from vegetable oils, but failed to produce it from n-alkane or carbohydrate. Yeast extract was found to be more effective for the biosurfactant production as nitrogen source than any other inorganic nitrogen source. The composion of the optimal medium contained the following conponents: soybean oil 4%, glucose 2%, yeast extract 0.5%, KH$^{2}$PO$^{4}$ 0.1%, K$^{2}$HP0$^{4}$ 0.l%, MgSO$^{4}$ 5%, CaCl$^{2}$ 0.01%, NaCl 0.01%, pH 6.0. The surface tension activity was increased to 14% when, at first, the culture broth was fermented with only soybean oil as carbon sourse, and after 90 hours, feeded glucose, than that Of glucose and soybean oil added to it simultaneously. The maxium yield of the biosurfactant was about 15 g/l by after 90 hours, the feeding method of glucose.

• Applied Biological Chemistry
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• 제42권2호
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• pp.99-104
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• 1999

제주도내 25개 지점의 토양시료로부터 총 703 주의 방선균을 분리하였다. 네 종류의 배지 중 soil extract를 함유한 arginine glycerol salts agar가 다양한 방선균을 분리하는데 가장 적합하였으며, 목장초지 토양이 다른 지역의 토양에 비해서 방선균의 다양성과 밀도면에서 가장 좋은 분리원이었다 순수분리된 526개의 균주를 대상으로 Escherichia coli, Staphylococcus aureus 및 Pseudomonas solanacearum을 검정균으로 하여, 항균성 물질 생산여부를 검정한 결과, 생산균주의 발생빈도는 분리 및 배양에 사용한 배지의 종류에 따라서 $0{\sim}32.8%$로 많은 차이를 보였다. 세 종류의 검정균에 대하여 동시에 항균활성을 나타내는 10개 균주 중에서 pH 안정성과 열 안정성이 비교적 높은 물질을 생산하는 BL106Ba균주를 선택하여 등정한 결과, Streptomyces속에 속하며 S. albosporeus와 가장 유사한 것으로 추정되었다. B1106Ba의 배양액을 양이온 교환수지(AG MP-50)통과와 3차의 분자량 분획(Sephadex G-10)으로 정제하여 얻은 백색의 결정은 그람 음성균 및 양성균에 대해서는 강한 항균활성을 나타내었으나, 효모에 대해서는 약한 활성을 나타내었다. 이 결정 물질을 TLC와 HPLC로 분석한 결과 네 종류의 서로 다른 항균성 화합물이 혼합되어 있는 것으로 나타났다.

• Journal of Chest Surgery
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• 제37권3호
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• pp.292-296
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• 2004

효모균은 전 세계적으로 도처에 분포하고 있는 곰팡이로서, 특히 비둘기 배설물에 의해 오염된 토양에 존재한다. 폐의 효모균증은 건강한 사람에게는 잘 발생하지 않으며 면역이 저하된 환자 특히 후천성 면역결핍증 환자에게서 호발한다. 일반적으로 증상이 없이 흉부엑스선상 고립성 또는 다발성 폐결절이 관찰되며, 절제된 조직에서의 병리학적 소견으로 진단된다. 기침이나 객담, 발열 및 무력감 등의 급성폐렴의 증상을 보일 수 있으나 질병특유의 증상은 아니다. 효모균증은 대부분의 곰팡이 염색에 의해 진단되며, 증상이 없는 고립성 폐결절을 포함하여 진단된 모든 효모균증에 있어서 약물치료를 시행한다.

• 미생물학회지
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• 제28권4호
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• pp.345-350
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• 1990

D-xylose로부터 직접 ethanol을 생산할 목적으로 D-xylose를 유일한 탄소원과 에너지원으로 이용하는 효모들을 토양, 톱밥, 썩은 나무들로부터 분리하였다. 이 균주들 가운데서 ethanol 생산력이 가장 우수한 균주는 썩은 나무로부터 분리한 Candida sp. L-16으로 동정되었다. 이균주를 이용한 ethanol 발효의 최적 조건은 진탕속도 60rpm, 배양온도 28C, 초기 pH 4.5 및 D-xylose 농도 5%이었다. 알코올 생산은 배양 4일째에 최대치에 도달했고 이때의 ethanol 농도는 2.4%(v/v)로서 이론적인 ethanol 수율은 총당에 대해 74.4%이었다.

• Journal of Microbiology and Biotechnology
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• 제16권10호
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• pp.1597-1604
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• 2006

To screen for an anti-yeast substance (AYS), many bacteria were isolated from soil and a strain AY2000 was selected. The strain AY2000 was identified as Rahnella aquatilis by morphology, biochemical properties, and 16S r-RNA nucleotide sequence analyses. The strain AY2000 showed anti-yeast activity against Candida albicans and Saccharomyces cerevisiae, whereas R. aquatilis ATCC33071 as a type strain did not show the activity against the yeasts under the same condition. The growth of yeast cell was significantly inhibited by AYS produced by the strain AY2000, as shown by optical density and MTT assay. The minimum inhibitory concentration (MIC) of the AYS against S. cerevisiae and C. albicans at $28^{\circ}C\;was\;20{\mu}g/ml\;and\;60{\mu}g/ml$, respectively. The MIC of AYS against hyphae of C. albicans at $37^{\circ}C\;was\;600{\mu}g/ml$. Scanning electron microscopic analysis revealed that yeast cells treated with AYS had an irregular form with a wrinkled and rough surface.

• 미생물학회지
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• 제22권4호
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• pp.215-222
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• 1984

Rhodotorula gl$\varkappa$tinis 세포벽에 작용하는 용해 효소 생산곰팡이를 토양으로부터 분리하였고, Aspergillus f'||'&'||'micro;mig$\alpha$tus에 속하는 species로 동정되었다. 이 세포벽 용해효소는 세표외 유도효소였으며 lytic polysaccharidase 와 protease로 구성되어 생세포 용해에 공동으로 착용하였다. 이 lytic polysaccharidase는 Ascomycetous 효모에서의 주 구성 결합인 ${\beta}-1,3-$와 ${\beta}-1$, 6-glucan에는 작용치 않았다. 이 효소는 생세포에는 역가가 낮았지만 R. glutinis의 분획된 세포액에는 protease의 도움없이 작용할 수 있었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.180-184
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• 2003

선별된 7종의 균주는 넓은 범위의 산과 담즙산에 대해 기존에 보고된 결과에 비하여 높은 내성을 나타냈고, 장내세균인 E. coli에 대해서도 우수한 항균력을 나타냈고, 항생제 tetracycline, nisin, kanamycin, ampicillin. streptomycin에 대해서도 높은 내성을 보였다. 또한 7종의 균주는 어느 정도의 산을 생성하고 있었고, 네 가지 효소 amylase, protease, lipase, cellulase에 대해서도 높은 활성을 나타냈다. 균주 특성실험 결과, 7종의 균주는 그람음성균으로 모두 구형, 비운동성이고 균체의 색은 노란색이거나 흰색을 띠고 있고, 다양한 유기물에 대하여 분해력을 지니고 있었다.

• Journal of Microbiology and Biotechnology
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• 제21권1호
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• pp.55-61
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• 2011

Forty yeast strains isolated from soils taken from different locations in Egypt were tested for their P-solubilizing activities on the basis of analyzing the clear zone around colonies growing on a tricalcium phosphate medium after incubation for 5 days at $25^{\circ}C$, denoted as the solubilization index (SI). Nine isolates that exhibited P-solubilization potential with an SI ranging from 1.19 to 2.76 were genetically characterized as five yeasts belonging to the genus Saccharomyces cerevisiae and four non-Saccharomyces, based on a PCR analysis of the ITS1-26S region amplied by SC1/SC2 species-specific primers. The highest P-solubilization efficiency was demonstrated by isolate PSY- 4, which was identified as Saccharomyces cerevisiae by a sequence analysis of the variable D1/D2 domain of the 26S rDNA. The effects of single and mixed inoculations with yeast PSY-4 and Bacillus polymyxa on the P-uptake and growth of corn were tested in a greenhouse experiment using different levels of a phosphorus chemical fertilizer (50, 100, and 200 kg/ha super phosphate 15.5% $P_2O_5$). The results showed that inoculating the corn with yeast PSY-4 or B. polymyxa caused significant increases in the shoot and root dry weights and P-uptake in the shoots and roots. The P-fertilization level also had a significant influence on the shoot and root dry weights and P-uptake in the shoots and roots when increasing the P-level from 50 up to 200 kg/ha. Dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 200 kg/ha gave higher values for the shoot and root dry weights and P-uptake in the shoots and roots, yet these increases were nonsignificant when compared with dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 100 kg/ha. The best increases were obtained from dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 100 kg/ha, which induced the following percentage increases in the shoot and root dry weights, and P-uptake in the shoots and roots; 16.22%, 46.92%, 10.09%, and 31.07%, respectively, when compared with the uninoculated control (fertilized with 100 kg/ha).

• 한국균학회지
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• 제41권4호
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• pp.218-224
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• 2013

한국 전통 발효식품에서 분리한 효모로부터 인산 가용화 활성이 우수한 5균주를 선발하였다. 선발한 균주 중 2균주는 Pichia anomala로 동정되었고, 3균주는 각각 Pichia farinosa, Candida versatilis, Pichia subpelliculosa로 동정되었다. 인산 가용화 효모는 $20{\sim}35^{\circ}C$의 온도에서 잘 자라는 중 온성 효모였으며 P. farinosa Y669는 $45^{\circ}C$의 고온에서도 생장하였다. C. versatilis Y907 균주는 pH 5~6의 좁은 pH 범위에서 생장하였고 15%의 NaCl 농도까지 내성을 나타내는 호염성 균주였다. 그 외 4균주는 pH 4.0~8.0에서 생장하였으며 NaCl 10% 농도에서 내성을 나타내었다. 인산 가용화 균주는 토양에서도 8주 동안 $10^7{\sim}10^8$ cfu/g의 밀도를 유지하며 생존하였다. 분리균주 중 인산 가용화 활성은 P. subpelliculosa Y1101가 가장 우수하였으며 배양 11일 후 697.2 ug/mL의 유리인산을 생성하였다.

• 한국식품영양과학회지
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• 제22권3호
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• pp.359-366
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• 1993

Molds are eucaryotic, multicellular, multinucleate, filamentous organisms that reproduce by forming asexual and sexual spores. The spores are readily spread through the air and because they are very light-weight and tend to behave like dust particles, they are easily disseminated on air currents. Molds therefore are ubiquitous organisms that are found everywhere, throughout the environment. The natural habitat of most molds is the soil where they grow on and break down decaying vegetable matter. Thus, where there is decaying organic matter in an area, there are often high numbers of mold spores in the atmosphere of the environment. Molds are common contaminants of plant materials, including grains and seeds, and therefore readily contaminate human foods and animal feeds. Molds can tolerate relatively harsh environments and adapt to more severe stresses than most microorganisms. They require less available moisture for growth than bacteria and yeasts and can grow on substrates containing concentrations of sugar or salt that bacteria can not tolerate. Most molds are highly aerobic, requiring oxygen for growth. Molds grow over a wide temperature range, but few can grow at extremely high temperatures. Molds have simple nutritional requirements, requiring primarily a source of carbon and simple organic nitrogen. Because of this, molds can grow on many foods and feed materials and cause spoilage and deterioration. Some molds ran produce toxic substances known as mycotoxins, which are toxic to humans and animals. Mold growth in foods can be controlled by manipulating factors such as atmosphere, moisture content, water activity, relative humidity and temperature. The presence of other microorganisms tends to restrict mold growth, especially if conditions are favorable for growth of bacteria or yeasts. Certain chemicals in the substrate may also inhibit mold growth. These may be naturally occurring or added for the purpose of preservation. Only a relatively few of the approximately 100,000 different species of fungi are involved in the deterioration of food and agricultural commodities and production of mycotoxins. Deteriorative and toxic mold species are found primarily in the genera Aspergillus, Penicillium, Fusarium, Alternaria, Trichothecium, Trichoderma, Rhizopus, Mucor and Cladosporium. While many molds can be observed as surface growth on foods, they also often occur as internal contaminants of nuts, seeds and grains. Mold deterioration of foods and agricultural commodities is a serious problem world-wide. However, molds also pose hazards to human and animal health in the form of mycotoxins, as infectious agents and as respiratory irritants and allergens. Thus, molds are involved in a number of human and animal diseases with serious implication for health.