• Korean Journal of Microbiology
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• v.35 no.1
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• pp.53-60
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• 1999

The biodegradation of recalcitrant polycyclic aromatic hydrocarbon, pyrene was investigated in microcosm simulating the beach sand and seawater. The natural biodegradation rates of pyrene were between 30-2,200 ng/g(ml)/day in beach sand and seawater when the pyrenc loading rates were 100- 1,000 ppm at 5-$20^{\circ}C$. The effects of the inoculum size, pyrene concentralion, incubation temperature and surfactant addition were investigated in fertilized (Inipol EAP 22) samples. Generally the biodegradation in beach sand was higher than that in seawater. A mixed inoculum (Pseudomonus, Acinetobacter, Moruxella) showed the 3,120 nglglday of biodegradation rate in beach sand with 200 ppm pyrene, which was 7.8 times higher than the natural biodegradation rate. The highest transformation rate, 4,860 ng/g/day was obtained in the bioaugmented beach sand (1,000 ppm pyrene). The glucose and surfactant addition to enhance the removal have negatively influenced on the biodegradation of pyrene. In case ol surfactants, CMC (critical micell concentration) might bc the control factor for the biodegradation.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.1-6
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• 1977

The 'Kresek' disease in Korea caused by Xanthomonas oryzae was first found from eight counties in Jeon-nam and Kyungnam province in 1976. The study has been carried mainly on the grouping of pathogens and reproduction of the symptoms on Milyang #23, the variety had shown severe damages at the fields, by using the isolates from Hwa-sun and Kwang-san counties where the first epidemics took place. 1. The 'Kresek' disease was found mainly on Milyang #23, a new variety, at Hwa-sun, Mu-an, Kang-jin. Yung-am, Gog-sung counties in Jeon-nam province and Jin-yang county in Kyung-nam province. 2. The groups of 'Kresek' causing pathogens were the same of those producing bacterial leaf blight symptoms such as group I , II, IN and V of Xanthomonas oryzae. 3. Seventeen out of 21 isolates from Hwa-sun county where the first and severe damage found belonged to group IV, 2 to group II and 2 to group V All of 5 isolates from Kwang-san county belonged to the group IN. 4. The 'Kresek' type symptom could reproduced within 5 days after inoculation to seedlings by using root tut, spray and needle inoculation methods. j. The most of effective method for the inoculation was root cut, and then were spray and needle method. respectively. The higher concentration of inoculum produced the higher disease incidence.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.312-321
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• 2014

Tricholoma bakamatsutake is one of the edible ectomycorrhizal mushrooms as an allied species of Tricholoma matsutake. This is the first report on physical characteristics of T. bakamatsutake strains collected from Quercus mongolica forests in Korea. The pure cultures of these strains were isolated from the tissues of fruit bodies and the culture characteristics were investigated under different conditions (media, temperatures, nitrogen sources). Most strains showed the highest mycelial growth on potato dextrose agar (PDA) at 20 or $25^{\circ}C$. Two strains of T. bakamatsutake preferred the ammonium-form rather than the nitrate-form as an inorganic nitrogen source. T. bakamatsutake showed significantly slower mycelial growth when compared with T. matsutake from a Korean forest, although the optimum culture conditions for the two allied species were similar. We also tested the ability to form mycorrhizae as well as cellulase activity of T. bakamatsutake. All strains showed cellulase activity on a carboxymethylcellulose (CMC) agar plate. The mycorrhizae on axenic Pinus densiflora seedlings were formed by two strains of T. bakamatsutake after 3 or 8 months of inoculation. P. densiflora seedlings inoculated with T. bakamatsutake had a much higher biomass than un-inoculated seedlings.

• Microbiology and Biotechnology Letters
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• v.6 no.2
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• pp.59-63
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• 1978

The Screening of fungi producing naringinase was done. A strain of Aspergillus midulans showed the highest naringinase activity among 447 strains those were isolated from soil, spoiled citrus friuts and stock cultures. The cultural Conditions of Asp. nidulans for production of naringinase were studied. A strain of Asp. nidulans showed higher activity when it was cultivated at 30$^{\circ}C$ for 3 days on wheat bran media supplemented with 2.0％ naringin, 0.2％ (NH$_4$)$_2$ SO$_4$ and 0.2％ CaCO$_3$.

• Korean Journal of Microbiology
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• v.43 no.2
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• pp.142-146
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• 2007

Panax ginseng has been drawing world-wide attention since it was used for medicinal purposes and its effects was discovered in scientific manners. However, it is necessary to develope new ginseng products as functional foods to compete with western ginseng. Fermented ginseng could be an excellent solution, where useful probiotics are provided and ginsenosides are specifically transformed to functional forms. In this study, we investigated the growth and ginsenoside biotransformation by 21 Bacillus strains isolated from Chongkukjang and 12 lactic acid bacteria. 2.5% (w/v) and 1% (w/v) of ginseng were used in culture media containing only ginseng powder as a sole nutrient source, and their biotransformation abilities were tested after the growths were checked. All used Bacillus strains and lactic acid bacteria were able to grow well in ginseng powder media at higher levels than $10^{7}\;CFU/ml$. Most of Bacillus strains displayed ginsenoside transformation in a strain-specific manner. Therefore, the results of this study demonstrated that the strains tested in this study could be used as potential starters for the ginseng fermentation.

• Applied Biological Chemistry
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• v.51 no.1
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• pp.17-23
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• 2008

In order to prevent wine quality deterioration caused by strong sour taste from raw and other materials during fermentation of wild grape wine, the various mixed cultures conditions of the deacidification fermentation and the alcohol fermentation process by inoculation of mixed strains were investigated. As a result of mixed cultures process after the inoculation of Schizosaccharomyces pombe and Schizosaccharomyces japonicus with each deacidification fermentation strain in a culture of Saccharomyces sp. SMR-3 which was used in the alcohol fermentation strain of wild grape, cultures for 12 days at $22^{\circ}C$ with Saccharomyces sp. SMR-3 and Schizosaccharomyces pombe resulted in the maximum alcohol content at $15.8{\pm}0.2%$ and the minimum with the acidity of $0.44{\pm}0.02%$, the total organic acid of $648.96{\pm}7.14$ mg% and malic acid of $99.30{\pm}1.24$ mg%. Mixed cultures with Saccharomyces sp. SMR-3 and Schizosaccharomyces pombe under the optimal condition for the deacidification fermentation of wild grape wine showed 2% higher alcohol content, 51.65% lower acidity, 48.02% lower total organic acid, and 81.12% lower malic acid than a single culture of Saccharomyces sp. SMR-3.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.369-379
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• 2020

Black mold was frequently observed on tomatoes grown in a greenhouse in Suwon, Korea in July 2018. The incidence of the disease was 5.0-25.0% (average 12.3%) and 2.0-7.0% (average 3.7%) in the context of tomato and cherry tomato fruits, respectively. Sixteen single-spore isolates of Alternaria sp. were obtained from the diseased fruits and investigated for their morphological characteristics. Among the isolates, eight were used for sequencing analysis. All of the isolates were identified as Alternaria alternata based on their morphological and molecular characteristics. The pathogenicity of four isolates of A. alternata was investigated using three varieties each of tomato and cherry tomato via artificial inoculation. All of the isolates induced black mold symptoms on the inoculated tomato fruits. Notably, the symptoms were similar to those observed in the greenhouse. However, the pathogenicity tests revealed that different tomato varieties presented distinct patterns of susceptibility to the isolates. This is the first report of A. alternata causing black mold on tomato fruits in Korea.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.429-436
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• 2005

As Sclerotinia sclerotiorum causing cucumber sclerotinia rot was the fastest in the mycelial growth at $25^{\circ}C$, its pathogenicity was strong at the same temperature among several temperatures. All the isolates of Sclerotinia sclerotiorum showed a strong pathogenicity against cucumber fruits, which was confirmed by a disk assay and a wound assay. A wound assay was superior to a disk assay to develop the assay system for assessing the fungicidal activity of several fungicides against Sclerotinia sclerotiorum. In a disk assay, it was very difficult to assess the fungicidal activity, because the pathogenicity of isolates used in the experiment was very strong. At 500 and $3.0{\mu}g/mL$, the activity of dichloflouanid and the mixture of carbendazim and diethofencarb against cucumber sclerotinia rot was 14.3 and 42.3%, respectively, by using a disk assay. However, at same concentration two fungicides showed the high controlling activity as 100 and 92.5%, through a wound assay in a laboratory. Also, the activity of two fungicides was good against cucumber sclerotinia rot in the greenhouse where cucumber plants were cultivated in the field, showing the control value as 91.1 and 82.9% at 100 and $825{\mu}g/mL$, respectively. All the isolates of Sclerotinia sclerotiorum from cucumber fruits sampled in the polyvinyl house were subjected to monitoring for the resistance to 7 fungicides. The $EC_{50}$ value of 7 fungicides was as follows: fenhexamid; $0.13{\mu}g/mL$, procymidon and iprodione; 0.18 and $0.24{\mu}g/mL$, carbendazim and the mixture of carbendazim and diethofencarb; 0.13과 $0.05{\mu}g/mL$, iminoctadine and dichlofluanid; 1.94 and $8.95{\mu}g/mL$. Ultimately it was not found that resistant isolates of Sclerotinia sclerotiorum were appeared in the field.

• Pediatric Infection and Vaccine
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• v.16 no.1
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• pp.80-86
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• 2009

Purpose : This study was performed to determine the clinical course of BCG lymphadenitis. Methods : Between May 2005 and April 2009, the medical records of 33 patients with BCG lymphadenitis were retrospectively reviewed. If needed, needle aspiration was recommended without surgical resection or antituberculous medication. Results : Of the 33 patients who were identified, 21 were males and 12 were females. Among the 33 patients, 32 were full-term babies. The mean age was 6 months (range, 2-35 months) and the most prevalent site of the lesion was the left axilla. BCG lymphadenitis was observed 1-34 months after BCG vaccination, mostly 1-6 months after vaccination. The size of the enlargement was generally 1-3 cm. The strains were identified as French (n=14), Danish (n=7), and Tokyo (n=12). BCG lymphadenitis regressed spontaneously in 19 patients. After 1-5 needle aspirations, 14 patients recovered completely. Complete regression of lymphadenitis was recorded over an average period of 4 months. Conclusion : Clinicians need to be aware of the clinical features of BCG lymphadenitis. For management of BCG lymphadenitis, regular follow-up with observation should be the mainstay. Needle aspiration is a safe and easy treatment for suppurative BCG lymphadenitis.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.105-111
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• 1979

This experiment was carried out to define the affinity of alfalfa varieties to nodule bacteria and the effects of nodule bacteria on the growth of alfalfa varieties. The results obtained are summarized as follows; 1. The ability of nodule formation on the roots of alfalfa was significantly different among the strains of nodule bacteria, Rhizobium meliloti SU 47 formed nodules on the roots of two alfalfa varieties, Luna and Von arnims altd bost. Nodules were not formed at the roots of all varieties by inoculation of Rhizobium meliloti M1 but a lot of nodules were formed at the roots of all varieties by inoculation of Rhizobium meliloti M14. 2. When the Rhizobium meliloti M14 was inoculated in the media, the largest numbers of nodules were formed on the roots of alfalfa cultivar Franks hangmeiler and the least numbers of nodules were formed on the roots of cultivar Elga. 3. The plant height and the dry matter weight of all alfalfa cultivars were significantly increased by inoculation of Rhizobium meliloti M14, and also those were increased by applying nitrogen, but when the alfalfa cultivars were grown on the media inoculated Rhizobium M1, the plant height and the dry matter weight of alfalfas were not increased and they were same as those grown on check media. 4. The significant correlation were not detected between the number of nodules formed on the, roots of alfalfa cultivars and the plant height or the dry matter weight of alfalfa cultivars.