• Microbiology and Biotechnology Letters
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• v.28 no.5
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• pp.303-308
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• 2000

The character-istics of the volatile flavor components of traditional Korean Nuruk produced by Aspergillus oryze NR 3-6 and Penicillium expansum NR 7-7 were investigated. Volatile flavor of Nuruk was identified twenty-one components by gas chromatography-mass spectronmeter. Major flavor components were alkanes such as tridecan, tetradecan, penta-decane, hexadecane, heptadecane, octadecan, undecane, and dodecane.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.281-287
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• 2013

In Korea, isolated cultivation has been implemented for 102 genera, including about 250 species, each of which has underwent microscopic inspection, cultivation of bacteria in selective medium, analysis of physiology and biochemistry, enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). The number of isolated microorganisms was 8,307 in the period of 2005-2012, and bulbs and tubers had the greatest diversity of microorganisms, of 5,165 (62.2%), followed by 2,119 (25.0%) sapling, 796 (9.6%) seed, 150 (1.8%) cutting slip, 70 (0.8%) branch graft and 7 (0.1%). The number of cases which were disqualified were 413 (4.97%), after the detection of 47 disease causing species of microorganism. Viruses predominated, with 27 species, followed by 16 fungi, a viroid, a Chromalveolata and 2 further species. Top on the list of detection was Arabis mosaic virus (77 cases), followed by Tobacco rattle virus (70 cases), Lily symptomless virus (46 cases) and Penicillium expansum (46 cases).

• Research in Plant Disease
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• v.9 no.4
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• pp.229-236
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• 2003

The 1080 epiphytic bacteria obtained from 370 samples of pome and stone fruits including apple, pear, peach, grape, apricot and Chinese quince were screened for antagonistic activity against postharvest pathogens, Penicillium expansum, Alternaria alternata and Botrytis cinerea. Among tested antagonistic bacteria, eight bacterial isolates inhibited mycelial growth of the postharvest pathogens and were identified as Bacillus amyloliquefaciens (three strains), B. megaterium, B. subtilis var. gladioli, B. licheniformis, B. pumilus and Serratia marcescens based on biochemical characteristics and utility of carbon and nitrogen compounds (Biolog system). Eight carbohydrates were evaluated for their effect on mycelial growth and germination of the postharvest pathogen, P. expansum to select nutrients for enhancing bio-control efficacy. The growth of four selected antagonists, B. amyloliquefaciens P43-2, B. amyloliquefaciens A71-2, B. licheniformis P94-1, and S. marcescens P76-9 were also tested. As a result, 1% glucose (w/v) strongly stimulated growth of the antagonists, suppressed mycelial growth of the postharvest pathogen, and had a little comparatively stimulatory effect on germination of the the postharvest pathogen. It was confirmed that the addition of 1% glucose (w/v) greatly enhanced biocontrol effect of B. amyloliquefaciens P43-2, B. licheniformis P94-1, and S. marcescens P76-9. Application of B. amyloliquefaciens P43-2, B. licheniformis P94-1, and S. marcescens P76-9 with the addition of 1% glucose (w/v) increased the control efficacy up to 48%, 46%, 14% compared with those of the antagonists without glucose, respectively. When the antagonists were applied to control postharvest disease caused by P. expansum in apple wounds, the population of B. amyloliquefaciens P43-2 and B. licheniformis P94-1 increased until 4 days after inoculation (DAI) of the antagonists and then decreased from 10 DAI. Meanwhile the population of S. marcescens P76-9 decreased at early stage (4 DAI), but increased from 7 DAI, and finally maintained constantly until 10 DAI in apple wounds.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.253-259
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• 2010

In vitro and in vivo mycofumigation effects of the volatileproducing fungus Nodulisporium sp. CF016 isolated from stem of Cinnamomum loureirii and the role of its volatile compounds were investigated against phytopathogenic fungi. The volatile compounds produced by Nodulisporium sp. CF016 inhibited and killed a wide range of plant and storage pathogens including to Pythium ultimum, Rhizoctonia solani, Fusarium oxysporum, Phytophthora capsici, Sclerotinia sclerotiorum, Colletotrichum coccodes, Magnaporthe oryzae, Alternaria panax, Botrytis cinerea and Penicillium expansum. Mycofumigation with wheat bran-rice hull cultures of Nodulisporium sp. CF016 showed in vivo antifungal activity against gray mold caused by B. cinerea and blue mold caused by P. expansum of apple. The most abundant volatile compound produced by Nodulisporium sp. CF016 was $\beta$-elemene followed by 1-methyl-1,4-cyclohexadiene, $\beta$-selinene and $\alpha$-selinene. Nodulisporium sp. CF016 could be an attractive mycofumigant in controlling postharvest diseases of various fruits including apple.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.176-180
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• 2015

Postharvest diseases cause losses in a wide variety of crops around the world. Irradiation, a useful nonchemical approach, has been used as an alternative treatment for fungicide to control plant fungal pathogens. For a preliminary study, ionizing radiations (gamma, X-ray, or e-beam irradiation) were evaluated for their antifungal activity against Botrytis cinerea, Penicillium expansum, and Rhizopus stolonifer through mycelial growth, spore germination, and morphological analysis under various conditions. Different fungi exhibited different radiosensitivity. The inhibition of fungal growth showed in a dose-dependent manner. Three fungal pathogens have greater sensitivity to the e-beam treatment compared to gamma or X-ray irradiations. The inactivation of individual fungal-viability to different irradiations can be considered between 3-4 kGy for B. cinerea and 1-2 kGy for P. expansum and R. stolonifer based on the radiosensitive and radio-resistant species, respectively. These preliminary data will provide critical information to control postharvest diseases through radiation.

• Journal of Life Science
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• v.27 no.6
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• pp.688-693
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• 2017

Antifungal bacterium against Colletotrichum coccodes causing black dot disease of potatoes and anthracnose of tomatoes was isolated from sewage sludge. The isolate showed a 99% sequence homology of partial 16S rRNA of Bacillus methylotrophicus CBMB205 and Bacillus amyloliquefaciens subsp. plantarum FZB42. The isolate was identified as Bacillus sp. SW29-2, using the neighbor-joining phylogenetic tree, BlastN sequence analysis, and morphological and cultural characteristics. Bacillus sp. SW29-2 is an aerobic, Gram-positive, endospore-forming bacterium, of which the morphological and physiological characteristics were the same as those of type strain B. lichniformis CBMB205, except for the cell growth of over 4% NaCl. The cell growth of the temperature and the initial pH of the medium was shown at $18-47^{\circ}C$ (opt. ca. $38^{\circ}C$) and 3-9 (opt. ca. 6.0), respectively. The inhibition size (diameter) of Bacillus sp. SW29-2 against four strains of C. coccodes ranged from 23 to 29 mm. Also, the isolate showed antifungal activity against penicillium rot-causing Penicillium expansum in apples. Thus far, any report on the antifungal activity of Baciilus spp. against C. coccodes has not been found. These results suggest that the Bacillus sp. SW29-2 isolate could be used as a possible biocontrol agent against C. coccodes, and further applied to other plant pathogenic fungi.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.47-51
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• 2006

Microorganisms involved in decaying Fuji apples during storage were investigated. Seven pathogens were isolated from the rotted fruits. Penicillium spp. was derived from 65-75% of decayed apples with P. expansum being dominant species. Effects of mild heat treatment on microbial reduction, respiration, and texture characteristics in Fuji apples were examined through hot water dipping at $40-65^{\circ}C$ for varied timε periods. Initial counts of total microorganisms and moulds in fresh fruits s showed 4.75 and 4.66 log CFU/g in a stem, as well as 5.35 and 4.32 log CFU/g in a calyx, respectively. The heat treatment at $40^{\circ}C$ for 180 min significantly reduced the population of total microorganisms and moulds in the fruits. Respiration rate of the apple fruits increased immediately after heat treatment and then returned to the normal level during storage. The rates of ethylene production in the fruits treated at $40-50^{\circ}C$ were maintained lower than that of the untreated control. The fruits treated at $40^{\circ}C$ showed slightly greater flesh firmness than the other apple samples during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.789-799
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• 1998

Literatures on microorganisms of traditional Korean nuruk published since 1945 were reviewed in this paper. Traditional Korean nuruk consists of raw barley and various grains. Traditional Korean nuruk consists of unbolied raw barely and various grains. They are ground to paste and moistened, and then naturally inoculated by airborne microorganisms. Therefore, many kinds of microorganisms such as fungi, yeast, and bacteria grwo in nuruk. Since 1945, new 14 species of Aspergillus and 9 species of Penicillium have been identified from traditional Korean nuruk. Total number of fungal species identified so far is now up to 38 species among 12 different genus. Among newly isolated fungal species, Aspergillus penicilloides and Penicillium, expansum showed not only high production rate of acid and amylase but also extreme stability of the enzyme at room temperature for 3 months. As examples of newly isolated yeast species, there are 5 species of Candida, 4 species of Hansenula, 1 species of Pichia and 1 species of Schizosaccharomyces. Total number of yeast species isolated so far is up to 18 species from different 8 genus. Newly isolated bacteria, were Bacillus pumilus, Lactobacillus casei and Leuconostoc mesenteroides.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.456-464
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• 1998

For the standardization and quality improvement of traditional Korean Nuruk, 10 strains of fungi, which were isolated from Nuruks and showed good productivity of the saccharogenic and dextrinogenic enzymes, acid and flavor, were selected and their enzymological characteristics and identification were carried out. Aspergillus spp. and Rhizopus sp. showed a high liquefying activity without regard to cultivation time, whereas the majority of strains except for Rhizopus sp. had decreasing saccharifying activity in proportion to the increase in cultivation time. Aspergillus spp. No.17-2, No.17-6 and Rhizopus sp. No.18-1 showed high liquefying and saccharifying activity after 15 and 30 day cultivation. The optimum temperature of most of these saccharogenic and dextrinogenic enzymes was from 40$^{\circ}C$ to 60$^{\circ}C$, and their optimum pH was extensive between pH 3 and pH 11. But Penicillium spp.(2 strains) and Rhizopus sp. showed low activity under the alkalic and acidic conditions. Among these isolated strains, 5 strains which had shown the high productivity of materials were identified as Aspergillus oryzae NR3-6 and Aspergillus oryzae NR17-6, Aspergillus penicilloides NR12-1, Penicillium expansum NR7-7 and Rhizopus oryzee NRl8-1, respectively. Five kinds of mixed culture were carried out and all of them showed a better productivity of saccharogenic and dextrinogenic enzymes than single culture. These results indicate that it is possible to make traditional Korean liquors of good quality by using these fungi.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.82-88
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• 1984

Fruit rot and blister canker, a disease of apple occurring severely in Korea has been studied for correct identification of the syndrome In fruit and apple trees. Among the fungi isolated from blister cankers, rough barks or fruits showing rotting of 7 different host species were Botryosphaeria berengeriana (pycnidial stage. Dethiorella mali), Penicillium expansum and Alternaria sp. from apple rots and Phomopsis sp. from pear fruit rots. The most dominant isolates were B. berengeriana. Ten isolates of D. mali were grouped in to two conidial types based up mycelial growth rate, growth habits and mycelial coloration on PDA. None of 10 isolates was chromogenic. Pycnidia in apple stems, stromatic, dark brown, globose or subglobose and the measuring were $103.5-287.5{\mu}\times92.0-287.5\mu$. The pycnidia contained hyaline, nonseptate, fusiform conidia. The sizes of pycnidiospore of isolates obtained from apple twig were $4.3-7.2{\mu}\times20.0-31.5{\mu}(average\;5.9\times25.4\mu)$. Some conidia of this fungus from apple, pear, peach and ornamental cherry showed 1-,2-,3-septate before or during germination. Microconidia were observed in pycnidia on PDA and fruit lesion of inoculated host. Symptoms on leaves and fruits were contoured brown spots when inoculated. Wart-like protuberance were formed on the surface of apple and pear. Canker appeared on branches of peach and ornamental cherry inoculated.