• Journal of Environmental Health Sciences
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• v.35 no.2
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• pp.95-99
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• 2009

This study was performed to investigate the possible effect of garlic produced in Korea on the inhibition/reduction of growth of A. parasiticus, a toxigenic strain. The effect was studied using different concentrations of freeze-dried garlic in potato-dextrose agar (PDA) and/or in yeast-extract sucrose (YES) broth at $25^{\circ}C$ for 15 days. While inhibition of the fungal growth due to increasing the concentration of garlic was observed, the more remarkable effect was observed on the ninth day. Reduction of fungal diameter as a result of addition of garlic on PDA was observed to range between 3.4% to 20.1 % while reduction of mycelial weight in YES broth ranged from 9.9% to 30.5%. The 0.5% and 1.0% concentrations of garlic significantly reduced fungal diameter in PDA on the 9th day, while 0.1 %, 0.5%, and 1.0% concentrations of garlic significantly reduced the mycelial weight in YES broth (p<0.05). Dose-response relationships were observed between the concentration of garlic and inhibition of growth both in solid culture and in liquid culture. This study indicates that garlic could be an effective inhibitor at a human consumption level of the growth of A. parasiticus. More research is needed to study the inhibitory effects of the main active component of garlic.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.106-113
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• 1994

A novel method for production of concentrated purity maltose using swollen extruded corn starch was investigated. Degree of gelatinization of extruded starch suitable for maltose formation was found to be around 70%. The optimal amiunt of enzyme was 400 unit fungal $\alpha $-amylase per g of starch, and the reaction time was 12 hours. At extruded starch concentration of 300 g/l(w/v), maltose concentration and content were reached up to 220 g/l(w/v) and 77%(w/w), respectively. The maltose forming reaction was also successfully proceeded at high starch concentration of 700 g/l(w/v), however, the conversion yield and content were decreased. By the addition of extruded starch by fed-batch wise, the maltose concentration, purity, and conversion yield could be improved up to 465 g/l(w/v), 70%(w/w), and 0.63, respectively. The investigated maltose production process seems to have many potential advantages over the conventional process utilizing liquefied starch, and the feasibility for industrial application needs to be evaluated.

• Journal of Microbiology
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• v.42 no.2
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• pp.94-98
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• 2004

Phenanthrene is a three-ring polycyclic aromatic hydrocarbon and commonly found as a pollutant in various environments. Degradation of phenanthrene by white rot fungus Trametes versicolor 951022 and its laccase, isolated in Korea, was investigated. After 36 h of incubation, about 46％ and 65％ of 100 mg/l of phenanthrene added in shaken and static fungal cultures were removed, respectively. Phenanthrene degradation was maximal at pH 6 and the optimal temperature for phenanthrene removal was 30$^{\circ}C$. Although the removal percentage of phenanthrene was highest (76.7％) at 10 mg/1 of phenanthrene concentration, the transformation rate was maximal (0.82 mg/h) at 100 mg/L of phenanthrene concentration in the fungal culture. When the purified laccase of T. versicolor 951022 reacted with phenanthrene, phenanthrene was not transformed. The addition of redox mediator, 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) or 1-hydroxybenzotriazole (HBT) to the reac-tion mixture increased oxidation of phenanthrene by laccase about 40％ and 30％, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.485-491
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• 2015

This study was performed to investigate thermophilic bacteria from soil having broad antifungal spectrum against Rhizoctonia solani, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f.sp. lycopersici, and Botrytis cinerea. One isolate selected could resist heat shock of $60^{\circ}C$ for one hour, and had broad antifungal activity in dual culture assay against all tested fungal pathogens and was identified as Bacillus amyloliquefaciens Y1 using 16S rRNA gene sequence. Further investigation for antifungal activity of bacterial culture filtrate (BCF) and butanol crude extract (BCE) of various concentrations showed broad spectrum antifungal activity and fungal growth inhibition significantly increased with increasing concentration with highest growth inhibition of 100% against R. solani with 50% BCF and 11 mm of zone of inhibition against R. solani with 4 mg BCE concentration. Treatment of butanol crude extract resulted in deformation, lysis or degradation of C. gloeosporioides and P. capsici hyphae. Furthermore, B. amyloliquefaciens Y1 produced volatile compounds inhibiting growth of R. solani (70%), C. gloeosporioides (65%) and P. capsici (65-70%) when tested in volatile assay. The results from the study suggest that B. amyloliquefaciens Y1 could be a biocontrol candidate to control fungal diseases in crops.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.497-499
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• 2005

Bioconverted hydroxy fatty acid, docosahexaenoic (bDHA) obtained from the microbial conversion by Pseudomonas aeruginosa PR3 was evaluated for its in vivo anti-fungal activity. bDHA showed great potential of anti-fungal activity against phytopathogenic fungi tested in this study. bDHA at the concentration of 500 ${\mu}g/ml.$ showed remarkable anti-fungal activity against all the fungus tested.

• YAKHAK HOEJI
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• v.43 no.4
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• pp.502-508
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• 1999

Chitin is an important structural component of fungal cell wall and is synthesized by chitin synthase I, II, and III. The chitin synthase II is an essential enzyme for the formation of primary septum in Saccharomyces cerevisiae. Therefore, specific inhibitors of this enzyme might block the formation of fungal cell wall and could be used as effective antifungal agents. To search chitin synthase IIinhibitors from natural products, 67 plants were extracted with methanol and examined for the inhibitory activities against chitin synthase II of S. cerevisiae by our cell free assay system. As a result, the extracts from 16 plants showed more than 70% inhibition at the concentration of $280{\;}\mu\textrm{g}/ml$. Of note, Laurus nobilis (81.4%), Lonicera maackii (81.5%), Berchemia berchemiaefolia (82.9%), Koelreuteria paniculata (87.9%), Chamaecyparis pisifera (86%) and Taxus cuspidata (83.9%) inhibited strogly the chitin synthase IIactivity.

• Mycobiology
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• v.35 no.3
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• pp.124-128
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• 2007

Ganoderma resinaceum tolerated sodium chloride salt stress within a range of 0 mM till 300 mM. It responded to salt stress with fluctuation in proline formation at different NaCl concentrations. However, the mycelial dry weight, total protein contents and exopolysaccharides did not changed considerably. Increasing sodium chloride concentration led to morphological alteration in fungal mycelia with disappearance of fungal cell wall, plasmolysis, and vacuolation as indicated with electron microscopic examination of the fungal growth.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.4
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• pp.256-262
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• 2010

This study evaluated the airborne concentrations of fungi in university laboratories, hospital diagnostic laboratories in Seoul. The incubated fungi was identified by lactophenol cotton blue (LPCB) staining method. Variables such as types of ventilation, temperature and relative humidity were investigated to explain laboratory airborne fungal concentrations. A total of 97 air samples were collected from 10 facilities in two institutions. Aspergilus spp., including Aspergilus niger, Aspergillius flavos and Penicillium spp. were found as predominant species. Airborne fungal concentrations ranged from not detected (ND) to 1,890 CFU/$m^3$. Airborne fungal concentrations were high in general-ventilated facilities and in laboratories where relative humidity ( > 60 %) were high ( p < 0.001). Therefore, we suggest that relative humidity should be maintained to properly reduce the concentration of fungal in university and hospital laboratories.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1206-1211
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• 2013

The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory fungal metabolites, the organic extracts of several fungal species isolated from marine environments were found to exhibit significant inhibitory effects, and the bioassay-guided investigation of these extracts resulted in the isolation of fructigenine A (1), cyclopenol (2), echinulin (3), flavoglaucin (4), and viridicatol (5). The structures of these compounds were determined mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 10.7, 30.0, 29.4, 13.4, and 64.0 ${\mu}M$, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compounds 1 and 5 suggested that compound 1 inhibited PTP1B activity in a noncompetitive manner, whereas compound 5 inhibited PTP1B activity in a competitive manner.

• KSBB Journal
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• v.21 no.5
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• pp.331-335
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• 2006

Suspension cells of Angelica gigas Nakai were cultivated to produce extracellular polysaccharide(ECP) as immunostimulating agents. Effects of environmental conditions such as sucrose and 2,4-dichlorophenoxyacetic acid(2,4-D) concentrations on the growth and production of ECP were studied using suspension cultures of A. gigas Nakai. Final dry cell weight was increased with an increase of initial sucrose concentration from 30 to 60 g/L. The maximum production of ECP(1.2 g/L) was achieved at an initial sucrose concentration of 50 g/L on day 8. High 2,4-D concentration was effective for ECP production but not for cell growth. In addition, various fungal elicitors were investigated for the enhanced production of ECP in A. gigas suspension cultures. Among the tested fungal elicitors, Verticillium dahliae was the most effective for the production of ECP in A. gigas suspension culture.