• Mycobiology
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• v.47 no.3
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• pp.335-339
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• 2019

Endophytic fungi have the ability to live inside the host plant tissues without causing neither symptoms of diseases/or harm. Opportunistic infections are accountable for majority of the outbreaks, thereby putting a burden on the health system. To investigate and characterize the bioactive compounds for the control of bacteria of clinical importance, extracts from endophytic fungi were isolated from indigenous South African medicinal plants. Extracts from endophytic fungi were isolated from 133 fungal strains and screened against Gram positive and negative bacteria namely Bacillus cereus, Escherichia coli, Enterococcus faecium, and E. gallinarum using disk diffusion. Furthermore, gas chromatography-mass spectrometry was performed to identify the bioactive compounds. Sixteen out of one hundred and thirty-three (12%) fungi extracts exhibited antibacterial properties against some of the selected bacteria. E. coli was found to be the most susceptible in contrast to E. faecium and E. gallinarum which were the most resistant. The isolate MHE 68, identified as Alternaria sp. displayed the greater spectrum of antibacterial activities by controlling selected clinical bacteria strains including resistant E. faecium and E. gallinarum. The chemical analysis of the extract from MHE 68 indicated that linoleic acid (9,12-octadecadienoic acid (Z,Z)) and cyclodecasiloxane could be accountable for the antibacterial activity. This is the first study conducted on the secondary metabolites produced by endophytic fungal strains isolated from the Pelargonium sidoides DC. possessing antibacterial properties.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.180-184
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• 2006

Nineteen nitrogen-fixing bacteria were isolated from rice roots cultivated in the southern part of the Korean peninsula. Among them, three isolates - Stenotrophomonas sp. KNUC89, Pseudomonas sp. KNUC116, and Delftia sp. KNUC133 - showed antifungal activities against phytopathogenic fungi Rhizoctonia solani and Fusarium oxysporum. Besides they could produce auxin and siderophores.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.96-99
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• 2006

In this study, we have attempted to determine the optimum concentration of inducers responsible for efficient laccase production by the white-rot fungus, Trametes sp. Variations in laccase activity were investigated with changing concentrations of 2,5-xylidine, syringaldazine, ABTS, and guaiacol. Enhancement of peak laccase activity was achieved via the combination of 2,5-xylidine with ABTS, syringaldazine, or guaiacol, resulting in increases of up to 359, 313, and 340%, respectively, as compared to control values. Among the tested inducers, the addition of 0.1mM of ABTS coupled with 1.0mM of 2,5-xylidine in the medium after 24 h of cultivation proved optimal with regard to laccase enzyme production.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.873-876
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• 1999

Aspergillus sp. CX-l strain grown on microcrystalline cellulose resulted in the accumulation of high levels of cellulase and xylanase activities that were higher by two to four folds than those from the conventional commercial producer, Trichoderma reesei QM9414. Aspergillus sp. CX-1 demonstrated greater thermo stability and better catalytic characteristics of total cellulase activity (FPase) as compared to T. reesei and Aspergillus niger F-2039.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.4
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• pp.123-128
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• 2020

All plants in natural ecosystems are living in symbiosis with endophytes. Recently, there has been an increasing interest in endophytes since these organisms can interact with the hosts and produce various structurally or biologically interesting molecules. This study aimed to identify these molecules from endophytes. Chemical investigation of Climacium dendroides-derived fungus Talaromyces sp. resulted in the isolation of two diphenyl ether derivatives, purpactin A (1) and penicillide (2), and two steroids, dankasterone A (3) and calvasterol B (4). The structures of the compounds were identified via extensive spectroscopic and spectrometric methods. Four compounds did not show any antioxidative activities in the on-line antioxidant activity screening system.

• Mycobiology
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• v.49 no.1
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• pp.46-53
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• 2021

In a study of the fungal diversity on Ulleung Island in Korea, three novel strains of Penicillium were isolated. Different sites on Ulleung Island were selected for collecting endophytic fungi, and three endophytic fungal strains showed unique morphological characteristics. DNA sequence of the internal transcribed spacer, β-tubulin, calmodulin, and RNA polymerase II second largest subunit regions of the strains were analyzed and they showed unique taxonomic position from the other species of Penicillium section Sclerotiora. The new strains were named Penicillium ulleungdoense sp. nov. As the novel endophytic Penicillium taxa were discovered in a unique environment, the data could be meaningful for understanding the geographical distribution of Ascomycetes on Ulleung Island.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.1-8
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• 2008

To investigate the mycoflora of indoor air in a Sogokju, traditional rice wine, factory, fungi were sampled and analyzed from the air of several rooms in the factory using an Anderson air sampler and from two kinds of Nuruk. Twelve fungal species belonging to the genera of Aspergillus, Penicillium, Gibberella, Cladosporium, and Talaromyces were isolated. Species belonging to Aspergillus and Penicillium genera were the major species. Seven different species of Penicillium were isolated from each different room of the factory. The Aspergillus species found from indoor air of the factory was also found from Nuruk. Rhizopus sp. was commonly isolated from Nuruk but not from indoor air of the factory. This is first report of fungi present in indoor air of a traditional rice wine factory in Korea.

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.183-190
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• 1981

Alternaria sesami, A. sesamicola, A. tenuis, A. longissima, Cercospora sesami, Cephalosporium sp., Corynespora cassiicola, Fusarium equiseti, F. moniliforme, F. oxysporum, F. semitectum, Macrophomina phaseolina and Myrothecium roridum were detected from 40 seed samples of sesame. A sesami, A. sesamicola, A. tenuis and C. cassiicola were the predominant fungi. Except C. cassiicola, all fungi were almost completly reduced and wiped out the infection by pretreatment with chlorine. Plating components also indicate that C. cassiicola was well-established infections. Seedborne infection of C. cussiicola caused heavy seed rot and seedling mortality. Detailed description has been given on the habit character of C. cassiicola under stereoscopic microscope and the variation in colony character and spore morphology have been taken into account. In inoculation experiments, C. cassiicola produced severe leaf and stem spots and blights on sesame plants resulted in ultimate death of the plants. A. sesami, A. sesamicola A. longissima and C. sesami also produced mild to severe leaf spotting and leaf blight when suspension of their conidia were sprayed on to plants. In soil inoculation experiments, F. oxysporum and M. phaseolina were the most pathogenic causing seed rot and seedling blight.

• Korean journal of applied entomology
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• v.27 no.1
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• pp.41-46
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• 1988

Growth of Metarrhizium flavoviride var. minus and Hirsut lle strigosa showed good yield in the carbon source media adding dextrose, starch and saccharose, but Hirsutella sp. from korea greq well in the other media except in the dextrose media. Yeast extract was necessary for the mecelial growth of the fungi, but the fungi tested in this experiment showed a difference in the amount of required yeast extract. Growth of Nomurea rileyi was fastidious in the carbon and nitrorgen sourced media and the optimum pH of the media for growth was at 6.7. Sporulation of M. Flavoviride var. minus was high on media, containing 1%~2% of yeast extract as nitrogen and carbon source media, but N. rileyi sporulated abundantly on the media with nitrogen and dextrose.

• Advances in nano research
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• v.3 no.2
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• pp.97-109
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• 2015

Citrate ion is a commonly used reductant in metal colloid synthesis, undergoes strong surface interaction with silver nanocrystallites. The slow crystal growth observed as a result of the interaction between the silver surface and the citrate ion makes this reduction process unique compared to other chemical and radiolytic synthetic methods. The antimicrobial effects of silver (Ag) ion or salts are well known, but the effects of citrate coated Ag nanoparticles (CAgNPs) are scant. Herein, we have isolated biofilm causative bacteria and fungi from drinking water PVC pipe lines. Stable CAgNPs were prepared and the formation of CAgNPs was confirmed by UV-visible spectroscopic analysis and recorded the localized surface plasmon resonance of CAgNPs at 430 nm. Fourier transform infrared spectroscopic analysis revealed C=O and O-H bending vibrations due to organic capping of silver responsible for the reduction and stabilization of the CAgNPs. X-ray diffraction micrograph indicated the face centered cubic structure of the formed CAgNPs, and morphological studies including size (average size 50 nm) were carried out using transmission electron microscopy. The hydrodynamic diameter (60.7 nm) and zeta potential (-27.6 mV) were measured using the dynamic light scattering technique. The antimicrobial activity of CAgNPs was evaluated (in vitro) against the isolated fungi, Gram-negative and Gram-positive bacteria using disc diffusion method and results revealed that CAgNPs with 170ppm concentration are having significant antimicrobial effects against an array of microbes tested.