• YAKHAK HOEJI
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• v.45 no.6
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• pp.588-590
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• 2001

Two flavanones, (2S) -2'-methoxykurarinones (1) and kurarinones (2) , were isolated from the ethyl acetate extract of the roots of Sophora flavescense Ait. Their structrures were elucidated using NMR, UV and IR spectral analysis. These compounds exhibited a moderate antimicrobial activities against Staphylococcus aureus, Staphylococcus epidermidis Pseudomonas Putida and a weak anti-fungal activity against Candida albicans.

• The Korean Journal of Mycology
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• v.13 no.4
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• pp.227-233
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• 1985

Studies on the varietal resistance and effects of nutrients for fungal growth were carried out in order to obtain basic materials for breeding resistant variety and control measures of the red pepper anthracnose disease caused by Colletotrichum dematium f. sp. capsicum. Four cultivars such as Kumchang No. 2, Bulamhouse, Pakistan, Hongilpum were resistant among twenty-one pepper cultivars, and five cultivars including Taiwan pepper were moderate. The remaining twelve cultivars including H-038 and Saegochu were susceptible. These susceptible cultivars were mostly belonged to sweet taste cultivars. Glucose was known the best source for fungal growth, and near 3 percent of carbon concentration was the best for mycelial growth of the fungus. Conidial sporulation was rather decreased by adding high concentrations of C-source, whereas fungal dry weight was a positive tendency in proportion to increasing carbon concentrations. N-sources and vitamins were not remarkable as that for carbon, and rather a decreasing trend for mycelial growth by adding N-source. Especially, the lowest of mycelial growth was in the case of Czapek-Dox plus ammonium sulfate. The medium plus vitamins either niacin or thiamine was slightly increased to mycelial growth.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.82-89
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• 2004

Two kinds of chemicals (RNF-3 and RNF-4) with high anti-mold effectiveness against stored fungi causing fungal discoloration was selected from among the six kinds of fluoride-based chemicals in the preceding study. In this study, the anti-mold test using 16 species fungi isolated from the softwood lumbers which were fungal discolored and field test in the sawmill was carried out to prove the feasibility for practical using of selected chemicals.For the isolated fungi, the RNF-3 consist of F and Cu showed high mycelial growth control in the PDA medium and fungicidal effectiveness in the japanese red pine (Pinus densiflora), korean pine (Pinus koraiensis) and radiata pine (Pinus radiata) when the concentration was 2% or more. However the RNF-4 consist of F only was not effective compared with RNF-3 because of mycelial growth in the PDA medium and wood treated with 2% or more chemical solution. The RNF-3 also showed a strong anti-mold effectiveness because there was no fungal discoloration for the radiata pine boards treated by 2% and 10 min. soaking in the field test. These results mean that RNF-3 can be used as domestic anti-stain chemicals for prevention of fungal discoloration of the softwood lumber

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.306-311
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• 1998

Effects of soluble silicon and surfactants on the development of powdery mildew of cucumber were tested for environmentally safe powdery mildew control. Tested soluble silicon was potassium silicate$(K_2SiO_3)$ and tested commercial surfactants were Jeonchakje, Silhouette, Kaba, and Tween 20. Tested concentrations were 2, 4, 8, 16mM for the soluble silicon, 0.5 and 1.0% for Tween 20, 0.05 and 0.1% for both Jeonchakje and Kaba, and 0.03 and 0.07% for Silhouette. Water dilutions of tested materials were sprayed on cucumber (Cucumis sativus) leaves once a week for 4 weeks. From 3 days after the second spray, the diseased area and the numbers of fungal colony were measured from the treated leaves for 6 times at 3-4 days interval. Powdery mildew was less severe on treated cucumber compared to distilled water-treated cucumber (check). In all treatments, diseased area index was proportional to the number of the fungal colony. At the end of investigation, there was severe powdery mildew on check cucumbers. Average 30% of a leaf was colonized by powdery mildew fungus and the average number of the fungal colony per leaf reached to more than 70. On the other hand, none of the treated cucumber suffered severe powdery mildew. The treatments including 8 and 16mM of soluble silicon, doubled concentration of Kaba, and 0.5 and 1.0% of Tween 20 showed more than 80% of control effect compared to water-treated cucumber. In addition, no phytotoxicity was found. Potassium silicate and Tween 20 showed the possibility to replace chemical pesticides for the control of powdery mildew.

• Korean Journal of Environmental Biology
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• v.19 no.2
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• pp.153-157
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• 2001

The relationship between SPM (Suspended Particulate Matter) and fungal spore in the air was investigated in Seosan, a rural county of Korea, in spring of 2000. SPM concentrations in the air were $199.8\mu{g}\;m^{-3}$, in the 1st Yellow Sand Period (March, 23-24), $249.4\mu{g}\;m^{-3}$ in the 2nd Yellow Sand Period (April, 7-9) and $98.9\mu{g}\;m^{-3}$ in the Non Yellow Sand Period (May, 12-16), respectively. Although there was somewhat difference in total SPM concentration between the two Yellow Sand Periods, majority of the total SPM were composed of $5\mu{m}$ sized coarse particles over the two periods. However, fine particles sized about $1\mu{m}$and coarse particles sized about $5-6\mu{m}$ ultimately showed peaks, which was within typical bimodal pattern at the graph of SPM size distribution in the Non Yellow Sand Period. Four mold genera grown from airborne fungal spores were finally identified in full-grown colonies at the SPM samples during the Yellow Sand Periods. These genera were Fusarium, Aspergillus, Penicillium and Basipetospora.

• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.72-78
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• 2003

In the process of producing chitosan from crustacean shell, the use of excessive acid and alkli is causing the problems of environmental pollution and of production cost. In this study, one way to solve these problems is to cultivate fungi, then, to extract chitosan from the cell wall. By means of flask incubation and batch cultivation, the optimum cultivation conditions for mass production of continuous cultivation was found. Four strains used for the production of fungal chitosan were Gongronella butleri IF08080, Absidia coerulea IF05301, Rhizopus delemar IF04775, Mucor tuberculisporus IF09256. In flask incubation to select strain of producing much chitosan by means of experiment of the effect of initial pH, Absidia coerulea IFO 5301 had highest yield in FCs, 258.1 $\pm$ 47.3 mg/200 $m\ell$l at pH 6.5. In flask incubation under the optimum cultivation condition, temperature 27$^{\circ}C$, culture time 6days, glucose 2%, peptone 1%, (NH$_4$)$_2$ SO$_4$ 0.5%, $K_2$HPO$_4$ 0.1 %, Nacl 0.1 %, MgSO$_4$ㆍ7$H_2O$ 0.05%, CaCl$_2$ㆍ2$H_2O$ 0.01 %, the yield of DCW brought the highest yields. In batch bioreactor, the optimum cultivation condition was that cell suspended solution was 70 $m\ell$, aeration rate 0.5 l/min, agitation rate 800 rpm, culture time 36 hr. In continuous bioreactor, the optimum substrate flow rate was 4 ι/day.

• Microbiology and Biotechnology Letters
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• v.19 no.3
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• pp.290-295
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• 1991

Direct conversion of raw starch without liquefaction to maltose using maltose-forming fungal a-amylase (Fungamyl) was carried out in an agitated bead enzyme reactor (bioattritor). The reaction rate in bioattritor was comparable with conventional method which utilized liquefied soluble starch. Moreover the extent of maltose formation increased substantially compared with conventional method; from 150 g / I of raw starch, around 95 g/l of maltose was formed and 72% of maltose content in sugar mixture was achieved. Especially, pH influenced greatly not only on total sugar formation from raw starch in bioattritor but also on maltose content in sugar mixture. The optimal pH for maltose formation from raw starch was shifted into the weak alkaline pH, the optimal pH of 8.0~9.0 in bioattritor contrast to pH of 5.0~5.5 for liquefied starch. The maltose formation and content were also affected by the amounts of Fungamyl added and raw starch concentration. Consumption of maltose-forming Fungamyl can be substantially reduced by supplementary addition of starch liquefying a-amylase (Termamyl).

• Food Science and Preservation
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• v.10 no.4
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• pp.498-505
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• 2003

This was studied to evaluate the rheology properties of the Dumpling shell added chitosans(commercial and prepared from fungal), polyphosphate, guargum and tapioca. The physicochemical properties of fungal chitosans (FCs95 and FCs 40) were as follows respectively. The nitrogen was 6.71% and 6.9％, the solubility 99.05% and 99.13％, the viscosity 2.23cps and 2.21cps, the acetylation 12.0% and 12.7% and the molecular weight 3.12${\times}$10$\^$5/Dalton and 3.01${\times}$10$\^$5/Dalton. From the above facts, the components and physicochemical properties of two kinds of fungal chitosan had little difference. The addition of polyphosphate, guargum and tapioca showed effect on the texture parameters(hardness, cohesiveness, springiness and gumminess) of Dumpling shell dough and the optimum addition concentration wag 0.074%, 6.59% and 0.062%(w/w), respectively. In case of chiotsans addition, texture of the dough by added SCs, FCs95 and FCs40 showed effect.

• Proceedings of the Korea Contents Association Conference
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• 2018.05a
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• pp.409-410
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• 2018

Background: Asthma is one of the most common chronic diseases and can be affected by environmental factors. It has been reported that exposure to indoor environmental factors can cause infantile asthma during infancy and childhood, but the previous studies are not yet clear. Climate change has recently been shown to increase indoor mold. Exposure to fungi is known to be directly related to the development of aggravation. Methods: This study was conducted from July 20, 2016 to September 30, 2016. The study was conducted on 90 household with children under the age of 7 who attend atopy school. The questionnaire surveyed allergic symptoms, social and demographic characteristics, and environmental characteristics. Environmentally hazardous substances were measured such as temperature, humidity, fine dust, volatile organic compounds, formaldehyde, bacteria, fungus, house dust mite, endotoxin. Results: According to the survey results, 9 patients (10%) were treated with asthma, 6 (6.7%) were asthmatic patients during the past 12 months, and 4 patients (4.4%) were asthmatic patients during the past 12 months. There were statistically significant differences in the direct effect of smokers in the family (P=0.0328). High-filter vacuum cleaners collected $0.4222CFU/m^3$ in subjects without asthma, and $0.2222CFU/m^3$ in subjects with asthma. In addition, various results confirmed that asthma exacerbated by mold exposure. Conclusions: The results of this study suggest that exposure to fungal by infants and toddlers may play an important role in the development of asthma. In this study, we investigated the relationship between asthma and fungal concentration.

• The Plant Pathology Journal
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• v.39 no.4
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• pp.351-360
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• 2023

Citrus melanose, caused by Diaporthe citri, has been one of the serious diseases, and chemical fungicides were used for protection in many citrus orchards of Jeju Island. Establishing a disinfectant resistance management system and reducing pesticide usage would be important for contributing to safe agricultural production. In this study, monitoring of chemical resistance was performed with 40 representative D. citri isolates from many citrus orchards in Jeju Island. Four different fungicides, kresoxim-methyl, benomyl, fluazinam, and prochloraz manganese, with seven different concentrations were tested in vitro by growing the mycelium of the fungal isolates on the artificial medium potato dextrose agar. Among the 40 fungal isolates, 12 isolates were investigated as resistant to kresoxim-methyl which could not inhibit the mycelium growth to more than 50%. Especially isolate NEL21-2 was also resistant against benomyl, whose hyphae grew well even on the highest chemical concentration. However, any chemical resistance of fungal isolates was found against neither fluazinam nor prochloraz manganese. On the other hand, in vivo bio-testing of some resistant isolates was performed against both kresoxim-methyl and benomyl on young citrus leaves. Typical melanose symptoms developed on the citrus leaves pre-treated with both agrochemicals after inoculation with the resistant isolates. However, no or less symptoms were observed when the susceptible isolates were inoculated. Based on these results, it was suggested that some resistant isolates of D. citri occurred against both systemic fungicides, which may be valuable to build a strategy for protecting citrus disease.