• Mycobiology
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• v.28 no.1
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• pp.54-56
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• 2000

A black scab disease occurred on sword bean (Canavalia gladiata) in plastic film houses around Chinju area during the spring season of 1999. The disease started from flower bud, then moved to flower stalk, pod, petiole, cirrus, stem and leaves. The lesions started with small dark brown spots then were gradually expanded. Severely infected plants reached 37.4% of whole plant covered with scab. Numerous conidia were produced on the diseased flower disk, pod, floral axis, stem and leaves. Most of the conidia were appeared to be readily dispersed in the air, but the mycelia were not suggested causing of sooty mold by ectoparasitism. A fungus was isolated from the diseased stem, and inoculated to healthy plants to satisfy the Koch's postulates and proved the fungus was the causal agent of the disease. The isolated fungus grew on potato dextrose agar, forming greenish black to pale brown colonies. Conidia were ellipsoidal, fusiform or subspherical, mostly one-celled but occasionally septated. The conidia were $3.9{\sim}34.1{\times}2.7{\sim}5.1\;{\mu}m$ in size and formed in long branched chains on the erected conidiophores which were pale olivaceous brown and variable in length between $7.2{\sim}210.7\;{\mu}m$ in size. Ramoconidia were $7.6{\sim}29.2{\times}3.2{\sim}14.4\;{\mu}m$ in size. The fungus was identified as Cladosporium cucumerinum based on the above morphological characteristics. The optimum temperature for mycelial growth and conidial formation was about 15 to $25^{\circ}C$. Cladosporium scab of sword bean caused by the fungi has not been reported in Korea previously.

• Mycobiology
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• v.41 no.2
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• pp.94-99
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• 2013

In this study, ethanolic extracts from Hericium erinaceum cultivated with Artemisia capillaris (HEAC) were assessed for their ability to lower the cholesterol levels of male Sprague-Dawley rats fed a high-fat diet. Rats were randomly subdivided into seven test groups. Each group contained eight rats fed a high-fat diet during a growth period lasting 4 wk. Supplementation with the extracts was performed once a day for 2 wk after the high-fat diet. The control group (rats fed a high-fat diet) showed a high efficiency ratio (feed efficiency ratio) value compared to the normal group. Biochemical parameters, including total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-c), and triglyceride (TG) levels dramatically increased in the control group compared to the normal group. High-density lipoprotein-cholesterol (HDL-c) content in the control group was also significantly lower relative to the normal group. Two positive control groups, treated with simvastatin and atorvastatin, had lowered TC, LDL-c, and TG levels, and increased HDL-c content compared to the control group. Treatment with the tested extracts, including HEAC, ethanolic extracts from Hericium erinaceum, and ethanolic extracts from Artemisia capillaris reduced TC, LDL-c, and TG levels and elevated HDL-c content in the hyperlipidemia rats. The atherogenic index and cardiac risk factor values for the HEAC-treated group were 0.95 and 1.95, respectively. Simvastatin- and atorvastatin-treated groups showed atherogenic index values of 1.56 and 1.69, respectively, and cardiac risk factor values of 2.56 and 2.69, respectively. These results show HEAC possesses an ability to cure hyperlipidemia in rats and may serve as an effective natural medicine for treating hyperlipidemia in humans.

• Microbiology and Biotechnology Letters
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• v.45 no.3
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• pp.209-217
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• 2017

In the enduring investigation of the bioactive microbes, Pseudomonas aeruginosa strain (referred to as CGK-KS-1 (ICTB-315)), isolated from Chumathang hot spring, Ladakh, and India, was identified to possess a major bioactive fraction with antimicrobial and anti-biofilm properties. This bioactive metabolite was purified through bioactivity-guided fractionation. The chemical structure of this major compound was elucidated as phenazine-1-carboxamide (PCN) based on $^1H$ and $^{13}C$ NMR, FT-IR, EI-HR-MS and 2D NMR spectroscopic techniques. In the current study, PCN exhibited antimicrobial activity with MIC values ranging between $1.9-3.9{\mu}g/ml$ against various test human pathogens and Xanthomonas spp. PCN showed the anti-biofilm property with the $IC_{50}$ values ranging from 17.04 to $60.7{\mu}M$ against different test pathogens. The in silico docking studies showed PCN strongly interacted with various proteins of different Xanthomonas spp. with high binding energies. We report herein for the first time the anti-biofilm property and the docking studies of PCN. The extrolite from P. aeruginosa strain CGK-KS-1 showed promising bioactivities and may be considered as a potential candidate for application in various biocontrol strategies.

• Mycobiology
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• v.48 no.5
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• pp.410-417
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• 2020

Fungal ecological interactions play a key role in structuring community assemblages. These associations may involve both antagonistic and synergistic relationships, which are commonly influenced by abiotic factors such as nutrient conditions. However, information for extreme, oligotrophic systems remain poor. Herein, interactions among key members of the aquatic transient fungal community (Aspergillus niger, Cladosporium sp., and Coprinellus micaceus) of a low-nutrient freshwater system in the Cuatro Ci enegas Basin, Mexico were studied. Pairwise interaction bioassays were explored in vitro under different nutrient conditions, including carbohydrates-rich, carbohydrates and amino peptides-rich, and low nutrients. Our results indicated that antagonistic patterns prevail among the studied taxa. However, nutrient-dependent changes were observed in Cladosporium sp. shifting to synergy under carbohydrates-rich conditions, suggesting changes in the fungal community composition as a result of nutrient enrichment. Remarkably, our findings contrast with previous work demonstrating mainly synergistic interactions between our tested fungal isolates and co-occurring autochthonous bacteria (Aeromonas spp. and Vibrio sp.) under low-nutrient conditions. This observation may indicate that bacteria and fungi exhibit distinct community-level responses, driven by nutrient conditions. This contributes to the knowledge of fungal community dynamics and interspecific interactions in an oligotrophic ecosystem, highlighting the relevance of nutrient-based shifts and antagonistic interactions in ecosystem dynamics.

• The Korean Journal of Mycology
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• v.22 no.1
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• pp.62-99
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• 1994

The fungal flora of Korean wood-rotting fungi were studied for two years from March of 1990 to February of 1992. Fresh fungi were collected from national parks, local areas, and islands throughout the country. Fleshy fungi of the Aphyllophorales were identified through specimen examination and literature studies. Total 217 species and 1 variety were counted, among which Aleurodiscus cerussatus, Botryobasidium obtusisporum, Ceraceomyces cystidiatus, Erythricium hypnophilum, Grandinia crustosa, Grandinia spathulata, Hyphoderma praetermissum, Hyphoderma roseocremeum, Hypochnicium bombycinum, Hypochnicium detriticum, Hypochnicium lundellii, Laeticorticium roseum, Mycoacia fuscoatra, Peniophora incarnata, Phanerochaete avellanea, Phanerochaete filamentosa, Phanerochaete martelliana, Phlebia lilascens, and Trechispora vaga under the Corticiaceae, Chondrostereum purpureum and Cystostereum subabruptum under the Stereaceae, Tomentella pilosa under the Thelephoraceae, Asterostroma laxum, Hymenochaete cruenta, Hymenochaete fuliginosa, Hymenochaete tabacina, Inonotus radiatus, and Phellinus pomaceus under the Hymenochaetaceae, Antrodia crassa, Antrodia serialis, Ceriporia reticulata, Oligoporus balsameus, Oligoporus guttulatus, Oxyporus cuneatus, Rigidoporus microporus, and Trichaptum laricinum under the Polyporaceae, total 36 species were confirmed as unrecorded species to Korea and are registered here with Korean names and English descriptions.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.105-111
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• 2010

Lentinus lepideus, known as train wrecker fungus, has been used for nutritional and medicinal purposes. Recently, commercial cultivation technique and a new cultivar of the mushroom were developed. To investigate the genetic diversity and phylogenetic relationship for identifying the mushroom strains and cultivar, one commercial and 13 strains of Lentinus lepideus from different geographical regions of Korea were analyzed by ITS regions of rDNA and RAPD of genomic DNA. Three strains of Lentinus edodes were also used for the analysis. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 173 to 179 bp and 203 to 205 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, while the 5.8S sequences were identical with 156 base pairs. A phylogenetic tree based on the ITS region sequences indicated that selected strains could be classified into four clusters, while 3 strains of L. edodes was divided into a new cluster. Ten primers out of 20 arbitrary primers used in the RAPD-PCR efficiently amplified the genomic DNA. The numbers of amplified DNA bands varied with the primers and strains, with polymorphic DNA fragments in the range from 0.2 to 2.6 kb. The results showed that phylogenetic relationship among Korean strains of Lentnus lepideus is high, but genetic diversity is low.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.33-40
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• 2009

From 2006 to 2008, natural habitat of Sparassis crispa were surveyed for investigating ecological conditions at sixteen different sites in Korea. The investigated sites showed very wide altitudinal distribution ranged from 240 meters to 1,100 meters above the sea level. In general, S. crispa showed distinct feature of heart-rot fungi as it occurs on soils around the stems of larch (Larix kaempferi) and Korean white pine (Pinus koraiensis). But it also could be found on stems or on the stumps of dead trees, which indicated that the fungus might have several invasion routes and capabilities to grow on various ecological conditions. All of the sixteen sites were pure stands consisted with conifers such as larch or Korean white pine. The dominant tree layer showed $15.3{\sim}38.0$ meters for tree heights, thicker than twenty centimeters for the diameter at breast height (DBH), and all of them were older than thirty years. Since the stands were pure stand, species diversity of trees in the sites was extremely low. While the dominant tree layer showed only pure coniferous stand, the co-dominant tree layer, shrub layer and herbaceous layer showed more diverse features with higher Shannon-Wiener (H') indices. Soil texture of thirteen sites among sixteen investigated sites were loamy soils, and the contents of organic matter in soil were more or less higher than general forest soils in Korea with $3.79{\sim}14.32%$. The cation exchange capacity (CEC) was also relatively higher than general forest soils with $16.1{\sim}27.2$ cmol+/kg. The data indicated that the cauliflower mushroom occurring sites were relatively fertile than general forest soils. The soils were acidic with pH ranged from 4.2 to 5.2, which were typical features for conifer stands in Korea.

• The Korean Journal of Mycology
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• v.30 no.1
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• pp.50-55
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• 2002

Biological control against mushroom fly, Lycoriella mali, was performed by using Bacillus thuringiensis subsp. israelensis Bti-D and Bti-U, isolated from dead mushroom fly in oyster mushroom houses. Control values of the bacterial strains Bti-D and Bti-U against L. mali in bottle culture of oyster mushroom were 74.4% and 64.2%, respectively, and the value in small tray culture were 75.8% and 56.8%, respectively. In the experiment to develop the mass, cheap media for Bti-D and Bti-U isolates, the Biji broth (bean curd residue, called Biji in Korean language) was selected as a culture medium for an inexpensive and mass cultivation by the measurement of optical density of the two bacteria grown in the different media tested. Insecticidal effect of the formulation contained different ingredients that were prepared by using the Bti-D strain cultured in the Biji broth was tested in tray and bottle culture of oyster mushroom. The WCS formulation that contained corn starch as bio-gel (86.4%) was more effective to control the mushroom fly than living cells (69.1%) in bottle culture of oyster mushroom. Moreover, insecticidal effect of the WCS formulation was improved when water of pH 8 was used for dilution of the formulation. Effect of the WCS formulation using water of pH 8 and chemicals, Zuron (dimillin) W.P. on the control of mushroom fly and the productivity of oyster mushroom was investigated in tray culture of oyster mushroom. The Zuron W.P. was more effective to control the mushroom fly than the WCS formulation. However, compared with no treatment, the productivity of the mushroom treated with the WCS formulation was improved than that of the mushroom with Zuron W.P.

• The Korean Journal of Mycology
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• v.41 no.1
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• pp.21-27
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• 2013

This study was carried out to investigated optimum mixing ratio of Korean natural Acer tegmentosum for production of functional oyster mushroom. Total nitrogen and carbon sources of Acer tegmentosum were 0.2% and 44.4%, respectively and C/N ratio was 234. Total nitrogen source and pH of substrate mixed with Acer tegmentosum were 2.7~2.9 and 4.8~5.0, respectively. The contents of $P_2O_5$, $K_2O$ and MgO at Acer tegmentosum media were higher than that of the control. Mycerial growth was the fastest at Acer tegmentosum 10%, and slower by increase of Acer tegmentosum substrate. Yields of fruiting body was the highest to 159 g/850 mL at 10% of Acer tegmentosum and dimeter and thick of pileus were the highest, too. The L value of pileus and stipes were decreased by increase of Acer tegmentosum substrate, but there was no significant difference in the a-value and the b-value. The contents of $P_2O_5$ and $K_2O$ of fruiting body were increased at Acer tegmentosum substrate, but there was no significant difference in contents of CaO, MgO and $Na_2O$.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.295-306
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• 2018

In the present study, we compared the effects of 50% ethanolic extracts of Chinese and Korean Wolfiporia cocos (CPE and KPE) on in vitro lipid accumulation in 3T3-L1 cells and their anticancer activities in Sarcoma 180 cells. We further compared the anticancer activities and the 50% inhibitory concentrations ($IC_{50}$) of CPE with KPE with cultivated for one and two years in a landfill and a facility (LPE and FPE), respectively. In addition, the single oral dose toxicities of CPE and KPE were evaluated in mice. Lipid accumulation was inhibited after 48 hours, in CPE and KPE treated 3T3-L1 cells; however, no significant difference was observed between CPE and KPE in their lipid accumulation inhibitory activities. The anticancer activity of KPE was higher than that of CPE at $300{\mu}g/mL$ (p<0.05), revealing the possibility of an auxiliary biological means for origin identification. The anticancer activities of LPE and FPE were significantly stronger than that of CPE (p<0.05) but there was no difference between extracts from one- and two-year-old W. cocos, irrespective of the cultivation method. In single oral dose toxicity tests, CPE and KPE did not induce mortality during the 14-day observation. Thus, the 50% of lethal dose ($LD_{50}$) of CPE and KPE were estimated to be higher than 2,000 mg/kg. Taken together, our results indicate that the anticancer assay could be an auxiliary means of identifying the origin of W. cocos. In addition, artificial cultivation could be an alternative way to reduce the import of W. cocos. Lastly, 50% ethanolic W. cocos extracts could be potential candidates for obesity and cancer managements.