• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.800-805
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• 2007

Two endoglucanases with processive cellulase activities, produced from Fomitopsis palustris grown on 2% microcrystalline cellulose(Avicel), were purified to homogeneity by anion-exchange and gel filtration column chromatography systems. SDS-PAGE analysis indicated that the molecular masses of the purified enzymes were 47 kDa and 35 kDa, respectively. The amino acid sequence analysis of the 47-kDa protein(EG47) showed a sequence similarity with fungal glycoside hydrolase family 5 endoglucanase from the white-rot fungus Phanerochaete chrysosporium. N-terminal and internal amino acid sequences of the 35-kDa protein(EG35), however, had no homology with any other glycosylhydrolases, although the enzyme had high specific activity against carboxymethyl cellulose, which is a typical substrate for endoglucanases. The initial rate of Avicel hydrolysis by EG35 was relatively fast for 48 h, and the amount of soluble reducing sugar released after 96 h was $100{\mu}g/ml$. Although EG47 also hydrolyzed Avicel, the hydrolysis rate was lower than that of EG35. Thin layer chromatography analysis of the hydrolysis products released from Avicel indicated that the main product was cellobiose, suggesting that the brown-rot fungus possesses processive EGs capable of degrading crystalline cellulose.

• Mycobiology
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• v.43 no.2
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• pp.131-136
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• 2015

The basidiomycete Laetiporus sulphureus var. miniatus belongs to the Aphyllophorales, Polyporaceae, and grows on the needleleaf tree. The fruiting bodies of Laetiporus species are known to produce N-methylated tyramine derivatives, polysaccharides, and various lanostane triterpenoids. As part of our ongoing effort to discover biologically active compounds from wood-rotting fungi, an anti-inflammatory triterpene, LSM-H7, has been isolated from the fruiting body of L. sulphureus var. miniatus and identified as acetyl eburicoic acid. LSM-H7 dose-dependently inhibited the NO production in RAW 264.7 cells without any cytotoxicity at the tested concentrations. Furthermore it suppressed the production of proinflammatory cytokines, mainly inducible nitric oxide synthase, cyclooxygenase-2, interleukin (IL)-$1{\beta}$, IL-6 and tumor necrosis factor ${\alpha}$, when compared with glyceraldehyde 3-phosphate dehydrogenase. These data suggest that LSM-H7 is a crucial component for the anti-inflammatory activity of L. sulphureus var. miniatus.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.844-851
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• 2010

Controlling the dissolved oxygen (DO) in the fed-batch culture of the medicinal mushroom Ganoderma lucidum led to a 2-fold increase of the maximum biomass productivity compared with uncontrolled DO conditions. By contrast, extracellular polysaccharide (EPS) production was two times higher under oxygen limitation (uncontrolled DO) than under increased oxygen availability (controlled DO). Morphologically, dispersed mycelium was predominant under controlled DO conditions, with highly branched hyphae, consistent with the enhanced culture growth noted under these conditions, whereas in the uncontrolled DO process mycelial clumps were the most common morphology throughout the culture. However, in both cultures, clamp connections were found. This is an exciting new finding, which widens the applicability of this basidiomycete in submerged fermentation. In rheological terms, broths demonstrated shear-thinning behavior with a yield stress under both DO conditions. The flow curves were best described by the Herschel-Bulkley model: flow index down to 0.6 and consistency coefficient up to 0.2 and 0.6 Pa $s^n$ in uncontrolled and controlled cultures DO, respectively. The pseudoplastic behavior was entirely due to the fungal biomass, and not to the presence of EPS (rheological analysis of the filtered broth showed Newtonian behavior). It is clear from this study that dissolved oxygen tension is a critical process parameter that distinctly influences G. lucidum morphology and rheology, affecting the overall performance of the process. This study contributes to an improved understanding of the process physiology of submerged fermentation of G. lucidum.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.774-780
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• 2009

Flammulina velutipes is a popular edible basidiomycete mushroom found in East Asia and is commonly known as winter mushroom. Mushroom development showing dramatic morphological changes by different environmental factors is scientifically and commercially interesting. To create a genetic database and isolate genes regulated during mushroom development, cDNA libraries were constructed from three developmental stages of mycelium, primordium, and fruit body in F. velutipes. We generated a total of 5,431 expressed sequence tags (ESTs) from randomly selected clones from the three cDNA libraries. Of these, 3,332 different unique genes (unigenes) were consistent with 2,442 (73%) singlets and 890 (27%) contigs. This corresponds to a redundancy of 39%. Using a homology search in the gene ontology database, the EST unigenes were classified into the three categories of molecular function (28%), biological process (29%), and cellular component (6%). Comparative analysis found great variations in the unigene expression pattern among the three different unigene sets generated from the cDNA libraries of mycelium, primordium, and fruit body. The 19-34% of total unigenes were unique to each unigene set and only 3% were shared among all three unigene sets. The unique and common representation in F. velutipes unigenes from the three different cDNA libraries suggests great differential gene expression profiles during the different developmental stages of F. velutipes mushroom.

• The Korean Journal of Mycology
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• v.12 no.1
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• pp.35-43
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• 1984

To produce and characterize antineoplastic constituents in the submerged cultured­mycelia of Laccaria laccata, the mycelia were extracted with distilled water. Purification of the extract was carried out by acetone precipitation, by ion exchange chromatography using DEAE­Sephadex A-50, CM-Sephadex C-25 resins, and by gel filtration chromatography on Sephadex G-200. Each fraction obtained during the purification was examined for antineoplastic activity against sarcoma 180 in ICR mice. As the purification proceeded, the antineoplastic activity was markedly increased. The highly purified Fraction E showed 75% tumor inhibition ratio at a dose of 10mg/kg/day and contained 81% polysaccharide and 4% protein. The antitumor component of Fraction E stimulated an accumulation of peritoneal exudate cells including peritoneal macrophages, and is named laccaran.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.157-163
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• 1991

The cultural conditions in shake flasks were investigated under which maximum amounts of laccase produced by a strain of white-rot fungus Coriolus versicolor CV3. The enzyme yields on potato-malt extract medium by the fungus were higher than on other media consisted of onion infusion or malt extract, with maximum activity of $1.50unit/m{\ell}$ culture or 119.5 unit/g mycelium at 11 days of incubation. Maximum yields of laccase and growth were obtained by supplementation of yeast extract or potassium nitrate to the potato-malt extract medium. Addition of 2.5-xylidine at $4{\times}10^{-4}M$ concentration to the medium induced the laccase production 3.1-fold higher than the basal level, while the mycelial growth was somewhat repressed. The pH optimum for the growth and laccase formation by the fungus was between pH 4 to 4.5.

• Journal of Mushroom
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• v.9 no.1
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• pp.3-16
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• 2011

In the bipolar basidiomycete Pholiota nameko, a pair of homeodomain protein genes located at the A mating-type locus regulates mating compatibility. In the present study, we used a DNA-mediated transformation system in P. nameko to investigate the homeodomain proteins that control the clamp formation. When a single homeodomain protein gene (A3-hox1 or A3-hox2) from the A3 monokaryon strain was introduced into the A4 monokaryon strain, the transformants produced many pseudo-clamps but very few clamps. When two homeodomain protein genes (A3-hox1 and A3-hox2) were transformed either separately or together into the A4 monokaryon, the ratio of clamps to the clamp-like cells in the transformants was significantly increased to approximately 50%. We, therefore, concluded that the gene dosage of homeodomain protein genes is important for clamp formation. When the sip promoter was connected to the coding region of A3-hox1 and A3-hox2 and the fused fragments were introduced into NGW19-6 (A4), the transformants achieved more than 85% clamp formation and exhibited two nuclei per cell, similar to the dikaryon (NGW12-163 ${\times}$ NGW19-6). The results of real-time RT-PCR confirmed that sip promoter activity is greater than that of the native promoter of homeodomain protein genes in P. nameko. So, we concluded that nearly 100% clamp formation requires high expression levels of homeodomain protein genes and that altered expression of the A mating-type genes alone is sufficient to drive true clamp formation.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.49-59
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• 1986

To examine safety of Ganoderma lucidum, it was extracted with hot water (Fraction A). After the extract was dialyzed and freeze-dried, a polysaccharide fraction (Fraction B) was obtained and examined for acute and subacute toxicity. In the acute toxicity tests of Fr. A and Fr. B on mice, both agents did not show any serious and lethal effects. The results showed that 50% lethal doses were higher than 5,000 mg/kg. The experiments of oral administration of Fr. A (5,000 mg/kg) to mice for 30 days showed that there were no changes in body weight, hematological features and organ weight.

• The Korean Journal of Mycology
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• v.11 no.4
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• pp.151-157
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• 1983

To find antitumor components in Korean basidiomycetes, the carpophores of Armillariella mellea which were collected in Gyeong Gi Province were extracted with distilled water at $90{\sim}100^{\circ}C$ for eight hours. The hot water extract was concentrated under reduced pressure, mixed with three-fold volumes of ethanol and allowed to stand at $4^{\circ}C$ overnight. The precipitate was centrifugated and lyophilized to yield a protein-polysaccharide fraction. It was examined for antitumor activity against sarcoma 180 implanted in ICR mice. The fraction showed 75.7%, 83.9%, and 94.1% of tumor inhibition ratios at the doses of 10, 20 and 50 mg/kg/day, respectively. The chemical analysis of the fraction showed that it contained a polysaccharide(41.3%) and a protein (35.0%). The hydrolyzates of the polysaccharide moiety contained fucose (4.5%), xylose (1.1%), galactose (17.4%), glucose (55.4%), mannose(19.4%), and one unknown monosaccharide. The protein moiety contained seventeen amino acids. The protein-polysaccharide from A. mellea was administered, i.p., to mice and caused an influx of polymorphonuclear leukocytes (PMN) at $5{\sim}24$ hours which was followed by an accumulation of macrophages and disappearance of the PMN at $48{\sim}72$ hours.

• The Korean Journal of Mycology
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• v.38 no.1
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• pp.1-4
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• 2010

Orchid mycorrhizal fungi(OMF) were examined in roots of the two threatened orchid species, Cypripedium japonicum and C. macranthum. The morphological characteristics of mycorrhizal colonization in the roots of two orchid species were observed. OMF colonized in the roots of two species were identified using molecular analysis. DNA from the root was extracted and amplified internal transcribed spacer(ITS) region using basidiomycete ITS primers, ITS1-OF and ITS4-OF. Four species belonging to Tulasnellaceae in roots of C. japonicum and two species of Tulasnellaceae and one basidiomycetous species was found in roots of C. macranthum.