• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.214-221
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• 2014

The deterioration in wood by the brown-rot fungus (Fomitopsispalustris) and the white-rot fungus (Trametesversicolor) were measured using ultrasonic velocity. Those were used for the decay exposure and 4 wood species of wood as the test specimens, Pinusdensiflora, Larixkaempferi, Pinuskoraiensis and Pinusrigida, were chosen with both the brown- and white-rot culture petridish during 12 weeks. After 12 weeks, the decrease rate of ultrasonic velocity was measured at 10~15%. In both brown- and white-rot exposure experiments, P. rigida showed significant decrease in ultrasonic velocity (20%), L. kaempferi on the other hand did not show decrease in ultrasonic velocity. After the fungal exposure experiment, the inside of specimens was investigated by computer tomography (C/T). After C/T investigation, bending tests were performed.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1455-1463
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• 2014

In the past, reactive oxygen species (ROS) have been considered a harmful byproduct of aerobic metabolism. However, accumulating evidence implicates redox homeostasis, which maintains appropriate ROS levels, in cell proliferation and differentiation in plants and animals. Similarly, ROS generation and signaling are instrumental in fungal development and host-fungus interaction. In fungi, NADPH oxidase, a homolog of human $gp91^{phox}$, generates superoxide and is the main source of ROS. The mechanism of activation and signaling by NADPH oxidases in fungi appears to be largely comparable to those in plants and animals. Recent studies have shown that the fungal NADPH oxidase homologs NoxA (Nox1), NoxB (Nox2), and NoxC (Nox3) have distinct functions. In particular, these studies have consistently demonstrated the impact of NoxA on the development of fungal multicellular structures. Both NoxA and NoxB (but not NoxC) are involved in host-fungus interactions, with the function of NoxA being more critical than that of NoxB.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.11a
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• pp.11-16
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• 2001

If microorganisms are injected into porous medium such as soils along with appropriate substrate and nutrients, soil pore size and shape are changed from the initial condition as a result of biofilm formation, which make hydraulic conductivity reduced. In this research, hydraulic conductivity reduction was measured after specific bacterium or fungus was inoculated into soil pore. Hydraulic conductivity was decreased to 10 % ∼ 1 % and maintained constant while substrate was provided. Under the adverse conditions such as no substrate, chemical solution permeation, and freeze-thaw cycles, hydraulic conductivity was increased 30∼50%. Hydraulic conductivity decrease of fungus-soil mixture was faster than that of bacterium-soil mixture. Fungus-soil mixture, however, was more sensitive to the adverse conditions.

• Imaging Science in Dentistry
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• v.40 no.2
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• pp.93-97
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• 2010

This report was to show the radiographic appearances of the fungus ball in a paranasal sinus and to emphasize the scan area of cone beam computed tomography (CBCT) to detect the calcification in the paranasal sinus. A seventyfour-year-old woman visited our department for the implant rehabilitation at both maxillary posterior edentulous region. Pre-operative radiographic examinations including the panoramic, CBCT, and multidector CT images were taken. An opacification in the right maxillary sinus was observed on the multiplanar image of CBCT, however the pre-determined scan area of CBCT in this report hardly showed the calcifications at the central portion of the maxillary sinus. The opacification in the maxillary sinus could be misdiagnosed as chronic maxillary sinusitis if the calcification of fungus ball was not simultaneously detected. The scan area of pre-operative CBCT needs to be enough to scan the paranasal sinus from top to bottom.

• Preventive Nutrition and Food Science
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• v.7 no.1
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• pp.37-42
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• 2002

Factors affecting the production of bacterial cellulose and organic acids in Kombucha fermentation were investigated. Kombucha was obtained by the fermentation (for 12 days at 3$0^{\circ}C$) of the green/black tea extract, supplemented with 10% white sugar, using an Oriental tea fungus as starter. Hitgher initial pH increased acid production with decreased cellulose production. With a cellulose pellicle or tea fungus broth as a starter, a 1~3 mm thick cellulose layer developed as a top layer every four days, and was removed subsequently while continuing fermentation. Addition of 30 mL tea fungus broth (13%, v/v) in Kombucha fermentation resulted in maximum production of a cellulose pellicle, indicating weak acid production. Yield of cellulose production at an early stage of fermentation was also higher when Kombucha was inoculated with a cellulose pellicle. In fact, addition of 1% (v/v) alcoholic beverage in the Kombucha fermentation activated the cellulose production, coupled with four times higher acid production.

• Mycobiology
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• v.43 no.3
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• pp.210-217
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• 2015

A seed-borne fungus, Curvularia sp. EML-KWD01, was isolated from an indigenous wheat seed by standard blotter method. This fungus was characterized based on the morphological characteristics and molecular phylogenetic analysis. Phylogenetic status of the fungus was determined using sequences of three loci: rDNA internal transcribed spacer, large ribosomal subunit, and glyceraldehyde 3-phosphate dehydrogenase gene. Multi loci sequencing analysis revealed that this fungus was Curvularia spicifera within Curvularia group 2 of family Pleosporaceae.

• Journal of the Korean Wood Science and Technology
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• v.32 no.3
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• pp.79-87
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• 2004

The objectives of this study were to select superior fungus for lignin degradation and to decolor dyes by selected fungus. Ligninolytic fungi were screened and isolated from decayed woods. Ten ligninolytic fungi were selected by ligninolytic enzyme activity on the PDA media containing rhemazol brilliant blue R, guaiacol and gallic acid. Their lignin degradation abilities were tested on the extractive-free wood powder of Quercus acutissima and Pinus densiflora. As a result, 8J-28 was selected as superior fungus for lignin degradation. Also, decolorization abilities of dyes were examined by shaking and static culture. And congo red, crystal violet, poly R-478, methylene blue used to investigate decolorization abilities of dyes. As a result, 8J-28 showed over 90% in decolorization of congo red, crystal violet, poly R-478.

• Mycobiology
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• v.50 no.2
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• pp.150-154
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• 2022

Rhytisma lonicericola was identified as a tar spot fungus on Lonicera sp. in 1902, and has since been recorded on several species of Lonicera in China, Japan, and Korea. Most of the previous records of R. lonicericola have been based on a list of disease occurrences in the absence of any formal morphological identification or molecular analyses. Using six newly obtained specimens collected in the past 2 years, we confirmed the tar spot fungus found on L. japonica in Korea as R. lonicericola based on morphological examinations and molecular phylogenetic analyses. This fungus was distinguished from R. xylostei, another tar spot fungus on Lonicera, by ascospore size and geographical distributions. We present detailed mycological information and, for the first time, DNA sequence data useful for the identification of R. lonicericola.

• Journal of Forest and Environmental Science
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• v.34 no.5
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• pp.395-404
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• 2018

Since the mass mortality of Quercus mongolica has been first reported in Gyeonggi province at 2004, the disease spread rapidly over Korean peninsula annually. Ambrosia beetle (Platypus koryoensis) was known as the insect vector of oak wilt fungus, Raffaelea quercus-mongolicae, and control methods of the disease had mainly been focused on eradication of insect vector. However, for the efficient management of the disease, combined control methods for both of the pathogenic fungus and insect vector are strongly required. As one of the efforts to suppress the pathogenic fungus, antifungal activities of Streptomyces isolated from oak forest soil were assayed in this study. Optimum culture condition for the selected isolates was also studied, As a result, Streptomyces blastmyceticus cultured in PDB (Potato Dextrose Broth) at $25^{\circ}C$ for 1 week showed the strongest antifungal activity against oak wilt fungus. Mycelial growth inhibition rates (MGIRs) of Streptomyces isolates were compared on culture media supplemented with heated and unheated culture filtrates of S. blastmyceticus. MGIRs on culture media with unheated culture filtrates were generally higher than those on culture media with heated culture filtrates. Antagonistic mechanism to get involved in the inhibition of hyphal growth and spore formation of the pathogen is due to the antifungal metabolites produced by Streptomyces. This study will provide the fundamental information in developing biocontrol agents for the environment-friendly management of oak wilt disease.

• Journal of the Korean Wood Science and Technology
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• v.34 no.1
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• pp.61-67
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• 2006

The purpose of this study was to develop soil conditioner using wood decay fungus. The effect of soil conditioner treated with SJ-28 fungus was tested by lettuce cultivation. Cultivating efficiency was investigated by the yield of lettuce. In the plot of soil conditioner treated with SJ-28 fungus (FPG) showed weight of lettuce leaves 4425 g of total yield which was greater than 2434 g shown in the control. Also the numbers of actinomyces and fungi were increased in the plot of soil conditioner treated with SJ-28 fungus (FPG), beneficial for soil. The number of bacteria showed decrease in FPG plot. FPG showed possibility as a soil conditioner.