• Journal of Forest and Environmental Science
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• 제31권4호
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• pp.312-316
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• 2015

Rhizina undulata, the causal agent of Rhizina root rot, is a soil-borne fungus occurring on coniferous trees. The destruction of coastal forests caused by R. undulata infection has been mainly associated with bonfires at camping sites. However, Rhizina root rot was observed in the western coastal forests without fire. It was hypothesized that Rhizina root rot in this area might be closely related to the soil salinity, which can facilitate the growth and survival of R. undulata. So, the variation in sodium chloride (NaCl) resistance among isolates of Rhizina undulata was compared using liquid media containing different concentrations of NaCl ranging from 0 mM to 300 mM. Our results showed that, albeit of no growth at a higher concentration of NaCl (300 mM), most of R. undulata isolates were capable of germinating and grew at up to 100 mM, indicating that NaCl resistance varies among R. undulata isolates. It was further found that isolates from coastal areas seemed to be more tolerant to NaCl than those further away the coast. We demonstrated that R. undulata could be possible to survive in coastal areas, but was lower NaCl tolerance than other fungi.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.661-667
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• 1999

The effect of fungal elicitor and heavy metal salts on the production of flavonol glycosides in cell cultures of Ginkgo biloba was investigated. Among the fungi tested, Trichoderma longibrachiatum ATCC 52326 was found to be the most efficient in the production of flavonol glycosides. Kaempferol production from the elicited callus increased ten-fold as compared to the unelicited callus, while quercetin concentration of elicited cells was nine-fold higher than that of uneliceited cells in suspension cultures. The maximum quercetin concentration of 0.362㎎/l was obtained in 1.25㎎/l of the homogenate elicitor. Among the heavy metal salts tested, CuSO₄ showed a significant effect on quercetin accumulation, reaching to the concentration of 0.526 ㎎/l. Quercetin concentration increased to a maximum of l2-fold in response to CuSO₄ treatment as compared to that of untreated cells. The phenylalanine ammonia-lyase (PAL) activity and flavonol glycosides production simultaneously increased for 5 days of culture after fungal elicitor feeding, and their contents showed the same proportional patterns during the culture period. In contrast, PAL activity of cell cultures treated with CuSO₄ was almost constant during the culture period, although quercetin production increased remarkably.

• 한국미생물·생명공학회지
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• 제13권3호
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• pp.173-178
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• 1985

Ganoderma lucidum (영지)의 액체 배양물로부터 전분을 강력하게 분해하는 amylase를 조정제하여 이 효소의 기본적인 성질을 조사하였다. 이 효소의 최적작용 pH와 온도는 각각 5.5, 5$0^{\circ}C$였고 pH 및 열처리에 상당히 불안정한 효소였으며 activation energy는 7.06Kcal/mole이였다. M $n^{++}$, $Ca^{++}$ 및 C $u^{++}$에 의해서 효소활성이 증가되었으나 H $g^{++}$ A $g^{+}$에 의해서 효소활성이 저해되었으며 여러 가지 chemical reagents에 의해서는 영향을 받지 않았다. Soluble starch, amylose, amylopectin 및 glycogen에 대한 Km 치는 0.16, 0.37, 0.19 및 0.16mg/$m\ell$ 였으며 각종기질에 대한 분해능력을 조사한 결과 열처리를 받은 전분류는 분해할 수 있었으나 생전분은 그 분해속도가 느렸다. Maltose에 의해서 효소활성이 저해되었으며 maltose의 저해양상은 competitive inhibition을 나타내었다.

• 한국식품영양과학회지
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• 제24권6호
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• pp.964-969
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• 1995

섬유성 biomass의 효율적인 이용을 위하여 CMCase, avicelase 분비력이 높은 균주(A. wentii MAW-598)와 ${\beta}-glucosidase$ (A. niger MAN-831) 분비력이 우수한 균주의 포자를 이용한 원형질세 형성.재생조건 및 융합을 실시하였다. 원형질체 형성 및 재생의 최적조건은 5일 성숙한 포자를 $30\mu\textrm{g}/ml$ 농도의 2-DG로 4시간 전배양하여 0.7M KCI 삼투압 안정제, novozyme(7.5mg/ml)+driselase(2.5mg/ml) 혼합효소로 5시간 반응시키는 것이 효과적이었다. 원형질체 융합 조건은 $CaCl_2$ 15mM, 25% PEG 4000, pH 5-7, $36^{\circ}C$에서 25~30분간 처리하였을때 효과적이었으며, 융합빈도는 $7.94\;{\times}\;10^{-4}$로 나타났다. FA-208 융합주는 친주에 비하여 각각 1.5, 1.3, 1.2배 효소활성의 증가를 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제5권2호
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• pp.323-327
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• 1992

An experiment was conducted to determine whether there were any apparent differences in the microbial population, colonization pattern and digestion of guinea grass in situ, between cattle and swamp buffalo. Percentage losses in dry matter (DM), nitrogen (N) and neutral detergent fibre (NDF) of guinea grass were significantly (p<0.01) higher when incubated in the rumen of buffalo than in cattle. Buffalo also showed significantly (p<0.05) faster degradation rates than cattle for each grass component (DM, N, DNF). Light microscopy and SEM examination of the incubated grass materials showed that there were no apparent differences in the pattern of bacterial and fungal invasion and colonization of the grass materials between cattle and buffalo. Attachment of bacteria and fungal zoospores on the grass fragments occurred at 15 min after rumen incubation. After 3 h of rumen incubation, dense population of bacteria was observed in the thin-walled mesophyll and parenchyma tissues, whereas root-like fungal rhizoids were observed in both thin-walled and thick-walled cells. By 6 h, eroded zones were apparent in the thin-walled tissues and in thick-walled tissues with profuse rhizoids. After 24. 48 and 72 h of rumen incubation, most thin-walled tissues were degraded leaving mostly the thick-walled tissues. The predominant bacteria were the curved rods resembling Butyrivibrio sp., the thick rods resembling Fibrobacter sp., the diplococcoids resumbling Ruminococcus sp. And spirochetes. Fungi were predominantly those with spherical or oval sporangia. Fusiform sporangia with acuminate apices which resembled Ruminomyces sp. Were of lesser occurrence. Few protozoa were found on the grass fragments at all incubation times.

• 한국균학회지
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• 제36권2호
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• pp.116-122
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• 2008

유기성폐기물의 연속적인 시용이 토양내 진균의 밀도에 미치는 영향을 조사한 결과, 진균밀도는 화학비료가 처리된 대조구에 비해 생활하수오니, 공단하수오니, 피혁오니, 주정오니 처리구에서 높게 나타났다. 폐기물 처리 토양에서 분리된 진균은 Penicillium, Trichoderma, Gliocladium, Blastomyces, Phoma 등으로 동정되었다. 폐기물과 중금속이 토양내 진균밀도에 미치는 영향을 분석하기 위해 분리균주를 폐기물과 중금속이 첨가된 배지에 $25^{\circ}C$에서 7일 배양하여 조사한 결과, 선발 진균의 균총생육은 첨가된 폐기물과 중금속에 따라 다양하게 나타났다. 이러한 배양특성은 농경지에 유입되는 오염물질의 생물학적 위해성 평가를 위한 기초자료로 이용될 수 있을 것으로 사료된다.

• 한국식품영양과학회지
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• 제29권4호
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• pp.624-628
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• 2000

측백에 함유 된 히노키티올의 천연 보존료로서의 이용 가능성을 검토하고자 측백 히노키티올 추출물을 식빵 제조시 이용하여 self-life 연장효과 및 품질특성을 조사하였다. 측백에 함유된 히노키 티올은 수증기 증류로 추출했을 때 측백잎에서 12.06mg/100gdldjt고 측백열매 꼬투리에서 13.78mg/100g이었다. 측백 히노키티올 추출물은 식방의 저장 중 수분이나 pH에는 큰 영향 을 주지 못하였으나, 세균 중식 및 곰팡이 생성에는 억제효과를 보였다. 측백잎 50g 추출물 (히나키티올 함량 6.03mg)을 첨가한 식빵은 저장 2일까지 세균이 전혀 자라지 못하였으며 세균수가 104CUF/g 수준에 도달하는데 4일 걸렸다. 또한 곰팡이 생성은 대조구가 저장 3일 째에 관찰되었으나 측백잎 50g 추출물을 첨가한 것은 5일째 관찰되었다. 식빵의 관능적 품 질은 측백 히노키티올 추출물 첨가로 인하여 그다지 영향을 받지 않았다. 이러한 결과는 식 빵 제조시 식빵 제조시 히노키티올 추출물을 이용하면서 식빵의 shelf-life을 연장시킬 수 있음을 보여 주었다.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.658-664
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• 2004

To find a new utilization of rice bran, nine higher fungi were examined for the production of exo-biopolymer with macrophage stimulating activity from rice bran. Among the exo-biopolymers produced from submerged cultures, Lentinus edodes showed the highest activity, followed by Grifola frondosa, Schizophyllum commune, and Coriolus versicolor. L. edodes also had the most potent macrophage stimulating activity in a liquid culture rather than in a solid culture. In order to improve rice bran utilization and the yield of exo-biopolymer with macrophage stimulating activity, the treatment of Rapidase effectively increased the macrophage stimulating activity (about 30% increase), whereas the other enzymes (Econase, Viscozyme, Ultraflo, Celluclast, and Thermylase) treatments did not increase the macrophage stimulating activity. Exo-biopolymer with macrophage stimulating activity from L. edodes contained mainly neutral sugars (58.7%) with considerable amounts of uronic acid (32.2%) and a small amount of proteins (9.1%). Component sugars of exo-biopolymer consisted of mainly arabinose, galactose, glucose, mannose, and xylose (0.95:0.81:0.96:1.00:0.39, respectively). When the exo-biopolymer was treated with $NaIO_4, NaClO_2$, and pronase, the $NaClO_2$ treatment and pronase digestion had little effect, whereas $NaIO_4$ oxidation significantly decreased the macrophage stimulating activity (47.6% reduction at $100\mug/ml$). Therefore, the carbohydrate moiety in exo-biopolymer from L. edodes plays an important role in the expression of the macrophage stimulating activity.

• 대한바이러스학회지
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• 제30권1호
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• pp.61-70
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• 2000

Standard plaque assay using agarose-overlay has long been used for titration of many infectious virus particle. Plaque assay for the titration of varicella-zoster virus and its live vaccine requires three intermittent agarose overlay to visualize plaques. Overall procedure of the assay takes at least nine days from virus inoculation and microbe contamination including fungi is frequently accompanied during incubation period. We studied whether an immunofocus assay in conjunction with peroxidase-mediated immunohistochemical reaction may replace the standard plaque assay for the virus titration by comparing the two methods. A linear relationship was observed between number of foci and virus dilution. The number of foci in a given dilution of virus appeared a little higher than counted plaques formed in standard plaque assay. Independent titration results obtained from two assay methods for a given dilution of virus demonstrated a strong correlation ($r^2=0.99$). Foci of virus infected cells as revealed by the enzyme reaction could be counted either 4 days post-infection (p.i.) under low magnification (40X) microscopy, or 6 days p.i. by naked eye observation. Larger size of cell cuture plate, virus adsorption at $35^{\circ}C$, and 10% FBS in diluent appeared to be better conditions for the assay. Immunofocus assay will be an effective and dependable titration method for varicella-zoster virus and its live vaccine in place of the standard plaque assay in respect to accuracy, costs, and experimental convenience.

• Biomolecules & Therapeutics
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• 제20권5호
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• pp.433-445
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• 2012

During the course of evolution, animals encountered the harmful effects of fungi, which are strong pathogens. Therefore, they have developed powerful mechanisms to protect themselves against these fungal invaders. ${\beta}$-Glucans are glucose polymers of a linear ${\beta}$(1,3)-glucan backbone with ${\beta}$(1,6)-linked side chains. The immunostimulatory and antitumor activities of ${\beta}$-glucans have been reported; however, their mechanisms have only begun to be elucidated. Fungal and particulate ${\beta}$-glucans, despite their large size, can be taken up by the M cells of Peyer's patches, and interact with macrophages or dendritic cells (DCs) and activate systemic immune responses to overcome the fungal infection. The sampled ${\beta}$-glucans function as pathogen-associated molecular patterns (PAMPs) and are recognized by pattern recognition receptors (PRRs) on innate immune cells. Dectin-1 receptor systems have been incorporated as the PRRs of ${\beta}$-glucans in the innate immune cells of higher animal systems, which function on the front line against fungal infection, and have been exploited in cancer treatments to enhance systemic immune function. Dectin-1 on macrophages and DCs performs dual functions: internalization of ${\beta}$-glucan-containing particles and transmittance of its signals into the nucleus. This review will depict in detail how the physicochemical nature of ${\beta}$-glucan contributes to its immunostimulating effect in hosts and the potential uses of ${\beta}$-glucan by elucidating the dectin-1 signal transduction pathway. The elucidation of ${\beta}$-glucan and its signaling pathway will undoubtedly open a new research area on its potential therapeutic applications, including as immunostimulants for antifungal and anti-cancer regimens.