• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1744-1749
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• 2010

The role of endophytic fungi in plant growth and development is well documented. However, endophytic fungi with growth promotion capacity have never been isolated from weeds previously. In the current study, we isolated 8 fungal endophytes from the roots of Monochoria vaginalis, a serious weed of rice paddy in Korea. These isolates were screened on Waito-C, in order to identify plant growth promoting metabolites. Two fungal isolates (M5.A & M1.5) significantly promoted the plant height and shoot length of Waito-C during preliminary screening experiments. The culture filtrates (CFs) of M5.A and M1.5 also promoted the shoot length of Echinocloa crusgalli. Gibberellins (GAs) analysis of the CFs of M5.A and M1.5 showed that these endophytic fungi secrete higher quantities of GAs as compared with wild-type G. fujikuroi KCCM12329. The CF of M5.A contained bioactive GAs ($GA_3$, 2.8 ng/ml; $GA_4$, 2.6 ng/ml, and $GA_7$, 6.68 ng/ml) in conjunction with physiologically inactive $GA_9$ (1.61 ng/ml) and $GA_{24}$ (0.18 ng/ml). The CF of M1.5 contained physiologically active GAs ($GA_3$, 1.64 ng/ml; $GA_4$, 1.37 ng/ml and $GA_7$, 6.29 ng/ml) in conjunction with physiologically inactive $GA_9$ (3.44 ng/ml), $GA_{12}$ (0.3 ng/ml), and $GA_{24}$ (0.59 ng/ml). M5.A and M1.5 were identified as new strains of Penicillium sp. and Aspergillus sp., respectively, based on their 18S rDNA sequence homology and phylogenetic analysis.

• Journal of Microbiology and Biotechnology
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• v.19 no.1
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• pp.99-107
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• 2009

Strain PUPC1 produces an antifungal protease as well as plant growth promoting enzymes such as 1-aminocyclopropane-1-carboxylate (ACC) deaminase and phosphatase. Morphological, cultural, and physiological characteristics as well as 16S rRNA gene-sequence-based phylogenetic analysis confirmed the taxonomic affiliation of PUPC1 as Chryseobacterium aquaticum. The optimum growth of PUPC1 was observed at pH 6.0 and $30^{\circ}C$, and maximum protease production was observed in medium B amended with 1% tryptone, 0.5% sucrose, and 0.005% $MnCl_2$. The protease was purified by ammonium sulfate precipitation, Sephadex G-75 gel filtration chromatography, and electroelution from preparative SDS-PAGE. The protease had a molecular mass of 18.5 kDa. The optimum pH and temperature stability of the protease were pH 5.0-10.0 and temperature $40-70^{\circ}C$. Chryseobacterium aquaticum PUPC1 and its protease showed a broad-spectrum antifungal activity against phytopathogenic fungi. Strain PUPC1 also exhibited plant growth promoting traits. The objective of the present investigation was to isolate a strain for agricultural application for plant growth promotion and biocontrol of fungal diseases.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1115-1122
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• 2002

To evaluate the physiological properties of 22 varieties of legumes, antioxidative activity, antimutagenicity against Mitomycin C, genotoxicity, and mutagenicity were tested. Ethanolic extracts of legumes had significant antioxidative activities in the tests of electron-donating ability to DPPH radical, hydroxy radical-scavenging activity, and inhibitory effect on lipid auto-oxidation model system. Soy sprout bean (green), mung bean, and small black bean (green) had excitatory effects on the growth of E. coli PQ 37 cell. Black bean and green soy bean had inhibitory effects on the mutagenicities of the cells. Rice bean, pea, mung bean, and bonavista bean showed antimutagenic activities against chemical mutagen, Mitomycin C. Thus, rice bean and mung bean were found to be appropriate auxiliary ingredients of rice cake and rice processing food for the promotion of health and augmentation of rice and legume consumptions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.526-534
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• 1996

This study was conducted to find out the effects of crude extracts from welsh onion, onion, chinese chives and garlic on the seedling growth of chrysanthemum, lettuce, rice, radish, chinese cabbage, cucumber and oriental melon. The crude extracts from Allium spp. inhibited the growth of chrysanthemum and lettuceseedlings at low concentration, the effect increased as the concentration grew higher, and especially in lettuce, the radicle growth was inhibited greater than the hypocotyl growth.The root extracts from welsh onion, chinese chives, and stem-leaf extracts from welsh onion, chinese chives and garlic significantly promoted the root growth of rice seedlings at 300∼700ppm and at 500∼1,000ppm, respectively, and the leaf sheath was elongated at low concentration of all extracts. The stem-leaf extracts from garlic and onion promoted the root and hypocotyl growth of chinese cabbage up to 2,000ppm or 3,000ppm. Root extracts from all Allium spp. promoted the elongation of chinese cabbage root up to 300∼700ppm, but they didn't influence its hypocotyl elongation. At low concentration of onion, garlic and chinese chives extracts, the growth of radish seedlings was highly promoted. The promotive effect, however, declined as the concentration increased. Only, extracts of chinese chives promoted the growth of radish seedling up to 5,000ppm. The stem-leaf extracts from onion and garlic promoted hypocotyl growth in pepper, up to 5,000ppm, but had little effect on other treatments. All of the extracts markedly promoted both root(main and lateral root) and hypocotyl growth in cucumber seedlings. A higher degree of promotion was made in the cucumber lateral root by onion and garlic extracts. The seedling growth of oriental melon was slightly increased by low concentration, but high concentration inhibited the root and hypocotyl growth.

• The Korean Journal of Mycology
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• v.43 no.3
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• pp.200-205
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• 2015

Perilla frutescens var. japonica Hara was collected from farmland in Seongju-gun. Fifteen endophytic fungal strains with different colony morphologies were isolated from roots of P. frutescens. Waito-c rice seedlings were treated with the concentrated culture filtrates (CF) of endophytic fungi for observation of their plant growth-promoting activities. In the results, the CF of Y2H001 fungal strain promoted the growth of the waito-c rice seedlings. The phylogenetic tree of Y2H001 strain was analyzed by the combined sequences of the partial internal transcribed spacer region (ITS) and partial betatubulin gene. Molecular and morphological studies identified the Y2H001 strain as belonging to Aspergillus flavus. In gas chromatography mass spectrometry (GC/MS) analysis of the CF of Y2H001 strain, gibberellic acid (GA) was detected and quantified. Therefore, we describe Y2H001 strain as a new $GA_3$-producing A. flavus based on morphological, molecular characteristics and analysis of secondary metabolite.

• Microbiology and Biotechnology Letters
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• v.39 no.4
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• pp.324-329
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• 2011

Eight endophytic fungal strains were isolated from the roots of Calystegia soldanella from the western coast of South Korea. The culture filtrate of the eight endophytic fungi were applied to waito-c rice seedlings in order to verify potential plant growth promotion activities. The results of bioassay indicated that the Cs-9-7 fungal strain possessed the highest plant growth promotion activity. Fungal culture filtrates were analyzed to verify secondary metabolites using gas chromatography and mass spectroscopy with selected ion monitoring (GC/MS-SIM). The culture filtrate of the Cs-9-7 fungal strain was confirmed to contain gibberellins GA3 (1.229 ng/mL), GA4 (3.535 ng/mL), GA7 (1.408 ng/mL) and GA12 (0.378 ng/mL). Polymerase chain reactions (PCR) were performed so as to determine the internal transcribed spacer (ITS) regions for the identification of isolated strains with universal primers ITS-1 and ITS-4. The Cs-9-7 fungal strain, isolated from the root of C. soldanella, has been named Aspergillus tubingensis Cs-9-7.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1244-1249
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• 2009

Endophytic fungi are known for the production of valuable metabolites, but information on the gibberellin production capacity of this group is limited. We isolated 9 endophytic fungi from the roots of salt-stressed soybean plants and screened them on waito-c rice, in order to identify plant growth promoting fungal strains. The fungal isolate TK-2-4 gave maximum plant length (20.35 cm) promotion in comparison with wild-type Gibberella fujikuroi (19.5 cm). In a separate experiment, bioassay of TK-2-4 promoted plant length and biomass of soybean cultivar Taegwangkong. The TK-2-4 culture filtrate was analyzed for the presence of gibberellins, and it was found that all physiologically active gibberellins, especially $GA_4$ and $GA_7$, were present in higher amounts ($GA_1$, 0.11 ng/ml; $GA_3$, 2.91 ng/ml; $GA_4$, 3.21 ng/ml; and $GA_7$, 1.4 ng/ml) in conjunction with physiologically inactive $GA_9$ (0.05 ng/ml), $GA_{12}$ (0.23 ng/ ml), $GA_{15}$ (0.42 ng/ml), $GA_{19}$ (0.53 ng/ml), and $GA_{20}$ (0.06 ng/ml). The fungal isolate TK-2-4 was later identified as a new strain of Phoma herbarum, through the phylogenetic analysis of 28S rDNA sequence.

• Journal of Distribution Science
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• v.12 no.8
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• pp.83-90
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• 2014

Purpose - Increasing sales of PB rice products can hinder the growth of domestic brands of rice, notwithstanding that the government is promoting domestic brands of rice. This analysis evaluated the influencing relationship among the variables of PB image, product credibility, and purchase intention of consumers who have never bought PB rice, to know the factors influencing consumers' decisions to purchase PB products. Research design, data, and methodology - PB products' brand image was analyzed as the factor that has a direct effect on purchase intention. The mediation effect of credibility on PB products is also analyzed, in terms of influencing the relationship between PB products' brand image and purchase intention. The analysis is performed on consumers that have not purchased a PB product and consumers who have purchased PB products from major distributors. Data is collected through questionnaires, from 389 of responders, and the AMOS 19.0 statistics package is used as a statistical tool. Results - It is proven that brand image has direct effects on the credibility of the product, and the credibility of product has a direct effect on purchase intention. However, it is revealed that brand image does not directly affect purchase intention, but that brand image indirectly affects it through the credibility of the product. Although the customers' recognition about PB image is low, the result shows that PB products' external attributes have effects on customers' purchase intention relating to the PB product. Therefore, it is important to establish the credibility of the PB product more than other products in terms of marketing. Conclusions - The following are the implications of the study. First, in a rice brand promotion, the credibility of the product should be ensured by a uniform brand image. To ensure the credibility of a product, the RPC brand and other brands should be unified, and the unified brand image should be applied to every product. Second, the package must possess a design as well as contents that could build consumers' perception of product credibility. Products' external attributes contribute to their credibility, which leads the consumers to purchase the products, including those consumers who have never bought PB rice products. Therefore, the products' credibility and sales can be reinforced by applying information about consumers' considerations when buying the PB rice product in different colors, font sizes, and packaging designs. This study is meaningful in two ways. First, it seeks to identify an NB revitalization strategy by exploring the purchasing behavior of customers who have no experience in buying PB rice products. Second, the results of previous studies about general brands are considered and applied in this study in order to investigate the influencing relationship among different factors of PB products. However, this study is a consumer awareness investigation; therefore, its results only have limited meaning to the relationship between brand image and purchase intention.

• Journal of Life Science
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• v.18 no.10
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• pp.1355-1359
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• 2008

Endophytic fungi predominantly inhabit grasses, and produce a variety of beneficial metabolites for plant growth, as well as help their hosts against pathogens and herbivores. Current study was focused on plant growth promoting activity of endophytic fungi inhabited in the roots of sand dune grasses. We collected 49 fungal isolates from the roots of four most common sand dune grasses and screened them for their growth promoting capacity. Results showed that 37 fungal isolates (75.5%) promoted plant height and shoot length of waito-c rice, 11 fungal isolates (22.5%) suppressed it, while 1 fungus (2%) showed no effect on the growth attributes. The fungal strain Gibberella fujikuroi, along with distilled water and Czapek broth medium, were taken as control for this experiment. It was concluded that a major proportion of endophytic fungi inhabited in the sand dune plants produce metabolites, and thus help in growth and development of the host plant.

• KSBB Journal
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• v.24 no.4
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• pp.334-340
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• 2009

For the isolation of a plant growth-promoting rhizobacteria, strain YK-5 was selected from approximately 400 thermostable strains isolated from special soil samples. Strain YK-5 produced an antifungal compound, and optimum carbon and nitrogen sources for the production of the antifungal compound were investigated against Aspergillus flavus as a test strain. Modified LB medium containing 1% peptone, 1% yeast extract and 5% black sugar was determined to be the optimal medium for growth and antifungal compound production. Culture broth of strain YK-5 potently inhibited growth of the phytopathogenic fungus Fusarium oxysporum KACC 40052 for 7 days. The plant growth-promotion function of strain YK-5 was tested against radish and rice in pot trials. Leaf number, plant height and root length in YK-5-treated radish markedly exceeded (> 60%) those of untreated radish. Leaf length and white rootlet development were markedly more prominent than in commercially-treated rice plants. Strain YK-5 was determined to be Bacillus subtilis YK-5 by physiological, chemotaxonomical, and phylogenetical analyses.