• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.634-637
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• 2012

In strawberry production, among others, the high incidence of diseases by pathogenic fungi resulting in the reduction of fruit yield and quality requires the development of eco-friendly management systems rather than chemical sprays to control them. The diameter of colonies grown in media at $25^{\circ}C$ for 5 days was measured to evaluate the in vitro inhibition of mycelial growth of 5 pathogenic fungi by irradiation with ultraviolet (UV-C, 264 nm). The mycelial growth of 5 pathogenic fungi was inhibited in potato dextrose agar (PDA) by the irradiation of UV-C for 1 hour a day, and was dramatically inhibited by the irradiation of UV-C for 9-12 h a day. The irradiation of UV-C for 9-12 h a day inhibited completely the growth of the late blight pathogen, Phytophthora cactorum. The irradiation distance of 40 to 50 cm was effective for the inhibition of mycelial growth of fungi. The mycelial growth of fungi without pre-incubation was inhibited strongly by UV-C irradiation compared to fungi pre-incubated for 2 days without light. The mycelia growth of Colletotrichum gloeosprioides and Fusarium oxysporum was inhibited strongly by UV-C irradiation in vegetable 8 juice agar compared to PDA.

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.89-95
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• 1986

The five short-chain fatty acids such as isobutyric(C-4), butyric(C-4), isovaleric(C-5), valeric(C-5) and caproic (C-6) acids obtained from the extract of common purslane showed wide antifungal spectra against spore germination and mycelial growth of the twenty five phytopathogenic fungi tested in vitro, although there were differences in antifungal potency among them. The antifungal potency of each fatty acid varied significantly against different fungi in spore germination and mycelial growth. The seventeen fungi used for spore germination test and the sixteen fungi used for mycelial growth test can be divided into three groups depending upon differences in minimal inhibitory concentration of each fatty acid for them, respectively. Caproic acid was significantly more toxic to germination than to mycelial growth of the test fungi, while the other four fatty acids did not show such a significant differences in toxicity with a few of exceptions as shown in valerie acid. The longer the chain-length of fatty acid was, the higher the antifungal potency was shown. The normal fatty acids such as butyric and valerie acid were more toxic than their isomers to spore germination and mycelial growth of the test fungi. Each fatty acid was more toxic to spore germination of obligate parasites and some of facultative parasites, and mycelial growth of facultative parasites than to spore germination and mycelial growth of saprophytes, respectively.

• The Korean Journal of Mycology
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• v.45 no.4
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• pp.319-327
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• 2017

In this study, we investigated the culture conditions of four ectomycorrhizal fungi, namely, Amanita spissacea NIFoS 2719, Pisolithus arhizus NIFoS 2784, Suillus spraguei NIFoS 2848, and Xanthoconium affine NIFoS 2716, in solid and liquid culture media. In addition, we attempted to induce in vitro mycorrhization of the fungi with Pinus densiflora. Prior to liquid culture, we determined the optimal culture conditions for each species in solid media. The results revealed that all species examined are capable of growth in potato dextrose agar (PDA), malt extract agar (MEA), and modified Melin-Norkran's medium (MMN), although their preferred growth media were different. Liquid culture experiments showed that inorganic nitrogen did not enhance the mycelial growth of all four species. Therefore, we used MMN-based liquid inocula to promote the growth of ectomycorrhizal fungi in our symbiosis culture system. Mycorrhization was observed in Xanthoconium affine NIFoS 2716. Morphological analysis revealed that fungi-inoculated roots of P. densiflora form simple and dichotomous lateral roots with dense mycelia. In addition, inoculation with X. affine NIFoS 2716 promoted root and shoot developments.

• Mycobiology
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• v.47 no.4
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• pp.506-511
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• 2019

We investigated the antifungal activities of an endophytic fungus identified as Acaromyces ingoldii, found on a loblolly (Pinus taeda L.) pine bolt in Louisiana during routine laboratory microbial isolations. The specific objectives were to determine the inhibitory properties of A. ingoldii secondary metabolites (crude extract) on the mycelial growth of a brown-rot fungus Gloeophyllum trabeum and a white-rot fungus Trametes versicolor, and to determine the effective concentration of A. ingoldii crude preparation against the two decay fungi in vitro. Results show the crude preparation of A. ingoldii from liquid culture possesses significant mycelial growth inhibitory properties that are concentration dependent against the brownrot and white-rot fungi evaluated. An increase in the concentration of A. ingoldii secondary metabolites significantly decreased the mycelial growth of both wood decay fungi. G. trabeum was more sensitive to the inhibitory effect of the secondary metabolites than T. versicolor. Identification of specific A. ingoldii secondary metabolites, and analysis of their efficacy/specificity warrants further study. Findings from this work may provide the first indication of useful roles for Acaromyces species in a forest environment, and perhaps a future potential in the development of biocontrol-based wood preservation systems.

• Mycobiology
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• v.45 no.4
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• pp.240-254
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• 2017

Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity ($a_w$) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and $a_w$. This review discusses the effects of temperature and $a_w$ on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.

• Mycobiology
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• v.31 no.4
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• pp.221-225
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• 2003

Effect of ethanolic extracts of Lawsonia inermis, Azadirachta indica, Vinca rosea, Tagetes patula, Ocimum sanctum, Colocasia antiquorum, Adhatoda vasica, Moringa oleifera, Datura metel and Curcuma longa leaf on conidial germination, mycelial growth and sporulation of Aspergillus flavus, A. niger and A. fumigatus were examined. The conidial germination of A. flavus and A. fumigatus were most inhibited by the extract of L. inermis, while that of A. niger was inhibited by A. indica. Other tested plant extracts have a good effect on conidial germination on the selected fungi. The highest mycelial growth of A. flavus(37 mm) was found in V. rosea, but in case of A. niger and A. fumigatus it(38 and 39 mm) was found in D. metel. The lowest(4, 9 and 6 mm) respectively mycelial growth of these fungi found in L. inermis. The highest sporulation($75{\times}10^4/ml$) of A. flavus was counted in V. rosea, but in case of A. niger and A. fumigatus those($45{\times}10^4$ and $55{\times}10^4/ml$) were in D. metel and the lowest($5{\times}10^4,\;12{\times}10^4\;and\;9{\times}10^4/ml$) respectively sporulation of these fungi counted in L. inermis plant extract medium.

• The Korean Journal of Pharmacology
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• v.9 no.1
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• pp.59-63
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• 1973

Although numerous drugs are available for the treatment of superficial fungi infections of skin, and yet the clinical effects of most of such drugs are not satisfactory. In the hope of searching for effective drugs for superficial fungi infections, the authors observed fungistatic effects of Pyrethri Flos, a common herb in Korea, with water extract (PFWE), ethanol extract (PFEE), and methanol extract (PFME) from Pyrethrum cinerariaefolium V. In in vitro studies, the spores of fungi were inoculated on Sabouraud's glucose agar media which contained Pyrethri Flos extracts in each concentrations of $500\;{\mu}g/ml$, $1,000\;{\mu}g/ml$ and $5,000\;{\mu}g/ml$ respectively, and the growth of the fungi was observed for 3 weeks. The species of the fungi used in these experiments were Epidermophyton floccosum, Microsporum canis, Microsporum nanum, Microsporum gypseum, Microsporum cookei, Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans and Trichophyton verrucosum. The results of these studies were as follows; 1. The growth of M. nanum & T. rubrum was slightly inhibited by PFWE $500\;{\mu}g/ml$, and the growth of M. nanum, M. cookei & T. rubrum was slightly inhibited by PFWE $1,000\;{\mu}g/ml$. The growth of E. floccosum, M. gypseum & M. cookei was slightly inhibited, however the growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited by PFWE $5,000\;{\mu}g/ml$. With $500\;{\mu}g/ml$ of PFEE, the growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited, and moderate inhibition of M. cookei growth and slight inhibition E. floccosum & M. gypseum were observed. The growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited, and the growth of E. floccosum, M. gypseum & M. cookei was moderately inhibited by PFEE $1,000\;{\mu}g/ml$. Significant inhibitions of the growth of E. floccosum, M. canis, M. nanum, M. gypseum, M. cookei, T. mentagrophytes, T. rubrum & T. tonsurans were observed by PFEE $5,000\;{\mu}g/ml$. 3. The growth of E. floccosum & M. cookei was moderately inhibited, and the growth of M. canis, M. nanum, M. gypseum, M. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited by PFME $500\;{\mu}g/ml$. But the growth of E. floccosum, M. canis, M. nanum, M. gypseum, M. cookei, T. mentagrophytes, T, rubrum & T. tonsurans was significantly inhibited, and the growth of T. verrucosum was slightly inhibited in both PFME $1,000\;{\mu}g/ml$ and $5,000\;{\mu}g/ml$.

• Mycobiology
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• v.31 no.2
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• pp.86-94
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• 2003

The effect of four sub-lethal concentrations(400, 800, 1,200 and 1,600 ${\mu}g/ml$) of three amino acids such as isoluecine, aspartic acid and phenylalanine on vegetative growth and sexual and asexual reproduction of Achlya racemosa, A. proliferoides and Saprolegnia furcata was investigated. The density of vegetative growth and diameters of vegetative colonies of species of the Oomycetes fungi decreased with rising the concentration of the applied amino acid. Vegetative hyphae of treated fungi almost appeared branched in case of S. furcata, thick in case of A. racemosa and distorted in case of A. proliferoides as compared with control. The different treatments with amino acids depressed both sporangial formation and discharge, which were dependent on the tested species of zoosporic fungi, the amino acid and its dosage. Phenylalanine was the most effective amino acid in inhibiting sporulation and S. furcata was the most sensitive fungal species. Aspartic acid and isoleucine stimulated germination of discharged spores through the formation of germlings. Gemmae formation by the three fungi was reduced at the low concentrations of amino acids and nearly missed at high concentrations. Sex organs(oogonia and antheridia) were affected partly; rudiment oogonia were observed at low concentrations(400 and 800 ${\mu}g/ml$) and disappeared at higher concentrations, whereas antheridial branch formation was stimulated as the fungi were treated with isoleucine and to some extent phenylalanine.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.1
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• pp.7-12
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• 2010

To determine the optimal isolation conditions of the entomopathogenic fungi from soil, we compared their growth characteristics with non-entomopathogenic fungi on agar media containing various concentrations of cooper (II) chloride ($CuCl_2$) or dodine. The result showed that dodine medium is more selective, and the optimal concentration of dodine is determined with $50{\mu}g$/ml. We could isolate several putative entomopathogenic fungi from soil using this, and identify them using ITS analysis. As a result, 64% fungi were identified as typical entomopathogenic fungi. This selective medium may be useful to the rapid and simple isolation of entomopathogenic fungi from soil.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.3
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• pp.9-14
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• 2004

The useful fungi which secret extracellular enzymes was selected for deinking agent of old newsprint. Five fungal strains were isolated from a paper mill soil ground. The CMCase, FPase and xylanase activities of fungi on the liquid culture were investigated at optimal growth conditions. The results of this study were as follow: The optimal pH and temperature for culture growth were 4～8 and 27～$35^{\circ}C$, respectively. For screening of extracellular enzymes at optimal culture conditions the optimal culture period were less than 6-7 days. Fusarium pallidoroseum and Aspergiilus niger which shows relatively higher CMCase, FPase and xylanase activities than the other species were selected for further enzymatic deinking research.