• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.428-432
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• 1999

This study was performed to investigate the possible effect of sunlight on the reduction or degradation of mycelia and aflatoxins. The mycelia and aflatoxins were produced by Aspergillus parasiticus ATCC 15517 in a yeast-extract sucrose broth (YES) and potato-dextrose agar (PDA) and then exposed to sunlight. The weight of mycelia was decreased to 76.8% in 8 hours and to 66.7% in 168 hours(p<0.05). The total aflatoxin level was significantly decreased to below 50% (46.3% in the YES broth and 49.6% in the PDA) in 8 hours (p<0.05). After 168 hours, a 90.4％ degradation of aflatoxin in the YES broth and a 77.2% degradation of aflatoxin in the PDA was observed, respectively (p<0.01). The results showed that the degradation ratios of total aflatoxin level increased with increased exposure time to sunlight. These results indicate that sunlight could be an effective factor in aflatoxin degradation although its effect on mycelia was less pronounced.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1093-1097
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• 2004

This study was aimed to establish the amount of enzose (corn dextrose) for optimum N fixation in urea treated corncobs (UTC) and their dietary effect on nutrient intake, digestibility and milk yield in crossbred cows. Corncobs were treated with 5% urea and ensiled in laboratory silos with 0, 2, 4 and 6% enzose for 15 days. Total nitrogen (N), neutral detergent fiber (NDF) and neutral detergent insoluble N contents were increased in UTC with the level of enzose. Five early lactating crossbred cows (Sahiwal$\times$Holstein Frisian) were used in a 5$\times$5 Latin Square Design to see the influence of UTC ensiled with 6% enzose on nutrient intake, digestibility, milk yield and its composition. Five iso-nitrogenous and iso-caloric diets were formulated. The UTC30 (control), UTC40, UTC50, UTC60 and UTC70 diets contained 30% UTC ensiled without enzose and 40, 50, 60, 70% UTC ensiled with 6% enzose, respectively. Dry matter, NDF and ADF intakes were increased with the increasing level of UTC ensiled with enzose in the diets of cows. Dry matter, NDF and ADF digestibilities were significantly higher with diets containing UTC ensiled with enzose. Milk yield was significantly higher in cows fed UTC70 compared to those fed on other diets. The milk crude protein percentage was significantly different across treatments. However, milk fat, total solids, solid not fat, true protein and non-protein nitrogen contents of milk remained similar across all diets. Ensilation of UTC with 6% enzose improved the nitrogen retention and thus enhanced the feeding value of UTC for lactating cows.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.206-209
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• 2002

For the expression of CGTase gene(cgtS) kom Bacillus stearothemophilus NO2 in Saccharomyces cerevisiae, cgtS gene was subcloned into the Eschepichia coll-yeast shuttle vector, pVT103-U. The constructed plasmid, pVT-CGTS was introduced to 5. cemi-siae 2805 cell, and then the cgtS gene under the control of adhl promoter was successfully expressed in the yeast transformant and 87% of the total activity was detected into the fermentation medium. Therefore, the signal peptide of B. stearothemephilus NO2 CeTase showed high secretion efficiency in 5. cerevisiae. Optimal conditions of the recombinant yeast cell f3r expression of CGTase was achieved, when 5. cerevisiae 2805/pv7-CGTS was cultivated on YP medium at 2% dextrose, pH 5.5,$30^{\circ}C$ and the expression level of CGTase was 0.624units/mL for 48 h culture.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.307-314
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• 2018

The goal of this study was to investigate the microbiological characteristics of the ethanol-producing wild yeast, Aureobasidium pullulans P-1, isolated from flowers growing near the Yedang reservoir, Chungnam province, Korea, and in addition, to optimize its fermentation ability for the production of Makgeolli. A. pullulans P-1 was oval-shaped, and formed ascospores and pseudomycelium. The P-1 strain was a halophilic and sugar tolerant yeast which grew in 15% NaCl and 50% glucose-containing yeast extract-peptone-dextrose media. The P-1 strain was also resistant to 20% ethanol. Changes of the physicochemical properties during Makgeolli fermentation by A. pullulans P-1 were investigated. A maximum of 8.45% ethanol was obtained when a mixture of cooked rice, 150% water, and 35% ipguk per cooked rice was fermented by 5% A. pullulans P-1 culture broth at $25^{\circ}C$ for 10 days. Antihypertensive angiotensin I-converting enzyme inhibitory activity in the Makgeolli ferment produced by A. pullulans P-1 reached a high of 71.1% after 10 days.

• Journal of Veterinary Clinics
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• v.31 no.4
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• pp.322-324
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• 2014

Candidiasis caused by Candida albicans is a localized mucocutaneous disease. It occurs worldwide in various kinds of animals. A 7-year-old male spotted seal weighing 98 kg showed facial skin lesions. The present case was characterized by erythematous, thickened, and alopecic skin lesions in the periocular region and on the commissure of the lower lip. For diagnosis, skin scraping and culture of samples from the facial skin lesions were done. Colonies were cream-colored and glistening after 3 days of culture on Sabouraud dextrose agar. Typical yeast-like cells were observed by microscopic inspection after Gram staining. Recovery was achieved with itraconazole (1 mg/kg SID) for 7 days, repeated three times at 2-week intervals.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.269-274
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• 2009

Rearing media were selected for the production of sterile larvae of greenbottle blowfly, Phaenicia (=Lucilia) sericata (Meigen) which is widely used in maggot therapy. Eight media available in the market were used in this study. Egg hatchability was not different among the media. Survivorship of the larvae was higher in blood agar (BA), sabouraud dextrose agar, and brucella blood agar than the others. A higher content (20${\sim}$40%) of sheep blood in BA and chocolate agar increased the survivorship of larvae. The eggs and the early 3rd larvae could be stored for 12 days at $8^{\circ}C$ and for 15 days at $6^{\circ}C$ without decrease in hatchability and larval survivorship, respectively.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.691-696
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• 2000

Syzygites megalocarpus occurred on the fruit bodies of Tricholoma matsutake, Leccinum rugosiceps, Pulveroboletus ravenelii, Russula emetica, and Amanita pseudoporphyria in the field. We could select Malt Extract Agar, Mueller Hinton Medium and Potato Dextrose Agar as optimal media among eight media. Syzygites megalocarpus showed an optimal temperature around $23^{\circ}C$ with optimal pH 6.0. Growth of S. megalocarpus on PDA was inhibited by 36.5% at 5% NaCl compared with without NaCl and did not grow at more than 8% NaCl in 2 days after inoculation. However, it grew 1.1 cm in 10% NaCl in 5 days after inoculation. Growth of Tricholoma matsutake on PDA was inhibited by increasing contration of NaCl and did not nearly grow at 2.5% NaCl in 60 days after inoculation. Because S. megalocarpus grew at high concentration of NaCl, we concluded that NaCl should not use for controlling S. megalocarpus on the fruit body of T. matsutake.

• Research in Plant Disease
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• v.17 no.2
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• pp.225-227
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• 2011

The stem rot of Chrysanthemum zawadskii var. latilobum occurred in the landscape field of Sanggwan-myeon, Wanju-gun, Jeonbuk, Korea in September 2009. The typical symptoms of the disease were water-soaking and dark brown rot on the stem, wilting and blighting. Most infected plants died of the disease. White mycelial mats were spread over lesions and brown sclerotia were formed on stems and near soil surface. The sclerotia were spherical or irregular, 0.8-3.5 (mean 1.8) mm in size on potato dextrose agar, brown in color. The optimal temperature range of hyphal growth was $25-30^{\circ}C$ and the hyphal diameter was 4-9 ${\mu}m$. Clamp connections were observed in the hyphae of the fungus grown on potato dextrose agar. Pathogenicity of the casual organism was provided on C. zawadskii according to Koch's postulate. The fungus was identified as Sclerotium rolfsii on the basis of mycologiclal characteristics and pathogenicity test to host plants. This is the first report on the stem rot of C. zawadskii caused by S. rolfsii in Korea.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.674-683
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• 2019

Some species of the Trichoderma genus are reported as the major problem in oak wood mushroom production in Korea. In spite of economic loss by the fungi, scientific information on airborne Trichoderma species is not much available. To generate information for disease management development we analyzed airborne Trichoderma. A total of 1,063 fungal isolates were purely obtained from indoor air sampling of cultivation houses used for oak wood mushroom using sawdust media. Among the obtained isolates, 248 isolates were identified as Trichoderma fungi including T. harzianum, T. atroviride, T. citrinoviride, and T. pseudokoningii, by morphological and molecular analysis. T. harzianum was dominant among the four identified species. All the four Trichoderma species grew fast on solid nutrient media tested (potato dextrose agar [PDA], malt extract agar [MEA], Czapek's Dox + yeast extract agar [CYA] and cornmeal dextrose agar). Compact mycelia growth and mass spore production were better on PDA and CYA. In addition, T. harzianum and T. citrinoviride formed greenish and yellowish mycelium and spores on PDA and CYA. Greenish and yellowish pigment was saturated into PDA only by T. pseudokoningii. These four Trichoderma species could produce extracellular enzymes of sawdust substrate degradation such as β-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease. Their mycelia inhibited the growth of oak wood mushroom mycelia of two tested cultivars on dual culture assay. Among of eleven antifungal agents tested, benomyl was the best to inhibit the growth of the four Trichoderma species. Our results demonstrate that the airborne Trichoderma fungi need to be properly managed in the cultivation houses for safe mushroom production.

• Research in Plant Disease
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• v.26 no.1
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• pp.48-52
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• 2020

In July 2019, typical rot symptom was observed on peach fruits harvested from the fields at Andong, Korea. As the disease progressed, white and purple colored mycelial mat developed on the surface of the infected fruits. A causal pathogen was isolated from the infected fruit and cultured on potato dextrose agar media for identification. Fungal colonies on potato dextrose agar produced 3 pigments, including purple, yellow, and white colors. The isolate incited fruit rot symptoms on artificially inoculated peach fruits, from which the same fungus was isolated, fulfilling Koch's postulates. Based on the morphological characteristics and sequence analysis of rDNA internal transcribed spacer, translation elongation factor 1-alpha, and β-tubulin, the causal agent of the disease was identified as Fusarium avenaceum. This study is the first report of fruit rot of peach fruits caused by Fusarium avenaceum in Korea.