• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.497-502
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• 2008

The essential oil from the cones of Pinus koraiensis was prepared after removing the seeds, and its chemical composition analyzed using gas chromatography-mass spectrometry (GC-MS). Hydrodistillation of the P. koraiensis cones yielded 1.07% (v/w) of essential oil, which was almost three times the amount of essential oil extracted from the needles of the same plant. Moreover, the antimicrobial activities of the oil against the growth of Gram-positive bacteria, Gram-negative bacteria, and fungi were evaluated using the agar disc diffusion method and broth microdilution method. Eighty-seven components, comprising about 96.8% of the total oil, were identified. The most abundant oil components were limonene (27.90%), ${\alpha}$-pinene (23.89%), ${\beta}$-pinene (12.02%), 3-carene(4.95%), ${\beta}$-myrcene (4.53%), isolongifolene (3.35%), (-)-bornyl acetate (2.02%), caryophyllene (1.71%), and camphene (1.54%). The essential oil was confirmed to have significant antimicrobial activities, especially against pathogenic fungal strains such as Candida glabrata YFCC 062 and Cryptococcus neoformans B 42419. Therefore, the present results indicate that the essential oil from the cones of Pinus koraiensis can be used in various ways as a nontoxic and environmentally friendly disinfectant.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.410-419
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• 2018

It is urgently required to construct safety data on agricultural by-products imported for use as medium materials for domestic mushroom production. However, research on microorganisms is insufficient. This study was conducted to investigate the presence of bacteria that have the possibility of harmful effects on human, plants and mushroom in wheat straw, peatmoss, cottonseed hull, cottonseed meal, and beet pulp imported from Australia, Canada, China, Egypt, Germany. Bacteria were found in the range of $1.35{\times}10^2$ to $8.34{\times}10^6CFU/g$. As a result of 16S rDNA sequence analysis, total of 19 genera and 45 species of bacteria were identified. Bacillus genus was dominant, followed by Paenibacillus genus. At the species level, diverse species was in the order of Firmicute, Proteobacteria and Actinobacteria. Regarding the agricultural by-products, straw and peat moss had more diverse bacteria than other agricultural by-products. Among the indentified bacteria, 6 species of 5 genera (Enterobacter asburiae, Enterobacter ludwigii, Stenotrophomonas maltophilia, Pseudomonas monteilii, Bacillus anthracis, and Cellulosimicrobium funkei) were present as potent harmful bacteria to human. Surprisingly, both the human and plant pathogenic Klebsiella pneumoniae subsp. pneumonia was present. Bacillus altitudinis was present as a plant pathogen. Lysinibacillus sphaericus, an insect pathogen, and Ochrobactrum pseudogrignonense, a mushroom pathogen, were also present. The results of this study confirmed that several kinds of pathogenic bacteria were present in the agricultural by-products for the mushroom cultivation medium imported into Korea. Our work suggests that hygiene inspection and management is urgently needed for imported agricultural by-products to be safely used for mushroom production.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.361-366
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• 1992

The antagonistic bacteria, showing distinguished effect against Fusarium oxysporum and Rhizoctonia solani were isolated from the rhizosphares of horticultural plants and identified as Bacillus subtilis. The strains were studied for their chracteristics of biochemistry, physiology, antagonistic effect against plant pathogenic fungi, and growth promoting effect on horticultural plants. The Bacillus thuringiensis(BT) HD-1 toxin gene was introduced into these B. subtilis. The BT toxin genes on chromosome of the bacteria were identified by southern blotting, but its proteins were not detected by SDS-PAGE. These transformed bacteria showed growth promoting effect and showed also insecticidal and antagonistic effects against Bombix mori and fungi F. oxysporum and R. solani but not against nematode Bursaphelenchus xylophilus.

• Journal of Life Science
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• v.17 no.11
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• pp.1547-1554
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• 2007

In this study was investigated the growth effect of Prunella vulgaris. aleutica Fernald(leaf and flower) extracts on various lactic acid bacterias, electron donating ability and hydroxyl radical scavenging activity. The total cell count of Enterococcus faecium KCCM 12118, Lactobacillus rhamnosus KCCM 32826, Lactobacillus plantarum KCCM 11542, Pediococcus pentosaceus KCCM 40464 in the absence at $37^{\circ}C$ after 48hr were $2.2{\times}10^9\;cfu/ml,\;2.1{\times}10^9\;cfu/ml,\;2.3{\times}10^9cfu/ml,\;2.2{\times}10^9\;cfu/ml$. On the other hand, the total cell count of E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCC 11542, P. pentosaceus KCCM 40464 in the presence of Prunella vulgaris. aleutica Fernald(leaf and flower) extracts(10%) at $37^{\circ}C$ after 48hr were $4.3{\times}10^9-4.5{\times}10^9\;cfu/ml,\;4.3{\times}10^9-4.5{\times}10^9\;cfu/ml,\;4.8{\times}10^9-4.9{\times}10^9\;cfu/ml,\;4.1{\times}10^9-4.1{\times}10^9\;cfu/ml$. The electron donating ability indicated to E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 added by 10% Prunella vulgaris. aleutica Fernald(leaf and flower) extracts, respectively. when 10% native plant extracts were added lactic acid bacterias, the electron donating ability is the highest. Hydroxyl radical scavenging activity of L. plantarum KCCM 11542, L. rhamnosus KCCM 32826, E. faecium KCCM 12118, P. pentosaceus KCCM 40464 showed higher than that of control.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1407-1429
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• 2007

The Burkholderia genus consists of over 40 Gram-negative, ${\beta}$-proteobacteria species that occupy remarkably diverse ecological niches. This genus contains species pathogenic to human, animals, and plants, as well as species involved in promoting plant growth and biodegradation of pollutants. This is largely explained by the extraordinary versatility of Burkholderia, as reflected by the remarkable diversity of extracellular products released by these bacteria. We exhaustively surveyed the extracellular enzymes, siderophores, toxins, antimicrobials, and other secondary metabolites produced by the members of this very diverse genus. Available information on regulation, especially quorum sensing mechanisms, and secretion is highlighted.

• Applied Chemistry for Engineering
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• v.23 no.5
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• pp.429-432
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• 2012

According to the requirement of novel antimicrobial agents for the rapidly increasing emergence of multi-drug resistant pathogenic microbes, a number of researchers have found new antibiotics to overcome this resistance. Among them, antimicrobial peptides (AMPs) are host defense molecules found in a wide variety of invertebrate, plant, and animal species, and are promising to new antimicrobial candidates in pharmatherapeutic fields. Therefore, this review introduces the antimicrobial action of antimicrobial peptide and ongoing development as a pharmetherapeutic agent.

• YAKHAK HOEJI
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• v.54 no.2
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• pp.122-125
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• 2010

The essential oil fraction was extracted from the aerial parts of the plant by steam distillation method and its composition was analyzed by GC-MS (gas chromatography-mass spectrometry) which led to the identification of 43 compounds. Dehydroelsholtzia ketone (56.81%) and elsholtzia ketone (30.05%) were identified as the predominant components of this oil. The antibacterial activities of the essential oil fraction were assessed by micro-dilution tests against antibioticsusceptible and -resistant strains of Streptococcus pneumoniae, Staphylococcus aureus, Salmonella enteritidis, and S. typhimurium. The oil inhibited most of the tested strains significantly resulting MICs (minimum inhibiting concentrations) between 2 mg/ml and >16 mg/ml. In most cases of this study Streptococcus pneumoniae and Staphylococcus aureus showed higher sensitivity to this oil than Salmonella strains.

• KSBB Journal
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• v.27 no.1
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• pp.9-15
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• 2012

Antimicrobial peptides are widely used in various organisms as a defense system against infection. The peptides are lethal towards bacteria and fungi, however have minimal toxicity in mammalian and plant cells. In this aspect, it is considered that antimicrobial peptides are new alternative materials for defensing against microbial infection. Here, we describe overall characteristics of antimicrobial peptides based on the mechanism of action, classification of the peptides, report detection/screening methods and chemical/biological production. It is expected that understanding of innate immune system based on antimicrobial peptides tends to develop novel natural antimicrobial agents, which might be applied for defensing pathogenic microorganisms resistant to conventional antibiotics.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1073-1079
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• 2005

To investigate plant protection, pathogenesis-related (PR) proteins and plant defense enzymes related to cell wall lignification were studied in pepper plants inoculated with antagonistic Bacillus subtilis HJ927 and pathogenic strain Phytophthora capsici. Phytophthora blight disease was reduced by $53\%$ in pepper roots when preinoculated with B. subtilis HJ927 against P. capsici. The activities of PR proteins (chitinase and ${\beta}$-1,3,-glucanase) and defense-related enzymes (peroxidase, polyphenoloxidase, and phenylalanine ammonia lyase) decreased in roots of B. subtilis+P capsid-treated plants, but increased in leaves with time. The decrease and increase were much greater in P. capsici-treated plants than in B. subtilis HJ927+P capsici-treated plants, although P. capsici-treated plants had more severe damage. Therefore, changes of enzyme activities do not seem to be directly related to plant protection. We suggest that the change of these enzymes in pathogen-treated plants may be related to plant response rather than to resistance against pathogen attacks.

• The Plant Pathology Journal
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• v.39 no.5
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• pp.430-448
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• 2023

Recently, strategies for controlling Fusarium oxysporum f. sp. lycopersici (Fol), the causal agent of Fusarium wilt of tomato, focus on using effective biocontrol agents. In this study, an analysis of the biocontrol and plant growth promoting (PGP) attributes of 11 isolates of loamy soil Bacillus spp. has been conducted. Among them, the isolates B.PNR1 and B.PNR2 inhibited the mycelial growth of Fol by inducing abnormal fungal cell wall structures and cell wall collapse. Moreover, broad-spectrum activity against four other plant pathogenic fungi, F. oxysporum f. sp. cubense race 1 (Foc), Sclerotium rolfsii, Colletotrichum musae, and C. gloeosporioides were noted for these isolates. These two Bacillus isolates produced indole acetic acid, phosphate solubilization enzymes, and amylolytic and cellulolytic enzymes. In the pot experiment, the culture filtrate from B.PNR1 showed greater inhibition of the fungal pathogens and significantly promoted the growth of tomato plants more than those of the other treatments. Isolate B.PNR1, the best biocontrol and PGP, was identified as Bacillus stercoris by its 16S rRNA gene sequence and whole genome sequencing analysis (WGS). The WGS, through genome mining, confirmed that the B.PNR1 genome contained genes/gene cluster of a nonribosomal peptide synthetase/polyketide synthase, such as fengycin, surfactin, bacillaene, subtilosin A, bacilysin, and bacillibactin, which are involved in antagonistic and PGP activities. Therefore, our finding demonstrates the effectiveness of B. stercoris strain B.PNR1 as an antagonist and for plant growth promotion, highlighting the use of this microorganism as a biocontrol agent against the Fusarium wilt pathogen and PGP abilities in tomatoes.