• Applied Biological Chemistry
• /
• v.49 no.4
• /
• pp.276-280
• /
• 2006

Traditionally fermented Cheonggukjangs were collected from Gyeonggi and Gangwon provinces and 22 strains were isolated and identified by using 165 rDNA sequences. Most of the identified strains were Bacillus subtilis and B. licheniformis, B. subtilis and B. licheniformis are dominant in the Gyeonggi area and B. licheniformis in the Gangwon area. In the growth pattern of the isolated strains, the duration of lag phase was generally 5 to 7 hours and stationary phase was reached after 23 to 40 hours of incubation. Total cell populations at the stationary phase were between $1{\times}10^6\;CFU/ml$ and $5{\times}10^7\;CFU/ml$. The fermenting ability of carbohydrates of isolates showed some differences among the regions. The isolated strains from Yong-In, Gyeonggi showed higher fermenting abilities with D-xylose, xylitol, D-tagatose and Methyl-$\alpha$-D-mannopyranoside. D-lactose, D-tagatose, D-xylose, Methyl-$\alpha$-D-mannopyranoside, amygdalin, arbutin, esculin and 2-keto-gluconate were well fermented with the An-Seong's strains; L-rhamnose, inositol, D-mannitol, D-sorbitol, celibiose and gluconate with the Kawang-Ju's stains; and D-lactose with the Odaesan's strains.

• The Plant Pathology Journal
• /
• v.33 no.6
• /
• pp.543-553
• /
• 2017

Sesame (Sesamum indicum) is an important oil seed crop of Asia. Yields can be negatively impacted by various factors, including disease, particularly those caused by fungi which create problems in both production and storage. Foliar diseases of sesame such as Alternaria leaf blight may cause significant yield losses, with reductions in plant health and seed quality. The work reported here determined the incidence of Alternaria species infecting sesame seeds grown in the Punjab, Pakistan. A total of 428 Alternaria isolates were obtained from 105 seed samples and grouped into 36 distinct taxonomic groups based on growth pattern and morphological characters. Isolation frequency and relative density of surface sterilized and non-surface sterilized seeds showed that three isolates (A13, A47 and A215) were the most common morphological groups present. These isolates were further identified using sequencing of the Internal Transcribed Spacer (ITS) region of ribosomal DNA (rDNA) and the Alternaria major allergen gene (Alt a 1). Whilst ITS of rDNA did not resolve the isolates into Alternaria species, the Alt a 1 sequences exhibited > 99% homology with Alternaria alternata (KP123850.1) in GenBank accessions. The pathogenicity and virulence of these isolates of Alternaria alternata was confirmed in inoculations of sesame plants resulting in typical symptoms of leaf blight disease. This work confirms the identity of a major source of sesame leaf blight in Pakistan which will aid in formulating effective disease management strategies.

• Microbiology and Biotechnology Letters
• /
• v.39 no.1
• /
• pp.37-42
• /
• 2011

I isolated the actinomycete strain KH223 from soil samples collected from the Kye Ryong mountain area. This strain is antagonistic to the multidrug-resistant Acinetobacter baumannii. KH223 was confirmed as belonging to the genus Streptomyces based on the scanning electronmicroscopy(SEM) observations of the diaminopimelicacid(DAP) type and morphological and physiological characteristics. Comparison of the 16S rDNA nucleotide sequences revealed that KH223 has a relationship with Streptomyces galbus. Production of antibiotics by KH223 was most favorable when cultured on a glucose, polypeptone, and yeast extract(PY) medium for 6 days at 27$^{\circ}C$. The supernatant was found to exhibit an antimicrobial effect on various kinds of bacteria and fungi. Particularly, butanol and ethylacetate extracts of KH223 and cyclo(trp-trp) exhibited significant activity against A. baumannii at concentration ranges of 0.8-12.5 ${\mu}g$/mL, 5.0-25 ${\mu}g$/mL and 12.5${\rightarrow}$100 ${\mu}g$/mL, respectively. Moreover, in contrast to cyclo(trp-trp) had shown to activity against Micrococcus luteus JCM 1464 at the concentration of 12.5 ${\mu}g$/mL, the butanol extract of KH223 showed significant activity against Bacillus subtilis IAM 1069 and Micrococcus luteus JCM 1464 at the concentration of 0.4 and 0.8 ${\mu}g$/mL, respectively. These results suggest that KH223 may have a great potential in the production of new antibiotics to combat multidrug-resistant pathogens and further studies may be warranted for the same.

• Microbiology and Biotechnology Letters
• /
• v.32 no.2
• /
• pp.172-178
• /
• 2004

This research is performed for a biological control of Chinese cabbage clubroot, we isolated an antagonistic bacterium AC-3 against Plasmodiophora sp., causal pathogens of cabbage clubroot. The isolated strain was identified as Streptomyces sp. by culture morphology, biochemical reactions, and homology research based on l6S rDNA sequences. Streptomyces sp. AC-3 produced chitinase (9.3 units/$m\ell$) in culture broth. So Plasmodiophora sp. mycelia changed abnonnal swelling, curling and branching mycelia by Streptomyces sp. AC-3 culture. In a field infected by Plasmodiophora sp., the treatment of a organic fertilizer added 2% Streptomyces sp. AC-3 microbial inoculant, it resulted in about 50% reducing the severity of cabbage clubroot significantly on cabbage plants compared with treated organic fertilizer plants. Additional disease such as sclerotinia rot, fusarium wilt and pythium rot were also significantly reduced by the treatment of the organic fertilizer added Streptomyces sp. AC-3 microbial inoculant.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.6
• /
• pp.1011-1015
• /
• 2008

A Gram-negative, strictly aerobic, motile bacterial strain, designated Gsoil $124^T$, was isolated from a soil sample taken from a ginseng field in Pocheon Province (South Korea). The isolate contained Q-10 as the predominant lipoquinone, plus $C_{18:1}\;{\omega}7c$ and summed feature 4 ($C_{16:1}\;{\omega}6c$ and/or iso-$C_{15:0}$ 2-OH) as the major fatty acids. The G+C content of the genomic DNA was 68.1 mol%, and the major polar lipids consisted of sphingoglycolipid, phosphatidylglycerol, phosphatidylcholine, and phosphatidylethanolamine. A comparative 16S rRNA gene sequence analysis showed that strain Gsoil $124^T$ was most closely related to Sphingopyxis chilensis (98.7%), Sphingopyxis alaskensis (98.2%), Sphingopyxis witflariensis (98.2%), Sphingopyxis taejonensis (98.0%), and Sphingopyxis macrogoltabida (97.6%). However, the DNA-DNA relatedness between strain Gsoil $124^T$ and its phylogenetically closest neighbors was less than 22%. Thus, on the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil $124^T$ should be classified as representing a novel species in the genus Sphingopyxis, for which the name Sphingopyxis panaciterrae sp. nov. is proposed. The type strain is Gsoil $124^T$ (=KCTC $12580^T$=LMG $24003^T$).

• Journal of Microbiology and Biotechnology
• /
• v.28 no.6
• /
• pp.883-892
• /
• 2018

Probiotics, including Enterococcus faecium, confer a health benefit on the host. An Enterococcus strain was isolated from healthy chicken cecum, identified as E. faecium by 16S rDNA gene sequence analysis, and designated as E. faecium L11. To evaluate the potential of E. faecium L11 as a probiotic, the gastrointestinal tolerance, immunomodulatory activity, and lifespan extension properties of the strain were assayed. E. faecium L11 showed >66% and >62% survival in artificial gastric juice (0.3% pepsin, pH 2.5) and simulated small intestinal juice (0.5% bile salt and 0.1% pancreatin), respectively. Heat-killed E. faecium L11 significantly (p < 0.05) increased immune cell proliferation compared with controls, and stimulated the production of cytokines (IL-6 and $TNF-{\alpha}$) by activated macrophages obtained from ICR mice. In addition, E. faecium L11 showed a protective effect against Salmonella Typhimurium infection in Caenorhabditis elegans. In addition, feeding E. faecium L11 significantly (p < 0.05) extended the lifespan of C. elegans compared with the control. Furthermore, genes related to aging and host defense were upregulated in E. faecium L11-fed worms. In conclusion, E. faecium L11, which prolongs the lifespan of C. elegans, may be a potent probiotic supplement for livestock.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.5
• /
• pp.924-931
• /
• 2004

A bacteriocin-producing lactic acid bacterium, which strongly inhibited the Lactobacillus plantarum recognized as an important acid spoilage microorganism in kimchi fermentation, was isolated from kimchi. From morphological, physiological, sugar fermentation, biochemical tests, and l6S rDNA sequencing results, the isolate was identified as an Enterococcus sp. and designated as Enterococcus sp. K25. The bacteriocin produced by Enterococcus sp. K25 inhibited several Gram-positive bacteria, including Lb. plantarum, whereas it did not inhibit Gram-negative bacteria and yeasts. Optimal temperature and pH for the bacteriocin production were $25^\circ{C}$ and 5.5, respectively. Enterococcus sp. K25 was applied to kimchi manufacturing alone and together with other preservatives (i.e., chitosan and fumaric acid). In addition, growth of lactic acid bacteria, pH, and titratable acidity (TA) were measured during aging at $5^\circ{C}$ and $10^\circ{C}$. Inoculation of Enterococcus sp. K25 together with fumaric acid showed the most synergistic effect on extension of kimchi shelf-life. Compared to control (no addition), the treatment prolonged the kimchi shelf-life up to 6 days, whereupon the eight-point TA value recognized as the edible limit was reached.

• KSBB Journal
• /
• v.26 no.6
• /
• pp.538-542
• /
• 2011

The research was purposed production of oligosaccharide from alginate hydrolysis the main composition in cell walls of sea weed. We was isolated 252 strains from sea water and mud flat, the highest alginate lyase activity was selected, and identified as Sanguibacter keddieii NC9 by 16S rDNA sequence analysis. In this study was select the sodium alginate concentration, pH, temperature for the production of alginate lyase activity. Alginate lyase activity was confirmed from plate assay with 10% cetylpyridinium chloride. The optimum culture conditions for the production of alginate lyase were sodium alginate 10 g/L, peptone 5 g/L, $40^{\circ}C$, pH 9 and 36 hours incubation time. Sanguibacter keddieii NC9, its alginate lyase would be useful for the production of bioenergy and biofunctional oligosaccharides from sea weed.

• Food Science and Preservation
• /
• v.20 no.5
• /
• pp.727-734
• /
• 2013

The antifungal activity against cheese fungi by lactic acid bacteria isolated from kimchi was investigated. Eight fungi were isolated from cheese in the cheese ripening room. Two of them were identified as Penicillium and Cladosporium via ITS-5.8S rDNA analysis. Twenty-two species of lactic acid bacteria with antifungal activity were isolated from kimchi. Two of them were identified as Lactobacillus and Pediococcus via 16S rRNA sequence analysis. Of the 22 lactic acid bacteria species, six were selected (L. sakei subsp. ALJ011, L. sakei subsp. ALI033, L. sakei subsp. ALGy039, P. pentosaceus ALJ015, P. pentosaceus ALJ024 and P. pentosaceus ALJ026) due to their higher activity against the eight fungi isolated from cheese in the cheese ripening room; and among the six species, the P. pentosaceus ALJ015 and P. pentosaceus ALJ024 isolates from the Jeonju area kimchi and the L. sakei subsp. ALI033 isolate from the Iimsil area kimchi had higher antifungal activity than the other lactic acid bacteria. The minimum inhibitory concentration (MIC) of L. sakei subsp. ALI033 against the eight fungi isolated from cheese in the cheese ripening room was $62.5{\mu}g/mL$.

• Food Engineering Progress
• /
• v.15 no.2
• /
• pp.182-187
• /
• 2011

A proteolytic lactic acid bacterium was isolated from Korean traditional fermented foods. The isolate BV-26, which had a protease activity (24 U/mg-crude protein), was identified as Lactobacillus plantarum by the API 50CHL kit and 16S rDNA analysis (99.9% of homology), and named as L. plantarum BV-26. Cell growth and protease activity of L. plantarum BV-26 was determined in MRS broth using 5L jar fermentor at $30^{\circ}C$. The maximum growth of L. plantarum BV-26 was reached at 18 hr in MRS broth, while protease activity of BV-26 was detectable at 12 hr and the highest activity was obtained after 16 hr cultivation. Therefore, we expect that the proteolytic lactic acid bacteria, L. plantarum BV-26, may be used as a starter for the fermentation of animal feed. Especially, the fermentation of soybean meal with the strain can be applied for improving feed utilization.