• Microbiology and Biotechnology Letters
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• v.36 no.1
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• pp.21-27
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• 2008

As an effort to search new bacterial biocontrol agents against pepper anthracnose, we screened myxobacteria, which might inhibit the growth of Colletotrichum acutatum, the agent of that plant disease. When 93 myxobacterial strains including 59 Myxococcus spp. and 34 Corallococcus spp. were tested against C. acutatum ACYSJ001 on agar plates, 10 strains identified as the genus Myxococcus significantly obstructed the growth of C. acutatum, whereas the majority of strains belonging to the genus Corallococcus did not demonstrate any counteractive effect. Such results have indicated that the strains of the genus Myxococcus have a high potential to play roles of biocontrol agents for control of pepper anthracnose. These also have revealed that the strains of the genus Myxococcus could be used as excellent microbial resources for screening novel antifungal substances.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.195-199
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• 2009

To select antifungal surfactants, control efficacy of various nonionic and anionic surfactants on cucumber powdery mildew was evaluated under greenhouse conditions. Among 14 surfactants, pentaetylene glycol monododecyl ether ($C_{12}E_5$), mixture of heptaethylene glycol monodecyl ether and heptaethylene monododecyl ether, and heptaethylene glycol mono-9-octadecenyl ether effectively reduced the development of powdery mildew on cucumber plants. Among the surfactants, $C_{12}E_5$ gave the best control efficacy on the disease and did not show phytotoxic response in cucumber plants. Whereas, fenarimol at a recommended rate (31.3 mg/L) showed less control activity than the surfactant (1,000 mg/L). In addition, mixtures of the surfactant and DBEDC, a protective fungicide, showed high control efficacies against powdery mildews of cucumber and strawberry by additive effect in greenhouse tests.

• Mycobiology
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• v.40 no.4
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• pp.244-251
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• 2012

In vitro and greenhouse screening of seven rhizobacterial isolates, AB05, AB10, AB11, AB12, AB14, AB15 and AB17, was conducted to investigate the plant growth promoting activities and inhibition against anthracnose caused by Colletotrichum acutatum in pepper. According to identification based on 16S rDNA sequencing, the majority of the isolates are members of Bacillus and a single isolate belongs to the genus Paenibacillus. All seven bacterial isolates were capable of inhibiting C. acutatum to various degrees. The results primarily showed that antibiotic substances produced by the selected bacteria were effective and resulted in strong antifungal activity against the fungi. However, isolate AB15 was the most effective bacterial strain, with the potential to suppress more than 50% mycelial growth of C. acutatum in vitro. Moreover, antibiotics from Paenibacillus polymyxa (AB15) and volatile compounds from Bacillus subtilis (AB14) exerted efficient antagonistic activity against the pathogens in a dual culture assay. In vivo suppression activity of selected bacteria was also analyzed in a greenhouse with the reference to their prominent in vitro antagonism efficacy. Induced systemic resistance in pepper against C. acutatum was also observed under greenhouse conditions. Where, isolate AB15 was found to be the most effective bacterial strain at suppressing pepper anthracnose under greenhouse conditions. Moreover, four isolates, AB10, AB12, AB15, and AB17, were identified as the most effective growth promoting bacteria under greenhouse conditions, with AB17 inducing the greatest enhancement of pepper growth.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10b
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• pp.48-49
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• 2003

This project was conducted to development several camellia tea mixed herb teas having any physiological effects. Leaves of tea tree contain many compounds, such as polysaccharides, volatile oils, vitamins, minerals, purines, alkaloids(eg. caffeine) and polyphenols(catechins and flavonoids). Although all three tea types(green, oolonr and black) have antibacterial and free radical capturing(antioxidizing) activities, the efficacy decreases substantially the darker the variety of tea is. This is due to lower contents of anti-oxidizing polyphenols remaining in the leaves. Unlike tea tree(Camellia sinensis), the biochemical features and effects of camellia(Camellia japonica) are not well known. Fresh mature leaf of sasanqua camellia(C. sasanqua), roasted young leaf tea(C. japonica) and fresh mature leaf and bark of camellia had high antibacterial activity against P. vulgaris and B. subtilis. In antifungal activity bioassay, young leaf roasted teas of camellia and sasanqua camellia had high activity against C. albicans and T. beigelil. Plant extracts from Camelia japonica had higher inhibitory activity against fungi than against bacteria. In cytotoxic effect against human acute myelogenous leukaemia cell extracts including fresh leaf(200$\mu\textrm{g}$/m1), bark(230$\mu\textrm{g}$/ml) and flower tea (320$\mu\textrm{g}$/m1)inhibited growth of AML cells.(중략)

• Advances in Traditional Medicine
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• v.8 no.4
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• pp.400-407
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• 2008

The aim of the present study is to investigate the anti-inflammatory and antimicrobial activity of petroleum ether and ethanol extracts of Scutia myrtina (Family: Rhamnaceae). In anti-inflammatory activity carrageenan and histamine induced paw oedema and cotton pellet induced granuloma for acute and chronic inflammatory models were studied in Wister albino rats. Based on the results of the present study it can be concluded that petroleum ether and ethanol extract of Scutia myrtina at 400 mg/kg has potential anti-inflammatory effect and they act in a dose dependent manner. Both extracts of Scutia myrtina showed antimicrobial activity against all bacterial and fungal strains tested at the concentration of $100\;{\mu}g$/ml. From the result, it can be concluded that the Scutia myrtina contain antibacterial and antifungal principle. Further more, besides the confirmation of the popular use; the obtained results demonstrate this herbal drug to represent a new source of antimicrobial and anti-inflammatory agent.

• KSBB Journal
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• v.10 no.2
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• pp.196-203
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• 1995

The effects of majors nutrients and environmental factors on polyoxins biosysnthesis were examined for the overprodution of antifungal agent polyoxins using Streptomyces sp. 809-11. The cell mass at the exponential growth phase was increased when soluble starch was used, while the polyoxins biosynthesis was increased with the formation of filamentous mycelium when glucose was used as a carbon source. It was, therefore, recommendable to use both soluble starch and glucose simultaneously as carbon sources for the cell growth and polyoxins production. The high concentration of ammonium sulfate (151.4 mM) resulied in the improvement of polyoxins production. The optimal concentration of $K_2HPO_4$for polyoxins production was found to be 0.5mM. By applying fed-batch culture, polyoxins production was improved to about 2-folds compared to the result from the batch culture.

• Journal of Oral Medicine and Pain
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• v.33 no.1
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• pp.27-33
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• 2008

Candidiasis, an opportunistic infectious condition caused by the genus Candida, is the most common oral fungal infection in humans. The diagnosis of oral candidiasis can often be made based on recognition of its clinical pattern, but at times there is difficulty in making a clinical diagnosis because of its various manifestations. Several antifungal medications have been developed for managing fungal infections. Despite the availability of several effective antimycotics for the treatment of oral candidiasis, failure of therapy is not uncommon due to the unique environment of the oral cavity, where the flushing effect of saliva and the cleaning action of the oral musculature tend to reduce the drug concentration to sub-therapeutic levels. In this case report, we present two patients diagnosed with chronic hyperplastic candidiasis and median rhomboid glossitis, which are known as rare forms of candidiasis. In both cases, there was a significant reduction of clinical signs and symptoms when fluconazole was prescribed after the failure of initial nystatin therapy.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.210-221
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• 1995

The purpose of this study was performed to investigate the mineralization and differentiation of osteobalsts for bone regeneration in vitro and the effect of rate of the composition in periodontal cells on mineralization. For this study, healthy gingival tissues were surgically obtained from the patients during 1st premolar extraction for the purposes of orthodontic treament. Gingival tissue was washed several time with Phosphate buffered saline contained high concentration of antibiotics and antifungal agent, and cultured in Dulbecco's Modified Eagle's Medium(DMEM, Gibco, U.S.A.). Every cell were cultured in state at $37^{\circ}C$, 100% of humidity, 5% of $CO_2$ incubator. Bone marrow stromal cells were isolated from 5-clay-old rat femur with using medium irrigation mathod by syringe. Cell suspension medium were centrifuged at 1500 rpm for 5 min and then cultured in the petri dish. Two kinds of cell were freezed and stocked in the liquid nitrogen tank until experiment. Cell were incubated into the 24 multi-well plate with $5{\times}10^4$cell/well of medium at $37^{\circ}C$, 100% of humidity 5% $CO_2$ incubator for 24 hours. After discarded of the supernatent of medium, O.5ml of medium were reapplied and incubated. And counted the number of cell using the hemocytometer and inverted light microscope. We have measured the number of mineralized nodule with using Alizarin red S. staining in microscope. Furthermore every cell were observed the morphological change between every rate of co-culture of the two kinds of cell. The results were as follows; The rate of proliferation of co-culture cell revealed high rate tendency compared the bone marrow stromal cell only and low growth rate to compared with gingival fibroblast only. The tendency of formation of the mineralized nodule were observed dose-depend pattern of bone marrow stromal cell. It is concluded that the gingival fibroblast may inhibit the formation of mineralized nodule in the culture of the bone marrow stromal cell.

• Research in Plant Disease
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• v.20 no.2
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• pp.101-106
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• 2014

Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is one of the most important diseases on citrus. Although Satsuma mandarin cultivating mostly in Korea is moderately resistance to canker, occurrence of the disease were more frequently reported since last decade. Like other diseases in citrus, citrus canker was mainly protected by chemical fungicide in the field. Due to the side effect of the chemicals, alternative method of disease control is recently required. In this study four rhizobacterial strains TRH423-3, MRL408-3, THJ609-3 and TRH415-2 are selected by testing its antifungal activity against Xcc. Pre-inoculation with the selected rhizobacterial strains caused disease suppression on the citrus leaves after inoculation with the citrus canker pathogen. Similarly, in the field test symptoms of citrus canker were less developed in the citrus trees applied several times with the selected rhizobacterial strains compared with those of untreated trees. Therefore, it is suggested that the selected rhizobacterial strains may be valuable as an alternative method in the environment-friendly citrus farm.

• Korean Journal of Agricultural Science
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• v.31 no.1
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• pp.45-52
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• 2004

Bakanae Disease is an abnormal plant growth caused by Gibberella fujikuroi. The infected plants several inches taller than normal plants in seedbed and field. To control bakanae disease, we made a seed disinfectant from garlic extract. And we isolated allicin($C_6H_{10}OS_2$) from garlic extract and the content was 0.62%. In order to develop efftive seed disinfectant from Garlic extract, we compared it with three seed disinfectants(benomyl, prochloraz, fludioxonil). Prochloraz, fludioxonil and Garlic wettable powder controlled Bakanae disease of rice very well, while benomyl did not suppress the disease enough. Water temperature was turned to be an important factor for controlling the disease by treating seed disinfectants. It was confirmed that the seed disinfectant from garlic extract can be used as non-toxic agricultural medicines.