• Korean Journal of Microbiology
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• v.38 no.4
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• pp.230-230
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• 2002

Class Ⅲ chitin synthases in filamentous fungi are important for hyphal growth and differentiation of several filamentous fungi. A genomic clone containing the full gene encoding Chs4, a class Ⅲ chitin synthase in Penicillium chrysogenum, was cloned by PCR screening and colony hybridization from the genomic library. Nucleotide sequence analysis and transcript mapping of chs4 revealed an open reading frame (ORF) that consisted of 5 exons and 4 introns and encoded a putative protein of 915 amino acids. Nucleotide sequence analysis of the 5′flanking region of the ORF revealed a potential TATA box and several binding sites for transcription activators. The putative transcription initiation site at -716 position was identified by primer extension and the expression of the chs4 during the vegetative growth was confirmed by Northern blot analysis. Amino acid sequence analysis of the Chs4 revealed at least 5 transmembrane helices and several sites for past-transnational modifications. Comparison of the amino acid sequence of Chs4 with those of other fungi showed a close relationship between P chrysogenum and genus Aspergillus.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.724-731
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• 1988

For a study on the production of ${\gamma}-linolenic$ acid(GLA) by microorganisms, fifteen strains of Mucorales obtained from culture stocks and ten isolate strains were compared in their cell growth, lipid content, fatty acid composition and pellet size formed in shake flask culture. Among the fungi examined, the isolated fungus, designated as FB-354, was found to be the most suitable one for the production of GLA mainly due to its high contents of lipid, 29.9% of dry cell weight and GLA, 16.8% of the total fatty acids. The strain FB-354 was tentatively identified as Mucor sp. on the basis of morphological characteristics. Fungal oil produced by Mucor sp. FB-354 was fractionated into 81.1% of neutral lipid, 7.2% of glycolipid, and 11.8% of phospholipid. Although the GLA content in the phospholipid fraction was as high as 21.4%, most of the GLA was found in the neutral lipid fraction.

• Journal of Integrative Natural Science
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• v.7 no.3
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• pp.173-182
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• 2014

To simplify the different biological investigation of the methanolic extract and solvent-solvent partitioning of Lablab purpures (L. purpures) bark. In-vitro anti-oxidant study was determined using total DPPH radical scavenging assay. In vitro antimicrobial study was measured by observing zone of inhibition. The cytotoxic activity was studied using brine shrimp lethality bioassay and thrombolytic activity by clot disruption method. The antioxidant potential was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Folin-Ciocalteau reagents using butylated hydroxytolune (BHT) and ascorbic acid as standards. The Aqueous soluble fraction revealed the highest free radical scavenging activity ($IC_{50}=48.76{\mu}g/mL$). The antimicrobial screening of the bark of L. purpures exhibited mild to moderate activity in test microorganisms. The CSF showed the maximum relative percentage inhibition against Salmonella parathyphi (34.2%) for bacteria and C. albicans (28.8%) for fungi whereas, lowest relative percentage inhibition against Sarcina lutea (22.0%) for bacteria and Aspergillus niger (24.4%) for fungi. In the brine shrimp lethality bioassay, The $LC_{50}$ values of Carbon tetrachloride and N-Hexane soluble fraction were found $92.18{\mu}g/mL$, and $68.95{\mu}g/mL$ respectively while the $LC_{50}$ values of standard Vincristine sulphate was $1.37{\mu}g/mL$. The methanolic extract and its organic soluble fractions of Lablab purpureus at concentration 2.0 mg/mL, significantly protected the lysis of erythrocyte membrane induced by hypotonic solution and heat as compared to the standard, acetyl salicylic acid (0.10 mg/mL). The MSF and AQSF produced 61.48 % and 53.75% inhibition of hemolysis of RBC caused by hypotonic solution respectively, whereas acetyl salicylic acid (0.10 mg/mL) showed 76.42%. Ethanol extract of L. purpures and all of its different partitions exhibited moderate thrombolytic activity of 37.25%-2.40%. Very good preliminary screening and simplified experiments were able to show the different biological activity of methanolic extract and its soluble fractions of L. purpures at a time.

• The Journal of the Korean Society for Microbiology
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• v.10 no.1
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• pp.39-58
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• 1975

These studies were carried out to detect the presence of mycotoxin producing fungi in various kind of grains and foodstuffs in Korea. The experiments were divided into three parts: bacteriologic, toxicologic and electron microscopic studies. The results were summarized as follows: 1. From the 133 various samples, 426 colonies of fungi were isolated. In 405 of 426 colonies, it was possible to identify 17 genera. Among the identified strains, the predominant genera were Penicillium, Aspergillus and Alternaria. 2. In cytotoxicity test, 20 strains showed mild to severe toxic effects in mice and 24 strains showed toxic effects on HeLa cells among the 107 strains of experiments. 3. In electron microscopic studies of liver cells from animal which had been treated with toxin like substances, the liver cells showed the cytoplasmic changes: dilatation of endoplasmic reticulum, swelling of mitochondria, disappearance of mitochondrial cristae, increased number of lipid and glycogen particles. Nucleus and nuclear envelope alterations were also noted. 4. In fine structure of HeLa cells treated with culture filtrates of mycotoxin producing fungi and experimental strains had been noted a certain specific changes induced by culture filtrates. These alterations showed the disappearance of golgi complex, endoplasmic reticulum vacuolization and mitochondrial changes. 5. As a mass screening, the cytotoxicity tests of HeLa cells and histopathologic study of mice liver cells treated with toxin-like substances, employed are feasible to detect mycotoxin producing fungi.

• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1744-1749
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• 2010

The role of endophytic fungi in plant growth and development is well documented. However, endophytic fungi with growth promotion capacity have never been isolated from weeds previously. In the current study, we isolated 8 fungal endophytes from the roots of Monochoria vaginalis, a serious weed of rice paddy in Korea. These isolates were screened on Waito-C, in order to identify plant growth promoting metabolites. Two fungal isolates (M5.A & M1.5) significantly promoted the plant height and shoot length of Waito-C during preliminary screening experiments. The culture filtrates (CFs) of M5.A and M1.5 also promoted the shoot length of Echinocloa crusgalli. Gibberellins (GAs) analysis of the CFs of M5.A and M1.5 showed that these endophytic fungi secrete higher quantities of GAs as compared with wild-type G. fujikuroi KCCM12329. The CF of M5.A contained bioactive GAs ($GA_3$, 2.8 ng/ml; $GA_4$, 2.6 ng/ml, and $GA_7$, 6.68 ng/ml) in conjunction with physiologically inactive $GA_9$ (1.61 ng/ml) and $GA_{24}$ (0.18 ng/ml). The CF of M1.5 contained physiologically active GAs ($GA_3$, 1.64 ng/ml; $GA_4$, 1.37 ng/ml and $GA_7$, 6.29 ng/ml) in conjunction with physiologically inactive $GA_9$ (3.44 ng/ml), $GA_{12}$ (0.3 ng/ml), and $GA_{24}$ (0.59 ng/ml). M5.A and M1.5 were identified as new strains of Penicillium sp. and Aspergillus sp., respectively, based on their 18S rDNA sequence homology and phylogenetic analysis.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.135-135
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• 1998

To find an antagonist of Pythium ultimum, the causal agent of damping-off, numerous actinomycete strains were screened for in vitro inhibiting mycelial growth of the target fungus and producing bioactive metabolites. A strain identified as Streptomyces sp. G60655 was isolated and used for further antagonistic efficacy. The degree of antagonism between the fungus and G60655 was affected by the medium used. Furthermore, the preinoculation of the antagonist was found to be necessary to exhibit the maximum efficacy of antagonsim against the fungus. From the culture broth, a bioactive metabolite was detected and purified by solvent extraction, silica gel chromatography and preparative HPLC. The FAB-MS spectrum of the active compound showed a molecular ion peak at m/z 1101 (M + H)$\^$+/, suggesting the molecular weight of 1100. The UV absorptions at 242 and 323 nm indicated the presence of aromatic functions. The structure of this compound was identified as echinomycin, a depsipeptide antibiotic by spectroscopic studies including various NMR measurements. Echinomycin was inactive against several soil born fungi, but inhibited the mycelial growth of P. ultimum and its related oomycetous fungi.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.78-85
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• 1998

During the screening of biological control agents for insect pests in the greenhouse, 70 dead insect-related fungi were isolated and tested insecticidal effect of their culture filtrates was tested. From this studies, CNAB-63 isolate showed strong control effects against the cotton aphids and the two-spotted spider mite as 65.19% and 77.55%, respectively. The insecticidal active compound of CNAB-63 isolate was purified from culture filtrate by silica gel chromotography, thin layer chromatography and HPLC. Purified active compound (CNAB) showed control effects against the two-spotted spider mite with 63.45% at $100\;{\mu}g/ml$ concentration. However, it did not exhibit antimicrobial activity against fungi and bacteria.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.20-20
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• 2015

Endophytic fungi are microorganisms inhabiting living plant tissues without causing apparent harm to the host. They are drawing increasing attention due to their ability to produce various bioactive compounds as well as their effects on host growth and resistance to biotic and abiotic stresses. As a first step to assess biodiversity of plant associated fungi in Korea and the following evaluation on diverse biological activities, we are collecting endophytic fungi from plant in wild followed by systematic long-term storage in liquid nitrogen. Molecular identification using ITS sequences was also incorporated for pure culture by hyphal tip isolation. As of April 2015, about 1,400 fungal strains had been isolated from about 170 plant taxa. Fungal isolates belonging to Pleosporales, Diaporthales, Glomerellales, Hypocreales, and Xylariales were the most abundant. These collections are being used for several complementary researches, including screening of isolates with novel bioactive compounds or conferring drought stress resistance, phylogenetic and genomic study. Genome sequencing was performed for 3 isolates, one Xylaria sp. strain JS573 producing griseofulvin, an antifungal compound, and two Fusarium spp. strains JS626 and JS1030, which are assumed to be new species found in Korea. More detailed analysis on these genomes will be presented. These collections and genome informations will serve as invaluable resources for identifying novel bioactive materials in addition to expand our knowledge on fungal biodiversity.

• Journal of Photoscience
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• v.9 no.2
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• pp.421-423
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• 2002

Phellinus linteus mycelia have many pharmacological effects, although their pharmacological efficacy principles have not been known yet. In the course of screening for biological activity of the extracts of Phellinus linteus mycelia, we found strong antioxidative activity in some fraction of water-insoluble. Therefore, we tried to isolate the active principle(s) from the extract. The isolation of the active compound was guided by superoxide anion radical scavenging activity. As a result, caffeic acid was isolated as an active compound. The IC$\_$50/ of the compound was 3.05 $\mu$g/ml (16.9$\mu$M).

• Natural Product Sciences
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• v.13 no.4
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• pp.300-303
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• 2007

Gossypin, a naturally occurring polyhydroxy flavonoid, when subjected to in vitro cytotoxic screening against vero cell lines exhibited 68.75% inhibition at a concentration of $1000{\mu}g$. When tested against five bacteria and five fungi, the flavone derivative showed a moderate activity against Staphylococcus aureus and Escherichia coli, mild inhibition against Pseudomonas aerugenosa and Salmonella typhi and no activity against any of the tested fungi, in the concentrations studied.