• Korean Journal of Environmental Agriculture
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• v.20 no.5
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• pp.335-339
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• 2001

Two successive in vitro experiments were carried out to examine the effect of MPS bacterial inoculation on growth, and nitrogen and phosphorus accumulation of maize plants under greenhouse condition in the same soil. There were four treatments, uninoculated control and three phosphate solubilizing bacterial inoculations, viz., Pseudomonas striata, Burkholderia cepacia and Serratia marcescens. The inoculated plants showed the higher plant height, total dry mass, nitrogen and phosphorus accumulation when compared to uninoculated control plants in both experiments. In the combined data analysis from two experiments, the plants inoculated with P. striata and B. cepacia showed significantly higher plant height, total dry mass and P accumulation when compared to S. marcescens inoculated plant and uninoculated control plants. The P. striata and B. cepacia inoculation enhanced total dry matter accumulation by 14% and phosphorus accumulation by 25% over the uninoculated control plants. The nitrogen and phosphorus concentration of maize plants were also increased due to MPS bacterial inoculation, however, the effect was not significant.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.202-205
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• 2006

Ginseng is major medicinal plant in Korea. Because of its long cultivation period the yield losses of 5 years of ginseng is 50% due to various diseases. The objective of this study is to select potential biocontrol agents. As the result of research so far achieved to contribute to rational prevention of ginseag plant disease for the stable cultivation of ginseng, three bacterial strains, Streptomyces lauretii strain B8180, Bacillus subtilis strain 8856, and Burkholderia cepacia strain 7944 were isolated from oak leaf compost. The strains showed antagonistic activities against five ginseng pathogenic fungi (Cylindrocarpon destructans, Rhizoctonia solani, Phytophthora cactorum, Botrytis cinerea, Fusarium solani f. sp. panacis) and control effects on Phytophthora blight.

• The Korean Journal of Mycology
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• v.32 no.1
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• pp.31-38
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• 2004

An endophytic bacterial strain EB215 that was isolated from cucumber (Cucumis sativus) roots displayed a potent in vivo antifungal activity against Colletotrichum species. The strain was identified as Burkholderia cepacia based on its physiological and biochemical characteristics, and 16S rDNA gene sequence. Optimal medium and incubation period for the production of antifungal substances by B. cepacia EB215 were nutrient broth (NB) and 3 days, respectively. An antifungal substance was isolated from the NB cultures of B. cepacia EB215 strain by centrifugation, n-hexane partitioning, silica gel column chromatography, preparative TLC, and in vitro bioassay. Its chemical structure was determined to be pyrrolnitrin by mass and NMR spectral analyses. Pyrrolnitrin showed potent disease control efficacy of more than 90% against pepper anthracnose (Colletotrichum coccodes), cucumber anthracnose (Colletotrichum orbiculare), rice blast (Magnaporthe grisea) and rice sheath blight (Corticium sasaki) even at a low concentration of $11.1\;{\mu}g/ml$. In addition, it effectively controlled the development of tomato gray mold (Botrytis cinerea) and wheat leaf rust (Puccinia recondita) at concentrations over $33.3\;{\mu}g/ml$. However, it had no antifungal activity against Phytophthora infestans on tomato plants. Further studies on the development of microbial fungicide using B. cepacia EB215 are in progress.

• Journal of Life Science
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• v.9 no.1
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• pp.1-7
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• 1999

To isolate of antagonistic bacteria to Phytophthora capsici, which cause Phytophthora blight in red pepper, 237 isolates of Pseudomonas spp. and 260 isolates of Bacillus spp. were screened in selective media from rhizosphere soils of red pepper at Kyongsan, Kyongju, Yongchon and Euisung in Kyongbuk. Among total 497 isolates, 8 isolates of Pseudomonas spp and 4 isolates of Bacillus spp. inhibited the mycelial growth of Phytophthora capsici above 50$\%$ . These antagonistic bacteria showed more inhibitory effect on TSA (tryptic soy agar) than V-8 juice agar. Four isolates, P0704, P1201, B1101 and B1901, showing the most prominent antagonistic activity were selected and identified as P. cepacia (P0704, P1201), B. polymyxa (B1101) and B. subtilis (B1901), respectively. Cell free filtrates of these isolates were shown to inhibit zoosporangia germination and mycelial growth of p. capsici indicating that these isolates turned out to be bacteria producing antifungal substances. As a result of antagonistic test to Phytophthora blight in green house p. cepacia (P0704) showed the highest antagonistic effect with 46.7$\%$ and the rest of them were in the range of 13.4$\%$ to 26.7$\%$ .

• Journal of Microbiology
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• v.44 no.3
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• pp.263-268
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• 2006

Pleurotus ostreatus is a widely cultivated white-rot fungus. Owing to its considerable enzymatic versatility p. ostreatus has become the focus of increasing attention for its possible utility in biobleaching and bioremediation applications. Interactions between microorganisms can be an important factor in those processes. In this study, we describe the presence of a bacterial species associated with P. ostreatus strain G2. This bacterial species grew slowly (approximately 30 days) in the liquid and semi-solid media tested. When p. ostreatus was inoculated in solid media containing Tween 80 or Tween 20, bacterial microcolonies were detected proximal to the fungal colonies, and the relevant bacterium was identified via the analysis of a partial 16S rDNA sequence; it was determined to belong to the Burkholderia cepacia complex, but was not closely related to other fungus-isolated Burkholderiaceae. New specific primers were designed, and confirmed the presence of in vitro P. ostreatus cultures. This is the first time that a bacterial species belonging to the B. cepacia complex has been found associated with P. ostreatus.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.223-230
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• 2010

The Burkholderia cepacia complex isolates causing bacterial fruit rot of apricot were characterized by speciesspecific PCR tests, recA-HaeIII restriction fragment length polymorphism (RFLP) assays, rep-PCR genomic fingerprinting, recA gene sequencing, and multilocus sequence typing (MLST) analysis. Results indicated that the isolates Bca 0901 and Bca 0902 gave positive amplifications with primers specific for B. vietnamiensis while the two bacterial isolates showed different recA-RFLP and rep-PCR profiles from those of B. vietnamiensis strains. In addition, the two bacterial isolates had a higher proteolytic activity compared with that of the non-pathogenic B. vietnamiensis strains while no cblA and esmR marker genes were detected for the two bacterial isolates and B. vietnamiensis strains. The two bacterial isolates were identified as Burkholderia seminalis based on recA gene sequence analysis and MLST analysis. Overall, this is the first characterization of B. seminalis that cause bacterial fruit rot of apricot.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.67-76
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• 2013

A chitinolytic bacterial strain having strong antifungal activity was isolated and identified as Burkholderia cepacia MPC-7 based on 16S rRNA gene analysis. MPC-7 solubilized insoluble phosphorous in hydroxyapatite agar media. It produced gluconic acid and 2-keto-gluconic acid related to the decrease in pH of broth culture. The antagonist produced benzoic acid (BA) and phenylacetic acid (PA). The authentic compounds, BA and PA, showed a broad spectrum of antimicrobial activity against yeast, several bacterial and fungal pathogens in vitro. To demonstrate the biocontrol efficiency of MPC-7 on late blight disease caused by Phyto-phthora capsici, pepper plants in pot trials were treated with modified medium only (M), M plus zoospore inoculation (MP), MPC-7 cultured broth (B) and B plus zoospore inoculation (BP). With the sudden increase in root mortality, plants in MP wilted as early as five days after pathogen inoculation. However, plant in BP did not show any symptom of wilting until five days. Root mortality in BP was markedly reduced for as much as 50%. Plants in B had higher dry weight, P concentration in root, and larger leaf area compared to those in M and MP. These results suggested that B. cepacia MPC-7 should be considered as a candidate for the biological fertilizer as well as antimicrobial agent for pepper plants.

• Korean Journal of Agricultural Science
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• v.44 no.2
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• pp.196-210
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• 2017

The synergistic effect on phosphate solubilization of single- and co-inoculation of two phosphate solubilizing bacteria, Burkholderia cepacia (C1) and Alcaligenes aquatilis (H6), was assessed in liquid medium and maize plants. Co-inoculation of two strains was found to release the highest content of soluble phosphorus (309.66 ?g/mL) into the medium, followed by single inoculation of B. cepacia (305.49 ?g/mL) and A. aquatilis strain (282.38 ?g/mL). Based on a plant growth promotion bioassay, co-inoculated maize seedlings showed significant increases in shoot height (75%), shoot fresh weight (93.10%), shoot dry weight (84.99%), root maximum length (55.95%), root fresh weight (66.66%), root dry weight (275%), and maximum leaf length (81.53%), compared to the uninoculated control. In a field experiment, co-inoculated maize seedlings showed significant increases in cob length (136.92%), number of grain/cob (46.68%), and grain weight (67.46%) over control. In addition, single inoculation of maize seedlings also showed improved result over control. However, there was no significant difference between single inoculation of either bacterial strains and co-inoculation of these two bacterial strains in terms of phosphate solubilization index, phosphorous release, pH of the media, and plant growth parameters. Thus, single inoculation and co-inoculation of these bacteria could be used as biofertilizer for improving maize growth and yield.

• Journal of Microbiology
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• v.45 no.3
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• pp.275-279
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• 2007

The aims of this study were to detect Burkholderia cepacia complex (Bcc) strains in a cohort of Cystic Fibrosis patients (n=276) and to characterize Bcc isolates by molecular techniques. The results showed that 11.23% of patients were infected by Bcc. Burkholderia cenocepacia lineage III-A was the most prevalent species (64.3%) and, of these, 10% was cblA positive and 50% esmR positive. Less than half of the strains were sensitive to ceftazidime, meropenem, piperacillin-tazobactam, and trimethoprim-sulfamethoxazole. About half of the strains (41%) had homogeneous profiles, suggesting cross-transmission. The infection by B. cenocepacia was associated to a high rate of mortality (p=0.01).

• Biomedical Science Letters
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• v.3 no.1
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• pp.55-67
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• 1997

Considering many problems caused by the abuse of antibiotics recently, the appearance of antibiotic resistance bacteria is believed to help the cure of patients greatly. From Jan. 1st, 1996 to Dec. 31, 1996, 6135 strains were examined after being asked of and seperated from the clinical pathology departments of general hospitals, and the isolation frequency of identified bacteria and the susceptibility of antibiotics showed the following result. 1. The isolation frequency of strains was Escherichia coli, 1134 strains (18.4%), Pseudomonas aeruginosa, 856 strains (13.9%), coagulase negative Staphylococcus, 793 strains (12.89%), Staphylococcus aureus, 555 strains (9.02%), B. cepacia, 421 strains (6.84%), Enterobacter cloacae, 366 strains (5.95%), Enterobacter faecalis (4.86%), and Klebsiella pneumonia, 220 strains (3.85%). 2. The isolation rate of specimen was urine, 1, 969 strains, wound 1, 104 strains, sputum 701 strains, blood 643 strains, vaginal swab, 342 strains, and eye discharge, 192 strains, 40% of urine strains were E. coli 18％ of wound strains were B. cepacia, 43.7％ of sputum were P. aeruginosa, and in blood strains there were Enterobacter cloacae (25.8%), coagulase negative Staphylococcus (19.6%), and P. aeruginosa (8.7%). 3. The result of antibiotics susceptibility showed that, among gram negative bacilli, P. aeruginoas had resistance in almost all antibiotics except ceftazidme imipenem. But B. cepacia, the same glucose non-fermentation gram negative bacilli had more than 90％ of sensitivity in aztreonam, ceftazidime, ciproflxacin, piperacillin, trimethoprim/sulfa and had resistance in the others. Enterococcus faecalis showed more than 85% of sensitivity in penicillin-G, ampicillin, ciprofloxacin. 4. In the case of specimen antibiotics susceptibility, Enterobacter cloacae was lower in specimen isolated from blood than in those isolated from others and p. aeruginosa was low in specimen isolated from urine, which showed that there was difference in specimen antibiotics susceptibility. The result of this study shows that there happen many resisitances in antibiotics used frequently and some countermeasure is necessary because many bacteria began to show new resistance. Also it is desirable that the choice of antibiotics for infection diagnosis and its cure should be made after the inspection of antibiotics.